Rhythm-based heartbeat duration normalization for atrial fibrillation detection.

PubMed

Islam, Md Saiful; Ammour, Nassim; Alajlan, Naif; Aboalsamh, Hatim

2016-05-01

Screening of atrial fibrillation (AF) for high-risk patients including all patients aged 65 years and older is important for prevention of risk of stroke. Different technologies such as modified blood pressure monitor, single lead ECG-based finger-probe, and smart phone using plethysmogram signal have been emerging for this purpose. All these technologies use irregularity of heartbeat duration as a feature for AF detection. We have investigated a normalization method of heartbeat duration for improved AF detection. AF is an arrhythmia in which heartbeat duration generally becomes irregularly irregular. From a window of heartbeat duration, we estimate the possible rhythm of the majority of heartbeats and normalize duration of all heartbeats in the window based on the rhythm so that we can measure the irregularity of heartbeats for both AF and non-AF rhythms in the same scale. Irregularity is measured by the entropy of distribution of the normalized duration. Then we classify a window of heartbeats as AF or non-AF by thresholding the measured irregularity. The effect of this normalization is evaluated by comparing AF detection performances using duration with the normalization, without normalization, and with other existing normalizations. Sensitivity and specificity of AF detection using normalized heartbeat duration were tested on two landmark databases available online and compared with results of other methods (with/without normalization) by receiver operating characteristic (ROC) curves. ROC analysis showed that the normalization was able to improve the performance of AF detection and it was consistent for a wide range of sensitivity and specificity for use of different thresholds. Detection accuracy was also computed for equal rates of sensitivity and specificity for different methods. Using normalized heartbeat duration, we obtained 96.38% accuracy which is more than 4% improvement compared to AF detection without normalization. The proposed normalization method was found useful for improving performance and robustness of AF detection. Incorporation of this method in a screening device could be crucial to reduce the risk of AF-related stroke. In general, the incorporation of the rhythm-based normalization in an AF detection method seems important for developing a robust AF screening device. Copyright © 2016 Elsevier Ltd. All rights reserved.

Stroke of Known Cause and Underlying Atrial Fibrillation (STROKE-AF) randomized trial: Design and rationale.

PubMed

Bernstein, Richard A; Kamel, Hooman; Granger, Christopher B; Kowal, Robert C; Ziegler, Paul D; Schwamm, Lee H

2017-08-01

Approximately 20% of ischemic strokes are associated with clinically apparent atrial fibrillation (AF). Regardless of stroke etiology, detection of AF in patients with ischemic strokes often changes antithrombotic treatment from anti-platelet to oral anticoagulation therapy. The role and the optimum duration of cardiac monitoring to detect AF in patients with strokes presumed due to large vessel atherosclerosis or small vessel disease is unknown. This manuscript describes the design and rationale of the STROKE-AF trial. STROKE-AF is a randomized, controlled, open-label, post-market clinical trial. Detection of AF will be evaluated using continuous arrhythmia monitoring with an insertable cardiac monitor (ICM) compared with standard of care follow-up in patients with stroke (within the prior 10 days) that is presumed due to large vessel cervical or intracranial atherosclerosis, or to small vessel disease. Approximately 500 patients will be enrolled at approximately 40 centers in the United States. Patients will be randomized 1:1 to arrhythmia monitoring with an ICM (continuous monitoring arm) or standard of care follow-up (control arm). Subjects will be followed for ≥12 months and up to 3 years. The primary objective is to compare the incidence rate of detected AF through 12 months of follow-up between the two arms. This trial will provide information on the value of ICMs to detect subclinical AF in patients with stroke presumed due to large vessel atherosclerosis or small vessel disease, which will have implications for guiding treatment with oral anticoagulation for secondary stroke prevention. Copyright © 2017 Elsevier Inc. All rights reserved.

Diagnostic work-up for detection of paroxysmal atrial fibrillation after acute ischemic stroke: cross-sectional survey on German stroke units.

PubMed

Rizos, Timolaos; Quilitzsch, Anika; Busse, Otto; Haeusler, Karl Georg; Endres, Matthias; Heuschmann, Peter; Veltkamp, Roland

2015-06-01

Multiple methods to detect paroxysmal atrial fibrillation (pAF) in patients with acute stroke are available. However, it is unknown which approaches are currently used in clinical routine and guidelines remain vague to the extent of cardiac monitoring. We characterize diagnostic efforts for pAF detection on German stroke units (SU). A standardized anonymous questionnaire was sent to all clinical leads of certified SUs in Germany. The questionnaire focused on basic characteristics of SUs, procedures to detect AF, and estimates on AF detection. One hundred seventy-nine SU leads participated (response rate 71.6%). All patients undergo continuous bedside ECG monitoring. A percentage of 77.6 SUs initiate additional 24-hour Holter ECG in >50% of patients without known AF. Patients with transient ischemic attack are monitored significantly shorter than patients with ischemic stroke. Independent of SU type or size, 67.6% of leads assumed to fail detecting pAF in 5% to 20% of patients. In cryptogenic stroke, additional ECG monitoring is recommended by 90.2% but only 13.8% of SUs perform routine ECG follow-up visits. The use of implanted event recorders is low (1-10 patients/y by 60.7% of SUs; 28.1%: no use). A percentage of 83.9 do not use external event recorders. Our survey demonstrates substantial heterogeneity among German SUs on diagnostic work-up for pAF. Future prospective multicenter studies should systematically evaluate the impact of different methods to uncover pAF. © 2015 American Heart Association, Inc.

Prospective study of atrial fibrillation termination during ablation guided by automated detection of fractionated electrograms.

PubMed

Porter, Michael; Spear, William; Akar, Joseph G; Helms, Ray; Brysiewicz, Neil; Santucci, Peter; Wilber, David J

2008-06-01

Complex fractionated atrial electrograms (CFAE) may identify critical sites for perpetuation of atrial fibrillation (AF) and provide useful targets for ablation. Current assessment of CFAE is subjective; automated detection algorithms may improve reproducibility, but their utility in guiding ablation has not been tested. In 67 patients presenting for initial AF ablation (42 paroxysmal, 25 persistent), LA and CS mapping were performed during induced or spontaneous AF. CFAE were identified by an online automated computer algorithm and displayed on electroanatomical maps. A mean of 28 +/- 18 sites/patient were identified (20 +/- 13% of mapped sites), and were more frequent during persistent AF. CFAE occurred most commonly within the CS, on the atrial septum, and around the pulmonary veins. Ablation initially targeting CFAE terminated AF in 88% of paroxysmal AF, but only 20% of persistent AF (P < 0.001). Subsequently, additional ablation was performed in all patients (PV isolation for paroxysmal AF, PV isolation + mitral and roof lines for persistent AF). Minimum follow-up was 1 year. One-year freedom from recurrent atrial arrhythmias without antiarrhythmic drug therapy after a single procedure was 90% for paroxysmal AF, and 68% for persistent AF. Ablation guided by automated detection of CFAE proved feasible, and was associated with a high AF termination rate in paroxysmal, but not persistent AF. As an adjunct to conventional techniques, it was associated with excellent long-term single procedure outcomes in both groups. Criteria for identifying optimal CFAE sites for ablation, and selection of patients most likely to benefit, require additional study.

Current and Emerging Uses of Insertable Cardiac Monitors: Evaluation of Syncope and Monitoring for Atrial Fibrillation.

PubMed

Tomson, Todd T; Passman, Rod

Insertable cardiac monitors (ICMs) have provided clinicians with a superb tool for assessing infrequent or potentially asymptomatic arrhythmias. ICMs have shown their usefulness in the evaluation of unexplained syncope, providing high diagnostic yields in a cost-effective manner. While unexplained syncope continues to be the most common reason for their use, ICMs are increasingly being used for the monitoring of atrial fibrillation (AF). Recent trials have demonstrated that a substantial proportion of patients with cryptogenic stroke have AF detected only by the prolonged monitoring provided by ICMs. A particularly promising and emerging use for ICMs is in the management of anticoagulation in patients with known paroxysmal AF. The introduction in recent years of ICMs with automatic AF detection algorithms and continuous remote monitoring in combination with novel oral anticoagulants have opened the door for targeted anticoagulation guided by remote monitoring, a strategy that has recently shown promise in pilot studies of this technique. While further research is needed before official recommendations can be given, this use of ICMs opens exciting new possibilities for personalized medicine that could potentially reduce bleeding risk and improve quality of life in patients with atrial fibrillation.

Disease management: atrial fibrillation and home monitoring.

PubMed

Ricci, Renato Pietro

2013-06-01

Device-detected atrial fibrillation (AF) episodes predict poor clinical outcome regardless of symptoms. Potential benefits of remote monitoring are early arrhythmia detection and patient continuous monitoring. Several studies of device remote monitoring consistently demonstrated that AF represents the most common clinical alert and that detailed information on arrhythmia onset, duration, and burden as well as on the ventricular rate may be early available for clinical evaluation. Reaction time to AF alerts was very short in all series involving either pacemakers or defibrillators and action ability of AF alerts was very high. In the Home Guide Registry, in which 1650 patients were enrolled, AF was detected in 16.3% of patients and represented 36% of all cardiovascular events during the follow-up. Timely anticoagulation introduction in asymptomatic patients may impact on the stroke rate. According to the results of repeated Monte Carlo simulations based on a real population of 166 patients, daily monitoring may reduce the 2-year stroke risk by 9-18% with an absolute reduction of 0.2-0.6%, compared with conventional inter-visit intervals of 6-12 months. In the COMPAS trial, the incidence of hospitalizations for atrial arrhythmias and related stroke was significantly higher in the control group than in the remote monitoring group. Major questions will be addressed by the ongoing IMPACT trial in which a remote monitoring guided anticoagulation strategy based on AF detection will be compared with a physician-directed standard strategy. In patients with heart failure, AF early detection combined with other indexes may help prevent hospitalizations.

Yield of atrial fibrillation detection with Textile Wearable Holter from the acute phase of stroke: Pilot study of Crypto-AF registry.

PubMed

Pagola, Jorge; Juega, Jesus; Francisco-Pascual, Jaume; Moya, Angel; Sanchis, Mireia; Bustamante, Alejandro; Penalba, Anna; Usero, Maria; Cortijo, Elisa; Arenillas, Juan F; Calleja, Ana I; Sandin-Fuentes, Maria; Rubio, Jeronimo; Mancha, Fernando; Escudero-Martinez, Irene; Moniche, Francisco; de Torres, Reyes; Pérez-Sánchez, Soledad; González-Matos, Carlos E; Vega, Ángela; Pedrote, Alonso A; Arana-Rueda, Eduardo; Montaner, Joan; Molina, Carlos A

2018-01-15

We describe the feasibility of monitoring with a Textile Wearable Holter (TWH) in patients included in Crypto AF registry. We monitored cryptogenic stroke patients from stroke onset (<3days) continuously during 28days. We employed a TWH composed by a garment and a recorder. We compared two garments (Lead and Vest) to assess rate of undiagnosed Atrial Fibrillation (AF) detection, monitoring compliance, comfortability (1 to 5 points), skin lesions, and time analyzed. We describe the timing of AF detection in three periods (0-3, 4-15 and 16-28days). The rate of undiagnosed AF detection with TWH was 21.9% (32 out of 146 patients who completed the monitoring). Global time compliance was 90% of the time expected (583/644h). The level of comfortability was 4 points (IQR 3-5). We detected reversible skin lesions in 5.47% (8/146). The comfortability was similar but time compliance (in hours) was longer in Vest group 591 (IQR [521-639]) vs. Lead 566 (IQR [397-620]) (p=0.025). Also, time analyzed was more prolonged in Vest group 497 (IQR [419-557]) vs. Lead (336h (IQR [140-520]) (p=0.001)). The incidence of AF increases from 5.6% (at 3days) to 17.5% (at 15th day) and up to 20.9% (at 28th day). The percentage of AF episodes detected only in each period was 12.5% (0-3days); 21.7% (4-15days) and 19% (16-28days). 28days Holter monitoring from the acute phase of the stroke was feasible with TWH. Following our protocol, only five patients were needed to screen to detected one case of AF. Copyright © 2017 Elsevier B.V. All rights reserved.

Screening for Atrial Fibrillation in Patients ≥65 Years Using an Automatic Blood Pressure Monitor in a Skilled Nursing Facility.

PubMed

Wiesel, Joseph; Salomone, Thomas J

2017-10-15

Early detection of asymptomatic atrial fibrillation (AF) provides an opportunity to treat patients to reduce their risk of stroke. Long-term residents of skilled nursing facilities frequently have multiple risk factors for strokes due to AF and may benefit from screening for AF. Patients in a skilled nursing facility 65 years and older, without a history of AF and without a pacemaker or defibrillator, were evaluated using a Microlife WatchBP Home A automatic blood pressure monitor that can detect AF when set to a triple reading mode. Those with readings positive for AF were evaluated with a standard 12-lead electrocardiogram (ECG) or a 30-second single-channel ECG to confirm the presence of AF. A total of 101 patients were screened with an average age of 78 years, and 48 (48%) were female. Nine automatic blood pressure monitor readings were positive for possible AF. Of those, 7 (6.9%, 95% confidence intervals 3.0% to 14.2%) had AF confirmed with ECG. Only 2 (2%, 95% confidence interval 0.3% to 7.7%) were false-positive readings. One-time screening for AF using an automatic blood pressure monitor in a skilled nursing facility resulted in a high number of patients with newly diagnosed AF. Copyright © 2017 Elsevier Inc. All rights reserved.

A Simple Score That Predicts Paroxysmal Atrial Fibrillation on Outpatient Cardiac Monitoring after Embolic Stroke of Unknown Source.

PubMed

Ricci, Brittany; Chang, Andrew D; Hemendinger, Morgan; Dakay, Katarina; Cutting, Shawna; Burton, Tina; Mac Grory, Brian; Narwal, Priya; Song, Christopher; Chu, Antony; Mehanna, Emile; McTaggart, Ryan; Jayaraman, Mahesh; Furie, Karen; Yaghi, Shadi

2018-06-01

Occult paroxysmal atrial fibrillation (AF) is detected in 16%-30% of patients with embolic stroke of unknown source (ESUS). The identification of AF predictors on outpatient cardiac monitoring can help guide clinicians decide on a duration or method of cardiac monitoring after ESUS. We included all patients with ESUS who underwent an inpatient diagnostic evaluation and outpatient cardiac monitoring between January 1, 2013, and December 31, 2016. Patients were divided into 2 groups based on detection of AF or atrial flutter during monitoring. We compared demographic data, clinical risk factors, and cardiac biomarkers between the 2 groups. Multivariable logistic regression was used to determine predictors of AF. We identified 296 consecutive patients during the study period; 38 (12.8%) patients had AF detected on outpatient cardiac monitoring. In a multivariable regression analysis, advanced age (ages 65-74: odds ratio [OR] 2.36, 95% confidence interval [CI] .85-6.52; ages 75 or older: OR 4.08, 95% CI 1.58-10.52) and moderate-to-severe left atrial enlargement (OR 4.66, 95% CI 1.79-12.12) were predictors of AF on outpatient monitoring. We developed the Brown ESUS-AF score: age (65-74 years: 1 point, 75 years or older: 2 points) and left atrial enlargement (moderate or severe: 2 points) with good prediction of AF (area under the curve .725) and was internally validated using bootstrapping. The percentage of patients with AF detected in each score category were as follows: 0: 4.2%; 1: 14.8%; 2: 20.8%; 3: 22.2%; 4: 55.6%. The Brown ESUS-AF score predicts AF on prolonged outpatient monitoring after ESUS. More studies are needed to externally validate our findings. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

A Novel Application for the Detection of an Irregular Pulse using an iPhone 4S in Patients with Atrial Fibrillation

PubMed Central

McManus, David D.; Lee, Jinseok; Maitas, Oscar; Esa, Nada; Pidikiti, Rahul; Carlucci, Alex; Harrington, Josephine; Mick, Eric; Chon, Ki H.

2012-01-01

Background Atrial fibrillation (AF) is common and associated with adverse health outcomes. Timely detection of AF can be challenging using traditional diagnostic tools. Smartphone use is increasing and may provide an inexpensive and user-friendly means to diagnose AF. Objective To test the hypothesis that a smartphone-based application could detect an irregular pulse from AF. Methods 76 adults with persistent AF were consented for participation in our study. We obtained pulsatile time series recordings before and after cardioversion using an iPhone 4S camera. A novel smartphone application conducted real-time pulse analysis using 2 statistical methods [Root Mean Square of Successive RR Differences (RMSSD/mean); Shannon Entropy (ShE)]. We examined the sensitivity, specificity, and predictive accuracy of both algorithms using the 12-lead electrocardiogram as the gold standard. Results RMSDD/mean and ShE were higher in participants in AF compared with sinus rhythm. The 2 methods were inversely related to AF in regression models adjusting for key factors including heart rate and blood pressure (β coefficients per SD-increment in RMSDD/mean and ShE were −0.20 and −0.35; p<0.001). An algorithm combining the 2 statistical methods demonstrated excellent sensitivity (0.962), specificity (0.975), and accuracy (0.968) for beat-to-beat discrimination of an irregular pulse during AF from sinus rhythm. Conclusions In a prospectively recruited cohort of 76 participants undergoing cardioversion for AF, we found that a novel algorithm analyzing signals recorded using an iPhone 4S accurately distinguished pulse recordings during AF from sinus rhythm. Data are needed to explore the performance and acceptability of smartphone-based applications for AF detection. PMID:23220686

A novel application for the detection of an irregular pulse using an iPhone 4S in patients with atrial fibrillation.

PubMed

McManus, David D; Lee, Jinseok; Maitas, Oscar; Esa, Nada; Pidikiti, Rahul; Carlucci, Alex; Harrington, Josephine; Mick, Eric; Chon, Ki H

2013-03-01

Atrial fibrillation (AF) is common and associated with adverse health outcomes. Timely detection of AF can be challenging using traditional diagnostic tools. Smartphone use is increasing and may provide an inexpensive and user-friendly means to diagnoseAF. To test the hypothesis that a smartphone-based application could detect an irregular pulse fromAF. Seventy-six adults with persistent AF were consented for participation in our study. We obtained pulsatile time series recordings before and after cardioversion using an iPhone 4S camera. A novel smartphone application conducted real-time pulse analysis using 2 statistical methods: root mean square of successive RR difference (RMSSD/mean) and Shannon entropy (ShE). We examined the sensitivity, specificity, and predictive accuracy of both algorithms using the 12-lead electrocardiogram as the gold standard. RMSDD/mean and ShE were higher in participants in AF than in those with sinus rhythm. The 2 methods were inversely related to AF in regression models adjusting for key factors including heart rate and blood pressure (beta coefficients per SD increment in RMSDD/mean and ShE were-0.20 and-0.35; P<.001). An algorithm combining the 2 statistical methods demonstrated excellent sensitivity (0.962), specificity (0.975), and accuracy (0.968) for beat-to-beat discrimination of an irregular pulse during AF from sinus rhythm. In a prospectively recruited cohort of 76 participants undergoing cardioversion for AF, we found that a novel algorithm analyzing signals recorded using an iPhone 4S accurately distinguished pulse recordings during AF from sinus rhythm. Data are needed to explore the performance and acceptability of smartphone-based applications for AF detection. Copyright © 2013 Heart Rhythm Society. All rights reserved.

Improving atrial fibrillation detection in patients with implantable cardiac devices by means of a remote monitoring and management application.

PubMed

Zoppo, Franco; Facchin, Domenico; Molon, Giulio; Zanotto, Gabriele; Catanzariti, Domenico; Rossillo, Antonio; Baccillieri, Maria Stella; Menard, Cecile; Comisso, Jennifer; Gentili, Alessandra; Grammatico, Andrea; Bertaglia, Emanuele; Proclemer, Alessandro

2014-12-01

Atrial fibrillation (AF) is common in patients with cardiac implantable electronic devices (CIED) and has been associated with an increased stroke risk. The aim of our project was to assess the clinical value of a web-based application, Discovery Link AFinder, in improving AF detection in CIED patients. Seven Italian hospitals performed an observational study consisting of four phases. During phase 1, expert nurses and cardiologists prospectively followed-up CIED patients via in-hospital examinations and remote monitoring, and classified clinically relevant events, particularly AF occurrence. During phase 2, Discovery Link AFinder was exploited to identify patients who had suffered AF in the previous 12 months through the systematic scanning of device data remote transmissions. Phases 3 and 4 were repetitions of phases 1 and 2, respectively, and were implemented 6 months after the previous phases. A total of 472 consecutive patients were included in phase 1; AF occurred in 170 patients, 61 of whom were identified as new AF patients. Evidence of AF during this phase prompted prescription of oral anticoagulation (OAC) therapy in 30 patients. In phase 2, AFinder uncovered new AF, unidentified in phase 1, in 54 patients and prompted implementation of OAC therapy in 11 patients. During phase 3, 30 new AF patients were identified by means of remote monitoring, while during phase 4, a further three AF patients were identified by AFinder only. The AFinder web-based software, applied on top of standard in-hospital and remote monitoring, improved AF detection and enabled OAC treatment to be undertaken. ©2014 Wiley Periodicals, Inc.

Artificial Intelligence Methods Applied to Parameter Detection of Atrial Fibrillation

NASA Astrophysics Data System (ADS)

Arotaritei, D.; Rotariu, C.

2015-09-01

In this paper we present a novel method to develop an atrial fibrillation (AF) based on statistical descriptors and hybrid neuro-fuzzy and crisp system. The inference of system produce rules of type if-then-else that care extracted to construct a binary decision system: normal of atrial fibrillation. We use TPR (Turning Point Ratio), SE (Shannon Entropy) and RMSSD (Root Mean Square of Successive Differences) along with a new descriptor, Teager- Kaiser energy, in order to improve the accuracy of detection. The descriptors are calculated over a sliding window that produce very large number of vectors (massive dataset) used by classifier. The length of window is a crisp descriptor meanwhile the rest of descriptors are interval-valued type. The parameters of hybrid system are adapted using Genetic Algorithm (GA) algorithm with fitness single objective target: highest values for sensibility and sensitivity. The rules are extracted and they are part of the decision system. The proposed method was tested using the Physionet MIT-BIH Atrial Fibrillation Database and the experimental results revealed a good accuracy of AF detection in terms of sensitivity and specificity (above 90%).

Atrial fibrillation is not uncommon among patients with ischemic stroke and transient ischemic stroke in China.

PubMed

Yang, Xiaomeng; Li, Shuya; Zhao, Xingquan; Liu, Liping; Jiang, Yong; Li, Zixiao; Wang, Yilong; Wang, Yongjun

2017-12-04

Atrial fibrillation (AF) is reported to be a less frequent cause of ischemic stroke in China than in Europe and North America, but it is not clear whether this is due to underestimation. Our aim was to define the true frequency of AF-associated stroke, to determine the yield of 6-day Holter ECG to detect AF in Chinese stroke patients, and to elucidate predictors of newly detected AF. Patients with acute ischemic stroke or transient ischemic attack (TIA) were enrolled in a prospective, multicenter cohort study of 6-day Holter monitoring within 7 days after stroke onset at 20 sites in China between 2013 and 2015. Independent predictors of newly-detected AF were determined by multivariate analysis. Among 1511 patients with ischemic stroke and TIA (mean age 63 years, 33.1% women), 305 (20.2%) had either previously known (196, 13.0%) or AF newly-detected by electrocardiography (53, 3.5%) or by 6-day Holter monitoring (56/1262, 4.4%). A history of heart failure (OR = 4.70, 95%CI, 1.64-13.5), advanced age (OR = 1.06, 95%CI, 1.04-1.09), NIHSS at admission (OR = 1.06, 95%CI, 1.02-1.10), blood high density lipoprotein (HDL) (OR = 1.52, 95%CI, 1.09-2.13), together with blood triglycerides (OR = 0.64, 95%CI, 0.45-0.91) were independently associated with newly-detected AF. Contrary to previous reports, AF-associated stroke is frequent (20%) in China if systemically sought. Prolonged noninvasive cardiac rhythm monitoring importantly increases AF detection in patients with recent ischemic stroke and TIA in China. Advanced age, history of heart failure, and higher admission NIHSS and higher level of HDL were independent indicators of newly-detected AF. NCT02156765 (June 5, 2014).

[Primary Study on Predicting the Termination of Paroxysmal Atrial Fibrillation Based on a Novel RdR RR Intervals Scatter Plot].

PubMed

Lu, Hongwei; Zhang, Chenxi; Sun, Ying; Hao, Zhidong; Wang, Chunfang; Tian, Jiajia

2015-08-01

Predicting the termination of paroxysmal atrial fibrillation (AF) may provide a signal to decide whether there is a need to intervene the AF timely. We proposed a novel RdR RR intervals scatter plot in our study. The abscissa of the RdR scatter plot was set to RR intervals and the ordinate was set as the difference between successive RR intervals. The RdR scatter plot includes information of RR intervals and difference between successive RR intervals, which captures more heart rate variability (HRV) information. By RdR scatter plot analysis of one minute RR intervals for 50 segments with non-terminating AF and immediately terminating AF, it was found that the points in RdR scatter plot of non-terminating AF were more decentralized than the ones of immediately terminating AF. By dividing the RdR scatter plot into uniform grids and counting the number of non-empty grids, non-terminating AF and immediately terminating AF segments were differentiated. By utilizing 49 RR intervals, for 20 segments of learning set, 17 segments were correctly detected, and for 30 segments of test set, 20 segments were detected. While utilizing 66 RR intervals, for 18 segments of learning set, 16 segments were correctly detected, and for 28 segments of test set, 20 segments were detected. The results demonstrated that during the last one minute before the termination of paroxysmal AF, the variance of the RR intervals and the difference of the neighboring two RR intervals became smaller. The termination of paroxysmal AF could be successfully predicted by utilizing the RdR scatter plot, while the predicting accuracy should be further improved.

Opportunistic screening of atrial fibrillation by automatic blood pressure measurement in the community.

PubMed

Omboni, Stefano; Verberk, Willem J

2016-04-12

Timely detection of atrial fibrillation (AF) may effectively prevent cardiovascular consequences. However, traditional diagnostic tools are either poorly reliable (pulse palpation) or not readily accessible (ECG) in general practice. We tested whether an automatic oscillometric blood pressure (BP) monitor embedded with an algorithm for AF detection might be effective for opportunistic screening of asymptomatic AF in the community. A community-based screening campaign in an unselected population to verify the feasibility of AF screening with a Microlife WatchBP Office BP monitor with a patented AFIB algorithm. When possible AF was detected (≥2 of 3 BP measurements reporting AF), a doctor immediately performed a single-lead ECG in order to confirm or exclude the presence of the arrhythmia. The main demographic and clinical data were also collected. 220 consecutive participants from an unselected sample of individuals in a small Italian community. Number of patients detected with AF and diagnosed risk factors for AF. In 12 of 220 participants, the device detected possible AF during the BP measurement: in 4 of them (1.8%), the arrhythmia was confirmed by the ECG. Patients with AF were more likely to be older (77.0±1.2 vs 57.2±15.2 years, p=0.010), obese (50.0 vs 14.4%, p=0.048) and to suffer from a cardiovascular disease (50.0 vs 10.6%, p=0.014) than patients without AF. Participants with a positive BP AF reading and non-AF arrhythmias (n=8) did not differ in their general characteristics from participants with a negative BP AF reading and were younger than patients with AF (mean age 56.4±14.8, p=0.027; 5 of 8 participants aged <65 years). Opportunistic screening of AF by BP measurement is feasible to diagnose this arrhythmia in unaware participants, particularly in those older than 65 years, who are the target patient group recommended by current AF screening guidelines. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Prevention of Atrial Fibrillation by Using Sarcoplasmic Reticulum Calcium ATPase Pump Overexpression in a Rabbit Model of Rapid Atrial Pacing.

PubMed

Wang, Hong Li; Zhou, Xian Hui; Li, Zhi Qiang; Fan, Ping; Zhou, Qi Na; Li, Yao Dong; Hou, Yue Mei; Tang, Bao Peng

2017-08-16

BACKGROUND Recent research suggests that abnormal Ca2+ handling plays a role in the occurrence and maintenance of atrial fibrillation (AF). Therefore, Ca2+ release and ingestion depend on properties of the ryanodine receptor (RyR) and sarcoplasmic reticulum Ca2+ATPase2a (SERCA2a). This study aimed to detect whether SERCA2a gene overexpression has a preventive effect on atrial fibrillation caused by rapid pacing right atrium. MATERIAL AND METHODS Forty-eight New Zealand white rabbits were randomly divided into a control group, AF group, AAV9/GFP group, and AAV9/SERCA2a group. The right atrium was rapidly paced at 600 beats/min for 30 days after an intraperitoneal injection of an adeno-associated virus expressing the SERCA2a gene and GFP. The AF induction rate and the effective refraction period (ERP) were measured after 0, 4, 8, 12, and 24 h of pacing. Western blot analysis was used to test for the expression of SERCA2a. Changes in atrial tissue structure were observed by H&E staining and electron microscopy. RESULTS The AF induction rate was higher in the AF groups than in the AAV9/SERCA2a group at different time points of pacing. After 12 h of pacing, ERP was significantly prolonged in the AAV9/SERCA2a group compared to the AF and AAV9/GFP groups (p<0.05). SERCA2a protein expression was significantly lower in the AF and AAV9/GFP groups compared to the control group (p<0.05), while expression was significantly higher in the AAV9/SERCA2a group than in the AF and AAV9/GFP groups (p<0.05). The myocardial structure of the AAV9/SERCA2a group was significantly improved compared with the AF group, indicating that SERCA2a overexpression relieved the structural remodeling of atrial fibrillation. CONCLUSIONS SERCA2a overexpression is capable of suppressing ERP shortening and AF induced by rapid pacing atrium. SERCA2a gene therapy is expected to be a new anti-atrial fibrillation strategy.

Automated measurement of office, home and ambulatory blood pressure in atrial fibrillation.

PubMed

Kollias, Anastasios; Stergiou, George S

2014-01-01

1. Hypertension and atrial fibrillation (AF) often coexist and are strong risk factors for stroke. Current guidelines for blood pressure (BP) measurement in AF recommend repeated measurements using the auscultatory method, whereas the accuracy of the automated devices is regarded as questionable. This review presents the current evidence on the feasibility and accuracy of automated BP measurement in the presence of AF and the potential for automated detection of undiagnosed AF during such measurements. 2. Studies evaluating the use of automated BP monitors in AF are limited and have significant heterogeneity in methodology and protocols. Overall, the oscillometric method is feasible for static (office or home) and ambulatory use and appears to be more accurate for systolic than diastolic BP measurement. 3. Given that systolic hypertension is particularly common and important in the elderly, the automated BP measurement method may be acceptable for self-home and ambulatory monitoring, but not for professional office or clinic measurement. 4. An embedded algorithm for the detection of asymptomatic AF during routine automated BP measurement with high diagnostic accuracy has been developed and appears to be a useful screening tool for elderly hypertensives. © 2013 Wiley Publishing Asia Pty Ltd.

Insertable cardiac monitors in the diagnosis of syncope and the detection of atrial fibrillation: A systematic review and meta-analysis.

PubMed

Burkowitz, Jörg; Merzenich, Carina; Grassme, Kathrin; Brüggenjürgen, Bernd

2016-08-01

Insertable or implantable cardiac monitors (ICMs) continuously monitor the heart rhythm and record irregularities over 3 years, enabling the diagnosis of infrequent rhythm abnormalities associated with syncope and stroke. The enhanced recognition capabilities of recent ICM models are able to accurately detect atrial fibrillation (AF) and have led to new applications of ICMs for the detection and monitoring of AF. Based on a systematic literature search, two indications were identified for ICMs for which considerable evidence, including randomized studies, exists: diagnosing the underlying cardiac cause of unexplained recurrent syncope and detecting AF in patients after cryptogenic stroke (CS). Three randomized controlled trials (RCTs) were identified that compared the effectiveness of ICMs in diagnosing patients with unexplained syncope (n = 556) to standard of care. A meta-analysis was conducted in order to generate an overall effect size and confidence interval of the diagnostic yield of ICMs versus conventional monitoring. In the indication CS, one RCT and five observational studies were included in order to assess the performance of ICMs in diagnosing patients with AF (n = 1129). Based on these studies, there is strong evidence that ICMs provide a higher diagnostic yield for detecting arrhythmias in patients with unexplained syncope and for detection of AF in patients after CS compared to conventional monitoring. Prolonged monitoring with ICMs is an effective tool for diagnosing the underlying cardiac cause of unexplained syncope and for detecting AF in patients with CS. In all RCTs, ICMs have a superior diagnostic yield compared to conventional monitoring. © The European Society of Cardiology 2016.

Comparison of the Microlife blood pressure monitor with the Omron blood pressure monitor for detecting atrial fibrillation.

PubMed

Wiesel, Joseph; Arbesfeld, Benjamin; Schechter, David

2014-10-01

Screening for atrial fibrillation (AF) by assessing the pulse is recommended in high-risk patients. Some clinical trials demonstrated that the Microlife blood pressure monitor (BPM) with AF detection is more accurate than pulse palpation. This led to a change in practice guidelines in the United Kingdom where AF screening with the Microlife device is recommended instead of pulse palpation. Many BPMs have irregular heart beat detection, but they have not been shown to detect AF reliably. Recently, one study, in a highly select population, suggested that the Omron BPM with irregular heart beat detection has a higher sensitivity for AF than the Microlife BPM. We compared the Microlife and Omron BPMs to electrocardiographic readings for AF detection in general cardiology patients. Inclusion criteria were age≥50 years without a pacemaker or defibrillator. A total of 199 subjects were enrolled, 30 with AF. Each subject had a 12-lead electrocardiography, 1 Omron BPM reading, and 3 Microlife BPM readings as per device instructions. The Omron device had a sensitivity of 30% (95% confidence interval [CI] 15.4% to 49.1%) with the sensitivity for the first Microlife reading of 97% (95% CI 81.4% to 100%) and the Microlife readings using the majority rule (AF positive if at least 2 of 3 individual readings were positive for AF) of 100% (95% CI 85.9% to 100%). Specificity for the Omron device was 97% (95% CI 92.5% to 99.2%) and for the first Microlife reading of 90% (95% CI 83.8% to 94.2%) and for the majority rule Microlife device of 92% (95% CI 86.2% to 95.7%; p<0.0001). The specificity of both devices is acceptable, but only the Microlife BPM has a sensitivity value that is high enough to be used for AF screening in clinical practice. Copyright © 2014 Elsevier Inc. All rights reserved.

Identification of Left Atrial Appendage Thrombi in Patients With Persistent and Long-Standing Persistent Atrial Fibrillation Using Intra-Cardiac Echocardiography and Cardiac Computed Tomography.

PubMed

Ikegami, Yukinori; Tanimoto, Kojiro; Inagawa, Kohei; Shiraishi, Yasuyuki; Fuse, Jun; Sakamoto, Munehisa; Momiyama, Yukihiko; Takatsuki, Seiji

2017-12-25

Intracardiac echocardiography (ICE) and cardiac computed tomography (CCT), in addition to standard transesophageal echocardiography (TEE), have been used to identify left atrial (LA) thrombi prior to ablation for atrial fibrillation (AF). The clinical advantages of this, however, remain unclear. This study therefore investigated the advantages of additional pre-procedural LA appendage (LAA) thrombus evaluation using ICE and the clinical value of CCT in persistent and long-standing persistent AF.Methods and Results:We analyzed data from 108 consecutive patients with persistent and long-standing persistent AF who were scheduled to undergo AF ablation. TEE was performed within 24 h prior to ablation. ICE was performed for 97 patients in whom a thrombus was not detected on TEE. CCT was performed in 95 patients. Thrombus or sludge was detected on TEE in 11 patients (10.3%), for whom ablation was cancelled. Four additional patients were diagnosed with LAA thrombus on ICE. When TEE and ICE were used as the reference for thrombus detection, the sensitivity, specificity, positive predictive value, and negative predictive value of CCT for identifying contrast defects in the LAA were 100%, 81.0%, 40.7%, and 100%, respectively. ICE combined with TEE increased the detection rate of LAA thrombi in patients with persistent and long-standing persistent AF. Moreover, CCT had high sensitivity and negative predictive value for LAA thrombus detection.

The Impact of Transforming Growth Factor-β1 Level on Outcome After Catheter Ablation in Patients With Atrial Fibrillation.

PubMed

Kishima, Hideyuki; Mine, Takanao; Takahashi, Satoshi; Ashida, Kenki; Ishihara, Masaharu; Masuyama, Tohru

2017-04-01

Transforming growth factor-β 1 (TGF-β 1 ) is an important factor that induces atrial fibrosis and atrial fibrillation (AF). The purpose of this study was to evaluate the association between TGF-β 1 level and clinical factors before catheter ablation (CA), and to investigate the impact of TGF-β 1 level on the outcome after CA for AF. This prospective study included 151 patients (persistent AF group: n = 59, paroxysmal AF [PAF] group: n = 54, and control group: n = 38). All patients who underwent CA for AF were followed up for 12 months. The PAF group had the highest TGF-β 1 levels in all patients. An early recurrence of AF (ERAF: defined as episodes of atrial tachyarrhythmia within a 3-month blanking period) was detected in 60 patients (53%). Recurrent AF after the blanking period was detected in 36 patients (32%). On multivariate analysis, low TGF-β 1 level was the only independent factor associated with recurrent AF. Moreover, the AF recurrence ratio was higher in the low TGF-β 1 group (< 12.56 ng/mL) than in the high TGF-β 1 group (16 of 29 patients, 55% vs. 20 of 84 patients, 24%, P = 0.002 by log-rank test). PAF was associated with a higher TGF-β 1 level. Moreover, lower TGF-β 1 level in AF patients could be a cause of recurrent AF after CA. © 2017 Wiley Periodicals, Inc.

Comparison of Microlife BP A200 Plus and Omron M6 blood pressure monitors to detect atrial fibrillation in hypertensive patients.

PubMed

Marazzi, Giuseppe; Iellamo, Ferdinando; Volterrani, Maurizio; Lombardo, Mauro; Pelliccia, Francesco; Righi, Daniela; Grieco, Fabrizia; Cacciotti, Luca; Iaia, Luigi; Caminiti, Giuseppe; Rosano, Giuseppe

2012-01-01

Self-monitoring home blood pressure (BP) devices are currently recommended for long-term follow-up of hypertension and its management. Some of these devices are integrated with algorithms aimed at detecting atrial fibrillation (AF), which is common essential hypertension. This study was designed to compare the diagnostic accuracy of two widely diffused home BP monitoring devices in detecting AF in an unselected population of outpatients referred to a hypertension clinic because of high BP. In 503 consecutive patients the authors simultaneously compared the accuracy of the Microlife(®) BP A200 Plus (Microlife) and the OMRON(®) M6 (OMRON) home BP devices, in detecting AF. Systolic and diastolic BP as well as heart rate (HR) values detected by the two devices were not significantly different. Pulse irregularity was detected in 124 and 112 patients with the OMRON M6 and Microlife BP A200 Plus devices, respectively. Simultaneous electrocardiogram (ECG) recording revealed that pulse irregularity was due to AF in 101 patients. Pulse irregularity detected by the OMRON M6 device corresponded to AF in 101, to supraventricular premature beats in 18, and to frequent premature ventricular beat in five patients, respectively. Pulse irregularity detected by the Microlife BP A200 Plus device corresponded to AF in 93, to supraventricular premature beats in 14, and to ventricular premature beats in five patients. The sensitivity for detecting AF was 100%, the specificity was 92%, and diagnostic accuracy 95% for the OMRON M6 and 100%, 92%, and 95 for the Microlife BP A200 Plus, respectively. AF was newly diagnosed by ECG recordings in 47 patients, and was detected in all patients by the OMRON device, and in 42 patients by the Microlife device. These results indicate that OMRON M6 is more accurate than Microlife BP A200 Plus in detecting AF in patients with essential hypertension. Widespread use of these devices in hypertensive patients could be of clinical benefit for the early diagnosis and treatment of this arrhythmia and related consequences.

Atrial fibrillation driver mechanisms: Insight from the isolated human heart.

PubMed

Csepe, Thomas A; Hansen, Brian J; Fedorov, Vadim V

2017-01-01

Although there have been great technological advances in the treatment of atrial fibrillation (AF), current therapies remain limited due to a narrow understanding of AF mechanisms in the human heart. This review will highlight our recent studies on explanted human hearts where we developed and employed a novel functional-structural mapping approach by integrating high-resolution simultaneous endo-epicardial and panoramic optical mapping with 3D gadolinium-enhanced MRI to define the spatiotemporal characteristics of AF drivers and their structural substrates. The results allow us to postulate that the primary mechanism of AF maintenance in human hearts is a limited number of localized intramural microanatomic reentrant AF drivers anchored to heart-specific 3D fibrotically insulated myobundle tracks, which may remain hidden to clinical single-surface electrode mapping. We suggest that ex vivo human heart studies, by using an integrated 3D functional and structural mapping approach, will help to reveal defining features of AF drivers as well as validate and improve clinical approaches to detect and target these AF drivers in patients with cardiac diseases. Copyright © 2016 Elsevier Inc. All rights reserved.

Finding atrial fibrillation in stroke patients: Randomized evaluation of enhanced and prolonged Holter monitoring--Find-AF(RANDOMISED) --rationale and design.

PubMed

Weber-Krüger, Mark; Gelbrich, Götz; Stahrenberg, Raoul; Liman, Jan; Kermer, Pawel; Hamann, Gerhard F; Seegers, Joachim; Gröschel, Klaus; Wachter, Rolf

2014-10-01

Detecting paroxysmal atrial fibrillation (AF) in patients with ischemic strokes presenting in sinus rhythm is challenging because episodes are often short, occur randomly, and are frequently asymptomatic. If AF is detected, recurrent thromboembolism can be prevented efficiently by oral anticoagulation. Numerous uncontrolled studies using various electrocardiogram (ECG) devices have established that prolonged ECG monitoring increases the yield of AF detection, but most established procedures are time-consuming and costly. The few randomized trials are mostly limited to cryptogenic strokes. The optimal method, duration, and patient selection remain unclear. Repeated prolonged continuous Holter ECG monitoring to detect paroxysmal AF within an unspecific stroke population may prove to be a widely applicable, effective secondary prevention strategy. Find-AFRANDOMISED is a randomized and controlled prospective multicenter trial. Four hundred patients 60 years or older with manifest (symptoms ≥24 hours or acute computed tomography/magnetic resonance imaging lesion) and acute (symptoms ≤7 days) ischemic strokes will be included at 4 certified stroke centers in Germany. Those with previously diagnosed AF/flutter, indications/contraindications for oral anticoagulation, or obvious causative blood vessel pathologies will be excluded. Patients will be randomized 1:1 to either enhanced and prolonged Holter ECG monitoring (10 days at baseline and after 3 and 6 months) or standard of care (≥24-hour continuous ECG monitoring, according to current stroke guidelines). All patients will be followed up for at least 12 months. The primary end point is newly detected AF (≥30 seconds) after 6 months, confirmed by an independent adjudication committee. We plan to complete recruitment in autumn 2014. First results can be expected by spring 2016. Copyright © 2014 Mosby, Inc. All rights reserved.

Association between Embolic Stroke Patterns, ESUS Etiology, and New Diagnosis of Atrial Fibrillation: A Secondary Data Analysis of the Find-AF Trial

PubMed Central

Schregel, Katharina; Karch, André; Weber-Krueger, Mark; Stahrenberg, Raoul; Gröschel, Klaus; Knauth, Michael; Psychogios, Marios-Nikos; Wachter, Rolf; Liman, Jan

2017-01-01

Background. Atrial fibrillation (AF) is an important cause of embolic stroke of undetermined source (ESUS). Imaging-patterns like multiple infarcts, simultaneous involvement of different circulations, infarcts of different ages, and isolated cortical infarcts are likely to indicate cardioembolic stroke. The aim of our study was to evaluate the association between embolic stroke patterns, ESUS, and the new diagnosis of AF. Methods. Stroke etiology and imaging characteristics from patients included in the Find-AF study were obtained. Embolic stroke patterns in CT- or MR-imaging were correlated with the diagnosis of ESUS as well as the short- (on baseline ECG and during 7-day Holter) and long-term (12-month follow-up) diagnosis of AF. Results. From 281 patients included in the Find-AF study, 127 (45.2%) patients with ischemic lesions detected in CT or MRI were included. 26 (20.5%) of these patients had ESUS. At least one embolic stroke pattern was detected in 67 (52.7%) patients. Embolic stroke patterns were not associated with ESUS (OR 1.57, 0.65–3.79, p = 0.317), the short-term (OR 0.64, 0.26–1.58, p = 0.327) or long-term diagnosis of AF (OR 0.72, 0.31–1.68, p = 0.448). Conclusions. This secondary data analysis of the Find-AF study could not provide evidence for an association between embolic stroke patterns, ESUS, and the new diagnosis of AF. PMID:28536667

Association between Embolic Stroke Patterns, ESUS Etiology, and New Diagnosis of Atrial Fibrillation: A Secondary Data Analysis of the Find-AF Trial.

PubMed

Maier, Ilko L; Schregel, Katharina; Karch, André; Weber-Krueger, Mark; Mikolajczyk, Rafael T; Stahrenberg, Raoul; Gröschel, Klaus; Bähr, Mathias; Knauth, Michael; Psychogios, Marios-Nikos; Wachter, Rolf; Liman, Jan

2017-01-01

Background . Atrial fibrillation (AF) is an important cause of embolic stroke of undetermined source (ESUS). Imaging-patterns like multiple infarcts, simultaneous involvement of different circulations, infarcts of different ages, and isolated cortical infarcts are likely to indicate cardioembolic stroke. The aim of our study was to evaluate the association between embolic stroke patterns, ESUS, and the new diagnosis of AF. Methods . Stroke etiology and imaging characteristics from patients included in the Find-AF study were obtained. Embolic stroke patterns in CT- or MR-imaging were correlated with the diagnosis of ESUS as well as the short- (on baseline ECG and during 7-day Holter) and long-term (12-month follow-up) diagnosis of AF. Results . From 281 patients included in the Find-AF study, 127 (45.2%) patients with ischemic lesions detected in CT or MRI were included. 26 (20.5%) of these patients had ESUS. At least one embolic stroke pattern was detected in 67 (52.7%) patients. Embolic stroke patterns were not associated with ESUS (OR 1.57, 0.65-3.79, p = 0.317), the short-term (OR 0.64, 0.26-1.58, p = 0.327) or long-term diagnosis of AF (OR 0.72, 0.31-1.68, p = 0.448). Conclusions . This secondary data analysis of the Find-AF study could not provide evidence for an association between embolic stroke patterns, ESUS, and the new diagnosis of AF.

Impact of acute atrial fibrillation termination and prolongation of atrial fibrillation cycle length on the outcome of ablation of persistent atrial fibrillation: A substudy of the STAR AF II trial.

PubMed

Kochhäuser, Simon; Jiang, Chen-Yang; Betts, Timothy R; Chen, Jian; Deisenhofer, Isabel; Mantovan, Roberto; Macle, Laurent; Morillo, Carlos A; Haverkamp, Wilhelm; Weerasooriya, Rukshen; Albenque, Jean-Paul; Nardi, Stefano; Menardi, Endrj; Novak, Paul; Sanders, Prashanthan; Verma, Atul

2017-04-01

Controversy exists about the impact of acute atrial fibrillation (AF) termination and prolongation of atrial fibrillation cycle length (AFCL) during ablation on long-term procedural outcome. The purpose of this study was to analyze the influence of AF termination and AFCL prolongation on freedom from AF in patients from the STAR AF II (Substrate and Trigger Ablation for Reduction of Atrial Fibrillation Trial-Part II) trial. Acute changes in AFCL and AF termination were collected during the index procedure of the STAR AF II trial and compared to recurrence of AF at 18 months. Recurrence was assessed by ECG, Holter (3, 6, 9, 12, 18 months), and weekly transtelephonic ECG monitoring for 18 months. AF terminated in 8% of the pulmonary vein isolation (PVI) arm, 45% in the PVI+complex electrogram arm, and 22% of the PVI+linear ablation arm (P <.001), but freedom from AF did not differ among the 3 groups (P = .15). Freedom from AF was significantly higher in patients who presented to the laboratory in sinus rhythm (SR) compared to those without AF termination (63% vs 44%, P = .007). Patients with AF termination had an intermediate outcome (53%) that was not significantly different from those in SR (P = .84) or those who did not terminate (P = .08). AF termination was a univariable predictor of success (P = .007), but by multivariable analysis, presence of early SR was the strongest predictor of success (hazard ratio 0.67, P = .004). Prolongation of AFCL was not predictive of 18-month freedom from AF. Acute AF termination and prolongation in AFCL did not consistently predict 18-month freedom from AF. Presence of SR before or early during the ablation was the strongest predictor of better outcome. Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Feasibility of Using Mobile ECG Recording Technology to Detect Atrial Fibrillation in Low-Resource Settings.

PubMed

Evans, Grahame F; Shirk, Arianna; Muturi, Peter; Soliman, Elsayed Z

2017-12-01

Screening for atrial fibrillation (AF), a major risk factor for stroke that is on the rise in Africa, is becoming increasingly critical. This study sought to examine the feasibility of using mobile electrocardiogram (ECG) recording technology to detect AF. In this prospective observational study, we used a mobile ECG recorder to screen 50 African adults (66% women; mean age 54.3 ± 20.5 years) attending Kijabe Hospital (Kijabe, Kenya). Five hospital health providers involved in this study's data collection process also completed a self-administered survey to obtain information on their access to the Internet and mobile devices, both factors necessary to implement ECG mobile technology. Outcome measures included feasibility (completion of the study and recruitment of the patients on the planned study time frame) and the yield of the screening by the mobile ECG technology (ability to detect previously undiagnosed AF). Patients were recruited in a 2-week period as planned; only 1 of the 51 patients approached refused to participate (98% acceptance rate). All of the 50 patients who agreed to participate completed the test and produced readable ECGs (100% study completion rate). ECG tracings of 4 of the 50 patients who completed the study showed AF (8% AF yield), and none had been previously diagnosed with AF. When asked about continuous access to Internet and personal mobile devices, almost all of the health care providers surveyed answered affirmatively. Using mobile ECG technology in screening for AF in low-resource settings is feasible, and can detect a significant proportion of AF cases that will otherwise go undiagnosed. Further study is needed to examine the cost-effectiveness of this approach for detection of AF and its effect on reducing the risk of stroke in developing countries. Copyright © 2016 World Heart Federation (Geneva). Published by Elsevier B.V. All rights reserved.

Voxelwise distribution of acute ischemic stroke lesions in patients with newly diagnosed atrial fibrillation: Trigger of arrhythmia or only target of embolism?

PubMed Central

Johnson, Timothy D.; Dittgen, Felix; Nichols, Thomas E.; Malzahn, Uwe; Veltkamp, Roland

2017-01-01

Objective Atrial fibrillation (AF) is frequently detected after ischemic stroke for the first time, and brain regions involved in autonomic control have been suspected to trigger AF. We examined whether specific brain regions are associated with newly detected AF after ischemic stroke. Methods Patients with acute cerebral infarctions on diffusion-weighted magnetic resonance imaging were included in this lesion mapping study. Lesions were mapped and modeled voxelwise using Bayesian Spatial Generalised Linear Mixed Modeling to determine differences in infarct locations between stroke patients with new AF, without AF and with AF already known before the stroke. Results 582 patients were included (median age 68 years; 63.2% male). AF was present in 109/582 patients [(18.7%); new AF: 39/109 (35.8%), known AF: 70/109 (64.2%)]. AF patients had larger infarct volumes than patients without AF (mean: 29.7 ± 45.8 ml vs. 15.2 ± 35.1 ml; p<0.001). Lesions in AF patients accumulated in the right central middle cerebral artery territory. Increasing stroke size predicted progressive cortical but not pontine and thalamic involvement. Patients with new AF had more frequently lesions in the right insula compared to patients without AF when stroke size was not accounted for, but no specific brain region was more frequently involved after adjustment for infarct volume. Controlled for stroke size, left parietal involvement was less likely for patients with new AF than for those without AF or with known AF. Conclusions In the search for brain areas potentially triggering cardiac arrhythmias infarct size should be accounted for. After controlling for infarct size, there is currently no evidence that ischemic stroke lesions of specific brain areas are associated with new AF compared to patients without AF. This challenges the neurogenic hypothesis of AF according to which a relevant proportion of new AF is triggered by ischemic brain lesions of particular locations. PMID:28542605

Biomarkers of Atrial Cardiopathy and Atrial Fibrillation Detection on Mobile Outpatient Continuous Telemetry After Embolic Stroke of Undetermined Source.

PubMed

Sebasigari, Denise; Merkler, Alexander; Guo, Yang; Gialdini, Gino; Kummer, Benjamin; Hemendinger, Morgan; Song, Christopher; Chu, Antony; Cutting, Shawna; Silver, Brian; Elkind, Mitchell S V; Kamel, Hooman; Furie, Karen L; Yaghi, Shadi

2017-06-01

Biomarkers of atrial dysfunction or "cardiopathy" are associated with embolic stroke risk. However, it is unclear if this risk is mediated by undiagnosed paroxysmal atrial fibrillation or flutter (AF). We aim to determine whether atrial cardiopathy biomarkers predict AF on continuous heart-rhythm monitoring after embolic stroke of undetermined source (ESUS). This was a single-center retrospective study including all patients with ESUS undergoing 30 days of ambulatory heart-rhythm monitoring to look for AF between January 1, 2013 and December 31, 2015. We reviewed medical records for clinical, radiographic, and cardiac variables. The primary outcome was a new diagnosis of AF detected during heart-rhythm monitoring. The primary predictors were atrial biomarkers: left atrial diameter on echocardiography, P-wave terminal force in electrocardiogram (ECG) lead V1, and P wave - R wave (PR) interval on ECG. A multiple logistic regression model was used to assess the relationship between atrial biomarkers and AF detection. Among 196 eligible patients, 23 (11.7%) were diagnosed with AF. In unadjusted analyses, patients with AF were older (72.4 years versus 61.4 years, P < .001) and had larger left atrial diameter (39.2 mm versus 35.7 mm, P = .03). In a multivariable model, the only predictor of AF was age ≥ 60 years (odds ratio, 3.0; 95% CI, 1.06-8.5; P = .04). Atrial biomarkers were weakly associated with AF after ESUS. This suggests that previously reported associations between these markers and stroke may reflect independent cardiac pathways leading to stroke. Prospective studies are needed to investigate these mechanisms. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Association of atrial fibrillation and cancer: Analysis from two large population-based case-control studies.

PubMed

Saliba, Walid; Rennert, Hedy S; Gronich, Naomi; Gruber, Stephen B; Rennert, Gad

2018-01-01

An association between atrial fibrillation (AF) and risk of cancer has been suggested in several studies, including prospective cohort studies. However, the magnitude and the temporal nature of this association remain unclear. Data from two large prospective population-based case-control studies, the Molecular Epidemiology of Colorectal Cancer (MECC, n = 8,383) and the Breast Cancer in Northern Israel Study (BCINIS, n = 11,608), were used to better understand the nature and temporality of a possible association between cancer diagnosis and AF events before and after cancer diagnosis. A case-control study approach was employed to study prior AF as a risk factor for cancer, and a cohort study approach was employed to study incident cancer as a risk factor for AF. AF was associated with a significant reduced odds of cancer as reflected in the case-control approach, with an adjusted OR = 0.77 (95% CI, 0.65-0.91), while cancer was not found to be significantly associated with elevated risk of AF in the cohort approach, with an adjusted HR = 1.10 (0.98-1.23). The immediate period (90 days) after an AF event was associated with a 1.85 times increased risk of cancer, and the immediate period after the diagnosis of cancer was associated with a 3.4 fold increased risk of AF. These findings probably reflect both the effect of acute transient conditions associated with new cancer diagnosis and detection bias. Similar results were identified with colorectal and breast cancer cases. Atrial fibrillation of longer than 90 days duration is associated with reduced odds of new cancer diagnosis. The results of this study suggest that an association observed in prior research may be due to instances related to cancer diagnosis and detection bias rather than a causal relationship. However, there may be bias in the sampling and residual confounding that distort the associations.

Diagnostic Accuracy of a Novel Mobile Phone Application for the Detection and Monitoring of Atrial Fibrillation.

PubMed

Rozen, Guy; Vaid, Jeena; Hosseini, Seyed Mohammadreza; Kaadan, M Ihsan; Rafael, Allon; Roka, Attila; Poh, Yukkee C; Poh, Ming-Zher; Heist, Edwin Kevin; Ruskin, Jeremy Neil

2018-05-15

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in adults, associated with significant morbidity, increased mortality, and rising health-care costs. Simple and available tools for the accurate detection of arrhythmia recurrence in patients after electrical cardioversion (CV) or ablation procedures for AF can help to guide therapeutic decisions. We conducted a prospective, single-center study to evaluate the accuracy of Cardiio Rhythm Mobile Application (CRMA) for AF detection. Patients >18 years of age who were scheduled for elective CV for AF were enrolled in the study. CRMA finger pulse recordings, utilizing an iPhone camera, were obtained before (pre-CV) and after (post-CV) the CV. The findings were validated against surface electrocardiograms. Ninety-eight patients (75.5% men), mean age of 67.7 ± 10.5 years, were enrolled. No electrocardiogram for validation was available in 1 case. Pre-CV CRMA readings were analyzed in 97 of the 98 patients. Post-CV CRMA readings were analyzed for 92 of 93 patients who underwent CV. One patient left before the recording was obtained. The Cardiio Rhythm Mobile Application correctly identified 94 of 101 AF recordings (93.1%) as AF and 80 of 88 non-AF recordings (90.1%) as non-AF. The sensitivity was 93.1% (95% confidence interval [CI] = 86.9% to 97.2%) and the specificity was 90.9% (95% CI = 82.9% to 96.0%). The positive predictive value was 92.2% (95% CI = 85.8% to 95.8%) and the negative predictive value was 92.0% (95% CI = 94.8% to 95.9%). In conclusion, the CRMA demonstrates promising potential in accurate detection and discrimination of AF from normal sinus rhythm in patients with a history of AF. Copyright © 2018 Elsevier Inc. All rights reserved.

Circulating miRNAs in acute new-onset atrial fibrillation and their target mRNA network.

PubMed

da Silva, Ananília Medeiros Gomes; de Araújo, Jéssica Nayara Góes; de Oliveira, Katiene Macêdo; Novaes, Ana Eloísa Melo; Lopes, Mariana Borges; de Sousa, Júlio César Vieira; Filho, Antônio Amorim de Araújo; Luchessi, André Ducati; de Rezende, Adriana Augusto; Hirata, Mário Hiroyuki; Silbiger, Vivian Nogueira

2018-04-20

MicroRNAs (miRNAs) are involved in the pathogenesis of atrial fibrillation (AF), acting on development and progression. Our pilot study investigated the expression of six miRNAs and their miRNA-mRNA interactions in patients with acute new-onset AF, well-controlled AF, and normal sinus rhythm (controls). Plasma of acute new-onset AF patients (n = 5) was collected in the emergency room when patients presented with irregular and fast-atrial fibrillation rhythm. Samples from well-controlled AF (n = 16) and control (n =  15) patients were collected during medical appointments following an ECG. Expression of miR-21, miR-133a, miR-133b, miR-150, miR-328, and miR-499 was analyzed by real-time PCR. Ingenuity Pathway Analysis and the TargetScan database identified the top 30 mRNA targets of these miRNA, seeking the miRNA-mRNA interactions in cardiovascular process. Increased expression of miR-133b (1.4-fold), miR-328 (2.0-fold), and miR-499 (2.3-fold) was observed in patients with acute new-onset AF, compared with well-controlled AF and control patients. Decreased expression of miR-21 was seen in patients with well-controlled AF compared to those with acute new-onset AF and controls (0.6-fold). The miRNA-mRNA interaction demonstrated that SMAD7 and FASLG genes were the targets of miR-21, miR-133b, and miR-499 and were directly related to AF, being involved in apoptosis and fibrosis. The miRNAs had different expression profiles dependent on the AF condition, with higher expression in the acute new-onset AF than well-controlled AF. Clinically, this may contribute to an effective assessment for patients, leading to early detection of AF and monitoring to reduce the risk of other serious cardiovascular events. © 2018 Wiley Periodicals, Inc.

Atrial Fibrillation Screening in Nonmetropolitan Areas Using a Telehealth Surveillance System With an Embedded Cloud-Computing Algorithm: Prospective Pilot Study

PubMed Central

Chen, Ying-Hsien; Hung, Chi-Sheng; Huang, Ching-Chang; Hung, Yu-Chien

2017-01-01

Background Atrial fibrillation (AF) is a common form of arrhythmia that is associated with increased risk of stroke and mortality. Detecting AF before the first complication occurs is a recognized priority. No previous studies have examined the feasibility of undertaking AF screening using a telehealth surveillance system with an embedded cloud-computing algorithm; we address this issue in this study. Objective The objective of this study was to evaluate the feasibility of AF screening in nonmetropolitan areas using a telehealth surveillance system with an embedded cloud-computing algorithm. Methods We conducted a prospective AF screening study in a nonmetropolitan area using a single-lead electrocardiogram (ECG) recorder. All ECG measurements were reviewed on the telehealth surveillance system and interpreted by the cloud-computing algorithm and a cardiologist. The process of AF screening was evaluated with a satisfaction questionnaire. Results Between March 11, 2016 and August 31, 2016, 967 ECGs were recorded from 922 residents in nonmetropolitan areas. A total of 22 (2.4%, 22/922) residents with AF were identified by the physician’s ECG interpretation, and only 0.2% (2/967) of ECGs contained significant artifacts. The novel cloud-computing algorithm for AF detection had a sensitivity of 95.5% (95% CI 77.2%-99.9%) and specificity of 97.7% (95% CI 96.5%-98.5%). The overall satisfaction score for the process of AF screening was 92.1%. Conclusions AF screening in nonmetropolitan areas using a telehealth surveillance system with an embedded cloud-computing algorithm is feasible. PMID:28951384

Treatment Guidelines of Atrial Fibrillation (AFib or AF)

MedlinePlus

... Artery Disease Venous Thromboembolism Aortic Aneurysm More Treatment Guidelines of Atrial Fibrillation (AFib or AF) Updated:Jun 28,2017 What are the treatment guidelines for atrial fibrillation? Medical guidelines are written by ...

Comprehensive risk reduction in patients with atrial fibrillation: emerging diagnostic and therapeutic options—a report from the 3rd Atrial Fibrillation Competence NETwork/European Heart Rhythm Association consensus conference

PubMed Central

Kirchhof, Paulus; Lip, Gregory Y.H.; Van Gelder, Isabelle C.; Bax, Jeroen; Hylek, Elaine; Kaab, Stefan; Schotten, Ulrich; Wegscheider, Karl; Boriani, Giuseppe; Brandes, Axel; Ezekowitz, Michael; Diener, Hans; Haegeli, Laurent; Heidbuchel, Hein; Lane, Deirdre; Mont, Luis; Willems, Stephan; Dorian, Paul; Aunes-Jansson, Maria; Blomstrom-Lundqvist, Carina; Borentain, Maria; Breitenstein, Stefanie; Brueckmann, Martina; Cater, Nilo; Clemens, Andreas; Dobrev, Dobromir; Dubner, Sergio; Edvardsson, Nils G.; Friberg, Leif; Goette, Andreas; Gulizia, Michele; Hatala, Robert; Horwood, Jenny; Szumowski, Lukas; Kappenberger, Lukas; Kautzner, Josef; Leute, Angelika; Lobban, Trudie; Meyer, Ralf; Millerhagen, Jay; Morgan, John; Muenzel, Felix; Nabauer, Michael; Baertels, Christoph; Oeff, Michael; Paar, Dieter; Polifka, Juergen; Ravens, Ursula; Rosin, Ludger; Stegink, W.; Steinbeck, Gerhard; Vardas, Panos; Vincent, Alphons; Walter, Maureen; Breithardt, Günter; Camm, A. John

2012-01-01

While management of atrial fibrillation (AF) patients is improved by guideline-conform application of anticoagulant therapy, rate control, rhythm control, and therapy of accompanying heart disease, the morbidity and mortality associated with AF remain unacceptably high. This paper describes the proceedings of the 3rd Atrial Fibrillation NETwork (AFNET)/European Heart Rhythm Association (EHRA) consensus conference that convened over 60 scientists and representatives from industry to jointly discuss emerging therapeutic and diagnostic improvements to achieve better management of AF patients. The paper covers four chapters: (i) risk factors and risk markers for AF; (ii) pathophysiological classification of AF; (iii) relevance of monitored AF duration for AF-related outcomes; and (iv) perspectives and needs for implementing better antithrombotic therapy. Relevant published literature for each section is covered, and suggestions for the improvement of management in each area are put forward. Combined, the propositions formulate a perspective to implement comprehensive management in AF. PMID:21791573

Detecting atrial fibrillation by deep convolutional neural networks.

PubMed

Xia, Yong; Wulan, Naren; Wang, Kuanquan; Zhang, Henggui

2018-02-01

Atrial fibrillation (AF) is the most common cardiac arrhythmia. The incidence of AF increases with age, causing high risks of stroke and increased morbidity and mortality. Efficient and accurate diagnosis of AF based on the ECG is valuable in clinical settings and remains challenging. In this paper, we proposed a novel method with high reliability and accuracy for AF detection via deep learning. The short-term Fourier transform (STFT) and stationary wavelet transform (SWT) were used to analyze ECG segments to obtain two-dimensional (2-D) matrix input suitable for deep convolutional neural networks. Then, two different deep convolutional neural network models corresponding to STFT output and SWT output were developed. Our new method did not require detection of P or R peaks, nor feature designs for classification, in contrast to existing algorithms. Finally, the performances of the two models were evaluated and compared with those of existing algorithms. Our proposed method demonstrated favorable performances on ECG segments as short as 5 s. The deep convolutional neural network using input generated by STFT, presented a sensitivity of 98.34%, specificity of 98.24% and accuracy of 98.29%. For the deep convolutional neural network using input generated by SWT, a sensitivity of 98.79%, specificity of 97.87% and accuracy of 98.63% was achieved. The proposed method using deep convolutional neural networks shows high sensitivity, specificity and accuracy, and, therefore, is a valuable tool for AF detection. Copyright © 2017 Elsevier Ltd. All rights reserved.

Expression of TGFbeta1 in pulmonary vein stenosis after radiofrequency ablation in chronic atrial fibrillation of dogs.

PubMed

Li, Shufeng; Li, Hongli; Mingyan, E; Yu, Bo

2009-02-01

The development of pulmonary vein stenosis has recently been described after radiofrequency ablation (RF) to treat atrial fibrillation (AF). The purpose of this study was to examine expression of TGFbeta1 in pulmonary vein stenosis after radiofrequency ablation in chronic atrial fibrillation of dogs. About 28 mongrel dogs were randomly assigned to the sham-operated group (n = 7), the AF group (n = 7), AF + RF group (n = 7), and RF group (n = 7). In AF or AF + RF groups, dogs underwent chronic pulmonary vein (PV) pacing to induce sustained AF. RF application was applied around the PVs until electrical activity was eliminated. Histological assessment of pulmonary veins was performed using hematoxylin and eosin staining; TGFbeta1 gene expression in pulmonary veins was examined by RT-PCR analysis; expression of TGFbeta1 protein in pulmonary veins was assessed by Western blot analysis. Rapid pacing from the left superior pulmonary vein (LSPV) induced sustained AF in AF group and AF + RF group. Pulmonary vein ablation terminated the chronic atrial fibrillation in dogs. Histological examination revealed necrotic tissues in various stages of collagen replacement, intimal thickening, and cartilaginous metaplasia with chondroblasts and chondroclasts. Compared with sham-operated and AF group, TGFbeta1 gene and protein expressions was increased in AF + RF or RF groups. It was concluded that TGFbeta1 might be associated with pulmonary vein stenosis after radiofrequency ablation in chronic atrial fibrillation of dogs.

Characteristics of atrial fibrillation cycle length predict restoration of sinus rhythm by catheter ablation.

PubMed

Di Marco, Luigi Yuri; Raine, Daniel; Bourke, John P; Langley, Philip

2013-09-01

Successful termination of atrial fibrillation (AF) during catheter ablation (CA) is associated with arrhythmia-free follow-up. Preablation factors such as mean atrial fibrillation cycle length (AFCL) predict the likelihood of AF termination during ablation but recurring patterns and AFCL stability have not been evaluated. To investigate novel predictors of acute and postoperative ablation outcomes from intracardiac electrograms: (1) recurring AFCL patterns and (2) localization index (LI) of the instantaneous fibrillatory rate distribution. Sixty-two patients with AF (32 paroxysmal AF; 45 men; age 57 ± 10 years) referred for CA were enrolled. One-minute electrogram was recorded from coronary sinus (CS; 5 bipoles) and right atrial appendage (HRA; 2 bipoles). Atrial activations were detected automatically to derive the AFCL and instantaneous fibrillatory rate (inverse of AFCL) time series. Recurring AFCL patterns were quantified by using recurrence plot indices (RPIs): percentage determinism, entropy of determinism, and maximum diagonal length. AFCL stability was determined by using the LI. The CA outcome predictivity of individual indices was assessed. Patients with terminated atrial fibrillation (T-AF) had higher RPI (P < .05 in CS7-8) and LI than did those with nonterminated atrial fibrillation (P < .005 in CS3-4; P < .05 in CS5-6, CS7-8, and HRA). Patients free of arrhythmia after 3-month follow-up had higher RPI and LI (all P < .05 in CS7-8). All indices except percentage determinism predicted T-AF in CS7-8 (area under the curve [AUC] ≥ 0.71; odds ratio [OR] ≥ 4.50; P < .05). The median AFCL and LI predicted T-AF in HRAD (AUC ≥ 0.75; OR ≥ 7.76; P < .05). The RPI and LI predicted 3-month follow-up in CS7-8 (AUC ≥ 0.68; OR ≥ 4.17; P < .05). AFCL recurrence and stability indices could be used in selecting patients more likely to benefit from CA. Copyright © 2013 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Management of atrial fibrillation in Greece: the MANAGE-AF study.

PubMed

Andrikopoulos, George; Pastromas, Sokratis; Mantas, Ioannis; Sakellariou, Dimitris; Kyrpizidis, Christos; Makridis, Pantelis; Goumas, Georgios; Stakos, Dimitris; Gotsis, Alexandros; Kartalis, Athanasios; Kazianis, Georgios; Babalis, Dimitrios; Toli, Konstantina; Tzeis, Stylianos; Papavasileiou, Maria; Kalogeropoulos, Petros; Vardas, Panos

2014-01-01

Although atrial fibrillation (AF) is a highly prevalent health problem with high morbidity and mortality, data regarding the clinical characteristics and management of AF in the Greek population are scarce. The "Current Clinical Practice in the MANAGEment of Atrial Fibrillation in Greece" study (MANAGEAF) aimed to assess the epidemiological features as well as the daily clinical practice in the management of Greek patients with AF. Taking into consideration the distribution of the Greek population, 603 consecutive patients over 18 years of age, with any type of AF, presenting at the emergency departments or outpatient clinics of 27 different centers, were included in our study. The mean age of the patients was 68.5 ± 12.1 years, with male patients representing 52.5% of the study population. The most common AF type in our cohort was non-paroxysmal AF (60%), including the patients with permanent (24.1%), persistent (17.4%), long-standing (4.8%) and first diagnosed AF (13.8%). Hypertension was the most common comorbidity (70.3%). A history of stroke or transient ischemic attack was detected in 9.2% of the patients, while 6.2% had a history of gastrointestinal bleeding. About half of the patients (49.3%) were treated with anticoagulant drugs, mainly vitamin K antagonists (46.9%), while 34.2% were on antiplatelet drugs, aspirin and/or clopidogrel. The mean INR level (1.7 ± 0.8) was sub-therapeutic, although the mean values for CHADS2 and CHA2DS2-VASc scores were 1.6 ± 1.2 and 3.0 ± 1.7, respectively. The MANAGE-AF baseline results indicate unsatisfactory levels of compliance with the current guidelines for the management of AF in Greece. Considering the undisputed effectiveness of anticoagulant treatment for preventing AF-related strokes, MANAGE-AF demonstrates the need for optimization of our therapeutic strategies for the management of cardioembolic stroke risk.

Heartbeat Cycle Length Detection by a Ballistocardiographic Sensor in Atrial Fibrillation and Sinus Rhythm

PubMed Central

Zink, Matthias Daniel; Brüser, Christoph; Winnersbach, Patrick; Napp, Andreas; Leonhardt, Steffen; Marx, Nikolaus; Schauerte, Patrick; Mischke, Karl

2015-01-01

Background. Heart rate monitoring is especially interesting in patients with atrial fibrillation (AF) and is routinely performed by ECG. A ballistocardiography (BCG) foil is an unobtrusive sensor for mechanical vibrations. We tested the correlation of heartbeat cycle length detection by a novel algorithm for a BCG foil to an ECG in AF and sinus rhythm (SR). Methods. In 22 patients we obtained BCG and synchronized ECG recordings before and after cardioversion and examined the correlation between heartbeat characteristics. Results. We analyzed a total of 4317 heartbeats during AF and 2445 during SR with a correlation between ECG and BCG during AF of r = 0.70 (95% CI 0.68–0.71, P < 0.0001) and r = 0.75 (95% CI 0.73–0.77, P < 0.0001) during SR. By adding a quality index, artifacts could be reduced and the correlation increased for AF to 0.76 (95% CI 0.74–0.77, P < 0.0001, n = 3468) and for SR to 0.85 (95% CI 0.83–0.86, P < 0.0001, n = 2176). Conclusion. Heartbeat cycle length measurement by our novel algorithm for BCG foil is feasible during SR and AF, offering new possibilities of unobtrusive heart rate monitoring. This trial is registered with IRB registration number EK205/11. This trial is registered with clinical trials registration number NCT01779674. PMID:26229965

Atrial Fibrillation Screening in Nonmetropolitan Areas Using a Telehealth Surveillance System With an Embedded Cloud-Computing Algorithm: Prospective Pilot Study.

PubMed

Chen, Ying-Hsien; Hung, Chi-Sheng; Huang, Ching-Chang; Hung, Yu-Chien; Hwang, Juey-Jen; Ho, Yi-Lwun

2017-09-26

Atrial fibrillation (AF) is a common form of arrhythmia that is associated with increased risk of stroke and mortality. Detecting AF before the first complication occurs is a recognized priority. No previous studies have examined the feasibility of undertaking AF screening using a telehealth surveillance system with an embedded cloud-computing algorithm; we address this issue in this study. The objective of this study was to evaluate the feasibility of AF screening in nonmetropolitan areas using a telehealth surveillance system with an embedded cloud-computing algorithm. We conducted a prospective AF screening study in a nonmetropolitan area using a single-lead electrocardiogram (ECG) recorder. All ECG measurements were reviewed on the telehealth surveillance system and interpreted by the cloud-computing algorithm and a cardiologist. The process of AF screening was evaluated with a satisfaction questionnaire. Between March 11, 2016 and August 31, 2016, 967 ECGs were recorded from 922 residents in nonmetropolitan areas. A total of 22 (2.4%, 22/922) residents with AF were identified by the physician's ECG interpretation, and only 0.2% (2/967) of ECGs contained significant artifacts. The novel cloud-computing algorithm for AF detection had a sensitivity of 95.5% (95% CI 77.2%-99.9%) and specificity of 97.7% (95% CI 96.5%-98.5%). The overall satisfaction score for the process of AF screening was 92.1%. AF screening in nonmetropolitan areas using a telehealth surveillance system with an embedded cloud-computing algorithm is feasible. ©Ying-Hsien Chen, Chi-Sheng Hung, Ching-Chang Huang, Yu-Chien Hung, Juey-Jen Hwang, Yi-Lwun Ho. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 26.09.2017.

Sudden cardiac death complicating newly diagnosed atrial fibrillation in the setting of subclinical hyperthyroidism.

PubMed

Mountantonakis, Stavros Emmanouil; Cruz Palma, Eugen

2008-01-01

Atrial fibrillation (AF) is the most common arrhythmia in clinical practice and a predictor of all-cause mortality. Subclinical hyperthyroidism is an independent risk factor for developing AF but its clinical significance in younger patients has not been established. We describe a clinical case of a 44-year-old female with newly diagnosed AF, degenerating to ventricular fibrillation in the setting of subclinical hyperthyroidism.

Survey of Antithrombotic Treatment in Rural Patients (>60 years) with Atrial Fibrillation in East China.

PubMed

Wei, Yong; Xu, Juan; Wu, Haiqing; Zhou, Genqing; Chen, Songwen; Wang, Caihong; Shen, Yahong; Yang, Shunhong; Wang, Bin; He, Zheng; Sun, Jianping; Sun, Weidong; Ouyang, Ping; Liu, Shaowen

2018-05-01

The prevalence and antithrombotic treatment of atrial fibrillation (AF) in Chinese rural population is not well known. The aim of this study was to investigate the extent to which antithrombotic treatment was prescribed for rural AF patients >60 years. We identified 828 AF patients from 36734 rural residents >60 years in Shanghai China. Our data indicated the overall prevalence rate of AF was 2.3% in rural population >60 years in East China and 38.9% of AF patients underwent antithrombotic therapy, including warfarin (5.9%), aspirin (29.6%), clopidogrel (2.9%) and aspirin combined with clopidogrel (0.5%). Of enrolled subjects, 98.4% had CHA 2 DS 2 -VASc score ≥1, 72.0% had HAS-BLED score <3 and 59.2% had CHA 2 DS 2 -VASc score ≥2 with HAS-BLED score <3. Missing early detection (34.9%), delay in seeking treatment for asymptomatic AF (25.5%) and doctors's incomplete inform of AF-related risk of stroke to patients (21.7%) were three dominant causes for failing anticoagulant usage. In conclusion, most AF patients were with a high risk of thrombosis and a low risk of bleeding in China, but a large majority of them failed to take anticoagulants mainly for missing an early screening of AF and lack of awareness on AF for both patients and primary care physicians.

Recurrent patterns of atrial depolarization during atrial fibrillation assessed by recurrence plot quantification.

PubMed

Censi, F; Barbaro, V; Bartolini, P; Calcagnini, G; Michelucci, A; Gensini, G F; Cerutti, S

2000-01-01

The aim of this study was to determine the presence of organization of atrial activation processes during atrial fibrillation (AF) by assessing whether the activation sequences are wholly random or are governed by deterministic mechanisms. We performed both linear and nonlinear analyses based on the cross correlation function (CCF) and recurrence plot quantification (RPQ), respectively. Recurrence plots were quantified by three variables: percent recurrence (PR), percent determinism (PD), and entropy of recurrences (ER). We recorded bipolar intra-atrial electrograms in two atrial sites during chronic AF in 19 informed subjects, following two protocols. In one, both recording sites were in the right atrium; in the other protocol, one site was in the right atrium, the other one in the left atrium. We extracted 19 episodes of type I AF (Wells' classification). RPQ detected transient recurrent patterns in all the episodes, while CCF was significant only in ten episodes. Surrogate data analysis, based on a cross-phase randomization procedure, decreased PR, PD, and ER values. The detection of spatiotemporal recurrent patterns together with the surrogate data results indicate that during AF a certain degree of local organization exists, likely caused by deterministic mechanisms of activation.

Atrial fibrillation detection using an iPhone 4S.

PubMed

Lee, Jinseok; Reyes, Bersain A; McManus, David D; Maitas, Oscar; Mathias, Oscar; Chon, Ki H

2013-01-01

Atrial fibrillation (AF) affects three to five million Americans and is associated with significant morbidity and mortality. Existing methods to diagnose this paroxysmal arrhythmia are cumbersome and/or expensive. We hypothesized that an iPhone 4S can be used to detect AF based on its ability to record a pulsatile photoplethysmogram signal from a fingertip using the built-in camera lens. To investigate the capability of the iPhone 4S for AF detection, we first used two databases, the MIT-BIH AF and normal sinus rhythm (NSR) to derive discriminatory threshold values between two rhythms. Both databases include RR time series originating from 250 Hz sampled ECG recordings. We rescaled the RR time series to 30 Hz so that the RR time series resolution is 1/30 (s) which is equivalent to the resolution from an iPhone 4S. We investigated three statistical methods consisting of the root mean square of successive differences (RMSSD), the Shannon entropy (ShE) and the sample entropy (SampE), which have been proved to be useful tools for AF assessment. Using 64-beat segments from the MIT-BIH databases, we found the beat-to-beat accuracy value of 0.9405, 0.9300, and 0.9614 for RMSSD, ShE, and SampE, respectively. Using an iPhone 4S, we collected 2-min pulsatile time series from 25 prospectively recruited subjects with AF pre- and postelectrical cardioversion. Using derived threshold values of RMSSD, ShE and SampE from the MIT-BIH databases, we found the beat-to-beat accuracy of 0.9844, 0.8494, and 0.9522, respectively. It should be recognized that for clinical applications, the most relevant objective is to detect the presence of AF in the data. Using this criterion, we achieved an accuracy of 100% for both the MIT-BIH AF and iPhone 4S databases.

Study protocol for Smartphone Monitoring for Atrial fibrillation in Real-Time in India (SMART-India): a community-based screening and referral programme

PubMed Central

Karna, Sunil; Patel, Harshil; Fahey, Nisha; Raithatha, Shyamsundar; Handorf, Anna; Bostrom, John; Bashar, Syed; Talati, Kandarp; Shah, Ravi; Goldberg, Robert J; Thanvi, Sunil; Allison, Jeroan J; Chon, Ki; Nimbalkar, Somashekhar Marutirao; McManus, David D

2017-01-01

Introduction Atrial fibrillation (AF), the world’s most common arrhythmia, often goes undetected and untreated in low-resource communities, including India, where AF epidemiology is undefined. AF is an important risk factor for stroke, which plagues an estimated 1.6 million Indians annually. As such, early detection of AF and management of high-risk patients is critically important to decrease stroke burden in individuals with AF. This study aims to describe the epidemiology of AF in Anand District, Gujarat, India, characterise the clinical profile of individuals who are diagnosed with AF and determine the performance of two mobile technologies for community-based AF screening. Methods This observational study builds on findings from a previous feasibility study and leverages two novel technologies as well as an existing community health programme to perform door-to-door AF screening for 2000 people from 60 villages of Anand District, Gujarat, India using local health workers. A single-lead ECG and a pulse-based application is used to screen each individual for AF three times over a period of 5 days. Participants with suspected arrhythmias are followed up by study cardiologist who makes final diagnoses. Participants diagnosed with AF are initiated on treatment based on current anticoagulation guidelines and clinical reasoning. Analytical plan Age-stratified and sex-stratified prevalence of AF in the Anand District will be calculated for sample and estimated for Anand distribution using survey design weights. Sociodemographic and clinical factors associated with AF will be evaluated using multivariable regression methods. Performance of each mobile technology in detecting AF will be evaluated using a 12-lead ECG interpretation as the gold standard. Ethics and dissemination This protocol was approved separately by the Institutional Review Board of University of Massachusetts Medical School and the Human Research Ethics Committee at Charutar Arogya Mandal. The findings of this study will be disseminated through peer-reviewed journals and scientific conferences. PMID:29247089

High pro-BNP levels predict the occurrence of atrial fibrillation after cryptogenic stroke.

PubMed

Rodríguez-Yáñez, Manuel; Arias-Rivas, Susana; Santamaría-Cadavid, María; Sobrino, Tomás; Castillo, José; Blanco, Miguel

2013-07-30

Antiplatelets are recommended for secondary prevention in patients with cryptogenic stroke; however, some patients may present with a cardioembolic source that has not been detected, which may modify the treatment. Because high pro-brain natriuretic peptide (BNP) levels are associated with cardioembolic stroke, our objective was to determine whether pro-BNP levels in the acute phase of stroke predict the development of atrial fibrillation (AF) in patients with cryptogenic stroke. A prospective study including patients with cryptogenic stroke was conducted. Demographic data, medical history, and stroke characteristics were assessed at admission. A blood sample was obtained within the first 24 hours from stroke onset to determine pro-BNP levels. Patients were followed by a neurologist at 3 and 6 months and later by a primary care physician for 2 years to evaluate the development of AF. One thousand fifty patients with ischemic stroke were evaluated. Three hundred seventy-two patients (35%) had cryptogenic stroke. One hundred eight patients were excluded from the study, so 264 patients were valid for the analysis. AF was detected in 15 patients (5.6%) during the follow-up. Patients who developed AF were older, had hypertension more frequently, and showed higher levels of pro-BNP. In the logistic regression model, we found that pro-BNP ≥360 pg/mL was the only variable independently associated with the risk of developing AF (odds ratio 5.70, 95% confidence interval 1.11-29.29, p = 0.037). Pro-BNP ≥360 pg/mL increases by 5-fold the possibility of detecting AF during follow-up in patients with cryptogenic stroke.

Multi-scale Structural and Tensile Mechanical Response of Annulus Fibrosus to Osmotic Loading

PubMed Central

Han, Woojin M.; Nerurkar, Nandan L.; Smith, Lachlan J.; Jacobs, Nathan T.; Mauck, Robert L.; Elliott, Dawn M.

2012-01-01

This study investigates differential multi-scale structure and function relationships of the outer and inner annulus fibrosus (AF) to osmotic swelling in different buffer solutions by quantifying tensile mechanics, GAG content, water content and tissue swelling, and collagen fibril ultrastructure. In the outer AF, the tensile modulus decreased by over 70% with 0.15M PBS treatment but was unchanged with 2M PBS treatment. Moreover, the modulus loss following 0.15M PBS treatment was reversed when followed by 2M PBS treatment, potentially from increased interfibrillar and interlamellar shearing associated with fibril swelling. In contrast, the inner AF tensile modulus was unchanged by 0.15M PBS treatment and increased following 2M treatment. Transmission electron microscopy revealed that the mean collagen fibril diameters of the untreated outer and inner AF were 87.8 ± 27.9 and 71.0 ± 26.9 nm, respectively. In the outer AF, collagen fibril swelling was observed with both 0.15M and 2M PBS treatments, but inherently low GAG content remained unchanged. In the inner AF, 2M PBS treatment caused fibril swelling and GAG loss, suggesting that GAG plays a role in maintaining the structure of collagen fibrils leading to modulation of the native tissue mechanical properties. These results demonstrate important regional variations in structure and composition, and their influence on the heterogeneous mechanics of the AF. Moreover, because the composition and structure is altered as a consequence of progressive disc degeneration, quantification of these interactions is critical for study of the AF pathogenesis of degeneration and tissue engineering. PMID:22314837

Investigation of atrial vulnerability by analysis of the sinus node EG from atrial fibrillation models using a phase synchronization method.

PubMed

Chen, Ying; Wu, Zhong; Yang, Cuiwei; Shao, Jun; Wong, Kelvin Kian Loong; Abbott, Derek

2012-09-01

Atrial fibrillation (AF) can result in life-threatening arrhythmia, and a clinically convenient means for detecting vulnerability remains elusive. We investigated atrial vulnerability by analyzing the sinus electrogram (EG) from AF animal models using a phase synchronization method. Using acetylcholine (ACh)-induced acute canine AF models (n= 4), a total of 128 electrical leads were attached to the surface of the anterior and posterior atria, and the pulmonary veins to form an electrocardiological mapping system. ACh was injected at varying concentrations with ladder-type adjustments. Sinus EGs and induced AF EGs that pertain to specific ACh concentrations were recorded.We hypothesize that the atrial vulnerability may be correlated with the Shannon entropy (SE) of the phase difference matrix that is extracted from the sinus EG. Our research suggests that the combination of SE with the synchronization method enables the sinus node EG to be analyzed and used to estimate atrial vulnerability.

Effect of Omega-3 Polyunsaturated Fatty Acid Supplementation in Patients with Atrial Fibrillation.

PubMed

Kumar, Sanjay; Qu, Sarah; Kassotis, John T

2012-01-01

Atrial fibrillation (AF) is the most common sustained atrial arrhythmia conferring a higher morbidity and mortality. Despite the increasing incidence of AF; available therapies are far from perfect. Dietary fish oils, containing omega 3 fatty acids, also called polyunsaturated fatty acid [PUFA] have demonstrated beneficial electrophysiological, autonomic and anti-inflammatory effects on both atrial and ventricular tissue. Multiple clinical trials, focusing on various subsets of patients with AF, have studied the role of PUFA and their potential role in reducing the incidence of this common arrhythmia. While PUFA appears to have a beneficial effect in the primary prevention of AF in the elderly with structural heart disease, this benefit has not been universally observed. In the secondary prevention of AF, PUFA seems to have a greater impact in the reducing AF in patients with paroxysmal or persistent AF, stages of AF associated with less atrial fibrosis and negative structural remodeling. However, AF suppression has not been consistently demonstrated in clinical trials. In patients undergoing heart surgery, increasing PUFA intake has yielded mixed results in terms of AF prevention post-operatively; however, increased PUFA has been associated with a reduction in hospital stay. Therefore recommending the use of PUFA for the purpose of AF reduction remains controversial. This is in part attributable to the complexity of AF. Other conflicting variables include: heterogeneous patient populations studied; variable dosing; duration of follow-up; comorbidities; and, concomitant pharmacotherapy. This review article reviews in detail available basic and clinical research studies of fish oil in the treatment of AF, and its role in the treatment of this common disorder. AF=Atrial fibrillation, CHS=Cardiovascular Health Study,CABG=Coronary artery bypass surgery, d=Day, DHA=Docosahexaenoic acid, EPA=Eicosapentaenoic acid, ERP= Effective refractory period, g=Gram, PAF= Paroxysmal atrial fibrillation, PeAF= Persistent atrial fibrillation PUFA= Polyunsaturated fatty acid.

Feasibility and cost-effectiveness of stroke prevention through community screening for atrial fibrillation using iPhone ECG in pharmacies. The SEARCH-AF study.

PubMed

Lowres, Nicole; Neubeck, Lis; Salkeld, Glenn; Krass, Ines; McLachlan, Andrew J; Redfern, Julie; Bennett, Alexandra A; Briffa, Tom; Bauman, Adrian; Martinez, Carlos; Wallenhorst, Christopher; Lau, Jerrett K; Brieger, David B; Sy, Raymond W; Freedman, S Ben

2014-06-01

Atrial fibrillation (AF) causes a third of all strokes, but often goes undetected before stroke. Identification of unknown AF in the community and subsequent anti-thrombotic treatment could reduce stroke burden. We investigated community screening for unknown AF using an iPhone electrocardiogram (iECG) in pharmacies, and determined the cost-effectiveness of this strategy.Pharmacists performedpulse palpation and iECG recordings, with cardiologist iECG over-reading. General practitioner review/12-lead ECG was facilitated for suspected new AF. An automated AF algorithm was retrospectively applied to collected iECGs. Cost-effectiveness analysis incorporated costs of iECG screening, and treatment/outcome data from a United Kingdom cohort of 5,555 patients with incidentally detected asymptomatic AF. A total of 1,000 pharmacy customers aged ≥65 years (mean 76 ± 7 years; 44% male) were screened. Newly identified AF was found in 1.5% (95% CI, 0.8-2.5%); mean age 79 ± 6 years; all had CHA2DS2-VASc score ≥2. AF prevalence was 6.7% (67/1,000). The automated iECG algorithm showed 98.5% (CI, 92-100%) sensitivity for AF detection and 91.4% (CI, 89-93%) specificity. The incremental cost-effectiveness ratio of extending iECG screening into the community, based on 55% warfarin prescription adherence, would be $AUD5,988 (€3,142; $USD4,066) per Quality Adjusted Life Year gained and $AUD30,481 (€15,993; $USD20,695) for preventing one stroke. Sensitivity analysis indicated cost-effectiveness improved with increased treatment adherence.Screening with iECG in pharmacies with an automated algorithm is both feasible and cost-effective. The high and largely preventable stroke/thromboembolism risk of those with newly identified AF highlights the likely benefits of community AF screening. Guideline recommendation of community iECG AF screening should be considered.

Baseline Demographics, Safety, and Patient Acceptance of an Insertable Cardiac Monitor for Atrial Fibrillation Screening: The REVEAL-AF Study.

PubMed

Conti, Sergio; Reiffel, James A; Gersh, Bernard J; Kowey, Peter R; Wachter, Rolf; Halperin, Jonathan L; Kaplon, Rachelle E; Pouliot, Erika; Verma, Atul

2017-01-01

Given the high prevalence and risk of stroke associated with atrial fibrillation (AF), detection strategies have important public health implications. The ongoing prospective, single-arm, open-label, multicenter REVEAL AF trial is evaluating the incidence of previously undetected AF using an insertable cardiac monitor (ICM) in patients without prior AF or device implantation, but who could be at risk for AF due to their demographic characteristics, +/- non-specific but compatible symptoms. Enrollment required an elevated AF risk profile defined as CHADS2≥3 or CHADS 2 =2 plus one or more of the following: coronary artery disease, renal impairment, sleep apnea or chronic obstructive pulmonary disease. Exclusions included stroke or transient ischemic attack occurring in the previous year. Of 450 subjects screened, 399 underwent a device insertion attempt, and 395 were included in the final analysis (Reveal XT: n=122; Reveal LINQ: n=273; excluded: n=4). Participants were primarily identified by demographic characteristics and the presence of nonspecific symptoms, but without prior documentation of "overt" AF. The most common symptoms were palpitations (51%), dizziness/lightheadedness/pre-syncope (36%), and shortness of breath (36%). Over 100 subjects were enrolled in each pre-defined CHADS2 subgroup (2, 3 and ≥4). AF risk factors not included in the CHADS2 score were well represented (prevalence≥15%). Procedure and/or device related serious adverse events were low, with the miniaturized Reveal LINQ ICM having a more favorable safety profile than the predicate Reveal XT (all: n=13 [3.3%]; LINQ: n=6 [2.2%]; XT: n=7 [5.7%]). These data demonstrate that REVEAL AF was successful in enrolling its target population, high risk patients were willing to undergo ICM monitoring for AF screening, and ICM use in this group is becoming increasingly safe with advancements in technology. A clinically meaningful incidence of device detected AF in this study will inform clinical decisions regarding ICM use for AF screening in patients at risk.

Diagnostic Performance of a Smartphone-Based Photoplethysmographic Application for Atrial Fibrillation Screening in a Primary Care Setting.

PubMed

Chan, Pak-Hei; Wong, Chun-Ka; Poh, Yukkee C; Pun, Louise; Leung, Wangie Wan-Chiu; Wong, Yu-Fai; Wong, Michelle Man-Ying; Poh, Ming-Zher; Chu, Daniel Wai-Sing; Siu, Chung-Wah

2016-07-21

Diagnosing atrial fibrillation (AF) before ischemic stroke occurs is a priority for stroke prevention in AF. Smartphone camera-based photoplethysmographic (PPG) pulse waveform measurement discriminates between different heart rhythms, but its ability to diagnose AF in real-world situations has not been adequately investigated. We sought to assess the diagnostic performance of a standalone smartphone PPG application, Cardiio Rhythm, for AF screening in primary care setting. Patients with hypertension, with diabetes mellitus, and/or aged ≥65 years were recruited. A single-lead ECG was recorded by using the AliveCor heart monitor with tracings reviewed subsequently by 2 cardiologists to provide the reference standard. PPG measurements were performed by using the Cardiio Rhythm smartphone application. AF was diagnosed in 28 (2.76%) of 1013 participants. The diagnostic sensitivity of the Cardiio Rhythm for AF detection was 92.9% (95% CI] 77-99%) and was higher than that of the AliveCor automated algorithm (71.4% [95% CI 51-87%]). The specificities of Cardiio Rhythm and the AliveCor automated algorithm were comparable (97.7% [95% CI: 97-99%] versus 99.4% [95% CI 99-100%]). The positive predictive value of the Cardiio Rhythm was lower than that of the AliveCor automated algorithm (53.1% [95% CI 38-67%] versus 76.9% [95% CI 56-91%]); both had a very high negative predictive value (99.8% [95% CI 99-100%] versus 99.2% [95% CI 98-100%]). The Cardiio Rhythm smartphone PPG application provides an accurate and reliable means to detect AF in patients at risk of developing AF and has the potential to enable population-based screening for AF. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Does the STAF score help detect paroxysmal atrial fibrillation in acute stroke patients?

PubMed

Horstmann, S; Rizos, T; Güntner, J; Hug, A; Jenetzky, E; Krumsdorf, U; Veltkamp, R

2013-01-01

Detecting paroxysmal atrial fibrillation (pAF) soon after acute cerebral ischaemia has a major impact on secondary stroke prevention. Recently, the STAF score, a composite of clinical and instrumental findings, was introduced to identify stroke patients at risk of pAF. We aimed to validate this score in an independent study population. Consecutive patients admitted to our stroke unit with acute ischaemic stroke were prospectively enrolled. The diagnostic work-up included neuroimaging, neuroultrasound, baseline 12-channel electrocardiogram (ECG), 24-h Holter ECG, continuous ECG monitoring, and echocardiography. Presence of AF was documented according to the medical history of each patient and after review of 12-lead ECG, 24-h Holter ECG, or continuous ECG monitoring performed during the stay on the ward. Additionally, a telephone follow-up visit was conducted for each patient after 3 months to inquire about newly diagnosed AF. Items for each patient-age, baseline NIHSS, left atrial dilatation, and stroke etiology according to the TOAST criteria - were assessed to calculate the STAF score. Overall, 584 patients were enrolled in our analysis. AF was documented in 183 (31.3%) patients. In multivariable analysis, age, NIHSS, left atrial dilatation, and absence of vascular etiology were independent predictors for AF. The logistic AF-prediction model of the STAF score revealed fair classification accuracy in receiver operating characteristic curve analysis with an area under the curve of 0.84. STAF scores of ≥5 had a sensitivity of 79% and a specificity of 74% for predicting AF. The value of the STAF score for predicting the risk of pAF in stroke patients is limited. © 2012 The Author(s) European Journal of Neurology © 2012 EFNS.

XANTUS: rationale and design of a noninterventional study of rivaroxaban for the prevention of stroke in patients with atrial fibrillation

PubMed Central

Camm, A John; Amarenco, Pierre; Haas, Sylvia; Hess, Susanne; Kirchhof, Paulus; van Eickels, Martin; Turpie, Alexander GG

2014-01-01

Atrial fibrillation (AF) is associated with a fivefold increase in the risk of stroke. The Phase III ROCKET AF (Rivaroxaban Once-Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation) trial showed that rivaroxaban, an oral, direct Factor Xa inhibitor, was noninferior to warfarin for the reduction of stroke or systemic embolism in patients with AF. Compared with warfarin, rivaroxaban significantly reduced rates of intracranial and fatal hemorrhages, although not rates of bleeding overall. XANTUS (Xarelto® for Prevention of Stroke in Patients with Atrial Fibrillation) is a prospective, international, observational, postauthorization, noninterventional study designed to collect safety and efficacy data on the use of rivaroxaban for stroke prevention in AF in routine clinical practice. The key goal is to determine whether the safety profile of rivaroxaban established in ROCKET AF is also observed in routine clinical practice. XANTUS is designed as a single-arm cohort study to minimize selection bias, and will enroll approximately 6,000 patients (mostly from Europe) with nonvalvular AF prescribed rivaroxaban, irrespective of their level of stroke risk. Overall duration of follow-up will be 1 year; the first patient was enrolled in June 2012. Similar studies (XANTUS-EL [Xarelto® for Prevention of Stroke in Patients with Nonvalvular Atrial Fibrillation, Eastern Europe, Middle East, Africa and Latin America] and XANAP [Xarelto® for Prevention of Stroke in Patients with Atrial Fibrillation in Asia-Pacific]) are ongoing in Latin America and Asia-Pacific. Data from these studies will supplement those from ROCKET AF and provide practical information concerning the use of rivaroxaban for stroke prevention in AF. PMID:25083135

Spatial Resolution Requirements for Accurate Identification of Drivers of Atrial Fibrillation

PubMed Central

Roney, Caroline H.; Cantwell, Chris D.; Bayer, Jason D.; Qureshi, Norman A.; Lim, Phang Boon; Tweedy, Jennifer H.; Kanagaratnam, Prapa; Vigmond, Edward J.; Ng, Fu Siong

2017-01-01

Background— Recent studies have demonstrated conflicting mechanisms underlying atrial fibrillation (AF), with the spatial resolution of data often cited as a potential reason for the disagreement. The purpose of this study was to investigate whether the variation in spatial resolution of mapping may lead to misinterpretation of the underlying mechanism in persistent AF. Methods and Results— Simulations of rotors and focal sources were performed to estimate the minimum number of recording points required to correctly identify the underlying AF mechanism. The effects of different data types (action potentials and unipolar or bipolar electrograms) and rotor stability on resolution requirements were investigated. We also determined the ability of clinically used endocardial catheters to identify AF mechanisms using clinically recorded and simulated data. The spatial resolution required for correct identification of rotors and focal sources is a linear function of spatial wavelength (the distance between wavefronts) of the arrhythmia. Rotor localization errors are larger for electrogram data than for action potential data. Stationary rotors are more reliably identified compared with meandering trajectories, for any given spatial resolution. All clinical high-resolution multipolar catheters are of sufficient resolution to accurately detect and track rotors when placed over the rotor core although the low-resolution basket catheter is prone to false detections and may incorrectly identify rotors that are not present. Conclusions— The spatial resolution of AF data can significantly affect the interpretation of the underlying AF mechanism. Therefore, the interpretation of human AF data must be taken in the context of the spatial resolution of the recordings. PMID:28500175

Atrial fibrillation in patients with gastroesophageal reflux disease: a comprehensive review.

PubMed

Roman, Crina; Bruley des Varannes, Stanislas; Muresan, Lucian; Picos, Alina; Dumitrascu, Dan L

2014-07-28

To analyze the potential relationship between gastroesophageal reflux disease (GERD) and the development of atrial fibrillation (AF). Using the key words "atrial fibrillation and gastroesophageal reflux", "atrial fibrillation and esophagitis, peptic", "atrial fibrillation and hernia, hiatal" the PubMed, EMBASE, Cochrane Library, OVIDSP, WILEY databases were screened for relevant publications on GERD and AF in adults between January 1972-December 2013. Studies written in languages other than English or French, studies not performed in humans, reviews, case reports, abstracts, conference presentations, letters to the editor, editorials, comments and opinions were not taken into consideration. Articles treating the subject of radiofrequency ablation of AF and the consecutive development of GERD were also excluded. Two thousand one hundred sixty-one titles were found of which 8 articles met the inclusion criteria. The presence of AF in patients with GERD was reported to be between 0.62%-14%, higher compared to those without GERD. Epidemiological data provided by these observational studies showed that patients with GERD, especially those with more severe GERD-related symptoms, had an increased risk of developing AF compared with those without GERD, but a causal relationship between GERD and AF could not be established based on these studies. The mechanisms of AF as a consequence of GERD remain largely unknown, with inflammation and vagal stimulation playing a possible role in the development of these disorders. Treatment with proton pomp inhibitors may improve symptoms related to AF and facilitate conversion to sinus rhythm. Although links between AF and GERD exist, large randomized clinical studies are required for a better understanding of the relationship between these two entities.

Stroke with intermittent atrial fibrillation: incidence and predictors during aspirin therapy. Stroke Prevention in Atrial Fibrillation Investigators.

PubMed

Hart, R G; Pearce, L A; Rothbart, R M; McAnulty, J H; Asinger, R W; Halperin, J L

2000-01-01

This study was performed to characterize the risk of stroke in elderly patients with recurrent intermittent atrial fibrillation (AF). Although intermittent AF is common, relatively little is known about the attendant risk of stroke. A longitudinal cohort study was performed comparing 460 participants with intermittent AF with 1,552 with sustained AF treated with aspirin in the Stroke Prevention in Atrial Fibrillation studies and followed for a mean of two years. Independent risk factors for ischemic stroke were identified by multivariate analysis. Patients with intermittent AF were, on average, younger (66 vs. 70 years, p < 0.001), were more often women (37% vs. 26% p < 0.001) and less often had heart failure (11% vs. 21%, p < 0.001) than those with sustained AF. The annualized rate of ischemic stroke was similar for those with intermittent (3.2%) and sustained AF (3.3%). In patients with intermittent AF, independent predictors of ischemic stroke were advancing age (relative risk [RR] = 2.1 per decade, p < 0.001), hypertension (RR = 3.4, p = 0.003) and prior stroke (RR = 4.1, p = 0.01). Of those with intermittent AF predicted to be high risk (24%), the observed stroke rate was 7.8% per year (95% confidence interval 4.5 to 14). In this large cohort of AF patients given aspirin, those with intermittent AF had stroke rates similar to patients with sustained AF and similar stroke risk factors. Many elderly patients with recurrent intermittent AF have substantial rates of stroke and likely benefit from anticoagulation. High-risk patients with intermittent AF can be identified using the same clinical criteria that apply to patients with sustained AF.

Clinical predictors of risk for atrial fibrillation: implications for diagnosis and monitoring.

PubMed

Brunner, Kyle J; Bunch, T Jared; Mullin, Christopher M; May, Heidi T; Bair, Tami L; Elliot, David W; Anderson, Jeffrey L; Mahapatra, Srijoy

2014-11-01

To create a risk score using clinical factors to determine whom to screen and monitor for atrial fibrillation (AF). The AF risk score was developed based on the summed odds ratios (ORs) for AF development of 7 accepted clinical risk factors. The AF risk score is intended to assess the risk of AF similar to how the CHA2DS2-VASc score assesses stroke risk. Seven validated risk factors for AF were used to develop the AF risk score: age, coronary artery disease, diabetes mellitus, sex, heart failure, hypertension, and valvular disease. The AF risk score was tested within a random population sample of the Intermountain Healthcare outpatient database. Outcomes were stratified by AF risk score for OR and Kaplan-Meier analysis. A total of 100,000 patient records with an index follow-up from January 1, 2002, through December 31, 2007, were selected and followed up for the development of AF through the time of this analysis, May 13, 2013, through September 6, 2013. Mean ± SD follow-up time was 3106±819 days. The ORs of subsequent AF diagnosis of patients with AF risk scores of 1, 2, 3, 4, and 5 or higher were 3.05, 12.9, 22.8, 34.0, and 48.0, respectively. The area under the curve statistic for the AF risk score was 0.812 (95% CI, 0.805-0.820). We developed a simple AF risk score made up of common clinical factors that may be useful to possibly select patients for long-term monitoring for AF detection. Copyright © 2014 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

Rationale and design of a prospective study of the clinical significance of atrial arrhythmias detected by implanted device diagnostics: the TRENDS study.

PubMed

Glotzer, Taya V; Daoud, Emile G; Wyse, D George; Singer, Daniel E; Holbrook, Reece; Pruett, Khadeeja; Smith, Kenneth; Hilker, Christopher E

2006-01-01

Sustained atrial fibrillation (AF) is a common risk factor for stroke. While intermittent AF also appears to pose a substantial stroke risk, the quantitative relationship between the percentage of time spent in AF and stroke risk is poorly specified and "intermittent" AF is not the same as paroxysmal AF. Improved assessment of the impact of AF burden on stroke risk will allow more targeted and safer use of antithrombotic therapy. The primary objective of this study is to determine if AT/AF (all device detected atrial tachyarrhythmias, including atrial flutter, atrial fibrillation, and atrial tachycardia) burden over a 30 day period is an independent predictor of the occurrence of ischemic stroke, transient ischemic attack (TIA) and/or systemic embolism in subjects not receiving anticoagulation therapy. TRENDS is a prospective, post-market, non-randomized, multicenter study designed to enroll 3100 subjects who have an independent Class I/II indication for cardiac rhythm device implantation and who have demographic features suggestive of an increased risk for thromboembolic complications related to AT/AF. All implanted devices will have the ability to collect long-term AT/AF burden trending data and will be equivalently programmed to ensure consistent data collection. All subjects will be followed with device interrogations every 3 months and clinic visits every 6 months for 1 year. Subjects with a documented history of AT/AF prior to enrollment and those who develop AT/AF during the 12-month follow-up will be followed until the last subject enrolled in the study has completed their 24-month follow-up. The results of the TRENDS study should help clarify the implications of data retrieved from an implantable device with regard to the risk for thromboembolic complications from atrial arrhythmias, even in the absence of symptoms.

Atrial Fibrillation: The Science behind Its Defiance

PubMed Central

Czick, Maureen E.; Shapter, Christine L.; Silverman, David I.

2016-01-01

Atrial fibrillation (AF) is the most prevalent arrhythmia in the world, due both to its tenacious treatment resistance, and to the tremendous number of risk factors that set the stage for the atria to fibrillate. Cardiopulmonary, behavioral, and psychological risk factors generate electrical and structural alterations of the atria that promote reentry and wavebreak. These culminate in fibrillation once atrial ectopic beats set the arrhythmia process in motion. There is growing evidence that chronic stress can physically alter the emotion centers of the limbic system, changing their input to the hypothalamic-limbic-autonomic network that regulates autonomic outflow. This leads to imbalance of the parasympathetic and sympathetic nervous systems, most often in favor of sympathetic overactivation. Autonomic imbalance acts as a driving force behind the atrial ectopy and reentry that promote AF. Careful study of AF pathophysiology can illuminate the means that enable AF to elude both pharmacological control and surgical cure, by revealing ways in which antiarrhythmic drugs and surgical and ablation procedures may paradoxically promote fibrillation. Understanding AF pathophysiology can also help clarify the mechanisms by which emerging modalities aiming to correct autonomic imbalance, such as renal sympathetic denervation, may offer potential to better control this arrhythmia. Finally, growing evidence supports lifestyle modification approaches as adjuncts to improve AF control. PMID:27699086

Cost considerations in the management of atrial fibrillation – impact of dronedarone

PubMed Central

Khaykin, Yaariv; Shamiss, Yana

2012-01-01

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. It is associated with significant morbidity and mortality. At the societal level, AF carries an enormous cost. Strategies aimed at reducing AF morbidity and mortality and containing the associated fiscal burden are of paramount importance. This review will discuss AF treatment strategies and economics, focusing on the impact of dronedarone, a novel antiarrhythmic agent. PMID:22427725

Atrial Fibrillation Genetic Risk and Ischemic Stroke Mechanisms.

PubMed

Lubitz, Steven A; Parsons, Owen E; Anderson, Christopher D; Benjamin, Emelia J; Malik, Rainer; Weng, Lu-Chen; Dichgans, Martin; Sudlow, Cathie L; Rothwell, Peter M; Rosand, Jonathan; Ellinor, Patrick T; Markus, Hugh S; Traylor, Matthew

2017-06-01

Atrial fibrillation (AF) is a leading cause of cardioembolic stroke, but the relationship between AF and noncardioembolic stroke subtypes are unclear. Because AF may be unrecognized, and because AF has a substantial genetic basis, we assessed for predisposition to AF across ischemic stroke subtypes. We examined associations between AF genetic risk and Trial of Org 10172 in Acute Stroke Treatment stroke subtypes in 2374 ambulatory individuals with ischemic stroke and 5175 without from the Wellcome Trust Case-Control Consortium 2 using logistic regression. We calculated AF genetic risk scores using single-nucleotide polymorphisms associated with AF in a previous independent analysis across a range of preselected significance thresholds. There were 460 (19.4%) individuals with cardioembolic stroke, 498 (21.0%) with large vessel, 474 (20.0%) with small vessel, and 814 (32.3%) individuals with strokes of undetermined cause. Most AF genetic risk scores were associated with stroke, with the strongest association ( P =6×10 - 4 ) attributed to scores of 944 single-nucleotide polymorphisms (each associated with AF at P <1×10 - 3 in a previous analysis). Associations between AF genetic risk and stroke were enriched in the cardioembolic stroke subset (strongest P =1.2×10 - 9 , 944 single-nucleotide polymorphism score). In contrast, AF genetic risk was not significantly associated with noncardioembolic stroke subtypes. Comprehensive AF genetic risk scores were specific for cardioembolic stroke. Incomplete workups and subtype misclassification may have limited the power to detect associations with strokes of undetermined pathogenesis. Future studies are warranted to determine whether AF genetic risk is a useful biomarker to enhance clinical discrimination of stroke pathogeneses. © 2017 American Heart Association, Inc.

Impact of catheter ablation with remote magnetic navigation on procedural outcomes in patients with persistent and long-standing persistent atrial fibrillation.

PubMed

Jin, Qi; Pehrson, Steen; Jacobsen, Peter Karl; Chen, Xu

2015-11-01

The objectives of this study were to assess the procedural outcomes of persistent and long-standing persistent atrial fibrillation (PsAF and L-PsAF) ablation guided by remote magnetic navigation (RMN), and to detect factors predicting acute restoration of sinus rhythm (SR) by ablation with RMN. A total of 313 patients (275 male, age 59 ± 9.5 years) with PsAF (187/313) or L-PsAF (126/313) undergoing ablation using RMN were included. Patients' disease history, pulmonary venous anatomy, left atrial (LA) volume, procedure time, mapping plus ablation time, radiofrequency (RF) ablation time, fluoroscopy time, radiation dose, and complications were assessed. Stepwise regression was used to predict which variable could best predict acute restoration from AF to SR by ablation. Compared to PsAF, procedure time and RF ablation time were significantly increased in patients with L-PsAF (P = 0.01 and P < 0.001, respectively). No major complications occurred during the procedures in either PsAF or L-PsAF patients. Fifty five of 313 patients converted directly to SR by ablation. Compared to L-PsAF, the rate of SR restoration was significantly higher in PsAF (21 vs 12%, P = 0.03). Stepwise regression analysis showed LA volume was the primary parameter affecting SR restoration (P = 0.01). The LA volume of patients without direct SR restoration by ablation was 24% greater than that of patients with SR restoration (P < 0.001). Catheter ablation using RMN is a safe and effective method for PsAF and L-PsAF. LA volume could be a predictor of direct restoration of SR from sustaining AF by ablation using RMN.

Left atrial ejection force predicts the outcome after catheter ablation for paroxysmal atrial fibrillation.

PubMed

Kishima, Hideyuki; Mine, Takanao; Takahashi, Satoshi; Ashida, Kenki; Ishihara, Masaharu; Masuyama, Tohru

2018-02-01

Left atrium (LA) systolic dysfunction is observed in the early stages of atrial fibrillation (AF) prior to LA anatomical change. We investigated whether LA systolic dysfunction predicts recurrent AF after catheter ablation (CA) in patients with paroxysmal AF. We studied 106 patients who underwent CA for paroxysmal AF. LA systolic function was assessed with the LA emptying volume = Maximum LA volume (LAV max ) - Minimum LA volume (LAV min ), LA emptying fraction = [(LAV max - LAV min )/LAV max ] × 100, and LA ejection force calculated with Manning's method [LA ejection force = (0.5 × ρ × mitral valve area × A 2 )], where ρ is the blood density and A is the late-diastolic mitral inflow velocity. Recurrent AF was detected in 35/106 (33%) during 14.6 ± 9.1 months. Univariate analysis revealed reduced LA ejection force, decreased LA emptying fraction, larger LA diameter, and elevated brain natriuretic peptide as significant variables. On multivariate analysis, reduced LA ejection force and larger LA diameter were independently associated with recurrent AF. Moreover, patients with reduced LA ejection force and larger LA diameter had a higher risk of recurrent AF than preserved LA ejection force (log-rank P = 0.0004). Reduced LA ejection force and larger LA diameter were associated with poor outcome after CA for paroxysmal AF, and could be a new index to predict recurrent AF. © 2017 Wiley Periodicals, Inc.

Estimating the Prevalence of Atrial Fibrillation from A Three-Class Mixture Model for Repeated Diagnoses

PubMed Central

Li, Liang; Mao, Huzhang; Ishwaran, Hemant; Rajeswaran, Jeevanantham; Ehrlinger, John; Blackstone, Eugene H.

2016-01-01

Atrial fibrillation (AF) is an abnormal heart rhythm characterized by rapid and irregular heart beat, with or without perceivable symptoms. In clinical practice, the electrocardiogram (ECG) is often used for diagnosis of AF. Since the AF often arrives as recurrent episodes of varying frequency and duration and only the episodes that occur at the time of ECG can be detected, the AF is often underdiagnosed when a limited number of repeated ECGs are used. In studies evaluating the efficacy of AF ablation surgery, each patient undergo multiple ECGs and the AF status at the time of ECG is recorded. The objective of this paper is to estimate the marginal proportions of patients with or without AF in a population, which are important measures of the efficacy of the treatment. The underdiagnosis problem is addressed by a three-class mixture regression model in which a patient’s probability of having no AF, paroxysmal AF, and permanent AF is modeled by auxiliary baseline covariates in a nested logistic regression. A binomial regression model is specified conditional on a subject being in the paroxysmal AF group. The model parameters are estimated by the EM algorithm. These parameters are themselves nuisance parameters for the purpose of this research, but the estimators of the marginal proportions of interest can be expressed as functions of the data and these nuisance parameters and their variances can be estimated by the sandwich method. We examine the performance of the proposed methodology in simulations and two real data applications. PMID:27983754

Antithrombotic treatment for stroke prevention in atrial fibrillation: The Asian agenda.

PubMed

Chen, Chen-Huan; Chen, Mien-Cheng; Gibbs, Harry; Kwon, Sun U; Lo, Sidney; On, Young Keun; Rosman, Azhari; Suwanwela, Nijasri C; Tan, Ru San; Tirador, Louie S; Zirlik, Andreas

2015-07-15

Atrial fibrillation (AF) is the most common heart arrhythmia. Untreated AF incurs a considerable burden of stroke and associated healthcare costs. Asians have AF risk factors similar to Caucasians and a similarly increased risk of AF-related stroke; however, with a vast and rapidly ageing population, Asia bears a disproportionately large disease burden. Urgent action is warranted to avert this potential health crisis. Antithrombotic therapy with oral anticoagulants is the most effective means of preventing stroke in AF and is a particular priority in Asia given the increasing disease burden. However, AF in Asia remains undertreated. Conventional oral anticoagulation with warfarin is problematic in Asia due to suboptimal control and a propensity among Asians to warfarin-induced intracranial haemorrhage. Partly due to concerns about intracranial haemorrhage, there are considerable gaps between AF treatment guidelines and clinical practice in Asia, in particular overuse of antiplatelet agents and underuse of anticoagulants. Compared with warfarin, new direct thrombin inhibitors and Factor Xa inhibitors are non-inferior in preventing stroke and significantly reduce the risk of life-threatening bleeding, particularly intracranial bleeding. These agents may therefore provide an appropriate alternative to warfarin in Asian patients. There is considerable scope to improve stroke prevention in AF in Asia. Key priorities include: early detection of AF and identification of asymptomatic patients; assessment of stroke and bleeding risk for all AF patients; evidence-based pharmacotherapy with direct-acting oral anticoagulant agents or vitamin K antagonists for AF patients at risk of stroke; controlling hypertension; and awareness-raising, education and outreach among both physicians and patients. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Estimating the prevalence of atrial fibrillation from a three-class mixture model for repeated diagnoses.

PubMed

Li, Liang; Mao, Huzhang; Ishwaran, Hemant; Rajeswaran, Jeevanantham; Ehrlinger, John; Blackstone, Eugene H

2017-03-01

Atrial fibrillation (AF) is an abnormal heart rhythm characterized by rapid and irregular heartbeat, with or without perceivable symptoms. In clinical practice, the electrocardiogram (ECG) is often used for diagnosis of AF. Since the AF often arrives as recurrent episodes of varying frequency and duration and only the episodes that occur at the time of ECG can be detected, the AF is often underdiagnosed when a limited number of repeated ECGs are used. In studies evaluating the efficacy of AF ablation surgery, each patient undergoes multiple ECGs and the AF status at the time of ECG is recorded. The objective of this paper is to estimate the marginal proportions of patients with or without AF in a population, which are important measures of the efficacy of the treatment. The underdiagnosis problem is addressed by a three-class mixture regression model in which a patient's probability of having no AF, paroxysmal AF, and permanent AF is modeled by auxiliary baseline covariates in a nested logistic regression. A binomial regression model is specified conditional on a subject being in the paroxysmal AF group. The model parameters are estimated by the Expectation-Maximization (EM) algorithm. These parameters are themselves nuisance parameters for the purpose of this research, but the estimators of the marginal proportions of interest can be expressed as functions of the data and these nuisance parameters and their variances can be estimated by the sandwich method. We examine the performance of the proposed methodology in simulations and two real data applications. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Atrial fibrillation in patients with gastroesophageal reflux disease: A comprehensive review

PubMed Central

Roman, Crina; Bruley des Varannes, Stanislas; Muresan, Lucian; Picos, Alina; Dumitrascu, Dan L

2014-01-01

AIM: To analyze the potential relationship between gastroesophageal reflux disease (GERD) and the development of atrial fibrillation (AF). METHODS: Using the key words “atrial fibrillation and gastroesophageal reflux”, “atrial fibrillation and esophagitis, peptic”, “atrial fibrillation and hernia, hiatal” the PubMed, EMBASE, Cochrane Library, OVIDSP, WILEY databases were screened for relevant publications on GERD and AF in adults between January 1972-December 2013. Studies written in languages other than English or French, studies not performed in humans, reviews, case reports, abstracts, conference presentations, letters to the editor, editorials, comments and opinions were not taken into consideration. Articles treating the subject of radiofrequency ablation of AF and the consecutive development of GERD were also excluded. RESULTS: Two thousand one hundred sixty-one titles were found of which 8 articles met the inclusion criteria. The presence of AF in patients with GERD was reported to be between 0.62%-14%, higher compared to those without GERD. Epidemiological data provided by these observational studies showed that patients with GERD, especially those with more severe GERD-related symptoms, had an increased risk of developing AF compared with those without GERD, but a causal relationship between GERD and AF could not be established based on these studies. The mechanisms of AF as a consequence of GERD remain largely unknown, with inflammation and vagal stimulation playing a possible role in the development of these disorders. Treatment with proton pomp inhibitors may improve symptoms related to AF and facilitate conversion to sinus rhythm. CONCLUSION: Although links between AF and GERD exist, large randomized clinical studies are required for a better understanding of the relationship between these two entities. PMID:25071357

Direct Proof of Endo-Epicardial Asynchrony of the Atrial Wall During Atrial Fibrillation in Humans.

PubMed

de Groot, Natasja; van der Does, Lisette; Yaksh, Ameeta; Lanters, Eva; Teuwen, Christophe; Knops, Paul; van de Woestijne, Pieter; Bekkers, Jos; Kik, Charles; Bogers, Ad; Allessie, Maurits

2016-05-01

The presence of focal fibrillation waves during atrial fibrillation (AF) can, besides ectopic activity, also be explained by asynchronous activation of the atrial endo- and epicardial layer and transmurally propagating fibrillation waves. To provide direct proof of endo-epicardial asynchrony, we performed simultaneous high-resolution mapping of the right atrial endo- and epicardial wall during AF in humans. Intraoperative mapping of the endo- and epicardial right atrial wall was performed during (induced) AF in 10 patients with AF (paroxysmal: n=3; persistent: n=4; and longstanding persistent: n=3) and 4 patients without a history of AF. A clamp made of 2 rectangular 8×16 electrode arrays (interelectrode distance 2 mm) was inserted into the incision in the right atrial appendage. Recordings of 10 seconds of AF were analyzed to determine the incidence of asynchronous endo-epicardial activation times (≥15 ms) of opposite electrodes. Asynchronous endo-epicardial activation ranged between 0.9 and 55.9% without preference for either side. Focal waves appeared equally frequent at endocardium and epicardium (11% versus 13%; ITALIC! P=0.18). Using strict criteria for breakthrough (presence of an opposite wave within 4 mm and ≤14 ms before the origin of the focal wave), the majority (65%) of all focal fibrillation waves could be attributed to endo-epicardial excitation. We provided the first evidence for asynchronous activation of the endo-epicardial wall during AF in humans. Endo-epicardial asynchrony may play a major role in the pathophysiology of AF and may offer an explanation why in some patients therapy fails. © 2016 American Heart Association, Inc.

Diagnostic performance of an automatic blood pressure measurement device, Microlife WatchBP Home A, for atrial fibrillation screening in a real-world primary care setting.

PubMed

Chan, Pak-Hei; Wong, Chun-Ka; Pun, Louise; Wong, Yu-Fai; Wong, Michelle Man-Ying; Chu, Daniel Wai-Sing; Siu, Chung-Wah

2017-06-15

To evaluate the diagnostic performance of a UK National Institute for Health and Care Excellence-recommended automatic oscillometric blood pressure (BP) measurement device incorporated with an atrial fibrillation (AF) detection algorithm (Microlife WatchBP Home A) for real-world AF screening in a primary healthcare setting. Primary healthcare setting in Hong Kong. This was a prospective AF screening study carried out between 1 September 2014 and 14 January 2015. The Microlife device was evaluated for AF detection and compared with a reference standard of lead-I ECG. Diagnostic performance of Microlife for AF detection. 5969 patients (mean age: 67.2±11.0 years; 53.9% female) were recruited. The mean CHA 2 DS 2 -VASc ( C : congestive heart failure [1 point]; H : hypertension [1 point]; A 2 : age 65-74 years [1 point] and age ≥75 years [2 points]; D : diabetes mellitus [1 point]; S : prior stroke or transient ischemic attack [2 points]; VA : vascular disease [1 point]; and Sc : sex category [female] [1 point])score was 2.8±1.3. AF was diagnosed in 72 patients (1.21%) and confirmed by a 12-lead ECG. The Microlife device correctly identified AF in 58 patients and produced 79 false-positives. The corresponding sensitivity and specificity for AF detection were 80.6% (95% CI 69.5 to 88.9) and 98.7% (95% CI 98.3 to 98.9), respectively. Among patients with a false-positive by the Microlife device, 30.4% had sinus rhythm, 35.4% had sinus arrhythmia and 29.1% exhibited premature atrial complexes. With the low prevalence of AF in this population, the positive and negative predictive values of Microlife device for AF detection were 42.4% (95% CI 34.0 to 51.2) and 99.8% (95% CI 99.6 to 99.9), respectively. The overall diagnostic performance of Microlife device to detect AF as determined by area under the curves was 0.90 (95% CI 0.89 to 0.90). In the primary care setting, Microlife WatchBP Home was an effective means to screen for AF, with a reasonable sensitivity of 80.6% and a high negative predictive value of 99.8%, in addition to its routine function of BP measurement. In a younger patient population aged <65 years with a lower prevalence of AF, Microlife WatchBP Home A demonstrated a similar diagnostic accuracy. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Incidence and prognostic significance of new onset atrial fibrillation/flutter in acute pericarditis.

PubMed

Imazio, Massimo; Lazaros, George; Picardi, Elisa; Vasileiou, Panagiotis; Orlando, Fabrizio; Carraro, Mara; Tsiachris, Dimitris; Vlachopoulos, Charalambos; Georgiopoulos, George; Tousoulis, Dimitrios; Belli, Riccardo; Gaita, Fiorenzo

2015-09-01

Data on the incidence of new onset atrial fibrillation and flutter (AF/f) in patients with acute pericarditis are limited. We sought to determine the incidence and prognostic significance of AF/f in this setting. Between January 2006 and June 2014, consecutive new cases of acute pericarditis were included in two urban referral centres for pericardial diseases. All new cases of AF/f defined as episodes lasting ≥30 s were recorded. Events considered during follow-up consisted of AF/f and pericarditis recurrence, cardiac tamponade, pericardial constriction and death. 822 consecutive new cases of acute pericarditis (mean age 53±15 years, 444 men) were analysed. AF/f was detected in 35 patients (4.3%, mean age 66.5±11.3 years, 18 men). Patients with AF/f were significantly older (p=0.017) and presented more frequently with pericardial effusion (p<0.001). Arrhythmias developed within 24 h of pericarditis onset in 91.4% of cases, lasted >24 h in 25.7% and spontaneously converted in 74.3% of patients. Underlying structural heart disease was present in 17% of AF/f cases. In a 30-month follow-up, patients with history of AF/f at the initial episode had a higher rate of arrhythmia occurrence (34.3% vs 0.9%, p<0.001), mostly (75%) within 3 months. No other differences were detected in additional clinical events including haemorrhagic complications in patients receiving oral anticoagulation. The occurrence of AF/f in acute pericarditis identifies a predisposed population to AF/f with a high recurrence risk (about 35%): in these patients, pericarditis may act as an arrhythmic trigger and oral anticoagulation should be seriously considered according to guidelines. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Study protocol for Smartphone Monitoring for Atrial fibrillation in Real-Time in India (SMART-India): a community-based screening and referral programme.

PubMed

Soni, Apurv; Karna, Sunil; Patel, Harshil; Fahey, Nisha; Raithatha, Shyamsundar; Handorf, Anna; Bostrom, John; Bashar, Syed; Talati, Kandarp; Shah, Ravi; Goldberg, Robert J; Thanvi, Sunil; Phatak, Ajay Gajanan; Allison, Jeroan J; Chon, Ki; Nimbalkar, Somashekhar Marutirao; McManus, David D

2017-12-14

Atrial fibrillation (AF), the world's most common arrhythmia, often goes undetected and untreated in low-resource communities, including India, where AF epidemiology is undefined. AF is an important risk factor for stroke, which plagues an estimated 1.6 million Indians annually. As such, early detection of AF and management of high-risk patients is critically important to decrease stroke burden in individuals with AF. This study aims to describe the epidemiology of AF in Anand District, Gujarat, India, characterise the clinical profile of individuals who are diagnosed with AF and determine the performance of two mobile technologies for community-based AF screening. This observational study builds on findings from a previous feasibility study and leverages two novel technologies as well as an existing community health programme to perform door-to-door AF screening for 2000 people from 60 villages of Anand District, Gujarat, India using local health workers. A single-lead ECG and a pulse-based application is used to screen each individual for AF three times over a period of 5 days. Participants with suspected arrhythmias are followed up by study cardiologist who makes final diagnoses. Participants diagnosed with AF are initiated on treatment based on current anticoagulation guidelines and clinical reasoning. Age-stratified and sex-stratified prevalence of AF in the Anand District will be calculated for sample and estimated for Anand distribution using survey design weights. Sociodemographic and clinical factors associated with AF will be evaluated using multivariable regression methods. Performance of each mobile technology in detecting AF will be evaluated using a 12-lead ECG interpretation as the gold standard. This protocol was approved separately by the Institutional Review Board of University of Massachusetts Medical School and the Human Research Ethics Committee at Charutar Arogya Mandal. The findings of this study will be disseminated through peer-reviewed journals and scientific conferences. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Predisposing factors for atrial fibrillation in the elderly

PubMed Central

Wasmer, Kristina; Eckardt, Lars; Breithardt, Günter

2017-01-01

Atrial fibrillation (AF) in the elderly occurs as a consequence of cardiovascular aging and an age related increase of comorbidity. Several predisposing factors for AF have been identified for the overall AF population. Most of them, cardiovascular disease in particular, play a role in younger and older patients. The longer time period during which these risk factors can cause structural changes that ultimately lead to AF may, at least in part, explain the association between age and AF. In addition, less well defined age-related changes in cellular electrophysiologic properties and structure predispose to AF in the elderly. PMID:28592961

A review of apixaban for stroke prevention in atrial fibrillation: insights from ARISTOTLE.

PubMed

Hess, Connie N; Al-Khatib, Sana M; Granger, Christopher B; Lopes, Renato

2013-09-01

Atrial fibrillation (AF) is associated with significant mortality and morbidity, and stroke represents the most-feared complication. Consequently, AF treatment has focused on thromboprophylaxis, with warfarin as the mainstay of therapy. However, concerns over ease of use and safety have limited its use. Three novel oral anticoagulants have been approved for use in stroke prevention in AF based on randomized data: 1) dabigatran, studied in Randomized Evaluation of Long-term Anticoagulation Therapy (RE-LY); 2) rivaroxaban, studied in Rivaroxaban Once-daily, Oral, Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF); and 3) apixaban, studied in Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE). In this review, we focus on apixaban and discuss subgroup analyses that have been performed in the three trials comparing novel oral anticoagulants with warfarin. We conclude with recommendations regarding further investigations.

Persistent atrial fibrillation vs paroxysmal atrial fibrillation: differences in management.

PubMed

Margulescu, Andrei D; Mont, Lluis

2017-08-01

Atrial fibrillation (AF) is the most common human arrhythmia. AF is a progressive disease, initially being nonsustained and induced by trigger activity, and progressing towards persistent AF through alteration of the atrial myocardial substrate. Treatment of AF aims to decrease the risk of stroke and improve the quality of life, by preventing recurrences (rhythm control) or controlling the heart rate during AF (rate control). In the last 20 years, catheter-based and, less frequently, surgical and hybrid ablation techniques have proven more successful compared with drug therapy in achieving rhythm control in patients with AF. However, the efficiency of ablation techniques varies greatly, being highest in paroxysmal and lowest in long-term persistent AF. Areas covered: In this review, we discuss the fundamental differences between paroxysmal and persistent AF and the potential impact of those differences on patient management, emphasizing the available therapeutic strategies to achieve rhythm control. Expert commentary: Treatment to prevent AF recurrences is suboptimal, particularly in patients with persistent AF. Emerging technologies, such as documentation of atrial fibrosis using magnetic resonance imaging and documentation of electrical substrate using advanced electrocardiographic imaging techniques are likely to provide valuable insights about patient-specific tailoring of treatments.

Does periprocedural anticoagulation management of atrial fibrillation affect the prevalence of silent thromboembolic lesion detected by diffusion cerebral magnetic resonance imaging in patients undergoing radiofrequency atrial fibrillation ablation with open irrigated catheters? Results from a prospective multicenter study.

PubMed

Di Biase, Luigi; Gaita, Fiorenzo; Toso, Elisabetta; Santangeli, Pasquale; Mohanty, Prasant; Rutledge, Neal; Yan, Xue; Mohanty, Sanghamitra; Trivedi, Chintan; Bai, Rong; Price, Justin; Horton, Rodney; Gallinghouse, G Joseph; Beheiry, Salwa; Zagrodzky, Jason; Canby, Robert; Leclercq, Jean François; Halimi, Franck; Scaglione, Marco; Cesarani, Federico; Faletti, Riccardo; Sanchez, Javier; Burkhardt, J David; Natale, Andrea

2014-05-01

Silent cerebral ischemia (SCI) has been reported in 14% of cases after catheter ablation of atrial fibrillation (AF) with radiofrequency (RF) energy and discontinuation of warfarin before AF ablation procedures. The purpose of this study was to determine whether periprocedural anticoagulation management affects the incidence of SCI after RF ablation using an open irrigated catheter. Consecutive patients undergoing RF ablation for AF without warfarin discontinuation and receiving heparin bolus before transseptal catheterization (group I, n = 146) were compared with a group of patients who had protocol deviation in terms of maintaining the therapeutic preprocedural international normalized ratio (patients with subtherapeutic INR) and/or failure to receive pretransseptal heparin bolus infusion and/or ≥2 consecutive ACT measurements <300 seconds (noncompliant population, group II, n = 134) and with a group of patients undergoing RF ablation with warfarin discontinuation bridged with low molecular weight heparin (group III, n = 148). All patients underwent preablation and postablation (within 48 hours) diffusion magnetic resonance imaging. SCI was detected in 2% of patients (3/146) in group I, 7% (10/134) in group II, and 14% (21/148) in group III (P <.001). "Therapeutic INR" was strongly associated with a lower prevalence of postprocedural silent cerebral ischemia (SCI). Multivariable analysis demonstrated nonparoxysmal AF (odds ratio 3.8, 95% confidence interval 1.5-9.7, P = .005) and noncompliance to protocol (odds ratio 2.8, 95% confidence interval 1.5-5.1, P <.001] to be significant predictors of ischemic events. Strict adherence to an anticoagulation protocol significantly reduces the prevalence of SCI after catheter ablation of AF with RF energy. Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Prediction of new-onset atrial fibrillation after first-ever ischemic stroke: A comparison of CHADS2, CHA2DS2-VASc and HATCH scores and the added value of stroke severity.

PubMed

Hsieh, Cheng-Yang; Lee, Cheng-Han; Wu, Darren Philbert; Sung, Sheng-Feng

2018-05-01

Early detection of atrial fibrillation after stroke is important for secondary prevention in stroke patients without known atrial fibrillation (AF). We aimed to compare the performance of CHADS 2 , CHA 2 DS 2 -VASc and HATCH scores in predicting AF detected after stroke (AFDAS) and to test whether adding stroke severity to the risk scores improves predictive performance. Adult patients with first ischemic stroke event but without a prior history of AF were retrieved from a nationwide population-based database. We compared C-statistics of CHADS 2 , CHA 2 DS 2 -VASc and HATCH scores for predicting the occurrence of AFDAS during stroke admission (cohort I) and during follow-up after hospital discharge (cohort II). The added value of stroke severity to prediction models was evaluated using C-statistics, net reclassification improvement, and integrated discrimination improvement. Cohort I comprised 13,878 patients and cohort II comprised 12,567 patients. Among them, 806 (5.8%) and 657 (5.2%) were diagnosed with AF, respectively. The CHADS 2 score had the lowest C-statistics (0.558 in cohort I and 0.597 in cohort II), whereas the CHA 2 DS 2 -VASc score had comparable C-statistics (0.603 and 0.644) to the HATCH score (0.612 and 0.653) in predicting AFDAS. Adding stroke severity to each of the three risk scores significantly increased the model performance. In stroke patients without known AF, all three risk scores predicted AFDAS during admission and follow-up, but with suboptimal discrimination. Adding stroke severity improved their predictive abilities. These risk scores, when combined with stroke severity, may help prioritize patients for continuous cardiac monitoring in daily practice. Copyright © 2018 Elsevier B.V. All rights reserved.

Loss of atrial contractility is primary cause of atrial dilatation during first days of atrial fibrillation.

PubMed

Schotten, Ulrich; de Haan, Sunniva; Neuberger, Hans-Ruprecht; Eijsbouts, Sabine; Blaauw, Yuri; Tieleman, Robert; Allessie, Maurits

2004-11-01

Atrial fibrillation (AF) induces a progressive dilatation of the atria which in turn might promote the arrhythmia. The mechanism of atrial dilatation during AF is not known. To test the hypothesis that loss of atrial contractile function is a primary cause of atrial dilatation during the first days of AF, eight goats were chronically instrumented with epicardial electrodes, a pressure transducer in the right atrium, and piezoelectric crystals to measure right atrial diameter. AF was induced with the use of repetitive burst pacing. Atrial contractility was assessed during sinus rhythm, atrial pacing (160-, 300-, and 400-ms cycle length), and electrically induced AF. The compliance of the fibrillating right atrium was measured during unloading the atria with diuretics and loading with 1 liter of saline. All measurements were repeated after 6, 12, and 24 h of AF and then once a day during the first 5 days of AF. Recovery of the observed changes after spontaneous cardioversion was also studied. After 5 days of AF, atrial contractility during sinus rhythm or slow atrial pacing was greatly reduced. During rapid pacing (160 ms) or AF, the amplitude of the atrial pressure waves had declined to 20% of control. The compliance of the fibrillating atria increased twofold, whereas the right atrial pressure was unchanged. As a result, the mean right atrial diameter increased by approximately 12%. All changes were reversible within 3 days of sinus rhythm. We conclude that atrial dilatation during the first days of AF is due to an increase in atrial compliance caused by loss of atrial contractility during AF. Atrial compliance and size are restored when atrial contractility recovers after cardioversion of AF.

Increased Susceptibility to Atrial Fibrillation Secondary to Atrial Fibrosis in Transgenic Goats Expressing Transforming Growth Factor-β1

PubMed Central

Davies, Christopher J.; Regouski, Misha; Hall, Justin; Olsen, Aaron L.; Meng, Qinggang; Rutigliano, Heloisa M.; Dosdall, Derek J.; Angel, Nathan A.; Sachse, Frank B.; Seidel, Thomas; Thomas, Aaron J.; Stott, Rusty; Panter, Kip E.; Lee, Pamela M.; Van Wettere, Arnaud J.; Stevens, John R.; Wang, Zhongde; MacLeod, Rob S.; Marrouche, Nassir F.; White, Kenneth L.

2016-01-01

Introduction Large animal models of progressive atrial fibrosis would provide an attractive platform to study relationship between structural and electrical remodeling in atrial fibrillation (AF). Here we established a new transgenic goat model of AF with cardiac specific overexpression of TGF-β1 and investigated the changes in the cardiac structure and function leading to AF. Methods and Results Transgenic goats with cardiac specific overexpression of constitutively active TGF-β1 were generated by somatic cell nuclear transfer. We examined myocardial tissue, ECGs, echocardiographic data, and AF susceptibility in transgenic and wild-type control goats. Transgenic goats exhibited significant increase in fibrosis and myocyte diameters in the atria compared to controls, but not in the ventricles. P-wave duration was significantly greater in transgenic animals starting at 12-month of age, but no significant chamber enlargement was detected, suggesting conduction slowing in the atria. Furthermore, this transgenic goat model exhibited a significant increase in AF vulnerability. Six of 8 transgenic goats (75%) were susceptible to AF induction and exhibited sustained AF (>2 minutes), whereas, none of 6 controls displayed sustained AF (P<0.01). Length of induced AF episodes was also significantly greater in the transgenic group compared to controls (687±212.02 vs. 2.50±0.88 seconds, P<0.0001), but no persistent or permanent AF was observed. Conclusion A novel transgenic goat model with a substrate for AF was generated. In this model, cardiac overexpression of TGF-β1 led to an increase in fibrosis and myocyte size in the atria, and to progressive P-wave prolongation. We suggest that these factors underlie increased AF susceptibility. PMID:27447370

Increased Susceptibility to Atrial Fibrillation Secondary to Atrial Fibrosis in Transgenic Goats Expressing Transforming Growth Factor-β1.

PubMed

Polejaeva, Irina A; Ranjan, Ravi; Davies, Christopher J; Regouski, Misha; Hall, Justin; Olsen, Aaron L; Meng, Qinggang; Rutigliano, Heloisa M; Dosdall, Derek J; Angel, Nathan A; Sachse, Frank B; Seidel, Thomas; Thomas, Aaron J; Stott, Rusty; Panter, Kip E; Lee, Pamela M; Van Wettere, Arnaud J; Stevens, John R; Wang, Zhongde; MacLeod, Rob S; Marrouche, Nassir F; White, Kenneth L

2016-10-01

Large animal models of progressive atrial fibrosis would provide an attractive platform to study relationship between structural and electrical remodeling in atrial fibrillation (AF). Here we established a new transgenic goat model of AF with cardiac specific overexpression of TGF-β1 and investigated the changes in the cardiac structure and function leading to AF. Transgenic goats with cardiac specific overexpression of constitutively active TGF-β1 were generated by somatic cell nuclear transfer. We examined myocardial tissue, ECGs, echocardiographic data, and AF susceptibility in transgenic and wild-type control goats. Transgenic goats exhibited significant increase in fibrosis and myocyte diameters in the atria compared to controls, but not in the ventricles. P-wave duration was significantly greater in transgenic animals starting at 12 months of age, but no significant chamber enlargement was detected, suggesting conduction slowing in the atria. Furthermore, this transgenic goat model exhibited a significant increase in AF vulnerability. Six of 8 transgenic goats (75%) were susceptible to AF induction and exhibited sustained AF (>2 minutes), whereas none of 6 controls displayed sustained AF (P < 0.01). Length of induced AF episodes was also significantly greater in the transgenic group compared to controls (687 ± 212.02 seconds vs. 2.50 ± 0.88 seconds, P < 0.0001), but no persistent or permanent AF was observed. A novel transgenic goat model with a substrate for AF was generated. In this model, cardiac overexpression of TGF-β1 led to an increase in fibrosis and myocyte size in the atria, and to progressive P-wave prolongation. We suggest that these factors underlie increased AF susceptibility. © 2016 Wiley Periodicals, Inc.

Examining rare and low-frequency genetic variants previously associated with lone or familial forms of atrial fibrillation in an electronic medical record system: a cautionary note.

PubMed

Weeke, Peter; Denny, Joshua C; Basterache, Lisa; Shaffer, Christian; Bowton, Erica; Ingram, Christie; Darbar, Dawood; Roden, Dan M

2015-02-01

Studies in individuals or small kindreds have implicated rare variants in 25 different genes in lone and familial atrial fibrillation (AF) using linkage and segregation analysis, functional characterization, and rarity in public databases. Here, we used a cohort of 20 204 patients of European or African ancestry with electronic medical records and exome chip data to compare the frequency of AF among carriers and noncarriers of these rare variants. The exome chip included 19 of 115 rare variants, in 9 genes, previously associated with lone or familial AF. Using validated algorithms querying a combination of clinical notes, structured billing codes, ECG reports, and procedure codes, we identified 1056 AF cases (>18 years) and 19 148 non-AF controls (>50 years) with available genotype data on the Illumina HumanExome BeadChip v.1.0 in the Vanderbilt electronic medical record-linked DNA repository, BioVU. Known correlations between AF and common variants at 4q25 were replicated. None of the 19 variants previously associated with AF were over-represented among AF cases (P>0.1 for all), and the frequency of variant carriers among non-AF controls was >0.1% for 14 of 19. Repeat analyses using non-AF controls aged >60 (n=14 904), >70 (n=9670), and >80 (n=4729) years did not influence these findings. Rare variants previously implicated in lone or familial forms of AF present on the exome chip are detected at low frequencies in a general population but are not associated with AF. These findings emphasize the need for caution when ascribing variants as pathogenic or causative. © 2014 American Heart Association, Inc.

A review of rate control in atrial fibrillation, and the rationale and protocol for the RATE-AF trial

PubMed Central

Deeks, Jonathan J; Griffith, Michael; Lip, Gregory YH; Mehta, Samir; Slinn, Gemma; Stanbury, Mary; Steeds, Richard P; Townend, Jonathan N

2017-01-01

Background and objective Atrial fibrillation (AF) is common and causes impaired quality of life, an increased risk of stroke and death as well as frequent hospital admissions. The majority of patients with AF require control of heart rate. In this article, we summarise the limited evidence from clinical trials that guides prescription, and present the rationale and protocol for a new randomised trial. As rate control has not yet been shown to reduce mortality, there is a clear need to compare the impact of therapy on quality of life, cardiac function and exercise capacity. Such a trial should concentrate on the long-term effects of treatment in the largest proportion of patients with AF, those with symptomatic permanent AF, with the aim of improving patient well-being. Design and intervention The RAte control Therapy Evaluation in permanent Atrial Fibrillation (RATE-AF) trial will enrol 160 participants with a prospective, randomised, open-label, blinded end point design comparing initial rate control with digoxin or bisoprolol. This will be the first head-to-head randomised trial of digoxin and beta-blockers in AF. Participants Recruited patients will be aged ≥60 years with permanent AF and symptoms of breathlessness (equivalent to New York Heart Association class II or above), with few exclusion criteria to maximise generalisability to routine clinical practice. Outcome measures The primary outcome is patient-reported quality of life, with secondary outcomes including echocardiographic ventricular function, exercise capacity and biomarkers of cellular and clinical response. Follow-up will occur at 6 and 12 months, with feasibility components to inform the design of a future trial powered to detect a difference in hospital admission. The RATE-AF trial will underpin an integrated approach to management including biomarkers, functions and symptoms that will guide future research into optimal, personalised rate control in patients with AF. Ethics and dissemination East Midlands-Derby Research Ethics Committee (16/EM/0178); peer-reviewed publications. Trial registration Clinicaltrials.gov: NCT02391337; ISRCTN: 95259705. Pre-results. PMID:28729311

A review of rate control in atrial fibrillation, and the rationale and protocol for the RATE-AF trial.

PubMed

Kotecha, Dipak; Calvert, Melanie; Deeks, Jonathan J; Griffith, Michael; Kirchhof, Paulus; Lip, Gregory Yh; Mehta, Samir; Slinn, Gemma; Stanbury, Mary; Steeds, Richard P; Townend, Jonathan N

2017-07-20

Atrial fibrillation (AF) is common and causes impaired quality of life, an increased risk of stroke and death as well as frequent hospital admissions. The majority of patients with AF require control of heart rate. In this article , we summarise the limited evidence from clinical trials that guides prescription, and present the rationale and protocol for a new randomised trial. As rate control has not yet been shown to reduce mortality, there is a clear need to compare the impact of therapy on quality of life, cardiac function and exercise capacity. Such a trial should concentrate on the long-term effects of treatment in the largest proportion of patients with AF, those with symptomatic permanent AF, with the aim of improving patient well-being. The RAte control Therapy Evaluation in permanent Atrial Fibrillation (RATE-AF) trial will enrol 160 participants with a prospective, randomised, open-label, blinded end point design comparing initial rate control with digoxin or bisoprolol. This will be the first head-to-head randomised trial of digoxin and beta-blockers in AF. Recruited patients will be aged ≥60 years with permanent AF and symptoms of breathlessness (equivalent to New York Heart Association class II or above), with few exclusion criteria to maximise generalisability to routine clinical practice. The primary outcome is patient-reported quality of life, with secondary outcomes including echocardiographic ventricular function, exercise capacity and biomarkers of cellular and clinical response. Follow-up will occur at 6 and 12 months, with feasibility components to inform the design of a future trial powered to detect a difference in hospital admission. The RATE-AF trial will underpin an integrated approach to management including biomarkers, functions and symptoms that will guide future research into optimal, personalised rate control in patients with AF. East Midlands-Derby Research Ethics Committee (16/EM/0178); peer-reviewed publications. Clinicaltrials.gov: NCT02391337; ISRCTN: 95259705. Pre-results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Automatic detection of atrial fibrillation in cardiac vibration signals.

PubMed

Brueser, C; Diesel, J; Zink, M D H; Winter, S; Schauerte, P; Leonhardt, S

2013-01-01

We present a study on the feasibility of the automatic detection of atrial fibrillation (AF) from cardiac vibration signals (ballistocardiograms/BCGs) recorded by unobtrusive bedmounted sensors. The proposed system is intended as a screening and monitoring tool in home-healthcare applications and not as a replacement for ECG-based methods used in clinical environments. Based on BCG data recorded in a study with 10 AF patients, we evaluate and rank seven popular machine learning algorithms (naive Bayes, linear and quadratic discriminant analysis, support vector machines, random forests as well as bagged and boosted trees) for their performance in separating 30 s long BCG epochs into one of three classes: sinus rhythm, atrial fibrillation, and artifact. For each algorithm, feature subsets of a set of statistical time-frequency-domain and time-domain features were selected based on the mutual information between features and class labels as well as first- and second-order interactions among features. The classifiers were evaluated on a set of 856 epochs by means of 10-fold cross-validation. The best algorithm (random forests) achieved a Matthews correlation coefficient, mean sensitivity, and mean specificity of 0.921, 0.938, and 0.982, respectively.

Lone atrial fibrillation: where are we now?

PubMed

Potpara, Tatjana S; Lip, Gregory Y

2011-10-01

There is a growing pandemic of atrial fibrillation (AF), affecting nearly 2% of the general adult population. Atrial fibrillation is commonly associated with structural heart disease, and AF itself causes a sequence of complex processes of electrical, contractile, and structural remodeling of the atrial myocardium, which facilitate further AF progression. Nonetheless, AF may also affect individuals aged ≤ 65 years who have no evidence of associated cardiopulmonary or other disease, including hypertension; this is otherwise referred to as "lone" AF and is considered to have a generally favorable prognosis. The true prevalence of lone AF is unknown. Growing insights into the diversity of numerous mechanisms involved in the pathogenesis of AF, including acute atrial stretch, structural and electrophysiological alterations, systemic inflammation, oxidative stress, autonomic imbalance, genetic predisposition, and many others, and increasing recognition of novel risk factors for AF, including obesity, metabolic syndrome, subclinical atherosclerosis, sleep apnea, alcohol consumption, and endurance sports, suggest that apparently lone AF might not be so "lone" in many patients, which could have important prognostic and therapeutic implications. In this article, we summarize the current knowledge of epidemiology, etiopathogenesis, and pathophysiology of so-called lone AF and discuss the issues of long-term prognosis and management of patients who have an apparently lone AF.

How to perform posterior wall isolation in catheter ablation for atrial fibrillation.

PubMed

Sugumar, Hariharan; Thomas, Stuart P; Prabhu, Sandeep; Voskoboinik, Aleksandr; Kistler, Peter M

2018-02-01

Catheter ablation has become standard of care in patients with symptomatic atrial fibrillation (AF). Although there have been significant advances in our understanding and technology, a substantial proportion of patients have ongoing AF requiring repeat procedures. Pulmonary vein isolation (PVI) is the cornerstone of AF ablation; however, it is less effective in patients with persistent as opposed to paroxysmal atrial fibrillation. Left atrial posterior wall isolation (PWI) is commonly performed as an adjunct to PVI in patients with persistent AF with nonrandomized studies showing improved outcomes. Anatomical considerations and detailed outline of the various approaches and techniques to performing PWI are detailed, and advantages and pitfalls to assist the clinical electrophysiologist successfully and safely complete PWI are described. © 2017 Wiley Periodicals, Inc.

Comprehensive Mutation Scanning of LMNA in 268 Patients With Lone Atrial Fibrillation

PubMed Central

Brauch, Katharine M.; Chen, Lin Y.; Olson, Timothy M.

2009-01-01

Atrial fibrillation (AF) is a heritable, genetically heterogeneous disorder. To identify gene defects that cause or confer susceptibility to AF, a cohort of 268 unrelated patients with idiopathic forms of familial and sporadic AF was recruited. LMNA, encoding the nuclear membrane proteins, lamin A/C, was selected as a candidate gene for lone AF based on its established association with a syndrome of dilated cardiomyopathy, conduction system disease, and AF. Comprehensive mutation scanning identified only 1 potentially pathogenic mutation. In conclusion, LMNA mutations rarely cause lone AF and routine genetic testing of LMNA in these patients does not appear warranted. PMID:19427440

Oxidized CaMKII Triggers Atrial Fibrillation

PubMed Central

Purohit, Anil; Rokita, Adam G.; Guan, Xiaoqun; Chen, Biyi; Koval, Olha M.; Voigt, Niels; Neef, Stefan; Sowa, Thomas; Gao, Zhan; Luczak, Elizabeth D.; Stefansdottir, Hrafnhildur; Behunin, Andrew C.; Li, Na; El-Accaoui, Ramzi N.; Yang, Baoli; Swaminathan, Paari Dominic; Weiss, Robert M.; Wehrens, Xander H.T.; Song, Long-Sheng; Dobrev, Dobromir; Maier, Lars S.; Anderson, Mark E.

2013-01-01

Background Atrial fibrillation is a growing public health problem without adequate therapies. Angiotensin II (Ang II) and reactive oxygen species (ROS) are validated risk factors for atrial fibrillation (AF) in patients, but the molecular pathway(s) connecting ROS and AF is unknown. The Ca2+/calmodulin-dependent protein kinase II (CaMKII) has recently emerged as a ROS activated proarrhythmic signal, so we hypothesized that oxidized CaMKIIδ(ox-CaMKII) could contribute to AF. Methods and Results We found ox-CaMKII was increased in atria from AF patients compared to patients in sinus rhythm and from mice infused with Ang II compared with saline. Ang II treated mice had increased susceptibility to AF compared to saline treated WT mice, establishing Ang II as a risk factor for AF in mice. Knock in mice lacking critical oxidation sites in CaMKIIδ (MM-VV) and mice with myocardial-restricted transgenic over-expression of methionine sulfoxide reductase A (MsrA TG), an enzyme that reduces ox-CaMKII, were resistant to AF induction after Ang II infusion. Conclusions Our studies suggest that CaMKII is a molecular signal that couples increased ROS with AF and that therapeutic strategies to decrease ox-CaMKII may prevent or reduce AF. PMID:24030498

Atrial remodelling in atrial fibrillation: CaMKII as a nodal proarrhythmic signal

PubMed Central

Mesubi, Olurotimi O.; Anderson, Mark E.

2016-01-01

CaMKII is a serine–threonine protein kinase that is abundant in myocardium. Emergent evidence suggests that CaMKII may play an important role in promoting atrial fibrillation (AF) by targeting a diverse array of proteins involved in membrane excitability, cell survival, calcium homeostasis, matrix remodelling, inflammation, and metabolism. Furthermore, CaMKII inhibition appears to protect against AF in animal models and correct proarrhythmic, defective intracellular Ca2+ homeostasis in fibrillating human atrial cells. This review considers current concepts and evidence from animal and human studies on the role of CaMKII in AF. PMID:26762270

Catheter Ablation versus Thoracoscopic Surgical Ablation in Long Standing Persistent Atrial Fibrillation (CASA-AF): study protocol for a randomised controlled trial.

PubMed

Khan, Habib Rehman; Kralj-Hans, Ines; Haldar, Shouvik; Bahrami, Toufan; Clague, Jonathan; De Souza, Anthony; Francis, Darrel; Hussain, Wajid; Jarman, Julian; Jones, David Gareth; Mediratta, Neeraj; Mohiaddin, Raad; Salukhe, Tushar; Jones, Simon; Lord, Joanne; Murphy, Caroline; Kelly, Joanna; Markides, Vias; Gupta, Dhiraj; Wong, Tom

2018-02-20

Atrial fibrillation is the commonest arrhythmia which raises the risk of heart failure, thromboembolic stroke, morbidity and death. Pharmacological treatments of this condition are focused on heart rate control, rhythm control and reduction in risk of stroke. Selective ablation of cardiac tissues resulting in isolation of areas causing atrial fibrillation is another treatment strategy which can be delivered by two minimally invasive interventions: percutaneous catheter ablation and thoracoscopic surgical ablation. The main purpose of this trial is to compare the effectiveness and safety of these two interventions. Catheter Ablation versus Thoracoscopic Surgical Ablation in Long Standing Persistent Atrial Fibrillation (CASA-AF) is a prospective, multi-centre, randomised controlled trial within three NHS tertiary cardiovascular centres specialising in treatment of atrial fibrillation. Eligible adults (n = 120) with symptomatic, long-standing, persistent atrial fibrillation will be randomly allocated to either catheter ablation or thoracoscopic ablation in a 1:1 ratio. Pre-determined lesion sets will be delivered in each treatment arm with confirmation of appropriate conduction block. All patients will have an implantable loop recorder (ILR) inserted subcutaneously immediately following ablation to enable continuous heart rhythm monitoring for at least 12 months. The devices will be programmed to detect episodes of atrial fibrillation and atrial tachycardia ≥ 30 s in duration. The patients will be followed for 12 months, completing appropriate clinical assessments and questionnaires every 3 months. The ILR data will be wirelessly transmitted daily and evaluated every month for the duration of the follow-up. The primary endpoint in the study is freedom from atrial fibrillation and atrial tachycardia at the end of the follow-up period. The CASA-AF Trial is a National Institute for Health Research-funded study that will provide first-class evidence on the comparative efficacy, safety and cost-effectiveness of thoracoscopic surgical ablation and conventional percutaneous catheter ablation for long-standing persistent atrial fibrillation. In addition, the results of the trial will provide information on the effects on patients' quality of life. ISRCTN Registry, ISRCTN18250790 . Registered on 24 April 2015.

Termination of persistent atrial fibrillation during pulmonary vein isolation: insight from the MAGIC-AF trial.

PubMed

Singh, Sheldon M; d'Avila, Andre; Kim, Young-Hoon; Aryana, Arash; Mangrum, J Michael; Michaud, Gregory F; Dukkipati, Srinivas R; Barrett, Conor D; Heist, E Kevin; Parides, Michael K; Thorpe, Kevin E; Reddy, Vivek Y

2017-10-01

Controversy on the optimal ablation strategy for persistent atrial fibrillation (AF) exists with limited work evaluating a strategy of pulmonary vein isolation (PVI) alone when AF terminates during PVI. Thirty-five patients had AF termination during PVI in the Modified Ablation Guided by Ibutilide Use in Chronic Atrial Fibrillation (MAGIC-AF; ClinicalTrials.gov number: NCT01014741) study. The objective of the current study is to report the 1-year outcome after PVI alone in this unique patient group. The 1-year single procedure freedom from atrial arrhythmia off anti-arrhythmic drugs was reported for the 35 patients in the MAGIC-AF study with persistent AF termination during or upon completion of PVI. Freedom from recurrent atrial arrhythmia was achieved in 60% of patients where AF terminated during PVI. Cavotricuspid isthmus flutter was common when AF terminated to a macro re-entrant flutter during PVI, and responsible for 92% of all flutter circuits with AF termination. Persistent AF termination during PVI may identify a subgroup of patients who experience a similar long-term clinical outcome with PVI ablation alone when compared with other more extensive persistent AF ablation strategies. Pulmonary vein isolation alone may be an appropriate tactic in this subgroup of persistent AF patients. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

Racial and Ethnic Differences in the Prevalence, Management and Outcomes in Patients with Atrial Fibrillation: A Systematic Review.

PubMed

Ugowe, Francis E; Jackson, Larry R; Thomas, Kevin L

2018-05-23

Atrial Fibrillation (AF) is the most common cardiac arrhythmia in the United States (US) and is associated with increased morbidity, mortality, and healthcare expenditures. In this work, our aim was to assess for racial and ethnic differences in the epidemiology, management and outcomes of patients with AF. A search of relevant studies from January 1, 2007 to December 30, 2017 was conducted using PubMed, EMBASE, and Web of Science and supplemented by manual searches of the bibliographies of retrieved articles. We identified 152 studies of which 64 were subsequently included. We found underrepresented racial and ethnic groups (UREGs) have a higher prevalence of established risk factors associated with the development of AF, but an overall lower incidence and prevalence of AF compared with non-Hispanic whites (NHW). Moreover, racial and ethnic differences exist in detection, awareness and AF-associated symptoms. Non-white populations also experience decreased use of rhythm control modalities and anticoagulation for stroke prevention. Lastly, among those with AF, UREGs suffer increased morbidity and mortality relative to white groups. Racial and ethnic differences exist in the prevalence, quality of life, management and outcomes of individuals with AF; however, the mechanisms for these differences have yet to be fully elucidated. Racial and ethnic differences in AF warrant further analysis to understand the factors contributing to the differences in prevalence and management to ensure the delivery of high quality care that prevents stroke, reduces deaths and decreases expenses associated with caring for underrepresented populations with AF. Copyright © 2018. Published by Elsevier Inc.

[Validation of taking arterial pulse in Primary Care for the detection of atrial fibrillation and other cardiac rhythm disorders in patients over 65 years old].

PubMed

Pérula-de Torres, L A; González-Blanco V, V; Luque-Montilla, R; Martín-Rioboó, E; Martínez-Adell, M A; Ruiz-de Castroviejo, J

2017-09-01

Atrial fibrillation (AF) is the most frequent arrhythmia in clinical practice and has important prognostic implications. The objective of this study was to demonstrate the validity and the reliability of taking the arterial pulse (TAP) in patients over 65 years for detecting in AF and other rhythm disorders. A descriptive, observational, multicentre study to validate a diagnostic test within in a controlled clinical trial. 39 Primary Care Centres in the Spanish National Health Service. A total of 318 physicians and nurses took part in the analysis of validity, and 166 of them took part in the analysis of reliability. The professionals were previously called to a meeting in which they took the arterial pulses, and were given 4 ECGs to interpret. The participants TAP of 864 patients followed by an ECG to confirm the cardiac rhythm. Sensitivity, specificity and predictive values were estimated to assess the criterial validity and the simple concordance index to check reproducibility. The sensitivity of pulse measurement for detecting AF detection was 99.4% (95% CI: 97.9-100.0), with a specificity of 30.7% (95% CI: 26.1-35.3), a positive predictive value of 36.6% (95% CI 32.0-41.2), and negative predictive value of 99.2% (97.3-100.0). The simple concordance between the researchers and the cardiologist for the ECG diagnosis of AF ranged between 84.9% and 91.6%. The TAP has a high sensitivity but a low specificity to detect AF. It is a reliable test for the opportunistic screening of arrhythmias in patients aged over 65 years. Copyright © 2016 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España, S.L.U. All rights reserved.

[New technology for prevention of embolic events in atrial fibrillation: a systematic review on percutaneous endovascular left atrial appendage closure].

PubMed

Danna, Paolo; Sagone, Antonio; Proietti, Riccardo; Arensi, Andrea; Viecca, Maurizio; Santangeli, Pasquale; Di Biase, Luigi; Natale, Andrea

2012-09-01

Atrial fibrillation (AF) is the most common cardiac arrhythmia. The mortality rate of patients with AF is doubled as compared to non-fibrillating controls. The most relevant complication of AF is a major increase in the risk of stroke. The gold standard in reducing cerebrovascular events in AF is warfarin therapy, which is not free from contraindications and limitations. The left atrial appendage (LAA) is the main source of emboli causing stroke in AF. LAA closure is a seducing approach to stroke risk reduction in AF without anticoagulation. Since 1949, heart surgeons have performed LAA closure or amputation in patients with AF. Percutaneous endovascular LAA closure is a new, less invasive, technique to reach the goal. Several devices have been used to perform this intervention, and the results of published trials are encouraging in terms of effectiveness and relative safety of this attractive technique. In this review we examine the published trials and data on percutaneous LAA closure, with particular attention to the risks and benefits of this procedure.

Heart rate variability parameters in horses distinguish atrial fibrillation from sinus rhythm before and after successful electrical cardioversion.

PubMed

Broux, B; De Clercq, D; Decloedt, A; Ven, S; Vera, L; van Steenkiste, G; Mitchell, K; Schwarzwald, C; van Loon, G

2017-11-01

Atrial fibrillation (AF) is the most common pathological arrhythmia in horses. After successful treatment, recurrence is common. Heart rate monitors are easily applicable in horses and some devices offer basic heart rate variability (HRV) calculations. If HRV can be used to distinguish between AF and sinus rhythm (SR), this could become a monitoring tool for horses at risk for recurrence of AF. The purpose of this study was to assess whether in horses AF (before cardioversion) and SR (after cardioversion) can be differentiated based upon HRV parameters. Cohort study with internal controls. Six HRV parameters were determined in 20 horses, both in AF and in SR, at rest (2- and 5-min and 1- and 4-h recordings) and during exercise (walk and trot, 2-min recordings). Time-domain (standard deviation of the NN intervals, root mean squared successive differences in NN intervals and triangular index), frequency domain (low/high frequency ratio) and nonlinear parameters (standard deviation of the Poincaré plot [SD]1 and SD2) were used. Statistical analysis was done using paired Wilcoxon signed rank tests and receiver operating characteristic curves. HRV was higher during AF compared to SR. Results for the detection of AF were good (area under the receiver operating characteristic curve [AUC] 0.8-1) for most HRV parameters. Root mean squared successive differences in NN intervals and SD1 yielded the best results (AUC 0.9-1). Sensitivity and specificity were high for all parameters at all recordings, but highest during exercise. Although AUCs improved with longer recordings, short recordings were also good (AUC 0.8-1) for the detection of AF. In horses with frequent second degree atrioventricular block, HRV at rest is increased and recordings at walk or trot are recommended. Animals served as their own controls and there was no long-term follow-up to identify AF recurrence. AF (before cardioversion) and SR (after cardioversion) could be distinguished with HRV. This technique has promise as a monitoring tool in horses at risk for AF development. © 2017 EVJ Ltd.

Thromboembolic event rate in paroxysmal and persistent atrial fibrillation: Data from the GISSI-AF trial

PubMed Central

2013-01-01

Background Few data on the thromboembolic (TE) risk of paroxysmal and persistent atrial fibrillation (AF) are available. This study aimed to assess the incidence of TE events in paroxysmal and persistent AF. Methods We performed a subset post hoc analysis of 771 patients with paroxysmal and 463 with persistent AF enrolled in the multicenter, prospective, randomized, double-blind, placebo-controlled GISSI-AF trial - comparing the efficacy of valsartan versus placebo in preventing AF recurrences – where the choice of antithrombotic treatment was left to the judgment of the referring physician. TE and major outcome events were centrally validated. AF recurrences were detected by frequent clinic visits and a transtelephonic monitoring device with weekly and symptomatic transmissions. Results Eighty-five percent of patients had a history of hypertension, and the 7.7% had heart failure, left ventricular dysfunction, or both. The mean CHADS2 score was 1.41±0.84. TE and major bleeding events were observed at a low incidence among the overall population at 1-year follow-up (0.97% and 0.81%, respectively). The univariate and multivariable analyses revealed no statistically significant differences in the incidence of TE, major bleeding events or mortality in paroxysmal and persistent AF patients. TE events were more common among women than men (p=0.02). The follow-up examination showed under- or overtreatment with warfarin in many patients, according to guideline suggestions. Warfarin was more frequently prescribed to patients with persistent AF (p<0.0001) and patients with AF recurrences (p<0.0001). AF recurrences were noninvasively detected in 632 (51.2%) patients. In patients without AF recurrences, the TE event rate was 0.5% versus 1.74%, 1.28%, and 1.18% for those with only symptomatic, only asymptomatic or both symptomatic and asymptomatic AF recurrences, respectively, but the difference was not statistically significant, even after adjusting for warfarin treatment and the CHADS2 score (HR 2.93; CI 95%; 0.8-10.9; p=0.11). Conclusions TE and major bleeding events showed a very low incidence in the GISSI-AF trial population, despite under- or overtreatment with warfarin in many patients. TE events had a similar rate in paroxysmal and persistent AF. Trial registration Trial registration number: NCT00376272 PMID:23586654

Rationale and design of a home-based trial using wearable sensors to detect asymptomatic atrial fibrillation in a targeted population: The mHealth Screening To Prevent Strokes (mSToPS) trial.

PubMed

Steinhubl, Steven R; Mehta, Rajesh R; Ebner, Gail S; Ballesteros, Marissa M; Waalen, Jill; Steinberg, Gregory; Van Crocker, Percy; Felicione, Elise; Carter, Chureen T; Edmonds, Shawn; Honcz, Joseph P; Miralles, Gines Diego; Talantov, Dimitri; Sarich, Troy C; Topol, Eric J

2016-05-01

Efficient methods for screening populations for undiagnosed atrial fibrillation (AF) are needed to reduce its associated mortality, morbidity, and costs. The use of digital technologies, including wearable sensors and large health record data sets allowing for targeted outreach toward individuals at increased risk for AF, might allow for unprecedented opportunities for effective, economical screening. The trial's primary objective is to determine, in a real-world setting, whether using wearable sensors in a risk-targeted screening population can diagnose asymptomatic AF more effectively than routine care. Additional key objectives include (1) exploring 2 rhythm-monitoring strategies-electrocardiogram-based and exploratory pulse wave-based-for detection of new AF, and (2) comparing long-term clinical and resource outcomes among groups. In all, 2,100 Aetna members will be randomized 1:1 to either immediate or delayed monitoring, in which a wearable patch will capture a single-lead electrocardiogram during the first and last 2 weeks of a 4-month period beginning immediately or 4 months after enrollment, respectively. An observational, risk factor-matched control group (n = 4,000) will be developed from members who did not receive an invitation to participate. The primary end point is the incidence of new AF in the immediate- vs delayed-monitoring arms at the end of the 4-month monitoring period. Additional efficacy and safety end points will be captured at 1 and 3 years. The results of this digital medicine trial might benefit a substantial proportion of the population by helping identify and refine screening methods for undiagnosed AF. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Family history of atrial fibrillation as a predictor of atrial substrate and arrhythmia recurrence in patients undergoing atrial fibrillation catheter ablation.

PubMed

Kapur, Sunil; Kumar, Saurabh; John, Roy M; Stevenson, William G; Tedrow, Usha B; Koplan, Bruce A; Epstein, Laurence M; MacRae, Calum A; Michaud, Gregory F

2018-06-01

A commonly held notion is that patients with a family history of atrial fibrillation (AF) have worse atrial substrate and higher rates of arrhythmia recurrence following ablation. We sought to examine differences in atrial substrate and catheter ablation outcomes in patients with a 1st degree family member with paroxysmal or persistent AF (PeAF) compared to those without. A total of 256 consecutive patients undergoing their 1st ablation for AF (123 paroxysmal, 133 persistent) with >1 year follow up were included. The presence of one 1st-degree family relative was defined as a 'positive family history'. Clinical characteristics, electroanatomic map findings, ablation characteristics and outcomes were compared in patients with and without a positive family history of AF. Patients with paroxysmal fibrillation with a positive family history (n = 57; 46%) had similar clinical characteristics and arrhythmia recurrence after catheter ablation as those without. Of those that recurred, patients with a positive family history were more likely to have progressed to PeAF (P = 0.05). Patients with PeAF with a positive family history (n = 75; 56%) had similar clinical characteristics, electroanatomic mapping findings and ablation characteristics, but worse long term arrhythmia free survival (P = 0.04). The presence of a 1st-degree family member with AF does not impact the clinical outcomes of catheter ablation for paroxysmal AF. However, a positive family history is associated with worse arrhythmia free survival in patients with PeAF. This finding is not explained by differences in clinical characteristics, atrial substrate assessed by voltage maps or ablation characteristics.

Mineralocorticoid Receptor Antagonism in Patients With Atrial Fibrillation: Findings From the ORBIT-AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation) Registry.

PubMed

Fudim, Marat; Liu, Peter R; Shrader, Peter; Blanco, Rosalia G; Allen, Larry A; Fonarow, Gregg C; Gersh, Bernard J; Kowey, Peter R; Mahaffey, Kenneth W; Hylek, Elaine; Go, Alan S; Thomas, Laine; Peterson, Eric D; Piccini, Jonathan P

2018-04-13

Mineralocorticoid receptor antagonist (MRA) therapy may be beneficial to patients with atrial fibrillation (AF), but little is known about their use in patients with AF and subsequent outcomes. In order to better understand MRA use and subsequent outcomes, we performed a retrospective cohort study of the contemporary ORBIT-AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation) registry. AF progression and cardiovascular outcomes were compared using propensity-matched Cox proportional hazards modeling according to MRA use at baseline and new MRA use at follow-up versus patients with no MRA use. Among 7012 patients with nonpermanent AF, 320 patients were taking MRA at enrollment, and 416 patients initiated MRA use during follow-up. The mean patient age was 72.5 years, 56.3% were men, and 70.4% had paroxysmal AF. Among all patients taking MRAs, 434 (59.0%) had heart failure, 655 (89.0%) had hypertension, and 380 (51.6%) had both. After adjustment, new MRA use was not associated with reduced AF progression (hazard ratio, 1.18; 95% confidence interval, 0.88-1.58; P =0.27) but showed a trend towards lower risk of stroke, transient ischemic attack, or systemic embolism (hazard ratio, 0.17; 95% confidence interval, 0.02-1.23; P =0.08). Results were similar for a comparison of new MRA users and baseline MRA users compared with nonusers. In community-based outpatients with AF, the majority of MRA use was for heart failure and hypertension. MRA use also trended towards lower adjusted stroke risk. Future studies should test the hypothesis that MRA use may decrease the risk of stroke in patients with AF. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Clinical and electrocardiographic characteristics for prediction of new-onset atrial fibrillation in asymptomatic patients with atrial premature complexes.

PubMed

Im, Sung Il; Park, Dong Hyun; Kim, Bong Joon; Cho, Kyoung Im; Kim, Hyun Su; Heo, Jung Ho

2018-06-01

Identification of precursors of atrial fibrillation (AF) may lead to early detection and prevent associated morbidity and mortality. Atrial premature complexes (APCs) are commonly seen in healthy subjects. However, there was limited data about the clinical and electrocardiographic (ECG) characteristics for prediction of new-onset AF in asymptomatic patients with APCs in the long-term follow up. The Kosin University (No. 2014-02-04) 24-h holter monitoring, echocardiography, ECG database were reviewed from 2008 to 2016 to identify new- onset AF in patients with APCs. We analyzed demographic and clinical features and the nature of the APCs by ECG according to new-onset AF in those patients. Among 652 patients who underwent 24-h holter monitoring, 226 (34.4%) patients had new-onset AF. There was no difference of the baseline characteristics between new-onset AF group and non-AF group. In univariate analysis, hypertension (HTN), renal failure (CRF), high APC burdens, fastest APC running heart rate (HR), minimal HR, left ventricular ejection fraction (LVEF), left atrial volume index, peak mitral flow velocity of the early rapid filling wave and tricuspid regurgitation grade were significantly associated with new-onset AF. In multivariate analysis, higher APCs burden ( P  = 0.047), higher fastest APCs running HR ( P  = 0.034) and lower minimal HR ( P  = 0.025) were independent risk factors for new-onset AF in asymptomatic patients with APCs. Higher APCs burden, higher fastest APCs running HR and lower minimal HR were associated with new-onset AF in asymptomatic patients with APCs in the long-term follow up.

Atrial ectopy predicts late recurrence of atrial fibrillation after pulmonary vein isolation.

PubMed

Gang, Uffe J O; Nalliah, Chrishan J; Lim, Toon Wei; Thiagalingam, Aravinda; Kovoor, Pramesh; Ross, David L; Thomas, Stuart P

2015-06-01

Late recurrence of atrial fibrillation (AF) after radiofrequency ablation remains significant. Asymptomatic recurrence poses a difficult clinical problem as it is associated with an equally increased risk of stroke and death compared with symptomatic AF events. Meta-analyses reveal that no single preablation patient characteristic efficiently predicts these AF recurrences. This study aimed to evaluate the prognostic value of premature atrial complex (PAC) occurrence with regard to the risk of late AF recurrence after radiofrequency ablation. The study cohort consisted of 124 patients with 7-day Holter recordings at 6 months post radiofrequency ablation for AF. No patients had AF recurrence before this time. Patients were followed-up every 6 months. Holter-detected PACs were defined as any supraventricular complexes occurring >30% earlier than expected. During a median follow-up of 4.2 years (first quartile to third quartile [Q1-Q3]=1.6-4.5), 32 patients (26%) had late recurrences of AF at a median of 462 days (Q1-Q3=319-1026) post radiofrequency ablation. The number of PACs per 24 hours was 248 (Q1-Q3=62-1026) in patients with and 77 (Q1-Q3=24-448) in patients without recurrence of AF (P=0.02). Multivariate analysis of the risk of late AF recurrence found ≥142 PACs per 24 hours to have a hazard ratio 2.84 (confidence interval, 1.26-6.43), P=0.01. This study showed that occurrence of ≥142 PACs per day at 6 months after PVI was independently associated with a significantly increased risk of late AF recurrence. These results could have important clinical implications for the design of post-PVI follow-up. URL: http://www.anzctr.org.au. Unique identifier: ACRTN12606000467538. © 2015 American Heart Association, Inc.

Left atrial pressure pattern without a-wave in sinus rhythm after cardioversion affects the outcomes after catheter ablation for atrial fibrillation.

PubMed

Kishima, Hideyuki; Mine, Takanao; Takahashi, Satoshi; Ashida, Kenki; Ishihara, Masaharu; Masuyama, Tohru

2018-04-24

The a-wave in left atrial pressure (LAP) is often not observed after cardioversion (CV). We hypothesized that repeated atrial fibrillation (AF) occurs in patients who do not show a-wave pattern after CV. We investigated the impact of "LAP pattern without a-wave" on the outcome after catheter ablation (CA) for AF. We studied 100 patients (64 males, age 66 ± 8 years, 42 with non-paroxysmal AF) who underwent CA for AF. Sustained- or induced-AF were terminated with internal CV, and LAP was measured during sinus rhythm (SR) after CV. LAP pattern without a-wave was defined as absence of a-wave (the "a-wave" was defined as a protruding part by 0.2 mmHg or more from the baseline) in LAP wave form. AF was terminated with CV in all patients. Recurrent AF was detected in 35/100 (35%) during the follow-up period (13.1 ± 7.8 month). Univariate analysis revealed higher prevalence of LAP pattern without a-wave (71 vs. 17%, P < 0.0001), larger left atrial volume, elevated E wave, and decreased deceleration time as significant variables. On multivariate analysis, LAP pattern without a-wave was only independently associated with recurrent AF (P = 0.0014, OR 9.865, 95% CI 2.327-54.861). Moreover, patients with LAP pattern without a-wave had a higher risk of recurrent AF than patients with a-wave (25/36 patients, 69 vs. 10/64 patients, 16%, log-rank P < 0.0001). Left atrial pressure pattern without a-wave in sinus rhythm after cardioversion could predict recurrence after catheter ablation for AF.

Irregularity and lack of p waves in short tachycardia episodes predict atrial fibrillation and ischemic stroke.

PubMed

Johnson, Linda S B; Persson, Anders P; Wollmer, Per; Juul-Möller, Steen; Juhlin, Tord; Engström, Gunnar

2018-02-13

Atrial fibrillation (AF) is defined as an irregular supraventricular tachycardia (SVT) without p waves, with duration >30 seconds. Whether AF characteristics during short SVT episodes predict AF and stroke is not known. The purpose of this study was to determine whether irregularity and lack of p waves, alone or in combination, during short SVT episodes increase the risk of incident AF and ischemic stroke. The population-based Malmö Diet and Cancer study includes 24-hour ECG screening of 377 AF-free individuals (mean age 64.5 years; 43% men) who were prospectively followed for >13 years. There were 65 AF events and 25 ischemic stroke events during follow-up. Subjects with an SVT episode ≥5 beats were identified, and the longest SVT episode was assessed for irregularity and lack of p waves. The association between SVT classification and AF and stroke was assessed using multivariable adjusted Cox regression. The incidence of AF increased with increasing abnormality of the SVTs. The risk-factor adjusted hazard ratio for AF was 4.95 (95% confidence interval 2.06-11.9; P <.0001) for those with short irregular SVTs (<70 beats) without p waves. The incidence of ischemic stroke was highest in the group with regular SVT episodes without p waves (hazard ratio 14.2; 95% confidence interval 3.76-57.6; P <.0001, adjusted for age and sex). Characteristics of short SVT episodes detected at 24-hour ECG screening are associated with incident AF and ischemic stroke. Short irregular SVTs without p waves likely represent early stages of AF or atrial myopathy. Twenty-four-hour ECG could identify subjects suitable for primary prevention efforts. Copyright © 2018 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Wireless monitoring of reconstructed 12-lead ECG in atrial fibrillation patients enables differential diagnosis of recurrent arrhythmias.

PubMed

Vukajlovic, Dejan; Gussak, Ihor; George, Samuel; Simic, Goran; Bojovic, Bosko; Hadzievski, Ljupco; Stojanovic, Bojan; Angelkov, Lazar; Panescu, Dorin

2011-01-01

Differential diagnosis of symptomatic events in post-ablation atrial fibrillation (AF) patients (pts) is important; in particular, accurate, reliable detection of AF or atrial flutter (AFL) is essential. However, existing remote monitoring devices usually require attached leads and are not suitable for prolonged monitoring; moreover, most do not provide sufficient information to assess atrial activity, since they generally monitor only 1-3 ECG leads and rely on RR interval variability for AF diagnosis. A new hand-held, wireless, symptom-activated event monitor (CardioBip; CB) does not require attached leads and hence can be conveniently used for extended periods. Moreover, CB provides data that enables remote reconstruction of full 12-lead ECG data including atrial signal information. We hypothesized that these CB features would enable accurate remote differential diagnosis of symptomatic arrhythmias in post-ablation AF pts. 21 pts who underwent catheter ablation for AF were instructed to make a CB transmission (TX) whenever palpitations, lightheadedness, or similar symptoms occurred, and at multiple times daily when asymptomatic, during a 60 day post-ablation time period. CB transmissions (TXs) were analyzed blindly by 2 expert readers, with differences adjudicated by consensus. 7 pts had no symptomatic episodes during the monitoring period. 14 of 21 pts had symptomatic events and made a total of 1699 TX, 164 of which were during symptoms. TX quality was acceptable for rhythm diagnosis and atrial activity in 96%. 118 TX from 10 symptomatic pts showed AF (96 TX from 10 pts) or AFL (22 TX from 3 pts), and 46 TX from 9 pts showed frequent PACs or PVCs. No other arrhythmias were detected. Five pts made symptomatic TX during AF/AFL and also during PACs/PVCs. Use of CB during symptomatic episodes enabled detection and differential diagnosis of symptomatic arrhythmias. The ability of CB to provide accurate reconstruction of 12 L ECGs including atrial activity, combined with its ease of use, makes it suitable for long-term surveillance for recurrent AF in post-ablation patients.

Targeting Stable Rotors to Treat Atrial Fibrillation.

PubMed

Narayan, Sanjiv M; Krummen, David E

2012-09-01

Therapy for atrial fibrillation (AF) remains suboptimal, in large part because its mechanisms are unclear. While pulmonary vein ectopy may trigger AF, it remains uncertain how AF, once triggered, is actually sustained. Recent discoveries show that human AF is maintained by a small number of rotors or focal sources. AF sources are widely distributed in patient-specific locations, often remote from pulmonary veins and in the right atrium and stable for prolonged periods of time. In a multicentre experience, brief targeted ablation at sources (focal impulse and rotor modulation [FIRM]) terminated AF predominantly to sinus rhythm prior to pulmonary vein isolation and eliminated AF on rigorous followup. This review summarises the evidence for stable rotors and focal sources of human AF and their clinical role as ablation targets to eliminate paroxysmal, persistent and long-standing persistent AF.

Obstructive Sleep Apnoea and Atrial Fibrillation

PubMed Central

Zhang, Ling; Hou, Yuemei; Po, Sunny S

2015-01-01

Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia and is associated with significant morbidity and mortality. Obstructive sleep apnoea (OSA) is common among patients with AF. Growing evidence suggests that OSA is associated with the initiation and maintenance of AF. This association is independent of obesity, body mass index and hypertension. OSA not only promotes initiation of AF but also has a significant negative impact on the treatment of AF. Patients with untreated OSA have a higher AF recurrence rate with drug therapy, electrical cardioversion and catheter ablation. Treatment with continuous positive airway pressure (CPAP) has been shown to improve AF control in patients with OSA. In this article, we will review and discuss the pathophysiological mechanisms of OSA that may predispose OSA patients to AF as well as the standard and emerging therapies for patients with both OSA and AF. PMID:26835094

Atrial fibrillation

PubMed Central

Munger, Thomas M.; Wu, Li-Qun; Shen, Win K.

2014-01-01

Atrial fibrillation is the most common arrhythmia affecting patients today. Disease prevalence is increasing at an alarming rate worldwide, and is associated with often catastrophic and costly consequences, including heart failure, syncope, dementia, and stroke. Therapies including anticoagulants, anti-arrhythmic medications, devices, and non-pharmacologic procedures in the last 30 years have improved patients' functionality with the disease. Nonetheless, it remains imperative that further research into AF epidemiology, genetics, detection, and treatments continues to push forward rapidly as the worldwide population ages dramatically over the next 20 years. PMID:24474959

Real-Time Rotational Activity Detection in Atrial Fibrillation

PubMed Central

Ríos-Muñoz, Gonzalo R.; Arenal, Ángel; Artés-Rodríguez, Antonio

2018-01-01

Rotational activations, or spiral waves, are one of the proposed mechanisms for atrial fibrillation (AF) maintenance. We present a system for assessing the presence of rotational activity from intracardiac electrograms (EGMs). Our system is able to operate in real-time with multi-electrode catheters of different topologies in contact with the atrial wall, and it is based on new local activation time (LAT) estimation and rotational activity detection methods. The EGM LAT estimation method is based on the identification of the highest sustained negative slope of unipolar signals. The method is implemented as a linear filter whose output is interpolated on a regular grid to match any catheter topology. Its operation is illustrated on selected signals and compared to the classical Hilbert-Transform-based phase analysis. After the estimation of the LAT on the regular grid, the detection of rotational activity in the atrium is done by a novel method based on the optical flow of the wavefront dynamics, and a rotation pattern match. The methods have been validated using in silico and real AF signals. PMID:29593566

Multifractal analysis for grading complex fractionated electrograms in atrial fibrillation.

PubMed

Orozco-Duque, A; Novak, D; Kremen, V; Bustamante, J

2015-11-01

Complex fractionated atrial electrograms provide an important tool for identifying arrhythmogenic substrates that can be used to guide catheter ablation for atrial fibrillation (AF). However, fractionation is a phenomenon that remains unclear. This paper aims to evaluate the multifractal properties of electrograms in AF in order to propose a method based on multifractal analysis able to discriminate between different levels of fractionation. We introduce a new method, the h-fluctuation index (hFI), where h is the generalised Hurst exponent, to extract information from the shape of the multifractal spectrum. Two multifractal frameworks are evaluated: multifractal detrended fluctuation analysis and wavelet transform modulus maxima. hFI is exemplified through its application in synthetic signals, and it is evaluated in a database of electrograms labeled on the basis of four degrees of fractionation. We compare the performance of hFI with other indexes, and find that hFI outperforms them. The results of the study provide evidence that multifractal analysis is useful for studying fractionation phenomena in AF electrograms, and indicate that hFI can be proposed as a tool for grade fractionation associated with the detection of target sites for ablation in AF.

Treatment of Atrial Fibrillation By The Ablation Of Localized Sources

PubMed Central

Narayan, Sanjiv M.; Krummen, David E.; Shivkumar, Kalyanam; Clopton, Paul; Rappel, Wouter-Jan; Miller, John M.

2012-01-01

Objectives We hypothesized that human atrial fibrillation (AF) may be sustained by localized sources (electrical rotors and focal impulses), whose elimination (Focal Impulse and Rotor Modulation, FIRM) may improve outcome from AF ablation. Background Catheter ablation for AF is a promising therapy, whose success is limited in part by uncertainty in the mechanisms that sustain AF. We developed a computational approach to map whether AF is sustained by several meandering waves (the prevailing hypothesis) or localized sources, then prospectively tested whether targeting patient-specific mechanisms revealed by mapping would improve AF ablation outcome. Methods We recruited 92 individuals during 107 consecutive ablation procedures for paroxysmal or persistent (72%) AF. Cases were prospectively treated, in a 2-arm 1:2 design, by ablation at sources (FIRM-Guided) followed by conventional ablation (n=36), or conventional ablation alone (n=71; FIRM-Blinded). Results Localized rotors or focal impulses were detected in 98 (97%) of 101 cases with sustained AF, each exhibiting 2.1±1.0 sources. The acute endpoint (AF termination or consistent slowing) was achieved in 86% of FIRM-guided versus 20% of FIRM-Blinded cases (p<0.001). FIRM ablation alone at the primary source terminated AF in 2.5 minutes (median; IQR 1.0–3.1). Total ablation time did not differ between groups (57.8±22.8 versus 52.1±17.8 minutes, p=0.16). During 273 days (median; IQR 132–681 days) after a single procedure, FIRM-Guided cases had higher freedom from AF (82.4% versus 44.9%; p<0.001) after a single procedure than FIRM-blinded cases with rigorous, often implanted, ECG monitoring. Adverse events did not differ between groups. CONCLUSIONS Localized electrical rotors and focal impulse sources are prevalent sustaining-mechanisms for human AF. FIRM ablation at patient-specific sources acutely terminated or slowed AF, and improved outcome. These results offer a novel mechanistic framework and treatment paradigm for AF. (ClinicalTrials.gov number, NCT01008722) PMID:22818076

Electrophysiologic studies in atrial fibrillation. Slow conduction of premature impulses: a possible manifestation of the background for reentry.

PubMed

Cosio, F G; Palacios, J; Vidal, J M; Cocina, E G; Gómez-Sánchez, M A; Tamargo, L

1983-01-01

Extrastimulus-induced intraatrial conduction delays were measured in 12 patients with documented episodes of atrial fibrillation (AF) by recording atrial electrograms at the high right atrium, His bundle region, and coronary sinus. Seventeen patients with and without heart disease, but without atrial arrhythmias served as the control group. During baseline-paced atrial rhythms, a conduction delay zone could be delineated, near the atrial effective refractory period, during which all extrastimuli produced conduction delays. When compared at the same paced cycle lengths (500 to 650 ms), the patients with AF had shorter atrial effective refractory periods (mean +/- standard deviation 206 +/- 24.1 versus 233 +/- 28.2 in control patients, p less than 0.02), wider conduction delay zones (79 +/- 21.7 ms versus 52 +/- 21 in control patients, p less than 0.01), and longer conduction delays both to the His bundle region (64 +/- 18.3 ms versus 35 +/- 21.7 in control patients, p less than 0.005) and the coronary sinus (76 +/- 18.9 ms versus 35 +/- 16.1 in control patients, p less than 0.001). Repetitive atrial responses were recorded in 6 patients with AF and in 9 control subjects. Sinus nodal function abnormalities were detected in 6 of the patients with fibrillation. Patients with AF had a higher tendency than control subjects to develop slow intraatrial conduction, as well as shorter effective refractory periods. Since both features would favor reentry, they may be the electrophysiologic manifestations of the abnormalities making these patients prone to atrial reentrant arrhythmias. Repetitive atrial responses were of no predictive value. Sinus nodal dysfunction was frequently found, but was not essential for the occurrence of AF.

Pulmonary vein anatomy predicts freedom from atrial fibrillation using remote magnetic navigation for circumferential pulmonary vein ablation.

PubMed

Sohns, Christian; Sohns, Jan M; Bergau, Leonard; Sossalla, Samuel; Vollmann, Dirk; Lüthje, Lars; Staab, Wieland; Dorenkamp, Marc; Harrison, James L; O'Neill, Mark D; Lotz, Joachim; Zabel, Markus

2013-08-01

Multidetector computed tomography (MDCT) is frequently used to guide circumferential pulmonary vein ablation (PVA) for treatment of atrial fibrillation (AF) as it offers accurate visualization of the left atrial (LA) and pulmonary vein (PV) anatomy. This study aimed to identify if PV anatomy is associated with outcomes following PVA using remote magnetic navigation (RMN). We analysed data from 138 consecutive patients and 146 ablation procedures referred for PVA due to drug-refractory symptomatic AF (age 63 ± 11 years; 57% men; 69% paroxysmal AF). The RMN using the stereotaxis system and open-irrigated 3.5 mm ablation catheters was used in all procedures. Prior to PVA, all patients underwent electrocardiogram-gated 64-MDCT for assessment of LA dimensions, PV anatomy, and electro-anatomical image integration during the procedure. Regular PV anatomy was found in 68%, a common left PV ostium was detected in 26%, and variant anatomy of the right PVs was detected in 6%. After a mean follow-up of 337 ± 102 days, 63% of the patients maintained sinus rhythm after the initial ablation, and 83% when including repeat PVA. Although acutely successful PV isolation did not differ between anatomical subgroups (regular 3.5 ± 0.8 vs. variant 3.2 ± 1.3; P = 0.31), AF recurrence was significantly higher in patients with non-regular PV anatomy (P = 0.04, hazard ratio 1.72). Pulmonary vein anatomy did not influence complication rates. Pulmonary vein anatomy assessed by MDCT is a good predictor of AF recurrence after PVA using RMN.

Atrial Fibrillation - A Common Ground for Neurology and Cardiology.

PubMed

Abukhalil, Fawzi; Bodhit, Aakash; Cai, Peter Y; Ansari, Saeed; Thenkabail, Spandana; Ganji, Sarah; Saravanapavan, Pradeepan; Chandra Shekhar, Chandana; Waters, Michael F; Beaver, Thomas M; Shushrutha Hedna, Vishnumurthy

2013-01-01

Atrial fibrillation (AF) has a huge impact on clinical stroke because it is the primary cause of cardio-embolism, which constitutes ~20% of all strokes. As a result, there is a great need to explore safer and more effective primary and secondary prophylactic agents. In this article, we discuss the overlapping issues pertaining to AF from both a neurology and cardiology standpoint. We focus on the dynamic interplay of neurovascular and cardiovascular diseases in relation to AF, traditional and novel risk factors for AF leading to stroke, impact of AF on cognitive decline, and current upstream medical and surgical options for embolism prophylaxis.

Quality of Life in Atrial Fibrillation: Measurement Tools and Impact of Interventions

PubMed Central

REYNOLDS, MATTHEW R.; ELLIS, ETHAN; ZIMETBAUM, PETER

2008-01-01

QoL in AF. Quality of life (QoL) is of central importance in atrial fibrillation as both a treatment goal and an endpoint in the evaluation of new therapies. QoL appears to be impaired in the majority of patients with AF. A number of interventions for AF have been shown to improve QoL, including pharmacologic and nonpharmacologic rate control, antiarrhythmic drugs, and nonpharmacologic rhythm control strategies. This paper will review the rationale, design, strengths, and limitations of the questionnaires most commonly used to assess QoL in AF studies, and present QoL outcomes from major studies of AF interventions. PMID:18266667

Risk of ischemic stroke after atrial fibrillation diagnosis: A national sample cohort

PubMed Central

Son, Mi Kyoung; Lim, Nam-Kyoo; Kim, Hyung Woo

2017-01-01

Atrial fibrillation (AF) is a major risk factor for ischemic stroke and associated with a 5-fold higher risk of stroke. In this retrospective cohort study, the incidence of and risk factors for ischemic stroke in patients with AF were identified. All patients (≥30 years old) without previous stroke who were diagnosed with AF in 2007–2013 were selected from the National Health Insurance Service-National Sample Cohort. To identify factors that influenced ischemic stroke risk, Cox proportional hazard regression analysis was conducted. During a mean follow-up duration of 3.2 years, 1022 (9.6%) patients were diagnosed with ischemic stroke. The overall incidence rate of ischemic stroke was 30.8/1000 person-years. Of all the ischemic stroke that occurred during the follow-up period, 61.0% occurred within 1-year after AF diagnosis. Of the patients with CHA2DS2-VASc score of ≥2, only 13.6% were receiving warfarin therapy within 30 days after AF diagnosis. Relative to no antithrombotic therapy, warfarin treatment for >90 days before the index event (ischemic stroke in stroke patients and death/study end in non-stroke patients) associated with decreased ischemic stroke risk (Hazard Ratio = 0.41, 95%confidence intervals = 0.32–0.53). Heart failure, hypertension, and diabetes mellitus associated with greater ischemic stroke risk. AF patients in Korea had a higher ischemic stroke incidence rate than patients in other countries and ischemic stroke commonly occurred at early phase after AF diagnosis. Long-term (>90 days) continuous warfarin treatment may be beneficial for AF patients. However, warfarin treatment rates were very low. To prevent stroke, programs that actively detect AF and provide anticoagulation therapy are needed. PMID:28636620

Cardiac Magnetic Resonance-Measured Left Atrial Volume and Function and Incident Atrial Fibrillation: Results From MESA (Multi-Ethnic Study of Atherosclerosis).

PubMed

Habibi, Mohammadali; Samiei, Sanaz; Ambale Venkatesh, Bharath; Opdahl, Anders; Helle-Valle, Thomas M; Zareian, Mytra; Almeida, Andre L C; Choi, Eui-Young; Wu, Colin; Alonso, Alvaro; Heckbert, Susan R; Bluemke, David A; Lima, João A C

2016-08-01

Early detection of structural changes in left atrium (LA) before atrial fibrillation (AF) development could be helpful in identification of those at higher risk for AF. Using cardiac magnetic resonance imaging, we examined the association of LA volume and function, and incident AF in a multiethnic population free of clinical cardiovascular diseases. In a case-cohort study embedded in MESA (Multi-Ethnic Study of Atherosclerosis), baseline LA size and function assessed by cardiac magnetic resonance feature-tracking were compared between 197 participants with incident AF and 322 participants randomly selected from the whole MESA cohort. Participants were followed up for 8 years. Incident AF cases had a larger LA volume and decreased passive, active, and total LA emptying fractions and peak global LA longitudinal strain (peak LA strain) at baseline. In multivariable analysis, elevated LA maximum volume index (hazard ratio, 1.38 per SD; 95% confidence interval, 1.01-1.89) and decreased peak LA strain (hazard ratio, 0.68 per SD; 95% confidence interval, 0.48-0.96), and passive and total LA emptying fractions (hazard ratio for passive LA emptying fractions, 0.55 per SD; 95% confidence interval, 0.40-0.75 and hazard ratio for active LA emptying fractions, 0.70 per SD; 95% confidence interval, 0.52-0.95), but not active LA emptying fraction, were associated with incident AF. Elevated LA volumes and decreased passive and total LA emptying fractions were independently associated with incident AF in an asymptomatic multiethnic population. Including LA functional variables along with other risk factors of AF may help to better risk stratify individuals at risk of AF development. © 2016 American Heart Association, Inc.

Cardioembolic vs. noncardioembolic strokes in atrial fibrillation: frequency and effect of antithrombotic agents in the stroke prevention in atrial fibrillation studies.

PubMed

Hart, R G; Pearce, L A; Miller, V T; Anderson, D C; Rothrock, J F; Albers, G W; Nasco, E

2000-01-01

While atrial fibrillation (AF) increases the risk of cardioembolic stroke, some ischemic strokes in AF patients are noncardioembolic. To assess ischemic stroke mechanisms in AF and to compare their responses to antithrombotic therapies. On-therapy analyses of ischemic strokes occurring in 3,950 participants in the Stroke Prevention in Atrial Fibrillation I-III clinical trials. Strokes were classified by presumed mechanism according to specified neurologic features by neurologists unaware of antithrombotic therapy. Of 217 ischemic strokes, 52% were classified as probably cardioembolic, 24% as noncardioembolic, and 24% as of uncertain cause (i.e., 68% of classifiable infarcts were deemed cardioembolic). Compared to those receiving placebo or no antithrombotic therapy, the proportion of cardioembolic stroke was lower in patients taking adjusted-dose warfarin (p = 0.02), while the proportion of noncardioembolic stroke was lower in those taking aspirin (p = 0.06). Most (56%) ischemic strokes occurring in AF patients taking adjusted-dose warfarin were noncardioembolic vs. 16% of strokes in those taking aspirin. Adjusted-dose warfarin reduced cardioembolic strokes by 83% (p < 0.001) relative to aspirin. Cardioembolic strokes were particularly disabling (p = 0.05). Most ischemic strokes in AF patients are probably cardioembolic, and these are sharply reduced by adjusted-dose warfarin. Aspirin in AF patients appears to primarily reduce noncardioembolic strokes. AF patients at highest risk for stroke have the highest rates of cardioembolic stroke and have the greatest reduction in stroke by warfarin. Copyright 2000 S. Karger AG, Basel

Arrhythmia Evaluation in Wearable ECG Devices

PubMed Central

Sadrawi, Muammar; Lin, Chien-Hung; Hsieh, Yita; Kuo, Chia-Chun; Chien, Jen Chien; Haraikawa, Koichi; Abbod, Maysam F.; Shieh, Jiann-Shing

2017-01-01

This study evaluates four databases from PhysioNet: The American Heart Association database (AHADB), Creighton University Ventricular Tachyarrhythmia database (CUDB), MIT-BIH Arrhythmia database (MITDB), and MIT-BIH Noise Stress Test database (NSTDB). The ANSI/AAMI EC57:2012 is used for the evaluation of the algorithms for the supraventricular ectopic beat (SVEB), ventricular ectopic beat (VEB), atrial fibrillation (AF), and ventricular fibrillation (VF) via the evaluation of the sensitivity, positive predictivity and false positive rate. Sample entropy, fast Fourier transform (FFT), and multilayer perceptron neural network with backpropagation training algorithm are selected for the integrated detection algorithms. For this study, the result for SVEB has some improvements compared to a previous study that also utilized ANSI/AAMI EC57. In further, VEB sensitivity and positive predictivity gross evaluations have greater than 80%, except for the positive predictivity of the NSTDB database. For AF gross evaluation of MITDB database, the results show very good classification, excluding the episode sensitivity. In advanced, for VF gross evaluation, the episode sensitivity and positive predictivity for the AHADB, MITDB, and CUDB, have greater than 80%, except for MITDB episode positive predictivity, which is 75%. The achieved results show that the proposed integrated SVEB, VEB, AF, and VF detection algorithm has an accurate classification according to ANSI/AAMI EC57:2012. In conclusion, the proposed integrated detection algorithm can achieve good accuracy in comparison with other previous studies. Furthermore, more advanced algorithms and hardware devices should be performed in future for arrhythmia detection and evaluation. PMID:29068369

Instantly Converting Atrial Fibrillation into Sinus Rhythm by a Digital Rectal Exam on a 29-year-Old Male

PubMed Central

Ruan, Cheng-Huai

2010-01-01

Vagal maneuvers cause increase in vagal tone, which has been shown to slow many types supraventricular tachycardia, such as atrial fibrillation (AF). However, the conversion of AF to sinus rhythm is usually not associated with vagal manuvers. Thus, AF is classically treated with medication and electrical cardioversion. Here, we present a 29-year-old male with no cardiovascular history and a low atherosclerotic risk profile who developed AF which converted into sinus rhythm immediately after a digital rectal exam. The patient remained asymptomatic after a 3-month follow-up. This implies that the digital rectal exam can be considered as an additional attempt to convert AF to sinus rhythm in AF patients. PMID:21769254

Atrial Fibrillation Ablation and its Impact on Stroke.

PubMed

Graves, Kevin G; Jacobs, Victoria; May, Heidi T; Cutler, Michael J; Day, John D; Bunch, T Jared

2018-01-24

Atrial fibrillation (AF) is a commonly encountered arrhythmia, which is not yet fully understood. Catheter ablation has shown to be an effective strategy for rhythm management and several small or retrospective studies have shown that stroke rates are decreased in ablated AF patients compared to those medically managed. Several studies even show that ablation returns stroke risk to that of non-AF patients. Large scale, prospective trials will further illuminate this connection and provide mechanistic understanding of the role of the procedure versus the process of selection for the procedure and peri- and post-procedural therapy and management. Furthermore, modification of risk factors associated with AF show a significant increase in the sustained success of AF ablation and can also moderate the progression of AF.

Ventricular fibrillation development following atrial fibrillation after the ingestion of sildenaphil in a patient with Wolff-Parkinson-White syndrome

PubMed Central

Inci, Sinan; Izgu, Ibrahim; Aktas, Halil; Dogan, Pinar; Dogan, Ali

2015-01-01

Summary Complications in the accessory pathway in Wolff-Parkinson-White (WPW) syndrome could cause different clinical conditions by inducing different arrhythmias. Atrial fibrillation (AF) is one of these arrhythmias and is important as it causes life-threatening arrhythmias. It is known that some drugs, underlying cardiac diseases, and the number of accessory pathways, cause a predisposition to this condition. In the current report, we presented a patient with WPW who was admitted to the emergency department with AF, wide QRS and a rapid ventricular response that progressed to ventricular fibrillation. PMID:26361569

Ventricular fibrillation development following atrial fibrillation after the ingestion of sildenaphil in a patient with Wolff-Parkinson-White syndrome.

PubMed

Inci, Sinan; Izgu, Ibrahim; Aktas, Halil; Dogan, Pinar; Dogan, Ali

2015-08-01

Complications in the accessory pathway in Wolff-Parkinson-White (WPW) syndrome could cause different clinical conditions by inducing different arrhythmias. Atrial fibrillation (AF) is one of these arrhythmias and is important as it causes life-threatening arrhythmias. It is known that some drugs, underlying cardiac diseases, and the number of accessory pathways, cause a predisposition to this condition. In the current report, we presented a patient with WPW who was admitted to the emergency department with AF, wide QRS and a rapid ventricular response that progressed to ventricular fibrillation.

Automatic p wave analysis over 24 hours in patients with paroxysmal or persistent atrial fibrillation.

PubMed

Bitzen, Alexander; Sternickel, Karsten; Lewalter, Thorsten; Schwab, Jörg Otto; Yang, Alexander; Schrickel, Jan Wilko; Linhart, Markus; Wolpert, Christian; Jung, Werner; David, Peter; Lüderitz, Berndt; Nickenig, Georg; Lickfett, Lars

2007-10-01

Patients with atrial fibrillation (AF) often exhibit abnormalities of P wave morphology during sinus rhythm. We examined a novel method for automatic P wave analysis in the 24-hour-Holter-ECG of 60 patients with paroxysmal or persistent AF and 12 healthy subjects. Recorded ECG signals were transferred to the analysis program where 5-10 P and R waves were manually marked. A wavelet transform performed a time-frequency decomposition to train neural networks. Afterwards, the detected P waves were described using a Gauss function optimized to fit the individual morphology and providing amplitude and duration at half P wave height. >96% of P waves were detected, 47.4 +/- 20.7% successfully analyzed afterwards. In the patient population, the mean amplitude was 0.073 +/- 0.028 mV (mean variance 0.020 +/- 0.008 mV(2)), the mean duration at half height 23.5 +/- 2.7 ms (mean variance 4.2 +/- 1.6 ms(2)). In the control group, the mean amplitude (0.105 +/- 0.020 ms) was significantly higher (P < 0.0005), the mean variance of duration at half height (2.9 +/- 0.6 ms(2)) significantly lower (P < 0.0085). This method shows promise for identification of triggering factors of AF.

Long-term outcomes following high intensity focused ultrasound ablation for atrial fibrillation.

PubMed

Davies, Edward J; Bazerbashi, Samer; Asopa, Sanjay; Haywood, Guy; Dalrymple-Hay, Malcolm

2014-01-01

The aim of this study is to assess the safety and efficacy of the Epicor high intensity focused ultrasound (St. Jude, Inc.®, Minneapolis, MN, USA) system using seven-day ambulatory electrocardiogram (ECG) monitoring over a two-year follow-up period. One hundred and ten patients undergoing ablation were included from a single center between January 2006 and December 2009. Rhythm was assessed using seven-day ambulatory ECG or permanent pacemaker interrogation. Seventeen patients were lost to follow-up, seven through death. Results were reported according to atrial fibrillation (AF) class preoperatively: paroxysmal, persistent, and long-standing persistent (LSP). Forty-nine percent of patients remained in sinus rhythm at greater than two years. The percentage of patients in sinus rhythm according to preoperative AF class were 81% (paroxysmal AF), 56% (persistent AF), and 18% (long-standing AF). The class of AF prior to surgery, left atrium size, and body mass index determined the long-term outcome. There were no procedure-related complications. We conclude that high intensity focused ultrasound ablation for atrial fibrillation using the Epicor system is safe and effective for surgical patients with paroxysmal AF. The persistent and LSP AF results suggest that alternative ablation strategies should be considered for these patients. © 2013 Wiley Periodicals, Inc.

[Galectin-3 in Patients With Paroxysmal and Persistent Atrial Fibrillation and Metabolic Syndrome].

PubMed

A, V A; Zaslavskaya, E L; Soboleva, A V; Baranova, E I; Listopad, O V; Nifontov, S E; Nrady, A O; Shlyakhto, E V

2016-06-01

To evaluate serum galectin 3 and to determine the potential clinical value of this parameter in patients with atrial fibrillation - AF (paroxysmal and persistent) and metabolic syndrome (MS). We examined 100 patients with MS (50 with paroxysmal or persistent AF and 50 without arrhythmia) and 50 healthy persons. Serum galectin 3 measured by ELISA method, ECHO cardiography was performed to all examined persons. Galectin 3 in patients with MS and AF was higher, than in patients with MS without arrhythmia and much more higher than galectin 3 in healthy persons 0,72 (0,44;1,36), 0,44 (0,42;1,22) and 0,32 (0,28;0,42) ng/ml (<0,01). In patients with persistent AF levels of galectin 3 is higher than in patients with paroxysmal AF. Positive correlation between the levels of galectin 3 and duration arrhythmia was revealed (r=0,301; p<0,01). Higher level of galectin 3 was revealed in patients with frequent paroxysms of AF and ineffective antiarrhythmic therapy. Marker of myocardial fibrosis serum galectin 3 in patients with atrial fibrillation and metabolic syndrome is higher than in patients with the metabolic syndrome, without this arrhythmia and higher than in healthy controls. In patients with persistent AF level of galectin 3 was higher than in patients with paroxysmal AF.

Stability of rotors and focal sources for human atrial fibrillation: focal impulse and rotor mapping (FIRM) of AF sources and fibrillatory conduction.

PubMed

Swarup, Vijay; Baykaner, Tina; Rostamian, Armand; Daubert, James P; Hummel, John; Krummen, David E; Trikha, Rishi; Miller, John M; Tomassoni, Gery F; Narayan, Sanjiv M

2014-12-01

Several groups report electrical rotors or focal sources that sustain atrial fibrillation (AF) after it has been triggered. However, it is difficult to separate stable from unstable activity in prior studies that examined only seconds of AF. We applied phase-based focal impulse and rotor mapping (FIRM) to study the dynamics of rotors/sources in human AF over prolonged periods of time. We prospectively mapped AF in 260 patients (169 persistent, 61 ± 12 years) at 6 centers in the FIRM registry, using baskets with 64 contact electrodes per atrium. AF was phase mapped (RhythmView, Topera, Menlo Park, CA, USA). AF propagation movies were interpreted by each operator to assess the source stability/dynamics over tens of minutes before ablation. Sources were identified in 258 of 260 of patients (99%), for 2.8 ± 1.4 sources/patient (1.8 ± 1.1 in left, 1.1 ± 0.8 in right atria). While AF sources precessed in stable regions, emanating activity including spiral waves varied from collision/fusion (fibrillatory conduction). Each source lay in stable atrial regions for 4,196 ± 6,360 cycles, with no differences between paroxysmal versus persistent AF (4,290 ± 5,847 vs. 4,150 ± 6,604; P = 0.78), or right versus left atrial sources (P = 0.26). Rotors and focal sources for human AF mapped by FIRM over prolonged time periods precess ("wobble") but remain within stable regions for thousands of cycles. Conversely, emanating activity such as spiral waves disorganize and collide with the fibrillatory milieu, explaining difficulties in using activation mapping or signal processing analyses at fixed electrodes to detect AF rotors. These results provide a rationale for targeted ablation at AF sources rather than fibrillatory spiral waves. © 2014 Wiley Periodicals, Inc.

Contact-Free Screening of Atrial Fibrillation by a Smartphone Using Facial Pulsatile Photoplethysmographic Signals.

PubMed

Yan, Bryan P; Lai, William H S; Chan, Christy K Y; Chan, Stephen Chun-Hin; Chan, Lok-Hei; Lam, Ka-Ming; Lau, Ho-Wang; Ng, Chak-Ming; Tai, Lok-Yin; Yip, Kin-Wai; To, Olivia T L; Freedman, Ben; Poh, Yukkee C; Poh, Ming-Zher

2018-04-05

We aimed to evaluate a novel method of atrial fibrillation (AF) screening using an iPhone camera to detect and analyze photoplethysmographic signals from the face without physical contact by extracting subtle beat-to-beat variations of skin color that reflect the cardiac pulsatile signal. Patients admitted to the cardiology ward of the hospital for clinical reasons were recruited. Simultaneous facial and fingertip photoplethysmographic measurements were obtained from 217 hospital inpatients (mean age, 70.3±13.9 years; 71.4% men) facing the front camera and with an index finger covering the back camera of 2 independent iPhones before a 12-lead ECG was recorded. Backdrop and background light intensity was monitored during signal acquisition. Three successive 20-second (total, 60 seconds) recordings were acquired per patient and analyzed for heart rate regularity by Cardiio Rhythm (Cardiio Inc, Cambridge, MA) smartphone application. Pulse irregularity in ≥1 photoplethysmographic readings or 3 uninterpretable photoplethysmographic readings were considered a positive AF screening result. AF was present on 12-lead ECG in 34.6% (n=75/217) patients. The Cardiio Rhythm facial photoplethysmographic application demonstrated high sensitivity (95%; 95% confidence interval, 87%-98%) and specificity (96%; 95% confidence interval, 91%-98%) in discriminating AF from sinus rhythm compared with 12-lead ECG. The positive and negative predictive values were 92% (95% confidence interval, 84%-96%) and 97% (95% confidence interval, 93%-99%), respectively. Detection of a facial photoplethysmographic signal to determine pulse irregularity attributable to AF is feasible. The Cardiio Rhythm smartphone application showed high sensitivity and specificity, with low negative likelihood ratio for AF from facial photoplethysmographic signals. The convenience of a contact-free approach is attractive for community screening and has the potential to be useful for distant AF screening. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Vitamin D status is note related to development of atrial fibrillation in the community

USDA-ARS?s Scientific Manuscript database

Atrial fibrillation (AF) is common and is an important cause of cardiovascular morbidity and mortality. Vitamin D is an emerging risk factor in cardiovascular disease, and vitamin D status is modifiable. Thus, we sought to investigate whether vitamin D status predisposed to the development of AF in ...

Improving Atrial Fibrillation Therapy: Is There a Gene for That?

PubMed Central

Hucker, William J.; Hanley, Alan; Ellinor, Patrick T.

2017-01-01

Atrial fibrillation (AF) is an all-too-common and often challenging reality of clinical care. AF leads to significant morbidity and mortality; however, currently available treatments for AF have modest efficacy and high recurrence rates. In recent years, genetic therapy approaches have been explored in preclinical models of AF, and offer potential as a treatment modality with targeted delivery, tissue specificity, and therapy tailored to address mechanisms underlying the arrhythmia. However, many challenges remain before gene therapy can advance to a clinically relevant AF treatment. In this review, we will summarize the available published data on gene therapy and discuss the challenges, opportunities, and limitations of this approach. PMID:28427583

Variants in ZFHX3 are associated with atrial fibrillation in individuals of European ancestry

PubMed Central

Benjamin, Emelia J.; Rice, Kenneth M.; Arking, Dan E.; Pfeufer, Arne; van Noord, Charlotte; Smith, Albert V.; Schnabel, Renate B.; Bis, Joshua C.; Boerwinkle, Eric; Sinner, Moritz F.; Dehghan, Abbas; Lubitz, Steven A.; D’Agostino, Ralph B.; Lumley, Thomas; Ehret, Georg B.; Heeringa, Jan; Aspelund, Thor; Newton-Cheh, Christopher; Larson, Martin G.; Marciante, Kristin D.; Soliman, Elsayed Z.; Rivadeneira, Fernando; Wang, Thomas J.; Eiriksdottir, Gudny; Levy, Daniel; Psaty, Bruce M.; Li, Man; Chamberlain, Alanna M.; Hofman, Albert; Vasan, Ramachandran S.; Harris, Tamara B.; Rotter, Jerome I.; Kao, W.H. Linda; Agarwal, Sunil K.; Ch. Stricker, Bruno H.; Wang, Ke; Launer, Lenore J.; Smith, Nicholas L.; Chakravarti, Aravinda; Uitterlinden, Andre G.; Wolf, Philip A; Sotoodehnia, Nona; Kottgen, Anna; van Duijn, Cornelia M.; Lunetta, Kathryn L.; Heckbert, Susan R.; Gudnason, Vilmundur; Alonso, Alvaro; Kaab, Stefan; Ellinor, Patrick T.; Witteman, Jacqueline C.

2009-01-01

We conducted meta-analyses of genome-wide association studies (GWAS) for atrial fibrillation (AF) in participants from five community-based cohorts. Meta-analyses of 896 prevalent (15,768 referents) and 2,517 incident (21,337 referents) AF cases identified a novel locus for AF (ZFHX3, rs2106261, risk ratio [RR]=1.19; P=2.3×10−7), an association that was replicated in the German AF Network (odds ratio=1.44; P=1.6×10−11). Combining the discovery and replication results, rs2106261 was significantly associated with AF (RR=1.25; P=1.8×10−15). PMID:19597492

Atrial Fibrillation Burden: Moving Beyond Atrial Fibrillation as a Binary Entity: A Scientific Statement From the American Heart Association.

PubMed

Chen, Lin Y; Chung, Mina K; Allen, Larry A; Ezekowitz, Michael; Furie, Karen L; McCabe, Pamela; Noseworthy, Peter A; Perez, Marco V; Turakhia, Mintu P

2018-05-15

Our understanding of the risk factors and complications of atrial fibrillation (AF) is based mostly on studies that have evaluated AF in a binary fashion (present or absent) and have not investigated AF burden. This scientific statement discusses the published literature and knowledge gaps related to methods of defining and measuring AF burden, the relationship of AF burden to cardiovascular and neurological outcomes, and the effect of lifestyle and risk factor modification on AF burden. Many studies examine outcomes by AF burden classified by AF type (paroxysmal versus nonparoxysmal); however, quantitatively, AF burden can be defined by longest duration, number of AF episodes during a monitoring period, and the proportion of time an individual is in AF during a monitoring period (expressed as a percentage). Current guidelines make identical recommendations for anticoagulation regardless of AF pattern or burden; however, a review of recent evidence suggests that higher AF burden is associated with higher risk of stroke. It is unclear whether the risk increases continuously or whether a threshold exists; if a threshold exists, it has not been defined. Higher burden of AF is also associated with higher prevalence and incidence of heart failure and higher risk of mortality, but not necessarily lower quality of life. A structured and comprehensive risk factor management program targeting risk factors, weight loss, and maintenance of a healthy weight appears to be effective in reducing AF burden. Despite this growing understanding of AF burden, research is needed into validation of definitions and measures of AF burden, determination of the threshold of AF burden that results in an increased risk of stroke that warrants anticoagulation, and discovery of the mechanisms underlying the weak temporal correlations of AF and stroke. Moreover, developments in monitoring technologies will likely change the landscape of long-term AF monitoring and could allow better definition of the significance of changes in AF burden over time. © 2018 American Heart Association, Inc.

Histopathologic analysis of atrial tissue in patients with atrial fibrillation: comparison between patients with atrial septal defect and patients with mitral valvular heart disease.

PubMed

Kwak, Jae Gun; Seo, Jeong-Wook; Oh, Sam Se; Lee, Sang Yun; Ham, Eui Keun; Kim, Woong-Han; Kim, Soo-Jin; Bae, Eun Jung; Lim, Cheoung; Lee, Chang-Ha; Lee, Cheul

2014-01-01

Atrial fibrillation (AF) in adult patients with atrial septal defect (ASD) accompanies an enlarged right atrium (RA) with a less enlarged left atrium (LA), which is the opposite situation in patients with AF and mitral valvular disease. This study was to compare the histopathological change in the atrium of patients with AF of two different etiologies: ASD and mitral disease. Twenty-four patients were enrolled. Group 1 included patients with ASD (8), Group 2 included patients with ASD with AF (6), and Group 3 included patients with mitral disease with AF (10). Preoperative atrial volumes were measured. Atrial tissues were obtained during surgical procedures and stained with periodic acid-Schiff, smooth muscle actin, Sirius red, and Masson's trichrome to detect histopathologic changes compatible with AF. The severity of histopathological changes was represented with "positivity" and "strong positivity" after analyzing digitalized images of the staining. We investigated the relationship between the degree of atrial dilatation and severity of histopathological changes according to the groups and tissues. Group 2 and Group 3 patients showed a tendency toward an enlarged RA volume and enlarged LA volume, respectively, compared with each others. However, in the histopathologic analysis, "positivity" and "strong positivity" showed no significant positive correlations with the degree of atrial volume in special staining. A similar degree of histopathologic changes was observed in both atria in patients with AF (Group 2 and 3) regardless of the degree of dilatation of atrial volume and disease entities. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.

Identification of atrial fibrillation using electrocardiographic RR-interval difference

NASA Astrophysics Data System (ADS)

Eliana, M.; Nuryani, N.

2017-11-01

Automated detection of atrial fibrillation (AF) is an interesting topic. It is an account of very dangerous, not only as a trigger of embolic stroke, but it’s also related to some else chronical disease. In this study, we analyse the presence of AF by determining irregularities of RR-interval. We utilize the interval comparison to measure the degree of irregularities of RR-interval in a defined segment. The series of RR-interval is segmented with the length of 10 of them. In this study, we use interval comparison for the method. We were comparing all of the intervals there each other. Then we put the threshold to define the low difference and high difference (δ). A segment is defined as AF or Normal Sinus by the number of high δ, so we put the tolerance (β) of high δ there. We have used this method to test the 23 patients data from MIT-BIH. Using the approach and the clinical data we find accuracy, sensitivity, and specificity of 84.98%, 91.99%, and 77.85% respectively.

Left atrial electromechanical conduction time predicts atrial fibrillation in patients with mitral stenosis: a 5-year follow-up speckle-tracking echocardiography study.

PubMed

Candan, Ozkan; Gecmen, Cetin; Kalayci, Arzu; Dogan, Cem; Bayam, Emrah; Ozkan, Mehmet

2017-10-01

Prolonged left atrial electromechanical conduction time is related with atrial electrical remodeling, and is predictive of the development of atrial fibrillation. The aim of our study was to examine whether left atrial electromechanical conduction time (EMT) and left atrial strain as measured by speckle tracking echocardiography (STE) are predictors for the development of atrial fibrillation (AF) in patients with mitral stenosis (MS) at 5-year follow-up. A total of 81 patients (61% females; mean age 38.1 ± 12.1 years) with mild or moderate MS of rheumatic origin according to ACC/AHA guidelines who were in sinus rhythm, and were asymptomatic or have NYHA class 1 symptom were included in the study. AF was searched by 12-lead electrocardiograms or 24-h Holter recordings during follow-up period. Atrial electromechanical conduction time (EMT), peak atrial longitudinal strain (PALS) and peak atrial contraction strain (PACS) were measured by STE. EMTs was defined as the interval between the onset of P-wave to the peak late diastolic longitudinal strain in the basal lateral and septal wall. During the follow-up period of 5 years (mean follow-up duration, 48.2 ± 13.3 months), 30 patients (37%) developed AF on standard 12-lead ECG or at their 24-h Holter recording. At follow-up, patients who developed AF were older than patients without AF (42.4 ± 11.3 vs. 35.6 ± 11.9, p = 0.014). Mitral valve area (MVA) (1.39 ± 0.14 vs. 1.48 ± 0.18, p = 0.03), PALS (13.4 ± 4.6 vs. 19 ± 5.2, p < 0.001) and PACS (6 ± 2.7 vs. 8.4 ± 3.8, p = 0.004), were lower in patients who developed AF than in patients who did not develop. However, EMTs-Septal (208.2 ± 28.4 vs. 180.2 ± 38, p = 0.001), and EMTs-Lateral (247.1 ± 27.6 vs. 213.3 ± 43.5, p < 0.001) were longer in patients with AF than in patients without. In multivariate Cox regression analysis, PALS and left atrial EMTs-Lateral were independent predictors for development of AF at follow-up. In patients with mitral stenosis, left atrial strain and electromechanical conduction time in the lateral wall during the long term follow-up period are predictive for the development of atrial fibrillation. Speckle tracking echocardiography is a basic and easily-implemented method based on left atrial parameters which may be helpful for early detection of atrial fibrillation in patients with mitral stenosis.

[Atrial fibrillation before and after pacemaker implantation (WI and DDD) in patients with complete atrioventricular block].

PubMed

Matusik, Paweł; Woznica, Natalia; Lelakowsk, Jacek

2010-05-01

Atrial fibrillation (AF) is a frequent problem of patients with pacemakers, and depends not only on disease but also on stimulation method. The aim of the study was to estimate the prevalence of AF before and after pacemaker implantation as well as to assess the influence of VVI and DDD cardiac pacing on onset of AF in patients with complete atrioventricularblock (AVB). We included 155 patients controlled between 2000 and 2008 in Pacemaker Clinic because of AVB III degree, treated with VVI or DDD pacemaker implantation. Information about the health status of the patients was gathered from medical documentation and analysis of clinical ambulatory electrocardiograms. The study group comprised of 68 women and 87 men, mean age 68.7 +/- 13.9 years during implantation. 69% of patients had VVI pacemaker. There were 72.3% of patients with sinus rhythm before pacemaker implantation. During follow-up 4 +/- 2.8 years in 19.6% cases onset of atrial fibrillation de novo was diagnosed (in 31.3% in VVI mode vs. 2.2% in DDD mode; p = 0.00014). Mean time to AF since implantation was approximately 2.5 years. In VVI group (21 persons) amounted 32.1 months, while in 1 patient with DDD pacemaker 18 months. Between group with AF after implantation and with sinus rhythm preserved there was no statistically significant difference in age or gender (p = 0.89512 and p = 0.1253, respectively). Prevalence of atrial fibrillation after pacemaker implantation increased to 40%. Atrial fibrillation is frequent in patients before and after pacemaker implantation, especially in patients stimulated in VVI mode. Major possibility of atrial fibrillation onset after pacemaker implantation should result in more attention during routine ECG examination.

Recurrence quantification analysis applied to spatiotemporal pattern analysis in high-density mapping of human atrial fibrillation.

PubMed

Zeemering, Stef; Bonizzi, Pietro; Maesen, Bart; Peeters, Ralf; Schotten, Ulrich

2015-01-01

Spatiotemporal complexity of atrial fibrillation (AF) patterns is often quantified by annotated intracardiac contact mapping. We introduce a new approach that applies recurrence plot (RP) construction followed by recurrence quantification analysis (RQA) to epicardial atrial electrograms, recorded with a high-density grid of electrodes. In 32 patients with no history of AF (aAF, n=11), paroxysmal AF (PAF, n=12) and persistent AF (persAF, n=9), RPs were constructed using a phase space electrogram embedding dimension equal to the estimated AF cycle length. Spatial information was incorporated by 1) averaging the recurrence over all electrodes, and 2) by applying principal component analysis (PCA) to the matrix of embedded electrograms and selecting the first principal component as a representation of spatial diversity. Standard RQA parameters were computed on the constructed RPs and correlated to the number of fibrillation waves per AF cycle (NW). Averaged RP RQA parameters showed no correlation with NW. Correlations improved when applying PCA, with maximum correlation achieved between RP threshold and NW (RR1%, r=0.68, p <; 0.001) and RP determinism (DET, r=-0.64, p <; 0.001). All studied RQA parameters based on the PCA RP were able to discriminate between persAF and aAF/PAF (DET persAF 0.40 ± 0.11 vs. 0.59 ± 0.14/0.62 ± 0.16, p <; 0.01). RP construction and RQA combined with PCA provide a quick and reliable tool to visualize dynamical behaviour and to assess the complexity of contact mapping patterns in AF.

Influence of atrial substrate on local capture induced by rapid pacing of atrial fibrillation.

PubMed

Rusu, Alexandru; Jacquemet, Vincent; Vesin, Jean-Marc; Virag, Nathalie

2014-05-01

Preliminary studies showed that the septum area was the only location allowing local capture of both the atria during rapid pacing of atrial fibrillation (AF) from a single site. The present model-based study investigated the influence of atrial substrate on the ability to capture AF when pacing the septum. Three biophysical models of AF with an identical anatomy from human atria but with different AF substrates were used: (i) AF based on multiple wavelets, (ii) AF based on heterogeneities in vagal activation, (iii) AF based on heterogeneities in repolarization. A fourth anatomical model without Bachmann's bundle (BB) was also implemented. Rapid pacing was applied from the septum at pacing cycle lengths in the range of 50-100% of AF cycle length. Local capture was automatically assessed with 24 pairs of electrodes evenly distributed on the atrial surface. The results were averaged over 16 AF simulations. In the homogeneous substrate, AF capture could reach 80% of the atrial surface. Heterogeneities degraded the ability to capture during AF. In the vagal substrate, the capture tended to be more regular and the degradation of the capture was not directly related to the spatial extent of the heterogeneities. In the third substrate, heterogeneities induced wave anchorings and wavebreaks even in areas close to the pacing site, with a more dramatic effect on AF capture. Finally, BB did not significantly affect the ability to capture. Atrial fibrillation substrate had a significant effect on rapid pacing outcomes. The response to therapeutic pacing may therefore be specific to each patient.

The efficacy of intraoperative atrial radiofrequency ablation for atrial fibrillation during concomitant cardiac surgery-the Surgical Atrial Fibrillation Suppression (SAFS) Study.

PubMed

Veasey, Rick A; Segal, Oliver R; Large, Janet K; Lewis, Michael E; Trivedi, Uday H; Cohen, Andrew S; Hyde, Jonathan A J; Sulke, A Neil

2011-10-01

Studies assessing radiofrequency ablation (RFA) for atrial fibrillation (AF) performed at the time of concomitant cardiac surgery have reported high success rates. The efficacy of this treatment has primarily been determined by a single electrocardiogram (ECG) or 24-h Holter monitor at follow-up. We sought to assess the true efficacy of this procedure using prolonged cardiac rhythm monitoring. One hundred patients with paroxysmal (n = 47) and persistent AF (n = 53) requiring cardiac surgery were enrolled. Patients were clinically reviewed 6 weeks post-operatively and were monitored with 7-day Holter with full disclosure, 6 months post-surgery. A cohort of 50 patients also underwent 7 day Holter monitoring preoperatively. AF recurrence was defined as >30 s of AF. At 6 months, 75% of patients were in sinus rhythm according to a single ECG. However, only 62% of patients were free from AF on 7-day Holter; all AF episodes in these patients were asymptomatic. The procedure resulted in a significant decrease in AF burden from 56.2% at baseline to 27.5% at 6 months follow-up, (p < 0.001). Predictors of AF recurrence were (1) pre-operative AF duration; (2) persistent compared with paroxysmal AF; (3) increasing left atrial diameter and (4) requirement for mitral valve surgery. Surgical RFA for the treatment of AF, during concomitant cardiac surgery, is a successful procedure and significantly reduces AF burden. However, 13% of patients have asymptomatic AF episodes only identified with continuous monitoring. This has important implications for post-operative anti-arrhythmic and anticoagulant management and for the definition of surgical AF ablation success.

Morphologies of the atria and pulmonary veins in relation to lone atrial fibrillation progression: a dual-source computed tomography scan study.

PubMed

Liu, Xing-Peng; Xu, Xia; Tian, Ying; Tang, Ri-Bo; Yu, Rong-Hui; Long, De-Yong; Sang, Cai-Hua; Jiang, Chen-Xi; Ning, Man; Dong, Jian-Zeng; Ma, Chang-Sheng

2012-11-01

Atrial Remodeling and Lone Atrial Fibrillation. We sought to investigate the role of anatomic remodeling of the atria and pulmonary veins (PVs) in the progression of lone atrial fibrillation (AF) using dual-source computed tomography (DSCT). From 1,308 consecutive patients referred for an index ablation procedure for AF, we prospectively enrolled 29 consecutive patients with recently developed (<3 months) lone persistent AF (PsAF) and 23 consecutive patients with short-lasting (6-12 months) lone PsAF, all of whom had a history of paroxysmal AF (PAF). The control group consisted of 33 patients with lone PAF. On DSCT, the recently developed PsAF group showed more extensive atrial anatomic remodeling than the PAF group as shown by ∼40% higher spot biatrial volume, even though the mean duration of continuous AF was only 6 weeks. In contrast, the DSCT variables in the recently developed PsAF group and the short-lasting PsAF group were comparable, despite the fact that the mean duration of continuous AF in the latter group was 8 months. Series of cross-sectional areas of the ostial 1.5 cm of PV trunks were comparable in the PAF and PsAF groups in all but 3 ostial planes. A higher spot left atrial volume was the only independent factor associated with the progression of lone PAF to PsAF (OR: 1.06, 95% CI: 1.03-1.09, P<0.0001) on logistic regression. Prominent anatomic remodeling of the atria, rather than the PVs, underlies the mechanism of recent progression of lone paroxysmal AF to the persistent variety. © 2012 Wiley Periodicals, Inc.

Higher risk of death and stroke in patients with persistent vs. paroxysmal atrial fibrillation: results from the ROCKET-AF Trial

PubMed Central

Steinberg, Benjamin A.; Hellkamp, Anne S.; Lokhnygina, Yuliya; Patel, Manesh R.; Breithardt, Günter; Hankey, Graeme J.; Becker, Richard C.; Singer, Daniel E.; Halperin, Jonathan L.; Hacke, Werner; Nessel, Christopher C.; Berkowitz, Scott D.; Mahaffey, Kenneth W.; Fox, Keith A.A.; Califf, Robert M.; Piccini, Jonathan P.

2015-01-01

Aim Anticoagulation prophylaxis for stroke is recommended for at-risk patients with either persistent or paroxysmal atrial fibrillation (AF). We compared outcomes in patients with persistent vs. paroxysmal AF receiving oral anticoagulation. Methods and results Patients randomized in the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared With Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET-AF) trial (n = 14 264) were grouped by baseline AF category: paroxysmal or persistent. Multivariable adjustment was performed to compare thrombo-embolic events, bleeding, and death between groups, in high-risk subgroups, and across treatment assignment (rivaroxaban or warfarin). Of 14 062 patients, 11 548 (82%) had persistent AF and 2514 (18%) had paroxysmal AF. Patients with persistent AF were marginally older (73 vs. 72, P = 0.03), less likely female (39 vs. 45%, P < 0.0001), and more likely to have previously used vitamin K antagonists (64 vs. 56%, P < 0.0001) compared with patients with paroxysmal AF. In patients randomized to warfarin, time in therapeutic range was similar (58 vs. 57%, P = 0.94). Patients with persistent AF had higher adjusted rates of stroke or systemic embolism (2.18 vs. 1.73 events per 100-patient-years, P = 0.048) and all-cause mortality (4.78 vs. 3.52, P = 0.006). Rates of major bleeding were similar (3.55 vs. 3.31, P = 0.77). Rates of stroke or systemic embolism in both types of AF did not differ by treatment assignment (rivaroxaban vs. warfarin, Pinteraction = 0.6). Conclusion In patients with AF at moderate-to-high risk of stroke receiving anticoagulation, those with persistent AF have a higher risk of thrombo-embolic events and worse survival compared with paroxysmal AF. PMID:25209598

Heart-specific overexpression of (pro)renin receptor induces atrial fibrillation in mice.

PubMed

Lian, Hong; Wang, Xiaojian; Wang, Juan; Liu, Ning; Zhang, Li; Lu, Yingdong; Yang, Yanmin; Zhang, Lianfeng

2015-04-01

Atrial fibrillation (AF) is the most common cardiac arrhythmia, causing substantial cardiovascular morbidity and mortality. The renin-angiotensin system (RAS) has been shown to be involved in the pathophysiology of AF. The (pro)renin receptor [(p)RR] is the last identified member of RAS. However, the role of (p)RR in AF is still unknown. Circulating levels of (p)RR were determined using an immunosorbent assay in 22 patients with AF (paroxysmal or persistent) and 22 healthy individuals. The plasma levels of (p)RR increased 3.6-fold in AF patients (P<0.001), indicating a relationship between (p)RR and AF. To investigate the role of (p)RR in the regulation of cardiac arrhythmia, we generated a transgenic mouse with overexpression of human (p)RR gene specifically in the heart. Electrocardiograms from (p)RR transgenic mice showed typical atrial flutter since 2 months, then spontaneously converted to atrial fibrillation by 10 months. The atria of the transgenic mice demonstrated significant dilation and fibrosis, and exhibited a high incidence of sudden death. Additionally, the genes of SERCA and HCN4, which are involved in the electrophysiology of AF, were significantly down-regulated and up-regulated respectively in transgenic mice atria. The phosphorylation of Erk1/2 significantly increased in the atria of the transgenic mice, and the activated Erk1/2 was found predominantly in cardiac fibroblasts, suggesting that the transgenic (p)RR gene may induce atrial fibrillation by activation of Erk1/2 in the cardiac fibroblasts of the atria. (p)RR promotes atrial structural and electrical remodeling in vivo, which indicates that (p)RR plays an important role in the pathological development of AF. Copyright © 2015. Published by Elsevier Ireland Ltd.

Patient Factors Associated with Quality of Life in Atrial Fibrillation Randolph—Determinants of Quality of Life in Atrial Fibrillation

PubMed Central

Randolph, Tiffany C.; Simon, DaJuanicia N.; Thomas, Laine; Allen, Larry A.; Fonarow, Gregg C.; Gersh, Bernard J.; Kowey, Peter R.; Reiffel, James A.; Naccarelli, Gerald V.; Chan, Paul S.; Spertus, John A.; Peterson, Eric D.; Piccini, Jonathan P.

2016-01-01

Background As treatment options for atrial fibrillation (AF) increase, more attention is focused on patients’ experiences and quality of life (QoL). However, little is known about the factors associated with these outcomes. Methods The Atrial Fibrillation Effect on QualiTy-of-life (AFEQT) is a disease-specific QoL tool for AF, with domain and summary scores ranging from 0 (the worst QoL) to 100. Using multivariable linear regression, we evaluated factors associated with baseline AFEQT Summary and Subscale Scores in ORBIT AF, a large, community-based AF registry. Independent associations were reported as coefficient estimates in scores and 95% confidence intervals (CI). Results Overall, AFEQT was assessed in 2,007 AF outpatients from 99 sites. Median age (IQR) was 76 years (67-82) and 43% were female. The median AFEQT summary score was 82 (67-94). Female sex, younger age, new onset AF, higher heart rate, obstructive sleep apnea, symptomatic heart failure (HF), chronic obstructive pulmonary disease and coronary artery disease were all independently associated with reduced QoL. Female sex [Estimate −7.03, 95% CI (−9.31, −4.75)] and new onset versus permanent AF [Estimate −7.44, 95% CI (−11.03, −3.84)] were independently associated with increased symptoms. NYHA Class III or IV HF [Estimate -14.44, 95% CI (−19.46, −8.76)] and female sex [Estimate −7.91, 95% CI (−9.95, −5.88)] were most independently associated with impaired daily activities. Conclusions QoL in patients with AF varies widely and is associated with several patient factors. Understanding patient factors independently associated with worse QoL can be a foundation for tailoring treatment. PMID:27914493

EARLY: a pilot study on early diagnosis of atrial fibrillation in a primary healthcare centre.

PubMed

Benito, Luisa; Coll-Vinent, Blanca; Gómez, Eva; Martí, David; Mitjavila, Joan; Torres, Ferran; Miró, Òscar; Sisó, Antoni; Mont, Lluís

2015-11-01

Atrial fibrillation (AF) is associated with high morbidity and mortality. Early diagnosis is likely to improve therapy and prognosis. The study objective was to evaluate the usefulness of a programme for early diagnosis of AF in patients from an urban primary care centre. Participants were recruited from a randomized sample of patients not diagnosed with AF but having relevant risk factors: age ≥ 65 years, ischaemic and/or valvular heart disease, congestive heart failure, hypertension, and/or diabetes. Patients were randomly assigned to the intervention group (IG) or control group (CG). The intervention included (i) initial visit with clinical history, electrocardiogram, and instruction about pulse palpation and warning signs and (ii) electrocardiogram every 6 months during a 2-year follow-up. The main endpoint of the study was the proportion of new cases diagnosed at 6 months. Secondary endpoints were number of new AF diagnoses and complications associated with the arrhythmia in both groups. A total of 928 patients were included (463 IG and 465 CG). At 6 months, AF was diagnosed in 8 IG patients and 1 CG patient (1.7 vs. 0.2%, respectively, P = 0.018). After 2 years of follow-up, 11 IG patients and 6 CG patients had newly diagnosed AF (2.5 vs. 1.3%, respectively, P = 0.132). Time to first diagnosis of AF was shorter in IG patients [median (inter-quartile range): 7 (192) days vs. 227 (188.5) days in CG, P = 0.029]. The simple screening proposed could be useful for the early detection of AF in primary care. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

Expression and function of Kv1.1 potassium channels in human atria from patients with atrial fibrillation.

PubMed

Glasscock, Edward; Voigt, Niels; McCauley, Mark D; Sun, Qiang; Li, Na; Chiang, David Y; Zhou, Xiao-Bo; Molina, Cristina E; Thomas, Dierk; Schmidt, Constanze; Skapura, Darlene G; Noebels, Jeffrey L; Dobrev, Dobromir; Wehrens, Xander H T

2015-09-01

Voltage-gated Kv1.1 channels encoded by the Kcna1 gene are traditionally regarded as being neural-specific with no known expression or intrinsic functional role in the heart. However, recent studies in mice reveal low-level Kv1.1 expression in heart and cardiac abnormalities associated with Kv1.1-deficiency suggesting that the channel may have a previously unrecognized cardiac role. Therefore, this study tests the hypothesis that Kv1.1 channels are associated with arrhythmogenesis and contribute to intrinsic cardiac function. In intra-atrial burst pacing experiments, Kcna1-null mice exhibited increased susceptibility to atrial fibrillation (AF). The atria of Kcna1-null mice showed minimal Kv1 family ion channel remodeling and fibrosis as measured by qRT-PCR and Masson's trichrome histology, respectively. Using RT-PCR, immunocytochemistry, and immunoblotting, KCNA1 mRNA and protein were detected in isolated mouse cardiomyocytes and human atria for the first time. Patients with chronic AF (cAF) showed no changes in KCNA1 mRNA levels relative to controls; however, they exhibited increases in atrial Kv1.1 protein levels, not seen in paroxysmal AF patients. Patch-clamp recordings of isolated human atrial myocytes revealed significant dendrotoxin-K (DTX-K)-sensitive outward current components that were significantly increased in cAF patients, reflecting a contribution by Kv1.1 channels. The concomitant increases in Kv1.1 protein and DTX-K-sensitive currents in atria of cAF patients suggest that the channel contributes to the pathological mechanisms of persistent AF. These findings provide evidence of an intrinsic cardiac role of Kv1.1 channels and indicate that they may contribute to atrial repolarization and AF susceptibility.

Expression and function of Kv1.1 potassium channels in human atria from patients with atrial fibrillation

PubMed Central

Glasscock, Edward; Voigt, Niels; McCauley, Mark D.; Sun, Qiang; Li, Na; Chiang, David Y.; Zhou, Xiao-Bo; Molina, Cristina E.; Thomas, Dierk; Schmidt, Constanze; Skapura, Darlene G.; Noebels, Jeffrey L.; Dobrev, Dobromir; Wehrens, Xander H. T.

2016-01-01

Voltage-gated Kv1.1 channels encoded by the Kcna1 gene are traditionally regarded as being neural-specific with no known expression or intrinsic functional role in the heart. However, recent studies in mice reveal low-level Kv1.1 expression in heart and cardiac abnormalities associated with Kv1.1-deficiency suggesting that the channel may have a previously unrecognized cardiac role. Therefore, this study tests the hypothesis that Kv1.1 channels are associated with arrhythmogenesis and contribute to intrinsic cardiac function. In intra-atrial burst pacing experiments, Kcna1-null mice exhibited increased susceptibility to atrial fibrillation (AF). The atria of Kcna1-null mice showed minimal Kv1 family ion channel remodeling and fibrosis as measured by qRT-PCR and Masson’s trichrome histology, respectively. Using RT-PCR, immunocytochemistry, and immunoblotting, KCNA1 mRNA and protein were detected in isolated mouse cardiomyocytes and human atria for the first time. Patients with chronic AF (cAF) showed no changes in KCNA1 mRNA levels relative to controls; however, they exhibited increases in atrial Kv1.1 protein levels, not seen in paroxysmal AF patients. Patch-clamp recordings of isolated human atrial myocytes revealed significant dendrotoxin-K (DTX-K)-sensitive outward current components that were significantly increased in cAF patients, reflecting a contribution by Kv1.1 channels. The concomitant increases in Kv1.1 protein and DTX-K-sensitive currents in atria of cAF patients suggest that the channel contributes to the pathological mechanisms of persistent AF. These findings provide evidence of an intrinsic cardiac role of Kv1.1 channels and indicate that they may contribute to atrial repolarization and AF susceptibility. PMID:26162324

Clinical impact of rotor ablation in atrial fibrillation: a systematic review.

PubMed

Parameswaran, Ramanathan; Voskoboinik, Aleksandr; Gorelik, Alexandra; Lee, Geoffrey; Kistler, Peter M; Sanders, Prashanthan; Kalman, Jonathan M

2018-01-11

Rotor mapping and ablation have gained favour over the recent years as an emerging ablation strategy targeting drivers of atrial fibrillation (AF). Their efficacy, however, has been a topic of great debate with variable outcomes across centres. The aim of this study was to systematically review the recent medical literature to determine the medium-term outcomes of rotor ablation in patients with paroxysmal atrial fibrillation (PAF) and persistent atrial fibrillation (PeAF). A systematic search of the contemporary scientific literature (PubMed and EMBASE) was performed in August 2017. Only studies assessing arrhythmia-free survival from rotor ablation of AF were included. We used the random-effects model to assess the primary outcome of pooled medium-term single-procedure AF-free survival for both PAF and PeAF. Success rates from multiple procedures and complication rates were also examined. We included 11 observational studies (4 PAF and 10 PeAF) with a total of 556 patients (166 PAF and 390 PeAF). Pooled single-procedure freedom from AF was 37.8% [95% confidence interval 5.6-86.3%] at a mean follow-up period of 13.8 ± 1.8 months for PAF and 59.2% (95% CI 41.4-74.9%) at a mean follow-up period of 12.9 ± 6 months for PeAF. There was a marked heterogeneity between studies (I2 = 93.8% for PAF and 88.3% for PeAF). The mean complication rate of rotor ablation among the reported studies was 3.4%. The wide variability in success rate between different centres performing rotor ablations suggests that the optimal ablation strategy, particularly targeting rotors, is unclear. Results from randomized studies are necessary before this technique can be considered as an established clinical tool. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2018. For permissions, please email: journals.permissions@oup.com.

Fragmented QRS may predict new onset atrial fibrillation in patients with ST-segment elevation myocardial infarction.

PubMed

Yesin, Mahmut; Kalçık, Macit; Çağdaş, Metin; Karabağ, Yavuz; Rencüzoğulları, İbrahim; Gürsoy, Mustafa Ozan; Efe, Süleyman Çağan; Karakoyun, Süleyman

Fragmented QRS (fQRS) has been shown to be a marker of local myocardial conduction abnormalities, cardiac fibrosis in previous studies. It was also reported to be a predictor of sudden cardiac death and increased morbidity and mortality in selected populations. However, there is no study investigating the role of fQRS in the development of atrial fibrillation in patients with ST segment elevation myocardial infarction (STEMI). In this study we aimed to investigate the relationship between the presence of fQRS after primary percutaneous coronary intervention (pPCI) and in-hospital development of new-onset atrial fibrilation (AF) in patients with STEMI. This study enrolled 171 patients undergoing pPCI for STEMI. Among these patients 24 patients developed AF and the remaining 147 patients were designated as the controls. All clinical, demographical and laboratory parameters were entered into a dataset and compared between AF group and the controls. The presence of fQRS was higher in the AF group than in the controls (P=0.001). Diabetes mellitus and fQRS was significantly more common in the AF group (P=0.003 and P=0.001 respectively) Logistic regression analysis demonstrated that the presence of fQRS was the independent determinant of AF (OR: 3.243, 95% CI 1.016-10.251, P=0.042). Increased atrial fibrillation was observed more frequently in STEMI patients with fQRS than in patients without fQRS. fQRS is an important determinant of AF in STEMI after pPCI. Copyright © 2017 Elsevier Inc. All rights reserved.

Magnitude of increase in QTc interval after initiation of dofetilide in patients with persistent atrial fibrillation is associated with increased rates of pharmacological cardioversion and long-term freedom from recurrent atrial fibrillation.

PubMed

Huang, Henry D; Waks, Jonathan W; Steinhaus, Daniel A; Zimetbaum, Peter

2016-07-01

Dofetilide is a class III antiarrhythmic drug approved for the treatment of atrial fibrillation (AF). Dofetilide-induced corrected QT (QTc) interval prolongation is a surrogate for the degree of drug effect, but the relationships between drug-induced QTc interval prolongation, pharmacological cardioversion (PCV), and freedom from recurrent AF are unclear. The purpose of this study was to assess associations between QTc interval change during dofetilide initiation and PCV and long-term AF recurrence. We performed retrospective analyses of a prospective cohort of patients with AF admitted for dofetilide initiation between 2001 and 2014. Clinical characteristics and electrocardiographic variables were assessed. We evaluated outcomes of successful PCV in patients with persistent AF and time to recurrence of AF in patients with paroxysmal and persistent AF. During the study, 243 patients with persistent AF and 176 patients with paroxysmal AF initiated dofetilide. PCV occurred in 93/243 (41.7%) patients with persistent AF. After multivariable adjustment, QTc interval change was associated with PCV (adjusted odds ratio 1.21; P = .003 per 10-ms QTc increase). Inhospital QTc interval change was associated with long-term freedom from AF in patients with persistent AF (adjusted hazard ratio 0.92; P = .011 at 4 years per 10-ms QTc increase), but not in patients with paroxysmal AF. In patients with persistent AF, PCV was also associated with long-term freedom from recurrent AF (adjusted hazard ratio 0.62; P = .009 at 4 years). The magnitude of QTc interval prolongation during dofetilide initiation is an independent predictor of successful PCV and long-term freedom from arrhythmia in patients with persistent AF. QTc interval change had no association with AF recurrence in patients with paroxysmal AF, suggesting that different mechanisms of arrhythmogenesis may be operant in different AF types. Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Time of Occurrence and Duration of Atrial Fibrillation Following Coronary Artery Bypass Grafting.

PubMed

Avdic, Sevleta; Osmanovic, Enes; Kadric, Nedzad; Mujanovic, Emir; Ibisevic, Merima; Avdic, Azra

2016-04-01

Dilatation of the left atrium and left ventricular diastolic dysfunction (DDLV) according to recent studies has significance in the occurrence of postoperative atrial fibrillation (AF), stroke and death. Authors of some studies found no relationship between these parameters and atrial fibrillation. this study is to determine the time of occurrence and duration of atrial fibrillation in patients after surgical revascularization (CABG) due to the presence of left ventricular diastolic dysfunction and left atrium dilatation and identify the most significant predictors of incident AF. Prospective study included 116 patients undergoing surgical myocardial revascularization followed from admission to discharge. The study was conducted at the Special Hospital "Heart Center BH" Tuzla for a period of one year (March 2011/2012 g.). For all patients was performed preoperative ultrasound examination, especially parameters of diastolic function of the left ventricle and left atrium volume index (LAVi), as the best parameter sized left atrium, and the postoperative occurrence of certain AF and day occurrence, duration in hours, the number of attacks. To assess whether an event occurred or not was used logistic regression, and the effect of time on the event of interest is analyzed by Cox 's regression hazard parallel. 75.9 % of patients had DDLV, and 91.4 % were hypertensives, 12.9 % from the previous stroke (ICV) and 42.2 % diabetics (DM), 14 % with COPD. The average age of patients was 61.41 ± 4.69 years. In both groups was 32.8 % women and 67.2 % men. LAVi preoperative values were significantly higher as DDLV greater degree. In patients with DDLV and higher values LAVi risk of AF is higher, the greater the length of AF and significantly higher number of attacks FA. Early occurrence of atrial fibrillation and its longer duration in function with increasing LAVi a marked increase in the value LAVi have the greatest hazard for the early appearance of atrial fibrillation. As a result of analysis of the most significant predictors of AF are DDLV and LAVi. Postoperative atrial fibrillation occurs earlier and lasts longer in patients with DDLV and elevated left atrial volume index especially LAV > 36ml/m(2). LAVi has the best explanation of the function of hazard occurrence of atrial fibrillation after CABG.

Increased susceptibility to atrial fibrillation secondary to atrial fibrosis in transgenic goats expressing transforming growth factor - B1

USDA-ARS?s Scientific Manuscript database

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in people with significant morbidity and mortality. There is a strong association between atrial fibrosis and AF. Transforming growth factor B1 (TGF-B1) is an essential mediator of atrial fibrosis in animal models and human pat...

Dynamics of Endo- and Epicardial Focal Fibrillation Waves at the Right Atrium in a Patient With Advanced Atrial Remodelling.

PubMed

van der Does, Lisette J M E; Kik, Charles; Bogers, Ad J J C; Allessie, Maurits A; de Groot, Natasja M S

2016-10-01

Focal waves appear frequently at the epicardium during persistent atrial fibrillation (AF), however, the origin of these waves is under debate. We performed simultaneous endo-epicardial mapping of the right atrial wall during longstanding persistent AF in a patient undergoing cardiac surgery. During 10 seconds 53 and 59 focal waves appeared at random at respectively the endocardium and epicardium. Repetitive focal activity did not last longer than 3 cycles. Transmural asynchrony and conduction might be the origin of focal waves. Asynchronous propagation of fibrillation waves in 3 dimensions would stabilize the arrhythmia and could explain the limited success of persistent AF ablation. Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Renal dysfunction as a predictor of stroke and systemic embolism in patients with nonvalvular atrial fibrillation: validation of the R(2)CHADS(2) index in the ROCKET AF (Rivaroxaban Once-daily, oral, direct factor Xa inhibition Compared with vitamin K antagonism for prevention of stroke and Embolism Trial in Atrial Fibrillation) and ATRIA (AnTicoagulation and Risk factors In Atrial fibrillation) study cohorts.

PubMed

Piccini, Jonathan P; Stevens, Susanna R; Chang, YuChiao; Singer, Daniel E; Lokhnygina, Yuliya; Go, Alan S; Patel, Manesh R; Mahaffey, Kenneth W; Halperin, Jonathan L; Breithardt, Günter; Hankey, Graeme J; Hacke, Werner; Becker, Richard C; Nessel, Christopher C; Fox, Keith A A; Califf, Robert M

2013-01-15

We sought to define the factors associated with the occurrence of stroke and systemic embolism in a large, international atrial fibrillation (AF) trial. In ROCKET AF (Rivaroxaban Once-daily, oral, direct factor Xa inhibition Compared with vitamin K antagonism for prevention of stroke and Embolism Trial in Atrial Fibrillation), 14 264 patients with nonvalvular AF and creatinine clearance ≥30 mL/min were randomized to rivaroxaban or dose-adjusted warfarin. Cox proportional hazards modeling was used to identify factors at randomization independently associated with the occurrence of stroke or non-central nervous system embolism based on intention-to-treat analysis. A risk score was developed in ROCKET AF and validated in ATRIA (AnTicoagulation and Risk factors In Atrial fibrillation), an independent AF patient cohort. Over a median follow-up of 1.94 years, 575 patients (4.0%) experienced primary end-point events. Reduced creatinine clearance was a strong, independent predictor of stroke and systemic embolism, second only to prior stroke or transient ischemic attack. Additional factors associated with stroke and systemic embolism included elevated diastolic blood pressure and heart rate, as well as vascular disease of the heart and limbs (C-index 0.635). A model that included creatinine clearance (R(2)CHADS(2)) improved net reclassification index by 6.2% compared with CHA(2)DS(2)VASc (C statistic=0.578) and by 8.2% compared with CHADS(2) (C statistic=0.575). The inclusion of creatinine clearance <60 mL/min and prior stroke or transient ischemic attack in a model with no other covariates led to a C statistic of 0.590.Validation of R(2)CHADS(2) in an external, separate population improved net reclassification index by 17.4% (95% confidence interval, 12.1%-22.5%) relative to CHADS(2). In patients with nonvalvular AF at moderate to high risk of stroke, impaired renal function is a potent predictor of stroke and systemic embolism. Stroke risk stratification in patients with AF should include renal function. URL: http://www.ClinicalTrials.gov. Unique identifier: NCT00403767.

Surgical treatment of atrial fibrillation: a review.

PubMed

Hiari, Nadine

2011-01-01

Atrial fibrillation is the most commonly sustained arrhythmia in man. While it affects millions of patients worldwide, its incidence will markedly increase with an aging population. Primary goals of AF therapy are to (1) reduce embolic complications, particularly stroke, (2) alleviate symptoms, and (3) prevent long-term heart remodelling. These have been proven to be a challenge as there are major limitations in our knowledge of the pathological and electrophysiological mechanisms underlying AF. Although advances continue to be made in the medical management of this condition, pharmacotherapy is often unsuccessful. Because of the high recurrence rate of AF despite antiarrhythmic drug therapy for maintenance of sinus rhythm and the adverse effects of these drugs, there has been growing interest in nonpharmacological strategies. Surgery for treatment of AF has been around for some time. The Cox-Maze procedure is the gold standard for the surgical treatment of atrial fibrillation and has more than 90% success in eliminating atrial fibrillation. Although the cut and sew maze is very effective, it has been superseded by newer operations that rely on alternate energy sources to create lines of conduction block. In addition, the evolution of improved ablation technology and instrumentation has facilitated the development of minimally invasive approaches. In this paper, the rationale for surgical ablation for atrial fibrillation and the different surgical techniques that were developed will be explored. In addition, it will detail the new approaches to surgical ablation of atrial fibrillation that employ alternate energy sources.

Incidence of atrial fibrillation in whites and African-Americans: the Atherosclerosis Risk in Communities (ARIC) study.

PubMed

Alonso, Alvaro; Agarwal, Sunil K; Soliman, Elsayed Z; Ambrose, Marietta; Chamberlain, Alanna M; Prineas, Ronald J; Folsom, Aaron R

2009-07-01

To define the incidence and cumulative risk of atrial fibrillation (AF) in a population-based cohort of whites and African Americans. African-Americans reportedly have a lower risk of AF than whites despite their higher exposure to AF risk factors. However, precise estimates of AF incidence in African Americans have not been previously published. We studied the incidence of AF in the Atherosclerosis Risk in Communities (ARIC) study, which has followed up 15,792 men and women 45 to 65 years of age at baseline from 4 communities in the United States since 1987. Atrial fibrillation cases were identified from electrocardiograms conducted at baseline and 3 follow-up visits, and from hospitalizations and death certificates through the end of 2004. During follow-up, 1,085 new cases of AF were identified (196 in African Americans, 889 in whites). Crude incidence rates of AF were 6.7, 4.0, 3.9, and 3.0 per 1,000 persons per year in white men, white women, African-American men, and African-American women, respectively. Increasing age was exponentially associated with an elevated risk of AF. Compared to whites, African-Americans had a 41% (95% CI: 8%-62%) lower age- and sex-adjusted risk of being diagnosed with AF. The cumulative risk of AF at 80 years of age was 21% in white men, 17% in white women, and 11% in African-American men and women. In this population-based cohort, African Americans presented a lower risk of AF than whites. Still, the burden of AF among the former is substantial, with 1 in 9 receiving a diagnosis of AF before 80 years of age.

Vitamin D and new-onset atrial fibrillation: A meta-analysis of randomized controlled trials.

PubMed

Huang, Wei-Ling; Yang, Jun; Yang, Jian; Wang, Hui-Bo; Yang, Chao-Jun; Yang, Ying

2017-11-14

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, which affects 1.5% to 2% of the general population. More than six million Europeans suffer from AF. To research vitamin D levels in the prevention of new-onset atrial fibrillation (AF), we conducted a systematic review of randomized controlled trials (RCTs). We focused on the vitamin D levels in the prevention of new-onset AF. The outcomes assessed were vitamin D levels, left ventricular ejection fraction (LVEF), and left atrium diameter. Six RCTs ultimately met the inclusion criteria in the meta-analysis. The outcomes of Vitamin D levels (MD = -4.27, 95% CI = -5.20 to-3.34, P = 0.30) in the new-onset AF showed no significant difference. The left atrium diameter (MD = 1.96, 95% CI = 1.48 to 2.60, P < 0.01) between new-onset AF and LVEF (MD = -0.92, 95% CI = -1.59 to -0.26, P < 0.01) showed significant difference. Our study shows that circulating vitamin D levels may not play a major role in the development of new-onset AF. Copyright © 2017 Hellenic Society of Cardiology. Published by Elsevier B.V. All rights reserved.

Imaging Mass Spectrometry for Characterization of Atrial Fibrillation Subtypes.

PubMed

Klein, Oliver; Hanke, Thorsten; Nerbrich, Grit; Yan, Junfeng; Schubert, Benedikt; Giavalisco, Patrick; Noack, Frank; Thiele, Herbert; Mohamed, Salah A

2018-05-13

Atrial fibrillation (AF) is a cardiac arrhythmia characterized by a rapid and irregular heart rhythm. AF types, paroxysmal (PX), persistent (PE) and long-lasting persistent (LSP), requires differences in clinical management. Unfortunately, a significant proportion of AF patients are clinical misclassified. Therefore, our study aim that MALDI-Imaging (IMS) is valuable as a diagnostic aid in AF subtypes assessment. Patients were clinically classified according guidelines of the European Society of Cardiology. FFPE tissue specimens from PE, PX and LSP subtype were analysed by MALDI-IMS and evaluated by multi-statistical testing. Proteins were subsequent identified using LC-MS/MS and findings were confirmed by immunohistochemistry and through the determination of potential fibrosis via histopathology RESULT: : Determined characteristic peptide signatures and peptide values facilitate to distinguish between PE, PE and LSP arterial fibrillation subtypes. In particular, peptide values from alpha 1 type I collagen were identified that were significantly higher in LSP and PE tissue but not in PX myocardial AF tissue. These findings were confirmed by immunohistochemistry and through the determination of potential fibrosis via histopathology. Our results represent an improvement in AF risk stratification by using MALDI-IMS as a promising approach for AF tissue assessment. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Atrial Fibrillation: Epidemiology and Peculiarities in the Elderly.

PubMed

da Silva, Rose Mary Ferreira Lisboa

2015-01-01

The prevalence of atrial fibrillation (AF) increases with age and two-thirds of patients with AF aged over 75 years. In addition, comorbidities are frequent in the elderly and worsen the prognosis. There are poorer quality of life, increased number of hospitalizations and cardiovascular events. The annual death rate was 8% in patients older than 75 years, and higher among women. There is a significant association between AF and cognitive disorders. Despite highest stroke risk, elderly have been paradoxically less likely to receive oral anticoagulation. This review summarizes available data on the epidemiology, risk factors, and scores of bleeding and systemic embolism, evolution and the approach of elderly patients with AF.

Association of Atrial Fibrillation with Morphological and Electrophysiological Changes of the Atrial Myocardium.

PubMed

Matějková, Adéla; Šteiner, Ivo

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. For long time it was considered as pure functional disorder, but in recent years, there were identified atrial locations, which are involved in the initiation and maintenance of this arrhythmia. These structural changes, so called remodelation, start at electric level and later they affect contractility and morphology. In this study we attempted to find a possible relation between morphological (scarring, amyloidosis, left atrial (LA) enlargement) and electrophysiological (ECG features) changes in patients with AF. We examined grossly and histologically 100 hearts of necropsy patients - 54 with a history of AF and 46 without AF. Premortem ECGs were evaluated. The patients with AF had significantly heavier heart, larger LA, more severely scarred myocardium of the LA and atrial septum, and more severe amyloidosis in both atria. Severity of amyloidosis was higher in LAs vs. right atria (RAs). Distribution of both fibrosis and amyloidosis was irregular. The most affected area was in the LA anterior wall. Patients with a history of AF and with most severe amyloidosis have more often abnormally long P waves. Finding of long P wave may contribute to diagnosis of a hitherto undisclosed atrial fibrillation.

Intermittent atrial tachycardia promotes repolarization alternans and conduction slowing during rapid rates, and increases susceptibility to atrial fibrillation in a free-behaving sheep model.

PubMed

Monigatti-Tenkorang, Joanna; Jousset, Florian; Pascale, Patrizio; Vesin, Jean-Marc; Ruchat, Patrick; Fromer, Martin; Narayan, Sanjiv M; Pruvot, Etienne

2014-04-01

Paroxysmal atrial fibrillation (AF) may be triggered by intermittent atrial tachycardia, and ultimately lead to persistent AF. However, the mechanisms by which intermittent atrial tachycardia promotes sustained AF are not well understood. Eight sheep were chronically implanted with 2 pacemakers for the recording of broadband right atrial unipolar electrograms, and for the delivery of electrophysiological stimulation protocols and intermittent right atrial tachycardia. Right atrial kinetics of activation recovery interval (ARI) as a surrogate for action potential duration, of conduction time and velocity, and of repolarization alternans were analyzed at incremental pacing rates during the remodeling process induced by weeks of intermittent atrial tachycardia until the development of sustained AF. Intermittent atrial tachycardia decreased ARI and blunted its rate adaptation, facilitated atrial capture, and slowed conduction at high rates, and increased susceptibility to pacing-induced AF. In spite of blunted ARI rate adaptation, right atrial repolarization alternans was maintained during remodeling, and further increased in magnitude just before rapid pacing-induced AF. This study suggests that weeks of intermittent right atrial tachycardia result in a gradual electrical remodeling favorable for wavebreaks and reentry that may facilitate fibrillation. © 2014 Wiley Periodicals, Inc.

Lone atrial fibrillation: what is known and what is to come.

PubMed

Potpara, T S; Lip, G Y H

2011-04-01

Atrial fibrillation (AF) is the most prevalent sustained cardiac arrhythmia in adults, affecting >1% of general population. Atrial fibrillation is commonly associated with structural heart disease and is a major cause of significant cardiovascular morbidity and mortality. AF sometimes develops in a subset of young patients (e.g. aged ≤60 years), with no evidence of associated cardiopulmonary or other comorbid disease (including hypertension), and has been referred to as 'lone AF'. The latter generally has a favourable prognosis; the prognostic and therapeutic implications of an accurate identification of patients with truly lone AF (that is, truly at low risk of complications), if any, would be of the utmost importance. The true prevalence of lone AF is unknown, varying between 1.6% and 30%, depending on the particular study population. Nonetheless, novel risk factors for AF, including obesity, metabolic syndrome, sleep apnea, alcohol consumption, endurance sports, anger, hostility, subclinical atherosclerosis and others, have been increasingly recognised. Also, various underlying pathophysiological mechanisms predisposing to AF, including increased atrial stretch, structural and electrophysiological alterations, autonomic imbalance, systemic inflammation, oxidative stress and genetic predisposition, have been proposed. The growing evidence of these diverse (and numerous) pathogenic mechanisms and factors related to AF inevitably raises the question of whether 'lone AF' does exist at all. In this review article, we summarise the current knowledge of the epidemiology, pathophysiology, clinical course and treatment of patients with so-called 'lone AF' and outline emerging insights into its pathogenesis and the potential therapeutic implications of a diagnosis of lone AF. © 2011 Blackwell Publishing Ltd.

Fast atrial fibrillation and caecal volvulus – a case report and evidence based management

PubMed Central

Liu, Alexander; Nicol, Edward

2011-01-01

An 81-year-old Caucasian lady with permanent atrial fibrillation (AF) was admitted with palpitations and fast AF. She took bisoprolol and warfarin with subtherapeutic international normalised ratio. Rate control of AF was successful. Around 36 h later, she developed abdominal pain and vomiting. A caecal volvulus was diagnosed on CT. She underwent emergency laparotomy. Intraoperatively, an obstructing tumour was found in the colonic hepatic flexure. It was deemed inoperable. The caecal volvulus was decompressed and an ileo-transverse colon bypass was performed. She made a good recovery and her fast AF settled postoperatively. She was seen by the oncology team and was discharged with palliative care support with no further exacerbation of AF. PMID:22669994

Improving Atrial Fibrillation Therapy: Is There a Gene for That?

PubMed

Hucker, William J; Hanley, Alan; Ellinor, Patrick T

2017-04-25

Atrial fibrillation (AF) is an all-too-common and often challenging reality of clinical care. AF leads to significant morbidity and mortality; however, currently available treatments for AF have modest efficacy and high recurrence rates. In recent years, genetic therapy approaches have been explored in preclinical models of AF, and offer potential as a treatment modality with targeted delivery, tissue specificity, and therapy tailored to address mechanisms underlying the arrhythmia. However, many challenges remain before gene therapy can advance to a clinically relevant AF treatment. In this review, we summarize the available published data on gene therapy and discuss the challenges, opportunities, and limitations of this approach. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Perspectives and challenges of antioxidant therapy for atrial fibrillation.

PubMed

Gasparova, Iveta; Kubatka, Peter; Opatrilova, Radka; Caprnda, Martin; Filipova, Slavomira; Rodrigo, Luis; Malan, Leone; Mozos, Ioana; Rabajdova, Miroslava; Nosal, Vladimir; Kobyliak, Nazarii; Valentova, Vanda; Petrovic, Daniel; Adamek, Mariusz; Kruzliak, Peter

2017-01-01

Atrial fibrillation (AF) is the most common sustained arrhythmia associated with significant morbidity and mortality. The mechanisms underlying the pathogenesis of AF are poorly understood, although electrophysiological remodeling has been described as an important initiating step. There is growing evidence that oxidative stress is involved in the pathogenesis of AF. Many known triggers of oxidative stress, such as age, diabetes, smoking, and inflammation, are linked with an increased risk of arrhythmia. Numerous preclinical studies and clinical trials reported the importance of antioxidant therapy in the prevention of AF, using vitamins C and E, polyunsaturated fatty acids, statins, or nitric oxide donors. The aim of our work is to give a current overview and analysis of opportunities, challenges, and benefits of antioxidant therapy in AF.

Atrial fibrillation in the elderly: physicians' attitudes to anticoagulation.

PubMed

King, D; Davies, K N; Slee, A; Silas, J H

1995-01-01

The use of warfarin and aspirin for the primary prevention of stroke in elderly patients with atrial fibrillation (AF) is controversial. To establish current practice we circulated a questionnaire to 300 geriatricians (G) and 300 cardiologists (C). The response rates were 47% G and 51% C. Most physicians prescribed warfarin in AF associated with mitral stenosis (G vs C, 86% vs 89%, NS). Cardiologists were more likely to prescribe warfarin in AF associated with dilated cardiomyopathy (G vs C, 52% vs 86%, P < 0.01). A minority would prescribe warfarin in aortic valve disease and AF (G vs C, 37% vs 24%, P < 0.05) and lone AF (G vs C, 10% vs 26%, P < 0.01). Aspirin was favoured in aortic valve disease and lone AF. The cardiologists were less reluctant to use warfarin in the young and more likely to electrically cardiovert the young with chronic AF.

Hypertension and atrial fibrillation: epidemiology, pathophysiology and therapeutic implications.

PubMed

Lau, Y-F; Yiu, K-H; Siu, C-W; Tse, H-F

2012-10-01

Hypertension is one of the most important risk factors associated with atrial fibrillation (AF) and increased the risk of cardiovascular events in patients with AF. However, the pathophysiological link between hypertension and AF is unclear. Nevertheless, this can be explained by the hemodynamic changes of the left atrium secondary to long standing hypertension, resulting in elevated left atrium pressure and subsequently left atrial enlargement. Moreover, the activation of renin-angiotensin-aldosterone system (RAAS) activation in patients with hypertension induces left atrial fibrosis and conduction block in the left atrium, resulting in the development of AF. Accordingly, recent studies have shown that effective blockage of RAAS by angiotensin converting enzyme inhibitors or angiotensin receptor antagonist may be effective in both primary and secondary prevention of AF in patients with hypertension, although with controversies. In addition, optimal antithrombotic therapy, blood pressure control as well as rate control for AF are key to the management of patients with AF.

Left Atrial Appendage Closure in Atrial Fibrillation: A World without Anticoagulation?

PubMed Central

Contractor, Tahmeed; Khasnis, Atul

2011-01-01

Atrial Fibrillation (AF) is a common arrhythmia with an incidence that is as high as 10% in the elderly population. Given the large proportion of strokes caused by AF as well as the associated morbidity and mortality, reducing stroke burden is the most important part of AF management. While warfarin significantly reduces the risk of AF-related stroke, perceived bleeding risks and compliance limit its widespread use in the high-risk AF population. The left atrial appendage is believed to be the “culprit” for thrombogenesis in nonvalvular AF and is a new therapeutic target for stroke prevention. The purpose of this review is to explore the evolving field of percutaneous LAA occlusion. After briefly highlighting the risk of stroke with AF, problems with warfarin, and the role of the LAA in clot formation, this article discusses the feasibility and efficacy of various devices which have been developed for percutaneous LAA occlusion. PMID:21559225

2016 Guidelines of the Taiwan Heart Rhythm Society and the Taiwan Society of Cardiology for the management of atrial fibrillation.

PubMed

Chiang, Chern-En; Wu, Tsu-Juey; Ueng, Kwo-Chang; Chao, Tze-Fan; Chang, Kuan-Cheng; Wang, Chun-Chieh; Lin, Yenn-Jiang; Yin, Wei-Hsian; Kuo, Jen-Yuan; Lin, Wei-Shiang; Tsai, Chia-Ti; Liu, Yen-Bin; Lee, Kun-Tai; Lin, Li-Jen; Lin, Lian-Yu; Wang, Kang-Ling; Chen, Yi-Jen; Chen, Mien-Cheng; Cheng, Chen-Chuan; Wen, Ming-Shien; Chen, Wen-Jone; Chen, Jyh-Hong; Lai, Wen-Ter; Chiou, Chuen-Wang; Lin, Jiunn-Lee; Yeh, San-Jou; Chen, Shih-Ann

2016-11-01

Atrial fibrillation (AF) is the most common sustained arrhythmia. Both the incidence and prevalence of AF are increasing, and the burden of AF is becoming huge. Many innovative advances have emerged in the past decade for the diagnosis and management of AF, including a new scoring system for the prediction of stroke and bleeding events, the introduction of non-vitamin K antagonist oral anticoagulants and their special benefits in Asians, new rhythm- and rate-control concepts, optimal endpoints of rate control, upstream therapy, life-style modification to prevent AF recurrence, and new ablation techniques. The Taiwan Heart Rhythm Society and the Taiwan Society of Cardiology aimed to update the information and have appointed a jointed writing committee for new AF guidelines. The writing committee members comprehensively reviewed and summarized the literature, and completed the 2016 Guidelines of the Taiwan Heart Rhythm Society and the Taiwan Society of Cardiology for the Management of Atrial Fibrillation. This guideline presents the details of the updated recommendations, along with their background and rationale, focusing on data unique for Asians. The guidelines are not mandatory, and members of the writing committee fully realize that treatment of AF should be individualized. The physician's decision remains most important in AF management. Copyright © 2016. Published by Elsevier B.V.

Persistent Atrial Fibrillation Ablation in Females: Insight from the MAGIC-AF Trial.

PubMed

Singh, Sheldon M; D'Avila, Andre; Aryana, Arash; Kim, Young-Hoon; Mangrum, J Michael; Michaud, Gregory F; Dukkipati, Srinivas R; Heist, E Kevin; Barrett, Conor D; Thorpe, Kevin E; Reddy, Vivek Y

2016-07-27

Atrial fibrillation (AF) ablation is less frequently performed in women when compared to men. There are conflicting data on the safety and efficacy of AF ablation in women. The objective of this study was to compare the clinical characteristics and outcomes in a contemporary cohort of men and women undergoing persistent AF ablation procedures. A total of 182 men and 53 women undergoing a first-ever persistent AF catheter ablation procedure in The Modified Ablation Guided by Ibutilide Use in Chronic Atrial Fibrillation (MAGIC-AF) trial were evaluated. Clinical and procedural characteristics were compared between each gender. The primary efficacy endpoint was the 1-year single procedure freedom from atrial arrhythmia off anti-arrhythmic drugs. Women undergoing catheter ablation procedures were older than men (P < 0.001). The duration of AF and associated co-morbidities were similar between both genders. Single procedure drug-free atrial arrhythmia recurrence occurred in 53% of the cohort with no difference based on gender (men = 54%, women = 53%; P = 1.0). Procedural (P = 0.04), fluoroscopic (P = 0.02), and ablation times (P = 0.003) were shorter in women compared to men. Periprocedural complications and postablation improvement in quality of life were similar between men and women. Women undergoing a first-ever persistent AF ablation procedure were older but had similar clinical outcomes and complications when compared with men. © 2016 Wiley Periodicals, Inc.

Stroke event rates in anticoagulated patients with paroxysmal atrial fibrillation.

PubMed

Lip, G Y H; Frison, L; Grind, M

2008-07-01

To test the hypothesis that stroke and systemic embolic events (SEE) in the stroke prevention using an oral thrombin inhibitor in atrial fibrillation (SPORTIF) III and V trials are different between paroxysmal and persistent atrial fibrillation (AF). Data analysis from two cohorts of patients enrolled in the prospective SPORTIF III and V clinical trials (n = 7329); 836 subjects (11.4%) with paroxysmal AF [mean age 70.1 years (SD = 9.5)] were compared with 6493 subjects with persistent AF for this ancillary study. The annual event rates for stroke/SEE are 1.73% for persistent AF and 0.93% for paroxysmal AF. In a multivariate analysis, after adjusting for stroke risk factors, gender and aspirin usage, the differences remained statistically significant with a higher hazard ratio (HR) for stroke/SEE in persistent AF [vs. paroxysmal AF, HR 1.87, 95% confidence interval (CI) 1.04-3.36; P = 0.037]. In 'high risk' patients (with >or=2 stroke risk factors) annual event rates for stroke/SEE were 2.08% for persistent AF and 1.27% for paroxysmal AF (adjusted HR = 1.68, 95% CI 0.91-3.1, P = 0.098). Elderly patients had annual event rates for stroke/SEE of 2.38% for persistent AF and 1.13% for paroxysmal AF (adjusted HR = 2.27, 95% CI 0.92-5.59, P = 0.075). Vitamin K antagonist (VKA)-naive paroxysmal AF patients had a 1.89%/year stroke/SEE rate, compared with 0.61% for previous VKA takers (HR = 0.33, 95% CI 0.11-1.01, P = 0.052). In this large clinical trial cohort of anticoagulated AF patients, those with paroxysmal AF had stroke rates which were lower than for patients with persistent AF, although both groups had broadly similar stroke risk factors. Subjects with paroxysmal AF at 'high risk' had stroke/SEE rates that were not significantly different to persistent AF subjects.

Circulating microRNA-1a is a biomarker of Graves' disease patients with atrial fibrillation.

PubMed

Wang, Fang; Zhang, Sheng-Jie; Yao, Xuan; Tian, Dong-Mei; Zhang, Ke-Qin; She, Dun-Min; Guo, Fei-Fan; Zhai, Qi-Wei; Ying, Hao; Xue, Ying

2017-07-01

It has been increasingly suggested that specific microRNAs expression profiles in the circulation and atrial tissue are associated with the susceptibility to atrial fibrillation. Nonetheless, the role of circulating microRNAs in Graves' disease patients with atrial fibrillation has not yet been well described. The objective of the study was to identify the role of circulating microRNAs as specific biomarkers for the diagnosis of Graves' disease with atrial fibrillation. The expression profiles of eight serum microRNAs, which are found to be critical in the pathogenesis of atrial fibrillation, were determined in patients with Graves' disease with or without atrial fibrillation. MicroRNA expression analysis was performed by real-time PCR in normal control subjects (NC; n = 17), patients with Graves' disease without atrial fibrillation (GD; n = 29), patients with Graves' disease with atrial fibrillation (GD + AF; n = 14), and euthyroid patients with atrial fibrillation (AF; n = 22). Three of the eight serum microRNAs,i.e., miR-1a, miR-26a, and miR-133, had significantly different expression profiles among the four groups. Spearman's correlation analysis showed that the relative expression level of miR-1a was positively correlated with free triiodothyronine (FT3) and free thyroxine (FT4), and negatively related to thyroid stimulating hormone. Spearman's correlations analysis also revealed that the level of miR-1a was negatively correlated with a critical echocardiographic parameter (left atrial diameter), which was dramatically increased in GD + AF group compared to GD group. Furthermore, the receiver-operating characteristic curve analysis indicated that, among the eight microRNAs, miR-1a had the largest area under the receiver-operating characteristic curves not only for discriminating between individuals with and without Graves' disease, but also for predicting the presence of atrial fibrillation in patients with Graves' disease. Our findings showed that the levels of serum miR-1a were significantly decreased in GD + AF group compared with GD group, suggesting that serum miR-1a might serve as a novel biomarker for diagnosis of atrial fibrillation in patients with Graves' disease.

Novel anticoagulants for stroke prevention in patients with atrial fibrillation.

PubMed

Jalota, A; Scarabelli, T M; Saravolatz, L; Bakhsh, M U; Agrawal, P; Jalota, R; Chen-Scarabelli, C; Fuster, V; Halperin, J

2014-06-01

Atrial fibrillation (AF) is the most common cardiac arrhythmia that can potentially result in stroke. Vitamin K antagonists (VKA) like warfarin were for many decades the only oral anticoagulants available for stroke prevention in patients with non-valvular atrial fibrillation (AF) at high risk of stroke. Recently, new oral anticoagulants (NOACS) have been introduced that act via direct inhibition of thrombin (dabigatran) or activated factor X (edoxaban, rivaroxaban and apixaban). Unlike VKAs, these anticoagulants do not require routine INR monitoring and posses favorable pharmacological properties. NOACs act rapidly, and have a stable and predictable dose-related anticoagulant effect with few clinically relevant drug-drug interactions. Phase III trials comparing these agents to warfarin for stroke prevention in patients with non-valvular AF demonstrated that they are at least as efficacious and safe as warfarin. Evolution of clinical guidelines to incorporate the new anticoagulants for stroke prevention in non-valvular AF may result in a reduction in the incidence of AF-related strokes. Safe and effective use of these new drugs in clinical practice requires understanding of their distinct pharmacological properties.

Atrial fibrillation in heart failure with preserved ejection fraction: Insights into mechanisms and therapeutics.

PubMed

Patel, Ravi B; Vaduganathan, Muthiah; Shah, Sanjiv J; Butler, Javed

2017-08-01

Atrial fibrillation (AF) and heart failure (HF) often coexist, and the outcomes of patients who have both AF and HF are considerably worse than those with either condition in isolation. Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous clinical entity and accounts for approximately one-half of current HF. At least one-third of patients with HFpEF are burdened by comorbid AF. The current understanding of the relationship between AF and HFpEF is limited, but the clinical implications are potentially important. In this review, we explore 1) the pathogenesis that drives AF and HFpEF to coexist; 2) pharmacologic therapies that may attenuate the impact of AF in HFpEF; and 3) future directions in the management of this complex syndrome. Copyright © 2016 Elsevier Inc. All rights reserved.

Risk factors for persistent atrial fibrillation following successful hyperthyroidism treatment with radioiodine therapy.

PubMed

Zhou, Zhen-Hu; Ma, Long-Le; Wang, Le-Xin

2011-01-01

To investigate the predicting factors for persistent atrial fibrillation (AF) following radioiodine therapy for hyperthyroidism. Standard 12-lead ECG and 24-h Holter monitoring were performed in 94 patients (38 males, mean age 46.1±8.2 years) with persistent AF following radioiodine therapy for hyperthyroidism. Left ventricular (LV) function was assessed with two-dimensional echocardiography. Euthyroidism or hypothyroidism was achieved in 81% and 19% of the patients, respectively, after radioiodine therapy. At the end of follow-up (1.6±1.3 years), LV ejection fraction in the 52 patients with LV dysfunction was increased from 39.3±3.3% to 59.0±5.5% (p<0.01). In the 38 patients with pre-treatment paroxysmal AF, no AF was documented during the follow-up. In the 45 patients with pre-treatment persistent AF, AF was found in 27 (60%) during the follow-up. Multivariate logistic regression analysis showed that more than 55 years old in age (RR 2.76, 95% CI: 1.16-8.79, p<0.01), duration of hyperthyroidism (RR 3.08, 95% CI: 1.22-11.41, p<0.01) and duration of pre-treatment atrial fibrillation (RR 2.96, 95% CI: 1.31-7.68, p<0.01) were independent predictors for persistent AF following radioiodine therapy. Older age, duration of hyperthyroidism and pre-treatment duration of AF are risk factors for persistent AF following radioiodine therapy.

Atrial fibrillation is associated with the fibrotic remodelling of adipose tissue in the subepicardium of human and sheep atria.

PubMed

Haemers, Peter; Hamdi, Hadhami; Guedj, Kevin; Suffee, Nadine; Farahmand, Patrick; Popovic, Natasa; Claus, Piet; LePrince, Pascal; Nicoletti, Antonino; Jalife, Jose; Wolke, Carmen; Lendeckel, Uwe; Jaïs, Pierre; Willems, Rik; Hatem, Stéphane N

2017-01-01

Accumulation of atrial adipose tissue is associated with atrial fibrillation (AF). However, the underlying mechanisms remain poorly understood. We examined the relationship between the characteristics of fatty infiltrates of the atrial myocardium and the history of AF. Atrial samples, collected in 92 patients during cardiac surgery and in a sheep model of persistent AF, were subjected to a detailed histological analysis. In sections of human right atrial samples, subepicardial fatty infiltrations were commonly observed in the majority of patients. A clear difference in the appearance and fibrotic content of these fatty infiltrations was observed. Fibro-fatty infiltrates predominated in patients with permanent AF (no AF: 37 ± 24% vs. paroxysmal AF: 50 ± 21% vs. permanent AF: 64 ± 23%, P < 0.001). An inverse correlation between fibrotic remodelling and the amount of subepicardial adipose tissue suggested the progressive fibrosis of fatty infiltrates with permanent AF. This hypothesis was tested in a sheep model of AF. In AF sheep, an increased accumulation of peri-atrial fat depot was observed on cardiac magnetic resonance imaging and dense fibro-fatty infiltrations predominated in the left atria of AF sheep. Cellular inflammation, mainly consisting of functional cytotoxic T lymphocytes, was observed together with adipocyte cell death in human atria. Atrial fibrillation is associated with the fibrosis of subepicardial fatty infiltrates, a process in which cytotoxic lymphocytes might be involved. This remodelling of the atrial subepicardium could contribute to structural remodelling forming a substrate for AF. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

Pathophysiologic correlates of thromboembolism in nonvalvular atrial fibrillation: I. Reduced flow velocity in the left atrial appendage (The Stroke Prevention in Atrial Fibrillation [SPAF-III] study).

PubMed

Goldman, M E; Pearce, L A; Hart, R G; Zabalgoitia, M; Asinger, R W; Safford, R; Halperin, J L

1999-12-01

Stroke associated with atrial fibrillation (AF) is mainly due to embolism of thrombus formed during stasis of blood in the left atrial appendage (LAA). Pathophysiologic correlates of appendage flow velocity as assessed by transesophageal echocardiography (TEE) in patients with AF have not been defined. To evaluate the hypothesis that reduced velocity is associated with spontaneous echocardiographic contrast and thrombus in the LAA and with clinical embolic events, we measured LAA flow velocity by TEE in 721 patients with nonvalvular AF entering the Stroke Prevention in Atrial Fibrillation (SPAF-III) study. Patient features, TEE findings, and subsequent cardioembolic events were correlated with velocity by multivariate analysis. Patients in AF during TEE displayed lower peak antegrade (emptying) flow velocity (Anu(p)) than those with intermittent AF in sinus rhythm during TEE (33 cm/s vs 61 cm/s, respectively, P <.0001). Anu(p) < 20 cm/s was associated with dense spontaneous echocardiographic contrast (P <.001), appendage thrombus (P <.01), and subsequent cardioembolic events (P <.01). Independent predictors of Anu(p) < 20 cm/s included age (P =.009), systolic blood pressure (P <.001), sustained AF (P =.01), ischemic heart disease (P =.01), and left atrial area (P =.04). Multivariate analysis found both Anu(p) <20 cm/s (relative risk 2.6, P =.02) and clinical risk factors (relative risk 3.3, P =.002) independently associated with LAA thrombus. LAA Anu(p) is reduced in AF and associated with spontaneous echocardiographic contrast, appendage thrombus, and cardioembolic stroke. Systolic hypertension and aortic atherosclerosis, independent clinical predictors of stroke in patients with AF, also correlated with LAA Anu(p). Our results support the role of reduced LAA Anu(p) in the generation of stasis, thrombus formation, and embolism in patients with AF, although other mechanisms also contribute to stroke.

Addressing the management of atrial fibrillation - a systematic review of the role of dronedarone.

PubMed

Podda, Gian Marco; Casazza, Giovanni; Casella, Francesco; Dipaola, Franca; Scannella, Emanuela; Tagliabue, Ludovica

2012-01-01

Atrial fibrillation (AF) is the most common sustained arrhythmia. It occurs in 1%-2% of the general population and its prevalence increases with age. Dronedarone, a noniodinated benzofuran similar to amiodarone, was developed as an antiarrhythmic agent for patients with atrial fibrillation. The aim of our systematic review was to critically evaluate randomized controlled trials that compared treatment with dronedarone versus placebo or amiodarone in patients with atrial fibrillation. Electronic databases (MEDLINE, Embase, and Central) were searched up to November 2011 with no language restrictions. We included randomized controlled trials in which dronedarone was compared to placebo or other drugs in patients with AF. Internal and external validity was assessed. We identified seven papers corresponding to eight randomized controlled trials. The DAFNE, EURIDIS/ADONIS, and ATHENA trials demonstrated a reduction of AF recurrence with dronedarone as compared to placebo in patients with nonpermanent AF. The DIONYSOS study showed that dronedarone is less effective for the prevention of recurrent AF but improved tolerability as compared to amiodarone. Considering patients with permanent AF, the ERATO trial showed that dronedarone had rate-control effects while the PALLAS study was stopped early since stroke, myocardial infarction, systemic embolism, or death from cardiovascular causes were significantly more frequent in subjects treated with dronedarone as compared to placebo. The ANDROMEDA trial included patients with recent hospitalization for heart failure and was terminated early because of excess of deaths in the dronedarone group. Like most antiarrhythmic drugs, dronedarone reduces the recurrence of AF in patients with paroxysmal or persistent AF as compared to placebo. However, relapse rates in the first year of therapy are high. Moreover, dronedarone showed to be less effective than amiodarone. Finally, dronedarone should be avoided in patients with permanent AF and a high risk for cardiovascular events or severe congestive heart failure.

ROCKET AF adds more concerns about Digoxin safety in patients with atrial fibrillation

PubMed Central

ElMaghawry, Mohamed

2015-01-01

In a recent article in the Journal, we have reviewed the adverse cardiovascular outcomes observed with digoxin use in the PALLAS study.1 The PALLAS study was designed to determine if dronedarone would reduce major vascular events in patients with permanent atrial fibrillation (AF).2 However the study was stopped early because of safety reasons, as a significant number of patients on the dronedarone arm reached the co-primary end point composite of stroke, myocardial infarction, systemic embolism, or cardiovascular death. Data sub-analyses suggested that digoxin-dronedarone interaction was responsible for the higher arrhythmic death rate observed in the trial. These observations are consistent with several other studies that demonstrate the potential hazard of the use of digoxin in heart failure and/or atrial fibrillation. A more recent article published in the Lancet studied the use and outcomes of digoxin in the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism in Atrial Fibrillation (ROCKET AF) trial.3 The investigators concluded that digoxin treatment was associated with a significant increase in all-cause mortality, vascular death, and sudden death in patients with AF. PMID:26779514

New antiarrhythmic agents for atrial fibrillation and atrial flutter: United States drug market response as an indicator of acceptance.

PubMed

LaPointe, Nancy M Allen; Pamer, Carol A; Kramer, Judith M

2003-10-01

To determine how well dofetilide and Betapace AF (sotalol, approved solely for atrial fibrillation and atrial flutter), with their detailed dosing and monitoring guidelines for safety, were accepted into clinical practice during the 2 calendar years after their introduction. We reviewed the number of new, refill, and total prescriptions of all antiarrhythmic agents in the United States from April 2000-December 2001 to assess use of dofetilide and Betapace AF in the drug market. Both were prescribed very infrequently throughout the study period. In addition, the infrequent reported use of these drugs for patients with atrial fibrillation and flutter indicated poor acceptance of these agents by prescribing physicians. We speculated that the restricted distribution and required educational program for dofetilide, as well as the availability of generic sotalol products, may have discouraged physicians from prescribing both dofetilide and Betapace AE CONCLUSION: A common goal for both the dofetilide risk-management program and the creation of a sotalol product indicated solely for atrial fibrillation and atrial flutter was to provide safer treatment for patients with these arrhythmias. Unfortunately, limited penetration of dofetilide and Betapace AF into the U.S. market suggests that drugs without a risk-management program or detailed dosing guidelines were more likely than dofetilide or Betapace AF to be selected for treatment of atrial fibrillation and atrial flutter.

Ablation for Atrial Fibrillation

PubMed Central

2006-01-01

Executive Summary Objective To review the effectiveness, safety, and costing of ablation methods to manage atrial fibrillation (AF). The ablation methods reviewed were catheter ablation and surgical ablation. Clinical Need Atrial fibrillation is characterized by an irregular, usually rapid, heart rate that limits the ability of the atria to pump blood effectively to the ventricles. Atrial fibrillation can be a primary diagnosis or it may be associated with other diseases, such as high blood pressure, abnormal heart muscle function, chronic lung diseases, and coronary heart disease. The most common symptom of AF is palpitations. Symptoms caused by decreased blood flow include dizziness, fatigue, and shortness of breath. Some patients with AF do not experience any symptoms. According to United States data, the incidence of AF increases with age, with a prevalence of 1 per 200 people aged between 50 and 60 years, and 1 per 10 people aged over 80 years. In 2004, the Institute for Clinical Evaluative Sciences (ICES) estimated that the rate of hospitalization for AF in Canada was 582.7 per 100,000 population. They also reported that of the patients discharged alive, 2.7% were readmitted within 1 year for stroke. One United States prevalence study of AF indicated that the overall prevalence of AF was 0.95%. When the results of this study were extrapolated to the population of Ontario, the prevalence of AF in Ontario is 98,758 for residents aged over 20 years. Currently, the first-line therapy for AF is medical therapy with antiarrhythmic drugs (AADs). There are several AADs available, because there is no one AAD that is effective for all patients. The AADs have critical adverse effects that can aggravate existing arrhythmias. The drug selection process frequently involves trial and error until the patient’s symptoms subside. The Technology Ablation has been frequently described as a “cure” for AF, compared with drug therapy, which controls AF but does not cure it. Ablation involves directing an energy source at cardiac tissue. For instance, radiofrequency energy uses heat to burn tissue near the source of the arrhythmia. The purpose is to create a series of scar tissue, so that the aberrant electrical pathways can no longer exist. Because the pulmonary veins are the predominant source of AF initiation, the primary goal of ablation is to isolate the pulmonary veins from the left atria through the creation of a conduction block. There are 2 methods of ablation: catheter ablation and surgical (operative) ablation. Radiofrequency energy is most commonly used for ablation. Catheter ablation involves inserting a catheter through the femoral vein to access the heart and burn abnormal foci of electrical activity by direct contact or by isolating them from the rest of the atrium. The surgical ablation is performed minimally invasively via direct visualization or with the assistance of a special scope for patients with lone AF. Review Strategy In March 2006, the following databases were searched: Cochrane Library International Agency for Health Technology Assessment (first quarter 2006), Cochrane Database of Systematic Reviews (first quarter 2006), Cochrane Central Register of Controlled Trials (first quarter 2006), MEDLINE (1966 to February 2006), MEDLINE In-Process and Other Non-indexed Citations (1966 to March 1, 2006), and EMBASE (1980 to 2006 week 9). The Medical Advisory Secretariat also searched Medscape on the Internet for recent reports on trials that were unpublished but that were presented at international conferences. In addition, the Web site Current Controlled Trials (www.controlled-trials.com) was searched for ongoing trials investigating ablation for atrial fibrillation. Search terms included: radiofrequency ablation, catheter ablation and atrial fibrillation. Summary of Findings Sixteen RCTs were identified that compared ablation methods in patients with AF. Two studies were identified that investigated first-line therapy for AF or atrial flutter. Seven other studies examined patients with drug-refractory, lone AF; and the remaining 7 RCTs compared ablation plus heart surgery to heart surgery alone in patients with drug-refractory AF and concomitant heart conditions. First-line Catheter Ablation for Atrial Fibrillation or Atrial Flutter Both studies concluded that catheter ablation was associated with significantly improved long-term freedom from arrhythmias and quality of life compared with medical therapy. These studies included different patient populations (those with AF in one pilot study, and those with atrial flutter in the other). Catheter ablation as first-line treatment is considered experimental at this time. Catheter Ablation Versus Medical Therapy in Patients With Drug-Refractory, Lone Atrial Fibrillation In this review, catheter ablation had success rates (freedom from arrhythmia) that ranged from 42% to 90% (median, 74%) in patients with drug-refractory, lone AF. All 3 of the RCTs comparing catheter ablation to medical therapy in patients with drug-refractory, lone AF found a significant improvement in terms of freedom from arrhythmia over a minimum of 12 months follow-up (P<.05). Ablation Plus Heart Surgery Versus Heart Surgery Alone in Patients With Atrial Fibrillation It is clear that patients with drug-refractory AF who are undergoing concomitant heart surgery (usually mitral valve repair or replacement) benefit significantly from surgical ablation, in terms of long-term freedom from AF, without substantial additional risk compared to open heart surgery alone. This group of patients represents about 1% of the patients with atrial fibrillation, thus the majority of the burden of AF lies within the patients with lone AF (i.e. those not requiring additional heart surgery). Conclusion Catheter ablation appears to be an effective treatment for patients with drug-refractory AF whose treatment alternatives are limited. Ablation technology is continually evolving with increasing success rates associated with the ablation procedure. PMID:23074498

Health Literacy and Awareness of Atrial Fibrillation.

PubMed

Reading, Stephanie R; Go, Alan S; Fang, Margaret C; Singer, Daniel E; Liu, In-Lu Amy; Black, Mary Helen; Udaltsova, Natalia; Reynolds, Kristi

2017-04-11

Atrial fibrillation (AF) is the most common clinically significant arrhythmia in adults and a major risk factor for ischemic stroke. Nonetheless, previous research suggests that many individuals diagnosed with AF lack awareness about their diagnosis and inadequate health literacy may be an important contributing factor to this finding. We examined the association between health literacy and awareness of an AF diagnosis in a large, ethnically diverse cohort of Kaiser Permanente Northern and Southern California adults diagnosed with AF between January 1, 2006 and June 30, 2009. Using self-reported questionnaire data completed between May 1, 2010 and September 30, 2010, awareness of an AF diagnosis was evaluated using the question "Have you ever been told by a doctor or other health professional that you have a heart rhythm problem called atrial fibrillation or atrial flutter?" and health literacy was assessed using a validated 3-item instrument examining problems because of reading, understanding, and filling out medical forms. Of the 12 517 patients diagnosed with AF, 14.5% were not aware of their AF diagnosis and 20.4% had inadequate health literacy. Patients with inadequate health literacy were less likely to be aware of their AF diagnosis compared with patients with adequate health literacy (prevalence ratio=0.96; 95% CI [0.94, 0.98]), adjusting for sociodemographics, health behaviors, and clinical characteristics. Lower health literacy is independently associated with less awareness of AF diagnosis. Strategies designed to increase patient awareness of AF and its complications are warranted among individuals with limited health literacy. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

The Stressors and Coping Strategies of Older Adults With Persistent Atrial Fibrillation Prior to and Following Direct Current Cardioversion.

PubMed

Rush, Kathy L; Hatt, Linda; Shay, Matt; Gorman, Nicole; Laberge, Carol G; Reid, R Colin; Wilson, Ryan

2017-09-01

The purpose of this study was to explore the stressors and coping strategies of older adults with persistent atrial fibrillation (AF) before and after direct current cardioversion. The study used a qualitative descriptive design. Sixteen patients were recruited through an AF clinic to participate in individual interviews prior to the cardioversion and at 6 and 12 weeks post procedure. Pre-cardioversion, older adults experienced symptom and health care-related stressors superimposed on existing non-AF stressors. They used a range of emotion and problem-focused coping. Non-AF stressors increased post procedure at the same time that participants perceived less need for coping strategies with a return to regular rhythm. There was a shift from AF to non-AF related stressors following the cardioversion but a decrease in coping strategies. Older adults with AF should be encouraged to maintain use of coping strategies to manage ongoing stress and reduce the risk of AF recurrence.

Mechanisms for the Termination of Atrial Fibrillation by Localized Ablation: Computational and Clinical Studies.

PubMed

Rappel, Wouter-Jan; Zaman, Junaid A B; Narayan, Sanjiv M

2015-12-01

Human atrial fibrillation (AF) can terminate after ablating localized regions, which supports the existence of localized rotors (spiral waves) or focal drivers. However, it is unclear why ablation near a spiral wave tip would terminate AF and not anchor reentry. We addressed this question by analyzing competing mechanisms for AF termination in numeric simulations, referenced to clinical observations. Spiral wave reentry was simulated in monodomain 2-dimensional myocyte sheets using clinically realistic rate-dependent values for repolarization and conduction. Heterogeneous models were created by introduction of parameterized variations in tissue excitability. Ablation lesions were applied as nonconducting circular regions. Models confirmed that localized ablation may anchor spiral wave reentry, producing organized tachycardias. Several mechanisms referenced to clinical observations explained termination of AF to sinus rhythm. First, lesions may create an excitable gap vulnerable to invasion by fibrillatory waves. Second, ablation of rotors in regions of low-excitability (from remodeling) produced re-entry in more excitable tissue allowing collision of wavefront and back. Conversely, ablation of rotors in high-excitability regions migrated spiral waves to less excitable tissue, where they detached to collide with nonconducting boundaries. Third, ablation may connect rotors to nonconducting anatomic orifices. Fourth, reentry through slow-conducting channels may terminate if ablation closes these channels. Limited ablation can terminate AF by several mechanisms. These data shed light on how clinical AF may be sustained in patients' atria, emphasizing heterogeneities in tissue excitability, slow-conducting channels, and obstacles that are increasingly detectable in patients and should be the focus of future translational studies. © 2015 American Heart Association, Inc.

Apixaban versus Warfarin for the Prevention of Periprocedural Cerebral Thromboembolism in Atrial Fibrillation Ablation: Multicenter Prospective Randomized Study.

PubMed

Kuwahara, Taishi; Abe, Mitsunori; Yamaki, Masaru; Fujieda, Hiroyuki; Abe, Yumiko; Hashimoto, Katsushi; Ishiba, Misako; Sakai, Hirotsuka; Hishikari, Keiichi; Takigawa, Masateru; Okubo, Kenji; Takagi, Katsumasa; Tanaka, Yasuaki; Nakajima, Jun; Takahashi, Atsushi

2016-05-01

Stroke can be a life-threatening complication of atrial fibrillation (AF) catheter ablation. Uninterrupted warfarin treatment contributes to minimizing the risk of stroke complications. This was a prospective, open-label, randomized, multicenter study assessing the safety and efficacy of apixaban for the prevention of cerebral thromboembolism complicating AF catheter ablation. Two hundred patients with drug-resistant AF were equally assigned to take either apixaban (5 mg or 2.5 mg twice daily) or warfarin (target international normalized ratio, 2-3) for at least 1 month before AF ablation. Neither drug regimen was interrupted throughout the operative period. Diffusion-weighted magnetic resonance imaging was performed for all patients to detect silent cerebral infarction (SCI) after the ablation. Primary outcomes were defined as the occurrence of stroke, transient ischemic attack, SCI, or major bleeding that required intervention. The secondary outcome was minor bleeding. The groups did not statistically differ in patients' backgrounds or procedural parameters. During AF ablation, the apixaban group required administration of more heparin to maintain an activated clotting time > 300 seconds than the warfarin group (apixaban, 14,000 ± 4,000 units; warfarin, 9,000 ± 3,000 units). Three primary outcome events occurred in each group (apixaban, 2 SCI and 1 major bleed; warfarin, 3 SCI, P = 1.00), and 3 and 4 secondary outcome events occurred in the apixaban and warfarin groups (P = 0.70), respectively. Apixaban has similar safety and effectiveness to warfarin for the prevention of cerebral thromboembolism during the periprocedural period of AF ablation. © 2016 Wiley Periodicals, Inc.

The cost of atrial fibrillation in Italy: a five-year analysis of healthcare expenditure in the general population. From the Italian Survey of Atrial Fibrillation Management (ISAF) study.

PubMed

Zoni Berisso, M; Landolina, M; Ermini, G; Parretti, D; Zingarini, G L; Degli Esposti, L; Cricelli, C; Boriani, G

2017-01-01

Atrial fibrillation (AF) is a relevant item of expenditure for the National Healthcare systems. The aim of the study was to estimate the annual costs of AF in Italy. The Italian Survey of Atrial Fibrillation Management Study enrolled 6.036 patients with AF among 295.906 subjects representative of the Italian population. Data were collected by 233 General Practitioners (GPs) distributed across Italy. Quantities of resources used during the 5 years preceding the ISAF screening were inferred from the survey data and multiplied by the current Italian unit costs of 2015 in order to estimate the mean per patient annual cumulative cost of AF. Patients were subdivided on the basis of the number of hospitalizations, invasive/non-invasive diagnostic tests and invasive therapeutic procedures in 3 different clinical subsets: "low cost", " medium cost" and "high cost clinical scenario". The estimated mean costs per patient per year were 613 €, 891 € and 1213 € for the "Low cost", "Medium cost" and "High Cost Clinical Scenario" respectively. Hospitalizations and inpatient interventional procedures accounted for more than 80% of the cumulative annual costs. The mean annual costs among patients pursuing "Rhythm control" strategy was 956 €. In Italy, the estimated costs of AF per patient per year are lower than those reported in other developed countries and vary widely related to the different characteristics of AF patients. Hospitalizations and interventional procedures are the main drivers of costs. The mean annual cost of AF is mainly influenced by the duration of the period of observation and the patients' characteristics. Measures to reduce hospitalizations are needed.

Racial/ethnic differences in atrial fibrillation symptoms, treatment patterns, and outcomes: Insights from Outcomes Registry for Better Informed Treatment for Atrial Fibrillation Registry.

PubMed

Golwala, Harsh; Jackson, Larry R; Simon, DaJuanicia N; Piccini, Jonathan P; Gersh, Bernard; Go, Alan S; Hylek, Elaine M; Kowey, Peter R; Mahaffey, Kenneth W; Thomas, Laine; Fonarow, Gregg C; Peterson, Eric D; Thomas, Kevin L

2016-04-01

Significant racial/ethnic differences exist in the incidence of atrial fibrillation (AF). However, less is known about racial/ethnic differences in quality of life (QoL), treatment, and outcomes associated with AF. Using data from the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation, we compared clinical characteristics, QoL, management strategies, and long-term outcomes associated with AF among various racial/ethnic groups. We analyzed 9,542 participants with AF (mean age 74 ± 11 years, 43% women, 91% white, 5% black, 4% Hispanic) from 174 centers. Compared with AF patients identified as white race, patients identified as Hispanic ethnicity and those identified as black race were younger, were more often women, and had more cardiac and noncardiac comorbidities. Black patients were more symptomatic with worse QoL and were less likely to be treated with a rhythm control strategy than other racial/ethnic groups. There were no significant racial/ethnic differences in CHA2DS2-VASc stroke or ATRIA bleeding risk scores and rates of oral anticoagulation use were similar. However, racial and ethnic minority populations treated with warfarin spent a lower median time in therapeutic range of international normalized ratio (59% blacks vs 68% whites vs 62% Hispanics, P < .0001). There was no difference in long-term outcomes associated with AF between the 3 groups at a median follow-up of 2.1 years. Relative to white and Hispanic patients, black patients with AF had more symptoms, were less likely to receive rhythm control interventions, and had lower quality of warfarin management. Despite these differences, clinical events at 2 years were similar by race and ethnicity. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Micromechanical testing of individual collagen fibrils.

PubMed

van der Rijt, Joost A J; van der Werf, Kees O; Bennink, Martin L; Dijkstra, Pieter J; Feijen, Jan

2006-09-15

A novel method based on AFM was used to attach individual collagen fibrils between a glass surface and the AFM tip, to allow force spectroscopy studies of these. The fibrils were deposited on glass substrates that are partly coated with Teflon AF. A modified AFM tip was used to accurately deposit epoxy glue droplets on either end of the collagen fibril that cross the glass-Teflon AF interface, as to such attach it with one end to the glass and the other end to the AFM tip. Single collagen fibrils have been mechanically tested in ambient conditions and were found to behave reversibly up to stresses of 90 MPa. Within this regime a Young's modulus of 2-7 GPa was obtained. In aqueous media, the collagen fibrils could be tested reversibly up to about 15 MPa, revealing Young's moduli ranging from 0.2 to at most 0.8 GPa.

[Characteristics and outcome of acute ischemic stroke patients with atrial fibrillation].

PubMed

Li, Shenjun; Wang, Shucai; Gu, Mingming; Cao, Bingzhen

2015-11-17

To evaluate clinical characteristics and outcome of acute ischemic stroke patients with atrial fibrillation. Consecutive acute ischemic stroke patients who were hospitalized in the neurology department of General Hospital of Jinan Military Region were prospectively recruited from August 2010 to November 2013.The baseline datum including age, sex, National Institute of Health Stroke Scale (NIHSS), type of Oxfordshire Community Stroke Project (OCSP: total anterior circulation infarct, partial anterior circulation infarction, posterior circulation infarction and lacunar infarction), serum creatinine, serum albumin levels etc.were recorded.Atrial fibrillation (AF) was defined as a history of persistent atrial fibrillation or paroxysmal atrial fibrillation, supported by past electrocardiogram or diagnosed by the attending physicians based on physical examination, electrocardiogram and/or 24-hour electrocardiogram monitoring during hospitalization. Outcome was assessed by modified Rankin Scale (mRS) which was obtained 180 days after stroke by telephone interview (mRS ≤ 2 reflected good prognosis, and mRS>2 reflected unfavorable prognosis), and death defined as all-cause mortality. Multivariate regression model was used to analyze predictors of mortality and disability. Of the 965 patients included in this study, 113 (11.71%) had AF; valvular AF was observed in 11 patients (9.7%) among them.Only 4 patients with valvular AF and none of the patients with non-valvular AF took warfarin before the stroke event. 14.2% (16/113) acute ischemic stroke patients with AF took aspirin. Compared to patients without AF, patients with AF had a higher NIHSS score on admission (median 11 vs 5, P=0.000); were more often with diabetes (26.55% vs 9.74%, P=0.028), congestive heart failure (12.37% vs 11.03%, P=0.000), prior stroke (31.86% vs 21.83%, P=0.023), total anterior circulation infarct subtype (51.33% vs 19.37%, P=0.000); they were less often smokers (20.35% vs 37.32%, P=0.000), alcohol consumers (13.27% vs 27.58%, P=0.001), partial anterior circulation infarction subtype (24.78% vs 36.74%, P=0.012), lacunar infarct subtype (0 vs 17.61%, P=0.000); they had less often experienced myocardial infarction (11.50% vs 11.74%, P=0.041). AF was a significant independent prognostic factor for long-term poor outcomes (OR=2.227, 95%CI: 1.262-3.933, P=0.006). Oral anticoagulants are underused in AF patients.Brain infarction patients with AF is more severe than patients without AF; have higher frequency of total anterior circulation infarct subtype, prior stroke and lower frequency of lacunar infarct subtype. AF is a significant independent prognostic factor for long-term poor outcome in patients with acute brain infarction.

Characteristics and outcomes of atrial fibrillation patients with or without specific symptoms: results from the PREFER in AF registry.

PubMed

Bakhai, Ameet; Darius, Harald; De Caterina, Raffaele; Smart, Angela; Le Heuzey, Jean-Yves; Schilling, Richard John; Zamorano, José Luis; Shah, Mit; Bramlage, Peter; Kirchhof, Paulus

2016-10-01

Atrial fibrillation (AF) is a common condition that is a major cause of stroke. A significant proportion of patients with AF are not classically symptomatic at diagnosis or soon after diagnosis. There is little information comparing their characteristics, treatment, and outcomes of patients with symptoms, which predominate in clinical trials to those without. We analysed data from the Prevention of Thromboembolic Events-European Registry in Atrial Fibrillation. This was a prospective, real-world registry with a 12-month follow-up that included AF patients aged 18 years and over. Patients were divided into those with and without AF symptoms using the European Heart Rhythm Association (EHRA) score (Category I vs. Categories II-IV). Of the 6196 patients (mean age 72 years) with EHRA scores available, 501 (8.1%) were asymptomatic. A lower proportion of asymptomatic patients was female (22.8 vs. 41.2%), with less noted to have heart failure and coronary artery disease (P < 0.01 for all). There were no differences in terms of the prevalence of diabetes, obesity, or prior stroke. Asymptomatic patients had a lower CHA2DS2-VASc score (2.9 ± 1.7 vs. 3.4 ± 1.8; P < 0.01) and HAS-BLED score (1.8 ± 1.1 vs. 2.1 ± 1.2; P < 0.01). During the 1-year follow-up, adverse events occurred at similar frequencies in asymptomatic and symptomatic patients (1.6 vs. 0.8% for ischaemic stroke; P = 0.061; 1.4 vs. 1.3% for transient ischaemic attack; P = 0.840). Patients with higher CHA2DS2-VASc and HAS-BLED scores experienced more events, independent of symptoms. Antithrombotic therapy was comparable for both groups at baseline and at follow-up. The similar clinical characteristics and frequency of adverse events between asymptomatic and symptomatic AF patients revives the question of whether screening programmes to detect people with asymptomatic AF are worthwhile, particularly in those aged 65 and over potentially likely to have clinical and economic benefits from anticoagulants. This evidence may be informative if clinicians may not be comfortable participating in future clinical trials, leaving asymptomatic patients with AF and high stroke risk without anticoagulation.

Improving cost-effectiveness of and outcomes from drug therapy in patients with atrial fibrillation in managed care: role of the pharmacist.

PubMed

Johnson, Samuel G

2009-08-01

The medical care costs for procedures, medications, and testing associated with atrial fibrillation (AF) in the United States are high and projected to increase markedly in the future as the number of Americans affected grows. The burden on patient quality of life, the health care system, and society are pharmacoeconomic considerations in managing AF. To identify key pharmacoeconomic considerations in managing AF and describe ways in which managed care pharmacists can improve the cost-effectiveness of and outcomes from drug therapy for AF. The high medical care costs of AF are largely the result of the high cost of hospitalization and inpatient procedures. Recurrence of AF dramatically increases costs, especially for hospital care. Managed care pharmacists have many opportunities to provide cost-effective care to and improve outcomes in patients with AF. Policy and process review, population management, and case management are key strategies for improving outcomes in patients with AF. Pharmacist input into policy and process review, including pharmacy benefits design, formulary management, and the use of information technology, can help ensure that the use of drug therapy for AF is cost-effective. Population management strategies, such as development of clinical pathways and patient registries, seek to improve the quality, consistency, and cost-effectiveness of care and the likelihood that desired therapeutic outcomes are achieved through targeted interventions. Case management strategies focus on longitudinal care for individuals in order to improve quality. Pharmacist-managed anticoagulation services and antiarrhythmic drug monitoring are the 2 most widely known case management strategies for patients with AF. Managed care pharmacists can screen patients with AF for the use of anticoagulation, which is needed to prevent embolic stroke but is under-used, even though recommended by evidence-based guidelines. The clinical efficacy and cost-effectiveness of pharmacist-managed anticoagulation services for patients with AF are well documented. Pharmacist-managed antiarrhythmic drug monitoring is a less well-known case management strategy that facilitates early detection and intervention to minimize toxicity. Managed care pharmacists can play an instrumental role in implementing strategies to improve the cost-effectiveness of and outcomes from drug therapy for AF.

Robust tracking of a virtual electrode on a coronary sinus catheter for atrial fibrillation ablation procedures

NASA Astrophysics Data System (ADS)

Wu, Wen; Chen, Terrence; Strobel, Norbert; Comaniciu, Dorin

2012-02-01

Catheter tracking in X-ray fluoroscopic images has become more important in interventional applications for atrial fibrillation (AF) ablation procedures. It provides real-time guidance for the physicians and can be used as reference for motion compensation applications. In this paper, we propose a novel approach to track a virtual electrode (VE), which is a non-existing electrode on the coronary sinus (CS) catheter at a more proximal location than any real electrodes. Successful tracking of the VE can provide more accurate motion information than tracking of real electrodes. To achieve VE tracking, we first model the CS catheter as a set of electrodes which are detected by our previously published learning-based approach.1 The tracked electrodes are then used to generate the hypotheses for tracking the VE. Model-based hypotheses are fused and evaluated by a Bayesian framework. Evaluation has been conducted on a database of clinical AF ablation data including challenging scenarios such as low signal-to-noise ratio (SNR), occlusion and nonrigid deformation. Our approach obtains 0.54mm median error and 90% of evaluated data have errors less than 1.67mm. The speed of our tracking algorithm reaches 6 frames-per-second on most data. Our study on motion compensation shows that using the VE as reference provides a good point to detect non-physiological catheter motion during the AF ablation procedures.2

Left atrial thrombus and dense spontaneous echocardiographic contrast in patients on continuous direct oral anticoagulant therapy undergoing catheter ablation of atrial fibrillation: Comparison of dabigatran, rivaroxaban, and apixaban.

PubMed

Wu, Michael; Gabriels, James; Khan, Mohammad; Shaban, Nada; D'Amato, Salvatore; Liu, Christopher F; Markowitz, Steven M; Ip, James E; Thomas, George; Singh, Parmanand; Lerman, Bruce; Patel, Apoor; Cheung, Jim W

2018-04-01

Left atrial thrombus (LAT) and dense spontaneous echocardiographic contrast (SEC) detected by transesophageal echocardiography (TEE) in patients on continuous direct oral anticoagulants (DOAC) therapy before catheter ablation of atrial fibrillation (AF) or atrial flutter (AFL) have been described. We sought to compare rates of TEE-detected LAT and dense SEC among patients taking different DOACs. We evaluated 609 consecutive patients from 3 tertiary hospitals (median age 65 years; interquartile range 58-71 years; 436 (72%) men) who were on ≥4 weeks of continuous DOAC therapy (dabigatran, n = 166 [27%]; rivaroxaban, n = 257 [42%]; or apixaban, n = 186 [31%]) undergoing TEE before catheter ablation of AF/AFL. Demographic, clinical, and TEE data were collected for each patient. Despite ≥4 weeks of continuous DOAC therapy, 17 patients (2.8%) had LAT and 15 patients (2.5%) had dense SEC detected by TEE. The rates of LAT were 3.0%, 3.5%, and 1.6% for patients on dabigatran, rivaroxaban, and apixaban, respectively (P = .482). The rates of dense SEC were 1.2%, 3.5%, and 2.2% for patients on dabigatran, rivaroxaban, and apixaban, respectively (P = .299). Congestive heart failure (odds ratio 4.4; 95% confidence interval 1.6-12; P = .003) and moderate/severe left atrial enlargement (odds ratio 3.1; 95% confidence interval 1.1-8.6; P = .026) were independent predictors of LAT. In this study, ∼3% of patients on continuous DOAC therapy had LAT detected before catheter ablation of AF/AFL. Specific DOAC therapy did not significantly affect the rates of LAT detection. Copyright © 2017 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

In permanent atrial fibrillation, PDE3 reduces force responses to 5‐HT, but PDE3 and PDE4 do not cause the blunting of atrial arrhythmias

PubMed Central

Schwarz, Simon; Ravens, Ursula; Knaut, Michael

2016-01-01

Abstract Background and Purpose 5‐HT increases force and L‐type Ca2 + current (ICa,L) and causes arrhythmias through 5‐HT4 receptors in human atrium. In permanent atrial fibrillation (peAF), atrial force responses to 5‐HT are blunted, arrhythmias abolished but ICa,L responses only moderately attenuated. We investigated whether, in peAF, this could be due to an increased function of PDE3 and/or PDE4, using the inhibitors cilostamide (300 nM) and rolipram (1 μM) respectively. Experimental Approach Contractile force, arrhythmic contractions and ICa,L were assessed in right atrial trabeculae and myocytes, obtained from patients with sinus rhythm (SR), paroxysmal atrial fibrillation (pAF) and peAF. Key Results Maximum force responses to 5‐HT were reduced to 15% in peAF, but not in pAF. Cilostamide, but not rolipram, increased both the blunted force responses to 5‐HT in peAF and the inotropic potency of 5‐HT fourfold to sevenfold in trabeculae of patients with SR, pAF and peAF. Lusitropic responses to 5‐HT were not decreased in peAF. Responses of ICa,L to 5‐HT did not differ and were unaffected by cilostamide or rolipram in myocytes from patients with SR or peAF. Concurrent cilostamide and rolipram increased 5‐HT's propensity to elicit arrhythmias in trabeculae from patients with SR, but not with peAF. Conclusions and Implications PDE3, but not PDE4, reduced inotropic responses to 5‐HT in peAF, independently of lusitropy and ICa,L, but PDE3 activity was the same as that in patients with SR and pAF. Atrial remodelling in peAF abolished the facilitation of 5‐HT to induce arrhythmias by inhibition of PDE3 plus PDE4. PMID:27238373

Alcohol and Atrial Fibrillation: A Sobering Review.

PubMed

Voskoboinik, Aleksandr; Prabhu, Sandeep; Ling, Liang-Han; Kalman, Jonathan M; Kistler, Peter M

2016-12-13

Alcohol is popular in Western culture, supported by a perception that modest intake is cardioprotective. However, excessive drinking has detrimental implications for cardiovascular disease. Atrial fibrillation (AF) following an alcohol binge or the "holiday heart syndrome" is well characterized. However, more modest levels of alcohol intake on a regular basis may also increase the risk of AF. The pathophysiological mechanisms responsible for the relationship between alcohol and AF may include direct toxicity and alcohol's contribution to obesity, sleep-disordered breathing, and hypertension. We aim to provide a comprehensive review of the epidemiology and pathophysiology by which alcohol may be responsible for AF and determine whether alcohol abstinence is required for patients with AF. Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Role of Echocardiography in the Management and Prognosis of Atrial Fibrillation

PubMed Central

Silverman, David I; Ayirala, Srilatha R; Manning, Warren J

2012-01-01

Echocardiography plays a longstanding and vital role in the management of atrial fibrillation (AF). Advances in 2D imaging, Doppler echocardiography and strain imaging have all contributed to major progress in AF treatment. Echocardiographically measured left atrial (LA) volume is a powerful predictor of maintenance of sinus rhythm following cardioversion as well as risk of thrombus formation and thromboembolism. Doppler derived parameters of atrial mechanical function including atrial ejection force provide related prognostic information. Transesophageal echocardiocardiograpy (TEE) guided cardioversion of AF allows for rapid conversion to sinus rhythm without prolonged oral anticoagulation, and TEE serves as a useful tool during catheter ablation of AF and atrial flutter. Newer measures derived from speckle tracking offer great promise in further improving the care of patients with AF. PMID:28496715

Trends in hospitalization for atrial fibrillation: epidemiology, cost, and implications for the future.

PubMed

Sheikh, Azfar; Patel, Nileshkumar J; Nalluri, Nikhil; Agnihotri, Kanishk; Spagnola, Jonathan; Patel, Aashay; Asti, Deepak; Kanotra, Ritesh; Khan, Hafiz; Savani, Chirag; Arora, Shilpkumar; Patel, Nilay; Thakkar, Badal; Patel, Neil; Pau, Dhaval; Badheka, Apurva O; Deshmukh, Abhishek; Kowalski, Marcin; Viles-Gonzalez, Juan; Paydak, Hakan

2015-01-01

Atrial fibrillation (AF) is the most prevalent arrhythmia worldwide and the most common arrhythmia leading to hospitalization. Due to a substantial increase in incidence and prevalence of AF over the past few decades, it attributes to an extensive economic and public health burden. The increasing number of hospitalizations, aging population, anticoagulation management, and increasing trend for disposition to a skilled facility are drivers of the increasing cost associated with AF. There has been significant progress in AF management with the release of new oral anticoagulants, use of left atrial catheter ablation, and novel techniques for left atrial appendage closure. In this article, we aim to review the trends in epidemiology, hospitalization, and cost of AF along with its future implications on public health. Published by Elsevier Inc.

Remote magnetic navigation in atrial fibrillation.

PubMed

Szili-Torok, Tamas; Akca, Ferdi

2012-05-01

Atrial fibrillation (AF) is of profound public health importance and is largely a disease of aging and is responsible for increased morbidity- and mortality-related healthcare expenditures. Catheter ablation to isolate the pulmonary veins has become the therapy of choice for treatment of drug-refractory AF. Procedures can be very challenging and multiple difficulties must be overcome in order to achieve a successful outcome. The magnetic navigation system (MNS) has advantages in catheter maneuverability, stability and reproducibility. Due to the catheter design safety and efficacy of AF, ablation has increased. New developments are being made to allow fully remote ablation procedures in combination with the MNS. However, new technologies are still necessary to improve MNS ablation for AF.

Left atrial low-voltage areas predict atrial fibrillation recurrence after catheter ablation in patients with paroxysmal atrial fibrillation.

PubMed

Masuda, Masaharu; Fujita, Masashi; Iida, Osamu; Okamoto, Shin; Ishihara, Takayuki; Nanto, Kiyonori; Kanda, Takashi; Tsujimura, Takuya; Matsuda, Yasuhiro; Okuno, Shota; Ohashi, Takuya; Tsuji, Aki; Mano, Toshiaki

2018-04-15

Association between the presence of left atrial low-voltage areas and atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI) has been shown mainly in persistent AF patients. We sought to compare the AF recurrence rate in paroxysmal AF patients with and without left atrial low-voltage areas. This prospective observational study included 147 consecutive patients undergoing initial ablation for paroxysmal AF. Voltage mapping was performed after PVI during sinus rhythm, and low-voltage areas were defined as regions where bipolar peak-to-peak voltage was <0.50mV. Left atrial low-voltage areas after PVI were observed in 22 (15%) patients. Patients with low-voltage areas were significantly older (72±6 vs. 66±10, p<0.0001), more likely to be female (68% vs. 32%, p=0.002), and had higher CHA 2 DS 2 -VASc score (2.5±1.5 vs. 1.8±1.3, p=0.028). During a mean follow-up of 22 (18, 26) months, AF recurrence was observed in 24 (16%) and 16 (11%) patients after the single and multiple ablation procedures, respectively. AF recurrence rate after multiple ablations was higher in patients with low-voltage areas than without (36% vs. 6%, p<0.001). Low-voltage areas were independently associated with AF recurrence even after adjustment for the other related factors (Hazard ratio, 5.89; 95% confidence interval, 2.16 to 16.0, p=0.001). The presence of left atrial low-voltage areas after PVI predicts AF recurrence in patients with paroxysmal AF as well as in patients with persistent AF. Copyright © 2017 Elsevier B.V. All rights reserved.

Mechanisms of Atrial Fibrillation: Rotors, Ionic Determinants and Excitation Frequency

PubMed Central

Berenfeld, Omer; Jalife, José

2017-01-01

Summary Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in humans. However its mechanisms are poorly understood and AF therapy is often sub-optimal. This article reviews recent experimental, numerical and clinical data on dynamics of wave propagation during AF and its mechanistic link to ionic and structural properties of the atria. At the outset, we review numerical and optical mapping data suggesting that the sustained activity of periodic drivers (rotors) with exceedingly high dominant frequencies (DF) of excitation underlies the spatial dispersion and irregularity of activation rates that characterize AF. We show how optical mapping of the fibrillating atria in isolated normal sheep hearts has revealed that the rotors tend to localize in the left atrium (LA). We then discuss exciting new data in the sheep model of tachypacing induced AF demonstrating that the DF of paroxysmal AF episodes increases progressively over days or weeks during the transition to persistent AF (PeAF) and that the rate of the DF increase predicts the onset of PeAF. The data show that the DF increase during the transition may be explained by rotor acceleration secondary to upregulation of IK1 and downregulation of ICaL. The article concludes with a discussion on how translation of experimentally derived knowledge on the behavior and frequency of rotors may find its way into the clinic. We focus on studies in which the analysis of the spatial patterns of DF distribution in the atria of patients with paroxysmal vs persistent has increased our understanding of human AF and how that knowledge might contribute to improve the outcome of AF ablation procedures. PMID:26968663

Atrial Fibrillation and Pulmonary Venous Electrical Conduction Recovery After Full Surgical Resection and Anastomosis of the Pulmonary Veins: Insights From Follow-Up and Ablation Procedures in Lung Transplant Recipients.

PubMed

Hussein, Ayman A; Panchabhai, Tanmay S; Budev, Marie M; Tarakji, Khaldoun; Barakat, Amr F; Saliba, Walid; Lindsay, Bruce; Wazni, Oussama M

2017-06-01

The authors report their experience with atrial fibrillation (AF) rates and ablation findings in lung transplant recipients. Pulmonary venous (PV) conduction recovery accounts for most failed atrial fibrillation (AF) catheter ablation procedures. Lung transplantation involves full surgical resection and replacement of the recipient's PVs with donor's PVs, which may represent the ultimate PV ablation. They followed 755 consecutive lung transplant recipients categorized based on transplant status (unilateral vs. bilateral) and pre-transplant AF. In patients without pre-transplant AF (n = 704), late AF (beyond 6 months after transplant) occurred in 2.5% and 3.3% of unilateral or bilateral lung transplants, respectively. In patients with pre-transplant AF (n = 51), AF recurred in 19.4% and 25.0% of bilateral and unilateral transplants, respectively. In a subset of patients who underwent left atrial ablations after transplant for recurrent refractory AF (n = 8), PV conduction recovery across the surgical anastomoses lines was observed in 22 of 26 previously disconnected PVs. Conduction recovery was observed in ≥1 vein in all but 1 patient. Re-isolation of the veins with additional substrate modification/flutter ablations successfully restored and maintained sinus rhythm in 7 of 8 patients. In lung transplant recipients who undergo full surgical resection of the PVs, a prior history of AF was associated with late AF, regardless of whether patients underwent single or bilateral lung transplantation. PV conduction recovery still occurred and was observed in most patients who underwent left atrial ablation procedures for recurrent AF. Copyright © 2017. Published by Elsevier Inc.

Prospective randomized study to assess the efficacy of site and rate of atrial pacing on long-term progression of atrial fibrillation in sick sinus syndrome: Septal Pacing for Atrial Fibrillation Suppression Evaluation (SAFE) Study.

PubMed

Lau, Chu-Pak; Tachapong, Ngarmukos; Wang, Chun-Chieh; Wang, Jing-Feng; Abe, Haruhiko; Kong, Chi-Woon; Liew, Reginald; Shin, Dong-Gu; Padeletti, Luigi; Kim, You-Ho; Omar, Razali; Jirarojanakorn, Kreingkrai; Kim, Yoon-Nyun; Chen, Mien-Cheng; Sriratanasathavorn, Charn; Munawar, Muhammad; Kam, Ruth; Chen, Jan-Yow; Cho, Yong-Keun; Li, Yi-Gang; Wu, Shu-Lin; Bailleul, Christophe; Tse, Hung-Fat

2013-08-13

Atrial-based pacing is associated with lower risk of atrial fibrillation (AF) in sick sinus syndrome compared with ventricular pacing; nevertheless, the impact of site and rate of atrial pacing on progression of AF remains unclear. We evaluated whether long-term atrial pacing at the right atrial (RA) appendage versus the low RA septum with (ON) or without (OFF) a continuous atrial overdrive pacing algorithm can prevent the development of persistent AF. We randomized 385 patients with paroxysmal AF and sick sinus syndrome in whom a pacemaker was indicated to pacing at RA appendage ON (n=98), RA appendage OFF (n=99), RA septum ON (n=92), or RA septum OFF (n=96). The primary outcome was the occurrence of persistent AF (AF documented at least 7 days apart or need for cardioversion). Demographic data were homogeneous across both pacing site (RA appendage/RA septum) and atrial overdrive pacing (ON/OFF). After a mean follow-up of 3.1 years, persistent AF occurred in 99 patients (25.8%; annual rate of persistent AF, 8.3%). Alternative site pacing at the RA septum versus conventional RA appendage (hazard ratio=1.18; 95% confidence interval, 0.79-1.75; P=0.65) or continuous atrial overdrive pacing ON versus OFF (hazard ratio=1.17; 95% confidence interval, 0.79-1.74; P=0.69) did not prevent the development of persistent AF. In patients with paroxysmal AF and sick sinus syndrome requiring pacemaker implantation, an alternative atrial pacing site at the RA septum or continuous atrial overdrive pacing did not prevent the development of persistent AF. URL: http://www.clinicaltrials.gov. UNIQUE IDENTIFIER: NCT00419640.

Development of a transgenic goat model wih cardiac-specific overexpression of transforming growth factor - {beta} 1 to study the relationship between atrial fibrosis and atrial fibrillation

USDA-ARS?s Scientific Manuscript database

Studies on patients, large animal models and transgenic mouse models have shown a strong association of atrial fibrosis with atrial fibrillation (AF). However, it is unclear whether there is a causal relationship between atrial fibrosis and AF or whether these events appear as a result of independen...

Obesity and Atrial Fibrillation Prevalence, Pathogenesis, and Prognosis: Effects of Weight Loss and Exercise.

PubMed

Lavie, Carl J; Pandey, Ambarish; Lau, Dennis H; Alpert, Martin A; Sanders, Prashanthan

2017-10-17

Both obesity and atrial fibrillation (AF) are increasing in epidemic proportions, and both increase the prevalence of cardiovascular disease events. Obesity has adverse effects on cardiovascular hemodynamics and cardiac structure and function, and increases the prevalence of AF, partly related to electroanatomic remodeling in obese patients. However, numerous studies, including in AF, have demonstrated an obesity paradox, where overweight and obese patients with these disorders have a better prognosis than do leaner patients with the same degree of severity of cardiovascular disease/AF. In this paper, the authors discuss special issues regarding AF in obesity, as well as the evidence that despite the presence of an obesity paradox, there are benefits of weight loss, physical activity/exercise training, and increases in cardiorespiratory fitness on the prognosis of obese patients with AF. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Triggers and Anatomical Substrates in the Genesis and Perpetuation of Atrial Fibrillation

PubMed Central

Sánchez-Quintana, Damián; López-Mínguez, José Ramón; Pizarro, Gonzalo; Murillo, Margarita; Cabrera, José Angel

2012-01-01

The definition of atrial fibrillation (AF) as a functional electrical disorder does not reflect the significant underlying structural abnormalities. Atrial and Pulmonary Vein (PV) muscle sleeve microstructural remodeling is present, and establishes a vulnerable substrate for AF maintenance. In spite of an incomplete understanding of the anatomo-functional basis for AF, current evidence demonstrates that this arrhythmia usually requires a trigger for initiation and a vulnerable electrophysiological and/or anatomical substrate for maintenance. It is still unclear whether the trigger mechanisms include focal enhanced automaticity, triggered activity and/or micro re-entry from myocardial tissue. Initiation of AF can be favored by both parasympathetic and sympathetic stimulation, which also seem to play a role in maintaining AF. Finally, evolving clinical evidence demonstrates that inflammation is associated with new-onset and recurrent AF through a mechanism that possibly involves cellular degeneration, apoptosis, and subsequent atrial fibrosis. PMID:22920484

Improved understanding of the pathophysiology of atrial fibrillation through the lens of discrete pathological pathways

PubMed Central

Balouch, Muhammad A.; Kolek, Matthew J.; Darbar, Dawood

2014-01-01

Atrial fibrillation (AF) is a common disorder with a complex and incompletely understood pathophysiology. Genetic approaches to understanding the pathophysiology of AF have led to the identification of several biological pathways important in the pathogenesis of the arrhythmia. These include pathways important for cardiac development, generation and propagation of atrial electrical impulses, and atrial remodeling and fibrosis. While common and rare genetic variants in these pathways are associated with increased susceptibility to AF, they differ substantially among patients with lone versus typical AF. Furthermore, how these pathways converge to a final common clinical phenotype of AF is unclear and might also vary among different patient populations. Here, we review the contemporary knowledge of AF pathogenesis and discuss how derangement in cardiac development, ion channel dysfunction, and promotion of atrial fibrosis may contribute to this common and important clinical disorder. PMID:25054116

Atrial Fibrillation, Type 2 Diabetes, and Non-Vitamin K Antagonist Oral Anticoagulants: A Review.

PubMed

Plitt, Anna; McGuire, Darren K; Giugliano, Robert P

2017-04-01

Atrial fibrillation (AF) is the most common cardiac arrhythmia and is associated with a 5-fold increase in the risk for stroke. Type 2 diabetes is an independent risk factor for both stroke and atrial fibrillation, and in the setting of AF, type 2 diabetes is independently associated with a 2% to 3.5% increase in absolute stroke rate per year. The overlap in the pathophysiologies of AF and type 2 diabetes are not well understood, and current practice guidelines provide few recommendations regarding patients with both conditions. In this article, we review the epidemiology and pathophysiology of the nexus of AF and type 2 diabetes. Furthermore, we analyze the subgroup of patients with type 2 diabetes enrolled in phase 3 clinical trials of non-vitamin K antagonist oral anticoagulants in prevention of arterial thromboembolism in AF, highlighting the greater absolute benefit of non-vitamin K oral anticoagulants in patients with type 2 diabetes. Finally, we offer recommendations on risk stratification and therapy for patients with concomitant AF and type 2 diabetes. We highlight the increased thromboembolic risk with coexisting AF and type 2 diabetes. We recommend that further studies be done to evaluate the potential benefits of anticoagulation for all patients who have both and the potential for non-vitamin K oral anticoagulants to have greater benefits than risks over vitamin K antagonists.

Identifying postoperative atrial fibrillation in cardiac surgical patients posthospital discharge, using iPhone ECG: a study protocol

PubMed Central

Lowres, Nicole; Freedman, S Ben; Gallagher, Robyn; Kirkness, Ann; Marshman, David; Orchard, Jessica; Neubeck, Lis

2015-01-01

Introduction Postoperative atrial fibrillation (AF) occurs in 30–40% of patients after cardiac surgery. Identification of recurrent postoperative AF is required to initiate evidence-based management to reduce the risk of subsequent stroke. However, as AF is often asymptomatic, recurrences may not be detected after discharge. This study determines feasibility and impact of a self-surveillance programme to identify recurrence of postoperative AF in the month of posthospital discharge. Methods and analysis This is a feasibility study, using a cross-sectional study design, of self-screening for AF using a hand-held single-lead iPhone electrocardiograph device (iECG). Participants will be recruited from the cardiothoracic surgery wards of the Royal North Shore Hospital and North Shore Private Hospital, Sydney, Australia. Cardiac surgery patients admitted in sinus rhythm and experiencing a transient episode of postoperative AF will be eligible for recruitment. Participants will be taught to take daily ECG recordings for 1 month posthospital discharge using the iECG and will be provided education regarding AF, including symptoms and health risks. The primary outcome is the feasibility of patient self-monitoring for AF recurrence using an iECG. Secondary outcomes include proportion of patients identified with recurrent AF; estimation of stroke risk and patient knowledge. Process outcomes and qualitative data related to acceptability of patient's use of the iECG and sustainability of the screening programme beyond the trial setting will also be collected. Ethics and dissemination Primary ethics approval was received on 25 February 2014 from Northern Sydney Local Health District Human Resource Ethics Committee, and on 17 July 2014 from North Shore Private Hospital Ethics Committee. Results will be disseminated via forums including, but not limited to, peer-reviewed publications and presentation at national and international conferences. Trial registration number ACTRN12614000383662. PMID:25586373

Identifying postoperative atrial fibrillation in cardiac surgical patients posthospital discharge, using iPhone ECG: a study protocol.

PubMed

Lowres, Nicole; Freedman, S Ben; Gallagher, Robyn; Kirkness, Ann; Marshman, David; Orchard, Jessica; Neubeck, Lis

2015-01-13

Postoperative atrial fibrillation (AF) occurs in 30-40% of patients after cardiac surgery. Identification of recurrent postoperative AF is required to initiate evidence-based management to reduce the risk of subsequent stroke. However, as AF is often asymptomatic, recurrences may not be detected after discharge. This study determines feasibility and impact of a self-surveillance programme to identify recurrence of postoperative AF in the month of posthospital discharge. This is a feasibility study, using a cross-sectional study design, of self-screening for AF using a hand-held single-lead iPhone electrocardiograph device (iECG). Participants will be recruited from the cardiothoracic surgery wards of the Royal North Shore Hospital and North Shore Private Hospital, Sydney, Australia. Cardiac surgery patients admitted in sinus rhythm and experiencing a transient episode of postoperative AF will be eligible for recruitment. Participants will be taught to take daily ECG recordings for 1 month posthospital discharge using the iECG and will be provided education regarding AF, including symptoms and health risks. The primary outcome is the feasibility of patient self-monitoring for AF recurrence using an iECG. Secondary outcomes include proportion of patients identified with recurrent AF; estimation of stroke risk and patient knowledge. Process outcomes and qualitative data related to acceptability of patient's use of the iECG and sustainability of the screening programme beyond the trial setting will also be collected. Primary ethics approval was received on 25 February 2014 from Northern Sydney Local Health District Human Resource Ethics Committee, and on 17 July 2014 from North Shore Private Hospital Ethics Committee. Results will be disseminated via forums including, but not limited to, peer-reviewed publications and presentation at national and international conferences. ACTRN12614000383662. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Expert consensus of the French Society of Geriatrics and Gerontology and the French Society of Cardiology on the management of atrial fibrillation in elderly people.

PubMed

Hanon, Olivier; Assayag, Patrick; Belmin, Joel; Collet, Jean Philippe; Emeriau, Jean Paul; Fauchier, Laurent; Forette, Françoise; Friocourt, Patrick; Gentric, Armelle; Leclercq, Christophe; Komajda, Michel; Le Heuzey, Jean Yves

2013-05-01

Atrial fibrillation (AF) is a common and serious condition in the elderly. AF affects between 600,000 and one million patients in France, two-thirds of whom are aged above 75 years. AF is a predictive factor for mortality in the elderly and a major risk factor for stroke. Co-morbidities are frequent and worsen the prognosis. The management of AF in the elderly should involve a comprehensive geriatric assessment (CGA), which analyses both medical and psychosocial elements, enabling evaluation of the patient's functional status and social situation and the identification of co-morbidities. The CGA enables the detection of "frailty" using screening tools assessing cognitive function, risk of falls, nutritional status, mood disorders, autonomy and social environment. The objectives of AF treatment in the elderly are to prevent AF complications, particularly stroke, and improve quality of life. Specific precautions for treatment must be taken because of the co-morbidities and age-related changes in pharmacokinetics or pharmacodynamics. Preventing AF complications relies mainly on anticoagulant therapy. Anticoagulants are recommended in patients with AF aged 75 years or above after assessing the bleeding risk using the HEMORR2HAGES or HAS-BLED scores. Novel oral anticoagulants (NOACs) are promising treatments, especially due to a lower risk of intracerebral haemorrhage. However, their prescriptions should take into account renal function (creatinine clearance assessed with Cockcroft formula) and cognitive function (for adherence to treatment). Studies including frail patients in "real life" are necessary to evaluate tolerance of NOACs. Management of AF also involves the treatment of underlying cardiomyopathy and heart rate control rather than a rhythm-control strategy as first-line therapy for elderly patients, especially if they are paucisymptomatic. Antiarrhythmic drugs should be used carefully in elderly patients because of the frequency of metabolic abnormalities and higher risk of drug interactions and bradycardia. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Inhibition of potassium currents is involved in antiarrhythmic effect of moderate ethanol on atrial fibrillation.

PubMed

Yang, Baode; Li, Chenxing; Sun, Junyi; Wang, Xinghui; Liu, Xinling; Yang, Chun; Chen, Lina; Zhou, Jun; Hu, Hao

2017-05-01

Excessive consumption of alcohol is a well-established risk factor of atrial fibrillation (AF). However, the effects of moderate alcohol drinking remain to be elucidated. This study was designed to determine the effects of moderate ethanol ingestion on atrial fibrillation and the electrophysiological mechanisms. In acetylcholine-induced canine and mouse AF models, the moderate ethanol prevented the generation and persistence of AF through prolonging the latent period of AF and shortening the duration of AF. The action potential duration (APD) was remarkably prolonged under the concentration range of 12.5-50.0mM ethanol in guinea pig atrial myocytes. Ultra-rapid delayed rectified potassium currents (I Kv1.5 ) were markedly inhibited by 12.5-50.0mM ethanol in a concentration-dependent manner. Ethanol with 50.0mM could inhibit rapid delayed rectifier potassium currents (I hERG ). Ethanol under 6.25-50.0mM did not affect on inward rectifier potassium currents (I Kir2.1 ). Collectively, the present study provided an evidence that moderate ethanol intake can prolong the APD of atrial myocytes by inhibition of I Kv1.5 and I hERG , which contributed to preventing the development and duration of AF. Copyright © 2017 Elsevier Inc. All rights reserved.

β-Blockers on Discharge From Acute Atrial Fibrillation Are Associated With Decreased Mortality and Lower Cerebrovascular Accidents in Patients With Heart Failure and Reduced Ejection Fraction.

PubMed

Abi Khalil, Charbel; Zubaid, Mohammad; Asaad, Nidal; Rashed, Wafa A; Hamad, Adel Khalifa; Singh, Rajvir; Al Suwaidi, Jassim

2018-04-01

The benefits of β-blockers in patients with heart failure (HF) with reduced ejection fraction (HFrEF) and atrial fibrillation (AF) are controversial. The Gulf Survey of Atrial Fibrillation Events was a prospective, multinational, observational registry of consecutive patients with AF recruited from the emergency department (ED). We studied the incidence of 6- and 12-month mortality, hospitalization for HF or AF, and stroke/transient ischemic attacks (TIAs) in patients with HFrEF, in relation to β-blockers on discharge from the ED or the subsequent hospital stay. Of the 344 patients with HFrEF and AF in the GULF-SAFE, 177 patients (53%) were discharged on β-blockers. Mortality was lower in those patients compared with the non-β-blockers group at 6 and 12 months (odds ratios [ORs] 0.31, 95% CI [0.16-0.61]; OR 0.30, 95% CI [0.16-0.55]; P = .001 for both, respectively), so was the risk of stroke/TIAs. However, hospitalizations for AF increased in the β-blockers group. Even after adjustment for several risk variables in 2 different models, the beneficial effect of β-blockers on mortality persisted, at the cost of more hospitalization for AF.

Catheter ablation in patients with persistent atrial fibrillation

PubMed Central

Kirchhof, Paulus; Calkins, Hugh

2017-01-01

Catheter ablation is increasingly offered to patients who suffer from symptoms due to atrial fibrillation (AF), based on a growing body of evidence illustrating its efficacy compared with antiarrhythmic drug therapy. Approximately one-third of AF ablation procedures are currently performed in patients with persistent or long-standing persistent AF. Here, we review the available information to guide catheter ablation in these more chronic forms of AF. We identify the following principles: Our clinical ability to discriminate paroxysmal and persistent AF is limited. Pulmonary vein isolation is a reasonable and effective first approach for catheter ablation of persistent AF. Other ablation strategies are being developed and need to be properly evaluated in controlled, multicentre trials. Treatment of concomitant conditions promoting recurrent AF by life style interventions and medical therapy should be a routine adjunct to catheter ablation of persistent AF. Early rhythm control therapy has a biological rationale and trials evaluating its value are underway. There is a clear need to generate more evidence for the best approach to ablation of persistent AF beyond pulmonary vein isolation in the form of adequately powered controlled multi-centre trials. PMID:27389907

[Structural and functional changes of myocardium in Chernobyl disaster clean-up workers with atrial fibrillation].

PubMed

Khomaziuk, I M; Habulavichene, Zh M; Khomaziuk, V A

2011-01-01

Particularities and clinical importance of the structural and functional changes of myocardium were estimated in Chernobyl disaster clean-up workers with atrial fibrillation (AF). We examined 122 men with AF, which was associated with ischemic heart disease and arterial hypertension. Paroxysmal AF was diagnosed in 42 patients, 80 patients had permanent AE Control group comprised 80 men without AF. Echocardiography and Doppler studies were performed using ultrasound scanner Aloka SSD-630 (Japan). Significant structural and functional changes of the heart were revealed already in paroxysmal AF and became more pronounced in permanent AF. Increased left atrial size, its ratio to left ventricular end diastolic diameter, diastolic dysfunction were important echocardiographic predictors of AF. Heart walls thickening was accompanied by disorders of myocardial relaxation, increase in myocardial mass led to ischemia, and together they promoted overload, dysfunction of atrium and development of AF. Obligatory echocardiographic examination of the Chernobyl disaster clean-up workers with ischemic heart disease and arterial hypertension is necessary for predicting AF early, ordering adequate therapy in proper time and improving prognosis.

Higher risk of death and stroke in patients with persistent vs. paroxysmal atrial fibrillation: results from the ROCKET-AF Trial.

PubMed

Steinberg, Benjamin A; Hellkamp, Anne S; Lokhnygina, Yuliya; Patel, Manesh R; Breithardt, Günter; Hankey, Graeme J; Becker, Richard C; Singer, Daniel E; Halperin, Jonathan L; Hacke, Werner; Nessel, Christopher C; Berkowitz, Scott D; Mahaffey, Kenneth W; Fox, Keith A A; Califf, Robert M; Piccini, Jonathan P

2015-02-01

Anticoagulation prophylaxis for stroke is recommended for at-risk patients with either persistent or paroxysmal atrial fibrillation (AF). We compared outcomes in patients with persistent vs. paroxysmal AF receiving oral anticoagulation. Patients randomized in the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared With Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET-AF) trial (n = 14 264) were grouped by baseline AF category: paroxysmal or persistent. Multivariable adjustment was performed to compare thrombo-embolic events, bleeding, and death between groups, in high-risk subgroups, and across treatment assignment (rivaroxaban or warfarin). Of 14 062 patients, 11 548 (82%) had persistent AF and 2514 (18%) had paroxysmal AF. Patients with persistent AF were marginally older (73 vs. 72, P = 0.03), less likely female (39 vs. 45%, P < 0.0001), and more likely to have previously used vitamin K antagonists (64 vs. 56%, P < 0.0001) compared with patients with paroxysmal AF. In patients randomized to warfarin, time in therapeutic range was similar (58 vs. 57%, P = 0.94). Patients with persistent AF had higher adjusted rates of stroke or systemic embolism (2.18 vs. 1.73 events per 100-patient-years, P = 0.048) and all-cause mortality (4.78 vs. 3.52, P = 0.006). Rates of major bleeding were similar (3.55 vs. 3.31, P = 0.77). Rates of stroke or systemic embolism in both types of AF did not differ by treatment assignment (rivaroxaban vs. warfarin, Pinteraction = 0.6). In patients with AF at moderate-to-high risk of stroke receiving anticoagulation, those with persistent AF have a higher risk of thrombo-embolic events and worse survival compared with paroxysmal AF. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Cardiology.

Mobile Health Technology for Atrial Fibrillation Management Integrating Decision Support, Education, and Patient Involvement: mAF App Trial.

PubMed

Guo, Yutao; Chen, Yundai; Lane, Deirdre A; Liu, Lihong; Wang, Yutang; Lip, Gregory Y H

2017-12-01

Mobile Health technology for the management of patients with atrial fibrillation is unknown. The simple mobile AF (mAF) App was designed to incorporate clinical decision-support tools (CHA 2 DS 2 -VASc [Congestive heart failure, Hypertension, Age ≥75 years, Diabetes Mellitus, Prior Stroke or TIA, Vascular disease, Age 65-74 years, Sex category], HAS-BLED [Hypertension, Abnormal renal/liver function, Stroke, Bleeding history or predisposition, Labile INR, Elderly, Drugs/alcohol concomitantly], SAMe-TT 2 R 2 [Sex, Age <60 years, Medical history, Treatment, Tobacco use, Race] scores), educational materials, and patient involvement strategies with self-care protocols and structured follow-up. Patients with atrial fibrillation were randomized into 2 groups (mAF App vs usual care) in a cluster randomized design pilot study. Patients' knowledge, quality of life, drug adherence, and anticoagulation satisfaction were evaluated at baseline, 1 month, and 3 months. Usability, feasibility, and acceptability of the mAF App were assessed at 1 month. A total of 113 patients were randomized to mAF App intervention (mean age, 67.4 years; 57.5% were male; mean follow-up, 69 days), and 96 patients were randomized to usual care (mean age, 70.9 years; 55.2% were male; mean follow-up, 95 days). More than 90% of patients reported that the mAF App was easy, user-friendly, helpful, and associated with significant improvements in knowledge compared with the usual care arm (P values for trend <.05). Drug adherence and anticoagulant satisfaction were significantly better with the mAF App versus usual care (all P < .05). Quality of life scores were significantly increased in the mAF App arm versus usual care, with anxiety and depression reduced (all P < .05). The pilot mAFA Trial is the first prospective randomized trial of Mobile Health technology in patients with atrial fibrillation, demonstrating that the mAF App, integrating clinical decision support, education, and patient-involvement strategies, significantly improved knowledge, drug adherence, quality of life, and anticoagulation satisfaction. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Validation of a new simple scale to measure symptoms in atrial fibrillation: the Canadian Cardiovascular Society Severity in Atrial Fibrillation scale.

PubMed

Dorian, Paul; Guerra, Peter G; Kerr, Charles R; O'Donnell, Suzan S; Crystal, Eugene; Gillis, Anne M; Mitchell, L Brent; Roy, Denis; Skanes, Allan C; Rose, M Sarah; Wyse, D George

2009-06-01

Atrial fibrillation (AF) is commonly associated with impaired quality of life. There is no simple validated scale to quantify the functional illness burden of AF. The Canadian Cardiovascular Society Severity in Atrial Fibrillation (CCS-SAF) scale is a bedside scale that ranges from class 0 to 4, from no effect on functional quality of life to a severe effect on life quality. This study was performed to validate the scale. In 484 patients with documented AF (62.2+/-12.5 years of age, 67% men; 62% paroxysmal and 38% persistent/permanent), the SAF class was assessed and 2 validated quality-of-life questionnaires were administered: the SF-36 generic scale and the disease-specific AFSS (University of Toronto Atrial Fibrillation Severity Scale). There is a significant linear graded correlation between the SAF class and measures of symptom severity, physical and emotional components of quality of life, general well-being, and health care consumption related to AF. Patients with SAF class 0 had age- and sex-standardized SF-36 scores of 0.15+/-0.16 and -0.04+/-0.31 (SD units), that is, units away from the mean population score for the mental and physical summary scores, respectively. For each unit increase in SAF class, there is a 0.36 and 0.40 SD unit decrease in the SF-36 score for the physical and mental components. As the SAF class increases from 0 to 4, the symptom severity score (range, 0 to 35) increases from 4.2+/-5.0 to 18.4+/-7.8 (P<0.0001). The CCS-SAF scale is a simple semiquantitative scale that closely approximates patient-reported subjective measures of quality of life in AF and may be practical for clinical use.

Atrial Fibrillation During an Exploration Class Mission

NASA Technical Reports Server (NTRS)

Lipset, Mark A.; Lemery, Jay; Polk, J. D.; Hamilton, Douglas R.

2010-01-01

Background: A long-duration exploration class mission is fraught with numerous medical contingency plans. Herein, we explore the challenges of symptomatic atrial fibrillation (AF) occurring during an exploration class mission. The actions and resources required to ameliorate the situation, including the availability of appropriate pharmaceuticals, monitoring devices, treatment modalities, and communication protocols will be investigated. Challenges of Atrial Fibrillation during an Exploration Mission: Numerous etiologies are responsible for the initiation of AF. On Earth, we have the time and medical resources to evaluate and determine the causative situation for most cases of AF and initiate therapy accordingly. During a long-duration exploration class mission resources will be severely restricted. How is one to determine if new onset AF is due to recent myocardial infarction, pulmonary embolism, fluid overload, thyrotoxicosis, cardiac structural abnormalities, or CO poisoning? Which pharmaceutical therapy should be initiated and what potential side effects can be expected? Should anti-coagulation therapy be initiated? How would one monitor the therapeutic treatment of AF in microgravity? What training would medical officers require, and which communication strategies should be developed to enable the best, safest therapeutic options for treatment of AF during a long-duration exploration class mission? Summary: These questions will be investigated with expert opinion on disease elucidation, efficient pharmacology, therapeutic monitoring, telecommunication strategies, and mission cost parameters with emphasis on atrial fibrillation being just one illustration of the tremendous challenges that face a long-duration exploration mission. The limited crew training time, medical hardware, and drugs manifested to deal with such an event predicate that aggressive primary and secondary prevention strategies be developed to protect a multibillion-dollar asset like the International Space Station or a mission to the Moon or Mars. Learning Objectives: The audience will become familiar with the risks and challenges inherent to developing a therapeutic strategy for the treatment of atrial fibrillation during a long-term exploration class mission.

[Electrophysiological findings and ablation strategies in patients with atrial tachyarrhythmias after left atrial circumferential ablation in the treatment of atrial fibrillation].

PubMed

Chen, Ming-long; Yang, Bing; Xu, Dong-jie; Zou, Jian-gang; Shan, Qi-jun; Chen, Chun; Chen, Hong-wu; Li, Wen-qi; Cao, Ke-jiang

2007-02-01

To report the electrophysiological findings and the ablation strategies in patients with atrial tachyarrhythmias (ATAs) or atrial fibrillation (AF) recurrence after left atrial circumferential ablation (LACA) in the treatment of AF. 91 patients with AF had LACA procedure from April 2004 to May 2006, 19 of which accepted the second ablation procedure due to ATAs or AF recurrence. In all the 19 patients [17 male, 2 female, age 25 - 65 (53 +/- 12) years], 11 presented with paroxysmal AF before the first ablation procedure, 2 with persistent AF and 6 with permanent AF. Pulmonary vein potentials (PVP) were investigated in both sides in all the patients. Delayed PVP was identified inside the left circular line in 5 patients, in the right in 1 and both in 2 during sinus rhythm. "Gap" conduction was found and successfully closed guided by circular mapping catheter. In 3 cases, irregular left atrial tachycardia was caused by fibrillation rhythm inside the left ring via decremental "gap" conduction. Reisolation was done successfully again guided by 3-D mapping and made the left atrium in sinus rhythm but the fibrillation rhythm was still inside the left ring. Pulmonary vein tachycardia with 1:1 conduction to the left atrium presented in one case and reisolation stopped the tachycardia. No PVP was discovered in both sides in 4 patients but other tachycardias could be induced, including two right atrial scar related tachycardias, two supraventricular tachycardias mediated by concealed accessory pathway, one cavo-tricuspid isthmus dependent atrial flutter and one focal atrial tachycardia near the coronary sinus ostium. All the tachycardias in these 4 patients were successfully ablated with the help of routine and 3-D mapping techniques. In the rest 3, which were in AF rhythm, LACA was successfully done again. After a mean follow-up of 4 - 26 (11.5 +/- 8.5) months, 16 patients were symptom free without anti-arrhythmic drug therapy; 1 of them had frequent palpitation attack with Holter recording of atrial premature contractions; 2 of them with permanent AF became paroxysmal in one, and still in AF in the other. Reconduction between the left atrium and the pulmonary veins is the dominant factor for post-LACA ATAs and AF recurrence. Other forms of atrial tachycardias or supraventricular tachycardias may coexist with AF or sometimes trigger AF. LACA can not sufficiently modify AF substrate in some permanent AF patients.

Flecainide-metoprolol combination reduces atrial fibrillation clinical recurrences and improves tolerability at 1-year follow-up in persistent symptomatic atrial fibrillation.

PubMed

Capucci, Alessandro; Piangerelli, Luca; Ricciotti, Jenny; Gabrielli, Domenico; Guerra, Federico

2016-11-01

Atrial fibrillation (AF) affects ∼2% of the total population. In order to prevent AF recurrences, many anti-arrhythmic drugs are currently available, but most of them are burdened by serious side effects and suboptimal efficacy. The aim of the present study was to test efficacy and safety of a combination of flecainide and metoprolol in preventing AF clinical recurrences. This study is a monocentric, prospective, randomized, open-blinded trial on 173 patients with a recent episode of paroxysmal or persistent AF. Patients were randomized into group A (flecainide + metoprolol; n = 80), group B (flecainide only; n = 72), or group C (metoprolol only; n = 21). Main exclusion criteria were recent acute coronary syndrome, heart failure New York Heart Association class III-IV, left ventricular ejection fraction <0.40, atrioventricular conduction disorders, and severe bradycardia. Primary endpoint was symptomatic recurrence over 1-year follow-up. Secondary endpoint was quality of life (QoL) over 1-year follow-up, as assessed by the SF-36 and Atrial Fibrillation Severity Scale questionnaires. Combination therapy with flecainide and metoprolol significantly reduced recurrences at 1-year follow-up when compared with flecainide alone in the whole population (66.7 vs. 46.8%; P < 0.001) and in patients with persistent AF (71.1 vs. 43.6%; P = 0.025) while adding beta-blocker therapy to paroxysmal AF showed no benefit over IC anti-arrhythmic drug-only. Patients randomized to combination therapy experienced a significant improvement of QoL when compared with those assigned to a flecainide-only regimen irrespective of AF type. Flecainide-metoprolol combination therapy improves effectiveness of rhythm control in persistent symptomatic AF and increases tolerability, with a concomitant reduction of side effects and a better compliance. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

Use of self-gated radial cardiovascular magnetic resonance to detect and classify arrhythmias (atrial fibrillation and premature ventricular contraction).

PubMed

Piekarski, Eve; Chitiboi, Teodora; Ramb, Rebecca; Feng, Li; Axel, Leon

2016-11-25

Arrhythmia can significantly alter the image quality of cardiovascular magnetic resonance (CMR); automatic detection and sorting of the most frequent types of arrhythmias during the CMR acquisition could potentially improve image quality. New CMR techniques, such as non-Cartesian CMR, can allow self-gating: from cardiac motion-related signal changes, we can detect cardiac cycles without an electrocardiogram. We can further use this data to obtain a surrogate for RR intervals (valley intervals: VV). Our purpose was to evaluate the feasibility of an automated method for classification of non-arrhythmic (NA) (regular cycles) and arrhythmic patients (A) (irregular cycles), and for sorting of common arrhythmia patterns between atrial fibrillation (AF) and premature ventricular contraction (PVC), using the cardiac motion-related signal obtained during self-gated free-breathing radial cardiac cine CMR with compressed sensing reconstruction (XD-GRASP). One hundred eleven patients underwent cardiac XD-GRASP CMR between October 2015 and February 2016; 33 were included for retrospective analysis with the proposed method (6 AF, 8 PVC, 19 NA; by recent ECG). We analyzed the VV, using pooled statistics (histograms) and sequential analysis (Poincaré plots), including the median (medVV), the weighted mean (meanVV), the total number of VV values (VVval), and the total range (VVTR) and half range (VVHR) of the cumulative frequency distribution of VV, including the median to half range (medVV/VVHR) and the half range to total range (VVHR/VVTR) ratios. We designed a simple algorithm for using the VV results to differentiate A from NA, and AF from PVC. Between NA and A, meanVV, VVval, VVTR, VVHR, medVV/VVHR and VVHR/VVTR ratios were significantly different (p values = 0.00014, 0.0027, 0.000028, 5×10 -9 , 0.002, respectively). Between AF and PVC, meanVV, VVval and medVV/VVHR ratio were significantly different (p values = 0.018, 0.007, 0.044, respectively). Using our algorithm, sensitivity, specificity, and accuracy were 93 %, 95 % and 94 % to discriminate between NA and A, and 83 %, 71 %, and 77 % to discriminate between AF and PVC, respectively; areas under the ROC curve were 0.93 and 0.89. Our study shows we can reliably detect arrhythmias and differentiate AF from PVC, using self-gated cardiac cine XD-GRASP CMR.

Performance of handheld electrocardiogram devices to detect atrial fibrillation in a cardiology and geriatric ward setting.

PubMed

Desteghe, Lien; Raymaekers, Zina; Lutin, Mark; Vijgen, Johan; Dilling-Boer, Dagmara; Koopman, Pieter; Schurmans, Joris; Vanduynhoven, Philippe; Dendale, Paul; Heidbuchel, Hein

2017-01-01

To determine the usability, accuracy, and cost-effectiveness of two handheld single-lead electrocardiogram (ECG) devices for atrial fibrillation (AF) screening in a hospital population with an increased risk for AF. Hospitalized patients (n = 445) at cardiological or geriatric wards were screened for AF by two handheld ECG devices (MyDiagnostick and AliveCor). The performance of the automated algorithm of each device was evaluated against a full 12-lead or 6-lead ECG recording. All ECGs and monitor tracings were also independently reviewed in a blinded fashion by two electrophysiologists. Time investments by nurses and physicians were tracked and used to estimate cost-effectiveness of different screening strategies. Handheld recordings were not possible in 7 and 21.4% of cardiology and geriatric patients, respectively, because they were not able to hold the devices properly. Even after the exclusion of patients with an implanted device, sensitivity and specificity of the automated algorithms were suboptimal (Cardiology: 81.8 and 94.2%, respectively, for MyDiagnostick; 54.5 and 97.5%, respectively, for AliveCor; Geriatrics: 89.5 and 95.7%, respectively, for MyDiagnostick; 78.9 and 97.9%, respectively, for AliveCor). A scenario based on automated AliveCor evaluation in patients without AF history and without an implanted device proved to be the most cost-effective method, with a provider cost to identify one new AF patient of €193 and €82 at cardiology and geriatrics, respectively. The cost to detect one preventable stroke per year would be €7535 and €1916, respectively (based on average CHA 2 DS 2 -VASc of 3.9 ± 2.0 and 5.0 ± 1.5, respectively). Manual interpretation increases sensitivity, but decreases specificity, doubling the cost per detected patient, but remains cheaper than sole 12-lead ECG screening. Using AliveCor or MyDiagnostick handheld recorders requires a structured screening strategy to be effective and cost-effective in a hospital setting. It must exclude patients with implanted devices and known AF, and requires targeted additional 12-lead ECGs to optimize specificity. Under these circumstances, the expenses per diagnosed new AF patient and preventable stroke are reasonable. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

QUest for the Arrhythmogenic Substrate of Atrial fibRillation in Patients Undergoing Cardiac Surgery (QUASAR Study): Rationale and Design.

PubMed

van der Does, Lisette J M E; Yaksh, Ameeta; Kik, Charles; Knops, Paul; Lanters, Eva A H; Teuwen, Christophe P; Oei, Frans B S; van de Woestijne, Pieter C; Bekkers, Jos A; Bogers, Ad J J C; Allessie, Maurits A; de Groot, Natasja M S

2016-06-01

The heterogeneous presentation and progression of atrial fibrillation (AF) implicate the existence of different pathophysiological processes. Individualized diagnosis and therapy of the arrhythmogenic substrate underlying AF may be required to improve treatment outcomes. Therefore, this single-center study aims to identify the arrhythmogenic areas underlying AF by intra-operative, high-resolution, multi-site epicardial mapping in 600 patients with different heart diseases. Participants are divided into 12 groups according to the underlying heart diseases and presence of prior AF episodes. Mapping is performed with a 192-electrode array for 5-10 s during sinus rhythm and (induced) AF of the entire atrial surface. Local activation times are converted into activation and wave maps from which various electrophysiological parameters are derived. Postoperative cardiac rhythm registrations and a 5-year follow-up will show the incidence of postoperative and persistent AF. This project provides the first step in the development of a tool for individual AF diagnosis and treatment.

Role of Rotors in the Ablative Therapy of Persistent Atrial Fibrillation

PubMed Central

Schricker, Amir A; Zaman, Junaid; Narayan, Sanjiv M

2015-01-01

Atrial fibrillation (AF) ablation is increasingly used to maintain sinus rhythm yet its results are sub-optimal, especially in patients with persistent AF or prior unsuccessful procedures. Attempts at improvement have often targeted substrates that sustain AF after it is triggered, yet those mechanisms are debated. Many studies now challenge the concept that AF is driven by self-sustaining disordered wavelets, showing instead that localised drivers (rotors) may drive disorder via a process known as fibrillatory conduction. Novel mapping using wide-area recordings, physiological filtering and phase analysis demonstrates rotors in human AF. Contact mapping with focal impulse and rotor modulation (FIRM) shows that localised ablation at sources can improve procedural success in many populations on long-term follow up and some newer approaches to rotor mapping are qualitatively similar. This review critically evaluates the data on rotor mapping and ablation, which advances our conceptual understanding of AF and holds the promise of substantially improving ablative outcomes in patients with persistent AF. PMID:26835100

Minimally Invasive Delivery of Hydrogel-Encapsulated Amiodarone to the Epicardium Reduces Atrial Fibrillation.

PubMed

Garcia, Jose R; Campbell, Peter F; Kumar, Gautam; Langberg, Jonathan J; Cesar, Liliana; Deppen, Juline N; Shin, Eric Y; Bhatia, Neal K; Wang, Lanfang; Xu, Kai; Schneider, Frank; Robinson, Brian; García, Andrés J; Levit, Rebecca D

2018-05-01

Atrial fibrillation (AF) is the most common cardiac arrhythmia. Although treatment options for AF exist, many patients cannot be maintained in normal sinus rhythm. Amiodarone is an effective medication for AF but has limited clinical utility because of off-target tissue toxicity. Here, we use a pig model of AF to test the efficacy of an amiodarone-containing polyethylene glycol-based hydrogel. The gel is placed directly on the atrial epicardium through the pericardial space in a minimally invasive procedure using a specially designed catheter. Implantation of amiodarone-containing gel significantly reduced the duration of sustained AF at 21 and 28 days; inducibility of AF was reduced 14 and 21 days post-delivery. Off-target organ drug levels in the liver, lungs, thyroid, and fat were significantly reduced in animals treated with epicardial amiodarone gel compared with systemic controls in small-animal distribution studies. The pericardium is an underutilized therapeutic site and may be a new treatment strategy for AF and other cardiovascular diseases. © 2018 American Heart Association, Inc.

[Atrial fibrillation in elderly].

PubMed

Arquizan, Caroline

2012-11-01

Atrial fibrilation (AF) is frequent and a strong risk factor for ischemic stroke in elderly. Ischemic stroke in patients with AF are more severe. Vitamine K antagonist therapy is highly effective for stroke prevention but is associated with hemorrhagic risk. The new oral anticoagulants (direct thrombin inhibitor [dabigatran], and direct factor Xa inhibitors [rivaroxaban and apixaban]) have all shown non inferiority or superiority, with better safety, considering the risk of intracranial haemorrhage. On this basis, it is justified to give them in priority in the vast majority of patients with AF, the choice of the drug and the dose is individual.

Contemporary stroke prevention strategies in 11 096 European patients with atrial fibrillation: a report from the EURObservational Research Programme on Atrial Fibrillation (EORP-AF) Long-Term General Registry.

PubMed

Boriani, Giuseppe; Proietti, Marco; Laroche, Cécile; Fauchier, Laurent; Marin, Francisco; Nabauer, Michael; Potpara, Tatjana; Dan, Gheorghe-Andrei; Kalarus, Zbigniew; Diemberger, Igor; Tavazzi, Luigi; Maggioni, Aldo P; Lip, Gregory Y H

2018-05-01

Contemporary data regarding atrial fibrillation (AF) management and current use of oral anticoagulants (OACs) for stroke prevention are needed. The EURObservational Research Programme on AF (EORP-AF) Long-Term General Registry analysed consecutive AF patients presenting to cardiologists in 250 centres from 27 European countries. From 2013 to 2016, 11 096 patients were enrolled (40.7% female; mean age 69 ± 11 years). At discharge, OACs were used in 9379 patients (84.9%), with non-vitamin K antagonists (NOACs) accounting for 40.9% of OACs. Antiplatelet therapy alone was used by 20% of patients, while no antithrombotic treatment was prescribed in 6.4%. On multivariable analysis, age, hypertension, previous ischaemic stroke, symptomatic AF and planned cardioversion or ablation were independent predictors of OAC use, whereas lone AF, previous haemorrhagic events, chronic kidney disease and admission for acute coronary syndrome (ACS) or non-cardiovascular causes independently predicted OAC non-use. Regarding the OAC type, coronary artery disease, history of heart failure, or valvular heart disease, planned cardioversion and non-AF reasons for admission independently predicted the use of vitamin K antagonists (VKAs). Wide variability among the European regions was observed in the use of NOACs, independently from other clinical factors. The EORP-AF Long-Term General Registry provides a full picture of contemporary use of OAC in European AF patients. The overall rate of OACs use was generally high (84.9%), and a series of factors were associated with the prescription of OAC. A significant geographical heterogeneity in prescription of NOACs vs. VKAs was evident.

Prognostic implications of atrial fibrillation in patients undergoing myocardial perfusion single-photon emission computed tomography.

PubMed

Abidov, Aiden; Hachamovitch, Rory; Rozanski, Alan; Hayes, Sean W; Santos, Marcia M; Sciammarella, Maria G; Cohen, Ishac; Gerlach, James; Friedman, John D; Germano, Guido; Berman, Daniel S

2004-09-01

The aim of this research was to determine whether presence of atrial fibrillation (AF) provides incremental prognostic information relative to myocardial perfusion single-photon emission computed tomography (MPS) with respect to risk of cardiac death (CD). The prognostic significance of AF in patients undergoing MPS is not known. A total of 16,048 consecutive patients undergoing MPS were followed-up for a mean of 2.21 +/- 1.15 years for the development of CD. Of those, 384 patients (2.4%) had AF. Cox proportional hazards method was used to compare clinical and perfusion data for the prediction of CD in patients with and without AF. Atrial fibrillation was a significant predictor of CD in patients with normal (1.6% per year vs. 0.4% per year in non-AF patients), mildly abnormal (6.3% per year vs. 1.2% per year), and severely abnormal MPS (6.4% per year vs. 3.7% per year) (p < 0.001 for all). By multivariable analysis, AF patients had worse survival (p = 0.001) even after adjustment for the variables most predictive of CD: age, diabetes, shortness of breath, use of vasodilator stress, rest heart rate, and the nuclear variables. In the 4,239 patients with left ventricular ejection fraction evaluated by gated MPS, AF demonstrated incremental prognostic value not only over clinical and nuclear variables, but also over left ventricular ejection in predicting CD (p = 0.014). The presence of AF independently increases the risk of cardiac events over perfusion and function variables in patients undergoing MPS. Patients with AF have a high risk of CD, even when MPS is only mildly abnormal. Whether patients with AF and mildly abnormal MPS constitute a group more deserving of early referral to cardiac catheterization is a question warranting further study.

Atrial rhythm influences catheter tissue contact during radiofrequency catheter ablation of atrial fibrillation: comparison of contact force between sinus rhythm and atrial fibrillation.

PubMed

Matsuda, Hisao; Parwani, Abdul Shokor; Attanasio, Philipp; Huemer, Martin; Wutzler, Alexander; Blaschke, Florian; Haverkamp, Wilhelm; Boldt, Leif-Hendrik

2016-09-01

Catheter tissue contact force (CF) is an important factor for durable lesion formation during radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF). Since CF varies in the beating heart, atrial rhythm during RFCA may influence CF. A high-density map and RFCA points were obtained in 25 patients undergoing RFCA of AF using a CF-sensing catheter (Tacticath, St. Jude Medical). The operators were blinded to the CF information. Contact type was classified into three categories: constant, variable, and intermittent contact. Average CF and contact type were analyzed according to atrial rhythm (SR vs. AF) and anatomical location. A total of 1364 points (891 points during SR and 473 points during AF) were analyzed. Average CFs showed no significant difference between SR (17.2 ± 11.3 g) and AF (17.2 ± 13.3 g; p = 0.99). The distribution of points with an average CF of ≥20 and <10 g also showed no significant difference. However, the distribution of excessive CF (CF ≥40 g) was significantly higher during AF (7.4 %) in comparison with SR (4.2 %; p < 0.05). At the anterior area of the right inferior pulmonary vein (RIPV), the average CF during AF was significantly higher than during SR (p < 0.05). Constant contact was significantly higher during AF (32.2 %) when compared to SR (9.9 %; p < 0.01). Although the average CF was not different between atrial rhythms, constant contact was more often achievable during AF than it was during SR. However, excessive CF also seems to occur more frequently during AF especially at the anterior part of RIPV.

Achieving Bidirectional Long Delays In Pulmonary Vein Antral Lines Prior To Bidirectional Block In Patients With Paroxysmal Atrial Fibrillation (The Bi-Bi Technique For Atrial Fibrillation Ablation).

PubMed

Mina, Adel F; Warnecke, Nicholas L

2016-01-01

Background: Pulmonary Vein Antral isolation (PVAI) is currently the standard of care for both paroxysmal and persistent atrial fibrillation ablation. Reconnection to the pulmonary vein is the most common cause of recurrence of atrial fibrillation. Achieving the endpoint of bidirectional block (BDB) for cavotricuspid isthmus dependant flutter has improved our outcomes for atrial flutter ablation. With this we tried to achieve long delays in the pulmonary veins antral lines prior to complete isolation comparable to those delays found in patient with bidirectional block of atrial flutter lines. Study Objective: The objective of this paper was to evaluate feasibility and efficacy of achieving Bidirectional long delays in pulmonary vein antral lines prior to Bidirectional Block in patient with paroxysmal atrial fibrillation. Method: A retrospective analysis was performed on patients who had paroxysmal atrial fibrillation procedures at Unity Point Methodist from January 2015 to January 2016. 20 consecutive patients with paroxysmal atrial fibrillation who had AF ablation using the Bi-Bi technique were evaluated. Result: Mean age was 63, number of antiarrhythmic used prior to ablation was 1.4, mean left atrial size was 38 mm. Mean chads score was 1.3. Mean EF was 53%. Long delays in the left antral circumferential lines were achieved with mean delay of 142 milliseconds +/-100. Also long delays in the right antral circumferential lines were achieved with mean delay of 150 milliseconds +/-80. 95 % (19/20) of patients were free of any atrial arrhythmias and were off antiarrhythmic medications for AF post procedure. There was only one transient complication in one patient who developed a moderate pericardial effusion that was successfully drained with no hemodynamic changes. The only patient who had recurrence was found to have asymptomatic AF with burden on his device <1%, this patient was also found to have non PV triggers for his AF. In patients with only PV triggered AF success rate was 100%. Conclusion: Achievement of Bidirectional long delays in pulmonary vein antral lines prior to Bidirectional Block in patient with paroxysmal atrial fibrillation is feasible and highly effective technique in this small cohort of patients studied. We also outlined the procedure in details.

3 Tesla MRI-detected brain lesions after pulmonary vein isolation for atrial fibrillation: results of the MACPAF study.

PubMed

Haeusler, Karl Georg; Koch, Lydia; Herm, Juliane; Kopp, Ute A; Heuschmann, Peter U; Endres, Matthias; Schultheiss, Heinz-Peter; Schirdewan, Alexander; Fiebach, Jochen B

2013-01-01

Left atrial catheter ablation (LACA) is an established therapeutic approach to abolish symptomatic atrial fibrillation (AF). Based on the prospective MACPAF study (clinicaltrials.gov NCT01061931) we report the rate of ischemic brain lesions postablation and their impact on cognitive function. Patients with symptomatic paroxysmal AF were randomized to LACA using the Arctic Front® or the HD Mesh Ablator® catheter. All patients underwent brain MRI at 3 Tesla, neurological, and neuropsychological examinations within 48 hours prior and after the ablation procedure. There was no clinically evident stroke in 37 patients (mean age 62.4 ± 8.4 years; 41% female; median CHADS2 score 1 [IQR 0-2]) after LACA but high-resolution diffusion-weighted imaging (DWI) detected new ischemic lesions in 15 (41%) patients after LACA. Four (27%) of the HD Mesh Ablator® patients and 11 (50%) of the Arctic Front® patients suffered a silent ischemic lesion (P = 0.19). In these 15 patients, there was a nonsignificant trend toward lower cardiac ejection fraction (P = 0.07) and AF episodes during LACA (P = 0.09), while activated clotting time levels, number of energy applications, periprocedural electrocardioversion or CHADS(2) score had no impact. Lesion volumes varied from 5 to 150 mm(3) and 1 to 5 lesions were detected per patient. However, acute brain lesions had no effect on cognitive performance immediately after LACA. Of the DWI lesions postablation 82% were not detectable on FLAIR images 6-9 months postablation. According to 3 Tesla high-resolution DWI, ischemic brain lesions after LACA were common but not associated with impaired cognitive function after the ablation procedure. © 2012 Wiley Periodicals, Inc.

Atrial fibrillation in the Middle East: unmapped, underdiagnosed, undertreated.

PubMed

Al-Shamkhani, Warkaa; Ayetey, Harold; Lip, Gregory Y H

2018-05-01

Atrial fibrillation (AF) is the commonest persistent cardiac arrhythmia with an estimated incidence rate of between 1.5-2% and an important cause of strokes. Few epidemiological studies and clinical trials on the management of AF have been conducted outside Europe and North America. These gaps in our understanding of AF likely lead to sub-optimal management of patients with AF in the rest of the world. Areas covered: We discuss the epidemiology, treatment and clinical outcomes for AF in the Middle East after systematic review of published work for AF from the Middle East. We also discuss important clinical trials on AF conducted in the West in the same period to help contextualize our findings. Expert commentary: The few available Middle East studies suggest important epidemiological differences between Middle Eastern and Western AF populations. In particular, the Middle Eastern AF population is younger and have more co-morbidities than patients in the West. We find that significant numbers of moderate to high risk patients with AF are either undertreated or untreated placing them at increased risk of complications such as stroke. More studies in the Middle Eastern population are required to aid the development of region-specific clinical guidelines to improve patient care.

Management of recent-onset sustained atrial fibrillation: pharmacologic and nonpharmacologic strategies.

PubMed

Lau, Dennis H; Kalman, Jonathan; Sanders, Prashanthan

2014-09-01

Recent studies have highlighted significant variations in the management of recent-onset sustained atrial fibrillation (AF). We aim to provide a succinct and clear management algorithm for physicians treating patients with recent-onset sustained AF. We performed a comprehensive search of the literature on the management of recent-onset sustained AF with focus on studies reporting cardioversion of AF, antiarrhythmic agents, and anticoagulation. We also reviewed recent practice guidelines on AF management. This review provides a guide on a tailored management approach of patients with recent-onset sustained AF. After initial detailed clinical assessment, optimal rate and rhythm control options can be provided, depending on hemodynamic stability, duration of AF episode, and AF stroke risk. Issues surrounding electrical and pharmacologic cardioversion are discussed in detail. We emphasize the importance of thromboembolic risk assessment and appropriate anticoagulation surrounding the point of cardioversion. Last, we highlighted the need for appropriate specialized follow-up care after acute AF management. Despite the highly heterogeneous clinical presentations, management of recent-onset sustained AF must include stroke risk assessment, appropriate anticoagulation, and follow-up care in all patients beyond optimum rate and rhythm control strategies. Copyright © 2014. Published by Elsevier Inc.

Atrial Fibrillation in Hematologic Malignancies, Especially After Autologous Hematopoietic Stem Cell Transplantation: Review of Risk Factors, Current Management, and Future Directions.

PubMed

Mathur, Pankaj; Paydak, Hakan; Thanendrarajan, Sharmilan; van Rhee, Frits

2016-02-01

Atrial fibrillation (AF) is the most common cardiac arrhythmia and is associated with significant morbidity and mortality worldwide. In addition to well-established risk factors, cancer has been increasingly associated with the development of AF. Its increased occurrence in those with hematologic malignancies has been attributed to chemotherapeutic agents and autologous hematopoietic stem cell transplantation (AHSCT). Recently, a few studies have attempted to define the etiopathogenesis of AF in hematologic malignancies. The management of AF in these patients is challenging because of the concurrent complicating factors, such as thrombocytopenia, orthostatic hypotension, and cardiac amyloidosis. More studies are needed to define the management of AF, especially rate versus rhythm control and anticoagulation. Arrhythmias, in particular, AF, have been associated with an increased length of stay, increased intensive care unit admissions, and greater cardiovascular mortality. In the present review, we describe AF in patients with hematologic malignancies, the risk factors, especially after AHSCT, and the current management of AF. Copyright © 2016 Elsevier Inc. All rights reserved.

Predicting termination of atrial fibrillation based on the structure and quantification of the recurrence plot.

PubMed

Sun, Rongrong; Wang, Yuanyuan

2008-11-01

Predicting the spontaneous termination of the atrial fibrillation (AF) leads to not only better understanding of mechanisms of the arrhythmia but also the improved treatment of the sustained AF. A novel method is proposed to characterize the AF based on structure and the quantification of the recurrence plot (RP) to predict the termination of the AF. The RP of the electrocardiogram (ECG) signal is firstly obtained and eleven features are extracted to characterize its three basic patterns. Then the sequential forward search (SFS) algorithm and Davies-Bouldin criterion are utilized to select the feature subset which can predict the AF termination effectively. Finally, the multilayer perceptron (MLP) neural network is applied to predict the AF termination. An AF database which includes one training set and two testing sets (A and B) of Holter ECG recordings is studied. Experiment results show that 97% of testing set A and 95% of testing set B are correctly classified. It demonstrates that this algorithm has the ability to predict the spontaneous termination of the AF effectively.

Nurse-led clinics for atrial fibrillation: managing risk factors.

PubMed

Jacob, Liril

2017-12-14

Atrial fibrillation (AF) is the most common and sustained cardiac arrhythmia rated by cardiologists as one of the most difficult conditions to manage. Traditionally, AF management has focused on the three pillars of rate control, rhythm control and anticoagulation. However, more recently, cardiovascular risk-factor management in AF has emerged as a fourth and essential pillar, delivering improved patient outcomes. In the UK, AF is a condition that is often managed poorly, with patients reporting a lack of understanding of their condition and treatment options. Many aspects of assessment and communication in AF management are time consuming. Failure to address those aspects may negatively affect the quality of care. Nurse-led clinics can contribute significantly in the areas of patient education and sustained follow-up care, improving outcomes and addressing current deficiencies in AF risk-factor management due to scarcity of medical resources. This article discusses the major cardiovascular risk factors associated with AF, drawing on evidence from the literature, and considers the effectiveness and implications for practice of introducing community-based nurse-led clinics for risk-factor management in patients with AF.

Association of a Family History of Atrial Fibrillation With Incidence and Outcomes of Atrial Fibrillation: A Population-Based Family Cohort Study.

PubMed

Chang, Shang-Hung; Kuo, Chang-Fu; Chou, I-Jun; See, Lai-Chu; Yu, Kuang-Hui; Luo, Shue-Fen; Huang, Lu-Hsiang; Zhang, Weiya; Doherty, Michael; Wen, Ming-Shien; Kuo, Chi-Tai; Yeh, Yung-Hsin

2017-08-01

The heritability of atrial fibrillation (AF), the contribution of genetic and environmental factors, and the association of a family history of AF with prognosis are unclear. To measure genetic and environmental factors in the familial aggregation of AF and to estimate the association of a family history of AF with major adverse cardiovascular events (MACE). In this Taiwanese nationwide population-based study among more than 23 million people, a custom data set was obtained using the data of all patients having a diagnosis of AF recorded between January 1996 and December 2013 in the Taiwan National Health Insurance Research Database. The study population comprised all 23 422 955 individuals registered with the database in 2013, of whom 177 770 had a diagnosis of AF and were included in the heritability estimation. From the latter, a subgroup of patients having newly diagnosed AF with a first-degree relative affected by AF between 2000 and 2010 were selected and matched 1:4 to controls without a family history for estimating MACE-free survival. The dates of analysis were January 2010 to December 2013. The prevalence and relative risk of AF in relatives of patients with AF, as well as the relative contributions of heritability and shared and nonshared environmental factors to AF susceptibility. Also measured was MACE-free survival after AF was diagnosed. In total, 1510 patients (204 [13.5%] female; mean [SD] age, 57.9 [9.2] years) had newly diagnosed AF with a first-degree relative affected by AF. Individuals with a first-degree relative affected by AF had a relative risk of 1.92 (95% CI, 1.84-1.99) for AF. The accountability for the phenotypic variance of AF was 19.9% for genetic factors (heritability), 3.5% for shared environmental factors, and 76.6% for nonshared environmental factors. After matching for age, sex, hypertension, type 2 diabetes, previous stroke, and anticoagulation, incident AF patients with vs without an affected first-degree relative had similar MACE-free survival. Genetic and environmental factors were associated with AF, with nonshared environmental factors accounting for three-fourths of the phenotypic variance in Taiwan. Patients having AF with a first-degree relative affected by AF did not have more MACE. Therefore, family history may not be particularly informative in the diagnosis or management of AF.

Ablating Atrial Fibrillation: Customizing Lesion Sets Guided by Rotor Mapping

PubMed Central

Zaman, Junaid A. B.; Narayan, Sanjiv M.

2015-01-01

Ablation occupies an increasing role in the contemporary management of atrial fibrillation (AF), but results are suboptimal, particularly for persistent AF. While an anatomic approach to ablation is a highly efficacious and safe method to isolate pulmonary vein (PV) triggers, recurrence of AF is not always associated with PV reconnection, and there is compelling evidence that non-PV sites sustain AF after it is triggered. Recent developments in wide-area mapping and signal processing now identify rotors in the vast majority of AF patients that sustain AF and whose elimination improves long-term freedom from AF in multicenter studies. Investigators have now demonstrated rotor and focal sources for AF that show many analogous properties between approaches: they lie in spatially reproducible regions temporally over hours to days, and they are amenable to targeted ablation. This review outlines the rationale and technical developments supporting this mechanistic paradigm for human AF, and discusses how rotor mapping may be implemented for individual patient customization of lesion sets. Mechanistic studies are required to explain why rotor elimination (or other ablation approaches) producing long-term elimination of AF may not always terminate AF acutely, how AF correlates with structural changes on magnetic resonance imaging, and how these findings can be integrated clinically with current ablation strategies to improve patient outcomes. PMID:26306123

Ablating Atrial Fibrillation: Customizing Lesion Sets Guided by Rotor Mapping.

PubMed

Zaman, Junaid A B; Narayan, Sanjiv M

2015-01-01

Ablation occupies an increasing role in the contemporary management of atrial fibrillation (AF), but results are suboptimal, particularly for persistent AF. While an anatomic approach to ablation is a highly efficacious and safe method to isolate pulmonary vein (PV) triggers, recurrence of AF is not always associated with PV reconnection, and there is compelling evidence that non-PV sites sustain AF after it is triggered. Recent developments in wide-area mapping and signal processing now identify rotors in the vast majority of AF patients that sustain AF and whose elimination improves long-term freedom from AF in multicenter studies. Investigators have now demonstrated rotor and focal sources for AF that show many analogous properties between approaches: they lie in spatially reproducible regions temporally over hours to days, and they are amenable to targeted ablation. This review outlines the rationale and technical developments supporting this mechanistic paradigm for human AF, and discusses how rotor mapping may be implemented for individual patient customization of lesion sets. Mechanistic studies are required to explain why rotor elimination (or other ablation approaches) producing long-term elimination of AF may not always terminate AF acutely, how AF correlates with structural changes on magnetic resonance imaging, and how these findings can be integrated clinically with current ablation strategies to improve patient outcomes.

A Prospective Survey of Atrial Fibrillation Management for Real-world Guideline Adherence: COmparison study of Drugs for symptom control and complication prEvention of Atrial Fibrillation (CODE-AF) Registry.

PubMed

Kim, Hyeongsoo; Kim, Tae Hoon; Cha, Myung Jin; Lee, Jung Myung; Park, Junbeom; Park, Jin Kyu; Kang, Ki Woon; Shim, Jaemin; Uhm, Jae Sun; Kim, Jun; Park, Hyung Wook; Choi, Eue Keun; Kim, Jin Bae; Kim, Changsoo; Lee, Young Soo; Joung, Boyoung

2017-11-01

The aging population is rapidly increasing, and atrial fibrillation (AF) is becoming a significant public health burden in Asia, including Korea. This study evaluated current treatment patterns and guideline adherence of AF treatment. In a prospective observational registry (COmparison study of Drugs for symptom control and complication prEvention of Atrial Fibrillation [CODE-AF] registry), 6,275 patients with nonvalvular AF were consecutively enrolled between June 2016 and April 2017 from 10 tertiary hospitals in Korea. The AF type was paroxysmal, persistent, and permanent in 65.3%, 30.0%, and 2.9% of patients, respectively. Underlying structural heart disease was present in 11.9%. Mean CHA₂DS₂-VASc was 2.7±1.7. Oral anticoagulation (OAC), rate control, and rhythm control were used in 70.1%, 53.9%, and 54.4% of patients, respectively. OAC was performed in 82.7% of patients with a high stroke risk. However, antithrombotic therapy was inadequately used in 53.4% of patients with a low stroke risk. For rate control in 192 patients with low ejection fraction (<40%), β-blocker (65.6%), digoxin (5.2%), or both (19.3%) were adequately used in 90.1% of patients; however, a calcium channel blocker was inadequately used in 9.9%. A rhythm control strategy was chosen in 54.4% of patients. The prescribing rate of class Ic antiarrythmics, dronedarone, and sotalol was 16.9% of patients with low ejection fraction. This study shows how successfully guidelines can be applied in the real world. The nonadherence rate was 17.2%, 9.9%, and 22.4% for stroke prevention, rate control, and rhythm control, respectively. Copyright © 2017. The Korean Society of Cardiology

Sleep-Disordered Breathing and Excessive Daytime Sleepiness in Patients With Atrial Fibrillation

PubMed Central

Albuquerque, Felipe N.; Calvin, Andrew D.; Sert Kuniyoshi, Fatima H.; Konecny, Tomas; Lopez-Jimenez, Francisco; Pressman, Gregg S.; Kara, Thomas; Friedman, Paul; Ammash, Naser; Somers, Virend K.

2012-01-01

Background: An important consequence of sleep-disordered breathing (SDB) is excessive daytime sleepiness (EDS). EDS often predicts a favorable response to treatment of SDB, although in the setting of cardiovascular disease, particularly heart failure, SDB and EDS do not reliably correlate. Atrial fibrillation (AF) is another highly prevalent condition strongly associated with SDB. We sought to assess the relationship between EDS and SDB in patients with AF. Methods: We conducted a prospective study of 151 patients referred for direct current cardioversion for AF who also underwent sleep evaluation and nocturnal polysomnography. The Epworth Sleepiness Scale (ESS) was administered prior to polysomnography and considered positive if the score was ≥ 11. The apnea-hypopnea index (AHI) was tested for correlation with the ESS, with a cutoff of ≥ 5 events/h for the diagnosis of SDB. Results: Among the study participants, mean age was 69.1 ± 11.7 years, mean BMI was 34.1 ± 8.4 kg/m2, and 76% were men. The prevalence of SDB in this population was 81.4%, and 35% had EDS. The association between ESS score and AHI was low (R2 = 0.014, P = .64). The sensitivity and specificity of the ESS for the detection of SDB in patients with AF were 32.2% and 54.5%, respectively. Conclusions: Despite a high prevalence of SDB in this population with AF, most patients do not report EDS. Furthermore, EDS does not appear to correlate with severity of SDB or to accurately predict the presence of SDB. Further research is needed to determine whether EDS affects the natural history of AF or modifies the response to SDB treatment. PMID:21903736

Left atrial strain and strain rate in patients with paroxysmal and persistent atrial fibrillation: relationship to left atrial structural remodeling detected by delayed-enhancement MRI.

PubMed

Kuppahally, Suman S; Akoum, Nazem; Burgon, Nathan S; Badger, Troy J; Kholmovski, Eugene G; Vijayakumar, Sathya; Rao, Swati N; Blauer, Joshua; Fish, Eric N; Dibella, Edward V R; Macleod, Rob S; McGann, Christopher; Litwin, Sheldon E; Marrouche, Nassir F

2010-05-01

Atrial fibrillation (AF) is a progressive condition that begins with hemodynamic and/or structural changes in the left atrium (LA) and evolves through paroxysmal and persistent stages. Because of limitations with current noninvasive imaging techniques, the relationship between LA structure and function is not well understood. Sixty-five patients (age, 61.2+/-14.2 years; 67% men) with paroxysmal (44%) or persistent (56%) AF underwent 3D delayed-enhancement MRI. Segmentation of the LA wall was performed and degree of enhancement (fibrosis) was determined using a semiautomated quantification algorithm. Two-dimensional echocardiography and longitudinal LA strain and strain rate during ventricular systole with velocity vector imaging were obtained. Mean fibrosis was 17.8+/-14.5%. Log-transformed fibrosis values correlated inversely with LA midlateral strain (r=-0.5, P=0.003) and strain rate (r=-0.4, P<0.005). Patients with persistent AF as compared with paroxysmal AF had more fibrosis (22+/-17% versus 14+/-9%, P=0.04) and lower midseptal (27+/-14% versus 38+/-16%, P=0.01) and midlateral (35+/-16% versus 45+/-14% P=0.03) strains. Multivariable stepwise regression showed that midlateral strain (r=-0.5, P=0.006) and strain rate (r=-0.4, P=0.01) inversely predicted the extent of fibrosis independent of other echocardiographic parameters and the rhythm during imaging. LA wall fibrosis by delayed-enhancement MRI is inversely related to LA strain and strain rate, and these are related to the AF burden. Echocardiographic assessment of LA structural and functional remodeling is quick and feasible and may be helpful in predicting outcomes in AF.

Imaging before cryoablation of atrial fibrillation: is phrenic nerve palsy predictable?

PubMed

Canpolat, Uğur; Aytemir, Kudret; Hızal, Mustafa; Hazırolan, Tuncay; Yorgun, Hikmet; Sahiner, Levent; Kaya, Ergun Barış; Oto, Ali

2014-04-01

Multidetector computerized tomography (MDCT) with improved temporal and spatial resolution is one of the most commonly used non-invasive tests for evaluation of pulmonary veins (PVs) and adjacent structures before cryoablation of atrial fibrillation (AF). Identification of spatial neighbouring of phrenic nerves is important to decrease likelihood of phrenic nerve palsy (PNP). The purpose of our study is to clarify the course of right phrenic nerve, its relations to PVs using 64-slice MDCT, and effect on occurrence of PNP. A total of 162 patients underwent MDCT with 3D reconstruction of left atrium prior to cryoablation for AF. The location of the right pericardiophrenic artery (RPA) was identified on axial images and artery distance to the right upper PV (RUPV) ostium was measured in 3D image. Right pericardiophrenic artery was detectable in 145 of 162 (89.5%) patients (52.4% male, age 54.5 ± 10.1 years, and 80.7% paroxysmal AF). Acute procedural success rate was 96.2%. Mean procedural and fluoroscopy times were 74.4 ± 6.2 and 15.7 ± 4.3 min. Transient right PNP was developed in four (2.75%) patients. RUPV ostium to RPA distance was lower in patients with PNP (P = 0.033). In multivariate regression analysis, only RUPV ostium to RPA distance (odds ratio: 2.95; 95% confidence interval: 1.76-4.66, P = 0.001) was the independent predictor of PNP occurrence during cryoablation. Our results revealed that pre-ablation cardiac imaging with 64-slice MDCT adequately detected RPA bordering the phrenic nerve, which was an important determinant of PNP development during cryoballoon-based AF ablation.

Growth differentiation factor 15 is associated with left atrial/left atrial appendage thrombus in patients with nonvalvular atrial fibrillation.

PubMed

Hu, Xiao Feng; Zhan, Rui; Xu, Shanhu; Wang, Junjun; Wu, Jiong; Liu, Xiaoli; Li, Yaguo; Chen, Linhui

2018-01-01

There is evidence suggesting that growth differentiation factor 15 (GDF-15) appears to be associated with stroke in patients with atrial fibrillation (AF). AF-related thromboembolic stroke is predominantly attributed to the thrombus from the left atrium (LA) or left atrial appendage (LAA). GDF-15 is related to LA/LAA thrombus in nonvalvular AF (NVAF) patients. A total of 894 patients with NVAF without anticoagulation therapy were included in this study. All patients routinely underwent transesophageal echocardiography for detection of LA/LAA thrombus. GDF-15 was measured by enzyme-linked immunosorbent assay. Logistic regression models were used to test for association. LA/LAA thrombus was detected by transesophageal echocardiography in 69 (7.72%) patients with AF. The GDF-15 levels in the patients with LA/LAA thrombus were significantly higher than those without LA/LAA thrombus (log 10 GDF-15: 2.989 ± 0.023 ng/L vs 2.831 ± 0.007 ng/L; P < 0.001). Logistic regression analysis showed that GDF-15 was an independent risk factor for LA/LAA thrombus (odds ratio [per quarter]: 1.799, 95% confidence interval: 1.381-2.344, P < 0.001) after adjusting for potential clinical risk factors. The optimal cutoff point for GDF-15 predicting LA/LAA thrombus was 809.9 ng/L (sensitivity, 75.3%; specificity, 61.5%), determined by ROC curve. The area under the curve was 0.709 (95% confidence interval: 0.644-0.770, P < 0.001). Elevated GDF-15 indicated a significantly increased risk for LA/LAA thrombus in NVAF patients. Thus, GDF-15 might be a potentially useful adjunct in discriminating LA/LAA thrombus in NVAF patients. © 2018 Wiley Periodicals, Inc.

Inhibition of potassium currents is involved in antiarrhythmic effect of moderate ethanol on atrial fibrillation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Baode; Li, Chenxing

Excessive consumption of alcohol is a well-established risk factor of atrial fibrillation (AF). However, the effects of moderate alcohol drinking remain to be elucidated. This study was designed to determine the effects of moderate ethanol ingestion on atrial fibrillation and the electrophysiological mechanisms. In acetylcholine-induced canine and mouse AF models, the moderate ethanol prevented the generation and persistence of AF through prolonging the latent period of AF and shortening the duration of AF. The action potential duration (APD) was remarkably prolonged under the concentration range of 12.5–50.0 mM ethanol in guinea pig atrial myocytes. Ultra-rapid delayed rectified potassium currents (I{submore » Kv1.5}) were markedly inhibited by 12.5–50.0 mM ethanol in a concentration-dependent manner. Ethanol with 50.0 mM could inhibit rapid delayed rectifier potassium currents (I{sub hERG}). Ethanol under 6.25–50.0 mM did not affect on inward rectifier potassium currents (I{sub Kir2.1}). Collectively, the present study provided an evidence that moderate ethanol intake can prolong the APD of atrial myocytes by inhibition of I{sub Kv1.5} and I{sub hERG}, which contributed to preventing the development and duration of AF. - Highlights: • Moderate ethanol prevented the development of AF in animal models. • Moderate ethanol prolonged APD in guinea pig atrial myocytes. • Moderate ethanol inhibited Kv1.5 currents.« less

The Current Role of Omega-3 Fatty Acids in the Management of Atrial Fibrillation.

PubMed

Christou, Georgios A; Christou, Konstantinos A; Korantzopoulos, Panagiotis; Rizos, Evangelos C; Nikas, Dimitrios N; Goudevenos, John A

2015-09-22

The main dietary source of omega-3 polyunsaturated fatty acids (n-3 PUFA) is fish, which contains eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). In the present manuscript, we aimed to review the current evidence regarding the clinical role of n-3 PUFA in the prevention of atrial fibrillation (AF) and the possible underlying mechanisms. A literature search based on PubMed listings was performed using "Omega-3 fatty acids" and "atrial fibrilation" as key search terms. n-3 PUFA have been shown to attenuate structural atrial remodeling, prolong atrial effective refractory period through the prevention of reentry and suppress ectopic firing from pulmonary veins. Dietary fish intake has been found to have no effect on the incidence of AF in the majority of studies. Circulating DHA has been consistently reported to be inversely associated with AF risk, whereas EPA has no such effect. The majority of studies investigating the impact of n-3 PUFA supplementation on the incidence of AF following cardiac surgery reported no benefit, though most of them did not use n-3 PUFA pretreatment for adequate duration. Studies using adequate four-week pretreatment with n-3 PUFA before cardioversion of AF showed a reduction of the AF incidence. Although n-3 PUFA have antiarrhythmogenic properties, their clinical efficacy on the prevention of AF is not consistently supported. Further well-designed studies are needed to overcome the limitations of the existing studies and provide robust conclusions.

Women hospitalized with atrial fibrillation: gender differences, trends and outcome from a 20-year registry in a Middle Eastern country (1991-2010).

PubMed

Salam, Amar M; AlBinali, Hajar A; Al-Mulla, Abdul Wahid; Asaad, Nidal; Singh, Rajvir; Al-Qahtani, Awad; Al Suwaidi, Jassim

2013-09-30

Most of the published research on atrial fibrillation (AF) is limited to studies in the developed world and included mainly Caucasian patients. Data about women with AF among other ethnicities is very limited. The aim of this study was to compare the clinical characteristics, treatment and outcome of women to men hospitalized with AF in a middle-eastern country. Retrospective analysis of prospective registry of all patients hospitalized with AF in Qatar from 1991 through 2010 was made. Clinical characteristics, management, and outcomes of AF patients were compared according to gender. During the 20-years period; 1417 women and 2432 men were hospitalized for AF. Women were 5 years older and more likely to have diabetes mellitus, hypertension, and chronic renal impairment and were also less likely to be current smokers and to have ischemic heart disease and impaired left ventricular function when compared to men. There was no gender preference in the use of anticoagulation. The prevalence of concomitant ischemic heart disease and hypertension increased, while the prevalence of valvular heart disease and heart failure decreased among patients hospitalized with AF over the study period. In-hospital mortality and stroke rates were comparable between the two groups. Women hospitalized with atrial fibrillation were older in age and had higher prevalence of co-morbid cardiovascular risk factors compared to men whereas, mortality and stroke rates were comparable. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Rationale and design of the Atrial Fibrillation health Literacy Information Technology Trial: (AF-LITT).

PubMed

Guhl, Emily N; Schlusser, Courtney L; Henault, Lori E; Bickmore, Timothy W; Kimani, Everlyne; Paasche-Orlow, Michael K; Magnani, Jared W

2017-11-01

Atrial Fibrillation (AF) is a common cardiac arrhythmia that is challenging for patients and adversely impacts health-related quality of life (HRQoL). Long-term management of AF requires that patients adhere to complex therapies, understand difficult terminology, navigate subspecialty care, and have continued symptom monitoring with the goal of preventing adverse outcomes. Continued interventions to ameliorate the patient experience of AF are essential. The Atrial Fibrillation health Literacy Information Technology Trial (AF-LITT; NCT03093558) is an investigator-initiated, 2-arm randomized clinical trial (RCT). This RCT is a pilot in order to implement a novel, smartphone-based intervention to address the patient experience of AF. This pilot RCT will compare a combination of the Embodied Conversational Agent (ECA) and the Alive Cor Kardia Mobile heart rhythm monitor to the current standard of care. The study will enroll 180 adults with non-valvular AF who are receiving anticoagulation for stroke prevention and randomize them to receive a 30-day intervention (smartphone-based ECA/Kardia) or standard of care, which will include a symptom and adherence journal. The primary end-points are improvement in HRQoL and self-reported adherence to anticoagulation. The secondary end-points are the acceptability of the intervention to participants, its use by participants, and acceptability to referring physicians. The AF-LITT pilot aims to evaluate the efficacy of the ECA/Kardia to improve HRQoL and anticoagulant adherence, and to guide its implementation in a larger, multicenter clinical trial. The intervention has potential to improve HRQoL, adherence, and health care utilization in individuals with chronic AF. Copyright © 2017 Elsevier Inc. All rights reserved.

Rationale and design of the Atrial Fibrillation health Literacy Information Technology Trial: (AF-LITT)

PubMed Central

Guhl, Emily N.; Schlusser, Courtney L.; Henault, Lori E.; Bickmore, Timothy W.; Kimani, Everlyne; Paasche-Orlow, Michael K.; Magnani, Jared W.

2017-01-01

Background Atrial Fibrillation (AF) is a common cardiac arrhythmia that is challenging for patients and adversely impacts health-related quality of life (HRQoL). Long-term management of AF requires that patients adhere to complex therapies, understand difficult terminology, navigate subspecialty care, and have continued symptom monitoring with the goal of preventing adverse outcomes. Continued interventions to ameliorate the patient experience of AF are essential. Design The Atrial Fibrillation health Literacy Information Technology Trial (AF-LITT; NCT03093558) is an investigator-initiated, 2-arm randomized clinical trial (RCT). This RCT is a pilot in order to implement a novel, smartphone-based intervention to address the patient experience of AF. This pilot RCT will compare a combination of the embodied conversational agent (ECA) and the Alive Cor Kardia Mobile heart rhythm monitor to the current standard of care. The study will enroll 180 adults with non-valvular AF who are receiving anticoagulation for stroke prevention and randomize them to receive a 30-day intervention (smartphone-based ECA/Kardia) or standard of care, which will include a symptom and adherence journal. The primary end-points are improvement in HRQoL and self-reported adherence to anticoagulation. The secondary end-points are the acceptability of the intervention to participants, its use by participants, and acceptability to referring physicians. Conclusions The AF-LITT pilot aims to evaluate the efficacy of the ECA/Kardia to improve HRQoL and anticoagulant adherence, and to guide its implementation in a larger, multicenter clinical trial. The intervention has potential to improve HRQoL, adherence, and health care utilization in individuals with chronic AF. PMID:28923492

ECG Based Heart Arrhythmia Detection Using Wavelet Coherence and Bat Algorithm

NASA Astrophysics Data System (ADS)

Kora, Padmavathi; Sri Rama Krishna, K.

2016-12-01

Atrial fibrillation (AF) is a type of heart abnormality, during the AF electrical discharges in the atrium are rapid, results in abnormal heart beat. The morphology of ECG changes due to the abnormalities in the heart. This paper consists of three major steps for the detection of heart diseases: signal pre-processing, feature extraction and classification. Feature extraction is the key process in detecting the heart abnormality. Most of the ECG detection systems depend on the time domain features for cardiac signal classification. In this paper we proposed a wavelet coherence (WTC) technique for ECG signal analysis. The WTC calculates the similarity between two waveforms in frequency domain. Parameters extracted from WTC function is used as the features of the ECG signal. These features are optimized using Bat algorithm. The Levenberg Marquardt neural network classifier is used to classify the optimized features. The performance of the classifier can be improved with the optimized features.

Effect of the Epicardial Adipose Tissue Volume on the Prevalence of Paroxysmal and Persistent Atrial Fibrillation.

PubMed

Oba, Kageyuki; Maeda, Minetaka; Maimaituxun, Gulinu; Yamaguchi, Satoshi; Arasaki, Osamu; Fukuda, Daiju; Yagi, Shusuke; Hirata, Yukina; Nishio, Susumu; Iwase, Takashi; Takao, Shoichiro; Kusunose, Kenya; Yamada, Hirotsugu; Soeki, Takeshi; Wakatsuki, Tetsuzo; Harada, Masafumi; Masuzaki, Hiroaki; Sata, Masataka; Shimabukuro, Michio

2018-05-25

Although increasing evidence suggests that epicardial adipose tissue volume (EATV) is associated with atrial fibrillation (AF), it is controversial whether there is a dose-response relationship of increasing EATV along the continuum of AF. We evaluated the effect of the EATV on the prevalence of paroxysmal AF (PAF) and persistent AF (PeAF) and the relationships with cardiac structure and functional remodeling.Methods and Results:Subjects who underwent multidetector computed tomography (MDCT) coronary angiography because of symptoms suggestive of coronary artery disease were divided into sinus rhythm (SR) (n=112), PAF (n=133), and PeAF (n=71) groups. The EATV index (EATV/body surface area, mL/m 2 ) was strongly associated with the prevalence of PAF and PeAF on the model adjusted for known AF risk factors. The effect of the EATV index on the prevalence of PeAF, but not on that of PAF, was modified by the left atrial (LA) dimension, suggesting that extension of the LA dimension is related to EATV expansion in PeAF. The cutoff value of the EATV index for the prevalence was higher in PeAF than in PAF (64 vs. 55 mL/m 2 , P<0.01). The EATV index is associated with the prevalence of PAF and PeAF, and its cutoff values are predictive for PAF and PeAF development independently of other AF risk factors.

Increased expression of NF-AT3 and NF-AT4 in the atria correlates with procollagen I carboxyl terminal peptide and TGF-β1 levels in serum of patients with atrial fibrillation.

PubMed

Zhao, Fei; Zhang, ShiJiang; Chen, YiJiang; Gu, WeiDong; Ni, BuQing; Shao, YongFeng; Wu, YanHu; Qin, JianWei

2014-11-25

Atrial fibrillation (AF) is the most common cardiac arrhythmia in clinical practice. Unfortunately, the precise mechanisms and sensitive serum biomarkers of atrial remodeling in AF remain unclear. The aim of this study was to determine whether the expression of the transcription factors NF-AT3 and NF-AT4 correlate with atrial structural remodeling of atrial fibrillation and serum markers for collagen I and III synthesis. Right and left atrial specimens were obtained from 90 patients undergoing valve replacement surgery. The patients were divided into sinus rhythm (n = 30), paroxysmal atrial fibrillation (n = 30), and persistent atrial fibrillation (n = 30) groups. NF-AT3, NF-AT4, and collagen I and III mRNA and protein expression in atria were measured. We also tested the levels of the carboxyl-terminal peptide from pro-collagen I, the N-terminal type I procollagen propeptides, the N-terminal type III procollagen propeptides, and TGF-β1 in serum using an enzyme immunosorbent assay. NF-AT3 and NF-AT4 mRNA and protein expression were increased in the AF groups, especially in the left atrium. NF-AT3 and NF-AT4 expression in the right atrium was increased in the persistent atrial fibrillation group compared the sinus rhythm group with similar valvular disease. In patients with AF, the expression levels of nuclear NF-AT3 and NF-AT4 correlated with those of collagens I and III in the atria and with PICP and TGF-β1 in blood. These data support the hypothesis that nuclear NF-AT3 and NF-AT4 participates in atrial structural remodeling, and that PICP and TGF-β1 levels may be sensitive serum biomarkers to estimate atrial structural remodeling with atrial fibrillation.

Electrogram Morphology Recurrence Patterns during Atrial Fibrillation

PubMed Central

Ng, Jason; Gordon, David; Passman, Rod S.; Knight, Bradley P.; Arora, Rishi; Goldberger, Jeffrey J.

2014-01-01

Background Traditional mapping of atrial fibrillation (AF) is limited by changing electrogram morphologies and variable cycle lengths. Objective We tested the hypothesis that morphology recurrence plot analysis would identify sites of stable and repeatable electrogram morphology patterns. Methods AF electrograms recorded from left atrial (LA) and right atrial (RA) sites in 19 patients (10 male, 59±10 years old) prior to AF ablation were analyzed. Morphology recurrence plots for each electrogram recording were created by cross-correlation of each automatically detected activation with every other activation in the recording. A recurrence percentage, the percentage of the most common morphology, and the mean cycle length of activations with the most common morphology (CLR) were computed. Results The morphology recurrence plots commonly showed checkerboard patterns of alternating high and low cross correlation values indicating periodic recurrences in morphologies. The mean recurrence percentage for all sites and all patients was 38±25%. The highest recurrence percentage per patient averaged 83±17%. The highest recurrence percentage was located in the RA in 5 patients and in the LA in 14 patients. Patients with sites of shortest CLR in the LA and RA had ablation failure rates of 25% and 100%, respectively (HR=4.95; p=0.05). Conclusions A new technique to characterize electrogram morphology recurrence demonstrated that there is a distribution of sites with high and low repeatability of electrogram morphologies. Sites with rapid activation of highly repetitive morphology patterns may be critical to sustaining AF. Further testing of this approach to map and ablate AF sources is warranted. PMID:25101485

Presence and stability of rotors in atrial fibrillation: evidence and therapeutic implications

PubMed Central

Guillem, María S.; Climent, Andreu M.; Rodrigo, Miguel; Fernández-Avilés, Francisco; Atienza, Felipe; Berenfeld, Omer

2016-01-01

Rotor-guided ablation has opened new perspectives into the therapy of atrial fibrillation (AF). Analysis of the spatio-temporal cardiac excitation patterns in the frequency and phase domains has demonstrated the importance of rotors in research models of AF, however, the dynamics and role of rotors in human AF are still controversial. In this review, the current knowledge gained through research models and patient data that support the notion that rotors are key players in AF maintenance is summarized. We report and discuss discrepancies regarding rotor prevalence and stability in various studies, which can be attributed in part to methodological differences among mapping systems. Future research for validation and improvement of current clinical electrophysiology mapping technologies will be crucial for developing mechanistic-based selection and application of the best therapeutic strategy for individual AF patient, being it, pharmaceutical, ablative, or other approach. PMID:26786157

The role of rotors in atrial fibrillation

PubMed Central

Swarup, Vijay; Narayan, Sanjiv M.

2015-01-01

Despite significant advances in our understanding of atrial fibrillation (AF) mechanisms in the last 15 years, ablation outcomes remain suboptimal. A potential reason is that many ablation techniques focus on anatomic, rather than patient-specific functional targets for ablation. Panoramic contact mapping, incorporating phase analysis, repolarization and conduction dynamics, and oscillations in AF rate, overcomes many prior difficulties with mapping AF. This approach provides evidence that the mechanisms sustaining human AF are deterministic, largely due to stable electrical rotors and focal sources in either atrium. Ablation of such sources (Focal Impulse and Rotor Modulation: FIRM ablation) has been shown to improve ablation outcome compared with conventional ablation alone; independent laboratories directly targeting stable rotors have shown similar results. Clinical trials examining the role of stand-alone FIRM ablation are in progress. Looking forward, translating insights from patient-specific mapping to evidence-based guidelines and clinical practice is the next challenge in improving patient outcomes in AF management. PMID:25713729

Impact of aldosterone antagonists on the substrate for atrial fibrillation: Aldosterone promotes oxidative stress and atrial structural/electrical remodeling

PubMed Central

Mayyas, Fadia; Alzoubi, Karem H.; Van Wagoner, David R.

2014-01-01

Atrial fibrillation (AF), the most common cardiac arrhythmia, is an electrocardiographic description of a condition with multiple and complex underlying mechanisms. Oxidative stress is an important driver of structural remodeling that creates a substrate for AF. Oxidant radicals may promote increase of atrial oxidative damage, electrical and structural remodeling, and atrial inflammation. AF and other cardiovascular morbidities activate angiotensin (Ang-II)-dependent and independent cascades. A key component of the renin–angiotensin-aldosterone system (RAAS) is the mineralocorticoid aldosterone. Recent studies provide evidence of myocardial aldosterone synthesis. Aldosterone promotes cardiac oxidative stress, inflammation and structural/electrical remodeling via multiple mechanisms. In HF patients, aldosterone production is enhanced. In patients and in experimental HF and AF models, aldosterone receptor antagonists have favorable influences on cardiac remodeling and oxidative stress. Therapeutic approaches that seek to reduce AF burden by modulating the aldosterone system are likely beneficial but underutilized. PMID:23993726

Excessive Exercise in Endurance Athletes: Is Atrial Fibrillation a Possible Consequence?

PubMed

Goodman, Jack M; Banks, Laura; Connelly, Kim A; Yan, Andrew; Backx, Peter H; Dorian, Paul

2018-05-29

Moderate physical activity levels are associated with increased longevity and lower risk of atrial fibrillation (AF). However, the relative risk of lone AF is 3-5 fold higher in intensive endurance-trained athletes compared to healthy adults. There is growing concern that 'excessive' endurance exercise may promote cardiac remodeling leading to long-term adverse consequences. The pathogenesis of exercise-induced AF is thought to arise from an interplay of multiple acute and chronic factors, including atrial enlargement, pro-fibrotic tendency, high vagal tone, and genotypic profile, which collectively promote adverse atrial remodeling. Clinical management of athletes with AF, while challenging, can be achieved using various strategies that may allow continued, safe exercise. Based on the overall risk-benefit evidence, it is premature to suggest 'excessive' exercise is unsafe or should be curtailed. Evidence-based assessment and treatment guidelines are required to ensure optimal and safe exercise among the growing number of endurance athletes with AF.

Health Literacy and Atrial Fibrillation: Relevance and Future Directions for Patient-centred Care.

PubMed

Aronis, Konstantinos N; Edgar, Brittany; Lin, Wendy; Martins, Maria Auxiliadora Parreiras; Paasche-Orlow, Michael K; Magnani, Jared W

2017-01-01

Atrial fibrillation (AF) is a common cardiac arrhythmia with significant clinical outcomes, and is associated with high medical and social costs. AF is complicated for patients because of its specialised terminology, long-term adherence, symptom monitoring, referral to specialty care, array of potential interventions and potential for adversity. Health literacy is a frequently under-recognised, yet fundamental, component towards successful care in AF. Health literacy is defined as the capacity to obtain, process and understand health information, and has had markedly limited study in AF. However, health literacy could contribute to how patients interpret symptoms, navigate care, and participate in treatment evaluation and decision-making. This review aims to summarise the clinical importance and essential relevance of health literacy in AF. We focus here on central aspects of AF care that are most related to self-care, including understanding the symptoms of AF, shared decision-making, adherence and anticoagulation for stroke prevention. We discuss opportunities to enhance AF care based on findings from the literature on health literacy, and identify important gaps. Our overall objective is to articulate the importance and relevance of integrating health literacy in the care of individuals with AF.

Polish and European management strategies in patients with atrial fibrillation. Data from the EURObservational Research Programme-Atrial Fibrillation General Registry Pilot Phase (EORP-AF Pilot).

PubMed

Lenarczyk, Radosław; Mitręga, Katarzyna; Mazurek, Michał; Janion, Marianna; Opolski, Grzegorz; Drożdż, Jarosław; Streb, Witold; Fuglewicz, Artur; Sokal, Adam; Laroche, Cécile; Lip, Gregory Y H; Kalarus, Zbigniew

2016-01-01

Despite continued efforts of the European Society of Cardiology (ESC) to unify management of patients with atrial fibrillation (AF) across Europe, interregional differences in guideline adherence are likely. The aim of the study was to compare treatment strategies depending on baseline characteristics of AF patients between Poland and other members of the European Union (EU). We analyzed the baseline data and treatment strategies in participants of the ESC registry: the EURObservational Research Programme-Atrial Fibrillation General Registry Pilot Phase. A total of 3119 consecutive patients with AF diagnosed within the last year were included in 67 centers from 9 countries, including 419 patients enrolled in 15 Polish centers. A rhythm control strategy was more frequent in Poland than in other EU countries (20.8% vs 11.9%; P <0.0001). Catheter ablation for AF was also used more frequently in Polish cardiology wards (13.9% vs 8.3%; P = 0.0017), while amiodarone at discharge was used less frequently (12.0% vs 22.7%; P <0.0001). In-hospital use of vitamin K antagonists (VKAs) and non-VKA anticoagulants was less frequent in Polish patients with a CHA2DS2-VASc score of 2 or higher than in patients from other EU countries (61.1% vs 79.0%; P <0.0001), but overall anticoagulation rates at discharge were similar to those in other countries (83.3% vs 82.6%). A rhythm control-oriented strategy in patients with AF with the use of ablation in cardiology wards is more frequent in Poland than in other EU countries. Similar to other EU countries, compliance with the ESC guidelines regarding anticoagulation in AF patients is suboptimal in Poland. Undertreatment was observed in a significant proportion of patients at high risk of stroke, while a large group of low-risk patients are overtreated. Differences between the types of recruiting centers in Poland and other EU countries might have influenced the results.

Management of atrial fibrillation in seven European countries after the publication of the 2010 ESC Guidelines on atrial fibrillation: primary results of the PREvention oF thromboemolic events--European Registry in Atrial Fibrillation (PREFER in AF).

PubMed

Kirchhof, Paulus; Ammentorp, Bettina; Darius, Harald; De Caterina, Raffaele; Le Heuzey, Jean-Yves; Schilling, Richard John; Schmitt, Josef; Zamorano, Jose Luis

2014-01-01

We sought to describe the management of patients with atrial fibrillation (AF) in Europe after the release of the 2010 AF Guidelines of the European Society of Cardiology. The PREFER in AF registry enrolled consecutive patients with AF from January 2012 to January 2013 in 461 centres in seven European countries. Seven thousand two hundred and forty-three evaluable patients were enrolled, aged 71.5 ± 11 years, 60.1% male, CHA2DS2VASc score 3.4 ± 1.8 (mean ± standard deviation). Thirty per cent patients had paroxysmal, 24.0% had persistent, 7.2% had long-standing persistent, and 38.8% had permanent AF. Oral anticoagulation was used in the majority of patients: 4799 patients (66.3%) received a vitamin K antagonist (VKA) as mono-therapy, 720 patients a combination of VKA and antiplatelet agents (9.9%), 442 patients (6.1%) a new oral anticoagulant drugs (NOAC). Antiplatelet agents alone were given to 808 patients (11.2%), no antithrombotic therapy to 474 patients (6.5%). Of 7034 evaluable patients, 5530 (78.6%) patients were adequately rate controlled (mean heart rate 60-100 bpm). Half of the patients (50.7%) received rhythm control therapy by electrical cardioversion (18.1%), pharmacological cardioversion (19.5%), antiarrhythmic drugs (amiodarone 24.1%, flecainide or propafenone 13.5%, sotalol 5.5%, dronedarone 4.0%), and catheter ablation (5.0%). The management of AF patients in 2012 has adapted to recent evidence and guideline recommendations. Oral anticoagulant therapy with VKA (majority) or NOACs is given to over 80% of eligible patients, including those at risk for bleeding. Rate is often adequately controlled, and rhythm control therapy is widely used.

Second-harmonic generation imaging of collagen fibers in myocardium for atrial fibrillation diagnosis

NASA Astrophysics Data System (ADS)

Tsai, Ming-Rung; Chiu, Yu-Wei; Lo, Men Tzung; Sun, Chi-Kuang

2010-03-01

Atrial fibrillation (AF) is the most common irregular heart rhythm and the mortality rate for patients with AF is approximately twice the mortality rate for patients with normal sinus rhythm (NSR). Some research has indicated that myocardial fibrosis plays an important role in predisposing patients to AF. Therefore, realizing the relationship between myocardial collagen fibrosis and AF is significant. Second-harmonic generation (SHG) is an optically nonlinear coherent process to image the collagen network. We perform SHG microscopic imaging of the collagen fibers in the human atrial myocardium. Utilizing the SHG images, we can identify the differences in morphology and the arrangement of collagen fibers between NSR and AF tissues. We also quantify the arrangement of the collagen fibers using Fourier transform images and calculating the values of angle entropy. We indicate that SHG imaging, a nondestructive and reproducible method to analyze the arrangement of collagen fibers, can provide explicit information about the relationship between myocardial fibrosis and AF.

High prevalence of iatrogenic hyperthyroidism in elderly patients with atrial fibrillation in an anticoagulation clinic.

PubMed

Krishnan, Sandeep Kumar; Dohrmann, Mary L; Brietzke, Stephen A; Fleming, David A; Flaker, Greg C

2011-01-01

In elderly patients with established atrial fibrillation (AF) who are receiving thyroid replacement, regular testing for thyroid function is often not performed, placing the patient at risk for iatrogenic hyperthyroidism. Of 215 patients followed in an anticoagulation clinic, 41 were receiving thyroid replacement and 15 of these were found to have hyperthyroidism. Eight had documented AF coincident with abnormal thyroid function. In addition, only 22 patients on thyroid replacement had an annual TSH. In conclusion, iatrogenic hyperthyroidism may frequently be missed in AF patients because of inadequate monitoring of serum TSH. Thyroid replacement is common in elderly patients with AF followed in an anticoagulation clinic. Laboratory evidence of hyperthyroidism occurred in 37%, usually in patients with higher doses of thyroid replacement, and often associated with AF. The frequency of iatrogenic hyperthyroidism may be underestimated in patients with AF since many patients who receive thyroid replacement therapy are not monitored regularly with serum TSH.

Atrial fibrillation in the elderly: the potential contribution of reactive oxygen species

PubMed Central

Schillinger, Kurt J.; Patel, Vickas V.

2012-01-01

Atrial fibrillation (AF) is the most commonly encountered cardiac arrhythmia, and is a significant source of healthcare expenditures throughout the world. It is an arrhythmia with a very clearly defined predisposition for individuals of advanced age, and this fact has led to intense study of the mechanistic links between aging and AF. By promoting oxidative damage to multiple subcellular and cellular structures, reactive oxygen species (ROS) have been shown to induce the intra- and extra-cellular changes necessary to promote the pathogenesis of AF. In addition, the generation and accumulation of ROS have been intimately linked to the cellular processes which underlie aging. This review begins with an overview of AF pathophysiology, and introduces the critical structures which, when damaged, predispose an otherwise healthy atrium to AF. The available evidence that ROS can lead to damage of these critical structures is then reviewed. Finally, the evidence linking the process of aging to the pathogenesis of AF is discussed. PMID:23341843

Red Wine, Resveratrol and Atrial Fibrillation.

PubMed

Stephan, Laura Siga; Almeida, Eduardo Dytz; Markoski, Melissa Medeiros; Garavaglia, Juliano; Marcadenti, Aline

2017-10-30

Atrial fibrillation (AF) is a common cardiac arrhythmia that is associated with increased risk for cardiovascular disease and overall mortality. Excessive alcohol intake is a well-known risk factor for AF, but this correlation is less clear with light and moderate drinking. Besides, low doses of red wine may acutely prolong repolarization and slow cardiac conduction. Resveratrol, a bioactive polyphenol found in grapes and red wine, has been linked to antiarrhythmic properties and may act as an inhibitor of both intracellular calcium release and pathological signaling cascades in AF, eliminating calcium overload and preserving the cardiomyocyte contractile function. However, there are still no clinical trials at all that prove that resveratrol supplementation leads to improved outcomes. Besides, no observational study supports a beneficial effect of light or moderate alcohol intake and a lower risk of AF. The purpose of this review is to briefly describe possible beneficial effects of red wine and resveratrol in AF, and also present studies conducted in humans regarding chronic red wine consumption, resveratrol, and AF.

Red Wine, Resveratrol and Atrial Fibrillation

PubMed Central

Garavaglia, Juliano; Marcadenti, Aline

2017-01-01

Atrial fibrillation (AF) is a common cardiac arrhythmia that is associated with increased risk for cardiovascular disease and overall mortality. Excessive alcohol intake is a well-known risk factor for AF, but this correlation is less clear with light and moderate drinking. Besides, low doses of red wine may acutely prolong repolarization and slow cardiac conduction. Resveratrol, a bioactive polyphenol found in grapes and red wine, has been linked to antiarrhythmic properties and may act as an inhibitor of both intracellular calcium release and pathological signaling cascades in AF, eliminating calcium overload and preserving the cardiomyocyte contractile function. However, there are still no clinical trials at all that prove that resveratrol supplementation leads to improved outcomes. Besides, no observational study supports a beneficial effect of light or moderate alcohol intake and a lower risk of AF. The purpose of this review is to briefly describe possible beneficial effects of red wine and resveratrol in AF, and also present studies conducted in humans regarding chronic red wine consumption, resveratrol, and AF. PMID:29084143

The association between atrial fibrillation and cognitive function in patients with heart failure.

PubMed

Yang, Huifeng; Niu, Weihua; Zang, Xiaoying; Lin, Mei; Zhao, Yue

2017-02-01

Atrial fibrillation (AF) is associated with cognitive impairment in heart failure (HF). The purpose of this study was to examine whether AF independently predicted cognitive function in HF patients after controlling for more demographic, medical and psychological characteristics, and whether the timing of AF onset in relation to HF diagnosis independently contributed to cognitive function in HF patients with AF. A total of 188 hospitalized HF patients (62.8% male, age 66.3±10.6 years) completed cognitive function assessment with the Montreal Cognitive Assessment (MoCA). A history of AF, along with other medical characteristics, was ascertained through a review of participants' medical charts. The timing of AF onset in relation to HF diagnosis was categorized into AF occurring prior to HF diagnosis (i.e. prior AF) and AF developing after HF diagnosis (i.e. incident AF). Altogether 72 participants had a positive diagnostic history of AF. Specifically, 41 had prior AF, and 31 developed AF subsequently. In HF patients, AF was associated with poorer performance on cognitive function after controlling for more confounders (β=-0.112, ΔR 2 =0.010, p=0.046). Among HF patients with AF, incident AF independently predicted poorer cognitive function (β=-0.238, ΔR 2 =0.027, p=0.047). AF independently contributes to cognitive function in HF patients after adjusting for more confounding variables. The timing of AF onset in relation to HF diagnosis independently predicts cognitive function in HF patients with AF. Prospective studies are needed to elucidate possible mechanisms for the association between AF and cognitive function in HF populations.

Pro-arrhythmogenic effects of atrial fibrillation-induced electrical remodelling: insights from the three-dimensional virtual human atria

PubMed Central

Colman, Michael A; Aslanidi, Oleg V; Kharche, Sanjay; Boyett, Mark R; Garratt, Clifford; Hancox, Jules C; Zhang, Henggui

2013-01-01

Chronic atrial fibrillation (AF) is associated with structural and electrical remodelling in the atria, which are associated with a high recurrence of AF. Through biophysically detailed computer modelling, this study investigated mechanisms by which AF-induced electrical remodelling promotes and perpetuates AF. A family of Courtemanche–Ramirez–Nattel variant models of human atrial cell action potentials (APs), taking into account of intrinsic atrial electrophysiological properties, was modified to incorporate various experimental data sets on AF-induced changes of major ionic channel currents (ICaL, IKur, Ito, IK1, IKs, INaCa) and on intracellular Ca2+ handling. The single cell models for control and AF-remodelled conditions were incorporated into multicellular three-dimensional (3D) atrial tissue models. Effects of the AF-induced electrical remodelling were quantified as the changes of AP profile, AP duration (APD) and its dispersion across the atria, and the vulnerability of atrial tissue to the initiation of re-entry. The dynamic behaviour of re-entrant excitation waves in the 3D models was characterised. In our simulations, AF-induced electrical remodelling abbreviated atrial APD non-uniformly across the atria; this resulted in relatively short APDs co-existing with marked regional differences in the APD at junctions of the crista terminalis/pectinate muscle, pulmonary veins/left atrium. As a result, the measured tissue vulnerability to re-entry initiation at these tissue junctions was increased. The AF-induced electrical remodelling also stabilized and accelerated re-entrant excitation waves, leading to rapid and sustained re-entry. Under the AF-remodelled condition, re-entrant scroll waves in the 3D model degenerated into persistent and erratic wavelets, leading to fibrillation. In conclusion, realistic 3D atrial tissue models indicate that AF-induced electrical remodelling produces regionally heterogeneous and shortened APD; these respectively facilitate initiation and maintenance of re-entrant excitation waves. PMID:23732649

Pro-arrhythmogenic effects of atrial fibrillation-induced electrical remodelling: insights from the three-dimensional virtual human atria.

PubMed

Colman, Michael A; Aslanidi, Oleg V; Kharche, Sanjay; Boyett, Mark R; Garratt, Clifford; Hancox, Jules C; Zhang, Henggui

2013-09-01

Chronic atrial fibrillation (AF) is associated with structural and electrical remodelling in the atria, which are associated with a high recurrence of AF. Through biophysically detailed computer modelling, this study investigated mechanisms by which AF-induced electrical remodelling promotes and perpetuates AF. A family of Courtemanche-Ramirez-Nattel variant models of human atrial cell action potentials (APs), taking into account of intrinsic atrial electrophysiological properties, was modified to incorporate various experimental data sets on AF-induced changes of major ionic channel currents (ICaL, IKur, Ito, IK1, IKs, INaCa) and on intracellular Ca(2+) handling. The single cell models for control and AF-remodelled conditions were incorporated into multicellular three-dimensional (3D) atrial tissue models. Effects of the AF-induced electrical remodelling were quantified as the changes of AP profile, AP duration (APD) and its dispersion across the atria, and the vulnerability of atrial tissue to the initiation of re-entry. The dynamic behaviour of re-entrant excitation waves in the 3D models was characterised. In our simulations, AF-induced electrical remodelling abbreviated atrial APD non-uniformly across the atria; this resulted in relatively short APDs co-existing with marked regional differences in the APD at junctions of the crista terminalis/pectinate muscle, pulmonary veins/left atrium. As a result, the measured tissue vulnerability to re-entry initiation at these tissue junctions was increased. The AF-induced electrical remodelling also stabilized and accelerated re-entrant excitation waves, leading to rapid and sustained re-entry. Under the AF-remodelled condition, re-entrant scroll waves in the 3D model degenerated into persistent and erratic wavelets, leading to fibrillation. In conclusion, realistic 3D atrial tissue models indicate that AF-induced electrical remodelling produces regionally heterogeneous and shortened APD; these respectively facilitate initiation and maintenance of re-entrant excitation waves.

Intersection of Cardiovascular Disease and Kidney Disease: Atrial Fibrillation

PubMed Central

Bansal, Nisha; Hsu, Chi-yuan; Go, Alan S.

2014-01-01

Purpose of review Atrial fibrillation (AF) is the most common sustained arrhythmia in the patients with kidney disease. The purpose of this review is to describe the burden of AF in patients with chronic kidney disease (CKD) and end-stage renal disease (ESRD), postulate possible mechanisms to explain this burden of disease, understand the clinical consequences of AF and review the treatment options for AF specific to patients with kidney disease. Recent findings Recent literature has revealed that the clinical multi-organ impact of AF in patients with CKD and ESRD is substantial. Although novel oral anticoagulants to treat AF and prevent associated complications have been tested in large trials in the general population, there is a paucity of data on the efficacy and safety of these agents in patients with advanced CKD and ESRD. Summary AF is a significant comorbidity in patients with CKD and ESRD with important prognostic implications. More research is needed to understand the mechanisms that contribute to the disproportionate burden of this arrhythmia in patients with kidney disease and treatment options specific to this population of high-risk patients. PMID:24709949

Obstructive Sleep Apnea Treatment and Atrial Fibrillation: A Need for Definitive Evidence.

PubMed

Nalliah, Chrishan J; Sanders, Prashanthan; Kalman, Jonathan M

2016-08-01

Prevalence rates of atrial fibrillation (AF) and obstructive sleep apnea (OSA) are rising on a global scale. Epidemiological data have consistently demonstrated an independent association between the 2 conditions. Investigators pose that pathophysiologic features of OSA enable progression of the AF substrate; these features include abnormalities of gas exchange, autonomic remodeling, atrial stretch, and inflammation. Furthermore, many of the mechanistic perturbations that impact the AF substrate in OSA can be substantially attenuated by effective treatment with continuous positive airway pressure (CPAP). Clear associations of OSA treatment and improved AF control have been observed across multiple clinical contexts. However, the precision and generalizability of these findings are unclear in view of the data's observational nature. Although risk factor management has emerged as a critical component of AF treatment, effective control of many AF risk factors can be challenging in the longer term. In view of the efficacy and sustainability of CPAP therapy, OSA raises its profile as a prime candidate for intervention. However, translation of this strategy to the broader framework for AF management requires robust data from randomized controlled trials. © 2016 Wiley Periodicals, Inc.

Monotherapy of aspirin or warfarin for prevention of ischemic stroke in low-risk atrial fibrillation: A Easter Asian population-based study.

PubMed

Liu, Chieh-Yu; Chen, Hui-Chun

2018-05-02

This study aimed to investigate the effectiveness of monotherapy aspirin and warfarin for stroke prevention in low-risk atrial fibrillation (AF) by using a population-based cohort study in Taiwan. A newly diagnosed low-risk AF patient cohort were identified by using National Health Insurance Research Database (NHIRD) in Taiwan in 2008. The study cohort was observed with a follow-up of 2 years to examine the onset of ischemic stroke (IS) (to 2010). The longitudinal data were analyzed by using generalized estimation equations (GEE). A total of 8,065 newly-diagnosed low-risk AF patients were identified in 2008. 7.4% were prescribed with aspirin and 4.6% were prescribed with warfarin. The GEE results showed that low-risk AF patients with hypertension who received warfarin were associated with a statistically significant 58.4% reduction of IS risk (OR = 0.416, p = 0.024, 95% CI 0.194-0.891). Additionally, low-risk AF patients with hyperlipidemia who received warfarin were associated with a 69.3% reduction of IS risk (OR = 0.307, p = 0.044, 95% CI 0.097-0.969). Warfarin is suggested to be prescribed in preventing ischemic stroke for low-stroke-risk atrial fibrillation patients with hypertension and hyperlipidemia.

Outcomes after cardioversion and atrial fibrillation ablation in patients treated with rivaroxaban and warfarin in the ROCKET AF trial.

PubMed

Piccini, Jonathan P; Stevens, Susanna R; Lokhnygina, Yuliya; Patel, Manesh R; Halperin, Jonathan L; Singer, Daniel E; Hankey, Graeme J; Hacke, Werner; Becker, Richard C; Nessel, Christopher C; Mahaffey, Kenneth W; Fox, Keith A A; Califf, Robert M; Breithardt, Günter

2013-05-14

This study sought to investigate the outcomes following cardioversion or catheter ablation in patients with atrial fibrillation (AF) treated with warfarin or rivaroxaban. There are limited data on outcomes following cardioversion or catheter ablation in AF patients treated with factor Xa inhibitors. We compared the incidence of electrical cardioversion (ECV), pharmacologic cardioversion (PCV), or AF ablation and subsequent outcomes in patients in a post hoc analysis of the ROCKET AF (Efficacy and Safety Study of Rivaroxaban With Warfarin for the Prevention of Stroke and Non-Central Nervous System Systemic Embolism in Patients With Non-Valvular Atrial Fibrillation) trial. Over a median follow-up of 2.1 years, 143 patients underwent ECV, 142 underwent PCV, and 79 underwent catheter ablation. The overall incidence of ECV, PCV, or AF ablation was 1.45 per 100 patient-years (n = 321; 1.44 [n = 161] in the warfarin arm, 1.46 [n = 160] in the rivaroxaban arm). The crude rates of stroke and death increased in the first 30 days after cardioversion or ablation. After adjustment for baseline differences, the long-term incidence of stroke or systemic embolism (hazard ratio [HR]: 1.38; 95% confidence interval [CI]: 0.61 to 3.11), cardiovascular death (HR: 1.57; 95% CI: 0.69 to 3.55), and death from all causes (HR: 1.75; 95% CI: 0.90 to 3.42) were not different before and after cardioversion or AF ablation. Hospitalization increased after cardioversion or AF ablation (HR: 2.01; 95% CI: 1.51 to 2.68), but there was no evidence of a differential effect by randomized treatment (p value for interaction = 0.58). The incidence of stroke or systemic embolism (1.88% vs. 1.86%) and death (1.88% vs. 3.73%) were similar in the rivaroxaban-treated and warfarin-treated groups. Despite an increase in hospitalization, there were no differences in long-term stroke rates or survival following cardioversion or AF ablation. Outcomes were similar in patients treated with rivaroxaban or warfarin. (An Efficacy and Safety Study of Rivaroxaban With Warfarin for the Prevention of Stroke and Non-Central Nervous System Systemic Embolism in Patients With Non-Valvular Atrial Fibrillation [ROCKET AF]; NCT00403767). Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

High beat-to-beat blood pressure variability in atrial fibrillation compared to sinus rhythm.

PubMed

Olbers, Joakim; Gille, Adam; Ljungman, Petter; Rosenqvist, Mårten; Östergren, Jan; Witt, Nils

2018-02-07

Atrial fibrillation (AF) is associated with an increased risk for cardiovascular morbidity and mortality, not entirely explained by thromboembolism. The underlying mechanisms for this association are largely unknown. Similarly, high blood pressure (BP) increases the risk for cardiovascular events. Despite this the interplay between AF and BP is insufficiently studied. The purpose of this study was to examine and quantify the beat-to-beat blood pressure variability in patients with AF in comparison to a control group of patients with sinus rhythm. We studied 33 patients - 21 in atrial fibrillation and 12 in sinus rhythm - undergoing routine coronary angiography. Invasive blood pressure was recorded at three locations: radial artery, brachial artery and ascending aorta. Blood pressure variability, defined as average beat-to-beat blood pressure difference, was calculated for systolic and diastolic blood pressure at each site. We observed a significant difference (p < .001) in systolic and diastolic blood pressure variability between the atrial fibrillation and sinus rhythm groups at all locations. Systolic blood pressure variability roughly doubled in the atrial fibrillation group compared to the sinus rhythm group (4.9 and 2.4 mmHg respectively). Diastolic beat-to-beat blood pressure variability was approximately 6 times as high in the atrial fibrillation group compared to the sinus rhythm group (7.5 and 1.2 mmHg respectively). No significant difference in blood pressure variability was seen between measurement locations. Beat-to-beat blood pressure variability in patients with atrial fibrillation was substantially higher than in patients with sinus rhythm. Hemodynamic effects of this beat-to-beat variation in blood pressure may negatively affect vascular structure and function, which may contribute to the increased cardiovascular morbidity and mortality seen in patients with atrial fibrillation.

Incorporating Stroke and Bleeding Risk Stratification Tools into Atrial Fibrillation Management Making Sense of the Alphabet Soup.

PubMed

Deering, Thomas F

2017-01-01

Atrial fibrillation (AF) is a common arrhythmia managed by many physicians in a variety of clinical settings. One of the most important clinical decisions related to effective AF management centers upon the need to perform accurate thromboembolic risk stratification followed by effective management decisions that align with established guidelines. This manuscript will review the present state of the art and provide guidance to physicians to enhance patient outcomes.

Relationship of Preexisting Cardiovascular Comorbidities to Newly Diagnosed Atrial Fibrillation After Ischemic Stroke.

PubMed

Bisson, Arnaud; Clementy, Nicolas; Bodin, Alexandre; Angoulvant, Denis; Babuty, Dominique; Lip, Gregory Y H; Fauchier, Laurent

2017-10-01

There remains uncertainty as whether newly diagnosed atrial fibrillation (AF) after ischemic stroke reflects underlying heart disease and represents an increased risk of cardioembolic stroke, or whether it is triggered by neurogenic mechanisms. We aimed to determine whether cardiovascular comorbidities in patients with new AF after ischemic stroke differ from patients with previous known AF or without AF. This French longitudinal cohort study was based on the database covering hospital care from 2009 to 2012 for the entire population. Of 336 291 patients with ischemic stroke, 240 459 (71.5%) had no AF and 95 832 (28.5%) had previously known AF at baseline. Patients without previous AF had a mean CHA 2 DS 2 -VASc score of 4.98±1.63 SD. During a mean follow-up of 7.9±11.5 months, 14 095 (5.9%) of these patients had incident AF, representing an annual incidence of AF after ischemic stroke of 8.9 per 100 person-years (95% confidence interval, 8.8-9.0). New AF patients had higher CHA 2 DS 2 -VASc score, more likely comorbidities, and more frequent history of previous transient ischemic attack than patients with previous known AF or without AF. Preexisting cardiovascular comorbidities underlie AF newly diagnosed after stroke. Consequently, these high-risk patients should be closely monitored for incident AF to facilitate an earlier diagnosis of AF and avoid stroke with appropriate thromboprophylaxis. © 2017 American Heart Association, Inc.

A new predictor of atrial fibrillation after coronary artery bypass graft surgery: HATCH score.

PubMed

Selvi, Mithat; Gungor, Hasan; Zencir, Cemil; Gulasti, Sevil; Eryilmaz, Ufuk; Akgullu, Cagdas; Durmaz, Selim

2018-03-01

The aim of this study was to investigate the association between HATCH score and atrial fibrillation (AF) after coronary artery bypass graft (CABG) surgery. 369 patients (103 patients with AF and 266 patients without AF) undergoing isolated CABG surgery were analyzed. Complete medical records were retrospectively collected to investigate HATCH score. The median age of patients with AF was significantly higher than the median age of non-AF group (60.8±10.0 years vs 67.8±9.5 years, P<0.001). HATCH score was significantly higher in patients who developed AF after CABG surgery than the non-AF group (P=0.017). Multivariate logistic regression analysis showed that HATCH score (OR 1.334; 95% CI 1.022 to 1.741, P=0.034) was an independent predictor of AF after CABG surgery. Receiver operating characteristic curve analysis showed that the cut-off point of HATCH score related to predict AF was >1 (two or more), with a sensitivity of 42% and specificity of 70%. Patients with elevated preoperative HATCH score may have higher risk for AF after CABG surgery. © American Federation for Medical Research (unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

The future of anticoagulation management in atrial fibrillation in Europe: An assessment of today's challenges with recommendations for the future.

PubMed

Lichten, Catherine A; Castle-Clarke, Sophie; Manville, Catriona; Horvath, Veronika; Robin, Enora; Krapels, Joachim; Parks, Sarah; Sim, Megan; van Zijverden, Olga; Chataway, Joanna

2015-11-30

Atrial fibrillation (AF) is the most common type of cardiac arrhythmia, affecting approximately 1-2 per cent of the population worldwide. Those who suffer from AF have a five times higher risk of stroke. AF prevalence increases with age and it affects roughly 18 per cent of the population over 85. Consequently, as populations age, AF is becoming an increasingly significant public health issue. Over recent years there have been developments in treatment and management options, both for treating the arrhythmia directly, and assessing and reducing the risk of AF-related stroke, but there is a need to ensure that available knowledge is applied optimally to benefit patients so that opportunities to prevent AF-related stroke are not missed. The aims of this project were to assess the current landscape and explore the direction of future developments in AF management in Europe, with a focus on the use of anticoagulants in the prevention of AF-related stroke. Through rapid evidence assessment, key informant interviews, PESTLE analysis and the development and exploration of future scenarios, we have developed sets of shorter- and longer-term recommendations for improving AF-related patient outcomes. The short-term recommendations are: i) improve AF awareness among the public and policymakers; ii) support education about AF management for healthcare professionals and patients; and iii) maintain engagement in AF-related research across the health services.

An illness-specific version of the Revised Illness Perception Questionnaire in patients with atrial fibrillation (AF IPQ-R): Unpacking beliefs about treatment control, personal control and symptom triggers.

PubMed

Taylor, Elaina C; O'Neill, Mark; Hughes, Lyndsay D; Moss-Morris, Rona

2018-04-01

This study modified the Revised Illness Perception Questionnaire (IPQ-R) in patients with persistent atrial fibrillation (AF). Qualitative interviews and think-aloud techniques informed modification of the IPQ-R to be specific to AF patients. Confirmatory Factor Analysis (CFA) (n = 198) examined the validity of the modified IPQ-R (AF-IPQ-R). Exploratory factor analysis (EFA) examined the new AF-triggers scale. Construct validity examined associations between the AF-IPQ-R, quality of life (QoL) and beliefs about medicines. Test-retest and internal reliability were examined. Interviews indicated that patients viewed triggers of AF rather than initial causes of illness as more applicable. Patients believed specific behaviours such as rest could control AF. Treatment control beliefs related to pharmacological and procedural treatments. These data were used to modify the IPQ-R subscales and to develop a triggers of AF scale. CFA indicated good model fit. EFA of the triggers scale indicated three factors: emotional; health behaviours; and over-exertion triggers. Expected correlations were found between the AF-IPQ-R, QoL and treatment beliefs, evidencing good construct validity. The AF-IPQ-R showed sound psychometric properties. It provides more detailed specification than the IPQ-R of beliefs that may help to understand poor QoL in AF patients, and guidance for future interventions in this area.

Novel pharmacological targets for the rhythm control management of atrial fibrillation.

PubMed

Burashnikov, Alexander; Antzelevitch, Charles

2011-12-01

Atrial fibrillation (AF) is a growing clinical problem associated with increased morbidity and mortality. Development of safe and effective pharmacological treatments for AF is one of the greatest unmet medical needs facing our society. In spite of significant progress in non-pharmacological AF treatments (largely due to the use of catheter ablation techniques), anti-arrhythmic agents (AADs) remain first line therapy for rhythm control management of AF for most AF patients. When considering efficacy, safety and tolerability, currently available AADs for rhythm control of AF are less than optimal. Ion channel inhibition remains the principal strategy for termination of AF and prevention of its recurrence. Practical clinical experience indicates that multi-ion channel blockers are generally more optimal for rhythm control of AF compared to ion channel-selective blockers. Recent studies suggest that atrial-selective sodium channel block can lead to safe and effective suppression of AF and that concurrent inhibition of potassium ion channels may potentiate this effect. An important limitation of the ion channel block approach for AF treatment is that non-electrical factors (largely structural remodeling) may importantly determine the generation of AF, so that "upstream therapy", aimed at preventing or reversing structural remodeling, may be required for effective rhythm control management. This review focuses on novel pharmacological targets for the rhythm control management of AF. Copyright © 2011 Elsevier Inc. All rights reserved.

Atrial Fibrillation and Stroke

MedlinePlus

... either alone or with another antiplatelet agency like clopidogrel. Other treatments for AF include medications such as ... either alone or with another antiplatelet agency like clopidogrel. Other treatments for AF include medications such as ...

Risk of atrial fibrillation among bisphosphonate users: a multicenter, population-based, Italian study.

PubMed

Herrera, L; Leal, I; Lapi, F; Schuemie, M; Arcoraci, V; Cipriani, F; Sessa, E; Vaccheri, A; Piccinni, C; Staniscia, T; Vestri, A; Di Bari, M; Corrao, G; Zambon, A; Gregori, D; Carle, F; Sturkenboom, M; Mazzaglia, G; Trifiro, G

2015-05-01

Bisphosphonate treatment is used to prevent bone fractures. A controversial association of bisphosphonate use and risk of atrial fibrillation has been reported. In our study, current alendronate users were associated with a higher risk of atrial fibrillation as compared with those who had stopped bisphosphonate (BP) therapy for more than 1 year. Bisphosphonates are widely used to prevent bone fractures. Controversial findings regarding the association between bisphosphonate use and the risk of atrial fibrillation (AF) have been reported. The aim of this study was to evaluate the risk of AF in association with BP exposure. We performed a nested case-control study using the databases of drug-dispensing and hospital discharge diagnoses from five Italian regions. The data cover a period ranging from July 1, 2003 to December 31, 2006. The study population comprised new users of bisphosphonates aged 55 years and older. Patients were followed from the first BP prescription until an occurrence of an AF diagnosis (index date, i.e., ID), cancer, death, or the end of the study period, whichever came first. For the risk estimation, any AF case was matched by age and sex to up to 10 controls from the same source population. A conditional logistic regression was performed to obtain the odds ratio with 95% confidence intervals (CI). The BP exposure was classified into current (<90 days prior to ID), recent (91-180), past (181-364), and distant past (≥365) use, with the latter category being used as a reference point. A subgroup analysis by individual BP was then carried out. In comparison with distant past users of BP, current users of BP showed an almost twofold increased risk of AF: odds ratio (OR) = 1.78 and 95% CI = 1.46-2.16. Specifically, alendronate users were mostly associated with AF as compared with distant past use of BP (OR, 1.97; 95% CI, 1.59-2.43). In our nested case-control study, current users of BP are associated with a higher risk of atrial fibrillation as compared with those who had stopped BP treatment for more than 1 year.

The Effect of Atrial Fibrillation Ablation Techniques on P Wave Duration and P Wave Dispersion.

PubMed

Furniss, Guy O; Panagopoulos, Dimitrios; Kanoun, Sadeek; Davies, Edward J; Tomlinson, David R; Haywood, Guy A

2018-02-14

A reduction in surface electrocardiogram (ECG) P wave duration and dispersion is associated with improved outcomes in atrial fibrillation ablation. We investigated the effects of different ablation strategies on P wave duration and dispersion, hypothesising that extensive left atrial (LA) ablation with left atrial posterior wall isolation would give a greater reduction in P wave duration than more limited ablation techniques. A retrospective analysis of ECGs from patients who have undergone atrial fibrillation (AF) ablation was performed and pre-procedural sinus rhythm ECGs were compared with the post procedure ECGs. Maximal P wave duration was measured in leads I or II, minimum P wave duration in any lead and values were calculated for P wave duration and dispersion. Left atrial dimensions and medications at the time of ECG were documented. Ablation strategies compared were; pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (PAF) and the persistent AF (PsAF) ablation strategies of pulmonary vein isolation plus additional linear lesions (Lines), left atrial posterior wall isolation via catheter (PWI) and left atrial posterior wall isolation via staged surgical and catheter ablation (Hybrid). Sixty-nine patients' ECGs were analysed: 19 PVI, 21 Lines, 14 PWI, 15 Hybrid. Little correlation was seen between pre-procedure left atrial size and P wave duration (r=0.24) but LA size and P wave duration was larger in PsAF patients. A significant difference was seen in P wave reduction driven by Hybrid AF ablation (p<0.005) and Lines (<0.02). There was no difference amongst P wave dispersion between groups but the largest reduction was seen in the Hybrid ablation group. P wave duration increased with duration of continuous atrial fibrillation. Hybrid AF ablation significantly reduced P wave duration and dispersion compared to other ablation strategies including posterior wall isolation via catheter despite this being the same lesion set. Copyright © 2018 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

Low-dose green tea intake reduces incidence of atrial fibrillation in a Chinese population.

PubMed

Liu, Dong-Chen; Yan, Jian-Jun; Wang, You-Nan; Wang, Ze-Mu; Xie, Zhi-Yong; Ma, Yao; Yang, Yang; Yang, Li; Wang, Lian-Sheng

2016-12-20

The aim of the present study was to assessthe association between green tea intake and incidence of atrial fibrillation (AF) in a Chinese population. A total of 801 (mean age: 62 years; 56% male) subjects were enrolled: 401 AF patients and 400 controls. All subjects completed a questionnaire and the associations between their green tea drinking habits and incidence of AF were assessed using the odds ratio (OR) and binary logistic regression. After multivariate adjustment, green tea intake presented as a protective factor against the incidence of AF (OR: 0.349, 95% CI: 0.253-0.483, P < 0.001). The green tea protection showed downward trend with increasing green tea intake (P for the trend= 0.001). Low frequency, low concentration, short-term tea consumption was classified as low-dose green tea intake. Green tea intake decreased the incidence of both paroxysmal AF (OR: 0.307, 95% CI: 0.216-0.436, P < 0.001) and persistent AF (OR: 0.355, 95% CI: 0.261-0.482, P < 0.001) and may be associated with a decreased incidence of AF. This study suggests that low-dose green tea intake strongly protects against AF.

Atrial fibrillation and gastroesophageal reflux disease: the cardiogastric interaction.

PubMed

Linz, Dominik; Hohl, Mathias; Vollmar, Johanna; Ukena, Christian; Mahfoud, Felix; Böhm, Michael

2017-01-01

Atrial fibrillation (AF) is the most common sustained arrhythmia and is associated with significant morbidity and mortality. Multiple conditions like hypertension, heart failure, diabetes, sleep apnoea, and obesity play a role for the initiation and perpetuation of AF. Recently, a potential association between gastroesophageal reflux disease (GERD) and AF development has been proposed due to the close anatomic vicinity of the oesophagus and the left atrium. As an understanding of the association between acid reflux disease and AF may be important in the global multimodal treatment strategy to further improve outcomes in a subset of patients with AF, we discuss potential atrial arrhythmogenic mechanisms in patients with GERD, such as gastric and subsequent systemic inflammation, impaired autonomic stimulation, mechanical irritation due to anatomical proximity of the left atrium and the oesophagus, as well as common comorbidities like obesity and sleep-disordered breathing. Data on GERD and oesophageal lesions after AF-ablation procedures will be reviewed. Treatment of GERD to avoid AF or to reduce AF burden might represent a future treatment perspective but needs to be scrutinized in prospective trials. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

Developing a New Computer-Aided Clinical Decision Support System for Prediction of Successful Postcardioversion Patients with Persistent Atrial Fibrillation.

PubMed

Sterling, Mark; Huang, David T; Ghoraani, Behnaz

2015-01-01

We propose a new algorithm to predict the outcome of direct-current electric (DCE) cardioversion for atrial fibrillation (AF) patients. AF is the most common cardiac arrhythmia and DCE cardioversion is a noninvasive treatment to end AF and return the patient to sinus rhythm (SR). Unfortunately, there is a high risk of AF recurrence in persistent AF patients; hence clinically it is important to predict the DCE outcome in order to avoid the procedure's side effects. This study develops a feature extraction and classification framework to predict AF recurrence patients from the underlying structure of atrial activity (AA). A multiresolution signal decomposition technique, based on matching pursuit (MP), was used to project the AA over a dictionary of wavelets. Seven novel features were derived from the decompositions and were employed in a quadratic discrimination analysis classification to predict the success of post-DCE cardioversion in 40 patients with persistent AF. The proposed algorithm achieved 100% sensitivity and 95% specificity, indicating that the proposed computational approach captures detailed structural information about the underlying AA and could provide reliable information for effective management of AF.

Transient cerebral hypoperfusion and hypertensive events during atrial fibrillation: a plausible mechanism for cognitive impairment

NASA Astrophysics Data System (ADS)

Anselmino, Matteo; Scarsoglio, Stefania; Saglietto, Andrea; Gaita, Fiorenzo; Ridolfi, Luca

2016-06-01

Atrial fibrillation (AF) is associated with an increased risk of dementia and cognitive decline, independent of strokes. Several mechanisms have been proposed to explain this association, but altered cerebral blood flow dynamics during AF has been poorly investigated: in particular, it is unknown how AF influences hemodynamic parameters of the distal cerebral circulation, at the arteriolar and capillary level. Two coupled lumped-parameter models (systemic and cerebrovascular circulations, respectively) were here used to simulate sinus rhythm (SR) and AF. For each simulation 5000 cardiac cycles were analyzed and cerebral hemodynamic parameters were calculated. With respect to SR, AF triggered a higher variability of the cerebral hemodynamic variables which increases proceeding towards the distal circulation, reaching the maximum extent at the arteriolar and capillary levels. This variability led to critical cerebral hemodynamic events of excessive pressure or reduced blood flow: 303 hypoperfusions occurred at the arteriolar level, while 387 hypertensive events occurred at the capillary level during AF. By contrast, neither hypoperfusions nor hypertensive events occurred during SR. Thus, the impact of AF per se on cerebral hemodynamics candidates as a relevant mechanism into the genesis of AF-related cognitive impairment/dementia.

Low-dose green tea intake reduces incidence of atrial fibrillation in a Chinese population

PubMed Central

Wang, Ze-Mu; Xie, Zhi-Yong; Ma, Yao; Yang, Yang; Yang, Li; Wang, Lian-Sheng

2016-01-01

The aim of the present study was to assessthe association between green tea intake and incidence of atrial fibrillation (AF) in a Chinese population. A total of 801 (mean age: 62 years; 56% male) subjects were enrolled: 401 AF patients and 400 controls. All subjects completed a questionnaire and the associations between their green tea drinking habits and incidence of AF were assessed using the odds ratio (OR) and binary logistic regression. After multivariate adjustment, green tea intake presented as a protective factor against the incidence of AF (OR: 0.349, 95% CI: 0.253-0.483, P < 0.001). The green tea protection showed downward trend with increasing green tea intake (P for the trend= 0.001). Low frequency, low concentration, short-term tea consumption was classified as low-dose green tea intake. Green tea intake decreased the incidence of both paroxysmal AF (OR: 0.307, 95% CI: 0.216-0.436, P < 0.001) and persistent AF (OR: 0.355, 95% CI: 0.261-0.482, P < 0.001) and may be associated with a decreased incidence of AF. This study suggests that low-dose green tea intake strongly protects against AF. PMID:27683043

The predictive role of E/e' on ischemic stroke and atrial fibrillation in Japanese patients without atrial fibrillation.

PubMed

Arai, Riku; Suzuki, Shinya; Semba, Hiroaki; Arita, Takuto; Yagi, Naoharu; Otsuka, Takayuki; Sagara, Koichi; Sasaki, Kenichi; Kano, Hiroto; Matsuno, Shunsuke; Kato, Yuko; Uejima, Tokuhisa; Oikawa, Yuji; Kunihara, Takashi; Yajima, Junji; Yamashita, Takeshi

2018-07-01

The predictive role of E/e' on ischemic stroke (IS) and atrial fibrillation (AF) in Japanese patients without AF are unclear. Shinken database includes all the new patients visiting the Cardiovascular Institute Hospital in Tokyo, Japan. E/e' has been routinely measured since 2007. Patients without AF for whom E/e' was measured at the initial visit between 2007 and 2014 (n=11 477, mean age 57.2 years old, men 59.5%) were divided into E/e' tertiles (<8.04, 8.04-11.00, >11.00). During the mean follow-up period of 1.8 years, 58 IS and 140 new appearances of AF were observed. High E/e' tertile was associated with more prevalence of atherothrombotic risks. The cumulative incidence of IS events and new appearance of AF at 6 years in low, middle, and high E/e' tertiles were 0.5%, 1.4%, and 3.0%/year (log-rank test, p<0.001), and 2.5%, 2.9%, and 4.2%/year (log-rank test, p=0.007), respectively. In multivariate analysis, high E/e' tertile was independently associated with IS (HR, 2.857, 95%CI 1.257-6.495, p=0.012). Although high E/e' tertile was independently associated with new appearance of AF when adjusted for coexistence of atherothrombotic risk factors (HR, 1.694, 95%CI, 1.097-2.616, p=0.017), the association was attenuated after adjustment for left atrial dimension. E/e' was significantly associated with incidence of IS and new appearance of AF in non-AF patients. Copyright © 2018 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

A novel, simple scale for assessing the symptom severity of atrial fibrillation at the bedside: the CCS-SAF scale.

PubMed

Dorian, Paul; Cvitkovic, Suzan S; Kerr, Charles R; Crystal, Eugene; Gillis, Anne M; Guerra, Peter G; Mitchell, L Brent; Roy, Denis; Skanes, Allan C; Wyse, D George

2006-04-01

The severity of symptoms caused by atrial fibrillation (AF) is extremely variable. Quantifying the effect of AF on patient well-being is important but there is no simple, commonly accepted measure of the effect of AF on quality of life (QoL). Current QoL measures are cumbersome and impractical for clinical use. To create a simple, concise and readily usable AF severity score to facilitate treatment decisions and physician communication. The Canadian Cardiovascular Society (CCS) Severity of Atrial Fibrillation (SAF) Scale is analogous to the CCS Angina Functional Class. The CCS-SAF score is determined using three steps: documentation of possible AF-related symptoms (palpitations, dyspnea, dizziness/syncope, chest pain, weakness/fatigue); determination of symptom-rhythm correlation; and assessment of the effect of these symptoms on patient daily function and QoL. CCS-SAF scores range from 0 (asymptomatic) to 4 (severe impact of symptoms on QoL and activities of daily living). Patients are also categorized by type of AF (paroxysmal versus persistent/permanent). The CCS-SAF Scale will be validated using accepted measures of patient-perceived severity of symptoms and impairment of QoL and will require 'field testing' to ensure its applicability and reproducibility in the clinical setting. This type of symptom severity scale, like the New York Heart Association Functional Class for heart failure symptoms and the CCS Functional Class for angina symptoms, trades precision and comprehensiveness for simplicity and ease of use at the bedside. A common language to quantify AF severity may help to improve patient care.

Patient-Reported Outcomes for Quality of Life Assessment in Atrial Fibrillation: A Systematic Review of Measurement Properties.

PubMed

Kotecha, Dipak; Ahmed, Amar; Calvert, Melanie; Lencioni, Mauro; Terwee, Caroline B; Lane, Deirdre A

2016-01-01

Atrial fibrillation is a large and growing burden across all types of healthcare. Both incidence and prevalence are expected to double in the next 20 years, with huge impact on hospital admissions, costs and patient quality of life. Patient wellbeing determines the management strategy for atrial fibrillation, including the use of rhythm control therapy and the clinical success of heart rate control. Hence, evaluation of quality of life is an emerging and important part of the assessment of patients with atrial fibrillation. Although a number of questionnaires to assess quality of life in atrial fibrillation are available, a comprehensive overview of their measurement properties is lacking. We performed a systematic review of the measurement properties of atrial fibrillation-specific health-related quality of life questionnaires. Methodological quality was assessed using the Consensus based Standards for selection of health Measurement Instruments (COSMIN) checklist, with measurement properties rated for quality against optimal criteria and levels of evidence. We screened 2,216 articles, of which eight articles describing five questionnaires were eligible for inclusion: Atrial Fibrillation 6 (AF6), Atrial Fibrillation Effect on QualiTy-of-Life (AFEQT), Atrial Fibrillation Quality of Life Questionnaire (AFQLQ), Atrial Fibrillation Quality of Life (AFQoL), and Quality of Life in Atrial Fibrillation (QLAF). Good reliability (internal consistency and test-retest reliability) was demonstrated for AF6, AFEQT, AFQLQ and AFQoL. Content, construct and criterion validity were positively rated only in AFEQT. Responsiveness was positively rated only in AFEQT, but with limited evidence. Overall, AFEQT showed strong positive evidence for 2 of 9 measurement properties, compared to one for AFQoL and none for the remaining questionnaires. Given the low ratings for many measurement properties, no single questionnaire can be recommended, although AFEQT performed strongest. Further studies to robustly assess reliability, validity and responsiveness of AF-specific quality of life questionnaires are required. This review consolidates the current evidence for quality of life assessment in patients with atrial fibrillation and identifies priority areas for future research.

Clinical Implications of Ablation of Drivers for Atrial Fibrillation: A Systematic Review and Meta-Analysis.

PubMed

Baykaner, Tina; Rogers, Albert J; Meckler, Gabriela L; Zaman, Junaid; Navara, Rachita; Rodrigo, Miguel; Alhusseini, Mahmood; Kowalewski, Christopher A B; Viswanathan, Mohan N; Narayan, Sanjiv M; Clopton, Paul; Wang, Paul J; Heidenreich, Paul A

2018-05-01

The outcomes from pulmonary vein isolation (PVI) for atrial fibrillation (AF) are suboptimal, but the benefits of additional lesion sets remain unproven. Recent studies propose ablation of AF drivers improves outcomes over PVI, yet with conflicting reports in the literature. We undertook a systematic literature review and meta-analysis to determine outcomes from ablation of AF drivers in addition to PVI or as a stand-alone procedure. Database search was done using the terms atrial fibrillation and ablation or catheter ablation and driver or rotor or focal impulse or FIRM (Focal Impulse and Rotor Modulation). We pooled data using random effects model and assessed heterogeneity with I 2 statistic. Seventeen studies met inclusion criteria, in a cohort size of 3294 patients. Adding AF driver ablation to PVI reported freedom from AF of 72.5% (confidence interval [CI], 62.1%-81.8%; P <0.01) and from all arrhythmias of 57.8% (CI, 47.5%-67.7%; P <0.01). AF driver ablation when added to PVI or as stand-alone procedure compared with controls produced an odds ratio of 3.1 (CI, 1.3-7.7; P =0.02) for freedom from AF and an odds ratio of 1.8 (CI, 1.2-2.7; P <0.01) for freedom from all arrhythmias in 4 controlled studies. AF termination rate was 40.5% (CI, 30.6%-50.9%) and predicted favorable outcome from ablation( P <0.05). In controlled studies, the addition of AF driver ablation to PVI supports the possible benefit of a combined approach of AF driver ablation and PVI in improving single-procedure freedom from all arrhythmias. However, most studies are uncontrolled and are limited by substantial heterogeneity in outcomes. Large multicenter randomized trials are needed to precisely define the benefits of adding driver ablation to PVI. © 2018 American Heart Association, Inc.

PubMed Central

RUSSO, VINCENZO; DI MEO, FEDERICA; PAPA, ANDREA ANTONIO; CIOPPA, NADIA DELLA; PROIETTI, RICCARDO; RUSSO, MARIA GIOVANNA; CALABRÒ, RAFFAELE; POLITANO, LUISA

2014-01-01

P-wave dispersion is a non invasive indicator of intra-atrial conduction heterogeneity producing substrate for reentry, which is a pathophysiological mechanism of atrial fibrillation. The relationship between P-wave dispersion (PD) and atrial fibrillation (AF) in Myotonic dystrophy type 1 (DM1) patients is still unclear. Atrial Preference Pacing (APP) is an efficient algorithm to prevent paroxysmal AF in patients implanted with dual-chamber pacemaker. Aim of our study was to evaluate the possible correlation between atrial preference pacing algorithm, P-wave dispersion and AF burden in DM1 patients with normal cardiac function underwent permanent dual-chamber pacemaker implantation. We enrolled 50 patients with DM1 (age 50.3 ± 7.3; 11 F) underwent dual-chamber pacemaker implantation for various degree of atrioventricula block. The study population was randomized following 1 months stabilization period to APP algorithm features programmed OFF or ON. Patients were assessed every 3 months for the first year, and every 6 months thereafter up to 3 years. At each follow-up visit, we counted: the number of premature atrial beats, the number and the mean duration of AF episodes, AF burden and the percentage of atrial and ventricular pacing. APP ON Group showed lower number of AF episodes (117 ± 25 vs. 143 ± 37; p = 0.03) and AF burden (3059 ± 275 vs. 9010 ± 630 min; p < 0.04) than APP OFF Group. Atrial premature beats count (44903 ± 30689 vs. 13720 ± 7717 beats; p = 0.005) and Pwave dispersion values (42,1 ± 11 ms vs. 29,1 ± 4,2 ms, p = 0,003) were decreased in APP ON Group. We found a significant positive correlation between PD and AF burden (R = 0,8, p = 0.007). Atrial preference pacing algorithm, decreasing the number of atrial premature beats and the P-wave dispersion, reduces the onset and perpetuator factors of AF episodes and decreases the AF burden in DM1 patients underwent dual chamber pacemaker implantation for various degree of atrioventricular blocks and documented atrial fibrillation. PMID:25873781

Prevalence and mechanism of rotor activation identified during atrial fibrillation by noncontact mapping: Lack of evidence for a role in the maintenance of atrial fibrillation.

PubMed

Yamabe, Hiroshige; Kanazawa, Hisanori; Ito, Miwa; Kaneko, Shozo; Ogawa, Hisao

2016-12-01

It remains unclear whether atrial fibrillation (AF) is maintained by the rotor. We evaluated the role of the rotor and examined its mechanism. Among 75 patients with AF (60 paroxysmal, 15 persistent AF) who underwent 3-dimensional noncontact left atrial mapping during AF, we examined the prevalence and location of rotor activation and elucidated its mechanism. Catheter ablation was performed in a stepwise fashion (linear roof lesion and complex fractionated atrial electrogram ablation after pulmonary vein [PV) isolation) until AF termination. Rotor activation was observed in 11 patients (14.7%; 10 paroxysmal and 1 persistent AF) (tachycardia cycle length 160.0 ± 19.8 ms). Rotors were observed transiently (duration 6128 ± 9094 ms) during AF at the roof (n = 5), septum (n = 3), and ostium of the left superior PV (n = 3). Five rotors circulated in clockwise and 6 in counterclockwise directions. The length of the block line at the center of the rotor was 15.2 ± 6.9 mm. The electrograms at the block line showed low-amplitude multiple deflections (n = 7) or double potentials (n = 4), and the amplitudes during rotor activation were significantly lower than those during sinus rhythm (0.27 ± 0.18 mV vs 1.22 ± 0.92 mV; P < .01). No conduction disturbances were found during sinus rhythm, suggesting that the central line of block was formed functionally. AF was terminated by PV isolation alone without additional lesions in patients with rotors. Functionally formed rotor activation was observed during AF in a limited number of patients. These rotor activations may not be related to AF maintenance, but rather may reflect a transient organization of random propagation. Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

The definition of success in atrial fibrillation ablation surgery.

PubMed

Hunter, Steven

2014-01-01

In spite of recent attempts to define and clarify the treatment endpoints in atrial fibrillation (AF) ablation surgery, the definition of success has remained blurred. It is of importance to address the burden of AF in the non-symptomatic population. Thromboembolic events invariably blight the outcomes, therefore freedom from stroke must be incorporated into any definition of success and guidelines. It is essential to meticulously study the long-term outcomes of an unsuccessful treatment as a supplement to the definition of success.

Factors Associated with the Incidence and Severity of New-Onset Atrial Fibrillation in Adult Critically Ill Patients

PubMed Central

Leichtweis, Gustavo Elias; Andriolo, Luiza; Delevatti, Yasmim A.; Jorge, Amaury C.; Fumagalli, Andreia C.; Santos, Luiz Claudio; Miura, Cecilia K.; Saito, Sergio K.

2017-01-01

Background Acute Atrial Fibrillation (AF) is common in critically ill patients, with significant morbidity and mortality; however, its incidence and severity in Intensive Care Units (ICUs) from low-income countries are poorly studied. Additionally, impact of vasoactive drugs on its incidence and severity is still not understood. This study aimed to assess epidemiology and risk factors for acute new-onset AF in critically ill adult patients and the role of vasoactive drugs. Method Cohort performed in seven general ICUs (including cardiac surgery) in three cities in Paraná State (southern Brazil) for 45 days. Patients were followed until hospital discharge. Results Among 430 patients evaluated, the incidence of acute new-onset AF was 11.2%. Patients with AF had higher ICU and hospital mortality. Vasoactive drugs use (norepinephrine and dobutamine) was correlated with higher incidence of AF and higher mortality in patients with AF; vasopressin (though used in few patients) had no effect on development of AF. Conclusions In general ICU patients, incidence of new-onset AF was 11.2% with a high impact on morbidity and mortality, particularly associated with the presence of Acute Renal Failure. The use of vasoactive drugs (norepinephrine and dobutamine) could lead to a higher incidence of new-onset AF-associated morbidity and mortality. PMID:28702263

Factors Associated with the Incidence and Severity of New-Onset Atrial Fibrillation in Adult Critically Ill Patients.

PubMed

Duarte, Péricles A D; Leichtweis, Gustavo Elias; Andriolo, Luiza; Delevatti, Yasmim A; Jorge, Amaury C; Fumagalli, Andreia C; Santos, Luiz Claudio; Miura, Cecilia K; Saito, Sergio K

2017-01-01

Acute Atrial Fibrillation (AF) is common in critically ill patients, with significant morbidity and mortality; however, its incidence and severity in Intensive Care Units (ICUs) from low-income countries are poorly studied. Additionally, impact of vasoactive drugs on its incidence and severity is still not understood. This study aimed to assess epidemiology and risk factors for acute new-onset AF in critically ill adult patients and the role of vasoactive drugs. Cohort performed in seven general ICUs (including cardiac surgery) in three cities in Paraná State (southern Brazil) for 45 days. Patients were followed until hospital discharge. Among 430 patients evaluated, the incidence of acute new-onset AF was 11.2%. Patients with AF had higher ICU and hospital mortality. Vasoactive drugs use (norepinephrine and dobutamine) was correlated with higher incidence of AF and higher mortality in patients with AF; vasopressin (though used in few patients) had no effect on development of AF. In general ICU patients, incidence of new-onset AF was 11.2% with a high impact on morbidity and mortality, particularly associated with the presence of Acute Renal Failure. The use of vasoactive drugs (norepinephrine and dobutamine) could lead to a higher incidence of new-onset AF-associated morbidity and mortality.

Hypertension and Atrial Fibrillation: An Intimate Association of Epidemiology, Pathophysiology, and Outcomes.

PubMed

Dzeshka, Mikhail S; Shahid, Farhan; Shantsila, Alena; Lip, Gregory Y H

2017-08-01

Atrial fibrillation (AF) is the most prevalent sustained arrhythmia found in clinical practice. AF rarely exists as a single entity but rather as part of a diverse clinical spectrum of cardiovascular diseases, related to structural and electrical remodeling within the left atrium, leading to AF onset, perpetuation, and progression. Due to the high overall prevalence within the AF population arterial hypertension plays a significant role in the pathogenesis of AF and its complications. Fibroblast proliferation, apoptosis of cardiomyocytes, gap junction remodeling, accumulation of collagen both in atrial and ventricular myocardium all accompany ageing-related structural remodeling with impact on electrical activity. The presence of hypertension also stimulates oxidative stress, systemic inflammation, rennin-angiotensin-aldosterone and sympathetic activation, which further drives the remodeling process in AF. Importantly, both hypertension and AF independently increase the risk of cardiovascular and cerebrovascular events, e.g., stroke and myocardial infarction. Given that both AF and hypertension often present with limited on patient wellbeing, treatment may be delayed resulting in development of complications as the first clinical manifestation of the disease. Antithrombotic prevention in AF combined with strict blood pressure control is of primary importance, since stroke risk and bleeding risk are both greater with underlying hypertension. © American Journal of Hypertension, Ltd 2017. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

[ESC guidelines on atrial fibrillation 2016 : Summary of the most relevant recommendations and modifications].

PubMed

Eckardt, L; Häusler, K G; Ravens, U; Borggrefe, M; Kirchhof, P

2016-12-01

The first European Society of Cardiology (ESC) guidelines on atrial fibrillation (AF) developed in collaboration with the European Association for Cardio-Thoracic Surgery (EACTS) were published in August 2016. These guidelines replace the revised guidelines from 2012 and contain some interesting new aspects. The topics range from the pathophysiology through diagnostics, therapy and stroke prevention up to special clinical situations, such as atrial fibrillation in cardiopathy, sport and pregnancy. Early screening, patient informed consent, individualized therapy and the modification of factors promoting atrial fibrillation are of particular importance. The guidelines recommend the establishment of AF heart teams, containing specialists from various disciplines. The guidelines also underline the importance of non-vitamin K‑dependent oral anticoagulants (NOAC) for stroke prevention compared to standard anticoagulants with vitamin K antagonists. For symptomatic and especially paroxysmal atrial fibrillation, the guidelines emphasize the importance of an antiarrhythmic treatment with catheter ablation and/or pharmaceutical antiarrhythmic therapy in addition to a frequency regulating therapy.

Recognizing an Irregular Heart Rhythm

MedlinePlus

... a workout, consider checking your rhythm as well. Atrial fibrillation, also referred to as AF, is a common ... upper chambers, or atria, of the heart. “While atrial fibrillation is not common among young people, it can ...

A brief history of 'lone' atrial fibrillation: from 'a peculiar pulse irregularity' to a modern public health concern.

PubMed

Potpara, Tatjana S; Lip, Gregory Y H

2015-01-01

Ever since the original description of a 'peculiar pulse irregularity', atrial fibrillation (AF) has been studied extensively and has come a long journey from the recognition of its cardiac origins, to the modern concept of AF as a serious public health challenge with profound social and economic implications. This arrhythmia affects around 2% of adult population, and the most common underlying heart diseases accompanying AF in the modern era are hypertension, heart failure and coronary artery disease, as well as valvular heart diseases and numerous other cardiac as well as non-cardiac disorders which have been shown to predispose to AF. On occasions, AF occurs in young otherwise apparently healthy individuals (so called 'lone AF'). For a long time, 'lone' AF has been believed to bear a favourable prognosis as compared to AF with underlying structural heart disease, but increasing evidence suggests that 'lone' AF patients represent a rather heterogeneous cohort, with highly variable individual risk profiles due to the presence of various subclinical cardiovascular risk factors or genetically determined subtle alterations at the cellular or molecular level. For these reasons, the existence of truly 'lone' AF has recently been questioned. In this review article, we present a brief history of the recognition of the public health burden of AF. We discuss some of the misconceptions and breakthroughs on modern knowledge on AF, including the rise (and fall) of the 'lone' AF concept.

Current status of the surgical treatment of atrial fibrillation.

PubMed

Geha, Alexander S; Abdelhady, Khaled

2008-03-01

Atrial fibrillation (AF) affects several million patients worldwide and is associated with a number of heart conditions, particularly coronary artery disease, rheumatic heart disease, hypertension, and congestive heart failure. The treatment of AF and its complications is quite costly. Atrial fibrillation usually results from multiple macro-re-entrant circuits in the left atrium. Very frequently, particularly in association with mitral valve disease, these circuits arise from the area of the junction of the pulmonary venous endothelium and the left atrial endocardium. Pharmacological therapy is at best 50% effective. Therapeutic options for AF include antiarrhythmic drugs, cardioversion, atrioventricular (A-V) node block, pacemaker insertion, and ablative surgery. In 1987, Cox developed an effective surgical procedure to achieve ablation. Current ablative procedures include the classic cut-and-sew Maze operation or a modification of it, namely through catheter ablation, namely, cryoablation, radiofrequency ablation (dry or irrigated), and other forms of ablation (e.g., laser, microwave). These procedures will be described, along with the indications, advantages and disadvantages of each. Special emphasis on the alternative means to cutting and sewing to achieve appropriate effective atrial scars will be stressed, and our experience with these approaches in 50 patients with AF and associated cardiac lesions and their outcomes is presented.

Impact of high-grade Atrioventricular block and cumulative frequent pacing on atrial arrhythmias.

PubMed

Wali, Eisha; Deshmukh, Amrish; Bukari, Abdallah; Broman, Michael; Aziz, Zaid; Beaser, Andrew; Upadhyay, Gaurav; Nayak, Hemal M; Tung, Roderick; Ozcan, Cevher

2018-06-21

The relationship between high-grade AV block (HGAVB) with cumulative frequent pacing and risk of atrial arrhythmias (AAs) has not been well characterized. We hypothesized HGAVB and pacing may have significant impact on incidence and prevalence of AAs by modulating atrial substrate. To determine impact of HGAVB and pacing on AAs including atrial fibrillation (AF), atrial flutter (AFL), and atrial tachycardia (AT). All consecutive patients who underwent dual chamber pacemaker implantation for HGAVB from 2005 to 2011 at the University of Chicago were included. AAs and percent of pacing were detected through device interrogation. Patients' data were collected from electronic medical records and clinic visits. A total of 166 patients (mean age 71±15 years; 54% female, 56% African-American) were studied. AF was documented in 27% of patients before pacemaker implantation. During a mean 5.8±2.2 years of follow-up, 47% had device-detected AF, 10% AFL and 26% AT. New-onset AF was documented in 40 of the 122 patients without prior AF (33%). Continuous (≥99%) right ventricular pacing was associated with significantly decreased AF prevalence (34% versus 59%, p = 0.005), and correlated with lower incidence (26% versus 41%, p = 0.22). Pacing suppressed AF in 14% of patients with baseline AF; those patients had lower atrial pacing (3.2% versus 45%, p < 0.0001). Left atrial dilation was the only independent predictor of AF with frequent pacing (p = 0.009). HGAVB is associated with high incidence and prevalence of AAs with and without pacing. Cumulative frequent (≥99%) ventricular pacing reduces risk of AF in patients with HGAVB. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Validation of a classification system to grade fractionation in atrial fibrillation and correlation with automated detection systems.

PubMed

Hunter, Ross J; Diab, Ihab; Thomas, Glyn; Duncan, Edward; Abrams, Dominic; Dhinoja, Mehul; Sporton, Simon; Earley, Mark J; Schilling, Richard J

2009-12-01

We tested application of a grading system describing complex fractionated electrograms (CFE) in atrial fibrillation (AF) and used it to validate automated CFE detection (AUTO). Ten seconds bipolar electrograms were classified by visual inspection (VI) during ablation of persistent AF and the result compared with offline manual measurement (MM) by a second blinded operator: Grade 1 uninterrupted fractionated activity (defined as segments > or =70 ms) for > or =70% of recording and uninterrupted > or =1 s; Grade 2 interrupted fractionated activity > or =70% of recording; Grade 3 intermittent fractionated activity 30-70%; Grade 4 discrete (<70 ms) complex electrogram (> or =5 direction changes); Grade 5 discrete simple electrograms (< or =4 direction changes); Grade 6 scar. Grade by VI and MM for 100 electrograms agreed in 89%. Five hundred electrograms were graded on Carto and NavX by VI to validate AUTO in (i) detection of CFE (grades 1-4 considered CFE), and (ii) assessing degree of fractionation by correlating grade and score by AUTO (data shown as sensitivity, specificity, r): NavX 'CFE mean' 92%, 91%, 0.56; Carto 'interval confidence level' using factory settings 89%, 62%, -0.72, and other published settings 80%, 74%, -0.65; Carto 'shortest confidence interval' 74%, 70%, 0.43; Carto 'average confidence interval' 86%, 66%, 0.53. Grading CFE by VI is accurate and correlates with AUTO.

Cardiac telocytes. From basic science to cardiac diseases. I. Atrial fibrillation.

PubMed

Hostiuc, Sorin; Negoi, Ionuț; Dogaroiu, Catalin; Drima, Eduard; Iancu, Cristian Bogdan

2018-04-12

Atrial fibrillation (AF) is nowadays considered to be one of the most important causes of heart failure, stroke, cognitive decline, vascular dementia, sudden death and overall cardiovascular morbidity. Recently were published a few articles suggesting a possible involvement of telocytes in the development of atrial fibrillation. The purpose of this article is to analyze the results obtained in the field systematically, and to see if there is enough data to support a possible involvement of telocytes in arrhythmogenesis. To this end, we performed a systematic review of the relevant scientific literature, indexed in PubMed, Web of Science, and Scopus. Our systematic review of the published data identified five articles containing original data, based on which the association between telocytes and atrial fibrillation was inferred in later studies. We analyzed the usefulness of the information contained in the original articles to support this association, showing a lack of definite proofs correlating telocytes with atrial fibrillation. Even if a few articles implied a potential association between AF and telocytes, the current data is not enough to support it. Moreover, even an association between the morphology, characteristics, or density of the telocytes in the atrium/pulmonary veins and AF is potentially speculative, and more studies should be performed before implying it with a reasonable degree of certainty. Copyright © 2018 Elsevier GmbH. All rights reserved.

Incidence, Characteristics, and Clinical Course of Device-Related Thrombus After Watchman Left Atrial Appendage Occlusion Device Implantation in Atrial Fibrillation Patients.

PubMed

Kubo, Shunsuke; Mizutani, Yukiko; Meemook, Krissada; Nakajima, Yoshifumi; Hussaini, Asma; Kar, Saibal

2017-12-11

This study investigated characteristics and clinical impact of device-related thrombus formation after Watchman device implantation in atrial fibrillation (AF) patients. Left atrial appendage occlusion using the Watchman device is an effective alternative to anticoagulation for stroke prevention in AF patients. However, device-related thrombus formation remains an important concern after Watchman implantation. From 2006 to 2014, 119 consecutive AF patients underwent Watchman implantation. Transesophageal echocardiographic (TEE) follow-up was scheduled at 45 days, at 6 months, and at 12 months after the procedure. The incidence, characteristics, and clinical course of device-related thrombus formation detected by TEE were assessed. Follow-up TEE identified thrombus formation on the Watchman device in 4 patients (3.4%). The prevalence of chronic AF was 100% in patients with thrombus, which was higher than that for patients without thrombus (40.0%). Deployed device size was numerically larger in patients with thrombus (29.3 ± 3.8 mm vs. 25.7 ± 3.2 mm, respectively). All patients with thrombus discontinued any of the anticoagulant/antiplatelet therapy which was required under the study protocol. After restarting or continuing warfarin and aspirin therapy, complete resolution of the thrombus was achieved in all patients at subsequent follow-up TEE. Warfarin therapy was discontinued within 6 months for all cases, and there was no thrombus recurrence. The mean follow-up duration was 1,456 ± 546 days, with no death, stroke, or systemic embolization events in patients with thrombus. AF burden, device size, and anticoagulant/antiplatelet regimens can be associated with device-related thrombus after Watchman device implantation. Short-term warfarin therapy was effective, and the clinical outcomes were favorable. Copyright © 2017 American College of Cardiology Foundation. All rights reserved.

Electrogram morphology recurrence patterns during atrial fibrillation.

PubMed

Ng, Jason; Gordon, David; Passman, Rod S; Knight, Bradley P; Arora, Rishi; Goldberger, Jeffrey J

2014-11-01

Traditional mapping of atrial fibrillation (AF) is limited by changing electrogram morphologies and variable cycle lengths. We tested the hypothesis that morphology recurrence plot analysis would identify sites of stable and repeatable electrogram morphology patterns. AF electrograms recorded from left atrial (LA) and right atrial (RA) sites in 19 patients (10 men; mean age 59 ± 10 years) before AF ablation were analyzed. Morphology recurrence plots for each electrogram recording were created by cross-correlation of each automatically detected activation with every other activation in the recording. A recurrence percentage, the percentage of the most common morphology, and the mean cycle length of activations with the most recurrent morphology were computed. The morphology recurrence plots commonly showed checkerboard patterns of alternating high and low cross-correlation values, indicating periodic recurrences in morphologies. The mean recurrence percentage for all sites and all patients was 38 ± 25%. The highest recurrence percentage per patient averaged 83 ± 17%. The highest recurrence percentage was located in the RA in 5 patients and in the LA in 14 patients. Patients with sites of shortest mean cycle length of activations with the most recurrent morphology in the LA and RA had ablation failure rates of 25% and 100%, respectively (hazard ratio 4.95; P = .05). A new technique to characterize electrogram morphology recurrence demonstrated that there is a distribution of sites with high and low repeatability of electrogram morphologies. Sites with rapid activation of highly repetitive morphology patterns may be critical to sustaining AF. Further testing of this approach to map and ablate AF sources is warranted. Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Screening strategies for atrial fibrillation: a systematic review and cost-effectiveness analysis.

PubMed

Welton, Nicky J; McAleenan, Alexandra; Thom, Howard Hz; Davies, Philippa; Hollingworth, Will; Higgins, Julian Pt; Okoli, George; Sterne, Jonathan Ac; Feder, Gene; Eaton, Diane; Hingorani, Aroon; Fawsitt, Christopher; Lobban, Trudie; Bryden, Peter; Richards, Alison; Sofat, Reecha

2017-05-01

Atrial fibrillation (AF) is a common cardiac arrhythmia that increases the risk of thromboembolic events. Anticoagulation therapy to prevent AF-related stroke has been shown to be cost-effective. A national screening programme for AF may prevent AF-related events, but would involve a substantial investment of NHS resources. To conduct a systematic review of the diagnostic test accuracy (DTA) of screening tests for AF, update a systematic review of comparative studies evaluating screening strategies for AF, develop an economic model to compare the cost-effectiveness of different screening strategies and review observational studies of AF screening to provide inputs to the model. Systematic review, meta-analysis and cost-effectiveness analysis. Primary care. Adults. Screening strategies, defined by screening test, age at initial and final screens, screening interval and format of screening {systematic opportunistic screening [individuals offered screening if they consult with their general practitioner (GP)] or systematic population screening (when all eligible individuals are invited to screening)}. Sensitivity, specificity and diagnostic odds ratios; the odds ratio of detecting new AF cases compared with no screening; and the mean incremental net benefit compared with no screening. Two reviewers screened the search results, extracted data and assessed the risk of bias. A DTA meta-analysis was perfomed, and a decision tree and Markov model was used to evaluate the cost-effectiveness of the screening strategies. Diagnostic test accuracy depended on the screening test and how it was interpreted. In general, the screening tests identified in our review had high sensitivity (> 0.9). Systematic population and systematic opportunistic screening strategies were found to be similarly effective, with an estimated 170 individuals needed to be screened to detect one additional AF case compared with no screening. Systematic opportunistic screening was more likely to be cost-effective than systematic population screening, as long as the uptake of opportunistic screening observed in randomised controlled trials translates to practice. Modified blood pressure monitors, photoplethysmography or nurse pulse palpation were more likely to be cost-effective than other screening tests. A screening strategy with an initial screening age of 65 years and repeated screens every 5 years until age 80 years was likely to be cost-effective, provided that compliance with treatment does not decline with increasing age. A national screening programme for AF is likely to represent a cost-effective use of resources. Systematic opportunistic screening is more likely to be cost-effective than systematic population screening. Nurse pulse palpation or modified blood pressure monitors would be appropriate screening tests, with confirmation by diagnostic 12-lead electrocardiography interpreted by a trained GP, with referral to a specialist in the case of an unclear diagnosis. Implementation strategies to operationalise uptake of systematic opportunistic screening in primary care should accompany any screening recommendations. Many inputs for the economic model relied on a single trial [the Screening for Atrial Fibrillation in the Elderly (SAFE) study] and DTA results were based on a few studies at high risk of bias/of low applicability. Comparative studies measuring long-term outcomes of screening strategies and DTA studies for new, emerging technologies and to replicate the results for photoplethysmography and GP interpretation of 12-lead electrocardiography in a screening population. This study is registered as PROSPERO CRD42014013739. The National Institute for Health Research Health Technology Assessment programme.

Genome-wide screening identifies a KCNIP1 copy number variant as a genetic predictor for atrial fibrillation

PubMed Central

Tsai, Chia-Ti; Hsieh, Chia-Shan; Chang, Sheng-Nan; Chuang, Eric Y.; Ueng, Kwo-Chang; Tsai, Chin-Feng; Lin, Tsung-Hsien; Wu, Cho-Kai; Lee, Jen-Kuang; Lin, Lian-Yu; Wang, Yi-Chih; Yu, Chih-Chieh; Lai, Ling-Ping; Tseng, Chuen-Den; Hwang, Juey-Jen; Chiang, Fu-Tien; Lin, Jiunn-Lee

2016-01-01

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. Previous genome-wide association studies had identified single-nucleotide polymorphisms in several genomic regions to be associated with AF. In human genome, copy number variations (CNVs) are known to contribute to disease susceptibility. Using a genome-wide multistage approach to identify AF susceptibility CNVs, we here show a common 4,470-bp diallelic CNV in the first intron of potassium interacting channel 1 gene (KCNIP1) is strongly associated with AF in Taiwanese populations (odds ratio=2.27 for insertion allele; P=6.23 × 10−24). KCNIP1 insertion is associated with higher KCNIP1 mRNA expression. KCNIP1-encoded protein potassium interacting channel 1 (KCHIP1) is physically associated with potassium Kv channels and modulates atrial transient outward current in cardiac myocytes. Overexpression of KCNIP1 results in inducible AF in zebrafish. In conclusions, a common CNV in KCNIP1 gene is a genetic predictor of AF risk possibly pointing to a functional pathway. PMID:26831368

Atrial Fibrillation in Athletes: A Lesson in the Virtue of Moderation.

PubMed

Estes, N A Mark; Madias, Christopher

2017-09-01

Although the cardiovascular benefits of moderate exercise are well established, there is growing epidemiological support for the notion that high-intensity endurance athletics increases the risk of atrial fibrillation (AF). There are many gaps in evidence related to epidemiology and mechanisms of AF in endurance athletes. The proposed pathophysiological mechanisms include alterations of autonomic tone, electrical remodeling, anatomical remodeling, fibrosis, and inflammation. Clinical management of the athlete with AF often includes a period of decreased frequency, intensity, and duration of exercise with assessment for improvement in AF recurrence. Based on symptoms, a strategy of rate or rhythm control should be selected; however, due to side effects and intolerance of medications, ablation may be a preferred approach. The risks and benefits of anticoagulation for stroke prevention must be carefully assessed in the athlete with AF. All patients should be encouraged to be physically active with moderation; however, men should be advised of the higher risk of AF with long-term, high-intensity endurance training. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Atrial fibrillation surgery in nonrheumatic mitral valve disease.

PubMed

Gillinov, Marc

2007-12-01

Atrial fibrillation (AF) is present in 30-50% of patients presenting for mitral valve surgery. If left untreated, AF in these patients is associated with increased morbidity and, possibly, increased mortality. Therefore, concomitant management of the arrhythmia is indicated in most mitral valve patients with preexisting AF. The cut-and-sew Cox-Maze III procedure is extremely effective, eliminating AF in 80-95%; however, it has been supplanted by newer operations that rely upon alternate energy sources to create lines of conduction block. Early and midterm results are good with a variety of technologies. Choice of lesion set remains a matter of debate, but success of ablation appears to be enhanced by a biatrial lesion set and exceeds 90% in some series. Targeted areas for improvement in combined mitral valve surgery and AF ablation include acceptance of uniform standards for reporting results, development of improved technology for ablation and intraoperative assessment, and creation of instrumentation that facilitates minimally invasive approaches.

Using new non-invasive quick method to detect Borrelia Burgdorferi (B.B.) infection from specific parts of the heart in "seemingly normal" ECGs, and from the ECGs of Atrial Fibrillation (AF), a majority of AF ECGs are found to have: 1) Significant B.B. infection, 2) Markedly increased ANP, 3) Increased Cardiac Troponin I & 4) Markedly reduced Taurine. These 4 factors were mainly localized at infected areas of the SA node area, R-&L-Atria & pulmonary veins at the L-atrium.

PubMed

Omura, Yoshiaki; Lu, Dominic; Jones, Marilyn K; Nihrane, Abdallah; Duvvi, Harsha; Yapor, Dario; Shimotsuura, Yasuhiro; Ohki, Motomu

2015-01-01

Lyme disease is found in a majority of people we tested. Once Borrelia Burgdorferi (B.B.) spirochete enters human body, it not only causes pain by infecting joints, but it also often enters the brain and the heart. Infection of brain can be quickly detected from the pupil and infection of the heart by ECGs non-invasively. By evaluating recorded ECGs of atrial fibrillation (AF), using U.S. patented non-invasive highly sensitive electromagnetic field (EMF) resonance phenomenon between 2 identical molecules or between a molecule and its antibody, we examined 25 different AF patients' ECGs and found the majority of them suffer from various degrees of B.B. spirochete infection in SA node areas, also in the right & left atria, and pulmonary vein near and around its junction at left atrium & lesser degrees of infection at the AV node & His Bundle. When B.B. infection reaches over 224-600ng or higher at these areas, AF often appears in the majority of all AF analyzed. In order to develop AF, the 4 abnormal factors must be present simultaneously: 1) B.B. infection must be increased to 224-600ng or higher, 2) Atrial Natriuretic Peptide (ANP) must be markedly reduced from normal value of less than 4ng to over 100-400ng, 3) A significant increase of Cardiac Troponin I from normal value of less than 3ng to over 12ng and 4) Taurine must also be markedly reduced from normal value of 4-6ng to 0.25ng. These 4 changes were mainly found only at infected sites of the SA node area, both atria and between the end of the T wave & the beginning of the SA node area, which corresponds to U waves at recorded ECG. Origin of the U wave is mainly due to abnormal electrical potential of pulmonary vein at L-atrium. If all 4 factors do not occur at the infection site, no AF will develop. In seemingly normal ECGs, if using this method, one can detect invisible B.B. infection in early stages. Long before AF appears, AF can be prevented by improved treatment with Amoxicillin 500ng 3 times/day + Taurine 175mg x 3 times/day, with or without EPA 180 mg & DHA 120 mg, to avoid serious current limitations in the use of Doxycycline 100 mg 2 times/day, for 4 weeks.

Use of preoperative CHA2 DS2 -VASc score to predict the risk of atrial fibrillation after cardiothoracic surgery: a nested case-control study from the Atrial Fibrillation Suppression Trials (AFIST) I, II, and III.

PubMed

Baker, William L; Coleman, Craig I; White, C Michael; Kluger, Jeffrey

2013-05-01

To evaluate whether the preoperative CHA2 DS2 -VASc score predicts the risk of atrial fibrillation (AF) after cardiothoracic surgery (CTS). Retrospective, nested case-control study. A total of 560 patients undergoing coronary artery bypass grafting and/or valvular surgery from the Atrial Fibrillation Suppression Trials I, II, and III. All variables showing a univariate association (p≤0.20) with AF occurrence were entered into a backward stepwise multivariate logistic regression analysis to control for potential confounders and to calculate adjusted odds ratios (AORs) with 95% confidence intervals (CIs). The population was age 67.8 ± 8.6 (mean ± SD) years and 77.1% male, with CHA2 DS2 -VASc scores of 0-1 (low) in 34 patients (6.1%), 2-3 (medium) in 261 patients (46.6%), and more than 3 (high) in 265 patients (47.3%). Post-CTS AF occurred in 177 patients (31.6%), with 27%, 23%, and 41% in the low-, medium-, and high-CHA2 DS2 -VASc score groups, respectively. The high-score group had a 2.3-fold increased odds of developing AF versus the medium-score group (p<0.0001). The differences between the high- and medium-score groups when each group was compared with the low-score group were not statistically significant. On the multivariate logistic regression analysis, CHA2 DS2 -VASc score was associated with development of AF (AOR 1.20, 95% CI 1.06-1.36). Increasing CHA2 DS2 -VASc score was an independent predictor for the development of post-CTS AF, with patients in the high-score group having the highest overall incidence. © 2013 Pharmacotherapy Publications, Inc.

Improvements In AF Ablation Outcome Will Be Based More On Technological Advancement Versus Mechanistic Understanding.

PubMed

Jiang Md, Chen-Yang; Jiang Ms, Ru-Hong

2014-01-01

Atrial fibrillation (AF) is one of the most common cardiac arrhythmias. Catheter ablation has proven more effective than antiarrhythmic drugs in preventing clinical recurrence of AF, however long-term outcome remains unsatisfactory. Ablation strategies have evolved based on progress in mechanistic understanding, and technologies have advanced continuously. This article reviews current mechanistic concepts and technological advancements in AF treatment, and summarizes their impact on improvement of AF ablation outcome.

Characterization of atrial fibrillation adverse events reported in ibrutinib randomized controlled registration trials.

PubMed

Brown, Jennifer R; Moslehi, Javid; O'Brien, Susan; Ghia, Paolo; Hillmen, Peter; Cymbalista, Florence; Shanafelt, Tait D; Fraser, Graeme; Rule, Simon; Kipps, Thomas J; Coutre, Steven; Dilhuydy, Marie-Sarah; Cramer, Paula; Tedeschi, Alessandra; Jaeger, Ulrich; Dreyling, Martin; Byrd, John C; Howes, Angela; Todd, Michael; Vermeulen, Jessica; James, Danelle F; Clow, Fong; Styles, Lori; Valentino, Rudy; Wildgust, Mark; Mahler, Michelle; Burger, Jan A

2017-10-01

The first-in-class Bruton's tyrosine kinase inhibitor ibrutinib has proven clinical benefit in B-cell malignancies; however, atrial fibrillation (AF) has been reported in 6-16% of ibrutinib patients. We pooled data from 1505 chronic lymphocytic leukemia and mantle cell lymphoma patients enrolled in four large, randomized, controlled studies to characterize AF with ibrutinib and its management. AF incidence was 6.5% [95% Confidence Interval (CI): 4.8, 8.5] for ibrutinib at 16.6-months versus 1.6% (95%CI: 0.8, 2.8) for comparator and 10.4% (95%CI: 8.4, 12.9) at the 36-month follow up; estimated cumulative incidence: 13.8% (95%CI: 11.2, 16.8). Ibrutinib treatment, prior history of AF and age 65 years or over were independent risk factors for AF. Multiple AF events were more common with ibrutinib (44.9%; comparator, 16.7%) among patients with AF. Most (85.7%) patients with AF did not discontinue ibrutinib, and more than half received common anticoagulant/antiplatelet medications on study. Low-grade bleeds were more frequent with ibrutinib, but serious bleeds were uncommon (ibrutinib, 2.9%; comparator, 2.0%). Although the AF rate among older non-trial patients with comorbidities is likely underestimated by this dataset, these results suggest that AF among clinical trial patients is generally manageable without ibrutinib discontinuation ( clinicaltrials.gov identifier: 01578707, 01722487, 01611090, 01646021 ). Copyright© 2017 Ferrata Storti Foundation.

Characterization of atrial fibrillation adverse events reported in ibrutinib randomized controlled registration trials

PubMed Central

Brown, Jennifer R.; Moslehi, Javid; O’Brien, Susan; Ghia, Paolo; Hillmen, Peter; Cymbalista, Florence; Shanafelt, Tait D.; Fraser, Graeme; Rule, Simon; Kipps, Thomas J.; Coutre, Steven; Dilhuydy, Marie-Sarah; Cramer, Paula; Tedeschi, Alessandra; Jaeger, Ulrich; Dreyling, Martin; Byrd, John C.; Howes, Angela; Todd, Michael; Vermeulen, Jessica; James, Danelle F.; Clow, Fong; Styles, Lori; Valentino, Rudy; Wildgust, Mark; Mahler, Michelle; Burger, Jan A.

2017-01-01

The first-in-class Bruton’s tyrosine kinase inhibitor ibrutinib has proven clinical benefit in B-cell malignancies; however, atrial fibrillation (AF) has been reported in 6–16% of ibrutinib patients. We pooled data from 1505 chronic lymphocytic leukemia and mantle cell lymphoma patients enrolled in four large, randomized, controlled studies to characterize AF with ibrutinib and its management. AF incidence was 6.5% [95% Confidence Interval (CI): 4.8, 8.5] for ibrutinib at 16.6-months versus 1.6% (95%CI: 0.8, 2.8) for comparator and 10.4% (95%CI: 8.4, 12.9) at the 36-month follow up; estimated cumulative incidence: 13.8% (95%CI: 11.2, 16.8). Ibrutinib treatment, prior history of AF and age 65 years or over were independent risk factors for AF. Multiple AF events were more common with ibrutinib (44.9%; comparator, 16.7%) among patients with AF. Most (85.7%) patients with AF did not discontinue ibrutinib, and more than half received common anticoagulant/antiplatelet medications on study. Low-grade bleeds were more frequent with ibrutinib, but serious bleeds were uncommon (ibrutinib, 2.9%; comparator, 2.0%). Although the AF rate among older non-trial patients with comorbidities is likely underestimated by this dataset, these results suggest that AF among clinical trial patients is generally manageable without ibrutinib discontinuation (clinicaltrials.gov identifier: 01578707, 01722487, 01611090, 01646021). PMID:28751558

Left atrial structure and function in atrial fibrillation: ENGAGE AF-TIMI 48

PubMed Central

Gupta, Deepak K.; Shah, Amil M.; Giugliano, Robert P.; Ruff, Christian T.; Antman, Elliott M.; Grip, Laura T.; Deenadayalu, Naveen; Hoffman, Elaine; Patel, Indravadan; Shi, Minggao; Mercuri, Michele; Mitrovic, Veselin; Braunwald, Eugene; Solomon, Scott D.

2014-01-01

Aims The complex relationship between left atrial (LA) structure and function, electrical burden of atrial fibrillation (AF) and stroke risk is not well understood. We aimed to describe LA structure and function in AF. Methods and results Left atrial structure and function was assessed in 971 subjects enrolled in the echocardiographic substudy of ENGAGE AF-TIMI 48. Left atrial size, emptying fraction (LAEF), and contractile function were compared across AF types (paroxysmal, persistent, or permanent) and CHADS2 scores as an estimate of stroke risk. The majority of AF patients (55%) had both LA enlargement and reduced LAEF, with an inverse relationship between LA size and LAEF (R = −0.57, P < 0.001). With an increasing electrical burden of AF and higher CHADS2 scores, LA size increased and LAEF declined. Moreover, 19% of AF subjects had impaired LAEF despite normal LA size, and LA contractile dysfunction was present even among the subset of AF subjects in sinus rhythm at the time of echocardiography. Conclusions In a contemporary AF population, LA structure and function were increasingly abnormal with a greater electrical burden of AF and higher stroke risk estimated by the CHADS2 score. Moreover, LA dysfunction was present despite normal LA size and sinus rhythm, suggesting that the assessment of LA function may add important incremental information in the evaluation of AF patients. Clinical Trial Registration: http://www.clinicaltrials.gov; ID = NCT00781391. PMID:24302269

The why, when and how to test for obstructive sleep apnea in patients with atrial fibrillation.

PubMed

Desteghe, Lien; Hendriks, Jeroen M L; McEvoy, R Doug; Chai-Coetzer, Ching Li; Dendale, Paul; Sanders, Prashanthan; Heidbuchel, Hein; Linz, Dominik

2018-04-12

Sleep apnea is associated with increased cardiovascular risk and may be important in atrial fibrillation (AF) management. It is present in up to 62% of the AF population and is highly under-recognized and underdiagnosed. Obstructive sleep apnea (OSA) is strongly associated with AF and non-randomized trials have shown that its treatment can help to reduce AF recurrences and maintain sinus rhythm. The 2016 European Society of Cardiology guidelines for the management of AF recommend that AF patients should be questioned regarding the symptoms of OSA and that OSA-treatment should be optimized to improve AF treatment results. However, strategies on how to implement OSA testing in the standard work-up of AF patients are not provided in the guidelines. Additionally, overnight OSA monitoring rather than interrogation for OSA-related clinical signs alone may be necessary to reliably identify OSA in the majority of AF patients. This review summarizes the available clinical data on OSA in AF patients, and discusses the following key questions: Why and When is testing for OSA needed in AF patients? How and Where should it be performed and coordinated? and Who should test for OSA? To implement OSA testing in a cardiology or electrophysiology clinic, we propose a multidisciplinary integrated care approach based on a chronic care model. We describe the tools, infrastructure and coordination needed to test for OSA in the standard workup of patients with symptomatic AF prior to the initiation of directed invasive or pharmacological rhythm control management.

State-of-the-art and emerging technologies for atrial fibrillation ablation.

PubMed

Dewire, Jane; Calkins, Hugh

2010-03-01

Catheter ablation is an important treatment modality for patients with atrial fibrillation (AF). Although the superiority of catheter ablation over antiarrhythmic drug therapy has been demonstrated in middle-aged patients with paroxysmal AF, the role the procedure in other patient subgroups-particularly those with long-standing persistent AF-has not been well defined. Furthermore, although AF ablation can be performed with reasonable efficacy and safety by experienced operators, long-term success rates for single procedures are suboptimal. Fortunately, extensive ongoing research will improve our understanding of the mechanisms of AF, and considerable funds are being invested in developing new ablation technologies to improve patient outcomes. These technologies include ablation catheters designed to electrically isolate the pulmonary veins with improved safety, efficacy, and speed, catheters designed to deliver radiofrequency energy with improved precision, robotic systems to address the technological demands of the procedure, improved imaging and electrical mapping systems, and MRI-guided ablation strategies. The tools, technologies, and techniques that will ultimately stand the test of time and become the standard approach to AF ablation in the future remain unclear. However, technological advances are sure to result in the necessary improvements in the safety and efficacy of AF ablation procedures.

Surgical RF ablation of atrial fibrillation in patients undergoing mitral valve repair for Barlow disease.

PubMed

Rostagno, Carlo; Droandi, G; Gelsomino, S; Carone, E; Gensini, G F; Stefàno, P L

2013-01-01

At present, limited experience exists on the treatment of atrial fibrillation (AF) in patients undergoing mitral valve repair (MVR) for Barlow disease. The aim of this investigation was to prospectively evaluate the radiofrequency ablation of AF in patients undergoing MVR for severe regurgitation due to Barlow disease. From January 1, 2007 to December 31, 2010, out of 85 consecutive patients with Barlow disease, 27 with AF underwent RF ablation associated with MVR. They were examined every 4 months in the first year after surgery and thereafter twice yearly. At follow-up, AF was observed in 4/25 (16.0%). NYHA (New York Heart Association) functional class improved significantly, with no patients in class III or IV (before surgery, 81.5% had been). Otherwise, among 58 patients in sinus rhythm, 6 (11%) developed AF during follow-up. No clinical or echocardiographic predictive factor was found in this subgroup. Results from our investigation suggest that radiofrequency ablation of AF in patients with Barlow disease undergoing MVR for severe regurgitation is effective and should be considered in every patient with Barlow disease and AF undergoing valve surgical repair. Copyright © 2013 S. Karger AG, Basel.

Rivaroxaban in patients with atrial fibrillation: from ROCKET AF to everyday practice.

PubMed

Barón-Esquivias, Gonzalo; Marín, Francisco; Sanmartín Fernandez, Marcelo

2017-05-01

Registries and non-interventional studies offer relevant and complementary information to clinical trials, since they have a high external validity. Areas covered: The information regarding the efficacy and safety of rivaroxaban compared with warfarin, or rivaroxaban alone in clinical practice was reviewed in this manuscript. For this purpose, a search on MEDLINE and EMBASE databases was performed. The MEDLINE and EMBASE search included both medical subject headings (MeSH) and keywords including: atrial fibrillation (AF) OR warfarin OR clinical practice OR ROCKET AF AND rivaroxaban. Case reports were not considered. Expert commentary: In ROCKET AF, rivaroxaban was at least as effective as warfarin for the prevention of stroke in patients with nonvalvular AF at high risk of stroke, but, importantly, with a lesser risk of intracranial, critical and fatal bleedings. A number of observational comparative and non-comparative studies, with more than 60,000 patients included treated with rivaroxaban, have analyzed the efficacy and safety of rivaroxaban in real-life patients with AF in different clinical settings. These studies have shown that in clinical practice, rates of stroke and major bleeding were consistently lower than those reported in ROCKET AF, likely due to the lower thromboembolic and bleeding risk observed in these patients.

Standardized Prevalence Ratios for Atrial Fibrillation in Adult Dialysis Patients in Japan.

PubMed

Ohsawa, Masaki; Tanno, Kozo; Okamura, Tomonori; Yonekura, Yuki; Kato, Karen; Fujishima, Yosuke; Obara, Wataru; Abe, Takaya; Itai, Kazuyoshi; Ogasawara, Kuniaki; Omama, Shinichi; Turin, Tanvir Chowdhury; Miyamatsu, Naomi; Ishibashi, Yasuhiro; Morino, Yoshihiro; Itoh, Tomonori; Onoda, Toshiyuki; Kuribayashi, Toru; Makita, Shinji; Yoshida, Yuki; Nakamura, Motoyuki; Tanaka, Fumitaka; Ohta, Mutsuko; Sakata, Kiyomi; Okayama, Akira

2016-05-05

While it is assumed that dialysis patients in Japan have a higher prevalence of atrial fibrillation (AF) than the general population, the magnitude of this difference is not known. Standardized prevalence ratios (SPRs) for AF in dialysis patients (n = 1510) were calculated compared to data from the general population (n = 26 454) living in the same area. The prevalences of AF were 3.8% and 1.6% in dialysis patients and the general population, respectively. In male subjects, these respective values were 4.9% and 3.3%, and in female subjects they were 1.6% and 0.6%. The SPRs for AF were 2.53 (95% confidence interval [CI], 1.88-3.19) in all dialysis patients, 1.80 (95% CI, 1.30-2.29) in male dialysis patients, and 2.13 (95% CI, 0.66-3.61) in female dialysis patients. The prevalence of AF in dialysis patients was twice that in the population-based controls. Since AF strongly contributes to a higher risk of cardiovascular mortality and morbidity in the general population, further longitudinal studies should be conducted regarding the risk of several outcomes attributable to AF among Japanese dialysis patients.

Effects of enhanced pacing modalities on health care resource utilization and costs in bradycardia patients: An analysis of the randomized MINERVA trial.

PubMed

Boriani, Giuseppe; Manolis, Antonis S; Tukkie, Raymond; Mont, Lluis; Pürerfellner, Helmut; Santini, Massimo; Inama, Giuseppe; Serra, Paolo; Gulizia, Michele; Samoilenko, Igor Vasilyevich; Wolff, Claudia; Holbrook, Reece; Gavazza, Federica; Padeletti, Luigi

2015-06-01

Many patients who suffer from bradycardia and need cardiac pacing also have atrial fibrillation (AF). New pacemaker algorithms, such as atrial preventive pacing and atrial antitachycardia pacing (DDDRP) and managed ventricular pacing (MVP), have been specifically designed to reduce AF occurrence and duration and to minimize the detrimental effects of right ventricular pacing. The randomized MINimizE Right Ventricular pacing to prevent Atrial fibrillation and heart failure trial established that DDDRP + MVP pacing modality reduced permanent AF in bradycardia patients as compared with standard dual-chamber pacing (DDDR). The aim of this study was to estimate the cost savings due to lower AF-related health care utilization events based on health care costs from the United States and the European Union. Dual-chamber pacemaker patients with a history of paroxysmal or persistent AF were randomly assigned to receive DDDR (n = 385) or the advanced features (DDDRP + MVP; n = 383). We used published health care costs from the United States and the European Union (Italy, Spain, and the United Kingdom) to estimate the costs associated with AF-related hospitalizations and emergency visits. The rate of AF-related hospitalizations was significantly lower in the DDDRP + MVP group than in the conventional pacemaker group (DDDR group; 42% reduction; incidence rate ratio 0.58). Similarly, a significant reduction of 68% was observed for AF-related emergency department visits (incidence rate ratio 0.32; P < .001). As a consequence, DDDRP + MVP could potentially reduce health care costs by 40%-44%. Over a ten-year period, the cost savings per 100 patients ranged from $35,702 in the United Kingdom to $121,831 in the United States. New pacing algorithms such as DDDRP + MVP used in the MINimizE Right Ventricular pacing to prevent Atrial fibrillation and heart failure trial successfully reduced AF-related health care utilization, resulting in significant cost savings to payers. Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

A genotype-directed comparative effectiveness trial of Bucindolol and metoprolol succinate for prevention of symptomatic atrial fibrillation/atrial flutter in patients with heart failure: Rationale and design of the GENETIC-AF trial.

PubMed

Piccini, Jonathan P; Connolly, Stuart J; Abraham, William T; Healey, Jeff S; Steinberg, Benjamin A; Al-Khalidi, Hussein R; Dignacco, Patricia; van Veldhuisen, Dirk J; Sauer, William H; White, Michel; Wilton, Stephen B; Anand, Inder S; Dufton, Christopher; Marshall, Debra A; Aleong, Ryan G; Davis, Gordon W; Clark, Richard L; Emery, Laura L; Bristow, Michael R

2018-05-01

Few therapies are available for the safe and effective treatment of atrial fibrillation (AF) in patients with heart failure. Bucindolol is a non-selective beta-blocker with mild vasodilator activity previously found to have accentuated antiarrhythmic effects and increased efficacy for preventing heart failure events in patients homozygous for the major allele of the ADRB1 Arg389Gly polymorphism (ADRB1 Arg389Arg genotype). The safety and efficacy of bucindolol for the prevention of AF or atrial flutter (AFL) in these patients has not been proven in randomized trials. The Genotype-Directed Comparative Effectiveness Trial of Bucindolol and Metoprolol Succinate for Prevention of Symptomatic Atrial Fibrillation/Atrial Flutter in Patients with Heart Failure (GENETIC-AF) trial is a multicenter, randomized, double-blinded "seamless" phase 2B/3 trial of bucindolol hydrochloride versus metoprolol succinate, for the prevention of symptomatic AF/AFL in patients with reduced ejection fraction heart failure (HFrEF). Patients with pre-existing HFrEF and recent history of symptomatic AF are eligible for enrollment and genotype screening, and if they are ADRB1 Arg389Arg, eligible for randomization. A total of approximately 200 patients will comprise the phase 2B component and if pre-trial assumptions are met, 620 patients will be randomized at approximately 135 sites to form the Phase 3 population. The primary endpoint is the time to recurrence of symptomatic AF/AFL or mortality over a 24-week follow-up period, and the trial will continue until 330 primary endpoints have occurred. GENETIC-AF is the first randomized trial of pharmacogenetic guided rhythm control, and will test the safety and efficacy of bucindolol compared with metoprolol succinate for the prevention of recurrent symptomatic AF/AFL in patients with HFrEF and an ADRB1 Arg389Arg genotype. (ClinicalTrials.govNCT01970501). Copyright © 2017 Elsevier Inc. All rights reserved.

Serial measures of cardiac troponin T levels by a highly sensitive assay and incident atrial fibrillation in a prospective cohort of ambulatory older adults.

PubMed

Hussein, Ayman A; Bartz, Traci M; Gottdiener, John S; Sotoodehnia, Nona; Heckbert, Susan R; Lloyd-Jones, Donald; Kizer, Jorge R; Christenson, Robert; Wazni, Oussama; deFilippi, Christopher

2015-05-01

Various mechanisms in cardiac remodeling related to atrial fibrillation (AF) lead to elevated circulating cardiac troponin levels, but little is known about such elevations upstream to AF onset. The purpose of this study was to study the association between circulating troponin levels as assessed by a highly sensitive cardiac troponin T (hs-cTnT) assay and incident atrial fibrillation (AF). In a large prospective cohort of ambulatory older adults [the Cardiovascular Health Study (CHS)], hs-cTnT levels were measured in sera that were collected at enrollment from 4262 participants without AF (2871 with follow-up measurements). Incident AF was identified by electrocardiograms during CHS visits, hospital discharge diagnoses, and Medicare files, including outpatient and physician claims diagnoses. Over median follow-up of 11.2 years (interquartile range 6.1-16.5), 1363 participants (32.0%) developed AF. Higher baseline levels of hs-cTnT were associated with incident AF in covariate-adjusted analyses accounting for demographics, traditional risk factors, and incident heart failure in time-dependent analyzes (hazard ratio for 3rd tertile vs undetectable 1.75, 95% confidence interval 1.48-2.08). This association was statistically significant in analyses that additionally adjusted for biomarkers of inflammation and hemodynamic strain (hazard ratio for 3rd tertile vs undetectable 1.38, 95% confidence interval 1.16-1.65). Significant associations were also found when hs-cTnT levels were treated as a continuous variable and when examining change from baseline of hs-cTnT levels and incident AF. The findings show a significant association of circulating troponin levels in ambulatory older adults with incident AF beyond that of traditional risk factors, incident heart failure, and biomarkers of inflammation and hemodynamic strain. Copyright © 2015 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Angiotensin converting enzyme 2 activity and human atrial fibrillation: increased plasma angiotensin converting enzyme 2 activity is associated with atrial fibrillation and more advanced left atrial structural remodelling.

PubMed

Walters, Tomos E; Kalman, Jonathan M; Patel, Sheila K; Mearns, Megan; Velkoska, Elena; Burrell, Louise M

2017-08-01

Angiotensin converting enzyme 2 (ACE2) is an integral membrane protein whose main action is to degrade angiotensin II. Plasma ACE2 activity is increased in various cardiovascular diseases. We aimed to determine the relationship between plasma ACE2 activity and human atrial fibrillation (AF), and in particular its relationship to left atrial (LA) structural remodelling. One hundred and three participants from a tertiary arrhythmia centre, including 58 with paroxysmal AF (PAF), 20 with persistent AF (PersAF), and 25 controls, underwent clinical evaluation, echocardiographic analysis, and measurement of plasma ACE2 activity. A subgroup of 20 participants underwent invasive LA electroanatomic mapping. Plasma ACE2 activity levels were increased in AF [control 13.3 (9.5-22.3) pmol/min/mL; PAF 16.9 (9.7-27.3) pmol/min/mL; PersAF 22.8 (13.7-33.4) pmol/min/mL, P = 0.006]. Elevated plasma ACE2 was associated with older age, male gender, hypertension and vascular disease, elevated left ventricular (LV) mass, impaired LV diastolic function and advanced atrial disease (P < 0.05 for all). Independent predictors of elevated plasma ACE2 activity were AF (P = 0.04) and vascular disease (P < 0.01). There was a significant relationship between elevated ACE2 activity and low mean LA bipolar voltage (adjusted R2 = 0.22, P = 0.03), a high proportion of complex fractionated electrograms (R2 = 0.32, P = 0.009) and a long LA activation time (R2 = 0.20, P = 0.04). Plasma ACE2 activity is elevated in human AF. Both AF and vascular disease predict elevated plasma ACE2 activity, and elevated plasma ACE2 is significantly associated with more advanced LA structural remodelling. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

Atrial fibrillation: stroke prevention in focus.

PubMed

Ferguson, Caleb; Inglis, Sally C; Newton, Phillip J; Middleton, Sandy; Macdonald, Peter S; Davidson, Patricia M

2014-05-01

Atrial fibrillation (AF) is a common arrhythmia and a risk factor for stroke and other, adverse events. Internationally there have been recent advancements in the therapies available for, stroke prevention in AF. Nurses will care for individuals with AF across a variety of primary and acute, care settings and should be familiar with evidence based therapies. This paper provides a review of the epidemiology of AF and stroke, stroke and bleeding risk, assessment tools and evidence based treatments for the prevention of stroke in AF including the use of, novel anti-thrombin agents. A review of key databases was conducted from 2002 to 2012 using the key search terms 'atrial, fibrillation' 'anticoagulation' 'risk assessment' and 'clinical management'. The following electronic, databases were searched: CINAHL, Medline, Scopus, the Cochrane Library and Google Scholar., Reference lists were manually hand searched. Key clinical guidelines from National Institute for, Clinical Excellence (NICE, UK), American Heart Association (AHA, USA), American College of Cardiology, (ACC, USA) and the European Society of Cardiology (ESC) and key government policy documents were, also included. Articles were included in the review if they addressed nursing management with a focus, on Australia. Many treatment options exist for AF. Best practice guidelines make a variety of, recommendations which include cardioversion, ablation, pulmonary vein isolation, pharmacological, agents for rate or rhythm control approaches, and antithrombotic therapy (including anticoagulation, and antiplatelet therapy). Treatment should be patient centred and individualised based upon, persistency of the rhythm, causal nature, risk and co-morbid conditions. AF is a common and burdensome condition where treatment is complex and not without, risk. Nurses will encounter individuals with AF across a variety of primary and acute care areas, understanding the risk of AF and appropriate therapies is important across all care settings. Treatment, must be individually tailored to the needs of the patient and balanced with the best available evidence. Copyright © 2013 Australian College of Critical Care Nurses Ltd. Published by Elsevier Ltd. All rights reserved.

Prevention of atrial fibrillation and inflammatory response after on-pump coronary artery bypass using different statin dosages: a randomized, controlled trial.

PubMed

Pierri, Michele Danilo; Crescenzi, Giuseppe; Zingaro, Carlo; D'Alfonso, Alessandro; Capestro, Filippo; Scocco, Vitangelo; Brugia, Marina; Torracca, Lucia

2016-07-01

This randomized controlled trial aimed to evaluate the effects of seven-day preoperative treatment with two different dosages of atorvastatin on the incidence of postoperative atrial fibrillation (POAF) and release of inflammatory markers such as high-sensitive C-reactive protein (hsCRP) and interleukin-6 in patients undergoing elective first-time on-pump coronary artery bypass grafting (CABG). The cohort study comprised 212 consecutive patients, already taking statins, who underwent elective first-time CABG with cardiopulmonary bypass without history of atrial fibrillation (AF). Patients were randomly divided into two groups: those who received atorvastatin 40 mg (TOR40 group, 111 patients) and those who received 80 mg (TOR80 group, 101 patients) once a day for 7 days before the planned operation. The primary endpoint was the incidence of AF. The secondary endpoints were the postoperative variations of inflammatory markers, hospital length of stay, and the incidence of major adverse cardiac and clinical events. A total of 26 patients (23.6 %) pretreated with atorvastatin 40 mg and 16 (15.8 %) patients pretreated with atorvastatin 80 mg had postoperative AF but the difference did not reach the statistical significance (p = 0.157). Median values of interleukin-6 and hsCRP at 12 and 24 h did not have differences between the two groups. No statistically significant differences in the other secondary endpoints were detected. According to our result, 7-day preoperative treatment with a high dose of atorvastatin is associated with a trend to a decrease in the incidence of POAF compared with treatment at a lower dose, although it does not impact on the level of inflammatory markers. European Clinical Trials Database (EudraCT: 2006-005757-30).

Quality of life assessment in the randomized PROTECT AF (Percutaneous Closure of the Left Atrial Appendage Versus Warfarin Therapy for Prevention of Stroke in Patients With Atrial Fibrillation) trial of patients at risk for stroke with nonvalvular atrial fibrillation.

PubMed

Alli, Oluseun; Doshi, Shepal; Kar, Saibal; Reddy, Vivek; Sievert, Horst; Mullin, Chris; Swarup, Vijay; Whisenant, Brian; Holmes, David

2013-04-30

This study sought to assess quality of life parameters in a subset of patients enrolled in the PROTECT AF (Percutaneous Closure of the Left Atrial Appendage Versus Warfarin Therapy for Prevention of Stroke in Patients With Atrial Fibrillation) trial. The PROTECT AF (Percutaneous Closure of the Left Atrial Appendage Versus Warfarin Therapy for Prevention of Stroke in Patients With Atrial Fibrillation) trial demonstrated that in patients with nonvalvular atrial fibrillation (AF) and CHADS2 (congestive heart failure, hypertension, age, diabetes mellitus, and prior stroke, transient ischemic attack, or thromboembolism) score ≥1, a left atrial appendage closure device is noninferior to long-term warfarin for stroke prevention. Given this equivalency, quality of life (QOL) indicators are an important metric for evaluating these 2 different strategies. QOL using the Short-Form 12 Health Survey, version 2, measurement tool was obtained at baseline and 12 months in a subset of 547 patients in the PROTECT AF trial (361 device and 186 warfarin patients). The analysis cohort consisted of patients for whom either paired quality of life data were available after 12 months of follow-up or for patients who died. With the device, the total physical score improved in 34.9% and was unchanged in 29.9% versus warfarin in whom 24.7% were improved and 31.7% were unchanged (p = 0.01). Mental health improvement occurred in 33.0% of the device group versus 22.6% in the warfarin group (p = 0.06). There was a significant improvement in QOL in patients randomized to device for total physical score, physical function, and in physical role limitation compared to control. There were significant differences in the change in total physical score among warfarin naive and not-warfarin naive subgroups in the device group compared to control, but larger gains were seen with the warfarin naive subgroup with a 12-month change of 1.3 ± 8.8 versus -3.6 ± 6.7 (p = 0.0004) device compared to warfarin. Patients with nonvalvular AF at risk for stroke treated with left atrial appendage closure have favorable QOL changes at 12 months versus patients treated with warfarin. (WATCHMAN Left Atrial Appendage System for Embolic Protection in Patients With Atrial Fibrillation [WATCHMAN PROTECT]; NCT00129545). Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Common Atrial Fibrillation Risk Alleles at 4q25 Predict Recurrence after Catheter-based Atrial Fibrillation Ablation

PubMed Central

Shoemaker, M. Benjamin; Muhammad, Raafia; Parvez, Babar; White, Brenda W.; Streur, Megan; Song, Yanna; Stubblefield, Tanya; Kucera, Gayle; Blair, Marcia; Rytlewski, Jason; Parvathaneni, Sunthosh; Nagarakanti, Rangadham; Saavedra, Pablo; Ellis, Christopher; Whalen, S. Patrick; Roden, Dan M; Darbar, Dawood

2012-01-01

Background Common single nucleotide polymorphisms (SNPs) at chromosome 4q25 (rs2200733, rs10033464) are associated with both lone and typical AF. Risk alleles at 4q25 have recently been shown to predict recurrence of AF after ablation in a population of predominately lone AF, but lone AF represents only 5–30% of AF cases. Objective To test the hypothesis that 4q25 AF risk alleles can predict response to AF ablation in the majority of AF cases. Methods Patients enrolled in the Vanderbilt AF Registry underwent 378 catheter-based AF ablations (median age 60 years, 71% male, 89% typical AF) between 2004 and 2011. The primary endpoint was time to recurrence of any non-sinus atrial tachyarrhythmia (atrial tachycardia, atrial flutter, or AF; [AT/AF]). Results Two-hundred AT/AF recurrences (53%) were observed. In multivariable analysis, the rs2200733 risk allele predicted a 24% shorter recurrence-free time (survival time ratio 0.76 95% confidence interval [CI] 0.6–0.95, P=0.016) compared with wild-type. The heterozygous haplotype demonstrated a 21% shorter recurrence-free time (survival time ratio = 0.79, 95% CI 0.62–0.99) and the homozygous risk allele carriers a 39% shorter recurrence-free time (survival time ratio = 0.61, 95% CI 0.37–1.0) (P=0.037). Conclusion Risk alleles at the 4q25 loci predict impaired clinical response to AF ablation in a population of predominately typical AF patients. Our findings suggest the rs2200733 polymorphism may hold promise as an as an objectively measured patient characteristic that can used as a clinical tool for selection of patients for AF ablation. PMID:23178686

African American race but not genome-wide ancestry is negatively associated with atrial fibrillation among postmenopausal women in the Women's Health Initiative.

PubMed

Perez, Marco V; Hoffmann, Thomas J; Tang, Hua; Thornton, Timothy; Stefanick, Marcia L; Larson, Joseph C; Kooperberg, Charles; Reiner, Alex P; Caan, Bette; Iribarren, Carlos; Risch, Neil

2013-09-01

Atrial fibrillation (AF) is the most common arrhythmia in women and is associated with higher rates of stroke and death. Rates of AF are lower in African American subjects compared with European Americans, suggesting European ancestry could contribute to AF risk. The Women's Health Initiative (WHI) Observational Study (OS) followed up 93,676 women since the mid 1990s for various cardiovascular outcomes including AF. Multivariate Cox hazard regression analysis was used to measure the association between African American race and incident AF. A total of 8,119 African American women from the WHI randomized clinical trials and OS were genotyped on the Affymetrix Human SNP Array 6.0. Genome-wide ancestry and previously reported single nucleotide polymorphisms associated with AF in European cohorts were tested for association with AF using multivariate logistic regression analyses. Self-reported African American race was associated with lower rates of AF (hazard ratio 0.43, 95% CI 0.32-0.60) in the OS, independent of demographic and clinical risk factors. In the genotyped cohort, there were 558 women with AF. By contrast, genome-wide European ancestry was not associated with AF. None of the single nucleotide polymorphisms previously associated with AF in European populations, including rs2200733, were associated with AF in the WHI African American cohort. African American race is significantly and inversely correlated with AF in postmenopausal women. The etiology of this association remains unclear and may be related to unidentified environmental differences. Larger studies are necessary to identify genetic determinants of AF in African Americans. © 2013.

Depression and Physical Inactivity as Confounding the Effect of Obesity on Atrial Fibrillation.

PubMed

Garimella, Roja S; Sears, Samuel F; Gehi, Anil K

2016-06-01

Obesity is associated with an increased likelihood for the development of atrial fibrillation (AF) and with worsened AF symptom severity. However, other factors that are correlated with obesity may confound or mediate the relation of obesity with AF symptom severity. The purpose of this study was to determine if depression and physical inactivity may confound the association of obesity and AF symptom severity. Health status and demographic data were captured by questionnaire for 332 outpatients with documented AF. Weight/height was measured and body mass index (kg/m(2)) calculated. Recent depression symptom severity was assessed using the Patient Health Questionnaire-9 questionnaire. Physical activity during the last month was assessed by questionnaire. AF symptom severity was assessed using the University of Toronto AF Severity scale. Multivariate linear regression was used to evaluate which factors were associated with AF symptom severity. Obesity in patients with AF is associated with increased depression severity. In bivariate analysis, increasing body mass index (p = 0.001), lower levels of physical activity (p <0.001), and more severe depression (p <0.001) were associated with worsened AF symptom severity. In multivariate analysis, only physical activity and depression persisted as significant predictors of AF symptom severity. In conclusion, although obesity likely contributes to the substrate predisposing to the development of AF, other factors may contribute to or mediate the worsened AF symptoms associated with obesity. Depression symptoms and physical inactivity, factors closely correlated with obesity, may exacerbate symptoms in patients with AF. Copyright © 2016 Elsevier Inc. All rights reserved.

Incidence, type of atrial fibrillation and risk factors for stroke: a population-based cohort study

PubMed Central

Johansson, Cecilia; Dahlqvist, Erik; Andersson, Jonas; Jansson, Jan-Håkan; Johansson, Lars

2017-01-01

Purpose The aims of this study were to estimate the incidence of atrial fibrillation and atrial flutter (AF), to assess the presence of provoking factors and risk factors for stroke and systemic embolism, and to determine the type of AF in patients with first-diagnosed AF. Patients and methods This cohort study was performed in northern Sweden between January 1, 2011 and December 31, 2012. Diagnosis registries were searched for the International Classification of Diseases-10 code for AF (I48) to identify cases of incident AF. All AF diagnoses were electrocardiogram-verified. Data pertaining to provoking factors, type of AF and presence of risk factors for stroke and systemic embolism according to the CHA2DS2-VASc score were obtained from medical records. Results The incidence of AF in the entire population was 4.0 per 1,000 person-years. The incidence was 27.5 per 1,000 person-years in patients aged ≥80 years. A total of 21% of all patients had a provoking factor in association with the first-diagnosed episode of AF. The CHA2DS2-VASc score was 2 or higher in 81% of the patients. Permanent AF was the most common type of AF (29%). Conclusion There was a considerable increase in the incidence of AF with age, and a provoking factor was found in one-fifth. The most common type of AF was permanent AF. Four in five patients had a CHA2DS2-VASc score of 2 or more. PMID:28182159

Impaired Left Atrial Strain as a Predictor of New-onset Atrial Fibrillation After Aortic Valve Replacement Independently of Left Atrial Size.

PubMed

Pessoa-Amorim, Guilherme; Mancio, Jennifer; Vouga, Luís; Ribeiro, José; Gama, Vasco; Bettencourt, Nuno; Fontes-Carvalho, Ricardo

2018-06-01

Left atrial dysfunction in aortic stenosis may precede atrial enlargement and predict the occurrence of atrial fibrillation (AF). To test this hypothesis, we assessed left atrial function and determined its impact on the incidence of AF after aortic valve replacement. A total of 149 severe aortic stenosis patients (74±8.6 years, 51% men) with no prior AF were assessed using speckle-tracking echocardiography. Left atrial function was evaluated using peak atrial longitudinal strain (PALS), peak atrial contraction strain (PACS), and phasic left atrial volumes. The occurrence of AF was monitored in 114 patients from surgery until hospital discharge. In multiple linear regression, PALS and PACS were inversely correlated with left atrial dilation, left ventricular hypertrophy, and diastolic function. Atrial fibrillation occurred in 36 patients within a median time of 3 days [interquartile range, 1-4] after aortic valve replacement. In multiple Cox regression, PALS and PACS were independently associated with the incidence of AF (HR, 0.946; 95%CI, 0.910-0.983; P=.005 and HR, 0.932; 95%CI, 0.883-0.984; P=.011, respectively), even after further adjustment for left atrial dimensions. Both reduced PALS and PACS were associated with the incidence of AF in patients with nondilated left atria (P value for the interaction of PALS with left atrial dimensions=.013). In severe aortic stenosis, left atrial dysfunction predicted the incidence of postoperative AF independently of left atrial dilation, suggesting that speckle-tracking echocardiography before surgery may help in risk stratification, particularly in patients with nondilated left atria. Copyright © 2017 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Reduced heart rate response after premature ventricular contraction depending on severity of atrial fibrillation symptoms - Analysis on heart rate turbulence in atrial fibrillation patients.

PubMed

Makimoto, Hisaki; Blockhaus, Christian; Meyer, Christian; Lin, Tina; Jungen, Christiane; Eickholt, Christian; Clasen, Lukas; Schmidt, Jan; Kurt, Muhammed; Müller, Patrick; Shin, Dong-In; Kelm, Malte; Fürnkranz, Alexander

2018-03-01

The severity of symptoms during atrial fibrillation (AF) may be influenced by heart rate and blood pressure variation, due to irregular beats and the related adaptations in baroreflex sensitivity. This study investigated whether heart rate turbulence (HRT) as a reflection of baroreflex sensitivity is related to symptom severity during AF. Ninety-seven patients (pts) who underwent electrophysiological study were enrolled. Consecutive 56 pts had paroxysmal AF (21 with milder symptoms [EHRA I or II; Group-M], 35 with severe symptoms [EHRA III or IV; Group-S]), and 41 age-matched controls without AF were included. After delivering a single ventricular extrastimulus during sinus rhythm and repeating the process 10 times, the quantification of HRT was performed by measuring turbulence onset (TO: heart rate acceleration) and turbulence slope (TS: rate of heart rate deceleration). Group-M pts showed significantly diminished TO as compared to controls and Group-S pts (P = 0.012). There was no significant difference of the TS between the 3 groups. Given that a TO ≥ 0% or TS ≤ 2.5 ms/RR was considered abnormal, Group-M pts showed significantly higher incidences of abnormal HRT as compared to controls and Group-S pts (71% vs 40% vs 21%, respectively, P = 0.0012). Regression analysis demonstrated an independent and significant association between a diminished TO and milder AF symptoms (P < 0.05). The usual heart rate acceleration after premature ventricular contraction is significantly diminished in pts with milder AF symptoms as compared to pts with severe AF symptoms. The mechanism of association between this diminished response and symptoms should be further investigated.

Symptomatic atrial fibrillation and risk of cardiovascular events: data from the Euro Heart Survey.

PubMed

Guerra, Federico; Brambatti, Michela; Nieuwlaat, Robby; Marcucci, Maura; Dudink, Elton; Crijns, Harry J G M; Matassini, Maria Vittoria; Capucci, Alessandro

2017-12-01

Atrial fibrillation (AF) is associated with a wide range of clinical presentations. Whether and how AF symptoms can affect prognosis is still unclear. Aims of the present analysis were to investigate potential predictors of symptomatic AF and to determine if symptoms are associated with higher incidence of cardiovascular (CV) events at 1-year follow-up. The Euro Heart Survey on Atrial Fibrillation included 3607 consecutive patients with documented AF and available follow-up regarding symptoms status. Patients found symptomatic at baseline were classified into still symptomatic (SS group; n = 896) and asymptomatic (SA; n = 1556) at 1 year. Similarly, asymptomatic patients at baseline were classified into still asymptomatic (AA group; n = 903) and symptomatic (AS group; n = 252) at 1 year. Demographics, as well as clinical variables and medical treatments, were tested as potential predictors of symptoms persistence/development at 1-year. We also compared CV events between SS and SA groups, and AS and AA groups at 1-year follow-up. Both persistence and development of AF symptoms were associated with an increased risk of CV hospitalization, stroke, heart failure worsening, and thrombo-embolism. AF type, hypothyroidism, chronic heart failure, and chronic obstructive pulmonary disease (COPD), were independently associated with an increased risk of symptomatic status at 1-year follow-up between SS and SA groups. Persistence or development of symptoms after medical treatment are associated with an increased risk of CV events during a 1-year follow-up. Type of AF, along with hypothyroidism, COPD and chronic heart failure are significantly associated with symptoms persistence despite medical treatment. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2017. For Permissions, please email: journals.permissions@oup.com.

Effects of RAAS Blockers on Atrial Fibrillation Prophylaxis: An Updated Systematic Review and Meta-Analysis of Randomized Controlled Trials.

PubMed

Chaugai, Sandip; Meng, Wen Yeng; Ali Sepehry, Amir

2016-07-01

Impact of atrial fibrillation on clinical outcomes is well recognized, and application of renin-angiotensin-aldosterone system (RAAS) blockers for the prevention of atrial fibrillation (AF) is a theoretically appealing concept. However, clinical trials have yielded inconsistent results. A pooled study of 26 randomized controlled trials (RCTs) assessing the efficacy of RAAS blockers on AF prophylaxis was performed. A total of 28 reports from 26 randomized controlled trials enrolled 165 387 patients, with an overall 24% reduction in the incidence of AF (odds ratio [OR]: 0.76, 95% confidence interval [CI]: 0.68-0.85], P = .000). Forty-nine percent reduction in the incidence of AF (OR: 0.51, 95% CI: 0.30-0.85, P = .010) in systolic heart failure was observed, whereas no significant effect was observed in patients with diastolic heart failure, postmyocardial infarction, and high cardiovascular disease risk. There was a 19% (OR: 0.81, 95% CI: 0.67-1.00, P = .037) reduction in new-onset and 54% (OR: 0.46, 95% CI: 0.33-0.62, P = .000) reduction in recurrent AF in hypertensive patients with 39% (OR: 0.61, 95% CI: 0.44-0.84, P = .003) risk reduction against calcium blockers and 41% (OR: 0.59, 95% CI: 0.44-0.80, P = .001) risk reduction against β blockers. Angiotensin-receptor blocker appeared marginally superior to angiotensin-converting enzyme inhibitor in primary and secondary prevention. This study suggests that RAAS blockade effectively suppresses AF in systolic heart failure, and hypertensives derive greater benefit against new-onset and recurrent AF compared to β blockers, calcium channel blockers, and diuretics. © The Author(s) 2016.

The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) : Exploring the changes in anticoagulant practice in patients with non-valvular atrial fibrillation in the Netherlands.

PubMed

Ten Cate, V; Ten Cate, H; Verheugt, F W A

2016-10-01

There are over 385,000 cases of atrial fibrillation (AF) in the Netherlands, with over 45,000 new cases each year. Among other things, AF patients are at high risk of stroke. Patients are often prescribed oral anticoagulation, such as vitamin K antagonists (VKA), to mitigate these risks. A recently introduced class of oral anticoagulants, non-vitamin K antagonists (NOAC), is quickly gaining currency in global clinical practice. This study provides insight into the changes these new drugs will bring about in Dutch clinical practice.GARFIELD-AF is a large-scale observational AF patient registry initiated in 2009 to track the evolution of global anticoagulation practice, and to study the impact of NOAC therapy in AF in particular. The registry includes a wide array of baseline characteristics and has a particular focus on: (1) bleeding and thromboembolic events; (2) international normalised ratio fluctuations; and (3) therapy compliance and persistence patterns. The results in this paper provide the baseline characteristics of the first cohorts of Dutch participants in this registry and discuss some of the consequences of the changes in anticoagulation practice.Although VKA therapy remains overwhelmingly favoured by Dutch practitioners, NOACs are clearly gaining in popularity. Between 2011 and 2014, NOACs constituted an increasingly large proportion of prescriptions for oral anticoagulants.The insights provided by the GARFIELD-AF registry can be used by healthcare systems to inform better budgetary strategies, by practitioners to better tailor treatment pathways to patients, and finally to promote awareness of the various available treatment options and their associated risks and benefits for patients.

Second harmonic generation imaging of the collagen in myocardium for atrial fibrillation diagnosis

NASA Astrophysics Data System (ADS)

Tsai, Ming-Rung; Chiou, Yu-We; Sun, Chi-Kuang

2009-02-01

Myocardial fibrosis, a common sequela of cardiac hypertrophy, has been shown to be associated with arrhythmias in experimental models. Some research has indicated that myocardial fibrosis plays an important role in predisposing patients to atrial fibrillation. Second harmonic generation (SHG) is an optically nonlinear coherent process to image the collagen network. In this presentation, we observe the SHG images of the collagen matrix in atrial myocardium and we analyzed of collagen fibers arrangement by using Fourier-transform analysis. Moreover, comparing the SHG images of the collagen fibers in atrial myocardium between normal sinus rhythm (NSR) and atrial fibrillation (AF), our result indicated that it is possible to realize the relation between myocardial fibrosis and AF.

Digoxin use in patients with atrial fibrillation and adverse cardiovascular outcomes: a retrospective analysis of the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF).

PubMed

Washam, Jeffrey B; Stevens, Susanna R; Lokhnygina, Yuliya; Halperin, Jonathan L; Breithardt, Günter; Singer, Daniel E; Mahaffey, Kenneth W; Hankey, Graeme J; Berkowitz, Scott D; Nessel, Christopher C; Fox, Keith A A; Califf, Robert M; Piccini, Jonathan P; Patel, Manesh R

2015-06-13

Digoxin is a widely used drug for ventricular rate control in patients with atrial fibrillation (AF), despite a scarcity of randomised trial data. We studied the use and outcomes of digoxin in patients in the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF). For this retrospective analysis, we included and classified patients from ROCKET AF on the basis of digoxin use at baseline and during the study. Patients in ROCKET AF were recruited from 45 countries and had AF and risk factors putting them at moderate-to-high risk of stroke, with or without heart failure. We used Cox proportional hazards regression models adjusted for baseline characteristics and drugs to investigate the association of digoxin with all-cause mortality, vascular death, and sudden death. ROCKET AF was registered with ClinicalTrials.gov, number NCT00403767. In 14,171 randomly assigned patients, digoxin was used at baseline in 5239 (37%). Patients given digoxin were more likely to be female (42% vs 38%) and have a history of heart failure (73% vs 56%), diabetes (43% vs 38%), and persistent AF (88% vs 77%; p<0·0001 for each comparison). After adjustment, digoxin was associated with increased all-cause mortality (5·41 vs 4·30 events per 100 patients-years; hazard ratio 1·17; 95% CI 1·04-1·32; p=0·0093), vascular death (3·55 vs 2·69 per 100 patient-years; 1·19; 1·03-1·39, p=0·0201), and sudden death (1·68 vs 1·12 events per 100 patient-years; 1·36; 1·08-1·70, p=0·0076). Digoxin treatment was associated with a significant increase in all-cause mortality, vascular death, and sudden death in patients with AF. This association was independent of other measured prognostic factors, and although residual confounding could account for these results, these data show the possibility of digoxin having these effects. A randomised trial of digoxin in treatment of AF patients with and without heart failure is needed. Janssen Research & Development and Bayer HealthCare AG. Copyright © 2015 Elsevier Ltd. All rights reserved.

Challenges of stroke prevention in patients with atrial fibrillation in clinical practice.

PubMed

Hobbs, F D Richard; Leach, I

2011-09-01

Strokes and transient ischaemic attacks in patients with atrial fibrillation (AF) can be largely prevented. Risk stratification and appropriate prophylactic regimens help to alleviate the burden of AF-related thromboembolism. Guidelines recommend routine anticoagulation with oral vitamin K antagonists (VKAs) for patients at moderate-to-high risk of stroke, and acetylsalicylic acid (ASA) for those at low risk of stroke. ASA is less effective at reducing the risk of stroke than VKAs; however, ASA does not require monitoring or dose adjustment. Trials of anticoagulants show consistent benefits of oral VKAs for primary and secondary stroke prevention in patients with AF. Nevertheless, VKAs do require frequent coagulation monitoring and dose adjustment because of their variable dose-response profile, narrow therapeutic window, increased risk for bleeding complications and numerous food and drug interactions. This review aims to provide an overview of the clinical challenges of anticoagulant therapy for the prevention of stroke in patients with AF.

[Right atrial appendage thrombosis during atrial fibrillation: an element to look for].

PubMed

Barbati, Giovanni; De Domenico, Renato; Rossi, Stefania; Vecchiato, Elena; Zeppellini, Roberto

2017-03-01

Oral anticoagulant therapy (OAT) is a mainstay of atrial fibrillation (AF) pharmacological treatment. Left atrial appendage closure is a possible treatment, when feasible, in patients with intracerebral hemorrhage during OAT. We report a case of right atrial appendage thrombosis in a patient with chronic AF admitted for syncope due to diuretic-induced orthostatic hypotension. Two years previously, he had undergone left atrial appendage closure with the Amplatzer Cardiac Plug device because of intracerebral hemorrhage during OAT. After neurological consult, OAT was resumed with apixaban 5 mg twice daily, and transesophageal echocardiography performed two months later showed complete resolution of the right atrial appendage thrombosis. This particular case underlines the importance of searching for a possible right atrial appendage thrombosis in patients affected by AF, and suggests that left atrial appendage closure in AF patients not suitable for OAT does not fully eliminate the risk of thromboembolism.

Surgical perspectives in the management of atrial fibrillation

PubMed Central

Kyprianou, Katerina; Pericleous, Agamemnon; Stavrou, Antonio; Dimitrakaki, Inetzi A; Challoumas, Dimitrios; Dimitrakakis, Georgios

2016-01-01

Atrial fibrillation (AF) is the most common cardiac arrhythmia and a huge public health burden associated with significant morbidity and mortality. For decades an increasing number of patients have undergone surgical treatment of AF, mainly during concomitant cardiac surgery. This has sparked a drive for conducting further studies and researching this field. With the cornerstone Cox-Maze III “cut and sew” procedure being technically challenging, the focus in current literature has turned towards less invasive techniques. The introduction of ablative devices has revolutionised the surgical management of AF, moving away from the traditional surgical lesions. The hybrid procedure, a combination of catheter and surgical ablation is another promising new technique aiming to improve outcomes. Despite the increasing number of studies looking at various aspects of the surgical management of AF, the literature would benefit from more uniformly conducted randomised control trials. PMID:26839656

Profile of atrial fibrillation inpatients: Cardiovascular risk factors and cardiac rehabilitation programme delivery and referral patterns.

PubMed

Gallagher, Robyn; Zhang, Ling; Roach, Kellie; Sadler, Leonie; Belshaw, Julie; Kirkness, Ann; Proctor, Ross; Neubeck, Lis

2015-12-01

Atrial fibrillation (AF) is increasingly common; however, the cardiovascular risk factor profile and the patterns of delivery and referral to cardiac rehabilitation (CR) in this population are poorly described. We conducted an audit of medical records (n = 145) of patients admitted with AF in one local health district in Sydney, Australia. Patients were aged a mean 72 years, and 51% were male. Lack of risk factor documentation was common. Despite this, 65% had two or more modifiable cardiovascular risk factors, including hypertension (63%) and hypercholesterolaemia (52%). Referral to Phase II CR occurred for 25% and was decreased with permanent AF diagnosis and increased with more risk factors. AF patients admitted to hospital have multiple cardiovascular risk factors but limited risk factor screening and/or referral to outpatient CR programmes. © 2014 Wiley Publishing Asia Pty Ltd.

Atrial fibrillation and silent stroke: links, risks, and challenges.

PubMed

Hahne, Kathrin; Mönnig, Gerold; Samol, Alexander

2016-01-01

Atrial fibrillation (AF) is the most common cardiac arrhythmia, with a projected number of 1 million affected subjects in Germany. Changes in age structure of the Western population allow for the assumption that the number of concerned people is going to be doubled, maybe tripled, by the year 2050. Large epidemiological investigations showed that AF leads to a significant increase in mortality and morbidity. Approximately one-third of all strokes are caused by AF and, due to thromboembolic cause, these strokes are often more severe than those caused by other etiologies. Silent brain infarction is defined as the presence of cerebral infarction in the absence of corresponding clinical symptomatology. Progress in imaging technology simplifies diagnostic procedures of these lesions and leads to a large amount of diagnosed lesions, but there is still no final conclusion about frequency, risk factors, and clinical relevance of these infarctions. The prevalence of silent strokes in patients with AF is higher compared to patients without AF, and several studies reported high incidence rates of silent strokes after AF ablation procedures. While treatment strategies to prevent clinically apparent strokes in patients with AF are well investigated, the role of anticoagulatory treatment for prevention of silent infarctions is unclear. This paper summarizes developments in diagnosis of silent brain infarction and its context to AF.

The burden of proof: The current state of atrial fibrillation prevention and treatment trials

PubMed Central

Zakeri, Rosita; Van Wagoner, David R.; Calkins, Hugh; Wong, Tom; Ross, Heather M.; Heist, E. Kevin; Meyer, Timothy E.; Kowey, Peter R.; Mentz, Robert J.; Cleland, John G.; Pitt, Bertram; Zannad, Faiez; Linde, Cecilia

2017-01-01

Atrial fibrillation (AF) is an age-related arrhythmia of enormous socioeconomic significance. In recent years, our understanding of the basic mechanisms that initiate and perpetuate AF has evolved rapidly, catheter ablation of AF has progressed from concept to reality, and recent studies suggest lifestyle modification may help prevent AF recurrence. Emerging developments in genetics, imaging, and informatics also present new opportunities for personalized care. However, considerable challenges remain. These include a paucity of studies examining AF prevention, modest efficacy of existing antiarrhythmic therapies, diverse ablation technologies and practice, and limited evidence to guide management of high-risk patients with multiple comorbidities. Studies examining the long-term effects of AF catheter ablation on morbidity and mortality outcomes are not yet completed. In many ways, further progress in the field is heavily contingent on the feasibility, capacity, and efficiency of clinical trials to incorporate the rapidly evolving knowledge base and to provide substantive evidence for novel AF therapeutic strategies. This review outlines the current state of AF prevention and treatment trials, including the foreseeable challenges, as discussed by a unique forum of clinical trialists, scientists, and regulatory representatives in a session endorsed by the Heart Rhythm Society at the 12th Global CardioVascular Clinical Trialists Forum in Washington, DC, December 3–5, 2015. PMID:28161513

Atrial fibrillation ablation using cryoballoon technology: Recent advances and practical techniques.

PubMed

Chen, Shaojie; Schmidt, Boris; Bordignon, Stefano; Bologna, Fabrizio; Perrotta, Laura; Nagase, Takahiko; Chun, K R Julian

2018-04-16

Atrial fibrillation (AF) affects 1-2% of the population, and its prevalence is estimated to double in the next 50 years as the population ages. AF results in impaired patients' life quality, deteriorated cardiac function, and even increased mortality. Antiarrhythmic drugs frequently fail to restore sinus rhythm. Catheter ablation is a valuable treatment approach for AF, even as a first-line therapy strategy in selected patients. Effective electrical pulmonary vein isolation (PVI) is the cornerstone of all AF ablation strategies. Use of radiofrequency (RF) catheter in combination of a three-dimensional electroanatomical mapping system is the most established ablation approach. However, catheter ablation of AF is challenging even sometimes for experienced operators. To facilitate catheter ablation of AF without compromising the durability of the pulmonary vein isolation, "single shot" ablation devices have been developed; of them, cryoballoon ablation, is by far the most widely investigated. In this report, we review the current knowledge of AF and discuss the recent evidence in catheter ablation of AF, particularly cryoballoon ablation. Moreover, we review relevant data from the literature as well as our own experience and summarize the key procedural practical techniques in PVI using cryoballoon technology, aiming to shorten the learning curve of the ablation technique and to contribute further to reduction of the disease burden. © 2018 Wiley Periodicals, Inc.

Comparison of C-reactive protein levels in patients who do and do not develop atrial fibrillation during electrophysiologic study.

PubMed

Pirat, Bahar; Atar, Ilyas; Ertan, Cagatay; Bozbas, Huseyin; Gulmez, Oyku; Müderrisoglu, Haldun; Ozin, Bulent

2007-11-15

C-reactive protein (CRP) was increased in patients with atrial fibrillation (AF). The aim of this study was to evaluate CRP after inducing AF in 39 patients undergoing electrophysiologic study (EPS). After a diagnostic EPS, programmed atrial stimulation with 3 extra stimuli from the right atrium was performed in all patients. CRP was measured before and 6 and 24 hours after the procedure. Patients in whom AF was induced were monitored for 24 hours. AF was induced in 18 of 39 patients. Twenty-one patients without a tachyarrhythmia constituted the control group. Groups were similar with regard to age, gender, incidences of hypertension and diabetes, and history of coronary artery disease. On average, AF lasted 4.8 hours, and spontaneous conversion to sinus rhythm was observed in all patients. There were no statistically significant differences with respect to baseline and 6-hour CRP values between groups. However, mean CRP at 24 hours was significantly higher in patients with AF compared with controls (10 +/- 11 and 3.9 +/- 4.2 mg/L; p = 0.04). In conclusion, induction of AF during EPS led to increased CRP. This finding suggested that increased CRP may be the consequence of AF.

South Asian ethnicity is associated with a lower prevalence of atrial fibrillation despite greater prevalence of established risk factors: a population-based study in Bradford Metropolitan District.

PubMed

Gillott, Richard Geoffrey; Willan, Kathryn; Kain, Kirti; Sivananthan, Uduvil Mohanaraj; Tayebjee, Muzahir Hassan

2017-03-01

Previous studies indicate that South Asians (SAs) may have a reduced risk of developing atrial fibrillation (AF) despite having a higher prevalence of traditional cardiovascular risk factors. This observational study was designed to explore the relative differences between SAs and Whites in a well-defined, multi-ethnic population with careful consideration of traditional cardiovascular risk factors that are thought to contribute to the development of AF. Anonymized data from 417 575 adults were sourced from primary care records within Bradford Metropolitan District, UK. Atrial fibrillation diagnosis was indicated by the presence on the AF Quality Outcomes Framework register. Self-reported ethnicity was mapped to census ethnic codes. The age-standardized prevalence rates of AF were calculated for comparison between the White and SA populations; our study sample presented relative proportions of 2.39 and 0.4%. Multivariable logistic regression analysis was performed to estimate the odds of developing AF given SA ethnicity. Adjustment for age, sex, and established risk factors found a 71% reduction in odds of AF in SAs when compared with Whites [odds ratio (OR): 0.29, 95% confidence interval (CI): 0.26-0.32]. When stratified by ethnicity, analyses revealed significantly different odds of AF for patients with diabetes; diabetes was not associated with the development of AF in the SA population (0.81, 95% CI: 0.63-1.05). This study, in a multi-ethnic population, presents ethnicity as a predictor of AF in which prevalence is significantly lower in SAs when compared with Whites. This is despite SAs having a higher frequency of established risk factors for the development of AF, such as ischaemic heart disease, heart failure, hypertension, and type 2 diabetes. These findings are consistent with previous literature and add weight to the need for further investigation, although this is the first study to investigate the differential associations of individual risk factors with development of AF. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

Mechanistic Comparison of "Nearly Missed" Versus "On-Target" Rotor Ablation.

PubMed

Yamazaki, Masatoshi; Avula, Uma Mahesh R; Berenfeld, Omer; Kalifa, Jérôme

2015-08-01

This study used advanced optical mapping techniques to examine atrial fibrillation (AF) dynamics before and after 2 distinct electrogram-based ablation strategies: complex fractionated atrial electrograms (CFAEs) and DFmax/rotor ablation. Among the electrogram analytical features proposed to unravel the atrial regions that perpetuate AF, CFAEs, highest dominant frequency sites (DFmax), and, more recently, phase analysis-enabled rotor mapping have received the largest attention. Still, the mechanisms by which these approaches modulate AF dynamics and lead to AF termination are unknown. In Langendorff-perfused sheep hearts, AF was maintained by the continuous perfusion of acetylcholine and high-resolution endocardial-epicardial optical videos were recorded from the left atrial free wall and the posterior left atrium. Then, DFmax/rotor regions (n = 7), or CFAE regions harboring the highest wavebreak density (HWD) (n = 5), were targeted with a 4F ablation catheter (5 to 15 W, 30 to 60 s/point). Thereafter, we examined the changes in AF dynamics and whether AF terminated. DFmax/rotor point ablation resulted in a significant decrease in DFmax values. In 2 animals AF terminated, whereas in the remaining 5 animals the post-ablation DFmax domain remained in the vicinity of its pre-ablation location. However, after HWD/CFAEs density ablation, DFmax values did not change, AF did not terminate, and post-ablation DFmax domains relocated from the left atrial free wall to the pulmonary vein-posterior left atrium region. In another group of hearts (n = 12), we observed that upon a progressive increase in acetylcholine concentration-mimicking the acute electrophysiological changes occurring after ablation-3-dimensional rotors drifted from one atrial region to another along large gradients of myocardial thickness. "On-target" DFmax/rotor ablation leads to the annihilation of the fibrillation-driving rotor. This translates into large decreases in AF frequency or AF termination. In contrast, "nearly missed" HWD/CFAEs ablation spares the fibrillation-driving rotor, and set the stage for rotor drift along large myocardial thickness gradients. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Admissions with atrial fibrillation in a multiracial population in Kuala Lumpur, Malaysia.

PubMed

Freestone, B; Rajaratnam, R; Hussain, N; Lip, G Y H

2003-10-01

There are established differences in cardiovascular disease in different racial groups. Worldwide, the literature regarding the clinical epidemiology of atrial fibrillation in non-white populations is scarce. To document the prevalence of atrial fibrillation (AF) in the multiracial population of Malaysia, and to describe the clinical features and management of these patients. Busy city centre general hospital in Kuala Lumpur, Malaysia, over a 1-month period. One-thousand four hundred and thirty-five acute medical admissions, of whom 40 patients (2.8%) had AF. Of 1435 acute medical admissions to Kuala Lumpur General Hospital over the 4-week study period, 40 had AF (21 male, 19 female; mean age 65 years). Of these, 18 were Malay, 16 Chinese and six Indian. Nineteen patients had previously known AF (seven with paroxysmal AF) and 21 were newly diagnosed cases. The principal associated medical conditions were ischaemic heart disease (42.5%), hypertension (40%) and heart failure (40%). Dyspnoea was the commonest presentation, whilst stroke was the cause of presentation in only two patients. Investigations were under-utilised, with chest X-ray and echocardiography in only 62.5% of patients and thyroid function checked in 15%. Only 16% of those with previously diagnosed AF were on warfarin, with a further three on aspirin. Anticoagulant therapy was started in 13.5% of patients previously not on warfarin, and aspirin in 8%. Records of contraindications to warfarin were unreliable, being identified in only 25%. For those with known AF, 58% were on digoxin. For new onset AF, digoxin was again the most common rate-limiting treatment, initiated in 38%, whilst five patients with new onset AF were commenced on amiodarone. DC cardioversion was not used in any of the patients with new onset AF. Amongst acute medical admissions to a single centre in Malaysia the prevalence of AF was 2.8%. Consistent with previous similar surveys in mainly western (caucasian) populations, standard investigations in this Malaysian cohort were also inadequate and there was underuse of anticoagulation, medication for ventricular rate control and cardioversion to sinus rhythm.

Endurance Sport Activity and Risk of Atrial Fibrillation – Epidemiology, Proposed Mechanisms and Management

PubMed Central

Vicedomini, Gabriele; Pappone, Carlo

2014-01-01

There is evidence for a higher prevalence of atrial fibrillation (AF) in athletes engaged in long-term endurance sports training compared with the general population. Although atrial anatomic adaptations, alterations in autonomic nervous system, chronic systemic inflammation and fibrosis have been proposed as potential mechanisms, they remain speculative. Medical therapy with long-term antiarrhythmic agents or ‘pill in the pocket’ medications is hampered by limitations, such as sports eligibility and interference with exercise tolerance. AF ablation represents a valid therapeutic option with results similar to these achieved in other patients. Nevertheless, further clinical trials are needed to confirm whether endurance sport practice affects the maintenance of sinus rhythm following catheter ablation of AF. PMID:26835059

Implantable defibrillators configured for hybrid therapy of persistent and permanent atrial fibrillation: initial clinical experience with a novel lead system.

PubMed

Rao, Hygriv B; Saksena, Sanjeev

2005-08-01

Hybrid therapy strategies have combined antiarrhythmic drugs (AAD) with pacemakers, atrio-ventricular defibrillators (AV ICD) or atrial ablation individually. The feasibility combining AAD with dual site RA pacing (DAP) in an AV ICD has not been examined. We used an AV ICD with a novel lead configuration permitting DAP, antitachycardia pacing (ATP) or atrial shocks (ADF) in patients (pts) with refractory persistent or permanent AF. Hybrid therapy included linear RA ablation and/or focal ablation. Continuous DAP and automatic ATP with patient or physician activated ADF. 24 pts, mean age 66 +/- 10 yrs, with cardiac disease (22 pts), underwent insertion of an AVICD with dual RA leads. 20 patients had concomitant ablative procedures (RA only = 19, RA + LA = 1) and all pts continued previously ineffective AAD. During a follow-up of 2-36 months (mean 17 +/- 8 mos), rhythm control was restored in all pts & maintained long-term in 19 (83%) pts. 8 pts used AF termination therapies successfully. Device datalogs showed no episodes of AF in 6 pts, asymptomatic brief arrhythmias in 4 pts, infrequent paroxysmal AF in 9 pts & persistent AF recurred in 5 pts. AV ICD detection algorithms reliably detected AF or AT in the DAP mode in all pts. Intermittent brief P wave double counting occurred during AT in selected pts. No pt received inappropriate ADF therapy. 1. DAP can be safely incorporated in an AVICD devices for use in an hybrid therapy strategy for AF pts. 2. These devices can be effective for both AF prevention & termination. 3. Long term rhythm control can be achieved and documented by device datalogs in persistent and permanent AF.

Association of Left Atrial Function Index With Late Atrial Fibrillation Recurrence after Catheter Ablation.

PubMed

Sardana, Mayank; Ogunsua, Adedotun A; Spring, Matthew; Shaikh, Amir; Asamoah, Owusu; Stokken, Glenn; Browning, Clifford; Ennis, Cynthia; Donahue, J Kevin; Rosenthal, Lawrence S; Floyd, Kevin C; Aurigemma, Gerard P; Parikh, Nisha I; McManus, David D

2016-12-01

Although catheter ablation (CA) for atrial fibrillation (AF) is commonly used to improve symptoms, AF recurrence is common and new tools are needed to better inform patient selection for CA. Left atrial function index (LAFI), an echocardiographic measure of atrial mechanical function, has shown promise as a noninvasive predictor of AF. We hypothesized that LAFI would relate to AF recurrence after CA. All AF patients undergoing index CA were enrolled in a prospective institutional AF Treatment Registry between 2011 and 2014. LAFI was measured post hoc from pre-ablation clinical echocardiographic images in 168 participants. Participants were mostly male (33% female), middle-aged (60 ± 10 years), obese and had paroxysmal AF (64%). Mean LAFI was 25.9 ± 17.6. Over 12 months of follow-up, 78 participants (46%) experienced a late AF recurrence. In logistic regression analyses adjusting for factors known to be associated with AF, lower LAFI remained associated with AF recurrence after CA [OR 0.04 (0.01-0.67), P = 0.02]. LAFI discriminated AF recurrence after CA slightly better than CHADS2 (C-statistic 0.60 LAFI, 0.57 CHADS2). For participants with persistent AF, LAFI performed significantly better than CHADS2 score (C statistic = 0.79 LAFI, 0.56 CHADS2, P = 0.02). LAFI, an echocardiographic measure of atrial function, is associated with AF recurrence after CA and has improved ability to discriminate AF recurrence as compared to the CHADS-2 score, especially among persistent AF patients. Since LAFI can be calculated using standard 2D echocardiographic images, it may be a helpful tool for predicting AF recurrence. © 2016 Wiley Periodicals, Inc.

Clinical, Electrocardiographic, and Echocardiographic Parameter Combination Predicts the Onset of Atrial Fibrillation.

PubMed

Soeki, Takeshi; Matsuura, Tomomi; Tobiume, Takeshi; Bando, Sachiko; Matsumoto, Kazuhisa; Nagano, Hiromi; Uematsu, Etsuko; Kusunose, Kenya; Ise, Takayuki; Yamaguchi, Koji; Yagi, Shusuke; Fukuda, Daiju; Yamada, Hirotsugu; Wakatsuki, Tetsuzo; Shimabukuro, Michio; Sata, Masataka

2018-05-30

The ability to identify risk markers for new-onset atrial fibrillation (AF) is critical to the development of preventive strategies, but it remains unknown whether a combination of clinical, electrocardiographic, and echocardiographic parameters predicts the onset of AF. In the present study, we evaluated the predictive value of a combined score that includes these parameters.Methods and Results:We retrospectively studied 1,040 patients without AF who underwent both echocardiography and 24-h Holter electrocardiography between May 2005 and December 2010. During a median follow-up period of 68.4 months (IQR, 49.9-93.3 months), we investigated the incidence of new-onset AF. Of the 1,040 patients, 103 (9.9%) developed AF. Patients who developed AF were older than patients who did not. Total heart beats, premature atrial contraction (PAC) count, maximum RR interval, and frequency of sinus pause quantified on 24-h electrocardiography were associated with new-onset AF. LA diameter (LAD) on echocardiography was also associated with the development of AF. On multivariate Cox analysis, age ≥58 years, PAC count ≥80 beats/day, maximum RR interval ≥1.64 s, and LAD ≥4.5 cm were independently associated with the development of AF. The incidence rate of new-onset AF significantly increased as the combined score (i.e., the sum of the risk score determined using hazard ratios) increased. A combined score that includes age, PAC count, maximum RR interval, and LAD could help characterize the risk of new-onset AF.

Statin and Atrial Fibrilation: When does it work?

PubMed

Fauchier, Laurent; Clementy, Nicolas; Pierre, Bertrand; Babuty, Dominique

2012-01-01

In the recent years, some clinical and experimental studies have suggested that the use of statins may protect against atrial fibrillation (AF). A relation between inflammation and the development of AF has been described, and the potent anti-inflammatory and antioxidant properties of statins may make them effective in preventing the development of AF. A global analysis of the literature suggests that the use of statins is associated with a decreased risk of incidence or recurrence of AF in some cases. However, this beneficial effect is not seen for all types of AF in all the patients. The use of statins seems associated 1) with a lack of benefit in primary prevention of AF, 2) with a significant but heterogeneous decreased risk of recurrence of AF in secondary prevention, and 3) with a very significant and homogeneous reduction for the risk of post operative AF. An intensive lipid lowering statin regimen does not provide greater protection against AF. Patients with coronary heart disease are curr ently treated with statins in most cases, and this may not have an impact on their treatment. In contrast, it remains to determine more accurately if statins may bring a significant benefit for some AF patients without any type of established atherosclerotic disease or with a low risk of atherogenesis. Since it remains uncertain whether the suppression of AF in these patients is beyond doubt beneficial, prescribing statins for this purpose alone should not be recommended at the present time.

Short-Term Heparin Kinetics during Catheter Ablation of Atrial Fibrillation.

PubMed

Gabus, Vincent; Rollin, Anne; Maury, Philippe; Forclaz, Andrei; Pascale, Patrizio; Dhutia, Harshil; Bisch, Laurence; Pruvot, Etienne

2015-10-01

Percutaneous catheter ablation of atrial fibrillation (CA-AF) is a treatment option for symptomatic drug-refractory atrial fibrillation (AF). CA-AF carries a risk for thromboembolic complications that has been minimized by the use of intraprocedural intravenous unfractionated heparin (UFH). The optimal administration of UFH as well as its kinetics are not well established and need to be precisely determined. A total 102 of consecutive patients suffering from symptomatic drug-refractory AF underwent CA-AF. The mean age was 61 ± 10 years old. After transseptal puncture of the fossa ovalis, weight-adjusted UFH bolus (100 U/kg) was infused. A significant increase in activated clotting time (ACT) was observed from an average value of 100 ± 27 seconds at baseline, to 355 ± 94 seconds at 10 min (T10), to 375 ± 90 seconds at 20 min (T20). Twenty-four patients failed to reach the targeted ACT value of ≥300 seconds at T10 and more than half of these remained with subtherapeutic ACT values at T20. This subset of patients showed similar clinical characteristics and amount of UFH but were more frequently prescribed preprocedural vitamin K1 than the rest of the study population. In a typical intervention setting, UFH displays unexpected slow anticoagulation kinetics in a significant proportion of procedures up to 20 minutes after infusion. These findings support the infusion of UFH before transseptal puncture or any left-sided catheterization with early ACT measurements to identify patients with delayed kinetics. They are in line with recent guidelines to perform CA-AF under therapeutic anticoagulation. © 2015 Wiley Periodicals, Inc.

Persistent Atrial Fibrillation Ablation using the Tip-Versatile Ablation Catheter.

PubMed

Davies, Edward J; Clayton, Ben; Lines, Ian; Haywood, Guy A

2016-07-01

The mechanisms by which persistent atrial fibrillation (PsAF) develops are incompletely understood. Consequently, the optimal strategy for the ablative management of PsAF remains debated. Current methods are often time consuming, complex and non-reproducible. We assessed the Tip-Versatile Ablation Catheter (T-VAC) technique, a rapidly delivered, empirical technique based on the box-set concept using duty-cycled linear catheter ablation technology. Forty-four procedures in 40 patients undergoing PsAF ablation with the novel technique were prospectively entered onto a database: 27 de novo. Primary endpoint was freedom from arrhythmia at over two-year follow-up. Secondary endpoints were time to first arrhythmia recurrence, freedom from atrial fibrillation (AF) on and off antiarrhythmic drugs (AAD), procedural and fluoroscopy duration and complication rate. At mean follow-up of 33 months, absolute freedom from arrhythmia recurrence was 45% in the de novo group. Overall, at 33 (IQR 24-63) months, 60% of de novo patients were in sustained normal sinus rhythm and a further 15% reported only occasional paroxysms of AF at long-term follow-up. Procedure time was 192±25 mins, total energy delivered 2239±883s and fluoroscopy time was 60±10mins. In selected patients with persistent AF, a long-term rate of 60% arrhythmia free survival off AAD can be achieved using this novel T-VAC technique. Copyright © 2016 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

Left Atrial Appendage Exclusion for Atrial Fibrillation

PubMed Central

Syed, Faisal F.; DeSimone, Christopher V.; Friedman, Paul A.; Asirvatham, Samuel J.

2015-01-01

SYNOPSIS Percutaneous left atrial appendage (LAA) closure is increasingly being used as a treatment strategy to prevent stroke in patients with atrial fibrillation (AF) who have contraindications to anticoagulants. A number of approaches and devices have been developed in the last few years, each with their own unique set of advantages and disadvantages. We review the published studies on surgical and percutaneous approaches to LAA closure; focusing on stroke mechanisms in AF, LAA structure and function relevant to stroke prevention, practical differences in procedural approach, and clinical considerations surrounding management. PMID:25443240

Clinical presentation, management, and outcomes in the Indian Heart Rhythm Society-Atrial Fibrillation (IHRS-AF) registry.

PubMed

Vora, A; Kapoor, A; Nair, M; Lokhandwala, Y; Narsimhan, C; Ravikishore, A G; Dwivedi, S K; Namboodiri, N; Hygriv, R; Saxena, A; Nabar, A; Garg, S; Bardoloi, N; Yadav, R; Nambiar, A; Pandurangi, U; Jhala, D; Naik, A; Nagmallesh; Rajagopal, S; Selvaraj, R; Arora, V; Thachil, A; Thomas, J; Panicker, G

A national atrial fibrillation (AF) registry was conducted under the aegis of the Indian Heart Rhythm Society (IHRS), to capture epidemiological data-type of AF, clinical presentation and comorbidities, current treatment practices, and 1-year follow-up outcomes. A total of 1537 patients were enrolled from 24 sites in India in the IHRS-AF registry from July 2011 to August 2012. Their baseline characteristics and follow-up data were recorded in case report forms and subsequently analyzed. The average age of Indian AF patients was 54.7 years. There was a marginal female preponderance - 51.5% females and 48.5% males. At baseline, 20.4% had paroxysmal AF; 33% had persistent AF; 35.1% had permanent AF and 11% had first AF episode. At one-year follow-up, 45.6% patients had permanent AF. Rheumatic valvular heart disease (RHD) was present in 47.6% of patients. Hypertension, heart failure, coronary artery disease, and diabetes were seen in 31.4%, 18.7%, 16.2%, and 16.1%, respectively. Rate control was the strategy used in 75.2% patients, digoxin and beta-blockers being the most frequently prescribed rate-control drugs. Oral anticoagulation (OAC) drugs were used in 70% of patients. The annual mortality was 6.5%, hospitalization 8%, and incidence of stroke 1%. In India, AF patients are younger and RHD is still the most frequent etiology. Almost two-third of the patients have persistent/permanent AF. At one-year follow-up, there is a significant mortality and morbidity in AF patients in India. Copyright © 2016. Published by Elsevier B.V.

Successful Repeat Catheter Ablation of Recurrent Longstanding Persistent Atrial Fibrillation With Rotor Elimination as the Procedural Endpoint: A Case Series.

PubMed

Sommer, Philipp; Kircher, Simon; Rolf, Sascha; John, Silke; Arya, Arash; Dinov, Borislav; Richter, Sergio; Bollmann, Andreas; Hindricks, Gerhard

2016-03-01

There remains a lack of consensus regarding the ideal ablation strategy for atrial fibrillation (AF), particularly in patients with persistent or longstanding persistent AF. Given increasing evidence from clinical imaging studies that rotors sustain AF, rotor elimination may be a desirable procedural endpoint. However, there is no description to date of the clinical outcomes using rotor elimination during ablation as the procedural endpoint. Moreover, a series of studies question whether procedural AF termination is a desirable endpoint for ablation after many forms of AF ablation. We report a single-center experience of rotor elimination during AF ablation using Focal Impulse and Rotor Mapping (FIRM), describing 20 consecutive patients with case descriptions of 3 patients with recurrent longstanding persistent AF after prior ablation. In all cases, endocardial mapping using a 64-electrode basket catheter was performed to identify rotors, which were eliminated using radiofrequency catheter ablation. After it was verified that all identified rotors were eliminated, standard ablation consisting of PV isolation was performed. Notably, persistent AF terminated in only 1/20 (5%) patients. However, after a follow-up of 6 months, single-procedure freedom from AF was 80% (16/20 patients) with only 1 patient on antiarrhythmic drugs. All three patients in the highlighted series are AF free despite the lack of acute procedural AF termination. Patients with persistent AF including those with unsuccessful prior ablation can be treated successfully by rotor targeted ablation, using the elimination of all rotors rather than acute AF termination as the procedural endpoint. © 2015 Wiley Periodicals, Inc.

A systematic review of the health benefits of exercise rehabilitation in persons living with atrial fibrillation.

PubMed

Giacomantonio, Nicholas B; Bredin, Shannon S D; Foulds, Heather J A; Warburton, Darren E R

2013-04-01

This systematic review sought to evaluate critically the health benefits of physical activity among persons with atrial fibrillation (AF). AF is increasing in Western society. While health benefits of physical activity are well established, benefits of physical activity among individuals with AF are not clearly identified. Literature was retrieved systematically through searching electronic databases (MEDLINE, EMBASE, Cochrane), cross-referencing, and drawing on the authors' knowledge. Identified original research articles evaluated health benefits of physical activity among persons with AF or effects of physical activity on AF incidence. From 1056 individual citations, 36 eligible articles were identified. Moderate-intensity physical activity was found to improve exercise capacity, quality of life, and the ability to carry out activities of daily living among persons with AF (n = 6). Increased incidence of AF was not associated with physical activity among the general population (n = 2), although long-term vigorous endurance exercise may be associated with increased incidence of AF (n = 7), and greater risks may be associated with high-intensity physical activity among those with AF (n = 2). Moderate-intensity physical activity among individuals with AF does not adversely alter training outcomes, functional capacity, morbidity, or mortality compared with those in sinus rhythm (n = 12). Physical activity may improve management and treatment of AF (n = 6) and, among at-risk populations, may reduce incidence of AF (n = 3). In conclusion, moderate-intensity physical activity should be encouraged among persons with or at risk of AF. Further research is needed. Copyright © 2013 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Atrial Fibrillation: Mechanisms, Therapeutics, and Future Directions

PubMed Central

Pellman, Jason; Sheikh, Farah

2017-01-01

Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia, affecting 1% to 2% of the general population. It is characterized by rapid and disorganized atrial activation leading to impaired atrial function, which can be diagnosed on an EKG by lack of a P-wave and irregular QRS complexes. AF is associated with increased morbidity and mortality and is a risk factor for embolic stroke and worsening heart failure. Current research on AF support and explore the hypothesis that initiation and maintenance of AF require pathophysiological remodeling of the atria, either specifically as in lone AF or secondary to other heart disease as in heart failure-associated AF. Remodeling in AF can be grouped into three categories that include: (i) electrical remodeling, which includes modulation of L-type Ca2+ current, various K+ currents and gap junction function; (ii) structural remodeling, which includes changes in tissues properties, size, and ultrastructure; and (iii) autonomic remodeling, including altered sympathovagal activity and hyperinnervation. Electrical, structural, and autonomic remodeling all contribute to creating an AF-prone substrate which is able to produce AF-associated electrical phenomena including a rapidly firing focus, complex multiple reentrant circuit or rotors. Although various remodeling events occur in AF, current AF therapies focus on ventricular rate and rhythm control strategies using pharmacotherapy and surgical interventions. Recent progress in the field has started to focus on the underlying substrate that drives and maintains AF (termed upstream therapies); however, much work is needed in this area. Here, we review current knowledge of AF mechanisms, therapies, and new areas of investigation. PMID:25880508

Assessment of the clinical efficacy of the heart spectrum blood pressure monitor for diagnosis of atrial fibrillation: An unblinded clinical trial.

PubMed

Kao, Wei-Fong; Hou, Sen-Kuang; Huang, Chun-Yao; Chao, Chun-Chieh; Cheng, Chung-Chih; Chen, Yi-Jung

2018-01-01

Atrial fibrillation (AF) is the most common arrhythmia. The most common diagnostic method, 12-lead electrocardiogram (ECG), can record episodes of arrhythmia from which the type and severity can be determined. The Heart Spectrum Blood Pressure Monitor (P2; OSTAR Meditech Corp., New Taipei City, Taiwan) is used to measure cardiovascular pressure change with fast Fourier transform (FFT) analysis to obtain heart rate frequency variability and accurate blood pressure data. We compared the diagnostic efficacy of the Heart Spectrum Blood Pressure Monitor to a 12-lead ECG (gold standard) for patients with AF. Three measurement methods were used in this study to analyze the heart index and compare the results with simultaneous 12-lead ECG: blood pressure; mean arterial pressure, which was calculated from individual blood pressure as a constant pressure; and a constant pressure of 60 mmHg. The physician used a 12-lead ECG and the Heart Spectrum Blood Pressure Monitor simultaneously. The Heart Spectrum Blood Pressure Monitor used FFT analysis to diagnose AF, and the findings were compared to the 12-lead ECG readings. This unblinded clinical trial was conducted in the emergency department of Taipei Medical University Hospital. Twenty-nine subjects with AF and 33 without AF aged 25 to 97 y (mean, 63.5 y) were included. Subjects who were exposed to high-frequency surgical equipment during testing, those with cardiac pacemakers or implantable defibrillators, and pregnant women were excluded. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 97%, 97%, 97%, and 97%, respectively, for method 1; 90%, 100%, 100%, and 91%, respectively, for method 2; and 100%, 94%, 94%, and 100%, respectively, for method 3. The sensitivity, specificity, PPV, and NPV for both methods ranged between 90% and 100%, indicating that the Heart Spectrum Blood Pressure Monitor can be effectively applied for AF detection.

Assessment of the clinical efficacy of the heart spectrum blood pressure monitor for diagnosis of atrial fibrillation: An unblinded clinical trial

PubMed Central

Kao, Wei-Fong; Hou, Sen-Kuang; Huang, Chun-Yao; Cheng, Chung-Chih; Chen, Yi-Jung

2018-01-01

Atrial fibrillation (AF) is the most common arrhythmia. The most common diagnostic method, 12-lead electrocardiogram (ECG), can record episodes of arrhythmia from which the type and severity can be determined. The Heart Spectrum Blood Pressure Monitor (P2; OSTAR Meditech Corp., New Taipei City, Taiwan) is used to measure cardiovascular pressure change with fast Fourier transform (FFT) analysis to obtain heart rate frequency variability and accurate blood pressure data. We compared the diagnostic efficacy of the Heart Spectrum Blood Pressure Monitor to a 12-lead ECG (gold standard) for patients with AF. Three measurement methods were used in this study to analyze the heart index and compare the results with simultaneous 12-lead ECG: blood pressure; mean arterial pressure, which was calculated from individual blood pressure as a constant pressure; and a constant pressure of 60 mmHg. The physician used a 12-lead ECG and the Heart Spectrum Blood Pressure Monitor simultaneously. The Heart Spectrum Blood Pressure Monitor used FFT analysis to diagnose AF, and the findings were compared to the 12-lead ECG readings. This unblinded clinical trial was conducted in the emergency department of Taipei Medical University Hospital. Twenty-nine subjects with AF and 33 without AF aged 25 to 97 y (mean, 63.5 y) were included. Subjects who were exposed to high-frequency surgical equipment during testing, those with cardiac pacemakers or implantable defibrillators, and pregnant women were excluded. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 97%, 97%, 97%, and 97%, respectively, for method 1; 90%, 100%, 100%, and 91%, respectively, for method 2; and 100%, 94%, 94%, and 100%, respectively, for method 3. The sensitivity, specificity, PPV, and NPV for both methods ranged between 90% and 100%, indicating that the Heart Spectrum Blood Pressure Monitor can be effectively applied for AF detection. PMID:29902218

Atrial Fibrillation

MedlinePlus

... pain Dizziness or fainting Fatigue Confusion AF can lead to an increased risk of stroke. In many patients, it can also cause chest pain, heart attack, or heart failure. Doctors diagnose AF using family and medical history, a physical exam, and a test called an ...

Surgical treatment of atrial fibrillation.

PubMed

Pagé, Pierre; Skanes, Allan C

2005-09-01

Surgery aims to eliminate atrial fibrillation (AF) through direct modification of the arrhythmogenic substratum. The Maze procedure, developed two decades ago, has proven to be clearly effective in restoring sinus rhythm in AF patients with or without associated organic cardiac disorders. Indications for surgery may be tailored to the clinical situation involved. In patients with continuous AF associated with structural heart disease (eg, valvular, congenital or coronary artery disease), the performance of a concomitant AF ablation procedure proven to add minimal morbidity to the operation may be highly beneficial to patient outcome. It is likely, although not entirely proven, that the restoration and maintenance of sinus rhythm after mitral valve surgery promotes survival by preventing tachycardia-induced cardiomyopathy and stroke. Novel strategies for AF surgery involve the use of alternate energy sources to create the lines of block in the atria and the simplification of the lesion pattern compared with the earlier Cox-Maze procedure. Published clinical data support the contention that left atrial ablation techniques performed concomitantly with valvular and/or coronary artery bypass surgery are likely to result in a 70% to 90% cure rate of AF in patients with preoperatively documented AF. Despite the lack of evidence for long-term outcome benefit, intraoperative pulmonary vein ablation, feasible with minimal morbidity, clearly appears to be an improvement over simply ignoring AF in patients undergoing cardiac surgery. Left atrial appendectomy appears warranted in patients with chronic persistent AF.

Clinical, biomarker, and genetic predictors of specific types of atrial fibrillation in a community-based cohort: data of the PREVEND study.

PubMed

Hobbelt, Anne H; Siland, Joylene E; Geelhoed, Bastiaan; Van Der Harst, Pim; Hillege, Hans L; Van Gelder, Isabelle C; Rienstra, Michiel

2017-02-01

Atrial fibrillation (AF) may present variously in time, and AF may progress from self-terminating to non-self-terminating AF, and is associated with impaired prognosis. However, predictors of AF types are largely unexplored. We investigate the clinical, biomarker, and genetic predictors of development of specific types of AF in a community-based cohort. We included 8042 individuals (319 with incident AF) of the PREVEND study. Types of AF were compared, and multivariate multinomial regression analysis determined associations with specific types of AF. Mean age was 48.5 ± 12.4 years and 50% were men. The types of incident AF were ascertained based on electrocardiograms; 103(32%) were classified as AF without 2-year recurrence, 158(50%) as self-terminating AF, and 58(18%) as non-self-terminating AF. With multivariate multinomial logistic regression analysis, advancing age (P< 0.001 for all three types) was associated with all AF types, male sex was associated with AF without 2-year recurrence and self-terminating AF (P= 0.031 and P= 0.008, respectively). Increasing body mass index and MR-proANP were associated with both self-terminating (P= 0.009 and P< 0.001) and non-self-terminating AF (P= 0.003 and P< 0.001). The only predictor associated with solely self-terminating AF is prescribed anti-hypertensive treatment (P= 0.019). The following predictors were associated with non-self-terminating AF; lower heart rate (P= 0.018), lipid-lowering treatment prescribed (P= 0.009), and eGFR <60 mL/min/1.73 m2 (P= 0.006). Three known AF-genetic variants (rs6666258, rs6817105, and rs10821415) were associated with self-terminating AF. We found clinical, biomarker and genetic predictors of specific types of incident AF in a community-based cohort. The genetic background seems to play a more important role than modifiable risk factors in self-terminating AF.

International trends in clinical characteristics and oral anticoagulation treatment for patients with atrial fibrillation: Results from the GARFIELD-AF, ORBIT-AF I, and ORBIT-AF II registries.

PubMed

Steinberg, Benjamin A; Gao, Haiyan; Shrader, Peter; Pieper, Karen; Thomas, Laine; Camm, A John; Ezekowitz, Michael D; Fonarow, Gregg C; Gersh, Bernard J; Goldhaber, Samuel; Haas, Sylvia; Hacke, Werner; Kowey, Peter R; Ansell, Jack; Mahaffey, Kenneth W; Naccarelli, Gerald; Reiffel, James A; Turpie, Alexander; Verheugt, Freek; Piccini, Jonathan P; Kakkar, Ajay; Peterson, Eric D; Fox, Keith A A

2017-12-01

Atrial fibrillation (AF) is the most common cardiac arrhythmia in the world. We aimed to provide comprehensive data on international patterns of AF stroke prevention treatment. Demographics, comorbidities, and stroke risk of the patients in the GARFIELD-AF (n=51,270), ORBIT-AF I (n=10,132), and ORBIT-AF II (n=11,602) registries were compared (overall N=73,004 from 35 countries). Stroke prevention therapies were assessed among patients with new-onset AF (≤6 weeks). Patients from GARFIELD-AF were less likely to be white (63% vs 89% for ORBIT-AF I and 86% for ORBIT-AF II) or have coronary artery disease (19% vs 36% and 27%), but had similar stroke risk (85% CHA 2 DS 2 -VASc ≥2 vs 91% and 85%) and lower bleeding risk (11% with HAS-BLED ≥3 vs 24% and 15%). Oral anticoagulant use was 46% and 57% for patients with a CHA 2 DS 2 -VASc=0 and 69% and 87% for CHA 2 DS 2 -VASc ≥2 in GARFIELD-AF and ORBIT-AF II, respectively, but with substantial geographic heterogeneity in use of oral anticoagulant (range: 31%-93% [GARFIELD-AF] and 66%-100% [ORBIT-AF II]). Among patients with new-onset AF, non-vitamin K antagonist oral anticoagulant use increased over time to 43% in 2016 for GARFIELD-AF and 71% for ORBIT-AF II, whereas use of antiplatelet monotherapy decreased from 36% to 17% (GARFIELD-AF) and 18% to 8% (ORBIT-AF I and II). Among new-onset AF patients, non-vitamin K antagonist oral anticoagulant use has increased and antiplatelet monotherapy has decreased. However, anticoagulation is used frequently in low-risk patients and inconsistently in those at high risk of stroke. Significant geographic variability in anticoagulation persists and represents an opportunity for improvement. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Anticoagulation therapy and clinical outcomes in patients with recently diagnosed atrial fibrillation: Insights from the ARISTOTLE trial.

PubMed

Guimarães, Patrícia O; Wojdyla, Daniel M; Alexander, John H; Thomas, Laine; Alings, Marco; Flaker, Greg C; Al-Khatib, Sana M; Hanna, Michael; Horowitz, John D; Wallentin, Lars; Granger, Christopher B; Lopes, Renato D

2017-01-15

Evidence supporting use of antithrombotic therapy in atrial fibrillation (AF) is based mainly on data from patients with permanent, persistent, or paroxysmal AF. Less is known about the risk following a new diagnosis of AF and the efficacy and safety of apixaban in these patients. Using data from ARISTOTLE, we assessed the relationship between timing of AF diagnosis and clinical outcomes and the efficacy and safety of apixaban versus warfarin in these patients. Recently diagnosed AF was defined as a new diagnosis of AF within 30days prior to enrollment. Cox proportional hazards models were used to determine the association between recently diagnosed AF and clinical outcomes. We also assessed the efficacy and safety of apixaban versus warfarin according to time since AF diagnosis. In ARISTOTLE, 1899 (10.5%) patients had recently diagnosed AF. After adjustment, patients with recently versus remotely diagnosed AF had a similar risk of stroke/systemic embolism (HR=1.07, 95% CI=0.80-1.42; p=0.67), but higher mortality was seen in patients with recently diagnosed AF (adjusted HR=1.21, 95% CI=1.02-1.43; p=0.03). The beneficial effects of apixaban, compared with warfarin, on clinical outcomes were consistent, irrespective of timing of AF diagnosis (all interaction p-values >0.12). Patients with recently diagnosed AF had a similar risk of stroke but higher mortality than patients with remotely diagnosed AF, suggesting that they are not at "low risk" and warrant stroke prevention strategies. The benefits of apixaban over warfarin were preserved, irrespective of timing of AF diagnosis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Calreticulin overexpression correlates with integrin-α5 and transforming growth factor-β1 expression in the atria of patients with rheumatic valvular disease and atrial fibrillation.

PubMed

Zhao, Fei; Zhang, Shijiang; Shao, Yongfeng; Wu, Yanhu; Qin, Jianwei; Chen, Yijiang; Chen, Liang; Gu, Haitao; Wang, Xiaowei; Huang, Chenjun; Zhang, Wei

2013-10-03

The aim of this study was to determine whether altered calreticulin expression and distribution contribute to the pathogenesis of atrial fibrillation (AF) associated with valvular heart disease (VHD). AF affects electrophysiological and structural changes that exacerbate AF. Atrial remodeling reportedly underlies AF generation, but the precise mechanism of atrial remodeling in AF remains unclear. Right and left atrial specimens were obtained from 68 patients undergoing valve replacement surgery. The patients were divided into sinus rhythm (SR; n=25), paroxysmal AF (PaAF; n=11), and persistent AF (PeAF; AF lasting >6 months; n=32) groups. Calreticulin, integrin-α5, and transforming growth factor-β1 (TGF-β1) mRNA and protein expression were measured. We also performed immunoprecipitation for calreticulin with either calcineurin B or integrin-α5. Calreticulin, integrin-α5, and TGF-β1 mRNA and protein expression were increased in the AF groups, especially in the left atrium in patients with mitral valve disease. Calreticulin interacted with both calcineurin B and integrin-α5. Integrin-α5 expression correlated with TGF-β1 expression, while calreticulin expression correlated with integrin-α5 and TGF-β1 expression. Despite similar cardiac function classifications, calreticulin expression was greater in the PeAF group than in the SR group. Calreticulin, integrin-α5, and TGF-β1 expression was increased in atrial tissue in patients with AF and was related to AF type, suggesting that calreticulin is involved in the pathogenesis of AF in VHD patients. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Fish oil and postoperative atrial fibrillation: the Omega-3 Fatty Acids for Prevention of Post-operative Atrial Fibrillation (OPERA) randomized trial.

PubMed

Mozaffarian, Dariush; Marchioli, Roberto; Macchia, Alejandro; Silletta, Maria G; Ferrazzi, Paolo; Gardner, Timothy J; Latini, Roberto; Libby, Peter; Lombardi, Federico; O'Gara, Patrick T; Page, Richard L; Tavazzi, Luigi; Tognoni, Gianni

2012-11-21

Postoperative atrial fibrillation or flutter (AF) is one of the most common complications of cardiac surgery and significantly increases morbidity and health care utilization. A few small trials have evaluated whether long-chain n-3-polyunsaturated fatty acids (PUFAs) reduce postoperative AF, with mixed results. To determine whether perioperative n-3-PUFA supplementation reduces postoperative AF. The Omega-3 Fatty Acids for Prevention of Post-operative Atrial Fibrillation (OPERA) double-blind, placebo-controlled, randomized clinical trial. A total of 1516 patients scheduled for cardiac surgery in 28 centers in the United States, Italy, and Argentina were enrolled between August 2010 and June 2012. Inclusion criteria were broad; the main exclusions were regular use of fish oil or absence of sinus rhythm at enrollment. Patients were randomized to receive fish oil (1-g capsules containing ≥840 mg n-3-PUFAs as ethyl esters) or placebo, with preoperative loading of 10 g over 3 to 5 days (or 8 g over 2 days) followed postoperatively by 2 g/d until hospital discharge or postoperative day 10, whichever came first. Occurrence of postoperative AF lasting longer than 30 seconds. Secondary end points were postoperative AF lasting longer than 1 hour, resulting in symptoms, or treated with cardioversion; postoperative AF excluding atrial flutter; time to first postoperative AF; number of AF episodes per patient; hospital utilization; and major adverse cardiovascular events, 30-day mortality, bleeding, and other adverse events. At enrollment, mean age was 64 (SD, 13) years; 72.2% of patients were men, and 51.8% had planned valvular surgery. The primary end point occurred in 233 (30.7%) patients assigned to placebo and 227 (30.0%) assigned to n-3-PUFAs (odds ratio, 0.96 [95% CI, 0.77-1.20]; P = .74). None of the secondary end points were significantly different between the placebo and fish oil groups, including postoperative AF that was sustained, symptomatic, or treated (231 [30.5%] vs 224 [29.6%], P = .70) or number of postoperative AF episodes per patient (1 episode: 156 [20.6%] vs 157 [20.7%]; 2 episodes: 59 [7.8%] vs 49 [6.5%]; ≥3 episodes: 18 [2.4%] vs 21 [2.8%]) (P = .73). Supplementation with n-3-PUFAs was generally well tolerated, with no evidence for increased risk of bleeding or serious adverse events. In this large multinational trial among patients undergoing cardiac surgery, perioperative supplementation with n-3-PUFAs, compared with placebo, did not reduce the risk of postoperative AF. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00970489.

Phase synchrony reveals organization in human atrial fibrillation

PubMed Central

Vidmar, David; Narayan, Sanjiv M.

2015-01-01

It remains unclear if human atrial fibrillation (AF) is spatially nonhierarchical or exhibits a hierarchy of organization sustained by sources. We utilize activation times obtained at discrete locations during AF to compute the phase synchrony between tissue regions, to examine underlying spatial dynamics throughout both atria. We construct a binary synchronization network and show that this network can accurately define regions of coherence in coarse-grained in silico data. Specifically, domains controlled by spiral waves exhibit regions of high phase synchrony. We then apply this analysis to clinical data from patients experiencing cardiac arrhythmias using multielectrode catheters to simultaneously record from a majority of both atria. We show that pharmaceutical intervention with ibutilide organizes activation by increasing the size of the synchronized domain in AF and quantify the increase in temporal organization when arrhythmia changes from fibrillation to tachycardia. Finally, in recordings from 24 patients in AF we show that the level of synchrony is spatially broad with some patients showing large spatially contiguous regions of synchronization, while in others synchrony is localized to small pockets. Using computer simulations, we show that this distribution is inconsistent with distributions obtained from simulations that mimic multiwavelet reentry but is consistent with mechanisms in which one or more spatially conserved spiral waves is surrounded by tissue in which activation is disorganized. PMID:26475585

Using an Atrial Fibrillation Decision Support Tool for Thromboprophylaxis in Atrial Fibrillation: Effect of Sex and Age.

PubMed

Eckman, Mark H; Lip, Gregory Y H; Wise, Ruth E; Speer, Barbara; Sullivan, Megan; Walker, Nita; Kissela, Brett; Flaherty, Matthew L; Kleindorfer, Dawn; Baker, Peter; Ireton, Robert; Hoskins, Dave; Harnett, Brett M; Aguilar, Carlos; Leonard, Anthony; Arduser, Lora; Steen, Dylan; Costea, Alexandru; Kues, John

2016-05-01

To assess the appropriateness of oral anticoagulant therapy (OAT) in women and elderly adults, looking for patterns of undertreatment or unnecessary treatment. Retrospective cohort study. Primary care practices of an academic healthcare system. Adults (aged 28-93) with nonvalvular atrial fibrillation (AF) seen between March 2013 and February 2014 (N = 1,585). Treatment recommendations were made using an AF decision support tool (AFDST) based on projections of quality-adjusted life expectancy calculated using a decision analytical model that integrates individual-specific risk factors for stroke and hemorrhage. Treatment was discordant from AFDST-recommended treatment in 45% (326/725) of women and 39% (338/860) of men (P = .02). Although current treatment was discordant from recommended in 35% (89/258) of participants aged 85 and older and in 43% (575/1,328) of those younger than 85 (P = .01), many undertreated elderly adults were receiving aspirin as the sole antithrombotic agent. Physicians should understand that female sex is a significant risk factor for AF-related stroke and incorporate this into decision-making about thromboprophylaxis. Treating older adults with aspirin instead of OAT exposes them to significant risk of bleeding with little to no reduction in AF-related stroke risk. © 2016, Copyright the Authors Journal compilation © 2016, The American Geriatrics Society.

Platelets Cellular and Functional Characteristics in Patients with Atrial Fibrillation: A Comprehensive Meta-Analysis and Systematic Review

PubMed Central

Weymann, Alexander; Ali-Hasan-Al-Saegh, Sadeq; Sabashnikov, Anton; Popov, Aron-Frederik; Mirhosseini, Seyed Jalil; Nombela-Franco, Luis; Testa, Luca; Lotfaliani, Mohammadreza; Zeriouh, Mohamed; Liu, Tong; Dehghan, Hamidreza; Yavuz, Senol; de Oliveira Sá, Michel Pompeu Barros; Baker, William L.; Jang, Jae-Sik; Gong, Mengqi; Benedetto, Umberto; Dohmen, Pascal M.; D’Ascenzo, Fabrizio; Deshmukh, Abhishek J.; Biondi-Zoccai, Giuseppe; Calkins, Hugh; Stone, Gregg W.

2017-01-01

Background This systematic review with meta-analysis aimed to determine the strength of evidence for evaluating the association of platelet cellular and functional characteristics including platelet count (PC), MPV, platelet distribution width (PDW), platelet factor 4, beta thromboglobulin (BTG), and p-selectin with the occurrence of atrial fibrillation (AF) and consequent stroke. Material/Methods We conducted a meta-analysis of observational studies evaluating platelet characteristics in patients with paroxysmal, persistent and permanent atrial fibrillations. A comprehensive subgroup analysis was performed to explore potential sources of heterogeneity. Results Literature search of all major databases retrieved 1,676 studies. After screening, a total of 73 studies were identified. Pooled analysis showed significant differences in PC (weighted mean difference (WMD)=−26.93 and p<0.001), MPV (WMD=0.61 and p<0.001), PDW (WMD=−0.22 and p=0.002), BTG (WMD=24.69 and p<0.001), PF4 (WMD=4.59 and p<0.001), and p-selectin (WMD=4.90 and p<0.001). Conclusions Platelets play a critical and precipitating role in the occurrence of AF. Whereas distribution width of platelets as well as factors of platelet activity was significantly greater in AF patients compared to SR patients, platelet count was significantly lower in AF patients. PMID:28302997

Attitudes toward Catheter Ablation for Atrial Fibrillation: A Nationwide Survey among Danish Cardiologists.

PubMed

Vadmann, Henrik; Pedersen, Susanne S; Nielsen, Jens Cosedis; Rodrigo-Domingo, Maria; Pehrson, Steen; Johannessen, Arne; Hansen, Peter Steen; Johansen, Jens Brock; Riahi, Sam

2015-10-01

Catheter ablation for atrial fibrillation (AF) is an important but expensive procedure that is the subject of some debate. Physicians' attitudes toward catheter ablation may influence promotion and patient acceptance. This is the first study to examine the attitudes of Danish cardiologists toward catheter ablation for AF, using a nationwide survey. We developed a purpose-designed questionnaire to evaluate attitudes toward catheter ablation for AF that was sent to all Danish cardiologists (n = 401; response n = 272 (67.8%)). There was no association between attitudes toward ablation and the experience or age of the cardiologist with respect to patients with recurrent AF episodes with a duration of <48 hours or >7 days and/or need for cardioversion. The majority (69%) expected a recurrence of AF after catheter ablation in more than 30% of the cases. For patients with persistent longstanding AF with a duration of >1 year, the attitude toward ablation for longstanding AF was more likely to be positive with increasing age (P < 0.01) and years of experience of the cardiologist (P = 0.002). Danish cardiologists generally have a positive attitude toward catheter ablation for AF, maintain up-to-date knowledge of the procedure, and are aware what information on ablation treatment should be given to patients with AF. The cardiologists had a positive attitude toward ablation for AF in patients with AF episodes <48 hours and patients with episodes >7 days, or those who needed medical/electrical conversion, but a more negative attitude toward treating longstanding AF patients. © 2015 Wiley Periodicals, Inc.

Incidence, predictive factors, management, and survival impact of atrial fibrillation in non-Hodgkin lymphoma.

PubMed

Sorigue, Marc; Gual-Capllonch, Francisco; Garcia, Olga; Sarrate, Edurne; Franch-Sarto, Mireia; Ibarra, Gladys; Grau, Javier; Orna, Elisa; Ribera, Josep-Maria; Sancho, Juan-Manuel

2018-05-04

Atrial fibrillation (AF) and cancer are common disorders in the general population but there are few studies in patients with both diseases. More specifically, there are scarce data on AF in patients with non-Hodgkin lymphoma (NHL). We assessed the incidence, predictive factors, management, and survival impact of AF in a cohort of patients with NHL from a single institution between 2002 and 2016 (n = 747). Twenty-three patients were diagnosed with AF before and 40 after the diagnosis of NHL (of the later, 16 were secondary to an extracardiac comorbidity and 24 unrelated to any triggering event [primary AF]). The 5-year cumulative incidence of new-onset AF was 4% (95% confidence interval [CI] 3-6%). Age and hypertension were the only predictive factors for the development of AF. Management of AF was heterogeneous, primarily with anti-vitamin K agents but also antiplatelet therapy in a significant proportion of patients. Among the 63 patients, there were six episodes of ischemic stroke/transient ischemic attack and four venous thromboembolic events, with four major bleeding episodes. Overall survival (OS) was inferior in patients with AF (HR 0.1, 95% CI 0.01-0.7, p = 0.02), largely due to secondary AF. We conclude that the incidence of new-onset AF in NHL patients seemed somewhat higher than in the general population, although with similar predictive factors. The management was heterogeneous, and the risk of ischemic and hemorrhagic events did not seem higher than in cancer-free patients. Survival was particularly poor for patients with secondary AF.

Remodeling of Kv1.5 channel in right atria from Han Chinese patients with atrial fibrillation.

PubMed

Ou, Xian-hong; Li, Miao-ling; Liu, Rui; Fan, Xin-rong; Mao, Liang; Fan, Xue-hui; Yang, Yan; Zeng, Xiao-rong

2015-04-28

The incidence of atrial fibrillation (AF) in rheumatic heart diseases (RHD) is very high and increases with age. Occurrence and maintenance of AF are very complicated process accompanied by many different mechanisms. Ion-channel remodeling, including the voltage-gated potassium channel Kv1.5, plays an important role in the pathophysiology of AF. However, the changes of Kv1.5 channel expression in Han Chinese patients with RHD and AF remain poorly understood. The aim of the present study was to investigate whether the Kv1.5 channels of the right atria may be altered with RHD, age, and sex to contribute to AF. Right atrial appendages were obtained from 20 patients with normal cardiac functions who had undergone surgery, and 26 patients with AF. Subjects were picked from 4 groups: adult and aged patients in normal sinus rhythm (SR) and AF. Patients were divided into non-RHD and RHD groups or men and women groups in normal SR and AF, respectively. The expression of Kv1.5 protein and messenger RNA (mRNA) were measured using Western blotting and polymerase chain reaction (PCR) method, respectively. Compared with the SR group, the expression of Kv1.5 protein decreased significantly in the AF group. However, neither Kv1.5 protein nor KCNA5 mRNA had significant differences in adult and aged groups, non-RHD and RHD group, and men and women group of AF. The expression of Kv1.5 channel protein changes with AF but not with age, RHD, and sex in AF.

Impact of atrial fibrillation on stroke-related healthcare costs.

PubMed

Sussman, Matthew; Menzin, Joseph; Lin, Iris; Kwong, Winghan J; Munsell, Michael; Friedman, Mark; Selim, Magdy

2013-11-25

Limited data exist on the economic implications of stroke among patients with atrial fibrillation (AF). This study assesses the impact of AF on healthcare costs associated with ischemic stroke (IS), hemorrhagic stroke (HS), or transient ischemic attack (TIA). A retrospective analysis of MarketScan claims data (2005-2011) for AF patients ≥18 years old with ≥1 inpatient claim for stroke, or ≥1 ED or inpatient claim for TIA as identified by ICD-9-CM codes who had ≥12 months continuous enrollment prior to initial stroke. Initial event- and stroke-related costs 12 months post-index were compared among patients with AF and without AF. Adjusted costs were estimated, controlling for demographics, comorbidities, anticoagulant use, and baseline resource use. Data from 23,807 AF patients and 136,649 patients without AF were analyzed. Unadjusted mean cost of the index event was $20,933 for IS, $59,054 for HS, $8616 for TIA hospitalization, and $3395 for TIA ED visit. After controlling for potential confounders, adjusted mean incremental costs (index plus 12-month post-index) for AF patients were higher than those for non-AF patients by: $4726, $7824, and $1890 for index IS, HS, TIA (identified by hospitalization), respectively, and $1700 for TIA (identified by ED) (all P<0.01). In multivariate regression analysis, AF was associated with a 20% (IS), 13% (HS), and 18% (TIA) increase in total stroke-related costs. Stroke-related care for IS, HS, and TIA is costly, especially among individuals with AF. Reducing the risk of AF-related stroke is important from both clinical and economic standpoints.

Stroke prevention strategies in patients with atrial fibrillation and heart valve abnormalities: perceptions of 'valvular' atrial fibrillation: results of the European Heart Rhythm Association Survey.

PubMed

Potpara, Tatjana S; Lip, Gregory Y H; Larsen, Torben B; Madrid, Antonio; Dobreanu, Dan; Jędrzejczyk-Patej, Ewa; Dagres, Nikolaos

2016-10-01

The purpose of this European Heart Rhythm Association (EHRA) Survey was to assess the perceptions of 'valvular' atrial fibrillation (AF) and management of AF patients with various heart valve abnormalities in daily clinical practice in European electrophysiology (EP) centres. Questionnaire survey was sent via the Internet to the EHRA-EP Research Network Centres. Of the 52 responding centres, 42 (80.8%) were university hospitals. Choosing the most comprehensive definition of valvular AF, a total of 49 centres (94.2%) encountered a mechanical prosthetic heart valve and significant rheumatic mitral stenosis, 35 centres (67.3%) also considered bioprosthetic valves, and 25 centres (48.1%) included any significant valvular heart disease, requiring surgical repair in the definition of valvular AF. Only three centres (5.8%) would define valvular AF as the presence of any (even mild) valvular abnormality. None of the centres would use non-vitamin K antagonist oral anticoagulants (NOACs) in AF patients with mechanical prosthetic valves, only 5 centres (9.8%) would use NOACs in patients with significant mitral stenosis, 17 centres (32.7%) would consider the use of NOACs in patients with bioprosthetic valves, and 21 centres (41.2%) would use NOACs in patients with a non-recent transcatheter valve replacement/implantation, while 13 centres (25.5%) would never consider the use of NOACs in AF patients with even mild native heart valve abnormality. Our survey showed marked heterogeneity in the definition of valvular AF and thromboprophylactic treatments, with the use of variable NOACs in patients with valvular heart disease other than prosthetic heart valves or significant mitral stenosis, indicating that this term may be misleading and should not be used. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

Effect of hyperthyroidism on the hypercoagulable state and thromboembolic events in patients with atrial fibrillation.

PubMed

Chen, Qingxing; Yan, Yan; Zhang, Lei; Cheng, Kuan; Liu, Yuping; Zhu, Wenqing

2014-01-01

To clarify whether hyperthyroidism (HT) itself confers an additional effect on the hypercoagulable state and the risk of ischemic stroke among patients with hyperthyroid atrial fibrillation (AF). We prospectively evaluated plasma D-dimer levels and thromboembolic events among three groups of patients (hyperthyroid AF, n = 62; nonthyroid AF, n = 107, and HT without AF, n = 100). Plasma D-dimer levels were used to evaluate the hypercoagulable state. The D-dimer level was significantly higher in patients with hyperthyroid AF than in nonthyroid AF (0.66 ± 0.06 vs. 0.34 ± 0.02 mg/l, p < 0.001) and HT without AF (0.66 ± 0.06 vs. 0.27 ± 0.02 mg/l, p < 0.001). During a 3-year follow-up, patients with hyperthyroid AF had a significantly higher incidence of ischemic stroke compared with patients with nonthyroid AF (hazard ratio, HR: 3.2, 95% confidence interval, CI: 1.01-5.59, p = 0.04). Cox regression analysis revealed that age (HR: 2.5, 95% CI: 1.01-1.21, p = 0.05), CHADS2-VAS score (HR: 5.5, 95% CI: 1.51-7.43, p = 0.01) and anticoagulation (HR: 0.45, 95% CI: 0.07-0.54, p = 0.01) were independent predictors of risk for the occurrence of ischemic stroke. The present study suggests that HT may enhance the hypercoagulable state and the risk of ischemic stroke in patients with AF.

Left ventricular stiffness estimated by diastolic wall strain is associated with paroxysmal atrial fibrillation in structurally normal hearts.

PubMed

Uetake, Shunsuke; Maruyama, Mitsunori; Yamamoto, Teppei; Kato, Katsuhito; Miyauchi, Yasushi; Seino, Yoshihiko; Shimizu, Wataru

2016-12-01

Left ventricular (LV) diastolic dysfunction depends on an impaired relaxation and stiffness. Abnormal LV relaxation contributes to the development of atrial fibrillation (AF), but the role of LV stiffness in AF remains unclear. Diastolic wall strain (DWS), a load-independent, noninvasive direct measure of LV stiffness, correlates with prevalent AF. This study included 328 consecutive subjects with structurally normal hearts: 164 paroxysmal AF patients and 164 age- and sex-matched (1:1) controls. We calculated the DWS from the M-mode echocardiographic measurements of the LV posterior wall thickness at end-systole and end-diastole during sinus rhythm. The DWS was lower in the AF patients (0.35 ± 0.07) than in the controls (0.41 ± 0.06; P < 0.001). After adjusting for the risk factors of AF using a conditional logistic regression analysis, a history of hypertension, plasma brain-type natriuretic peptide level, and DWS were independently associated with AF prevalence, whereas body mass index, LV mass index, left atrial volume, and any conventional indices of the diastolic function were not. A low DWS (<0.380) was the strongest indicator of AF (odds ratio: 6.22, 95% confidence interval: 3.08-14.2, P < 0.001). Increased LV stiffness estimated by DWS was a strong determinant of the prevalence of AF. LV stiffness may play a role in the pathogenesis of paroxysmal AF in structurally normal hearts. © 2016 Wiley Periodicals, Inc.

Characteristics and Prognosis of Pacemaker-Identified New-Onset Atrial Fibrillation in Japanese People.

PubMed

Ogino, Yutaka; Ishikawa, Toshiyuki; Ishigami, Tomoaki; Matsumoto, Katsumi; Hosoda, Junya; Iguchi, Kouhei; Matsushita, Hirooki; Taguchi, Yuka; Horiguchi, Yoriko; Kimura, Kazuo

2017-05-25

The characteristics and prognosis of implanted pacemaker-identified new-onset atrial fibrillation (AF) in Japanese people has not been well evaluated.Methods and Results:A total of 395 consecutive patients with newly implanted pacemakers were retrospectively analyzed between January 2010 and December 2015 at Yokohama City University Hospital. Patients with a prior history of AF, VVI mode pacemaker, congenital heart disease, severe valvular heart disease, and cardiovascular surgery before pacemaker implantation were excluded. Among the remaining patients, 44 (21.3%) developed new AF during follow-up (mean follow-up, 1,115±651 days; range, 9-2,176 days). Patients with new-onset AF had a significantly higher CHADS 2 score (2.09±1.27 vs. 1.31±1.08, P<0.001) and CHA 2 DS 2 -VASc score (3.00±1.39 vs. 2.26±1.19, P<0.001) compared with those without new-onset AF. On Cox regression analysis only age at implantation was significantly correlated with new-onset AF. Interestingly, the incidence of hospitalization due to heart failure was significantly higher in the new-onset AF than in the without new-onset AF group. A total of 21.3% of pacemaker-implanted patients with high CHADS 2 and CHA 2 DS 2 -VASc scores developed new-onset AF during a mean follow-up of 3.1 years; and pacemaker-identified AF was associated with an increased risk of worsening heart failure.

Comparison of the origin and coupling interval between ectopy with and without atrial fibrillation initiation.

PubMed

Kanda, Takashi; Masuda, Masaharu; Fujita, Masashi; Iida, Osamu; Okamoto, Shin; Ishihara, Takayuki; Nanto, Kiyonori; Sunaga, Akihiro; Tsujimura, Takuya; Matsuda, Yasuhiro; Ohashi, Takuya; Uematsu, Masaaki

2018-01-01

Differentiation of atrial fibrillation (AF) trigger ectopy from other ectopy is often difficult. The purpose of this study was to compare the origin and coupling intervals (CI) between AF-trigger and non-AF-trigger ectopy. This study consisted of 120 patients with AF who underwent an initial ablation. Isoproterenol was infused up to 20μg/min to provoke ectopy and AF. We measured the CI of all ectopy provoked by an isoproterenol infusion. The %CI was calculated as the CI of the ectopy/P-P interval of the preceding 2 beats. A total of 117 patients had at least one ectopy, and AF was induced in 56 (47%) patients. Of the 276 ectopies observed in this study, 211 (76%) originated from pulmonary veins and 77 (28%) were AF-trigger ectopy. AF-trigger ectopy more frequently originated from pulmonary veins (PVs) (74 vs. 3, p<0.001) and had a significantly shorter CI (201±70ms vs. 365±147ms, p<0.001) and lower %CI (29±11% vs. 55±14%, p<0.001) than that of non-AF-trigger ectopy. A receiver operating characteristics analysis revealed that a %CI of 40% was the best cut-off value for differentiating whether it was an AF-trigger or not. The identified trigger group, including patients with provoked AF-trigger ectopy or ectopy with a low %CI (<40%), had a significantly better AF recurrence-free survival rate than the other group (88% vs. 65%, p=0.004). AF-trigger ectopy predominantly originated from PVs and had a short CI. These findings may be useful for estimating whether ectopies are an AF-trigger or not. Copyright © 2017 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Impact of Atrial Fibrillation on Healthcare Utilization in the Community: The Atherosclerosis Risk in Communities Study

PubMed Central

Bengtson, Lindsay G. S.; Lutsey, Pamela L.; Loehr, Laura R.; Kucharska‐Newton, Anna; Chen, Lin Y.; Chamberlain, Alanna M.; Wruck, Lisa M.; Duval, Sue; Stearns, Sally C.; Alonso, Alvaro

2014-01-01

Background Atrial fibrillation (AF) is associated with increased risk of hospitalization. Little is known about the impact of AF on utilization of noninpatient health care or about sex or race differences in AF‐related utilization. We examined rates of inpatient and outpatient utilization by AF status in the Atherosclerosis Risk in Communities study. Methods and Results Participants with incident AF enrolled in fee‐for‐service Medicare for at least 12 continuous months between 1991 and 2009 (n=932) were matched on age, sex, race and field center with up to 3 participants without AF (n=2729). Healthcare utilization was ascertained from Medicare claims and classified by primary International Classification of Diseases, ninth revision code. The average annual numbers of days hospitalized were 13.2 (95% CI 11.6 to 15.0) and 2.8 (95% CI 2.5 to 3.1) for those with and without AF, respectively. The corresponding numbers of annual outpatient claims were 53.3 (95% CI 50.5 to 56.3) and 22.9 (95% CI 22.1 to 23.8) for those with and without AF, respectively. Most utilization among AF patients was attributable to non‐AF conditions. The adjusted rate ratio for annual days hospitalized for other cardiovascular disease–related reasons was 4.58 (95% CI: 3.41 to 6.16) for those with AF versus those without AF. The association between AF and healthcare utilization was similar among men and women and among white and black participants. Conclusions Participants with AF had considerably greater healthcare utilization, and the difference in utilization for other cardiovascular disease–related reasons was substantial. In addition to rate or rhythm treatment, AF management should focus on the accompanying cardiovascular comorbidities. PMID:25359400

Increasing atrial fibrillation prevalence in acute ischemic stroke and TIA.

PubMed

Otite, Fadar Oliver; Khandelwal, Priyank; Chaturvedi, Seemant; Romano, Jose G; Sacco, Ralph L; Malik, Amer M

2016-11-08

To evaluate trends in atrial fibrillation (AF) prevalence in acute ischemic stroke (AIS) and TIA in the United States. We used the Nationwide Inpatient Sample to retrospectively compute weighted prevalence of AF in AIS (n = 4,355,140) and TIA (n = 1,816,459) patients admitted to US hospitals from 2004 to 2013. Multivariate-adjusted models were used to evaluate the association of AF with clinical factors, mortality, length of stay, and cost. From 2004 to 2013, AF prevalence increased by 22% in AIS (20%-24%) and by 38% in TIA (12%-17%). AF prevalence varied by age (AIS: 6% in 50-59 vs 37% in ≥80 years; TIA: 4% in 50-59 vs 24% in ≥80 years), sex (AIS: male 19% vs female 25%; TIA: male 15% vs female 14%), race (AIS: white 26% vs black 12%), and region (AIS: Northeast 25% vs South 20%). Advancing age, female sex, white race, high income, and large hospital size were associated with increased odds of AF in AIS. AF in AIS was a risk factor for in-hospital death (odds ratio 1.93, 95% confidence interval 1.89-1.98) but mortality in AIS with AF decreased from 11.6% to 8.3% (p < 0.001). Compared to no AF, AF was associated with increased cost of $2,310 and length of stay 1.1 days in AIS. AF prevalence in AIS and TIA has continued to increase. Disparity in AF prevalence in AIS and TIA exists by patient and hospital factors. AF is associated with increased mortality in AIS. Innovative AIS preventive strategies are needed in patients with AF, especially in the elderly. © 2016 American Academy of Neurology.

Benefit of Anticoagulation Therapy in Hyperthyroidism-Related Atrial Fibrillation.

PubMed

Chan, Pak-Hei; Hai, Jojo; Yeung, Chun-Yip; Lip, Gregory Y H; Lam, Karen Siu-Ling; Tse, Hung-Fat; Siu, Chung-Wah

2015-08-01

Existing data on the risk of ischemic stroke in hyperthyroidism-related atrial fibrillation (AF) and the impact of long-term anticoagulation in these patients, particularly those with self-limiting AF, remain inconclusive. Risk of stroke in hyperthyroidism-related AF is the same as nonhyperthyroid counterparts. This was a single-center observational study of 9727 Chinese patients with nonvalvular AF from July 1997 to December 2011. Patients with AF diagnosed concomitantly with hyperthyroidism were identified. Primary and secondary endpoints were defined as hospitalization with ischemic stroke and intracranial hemorrhage in the first 2 years. Patient characteristics, duration of AF, and choice of antithrombotic therapy were recorded. Self-limiting AF was defined as <7 days' duration. Out of 9727 patients, 642 (6.6%) had concomitant hyperthyroidism and AF at diagnosis. For stroke prevention, 136 and 243 patients (21.1% and 37.9%) were prescribed warfarin and aspirin, respectively, whereas the remaining patients (41.0%) received no therapy. Ischemic stroke occurred in 50 patients (7.8%), and no patient developed hemorrhagic stroke. Patients with CHA2 DS2 -VASc of 0 did not develop stroke. Warfarin effectively reduced the incidence of stroke compared with aspirin or no therapy in patients with CHA2 DS2 -VASc ≥1 and non-self-limiting AF, but not in those with self-limiting AF or CHA2 DS2 -VASc of 0. Presence of hyperthyroidism did not confer additional risk of ischemic stroke compared with nonhyperthyroid AF. Patients with hyperthyroidism-related AF are at high risk of stroke (3.9% per year). Warfarin confers stroke prevention in patients with CHA2 DS2 -VASc ≥1 and non-self-limiting AF. Overall stroke risk was lower in hyperthyroid non-self-limiting AF patients compared with nonhyperthyroid counterparts. © 2015 Wiley Periodicals, Inc.

Influence of atrial fibrillation on the mortality of patients with heart failure with preserved ejection fraction.

PubMed

Franco, Jonathan; Formiga, Francesc; Cepeda, Jose; Llacer, Pau; Arévalo-Lorido, Juan; Cerqueiro, Jose; González-Franco, Alvaro; Epelde, Francesc; Manzano, Luis; Montero Pérez-Barquero, Manuel

2018-05-23

The impact of atrial fibrillation (AF) on the prognosis of heart failure with preserved ejection fraction (HFpEF) is still the subject of debate. We analysed the influence of AF on the prognosis on mortality and readmission in patients with HFpEF. Prospective observational study in 1,971 patients with HFpEF, who were admitted for acute heart failure. Patients were divided into 2 groups according to the presence or absence of AF. We analysed mortality, readmissions and combined mortality/readmissions at one year follow-up. A total of 1,177 (59%) patients had AF, mean age 80.3 (7.8) years and 1,233 (63%) were women. Patients with HFpEF and AF were older, female, greater valvular aetiology and lower comorbidity measured by the Charlson index. At the one year follow-up, 430 (22%) patients had died and 840 (43%) had been readmitted. In the 2 groups analysed, there was no difference in all-cause mortality (22 vs. 21%; P=.739, AF vs. no-AF, respectively) or cardiovascular causes (9.6 vs. 8.2%; P=.739, AF vs. no-AF, respectively). In the multivariable analysis, factors associated with higher mortality were: age, male, valvular aetiology, uric acid, and comorbidity. In the analysis of the subgroup with HFpEF with AF, the presence of chronic AF compared to de novo AF was associated with higher mortality (HR 1,716; 95% CI 1,099-2,681; P=.018). In patients with HFpEF, the presence of AF is frequent. During the one-year follow-up, the presence of AF does not influence mortality or readmissions in patients with HFpEF. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

Atrial Fibrillation in Hypertrophic Cardiomyopathy: Prevalence, Clinical Correlations, and Mortality in a Large High‐Risk Population

PubMed Central

Siontis, Konstantinos C.; Geske, Jeffrey B.; Ong, Kevin; Nishimura, Rick A.; Ommen, Steve R.; Gersh, Bernard J.

2014-01-01

Background Atrial fibrillation (AF) is a common sequela of hypertrophic cardiomyopathy (HCM), but evidence on its prevalence, risk factors, and effect on mortality is sparse. We sought to evaluate the prevalence of AF, identify clinical and echocardiographic correlates, and assess its effect on mortality in a large high‐risk HCM population. Methods and Results We identified HCM patients who underwent evaluation at our institution from 1975 to 2012. AF was defined by known history (either chronic or paroxysmal), electrocardiogram, or Holter monitoring at index visit. We examined clinical and echocardiographic variables in association with AF. The effect of AF on overall and cause‐specific mortality was evaluated with multivariate Cox proportional hazards models. Of 3673 patients with HCM, 650 (18%) had AF. Patients with AF were older and more symptomatic (P<0.001). AF was less common among patients with obstructive HCM phenotype and was associated with larger left atria, higher E/e’ ratios, and worse cardiopulmonary exercise tolerance (all P values<0.001). During median (interquartile range) follow‐up of 4.1 (0.2 to 10) years, 1069 (29%) patients died. Patients with AF had worse survival compared to those without AF (P<0.001). In multivariate analysis adjusted for established risk factors of mortality in HCM, the hazard ratio (95% confidence interval) for the effect of AF on overall mortality was 1.48 (1.27 to 1.71). AF did not have an effect on sudden or nonsudden cardiac death. Conclusions In this large referral HCM population, approximately 1 in 5 patients had AF. AF was a strong predictor of mortality, even after adjustment for established risk factors. PMID:24965028

Developing the Safety of Atrial Fibrillation Ablation Registry Initiative (SAFARI) as a collaborative pan-stakeholder critical path registry model: a Cardiac Safety Research Consortium "Incubator" Think Tank.

PubMed

Al-Khatib, Sana M; Calkins, Hugh; Eloff, Benjamin C; Kowey, Peter; Hammill, Stephen C; Ellenbogen, Kenneth A; Marinac-Dabic, Danica; Waldo, Albert L; Brindis, Ralph G; Wilbur, David J; Jackman, Warren M; Yaross, Marcia S; Russo, Andrea M; Prystowsky, Eric; Varosy, Paul D; Gross, Thomas; Pinnow, Ellen; Turakhia, Mintu P; Krucoff, Mitchell W

2010-10-01

Although several randomized clinical trials have demonstrated the safety and efficacy of catheter ablation of atrial fibrillation (AF) in experienced centers, the outcomes of this procedure in routine clinical practice and in patients with persistent and long-standing persistent AF remain uncertain. Brisk adoption of this therapy by physicians with diverse training and experience highlights potential concerns regarding the safety and effectiveness of this procedure. Some of these concerns could be addressed by a national registry of AF ablation procedures such as the Safety of Atrial Fibrillation Ablation Registry Initiative that was initially proposed at a Cardiac Safety Research Consortium Think Tank meeting in April 2009. In January 2010, the Cardiac Safety Research Consortium, in collaboration with the Duke Clinical Research Institute, the US Food and Drug Administration, the American College of Cardiology, and the Heart Rhythm Society, held a follow-up meeting of experts in the field to review the construct and progress to date. Other participants included the National Heart, Lung, and Blood Institute; the Centers for Medicare and Medicaid Services; the Agency for Healthcare Research and Quality; the AdvaMed AF working group; and additional industry representatives. This article summarizes the discussions that occurred at the meeting of the state of the Safety of Atrial Fibrillation Ablation Registry Initiative, the identification of a clear pathway for its implementation, and the exploration of solutions to potential issues in the execution of this registry. Copyright © 2010 Mosby, Inc. All rights reserved.

Navigating the fine line between benefit and risk in chronic atrial fibrillation: rationale and design of the Standard versus Atrial Fibrillation spEcific managemenT studY (SAFETY).

PubMed

Carrington, Melinda J; Ball, Jocasta; Horowitz, John D; Marwick, Thomas H; Mahadevan, Gnanadevan; Wong, Chiew; Abhayaratna, Walter P; Haluska, Brian; Thompson, David R; Scuffham, Paul A; Stewart, Simon

2013-06-20

Health outcomes associated with atrial fibrillation (AF) continue to be poor and standard management often does not provide clinical stability. The Standard versus Atrial Fibrillation spEcific managemenT studY (SAFETY) compares the efficacy of a post-discharge, nurse-led, multi-disciplinary programme to optimise AF management with usual care. SAFETY is a prospective, multi-centre, randomised controlled trial with blinded-endpoint adjudication. A target of 320 hospitalised patients with a chronic form of AF will be randomised (stratified by "rate" versus "rhythm" control) to usual post-discharge care or the SAFETY Intervention (SI). The SI involves home-based assessment, extensive clinical profiling and the application of optimal gold-standard pharmacology which is individually tailored according to a "traffic light" framework based on clinical stability, risk profile and therapeutic management. The primary endpoint is event-free survival from all-cause death or unplanned readmission during 18-36 months follow-up. Secondary endpoints include rate of recurrent hospital stay, treatment success (i.e. maintenance of rhythm or rate control and/or application of anti-thrombotic therapy without a bleeding event) and cost-efficacy. With study recruitment to be completed in early 2012, the results of this study will be available in early 2014. If positive, SAFETY will represent a potentially cost-effective and readily applicable strategy to improve health outcomes in high risk individuals discharged from hospital with chronic AF. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Atrial fibrillation and stroke: the evolving role of rhythm control.

PubMed

Patel, Taral K; Passman, Rod S

2013-06-01

Atrial fibrillation (AF) remains a major risk factor for stroke. Unfortunately, clinical trials have failed to demonstrate that a strategy of rhythm control--therapy to maintain normal sinus rhythm (NSR)--reduces stroke risk. The apparent lack of benefit of rhythm control likely reflects the difficulty in maintaining NSR using currently available therapies. However, there are signals from several trials that the presence of NSR is indeed beneficial and associated with better outcomes related to stroke and mortality. Most electrophysiologists feel that as rhythm control strategies continue to improve, the crucial link between rhythm control and stroke reduction will finally be demonstrated. Therefore, AF specialists tend to be aggressive in their attempts to maintain NSR, especially in patients who have symptomatic AF. A step-wise approach from antiarrhythmic drugs to catheter ablation to cardiac surgery is generally used. In select patients, catheter ablation or cardiac surgery may supersede antiarrhythmic drugs. The choice depends on the type of AF, concurrent heart disease, drug toxicity profiles, procedural risks, and patient preferences. Regardless of strategy, given the limited effectiveness of currently available rhythm control therapies, oral anticoagulation is still recommended for stroke prophylaxis in AF patients with other stroke risk factors. Major challenges in atrial fibrillation management include selecting patients most likely to benefit from rhythm control, choosing specific antiarrhythmic drugs or procedures to achieve rhythm control, long-term monitoring to gauge the efficacy of rhythm control, and determining which (if any) patients may safely discontinue anticoagulation if long-term NSR is achieved.

Members of the emergency medical team may have difficulty diagnosing rapid atrial fibrillation in Wolff-Parkinson-White syndrome.

PubMed

Koźluk, Edward; Timler, Dariusz; Zyśko, Dorota; Piątkowska, Agnieszka; Grzebieniak, Tomasz; Gajek, Jacek; Gałązkowski, Robert; Fedorowski, Artur

2015-01-01

Atrial fibrillation (AF) in patients with Wolff-Parkinson-White (WPW) syndrome is potentially life-threatening as it may deteriorate into ventricular fibrillation. The aim of this study was to assess whether the emergency medical team members are able to diagnose AF with a rapid ventricular response due to the presence of atrioventricular bypass tract in WPW syndrome. The study group consisted of 316 participants attending a national congress of emergency medicine. A total of 196 questionnaires regarding recognition and management of cardiac arrhythmias were distributed. The assessed part presented a clinical scenario with a young hemodynamically stable man who had a 12-lead electrocardiogram performed in the past with signs of pre-excitation, and who presented to the emergency team with an irregular broad QRS-complex tachycardia. A total of 71 questionnaires were filled in. Only one responder recognized AF due to WPW syndrome, while 5 other responders recognized WPW syndrome and paroxysmal supraventricular tachycardia or broad QRS-complex tachycardia. About 20% of participants did not select any diagnosis, pointing out a method of treatment only. The most common diagnosis found in the survey was ventricular tachycardia/broad QRS-complex tachycardia marked by approximately a half of the participants. Nearly 18% of participants recognized WPW syndrome, whereas AF was recognized by less than 10% of participants. Members of emergency medical teams have limited skills for recognizing WPW syndrome with rapid AF, and ventricular tachycardia is the most frequent incorrect diagnosis.

The prevalence of oral anticoagulation in patients with atrial fibrillation in Portugal: Systematic review and meta-analysis of observational studies.

PubMed

Caldeira, Daniel; Barra, Márcio; David, Cláudio; Costa, João; Ferreira, Joaquim J; Pinto, Fausto J

2014-09-01

Oral anticoagulation (OAC) is an effective treatment in the prevention of thromboembolic events in patients with atrial fibrillation (AF). The aim of this review was to estimate the prevalence of OAC therapy in patients with AF in Portugal. MEDLINE, the Index of Portuguese Medical Journals and SIBUL (the Bibliographic Catalog of the Integrated Library System of the University of Lisbon) were searched for Portuguese observational studies reporting the proportion of anticoagulated patients with AF. The pooled estimated prevalence of anticoagulated patients and respective 95% confidence interval (CI) were determined by means of a meta-analysis. Seven studies were included for analysis, of which four were conducted in a hospital environment and three in the general community. These studies enrolled a total of 891 patients with AF. The pooled estimated prevalence of anticoagulated patients was 40% (95% CI: 32-48%). The prevalence of OAC in Portuguese AF patients is low. There is a need to promote change in OAC prescribing habits for AF patients in Portugal, in accordance with international guidelines. Copyright © 2014 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

Model-based dose selection for phase III rivaroxaban study in Japanese patients with non-valvular atrial fibrillation.

PubMed

Tanigawa, Takahiko; Kaneko, Masato; Hashizume, Kensei; Kajikawa, Mariko; Ueda, Hitoshi; Tajiri, Masahiro; Paolini, John F; Mueck, Wolfgang

2013-01-01

The global ROCKET AF phase III trial evaluated rivaroxaban 20 mg once daily (o.d.) for stroke prevention in atrial fibrillation (AF). Based on rivaroxaban pharmacokinetics in Japanese subjects and lower anticoagulation preferences in Japan, particularly in elderly patients, the optimal dose regimen for Japanese AF patients was considered. The aim of this analysis was dose selection for Japanese patients from a pharmacokinetic aspect by comparison of simulated exposure in Japanese patients with those in Caucasian patients. As a result of population pharmacokinetics-pharmacodynamics analyses, a one-compartment pharmacokinetic model with first-order absorption and direct link pharmacokinetic-pharmacodynamic models optimally described the plasma concentration and pharmacodynamic models (Factor Xa activity, prothrombin time, activated partial thromboplastin time, and HepTest), which were also consistent with previous works. Steady-state simulations indicated 15 mg rivaroxaban o.d. doses in Japanese patients with AF would yield exposures comparable to the 20 mg o.d. dose in Caucasian patients with AF. In conclusion, in the context of the lower anticoagulation targets in Japanese practice, the population pharmacokinetic and pharmacodynamic modeling supports 15 mg o.d. as the principal rivaroxaban dose in J-ROCKET AF.

Atrial fibrillation: effects beyond the atrium?

PubMed

Wijesurendra, Rohan S; Casadei, Barbara

2015-03-01

Atrial fibrillation (AF) is the most common sustained clinical arrhythmia and is associated with significant morbidity, mostly secondary to heart failure and stroke, and an estimated two-fold increase in premature death. Efforts to increase our understanding of AF and its complications have focused on unravelling the mechanisms of electrical and structural remodelling of the atrial myocardium. Yet, it is increasingly recognized that AF is more than an atrial disease, being associated with systemic inflammation, endothelial dysfunction, and adverse effects on the structure and function of the left ventricular myocardium that may be prognostically important. Here, we review the molecular and in vivo evidence that underpins current knowledge regarding the effects of human or experimental AF on the ventricular myocardium. Potential mechanisms are explored including diffuse ventricular fibrosis, focal myocardial scarring, and impaired myocardial perfusion and perfusion reserve. The complex relationship between AF, systemic inflammation, as well as endothelial/microvascular dysfunction and the effects of AF on ventricular calcium handling and oxidative stress are also addressed. Finally, consideration is given to the clinical implications of these observations and concepts, with particular reference to rate vs. rhythm control. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Cardiology.

Recent advances in rhythm control for atrial fibrillation

PubMed Central

Bond, Richard; Olshansky, Brian; Kirchhof, Paulus

2017-01-01

Atrial fibrillation (AF) remains a difficult management problem. The restoration and maintenance of sinus rhythm—rhythm control therapy—can markedly improve symptoms and haemodynamics for patients who have paroxysmal or persistent AF, but some patients fare well with rate control alone. Sinus rhythm can be achieved with anti-arrhythmic drugs or electrical cardioversion, but the maintenance of sinus rhythm without recurrence is more challenging. Catheter ablation of the AF triggers is more effective than anti-arrhythmic drugs at maintaining sinus rhythm. Whilst pulmonary vein isolation is an effective strategy, other ablation targets are being evaluated to improve sinus rhythm maintenance, especially in patients with chronic forms of AF. Previously extensive ablation strategies have been used for patients with persistent AF, but a recent trial has shown that pulmonary vein isolation without additional ablation lesions is associated with outcomes similar to those of more extensive ablation. This has led to an increase in catheter-based technology to achieve durable pulmonary vein isolation. Furthermore, a combination of anti-arrhythmic drugs and catheter ablation seems useful to improve the effectiveness of rhythm control therapy. Two large ongoing trials evaluate whether a modern rhythm control therapy can improve prognosis in patients with AF. PMID:29043080

Wenxin Keli for atrial fibrillation

PubMed Central

He, Zhuogen; Zheng, Minan; Xie, Pingchang; Wang, Yuanping; Yan, Xia; Deng, Dingwei

2018-01-01

Abstract Background: Atrial fibrillation (AF) is a most common cardiac arrhythmia in clinical practice. In China, Wenxin Keli (WXKL) therapy is a common treatment for AF, but its effects and safety remain uncertain. This protocol is to provide the methods used to assess the effectiveness and safety of WXKL for the treatment of patients with AF. Methods: We will search comprehensively the 4 English databases EMBASE, the Cochrane Central Register of Controlled Trials (Cochrane Library), PubMed, and Medline and 3 Chinese databases China National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature Database (CBM), and Chinese Science and Technology Periodical database (VIP) on computer on March 2018 for the randomized controlled trials (RCTs) regarding WXKL for AF. The therapeutic effects according to the sinus rhythm and p-wave dispersion (Pwd) will be accepted as the primary outcomes. We will use RevMan V.5.3 software as well to compute the data synthesis carefully when a meta-analysis is allowed. Results: This study will provide a high-quality synthesis of current evidence of WXKL for AF. Conclusion: The conclusion of our systematic review will provide evidence to judge whether WXKL is an effective intervention for patient with AF. PROSPERO registration number: PROSPERO CRD 42018082045. PMID:29702984

Atrial fibrillation and arterial hypertension: A common duet with dangerous consequences where the renin angiotensin-aldosterone system plays an important role.

PubMed

Seccia, Teresa Maria; Caroccia, Brasilina; Muiesan, Maria Lorenza; Rossi, Gian Paolo

2016-03-01

Atrial fibrillation (AF) represents the most common sustained cardiac arrhythmia, as it affects 1%-2% of the general population and up to 15% of people over 80 years. High blood pressure, due to its high prevalence in the general population, is by far the most common condition associated with AF, although a variety of diseases, including valvular, coronary heart and metabolic diseases, are held to create the substrate favouring AF. Due to the concomitance of these conditions, it is quite challenging to dissect the precise role of high blood pressure in triggering/causing AF. Hence, even though the intimate association between high blood pressure and AF has been known for decades, the underlying mechanisms remain partially unknown. Accumulating evidences point to a major role of the renin-angiotensin-aldosterone system in inducing cardiac inflammation and fibrosis, and therefore electric and structural atrial and ventricular remodelling, with changes in ions and cell junctions leading to AF development. These evidences are herein reviewed with a particular emphasis to the role of the renin-angiotensin-system aldosterone system. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Preoperative atrial fibrillation and long-term survival after open heart surgery in a rural tertiary heart institute.

PubMed

O'Neal, Wesley T; Efird, Jimmy T; Davies, Stephen W; Choi, Yuk Ming; Anderson, Curtis A; Kindell, Linda C; O'Neal, Jason B; Ferguson, T Bruce; Chitwood, W Randolph; Kypson, Alan P

2013-01-01

Preoperative atrial fibrillation (AF) is associated with increased morbidity and mortality after open heart surgery. However, the impact of preoperative AF on long-term survival after open heart surgery has not been widely examined in rural populations. Patients from rural regions are less likely to receive treatment for cardiac conditions and to have adequate medical insurance coverage. To examine the influence of preoperative AF on long-term survival following open heart surgery in rural eastern North Carolina. Long-term survival was compared in patients with and without preoperative AF after coronary artery bypass grafting (CABG) and CABG plus valve (CABG + V) surgery between 2002 and 2011. Hazard ratios (HR) and 95% confidence intervals (CI) were computed using a Cox regression model. The study population consisted of 5438 patients. A total of 263 (5%) patients had preoperative AF. Preoperative AF was an independent predictor of long-term survival (open heart surgery: adjusted HR = 1.6, 95% CI = 1.3-2.0; CABG: adjusted HR = 1.6, 95% CI = 1.3-2.1; CABG + V: adjusted HR = 1.6, 95% CI = 1.1-2.3). Preoperative AF is an important predictor of long-term survival after open heart surgery in this rural population. Copyright © 2013 Elsevier Inc. All rights reserved.

Atrial fibrillation in transcatheter aortic valve implantation patients: Incidence, outcome and predictors of new onset.

PubMed

Zweiker, David; Fröschl, Mario; Tiede, Stephanie; Weidinger, Paul; Schmid, Johannes; Manninger, Martin; Brussee, Helmut; Zweiker, Robert; Binder, Josepha; Mächler, Heinrich; Marte, Wolfgang; Maier, Robert; Luha, Olev; Schmidt, Albrecht; Scherr, Daniel

There is controversial evidence if atrial fibrillation (AF) alters outcome after transcatheter aortic valve implantation (TAVI). TAVI itself may promote new-onset AF (NOAF). We performed a single-center study including 398 consecutive patients undergoing TAVI. Before TAVI, patients were divided into a sinus rhythm (SR) group (n=226, 57%) and baseline AF group (n=172, 43%) according to clinical records and electrocardiograms. Furthermore, incidence and predictors of NOAF were recorded. Baseline AF patients had a significantly higher 1-year mortality than the baseline SR group (19.8% vs. 11.5%, p=0.02). NOAF occurred in 7.1% of patients with prior SR. Previous valve surgery was the only significant predictor of NOAF (HR 5.86 [1.04-32.94], p<0.05). NOAF was associated with higher rehospitalization rate (62.5 vs. 34.8%, p=0.04), whereas mortality was unaffected. This study shows that NOAF is associated with higher rates of rehospitalization but not mortality after TAVI. Overall, patients with pre-existing AF have higher mortality. Copyright © 2017 Elsevier Inc. All rights reserved.

Association of warfarin with congestive heart failure and peripheral artery occlusive disease in hemodialysis patients with atrial fibrillation.

PubMed

Lee, Kuo-Hua; Li, Szu-Yuan; Liu, Jin-Sin; Huang, Chi-Ting; Chen, Ying-Ying; Lin, Yao-Ping; Hsu, Chih-Cheng; Tarng, Der-Cherng

2017-05-01

The effect of warfarin on the risk of cardiovascular (CV) disease is unknown among chronic hemodialysis patients with atrial fibrillation (HD-AF). Population-based propensity score and prescription time-distribution matched cohort study including 6719 HD-AF patients with CHA 2 DS 2 -VASc score ≥ 2 were divided into warfarin users and nonusers and followed-up for CV events and death. Warfarin treatment in HD-AF patients with AF preceding HD was associated with higher risks of developing congestive heart failure [hazard ratio (HR)=1.82, 95% confidence interval (CI)=1.29-2.58, p<0.01], peripheral artery occlusive disease (HR=3.42, 95% CI=1.86-6.31, p<0.01), and aortic valve stenosis (HR=3.20, 95% CI=1.02-9.98, p<0.05). Warfarin users were not associated with risks of ischemic or hemorrhagic stroke and all-cause mortality as compared to nonusers. Warfarin may be associated with vascular calcification, increasing the risks of congestive heart failure and peripheral artery occlusive disease among HD-AF patients. Copyright © 2017. Published by Elsevier Taiwan LLC.

Usefulness of HATCH score as a predictor of atrial fibrillation after coronary artery bypass graft.

PubMed

Emren, Volkan; Aldemir, Mustafa; Duygu, Hamza; Kocabaş, Uğur; Tecer, Evren; Cerit, Levent; Erdil, Nevzat

2016-01-01

Atrial fibrillation (AF) after coronary artery bypass graft (CABG) surgery is associated with increased morbidity and mortality. The HATCH score was originally devised to predict the progression of paroxysmal AF to persistent AF. To determine whether the HATCH score predicts the development of AF after CABG surgery. The medical records of 284 consecutive patients, who underwent CABG surgery between January 2013 and December 2014, were retrospectively reviewed for the development of AF in the postoperative (POAF) period. The HATCH score, and clinical and echocardiographic parameters were evaluated for all patients. Seventy (25%) patients developed POAF. The HATCH scores were higher in the POAF group (2.8 ± 1.8 vs. 1.1 ± 1.2, p < 0.001). The area of the HATCH score under the curve in the receiver operating characteristics analysis was 773 (95% CI 706-841, p < 0.001). When the HATCH score was 2 or more as a threshold, there was for POAF 72% sensitivity and 75% specificity. The results of the present study suggest that the HATCH score can be used to predict the development of POAF.

Application of Traditional Chinese Medicine in Treatment of Atrial Fibrillation

PubMed Central

Dong, Yan; Yao, Kuiwu; Jiang, Wenrui

2017-01-01

Atrial fibrillation (AF) is the most common cardiac arrhythmia, which is related to many cardiac and cerebral vascular diseases, especially stroke. It can therefore increase cardiovascular mortality and all-cause death. The current treatments of AF remain to be western drugs and radiofrequency ablation which are limited by the tolerance of patients, adverse side effects, and high recurrence rate, especially for the elderly. On the contrary, traditional Chinese medicine (TCM) with long history of use involves various treatment methods, including Chinese herbal medicines (CHMs) or bioactive ingredients, Chinese patent medicines, acupuncture, Qigong, and Tai Chi Chuan. With more and more researches reported, the active roles of TCM in AF management have been discovered. Then it is likely that TCM would be effective preventive means and valuable additional remedy for AF. The potential mechanisms further found by numerous experimental studies showed the distinct characteristics of TCM. Some CHMs or bioactive ingredients are atrial-selective, while others are multichannel and multifunctional. Therefore, in this review we summarized the treatment strategies reported in TCM, with the purpose of providing novel ideas and directions for AF management. PMID:28243308

Biomarkers of Inflammation, Thrombogenesis, and Collagen Turnover in Patients With Atrial Fibrillation.

PubMed

Jabati, Sallu; Fareed, Jawed; Liles, Jeffrey; Otto, Abigail; Hoppensteadt, Debra; Bontekoe, Jack; Phan, Trung; Walborn, Amanda; Syed, Mushabbar

2018-07-01

The purpose of this study was to determine whether there are any differences in the levels of inflammatory, thrombotic, and collagen turnover biomarkers between individuals with atrial fibrillation (AF) and healthy volunteers. Circulating plasma levels of plasminogen activator inhibitor 1 (PAI-1), CD40-ligand (CD40-L), nucleosomes (which are indicators of cell death), C-reactive protein (CRP), procollagen III N-terminal propeptide (PIIINP), procollagen III C-terminal propeptide (PIIICP), procollagen I N-terminal propeptide, tissue plasminogen activator, and von Willebrand factor were analyzed as potential biomarkers of AF. Baseline plasma was collected from patients with AF prior to ablation surgery at Loyola University Medical Center. Individuals with AF had statistically significantly increased levels of PAI-1, CD40-L, and nucleosomes, when compared to the normal population ( P < .0001). Additionally, there was a statistically significant increase in the CRP ( P = .01), PIIINP ( P = .04), and PIIICP ( P = .0008) when compared to normal individuals. From this study, it is concluded that the prothrombotic, inflammatory, and collagen turnover biomarkers PAI-1, CD40-L, nucleosomes, CRP, PIIICP, and PIIINP are elevated in AF.

Comparison of costs and discharge outcomes for patients hospitalized for ischemic or hemorrhagic stroke with or without atrial fibrillation in the United States.

PubMed

Pan, Xianying; Simon, Teresa A; Hamilton, Melissa; Kuznik, Andreas

2015-05-01

This retrospective analysis investigated the impact of baseline clinical characteristics, including atrial fibrillation (AF), on hospital discharge status (to home or continuing care), mortality, length of hospital stay, and treatment costs in patients hospitalized for stroke. The analysis included adult patients hospitalized with a primary diagnosis of ischemic or hemorrhagic stroke between January 2006 and June 2011 from the premier alliance database, a large nationally representative database of inpatient health records. Patients included in the analysis were categorized as with or without AF, based on the presence or absence of a secondary listed diagnosis of AF. Irrespective of stroke type (ischemic or hemorrhagic), AF was associated with an increased risk of mortality during the index hospitalization event, as well as a higher probability of discharge to a continuing care facility, longer duration of stay, and higher treatment costs. In patients hospitalized for a stroke event, AF appears to be an independent risk factor of in-hospital mortality, discharge to continuing care, length of hospital stay, and increased treatment costs.

Left lateral decubitus position on patients with atrial fibrillation and congestive heart failure

NASA Astrophysics Data System (ADS)

Varadan, Vijay K.; Kumar, Prashanth S.; Ramasamy, Mouli

2017-04-01

Congestive Heart Failure (CHF) is a cardiovascular disease that affects about 5.7 million people in the US. The most prevalent comorbidity to CHF is Atrial Fibrillation (AF). These two pathologies present in a mutually worsening manner in that patients diagnosed with CHF are more likely to develop AF and patients who are diagnosed with AF are more likely to develop CHF. The underlying pathophysiological mechanisms have been studied for several years and the most recent efforts are in the cellular and molecular basis. In this paper, we focus on manifestation of CHF and AF symptoms as influenced by the posture assumed by a patient. We consider three postures - Left lateral decubitus, right lateral decubitus and supine. We review the clinical evidence gathered thus far relating enhanced sympathetic activity to the left lateral decubitus and supine positions with equivalent evidence on the enhanced vagal activity when the right lateral decubitus posture is assumed. We conclude with a compilation of all the hypotheses on the mechanism by which the right lateral decubitus posture alleviates the symptoms of CHF and AF, and future avenues for investigation.

iPhone ECG screening by practice nurses and receptionists for atrial fibrillation in general practice: the GP-SEARCH qualitative pilot study.

PubMed

Orchard, Jessica; Freedman, Saul Benedict; Lowres, Nicole; Peiris, David; Neubeck, Lis

2014-05-01

Atrial fibrillation (AF) is often asymptomatic and substantially increases stroke risk. A single-lead iPhone electrocardiograph (iECG) with a validated AF algorithm could make systematic AF screening feasible in general practice. A qualitative screening pilot study was conducted in three practices. Receptionists and practice nurses screened patients aged ≥65 years using an iECG (transmitted to a secure website) and general practitioner (GP) review was then provided during the patient's consultation. Fourteen semi-structured interviews with GPs, nurses, receptionists and patients were audio-recorded, transcribed and analysed thematically. Eighty-eight patients (51% male; mean age 74.8 ± 8.8 years) were screened: 17 patients (19%) were in AF (all previously diagnosed). The iECG was well accepted by GPs, nurses and patients. Receptionists were reluctant, whereas nurses were confident in using the device, explaining and providing screening. AF screening in general practice is feasible. A promising model is likely to be one delivered by a practice nurse, but depends on relevant contextual factors for each practice.

Ethnic distribution of ECG predictors of atrial fibrillation and its impact on understanding the ethnic distribution of ischemic stroke in the Atherosclerosis Risk in Communities (ARIC) study.

PubMed

Soliman, Elsayed Z; Prineas, Ronald J; Case, L Douglas; Zhang, Zhu-ming; Goff, David C

2009-04-01

The paradox of the reported low prevalence of atrial fibrillation (AF) in blacks compared with whites despite higher stroke rates in the former could be related to limitations in the current methods used to diagnose AF in population-based studies. Hence, this study aimed to use the ethnic distribution of ECG predictors of AF as measures of AF propensity in different ethnic groups. The distribution of baseline measures of P-wave terminal force, P-wave duration, P-wave area, and PR duration (referred to as AF predictors) were compared by ethnicity in 15 429 participants (27% black) from the Atherosclerosis Risk in Communities (ARIC) study by unpaired t test, chi(2), and logistic-regression analysis, as appropriate. Cox proportional-hazards analysis was used to separately examine the association of AF predictors with incident AF and ischemic stroke. Whereas AF was significantly less common in blacks compared with whites (0.24% vs 0.95%, P<0.0001), similar to what has been reported in previous studies, blacks had significantly higher and more abnormal values of AF predictors (P<0.0001 for all comparisons). Black ethnicity was significantly associated with abnormal AF predictors compared with whites; odds ratios for different AF predictors ranged from 2.1 to 3.1. AF predictors were significantly and independently associated with AF and ischemic stroke with no significant interaction between ethnicity and AF predictors, findings that further justify using AF predictors as an earlier indicator of future risk of AF and stroke. There is a disconnect between the ethnic distribution of AF predictors and the ethnic distribution of AF, probably because the former, unlike the latter, do not suffer from low sensitivity. These results raise the possibility that blacks might actually have a higher prevalence of AF that might have been missed by previous studies owing to limited methodology, a difference that could partially explain the greater stroke risk in blacks.

Diagnostic Yield of Extended Cardiac Patch Monitoring in Patients with Stroke or TIA.

PubMed

Tung, Christie E; Su, Derek; Turakhia, Mintu P; Lansberg, Maarten G

2014-01-01

It is important to evaluate patients with transient ischemic attack (TIA) or stroke for atrial fibrillation (AF) because the detection of AF changes the recommended anti-thrombotic regimen from treatment with an antiplatelet agent to oral anticoagulation. This study describes the diagnostic yield of a patch-based, single-use, and water-resistant 14-day continuous cardiac rhythm monitor (ZIO Patch) in patients with stroke or TIA. We obtained data from the manufacturer and servicer of the ZIO Patch (iRhythm Technologies). Patients who were monitored between January 2012 and June 2013 and whose indication for monitoring was TIA or stroke were included. The duration of monitoring, the number and type of arrhythmias, and the time to first arrhythmia were documented. One thousand one hundred seventy-one monitoring reports were analyzed. The mean monitor wear time was 10.9 days and the median wear time was 13.0 days (interquartile range 7.2-14.0). The median analyzable time relative to the total wear time was 98.7% (IQR 96.0-99.5%). AF was present in 5.0% of all reports. The mean duration before the first episode of paroxysmal AF (PAF) was 1.5 days and the median duration was 0.4 days. 14.3% of first PAF episodes occurred after 48 h. The mean PAF burden was 12.7% of the total monitoring duration. Excellent quality of the recordings and very good patient compliance coupled with a substantial proportion of AF detection beyond the first 48 h of monitoring suggest that the cardiac patch is superior to conventional 48-h Holter monitors for AF detection in patients with stroke or TIA.

The burden of proof: The current state of atrial fibrillation prevention and treatment trials.

PubMed

Zakeri, Rosita; Van Wagoner, David R; Calkins, Hugh; Wong, Tom; Ross, Heather M; Heist, E Kevin; Meyer, Timothy E; Kowey, Peter R; Mentz, Robert J; Cleland, John G; Pitt, Bertram; Zannad, Faiez; Linde, Cecilia

2017-05-01

Atrial fibrillation (AF) is an age-related arrhythmia of enormous socioeconomic significance. In recent years, our understanding of the basic mechanisms that initiate and perpetuate AF has evolved rapidly, catheter ablation of AF has progressed from concept to reality, and recent studies suggest lifestyle modification may help prevent AF recurrence. Emerging developments in genetics, imaging, and informatics also present new opportunities for personalized care. However, considerable challenges remain. These include a paucity of studies examining AF prevention, modest efficacy of existing antiarrhythmic therapies, diverse ablation technologies and practice, and limited evidence to guide management of high-risk patients with multiple comorbidities. Studies examining the long-term effects of AF catheter ablation on morbidity and mortality outcomes are not yet completed. In many ways, further progress in the field is heavily contingent on the feasibility, capacity, and efficiency of clinical trials to incorporate the rapidly evolving knowledge base and to provide substantive evidence for novel AF therapeutic strategies. This review outlines the current state of AF prevention and treatment trials, including the foreseeable challenges, as discussed by a unique forum of clinical trialists, scientists, and regulatory representatives in a session endorsed by the Heart Rhythm Society at the 12th Global CardioVascular Clinical Trialists Forum in Washington, DC, December 3-5, 2015. Copyright © 2017 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

Myocardial architecture and patient variability in clinical patterns of atrial fibrillation

NASA Astrophysics Data System (ADS)

Manani, Kishan A.; Christensen, Kim; Peters, Nicholas S.

2016-10-01

Atrial fibrillation (AF) increases the risk of stroke by a factor of 4-5 and is the most common abnormal heart rhythm. The progression of AF with age, from short self-terminating episodes to persistence, varies between individuals and is poorly understood. An inability to understand and predict variation in AF progression has resulted in less patient-specific therapy. Likewise, it has been a challenge to relate the microstructural features of heart muscle tissue (myocardial architecture) with the emergent temporal clinical patterns of AF. We use a simple model of activation wave-front propagation on an anisotropic structure, mimicking heart muscle tissue, to show how variation in AF behavior arises naturally from microstructural differences between individuals. We show that the stochastic nature of progressive transversal uncoupling of muscle strands (e.g., due to fibrosis or gap junctional remodeling), as occurs with age, results in variability in AF episode onset time, frequency, duration, burden, and progression between individuals. This is consistent with clinical observations. The uncoupling of muscle strands can cause critical architectural patterns in the myocardium. These critical patterns anchor microreentrant wave fronts and thereby trigger AF. It is the number of local critical patterns of uncoupling as opposed to global uncoupling that determines AF progression. This insight may eventually lead to patient-specific therapy when it becomes possible to observe the cellular structure of a patient's heart.

Oxidized Low-density Lipoprotein (ox-LDL) Cholesterol Induces the Expression of miRNA-223 and L-type Calcium Channel Protein in Atrial Fibrillation

PubMed Central

He, Fengping; Xu, Xin; Yuan, Shuguo; Tan, Liangqiu; Gao, Lingjun; Ma, Shaochun; Zhang, Shebin; Ma, Zhanzhong; Jiang, Wei; Liu, Fenglian; Chen, Baofeng; Zhang, Beibei; Pang, Jungang; Huang, Xiuyan; Weng, Jiaqiang

2016-01-01

Atrial fibrillation (AF) is the most common sustained arrhythmia causing high morbidity and mortality. While changing of the cellular calcium homeostasis plays a critical role in AF, the L-type calcium channel α1c protein has suggested as an important regulator of reentrant spiral dynamics and is a major component of AF-related electrical remodeling. Our computational modeling predicted that miRNA-223 may regulate the CACNA1C gene which encodes the cardiac L-type calcium channel α1c subunit. We found that oxidized low-density lipoprotein (ox-LDL) cholesterol significantly up-regulates both the expression of miRNA-223 and L-type calcium channel protein. In contrast, knockdown of miRNA-223 reduced L-type calcium channel protein expression, while genetic knockdown of endogenous miRNA-223 dampened AF vulnerability. Transfection of miRNA-223 by adenovirus-mediated expression enhanced L-type calcium currents and promoted AF in mice while co-injection of a CACNA1C-specific miR-mimic counteracted the effect. Taken together, ox-LDL, as a known factor in AF-associated remodeling, positively regulates miRNA-223 transcription and L-type calcium channel protein expression. Our results implicate a new molecular mechanism for AF in which miRNA-223 can be used as an biomarker of AF rheumatic heart disease. PMID:27488468

Oxidized Low-density Lipoprotein (ox-LDL) Cholesterol Induces the Expression of miRNA-223 and L-type Calcium Channel Protein in Atrial Fibrillation

NASA Astrophysics Data System (ADS)

He, Fengping; Xu, Xin; Yuan, Shuguo; Tan, Liangqiu; Gao, Lingjun; Ma, Shaochun; Zhang, Shebin; Ma, Zhanzhong; Jiang, Wei; Liu, Fenglian; Chen, Baofeng; Zhang, Beibei; Pang, Jungang; Huang, Xiuyan; Weng, Jiaqiang

2016-08-01

Atrial fibrillation (AF) is the most common sustained arrhythmia causing high morbidity and mortality. While changing of the cellular calcium homeostasis plays a critical role in AF, the L-type calcium channel α1c protein has suggested as an important regulator of reentrant spiral dynamics and is a major component of AF-related electrical remodeling. Our computational modeling predicted that miRNA-223 may regulate the CACNA1C gene which encodes the cardiac L-type calcium channel α1c subunit. We found that oxidized low-density lipoprotein (ox-LDL) cholesterol significantly up-regulates both the expression of miRNA-223 and L-type calcium channel protein. In contrast, knockdown of miRNA-223 reduced L-type calcium channel protein expression, while genetic knockdown of endogenous miRNA-223 dampened AF vulnerability. Transfection of miRNA-223 by adenovirus-mediated expression enhanced L-type calcium currents and promoted AF in mice while co-injection of a CACNA1C-specific miR-mimic counteracted the effect. Taken together, ox-LDL, as a known factor in AF-associated remodeling, positively regulates miRNA-223 transcription and L-type calcium channel protein expression. Our results implicate a new molecular mechanism for AF in which miRNA-223 can be used as an biomarker of AF rheumatic heart disease.

10-year nationwide trends of the incidence, prevalence, and adverse outcomes of non-valvular atrial fibrillation nationwide health insurance data covering the entire Korean population.

PubMed

Kim, Daehoon; Yang, Pil-Sung; Jang, Eunsun; Yu, Hee Tae; Kim, Tae-Hoon; Uhm, Jae-Sun; Kim, Jong-Youn; Pak, Hui-Nam; Lee, Moon-Hyoung; Joung, Boyoung; Lip, Gregory Yh

2018-05-01

Most data on the clinical epidemiology of atrial fibrillation (AF) are reported from Western populations, and data for Asians are limited. We aimed to investigate the 10-year trends of the prevalence and incidence of non-valvular AF and provide prevalence projections till 2060 in Korea. We also investigated the annual risks of adverse outcomes among patients with AF. Using the Korean National Health Insurance Service database involving the entire Korean population, a total of 679,416 adults with newly diagnosed AF were identified from 2006 to 2015. The incidence and prevalence of AF and risk of adverse outcomes following AF onset were assessed. The prevalence of AF progressively increased by 2.10-fold from 0.73% in 2006 to 1.53% in 2015. The trend of its incidence was flat with a 10-year overall incidence of 1.77 per 1,000 person-years. The prevalence of AF is expected to reach 5.81% (2,290,591 patients with AF) in 2060. For a decade, the risk of all-cause mortality following AF declined by 30% (adjusted hazard ratio [HR]: 0.70, 95% confidence interval [CI]: 0.68-0.72), heart failure by 52% (adjusted HR: 0.48, 95% CI: 0.44-0.51), and ischemic stroke by 9% (adjusted HR: 0.91, 95% CI: 0.88-0.93). The burden of AF among Asian patients is increasing. Although the overall risks of cardiovascular events and death following AF onset have decreased over a decade, the event rates are still high. Optimized management of any associated comorbidities should be part of the holistic management approach for patients with AF. Copyright © 2018. Published by Elsevier Inc.

An epidemiological study on the prevalence of atrial fibrillation in the Chinese population of mainland China.

PubMed

Zhou, Ziqiang; Hu, Dayi

2008-01-01

Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice. Since only limited data on the Chinese population, which is the largest in the world, is available, we conducted an epidemiological study on the prevalence and risk factors of AF in mainland China. This population-based study conducted by cluster sampling comprised 29079 participants forming 14 cohorts from 13 provinces across China, where the population was nearly 1 billion. Every participant underwent electrocardiogram and physical examinations and responded to the interviewer-led questionnaire(s). Univariate and multiple statistical analyses were conducted to explore the relationship between AF prevalence and risk factors. The age-standardized prevalence of AF in China (>or=30 y) was 0.65%, and it increased with age. Men showed a higher prevalence of AF than women (0.91% [age-standardized, 0.66%] vs. 0.65% [0.63%], P = 0.013); several significant risk factors (age, hyperthyroidism, coronary heart disease, and rheumatic heart disease) were identified for AF in the general population. Stroke prevalence was much higher in AF patients than in non-AF people (12.95% vs. 2.28%, P < 0.001). AF was confirmed to be a significant independent risk factor for stroke prevalence in the studied population (OR = 2.776, [1.814, 4.248], P < 0.001). We found that AF patients received poor treatment (2.7%, warfarin; 39.7%, aspirin). This study conducted on a large sample size demonstrates that AF prevalence in mainland China is slightly lower than that in Western countries and similar to that in Asian areas, and confirms that AF is a serious public health problem in China. We identified several potential risk factors, but their associations with AF still need to be further studied.

Predictors of Long-term Success After Concomitant Surgical Ablation for Atrial Fibrillation.

PubMed

Pecha, Simon; Ghandili, Susanne; Hakmi, Samer; Willems, Stephan; Reichenspurner, Hermann; Wagner, Florian Mathias

2017-01-01

According to guidelines, atrial fibrillation (AF) ablation success should be measured by 24-hour Holter electrocardiogram (ECG). However, information on long-term success, especially obtained by 24-hour Holter ECG, is rare. We therefore analyzed rhythm course and long-term outcomes of our patients undergoing concomitant surgical AF ablation. Between January 2003 and April 2011, 486 patients underwent concomitant surgical AF ablation in our institution. Patients with 24-hour Holter ECG rhythm status available between 5 and 10 years postoperatively were included in this retrospective data analysis (n = 155). Ablation lesions were limited to either a pulmonary vein isolation (n = 31, 20%), a more complex left atrial lesion set (n = 89, 57%), or biatrial lesions (n = 35, 23%). Primary end point of the study was freedom from AF during long-term follow-up. Mean patient age was 68.1 ± 8.4 years; 57.4% were male. Mean follow-up time was 5.9 years. Surgical AF ablation provided freedom from AF rate of 56.6% during long-term follow-up, with significantly better results in patients with paroxysmal than in those with persistent AF (67.2% vs 51.8% P = 0.03). A stable rhythm course was observed during follow-up, without statistically significant differences between 12 months and latest follow-up (63.2% vs 56.6%; P = 0.25). In multivariate analysis, preoperative paroxysmal AF, duration of AF, and left atrial diameter were predictors of long-term ablation success. Surgical AF ablation provided freedom from AF rate of 56.6% during long-term follow-up. Statistically significant predictors of ablation success at latest follow-up were preoperative paroxysmal AF, duration of AF, and a preoperative smaller left atrial diameter. Copyright © 2017. Published by Elsevier Inc.

Comparison of treatment outcomes between convergent procedure and catheter ablation for paroxysmal atrial fibrillation evaluated with implantable loop recorder monitoring.

PubMed

Jan, Matevž; Žižek, David; Geršak, Živa Miriam; Geršak, Borut

2018-05-03

While catheter ablation (CA) is an established treatment for symptomatic paroxysmal atrial fibrillation (AF), convergent epicardial and endocardial ablation procedure (CVP) has been primarily used to treat persistent AF. The aim of this single-center, prospective, randomized study was to compare treatment efficacy of CA and CVP in paroxysmal AF patients by monitoring AF, atrial tachycardia (AT), and atrial flutter (AFL) recurrence with Implantable Loop Recorder (ILR). Fifty patients (74% male) with history of paroxysmal AF were randomized between CA and CVP. Outcomes were determined by ILRs; every episode of AF/AT/AFL lasting 6 minutes or more was defined as a recurrence. AF burden (AFB) and required AF reinterventions (cardioversions and repeat ablations) were quantified after a 3-month blanking period. Total procedural (266 ± 44 vs. 242 ± 39 minutes) and ablation duration (52 ± 10 vs. 48 ± 12 minutes) was similar in both groups. Recurrence of AF/AT/AFL was more likely in the CA group compared to the CVP group (OR 3.78 (95% CI (1.17, 12.19), P  =  0.048)). During the follow-up period (mean 30.5 ± 6.9 months), higher AF burden and more reinterventions for recurrent AF were recorded in the CA group. There were more periprocedural complications in the CVP group (12.5%) compared to the CA group (0%). Treatment of paroxysmal AF with CVP showed less arrhythmia recurrence compared to CA. In addition, patients after CVP had fewer reinterventions and lower AF burden, but more periprocedural complications. © 2018 Wiley Periodicals, Inc.

Atrial Fibrillation and Colonic Neoplasia in African Americans.

PubMed

Nouraie, Mehdi; Kansal, Vandana; Belfonte, Cassius; Ghazvini, Mohammad; Haidari, Tahmineh; Shahnazi, Anahita; Brim, Hassan; Soliman, Elsayed Z; Ashktorab, Hassan

2015-01-01

Colorectal cancer (CRC) and atrial fibrillation/flutter (AF) share several risk factors including increasing age and obesity. However, the association between CRC and AF has not been thoroughly examined, especially in African Americans. In this study we aimed to assess the prevalence of AF and its risk factors in colorectal neoplasia in an African American. We reviewed records of 527 African American patients diagnosed with CRC and 1008 patients diagnosed with benign colonic lesions at Howard University Hospital from January 2000 to December 2012. A control group of 731 hospitalized patients without any cancer or colonic lesion were randomly selected from the same time and age range, excluding patients who had diagnosis of both CRC and/or adenoma. The presence or absence of AF was based upon ICD-9 code documentation. The prevalence of AF in these three groups was compared by multivariate logistic regression. The prevalence of AF was highest among CRC patients (10%) followed by adenoma patients (7.2%) then the control group (5.4%, P for trend = 0.002). In the three groups of participants, older age (P<0.008) and heart failure (P<0.001) were significantly associated with higher risk of AF. After adjusting for these risk factors, CRC (OR: 1.4(95%CI):0.9-2.2, P = 0.2) and adenoma (OR: 1.1(95%CI):0.7-1.6, P = 0.7) were not significantly associated AF compared to control group. AF is highly prevalent among CRC patients; 1 in 10 patients had AF in our study. The predictors of AF in CRC was similar to that in adenoma and other patients after adjustment for potential confounders suggesting that the increased AF risk in CRC is explained by higher prevalence of AF risk factors.

Independent mapping methods reveal rotational activation near pulmonary veins where atrial fibrillation terminates before pulmonary vein isolation.

PubMed

Navara, Rachita; Leef, George; Shenasa, Fatemah; Kowalewski, Christopher; Rogers, Albert J; Meckler, Gabriela; Zaman, Junaid A B; Baykaner, Tina; Park, Shirley; Turakhia, Mintu P; Zei, Paul; Viswanathan, Mohan; Wang, Paul J; Narayan, Sanjiv M

2018-01-29

To investigate mechanisms by which atrial fibrillation (AF) may terminate during ablation near the pulmonary veins before the veins are isolated (PVI). It remains unstudied how AF may terminate during ablation before PVs are isolated, or how patients with PV reconnection can be arrhythmia-free. We studied patients in whom PV antral ablation terminated AF before PVI, using two independent mapping methods. We studied patients with AF referred for ablation, in whom biatrial contact basket electrograms were studied by both an activation/phase mapping method and by a second validated mapping method reported not to create false rotational activity. In 22 patients (age 60.1 ± 10.4, 36% persistent AF), ablation at sites near the PVs terminated AF (77% to sinus rhythm) prior to PVI. AF propagation revealed rotational (n  =  20) and focal (n  =  2) patterns at sites of termination by mapping method 1 and method 2. Both methods showed organized sites that were spatially concordant (P < 0.001) with similar stability (P < 0.001). Vagal slowing was not observed at sites of AF termination. PV antral regions where ablation terminated AF before PVI exhibited rotational and focal activation by two independent mapping methods. These data provide an alternative mechanism for the success of PVI, and may explain AF termination before PVI or lack of arrhythmias despite PV reconnection. Mapping such sites may enable targeted PV lesion sets and improved freedom from AF. © 2018 Wiley Periodicals, Inc.

Atrial Fibrillation Management Strategies in Routine Clinical Practice: Insights from the International RealiseAF Survey

PubMed Central

Chiang, Chern-En; Naditch-Brûlé, Lisa; Brette, Sandrine; Silva-Cardoso, José; Gamra, Habib; Murin, Jan; Zharinov, Oleg J.; Steg, Philippe Gabriel

2016-01-01

Background Atrial fibrillation (AF) can be managed with rhythm- or rate-control strategies. There are few data from routine clinical practice on the frequency with which each strategy is used and their correlates in terms of patients’ clinical characteristics, AF control, and symptom burden. Methods RealiseAF was an international, cross-sectional, observational survey of 11,198 patients with AF. The aim of this analysis was to describe patient profiles and symptoms according to the AF management strategy used. A multivariate logistic regression identified factors associated with AF management strategy at the end of the visit. Results Among 10,497 eligible patients, 53.7% used a rate-control strategy, compared with 34.5% who used a rhythm-control strategy. In 11.8% of patients, no clear strategy was stated. The proportion of patients with AF-related symptoms (EHRA Class > = II) was 78.1% (n = 4396/5630) for those using a rate-control strategy vs. 67.8% for those using a rhythm-control strategy (p<0.001). Multivariate logistic regression analysis revealed that age <75 years or the paroxysmal or persistent form of AF favored the choice of a rhythm-control strategy. A change in strategy was infrequent, even in patients with European Heart Rhythm Association (EHRA) Class > = II. Conclusions In the RealiseAF routine clinical practice survey, rate control was more commonly used than rhythm control, and a change in strategy was uncommon, even in symptomatic patients. In almost 12% of patients, no clear strategy was stated. Physician awareness regarding optimal management strategies for AF may be improved. PMID:26800084

Total and interatrial epicardial adipose tissues are independently associated with left atrial remodeling in patients with atrial fibrillation.

PubMed

Shin, Seung Yong; Yong, Hwan Seok; Lim, Hong Euy; Na, Jin Oh; Choi, Cheol Ung; Choi, Jong Il; Kim, Seong Hwan; Kim, Jin Won; Kim, Eung Ju; Park, Sang Weon; Rha, Seung-Woon; Park, Chang Gyu; Seo, Hong Seog; Oh, Dong Joo; Kim, Young-Hoon

2011-06-01

As epicardial adipose tissue (EAT) is a metabolically active visceral fat, potential interaction between EAT and myocardium is strongly suggested. The aims of this study were to determine whether the amount and regional distribution of EAT are related to the chronicity of atrial fibrillation (AF) and left atrial (LA) remodeling. This study consisted of 40 subjects with paroxysmal AF (PAF) and 40 with persistent AF (PeAF). Eighty subjects with no history of AF were enrolled as controls. Total volume of EAT (EAT(total)), regional thickness of EAT, and LA volume (LAV) were measured by multislice computed tomography. In the AF group, blood samples were drawn from coronary sinus for analysis of inflammatory cytokines including adiponectin. Compared with controls, AF subjects had larger LAV, EAT(total), and the thicknesses of periatrial EAT including interatrial septum (IAS). However, the thicknesses of periventricular EAT were not different between the groups. The PeAF subjects had larger LAV, EAT(total), and periatrial EAT thicknesses, higher levels of inflammatory cytokines, and lower level of adiponectin than did the PAF subjects. Adiponection level was significantly associated with EAT(total) and IAS thickness. Multivariate analysis revealed that EAT(total) (P = 0.004) and IAS thickness (P = 0.016) were independently associated with LAV. EAT(total) and thickness of periatrial EAT were significantly larger in AF subjects compared to those of the matched controls and were closely related to the chronicity of AF. Moreover, EAT(total) and IAS thickness were independently associated with LAV in subjects with AF. © 2011 Wiley Periodicals, Inc.

Mind the model: effect of instrumentation on inducibility of atrial fibrillation in a sheep model.

PubMed

Willems, Rik; Holemans, Patricia; Ector, Hugo; Sipido, Karin R; Van de Werf, Frans; Heidbüchel, Hein

2002-01-01

Atrial electrical remodeling, shortening of the atrial effective refractory period (AERP) underlying atrial fibrillation (AF) has been described in different animal models. However, there remains some controversy regarding the time course of this electrical remodeling and the need for secondary factors in the development of AF. We investigated the effect of instrumentation on the inducibility of AF. We hypothesized that epicardial instrumentation could be a confounding factor that accelerates the development of AF. Thirty sheep were rapidly atrially paced at 600 beats/min for 15 weeks: 15 were endocardially instrumented and paced (endo), and 15 were both endocardially and epicardially instrumented. Six of these animals were endocardially paced (sham) and 9 were epicardially paced (epi). The underlying rhythm was determined at regular intervals, and electrophysiologic study was performed. AF developed significantly faster in the epi group. After 3 weeks of pacing, the cumulative incidence of sustained AF (>1 hour) already was 70% in this group versus only 14% and 20% in the endo and sham groups, respectively. After 15 weeks of pacing, this difference was no longer evident. Baseline AERP and minimal AERP, reached before the development of AF, were not significantly different in the three groups. Epicardial instrumentation (epi and sham) increased baseline left and right atrial pressures, but only epicardial stimulation (epi) led to early development of AF. In this sheep model of AF, the experimental setup is a major determinant of the inducibility of AF. Not epicardial instrumentation per se but epicardial stimulation accelerated the development of AF. Different animal models

The Role of the Atrial Electromechanical Delay in Predicting Atrial Fibrillation in Myotonic Dystrophy Type 1 Patients.

PubMed

Russo, Vincenzo; Rago, Anna; Ciardiello, Carmine; Russo, Maria Giovanna; Calabrò, Paolo; Politano, Luisa; Nigro, Gerardo

2016-01-01

Paroxysmal atrial tachyarrhythmias frequently occur in myotonic dystrophy type 1 (DM1) patients. The aim of the current study was to evaluate the atrial electromechanical-delay (AEMD) in a DM1-population with normal cardiac function and its relationship to atrial fibrillation (AF) onset. Fifty DM1 patients (28 male; mean age 34.2 ± 11.4 years) and 50 healthy subjects used as controls, matched for age and gender, were studied for the occurrence of atrial fibrillation during a 4-year follow-up, through 30-day external loop recorder (ELR) monitoring performed every 6 months. Intra-AEMD and inter-AEMD of both atrium were measured through tissue-Doppler echocardiography. Compared to the healthy control group, the DM1 group showed a statistically significant increase in inter-AEMD and intraleft-AEMD. Dividing the DM1-group into 2 subgroups (patients with or without AF), the inter-AEMD and intraleft-AEMD were significantly higher in the subgroup with AF compared to the subgroup without AF. A cut off value of 39.2 milliseconds for intraleft-AEMD had a sensitivity of 90% and a specificity of 90% in identifying DM1 patients with AF risk. A cut off value of 57.7 milliseconds for inter-AEMD had a sensitivity of 84.2% and a specificity of 93.5% in identifying this category of patients. Our results showed that the echocardiographic atrial electromechanical delay indices (intraleft and inter-AEMD) were significantly increased in DM1 subjects with normal cardiac function. Intraleft and inter-AEMD represent noninvasive, inexpensive, useful and simple parameters to assess the AF risk in DM1 patients. © 2015 Wiley Periodicals, Inc.

Variations in cause and management of atrial fibrillation in a prospective registry of 15,400 emergency department patients in 46 countries: the RE-LY Atrial Fibrillation Registry.

PubMed

Oldgren, Jonas; Healey, Jeff S; Ezekowitz, Michael; Commerford, Patrick; Avezum, Alvaro; Pais, Prem; Zhu, Jun; Jansky, Petr; Sigamani, Alben; Morillo, Carlos A; Liu, Lisheng; Damasceno, Albertino; Grinvalds, Alex; Nakamya, Juliet; Reilly, Paul A; Keltai, Katalin; Van Gelder, Isabelle C; Yusufali, Afzal Hussein; Watanabe, Eiichi; Wallentin, Lars; Connolly, Stuart J; Yusuf, Salim

2014-04-15

Atrial fibrillation (AF) is the most common sustained arrhythmia; however, little is known about patients in a primary care setting from high-, middle-, and low-income countries. This prospective registry enrolled patients presenting to an emergency department with AF at 164 sites in 46 countries representing all inhabited continents. Patient characteristics were compared among 9 major geographic regions. Between September 2008 and April 2011, 15,400 patients were enrolled. The average age was 65.9, standard deviation 14.8 years, ranging from 57.2, standard deviation 18.8 years in Africa, to 70.1, standard deviation 13.4 years in North America, P<0.001. Hypertension was globally the most common risk factor for AF, ranging in prevalence from 41.6% in India to 80.7% in Eastern Europe, P<0.001. Rheumatic heart disease was present in only 2.2% of North American patients, in comparison with 21.5% in Africa and 31.5% in India, P<0.001. The use of oral anticoagulation among patients with a CHADS2 score of ≥2 was greatest in North America (65.7%) but was only 11.2% in China, P<0.001. The mean time in the therapeutic range was 62.4% in Western Europe, 50.9% in North America, but only between 32% and 40% in India, China, Southeast Asia, and Africa, P<0.001. There is a large global variation in age, risk factors, concomitant diseases, and treatment of AF among regions. Improving outcomes globally requires an understanding of this variation and the conduct of research focused on AF associated with different underlying conditions and treatment of AF and predisposing conditions in different socioeconomic settings.

Impact of Proteinuria and Glomerular Filtration Rate on Risk of Thromboembolism in Atrial Fibrillation: the ATRIA Study

PubMed Central

Go, Alan S.; Fang, Margaret C.; Udaltsova, Natalia; Chang, Yuchiao; Pomernacki, Niela K.; Borowsky, Leila; Singer, Daniel E.

2009-01-01

Background Atrial fibrillation (AF) substantially increases the risk of ischemic stroke but this risk varies among individual patients with AF. Existing risk stratification schemes have limited predictive ability. Chronic kidney disease is a major cardiovascular risk factor, but whether it independently increases the risk for ischemic stroke in persons with AF is unknown. Methods and Results We examined how chronic kidney disease (reduced glomerular filtration rate or proteinuria) affects risk of thromboembolism off anticoagulation in patients with AF. We estimated glomerular filtration rate (eGFR) using the Modification of Diet in Renal Disease equation and proteinuria from urine dipstick results found in laboratory databases. Patient characteristics, warfarin use, and thromboembolic events were ascertained from clinical databases, with validation of thromboembolism by chart review. Results During 33,165 person-years off anticoagulation among 10,908 patients with atrial fibrillation, we observed 676 incident thromboembolic events. After adjustment for known risk factors for stroke and other confounders, proteinuria increased the risk of thromboembolism by 54% (relative risk [RR] 1.54, 1.29 to 1.85) and there was a graded, increased risk of stroke associated with progressively lower level of eGFR compared with eGFR ≥60 (in units of ml/min/1.73 m2): RR 1.16 (95% CI: 0.95−1.40) for eGFR 45−59 and RR 1.39 (95% CI: 1.13−1.71) for eGFR <45 (P=0.0082 for trend). Conclusions . Chronic kidney disease increases the risk of thromboembolism in AF independent of other risk factors. Knowing the level of kidney function and presence of proteinuria may improve risk stratification for decision-making about the use of antithrombotic therapy for stroke prevention in AF. PMID:19255343

The AFFORD clinical decision aid to identify emergency department patients with atrial fibrillation at low risk for 30-day adverse events.

PubMed

Barrett, Tyler W; Storrow, Alan B; Jenkins, Cathy A; Abraham, Robert L; Liu, Dandan; Miller, Karen F; Moser, Kelly M; Russ, Stephan; Roden, Dan M; Harrell, Frank E; Darbar, Dawood

2015-03-15

There is wide variation in the management of patients with atrial fibrillation (AF) in the emergency department (ED). We aimed to derive and internally validate the first prospective, ED-based clinical decision aid to identify patients with AF at low risk for 30-day adverse events. We performed a prospective cohort study at a university-affiliated tertiary-care ED. Patients were enrolled from June 9, 2010, to February 28, 2013, and followed for 30 days. We enrolled a convenience sample of patients in ED presenting with symptomatic AF. Candidate predictors were based on ED data available in the first 2 hours. The decision aid was derived using model approximation (preconditioning) followed by strong bootstrap internal validation. We used an ordinal outcome hierarchy defined as the incidence of the most severe adverse event within 30 days of the ED evaluation. Of 497 patients enrolled, stroke and AF-related death occurred in 13 (3%) and 4 (<1%) patients, respectively. The decision aid included the following: age, triage vitals (systolic blood pressure, temperature, respiratory rate, oxygen saturation, supplemental oxygen requirement), medical history (heart failure, home sotalol use, previous percutaneous coronary intervention, electrical cardioversion, cardiac ablation, frequency of AF symptoms), and ED data (2 hours heart rate, chest radiograph results, hemoglobin, creatinine, and brain natriuretic peptide). The decision aid's c-statistic in predicting any 30-day adverse event was 0.7 (95% confidence interval 0.65, 0.76). In conclusion, in patients with AF in the ED, Atrial Fibrillation and Flutter Outcome Risk Determination provides the first evidence-based decision aid for identifying patients who are at low risk for 30-day adverse events and candidates for safe discharge. Copyright © 2015 Elsevier Inc. All rights reserved.

Termination of atrial fibrillation using pulsed low-energy far-field stimulation

PubMed Central

Fenton, Flavio H.; Luther, Stefan; Cherry, Elizabeth M.; Otani, Niels F.; Krinsky, Valentin; Pumir, Alain; Bodenschatz, Eberhard; Gilmour, Robert F.

2010-01-01

Background Electrically-based therapies for terminating atrial fibrillation (AF) currently fall into two categories: anti-tachycardia pacing (ATP) and cardioversion. ATP utilizes low-intensity pacing stimuli delivered via a single electrode and is effective for terminating slower tachycardias, but is less effective for treating AF. In contrast, cardioversion uses a single high-voltage shock to terminate AF reliably, but the voltages required produce undesirable side effects, including tissue damage and pain. We propose a new method to terminate AF called far-field anti-fibrillation pacing (FF-AFP), which delivers a short train of low-intensity electrical pulses at the frequency of ATP, but from field electrodes. Prior theoretical work has suggested that this approach can create a large number of activation sites (“virtual” electrodes) that emit propagating waves within the tissue without implanting physical electrodes and thereby may be more effective than point-source stimulation. Methods and Results Using optical mapping in isolated perfused canine atrial preparations, we show that a series of pulses at low field strength (0.9-1.4 V/cm) is sufficient to entrain and subsequently extinguish AF with a success rate of 93 percent (69/74 trials in 8 preparations). We further demonstrate that the mechanism behind FFAFP success is the generation of wave emission sites within the tissue by the applied electric field, which entrains the tissue as the field is pulsed. Conclusions AF in our model can be terminated by FF-AFP using only 13% of the energy required for cardioversion. Further studies are needed to determine whether this marked reduction in energy can increase the effectiveness and safety of terminating atrial tachyarrhythmias clinically. PMID:19635972

Assessment of anticoagulation treatments in non-valvular atrial fibrillation patients diagnosed in a basic health area.

PubMed

Aguilera Alcaraz, Beatriz M; Abellán Huerta, José; Carbayo Herencia, Julio Antonio; Ariza Copado, Consuelo; Hernández Menárguez, Fernando; Abellán Alemán, José

Atrial fibrillation (AF) is the most common cardiac arrhythmia. To assess the need for anticoagulation is essential for its management. Our objective was to investigate whether the indication of anticoagulation was adequate in patients diagnosed with non-valvular AF, given the CHA2-DS2-VASc scale, measuring the International Normalizad Ratio range (INR) in patients treated with anti-vitamin K drugs. This is an observational and cross sectional study. 232 patients with atrial fibrillation were included. We analyzed demographic, the CHA2-DS2-VASc and HAS-BLED variables, the treatment and INR values for 6 consequentive months. The confrontation of variables was performed using chi-square and Mantel-Haenzel test. The prevalence of AF was 1.05%. The 88.4% had CHA2-DS2-VASc ≥ 2. The 71.1% were taking anticoagulants, of which 58.2% were under antivitamin k. The 46.7% of patients taking antivitamin K, presented inadequate range of INR. There was a greater prescription of antivitamin k in patients with persistent or permanent AF compared to the paroxysmal form (62.8 vs. 37.2% p<.001). The use of drugs that increase bleeding was associated with a worse control of INR after adjustment for the main variables of clinical relevance (odds ratio 2.17 [1.02-4.59], p=.043). The level of anticoagulation with antivitamin K was inadequate in our sample, despite a proper follow up and adherence to treatment. Patients with paroxysmal AF received less antivitamin K than those with persistent/permanent AF. Copyright © 2017 Sociedad Española de Arteriosclerosis. Publicado por Elsevier España, S.L.U. All rights reserved.

Comparison of Rhythm and Rate Control Strategies for Stroke Occurrence in a Prospective Cohort of Atrial Fibrillation Patients.

PubMed

Choi, Yu Jeong; Kang, Ki Woon; Kim, Tae Hoon; Cha, Myung Jin; Lee, Jung Myung; Park, Junbeom; Park, Jin Kyu; Shim, Jaemin; Uhm, Jae Sun; Kim, Jun; Park, Hyung Wook; Choi, Eue Keun; Kim, Jin Bae; Kim, Changsoo; Lee, Young Soo; Joung, Boyoung

2018-03-01

Comparisons of rhythm and rate control strategies for stroke prevention in patients with atrial fibrillation (AF) are still inconclusive. We compared differences in clinical outcomes between the rhythm and rate control strategies. The COmparison study of Drugs for symptom control and complication prEvention of Atrial Fibrillation (CODE-AF) registry prospectively enrolled 6000 patients who were treated for AF using real-world guideline adherence at multiple referral centers. In total, 2508 (41.8%) patients were clinically followed up for over six months. Of these, 1134 (45.2 %) patients treated by rhythm control and 1374 (54.8 %) patients treated by rate control were analyzed for clinical outcomes, including stroke and cardiovascular outcomes. Among all patients (age, 68±10 years; male, 62.4%), those treated with the rhythm control strategy were significantly younger, had more symptomatic paroxysmal AF, and a shorter AF duration, and were less likely to have diabetes, renal dysfunction, and heart failure, compared to those treated with the rate control strategy (CHA₂DS₂-VASc score 2.4±1.5 vs. 3.1±1.7, p<0.001). Even though oral anticoagulation was similarly prescribed in both groups, occurrence of stroke was less likely to occur in the rhythm control strategy group (0.0% vs. 0.7%, p=0.015). Multivariate Cox hazard regression showed that only age, especially more than 75 years old, were significantly correlated with the occurrence of stroke, regardless of the strategy used for treatment. In this prospective AF cohort, compared with the rate control strategy, the rhythm control strategy was associated with fewer cardiovascular events and strokes in a short-term period. © Copyright: Yonsei University College of Medicine 2018

Beyond Stroke Prevention in Atrial Fibrillation: Exploring Further Unmet Needs with Rivaroxaban.

PubMed

Gibson, C M; Hankey, G J; Nafee, T; Welsh, R C

2018-03-22

With improved life expectancy and the aging population, the global burden of atrial fibrillation (AF) continues to increase, and with AF comes an estimated fivefold increased risk of ischaemic stroke. Prophylactic anticoagulant therapy is more effective in reducing the risk of ischaemic stroke in AF patients than acetylsalicylic acid or dual-antiplatelet therapy combining ASA with clopidogrel. Non-vitamin K antagonist oral anticoagulants are the standard of care for stroke prevention in patients with non-valvular AF. The optimal anticoagulant strategy to prevent thromboembolism in AF patients who are undergoing percutaneous coronary intervention and stenting, those who have undergone successful transcatheter aortic valve replacement and those with embolic stroke of undetermined source are areas of ongoing research. This article provides an update on three randomized controlled trials of rivaroxaban, a direct, oral factor Xa inhibitor, that are complete or are ongoing, in these unmet areas of stroke prevention: oPen-label, randomized, controlled, multicentre study explorIng twO treatmeNt stratEgiEs of Rivaroxaban and a dose-adjusted oral vitamin K antagonist treatment strategy in patients with Atrial Fibrillation who undergo Percutaneous Coronary Intervention (PIONEER AF-PCI) trial; the New Approach riVaroxaban Inhibition of factor Xa in a Global trial vs Aspirin to prevenT Embolism in Embolic Stroke of Undetermined Source (NAVIGATE ESUS) trial and the Global study comparing a rivAroxaban-based antithrombotic strategy to an antipLatelet-based strategy after transcatheter aortIc vaLve rEplacement to Optimize clinical outcomes (GALILEO) trial. The data from these studies are anticipated to help address continuing challenges for a range of patients at risk of stroke. Schattauer.

Association of cardiac cachexia and atrial fibrillation in heart failure patients.

PubMed

Arámbula-Garza, Estefanía; Castillo-Martínez, Lilia; González-Islas, Dulce; Orea-Tejeda, Arturo; Santellano-Juárez, Brenda; Keirns-Davies, Candace; Peláez-Hernández, Viridiana; Sánchez-Santillán, Rocío; Pineda-Juárez, Juan; Cintora-Martínez, Carlos; Pablo-Santiago, Ruth

2016-11-15

Cachexia is a common complication in patients with advanced heart failure (HF) associated with inflammatory response activation. Atrial fibrillation (AF) is the most frequent arrhythmia (26%), probably both exacerbate the cardiac cachexia (CC). Evaluate the association of cardiac cachexia and atrial fibrillation in heart failure patients. In a case control study, CC was diagnosed by electrical bioimpedance with vectorial analysis (BIVA). Subjects with congenital heart disease, cancer, HIV, drug use and other causes than HF were excluded. Of the 359 subjects analyzed (men: 52.9%) median age 65years (55-74). Those with CC were older [72 (61-67)] vs. without [62 (52-70) years old, p<0.01]. During follow-up 47.8% of subjects developed CC and 17.27% AF, this was significantly more frequent in cachectic patients CC (23% vs 12.11%, OR: 2.17, 95% CI: 1.19-4.01, p=0.006). Subjects, with AF had lower left ventricular ejection fraction (25.49±12.96 vs. 32.01±15.02, p=0.08), lower posterior wall thickness (10.03±2.12 vs. 11.00±2.47, p=0.007), larger diameter of the left atrium (49.87±9.84 vs. 42.66±7.56, p<0.001), and a higher prevalence of CC (85.42% vs. 69.77%, p=0.028). The 50.58% of was in NYHA class I. In NYHA III, 22.95% were in AF vs. 12.10% with not AF (p=0.027). The frequent coexistence of CC and AF as HF complications indicate greater severity of HF, regardless of its type of HF. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Early, de novo atrial fibrillation after coronary artery bypass grafting: Facts and features.

PubMed

Yaksh, Ameeta; Kik, Charles; Knops, Paul; van Ettinger, Maarten J B; Bogers, Ad J J C; de Groot, Natasja M S

2017-02-01

Knowledge of the mechanism underlying post-operative atrial fibrillation (PoAF) is essential for development of preventive measures. The incidence and characteristics of both PoAF and supraventricular premature beats triggering PoAF, their interrelationship and alterations over time have never been examined. The goal of this study is therefore to examine the correlation between the incidence and characteristics of supraventricular premature beats (SVPBs) and PoAF episodes in patients undergoing CABG in the first five post-operative days. PoAF episodes (N=327) and SVPBs (N=141,873) were characterized in 29 patients (63±9 years; 22 (76%) male) undergoing coronary artery bypass grafting and compared with a control group of patients without PoAF by using continuous cardiac rhythm monitoring during the first 5 days after surgery. Most patients (N=18, 62%) had multiple PoAF episodes; the median number of PoAF episodes per patient was 3 and varied between 1 and 139. The majority of PoAF episodes developed on the second and third post-operative day (55%). The averaged median duration of PoAF episodes per patient was 469±1085 min. Patients with PoAF had a higher SVPBs burden compared to subjects without PoAF (0.9% vs 0.2%, P<.001). SVPBs initiating PoAF had shorter coupling intervals than SVPBs which did not initiate PoAF episodes (58% vs 64% (P<.001) and were preceded by heart rate acceleration. PoAF episodes are mainly repetitive though transient in nature. There was a considerable inter-individual variation in both AF and SVPB characteristics, despite a similar underlying clinical profile. The SVPB burden is higher in patients with PoAF and the mode of onset is characterized by short coupled SVPBs. Determination of individual post-operative dysrhythmia profiles enables identification of patients at risk for developing PoAF. Copyright © 2016 Elsevier Inc. All rights reserved.

Is HATCH score a reliable predictor of atrial fibrillation after cavotricuspid isthmus ablation for typical atrial flutter?

PubMed

García-Seara, Javier; Gude Sampedro, Francisco; Martínez Sande, Jose L; Fernández López, Xesus Alberte; Rodríguez Mañero, Moisés; González Melchor, Laila; Alvarez Alvarez, Belén; Iglesias Alvarez, Diego; González Juanatey, José Ramón

2016-09-01

We determined the effectiveness of the HATCH score in patients with typical atrial flutter (AFl) undergoing cavotricuspid isthmus (CTI) ablation to predict long-term atrial fibrillation (AF). We conducted an observational retrospective single-center cohort study including all patients admitted to our hospital for a CTI ablation between 1998 and 2010. The patients were divided into four categories: 1) new-onset AF (no prior AF and AF during follow-up (FU)); 2) old AF (prior AF and no AF during FU); 3) prior and post AF (AF prior and post CTI ablation); and 4) no AF. Four hundred and eight patients were included. In patients without prior AF, the hazard ratio (HR) for new-onset AF during FU was 0.98 (CI 95%: 0.65-1.50; p = 0.95) and 1.00 (CI 95%: 0.57-1.77; p = 0.98) for HATCH ≥ 2 and HATCH ≥ 3, respectively. In patients with prior AF, the HR for AF was 1.41 (CI 95%: 0.87-2.28; p = 0.17) and 1.79 (CI 95%: 0.96-3.35; p = 0.06), for HATCH ≥ 2 and HATCH ≥ 3, respectively. Left atrial enlargement was positively correlated with the occurrence of AF during FU, especially in the subgroup without prior AF, which had a HR of 2.44 (CI 95%: 1.35-4.40; p = 0.003), a HR of 2.88 (CI 95%: 1.36-6.10; p = 0.006) and a HR of 3.68 (CI 95%: 1.71-7.94; p = 0.001), for slight, moderate and severely dilated left atrial dimension, respectively, compared with a normal value. HATCH score did not predict AF in patients with typical AFl who underwent CTI ablation. Basal left atrium dimension could help predict new-onset AF.

Device-identified atrial fibrillation at pacing clinics. Should it guide anticoagulation?

PubMed

Merinopoulos, Ioannis; Raphael, Claire E; Yardley, Alaina; Goonewardene, Manoj; Vassiliou, Vassilios S

2016-03-15

In recent years, there has been a significant increase in the number of devices implanted following improvement in their safety profile, extension of indications and reduction in cost. Although the reason remains largely the beneficial effect on heart rhythm stabilisation, implanted devices might also have additional advantages, notably identification of silent arrhythmia. Should clinicians therefore act on device-identified atrial fibrillation (AF) and should such identification be used to guide anticoagulation management? This review evaluates the current evidence on the management of device-identified asymptomatic AF. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Clinical significance of nutritional status in patients with atrial fibrillation: An overview of current evidence.

PubMed

Anaszewicz, Marzena; Budzyński, Jacek

2017-05-01

Obesity is a well-known atherosclerosis risk factor; however, its role and the importance of undernutrition in atrial fibrillation (AF) pathogenesis are still not well understood. The aim of this study was to present the current state of knowledge on this issue in different groups of patients. Systematic review of papers published between 1980 and 2016. The literature shows contradicting views regarding the impact of nutritional status on the risk, course, and complications of AF. On the one hand, it has been revealed that overweight, obesity, and high birth mass increase the risk of AF, and that their reduction is linked to an improved course of AF and reduced all-cause and cardiovascular mortality. On the other hand, a so-called obesity paradox has been found, which shows lower all-cause mortality in overweight patients with AF compared to those of normal weight or who are underweight. It has also been shown, although based on a small number of studies, that the relationship between nutritional status and risk of AF and its complication may be U-shaped, which means that not only patients with obesity, but also individuals with underweight, cachexia, and low birth weight may have an increased risk and poor outcome of AF. The relationship between patients' nutritional status and the course of AF has become clearer but it requires further studies examining the importance of weight reduction on AF course. Copyright © 2016 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Both Hypothyroidism and Hyperthyroidism Increase Atrial Fibrillation Inducibility in Rats

PubMed Central

Zhang, Youhua; Dedkov, Eduard I.; Teplitsky, Diana; Weltman, Nathan Y.; Pol, Christine J.; Rajagopalan, Viswanathan; Lee, Bianca; Gerdes, A. Martin

2014-01-01

Background Evidence indicates that cardiac hypothyroidism may contribute to heart failure (HF) progression. It is also known that HF is associated with an increased risk of atrial fibrillation (AF). While it is established that hyperthyroidism increases AF incidence, the effect of hypothyroidism on AF is unclear. This study investigated the effects of different thyroid hormone levels, ranging from hypothyroidism to hyperthyroidism on AF inducibility in thyroidectomized rats. Methods and Results Thyroidectomized rats with serum confirmed hypothyroidism 1 month after surgery were randomized into hypothyroid (n=9), euthyroid (n=9) and hyperthyroid (n=9) groups. Rats received placebo, 3.3mg L-thyroxine (T4), or 20 mg T4 pellets (60 day release form) for 2 months, respectively. At the end of treatment, hypothyroid, euthyroid and hyperthyroid status was confirmed. Hypothyroid animals showed cardiac atrophy and reduced cardiac systolic and diastolic function, while hyperthyroid rats exhibited cardiac hypertrophy and increased cardiac function. Hypothyroidism and hyperthyroidism produced opposite electrophysiological changes in heart rates and atrial effective refractory period, but both significantly increased AF susceptibility. AF incidence was 78% in hypothyroid, 67% in hyperthyroid, and the duration of induced AF was also longer, compared with 11% in the euthyroid group (all p<0.05). Hypothyroidism increased atrial interstitial fibrosis, but connexin 43 was not affected. Conclusions Both hypothyroidism and hyperthyroidism lead to increased AF vulnerability in a rat thyroidectomy model. Our results stress that normal thyroid hormone levels are required to maintain normal cardiac electrophysiology and prevent cardiac arrhythmias and AF. PMID:24036190

Evaluating the Atrial Myopathy Underlying Atrial Fibrillation: Identifying the Arrhythmogenic and Thrombogenic Substrate

PubMed Central

Goldberger, Jeffrey J.; Arora, Rishi; Green, David; Greenland, Philip; Lee, Daniel C.; Lloyd-Jones, Donald M.; Markl, Michael; Ng, Jason; Shah, Sanjiv J.

2015-01-01

Atrial disease or myopathy forms the substrate for atrial fibrillation (AF) and underlies the potential for atrial thrombus formation and subsequent stroke. Current diagnostic approaches in patients with AF focus on identifying clinical predictors with evaluation of left atrial size by echocardiography serving as the sole measure specifically evaluating the atrium. Although the atrial substrate underlying AF is likely developing for years prior to the onset of AF, there is no current evaluation to identify the pre-clinical atrial myopathy. Atrial fibrosis is one component of the atrial substrate that has garnered recent attention based on newer MRI techniques that have been applied to visualize atrial fibrosis in humans with prognostic implications regarding success of treatment. Advanced ECG signal processing, echocardiographic techniques, and MRI imaging of fibrosis and flow provide up-to-date approaches to evaluate the atrial myopathy underlying AF. While thromboembolic risk is currently defined by clinical scores, their predictive value is mediocre. Evaluation of stasis via imaging and biomarkers associated with thrombogenesis may provide enhanced approaches to assess risk for stroke in patients with AF. Better delineation of the atrial myopathy that serves as the substrate for AF and thromboembolic complications might improve treatment outcomes. Furthermore, better delineation of the pathophysiologic mechanisms underlying the development of the atrial substrate for AF, particularly in its earlier stages, could help identify blood and imaging biomarkers that could be useful to assess risk for developing new onset AF and suggest specific pathways that could be targeted for prevention. PMID:26216085

Critical phase transitions during ablation of atrial fibrillation

NASA Astrophysics Data System (ADS)

Iravanian, Shahriar; Langberg, Jonathan J.

2017-09-01

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia with significant morbidity and mortality. Pharmacological agents are not very effective in the management of AF. Therefore, ablation procedures have become the mainstay of AF management. The irregular and seemingly chaotic atrial activity in AF is caused by one or more meandering spiral waves. Previously, we have shown the presence of sudden rhythm organization during ablation of persistent AF. We hypothesize that the observed transitions from a disorganized to an organized rhythm is a critical phase transition. Here, we explore this hypothesis by simulating ablation in an anatomically-correct 3D AF model. In 722 out of 2160 simulated ablation, at least one sudden transition from AF to an organized rhythm (flutter) was noted (33%). They were marked by a sudden decrease in the cycle length entropy and increase in the mean cycle length. At the same time, the number of reentrant wavelets decreased from 2.99 ± 0.06 in AF to 1.76 ± 0.05 during flutter, and the correlation length scale increased from 13.3 ± 1.0 mm to 196.5 ± 86.6 mm (both P < 0.0001). These findings are consistent with the hypothesis that transitions from AF to an anatomical flutter behave as phase transitions in complex non-equilibrium dynamical systems with flutter acting as an absorbing state. Clinically, the facilitation of phase transition should be considered a novel mechanism of ablation and may help to design effective ablation strategies.

Both hypothyroidism and hyperthyroidism increase atrial fibrillation inducibility in rats.

PubMed

Zhang, Youhua; Dedkov, Eduard I; Teplitsky, Diana; Weltman, Nathan Y; Pol, Christine J; Rajagopalan, Viswanathan; Lee, Bianca; Gerdes, A Martin

2013-10-01

Evidence indicates that cardiac hypothyroidism may contribute to heart failure progression. It is also known that heart failure is associated with an increased risk of atrial fibrillation (AF). Although it is established that hyperthyroidism increases AF incidence, the effect of hypothyroidism on AF is unclear. This study investigated the effects of different thyroid hormone levels, ranging from hypothyroidism to hyperthyroidism on AF inducibility in thyroidectomized rats. Thyroidectomized rats with serum-confirmed hypothyroidism 1 month after surgery were randomized into hypothyroid (N=9), euthyroid (N=9), and hyperthyroid (N=9) groups. Rats received placebo, 3.3-mg l-thyroxine (T4), or 20-mg T4 pellets (60-day release form) for 2 months, respectively. At the end of treatment, hypothyroid, euthyroid, and hyperthyroid status was confirmed. Hypothyroid animals showed cardiac atrophy and reduced cardiac systolic and diastolic functions, whereas hyperthyroid rats exhibited cardiac hypertrophy and increased cardiac function. Hypothyroidism and hyperthyroidism produced opposite electrophysiological changes in heart rates and atrial effective refractory period, but both significantly increased AF susceptibility. AF incidence was 78% in hypothyroid, 67% in hyperthyroid, and the duration of induced AF was also longer, compared with 11% in the euthyroid group (all P<0.05). Hypothyroidism increased atrial interstitial fibrosis, but connexin 43 was not affected. Both hypothyroidism and hyperthyroidism lead to increased AF vulnerability in a rat thyroidectomy model. Our results stress that normal thyroid hormone levels are required to maintain normal cardiac electrophysiology and to prevent cardiac arrhythmias and AF.

Rivaroxaban vs. warfarin in Japanese patients with atrial fibrillation – the J-ROCKET AF study –.

PubMed

Hori, Masatsugu; Matsumoto, Masayasu; Tanahashi, Norio; Momomura, Shin-ichi; Uchiyama, Shinichiro; Goto, Shinya; Izumi, Tohru; Koretsune, Yukihiro; Kajikawa, Mariko; Kato, Masaharu; Ueda, Hitoshi; Iwamoto, Kazuya; Tajiri, Masahiro

2012-01-01

The global ROCKET AF study evaluated once-daily rivaroxaban vs. warfarin for stroke and systemic embolism prevention in patients with atrial fibrillation (AF). A separate trial, J-ROCKET AF, compared the safety of a Japan-specific rivaroxaban dose with warfarin administered according to Japanese guidelines in Japanese patients with AF. J-ROCKET AF was a prospective, randomized, double-blind, phase III trial. Patients (n=1,280) with non-valvular AF at increased risk for stroke were randomized to receive 15 mg once-daily rivaroxaban or warfarin dose-adjusted according to Japanese guidelines. The primary objective was to determine non-inferiority of rivaroxaban against warfarin for the principal safety outcome of major and non-major clinically relevant bleeding, in the on-treatment safety population. The primary efficacy endpoint was the composite of stroke and systemic embolism. Non-inferiority of rivaroxaban to warfarin was confirmed; the rate of the principal safety outcome was 18.04% per year in rivaroxaban-treated patients and 16.42% per year in warfarin-treated patients (hazard ratio [HR] 1.11; 95% confidence interval 0.87-1.42; P<0.001 [non-inferiority]). Intracranial hemorrhage rates were 0.8% with rivaroxaban and 1.6% with warfarin. There was a strong trend for a reduction in the rate of stroke/systemic embolism with rivaroxaban vs. warfarin (HR, 0.49; P=0.050). J-ROCKET AF demonstrated the safety of a Japan-specific rivaroxaban dose and supports bridging the global ROCKET AF results into Japanese clinical practice.

Stroke prevention in atrial fibrillation and 'real world' adherence to guidelines in the Balkan Region: The BALKAN-AF Survey.

PubMed

Potpara, Tatjana S; Dan, Gheorghe-Andrei; Trendafilova, Elina; Goda, Artan; Kusljugic, Zumreta; Manola, Sime; Music, Ljilja; Musetescu, Rodica; Badila, Elisabeta; Mitic, Gorana; Paparisto, Vilma; Dimitrova, Elena S; Polovina, Marija M; Petranov, Stanislav L; Djergo, Hortensia; Loncar, Daniela; Bijedic, Amira; Brusich, Sandro; Lip, Gregory Y H

2016-02-12

Data on the management of atrial fibrillation (AF) in the Balkan Region are limited. The Serbian AF Association (SAFA) prospectively investigated contemporary 'real-world' AF management in clinical practice in Albania, Bosnia&Herzegovina, Bulgaria, Croatia, Montenegro, Romania and Serbia through a 14-week (December 2014-February 2015) prospective, multicentre survey of consecutive AF patients. We report the results pertinent to stroke prevention strategies. Of 2712 enrolled patients, 2663 (98.2%) with complete data were included in this analysis (mean age 69.1 ± 10.9 years, female 44.6%). Overall, 1960 patients (73.6%) received oral anticoagulants (OAC) and 762 (28.6%) received antiplatelet drugs. Of patients given OAC, 17.2% received non-vitamin K antagonist oral anticoagulants (NOACs). CHA2DS2-VASc score was not significantly associated with OAC use. Of the 'truly low-risk' patients (CHA2DS2-VASc = 0 [males], or 1 [females]) 56.5% received OAC. Time in Therapeutic Range (TTR) was available in only 18.7% of patients (mean TTR: 49.5% ± 22.3%). Age ≥ 80 years, prior myocardial infarction and paroxysmal AF were independent predictors of OAC non-use. Our survey shows a relatively high overall use of OAC in AF patients, but with low quality of vitamin K antagonist therapy and insufficient adherence to AF guidelines. Additional efforts are needed to improve AF-related thromboprophylaxis in clinical practice in the Balkan Region.

Chocolate consumption and risk of atrial fibrillation: Two cohort studies and a meta-analysis.

PubMed

Larsson, Susanna C; Drca, Nikola; Jensen-Urstad, Mats; Wolk, Alicja

2018-01-01

Chocolate consumption has been inconsistently associated with risk of atrial fibrillation (AF). We investigated the association between chocolate consumption and risk of AF in Swedish adults from two cohort studies and conducted a meta-analysis to summarize available evidence from cohort studies on this topic. Our study population comprised 40,009 men from the Cohort of Swedish Men and 32,486 women from the Swedish Mammography Cohort. Incident AF cases were ascertained through linkage with the Swedish National Patient Register. Published cohort studies of chocolate consumption in relation to risk of AF were identified by a PubMed search through September 14, 2017. During a mean follow-up of 14.6 years, AF was diagnosed in 9978 Swedish men and women. Compared with non-consumers, the multivariable hazard ratio of AF for those in the highest category of chocolate consumption (≥3-4 servings/week) was 0.96 (95% CI 0.88-1.04). In a random-effects meta-analysis of 5 cohort studies, including 180,454 participants and 16,356 AF cases, the hazard ratios of AF were 0.97 (95% CI 0.94-1.01) per 2 servings/week increase in chocolate consumption and 0.96 (95% CI 0.90-1.03) for the highest versus lowest category of chocolate consumption. Available data provide no evidence of an association of chocolate consumption with risk of AF. Copyright © 2017 Elsevier Inc. All rights reserved.

Intravenous sotalol decreases transthoracic cardioversion energy requirement for chronic atrial fibrillation in humans: assessment of the electrophysiological effects by biatrial basket electrodes.

PubMed

Lai, L P; Lin, J L; Lien, W P; Tseng, Y Z; Huang, S K

2000-05-01

This study was undertaken to assess the effects of sotalol on the transthoracic cardioversion energy requirement for chronic atrial fibrillation (AF) and on the atrial electrograms during AF recorded by two basket electrodes. The effects of sotalol infusion on transthoracic electrical cardioversion for chronic atrial fibrillation in humans have not been well investigated. We included 18 patients with persistent AF for more than three months. Atrial electrograms were recorded by two basket electrodes positioned in each atrium respectively. Transthoracic cardioversion was performed before and after sotalol 1.5 mg/kg i.v. infusion. In the 14 patients whose AF could be terminated by cardioversion before sotalol infusion, the atrial defibrillation energy was significantly reduced after sotalol infusion (236 +/- 74 jules [J] vs. 186 +/- 77 J; p < 0.01). Atrial fibrillation was refractory to cardioversion in four patients at baseline and was converted to sinus rhythm by cardioversion after sotalol infusion in two of them. We further divided the patients into two groups. Group A consisted of 10 patients in whom the energy requirement was decreased by sotalol while group B consisted of eight patients in whom the energy requirement was not decreased. The mean A-A (atrial local electrogram) intervals during AF were significantly increased after sotalol infusion in both groups, but the increment of A-A interval was significantly larger in group A than it was in group B patients (36 +/- 13 ms vs. 22 +/- 8 ms for the right atrium; 19 +/- 7 ms vs. 9 +/- 7 ms for the left atrium; both p < 0.05). The spatial and temporal dispersions of A-A intervals were not significantly changed after sotalol infusion in both atria in both groups. Sotalol decreases the atrial defibrillation energy requirement by increasing atrial refractoriness but not by decreasing the dispersion of refractoriness.

[Interrelationship between lower limb varicosity, the grade of connective tissue dysplasia and atrial fibrillation in patients with coronary artery disease].

PubMed

Forster, O V; Tsarev, O A; Shvarts, Iu G

2006-01-01

To determine interrelationship between lower limb varicosity, the clinical grade of non-differentiated dysplasia of the connective tissue and atrial fibrillation in patients with coronary artery disease (CAD). Altogether 156 coronary patients were examined. Persistent atrial fibrillation was present in 58 and chronic in 38 patients. The reference group comprised 60 patients without evident rhythm disorders in persons suffering from CAD. Markers of connective tissue dysplasia () were revealed on the part of the skeleton, joints skin and visceral organs. Lower limb varicosity was recorded as well. The number of the stigmas in the study groups was different. So, in the patient group without rhythm disorders, the mean number of the stigmas was equal to 3, which is a variant of normal. In the groups with persistent and constant AF, this indicator was equal to 4.7 and 5.2 respectively (p<0.05). The number of patients with evident signs of CID (the number of stigmas 5) was greater in the groups with AP than among patients with normal rhythm. Varicosity was recorded in 41% of both group patients. It is to be noted that in the group with normal rhythm, lower limb varicosity was encountered in 22.1% of cases whereas in the group with AF, in 58.4% of cases with persistent AF and in 41% of cases with constant AF. The mean number of stigmas in the group without varicosity accounted for 3.6 and in patients with varicosity - for 5 (P<0.05). When coronary artery disease is coupled with atrial fibrilation there is a direct close correlation between the signs of connective tissue dysplasia and lower limb varicosity. In patients with persistent AF lower limb varicosity occurs more frequently than in CAD patients with normal rhythm.

Assessment of Remote Heart Rhythm Sampling Using the AliveCor Heart Monitor to Screen for Atrial Fibrillation: The REHEARSE-AF Study.

PubMed

Halcox, Julian P J; Wareham, Kathie; Cardew, Antonia; Gilmore, Mark; Barry, James P; Phillips, Ceri; Gravenor, Michael B

2017-11-07

Asymptomatic atrial fibrillation (AF) is increasingly common in the aging population and implicated in many ischemic strokes. Earlier identification of AF with appropriate anticoagulation may decrease stroke morbidity and mortality. We conducted a randomized controlled trial of AF screening using an AliveCor Kardia monitor attached to a WiFi-enabled iPod to obtain ECGs (iECGs) in ambulatory patients. Patients ≥65 years of age with a CHADS-VASc score ≥2 free from AF were randomized to the iECG arm or routine care (RC). iECG participants acquired iECGs twice weekly over 12 months (plus additional iECGs if symptomatic) onto a secure study server with overread by an automated AF detection algorithm and by a cardiac physiologist and/or consultant cardiologist. Time to diagnosis of AF was the primary outcome measure. The overall cost of the devices, ECG interpretation, and patient management were captured and used to generate the cost per AF diagnosis in iECG patients. Clinical events and patient attitudes/experience were also evaluated. We studied 1001 patients (500 iECG, 501 RC) who were 72.6±5.4 years of age; 534 were female. Mean CHADS-VASc score was 3.0 (heart failure, 1.4%; hypertension, 54%; diabetes mellitus, 30%; prior stroke/transient ischemic attack, 6.5%; arterial disease, 15.9%; all CHADS-VASc risk factors were evenly distributed between groups). Nineteen patients in the iECG group were diagnosed with AF over the 12-month study period versus 5 in the RC arm (hazard ratio, 3.9; 95% confidence interval=1.4-10.4; P =0.007) at a cost per AF diagnosis of $10 780 (£8255). There was a similar number of stroke/transient ischemic attack/systemic embolic events (6 versus 10, iECG versus RC; hazard ratio=0.61; 95% confidence interval=0.22-1.69; P =0.34). The majority of iECG patients were satisfied with the device, finding it easy to use without restricting activities or causing anxiety. Screening with twice-weekly single-lead iECG with remote interpretation in ambulatory patients ≥65 years of age at increased risk of stroke is significantly more likely to identify incident AF than RC over a 12-month period. This approach is also highly acceptable to this group of patients, supporting further evaluation in an appropriately powered, event-driven clinical trial. URL: https://www.isrctn.com. Unique identifier: ISRCTN10709813. © 2017 American Heart Association, Inc.

Biatrial Electrical and Structural Atrial Changes in Heart Failure: Electroanatomic Mapping in Persistent Atrial Fibrillation in Humans.

PubMed

Prabhu, Sandeep; Voskoboinik, Aleksandr; McLellan, Alex J A; Peck, Kah Y; Pathik, Bhupesh; Nalliah, Chrishan J; Wong, Geoff R; Azzopardi, Sonia M; Lee, Geoffrey; Mariani, Justin; Ling, Liang-Han; Taylor, Andrew J; Kalman, Jonathan M; Kistler, Peter M

2018-01-01

This study sought to characterize the biatrial substrate in heart failure (HF) and persistent atrial fibrillation (PeAF). Atrial fibrillation (AF) and HF frequently coexist; however, the contribution of HF to the biatrial substrate in PeAF is unclear. Consecutive patients with PeAF and normal left ventricular (NLV) systolic function (left ventricular ejection fraction [LVEF] >55%) or idiopathic cardiomyopathy (LVEF ≤45%) undergoing AF ablation were enrolled. In AF, pulmonary vein (PV) cycle length (PVCL) was recorded via a multipolar catheter in each PV and in the left atrial appendage for 100 consecutive cycles. After electrical cardioversion, biatrial electroanatomic mapping was performed. Complex electrograms, voltage, scarring, and conduction velocity were assessed. Forty patients, 20 patients with HF (mean age: 62 ± 8.9 years; AF duration: 15 ± 11 months; LVEF: 33 ± 8.4%) and 20 with NLV (mean age: 59 ± 6.7 years; AF duration: 14 ± 9.1 months; p = 0.69; mean LVEF: 61 ± 3.6%; p < 0.001), were enrolled. HF reduced biatrial tissue voltage (p < 0.001) with greater voltage heterogeneity (p < 0.001). HF was associated with significantly more biatrial fractionation (left atrium [LA]: 30% vs. 9%; p < 0.001; right atrium [RA]: 28% vs. 11%; p < 0.001), low voltage (<0.5 mV) (LA: 23% vs. 6%; p = 0.002; RA: 20% vs 11%; p = 0.006), and scarring (<0.05 mV) in the LA (p = 0.005). HF was associated with a slower average PVCL (185 vs. 164 ms; p = 0.016), which correlated significantly with PV antral bipolar voltage (R = -0.62; p < 0.001) and fractionation (R = 0.46; p = 0.001). HF is associated with significantly reduced biatrial tissue voltage, fractionation, and prolongation of PVCL. Advanced biatrial remodeling may have implications for invasive and noninvasive rhythm control strategies in patients with AF and HF. Copyright © 2018 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Efficacy and safety of rivaroxaban in patients with diabetes and nonvalvular atrial fibrillation: the Rivaroxaban Once-daily, Oral, Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF Trial).

PubMed

Bansilal, Sameer; Bloomgarden, Zachary; Halperin, Jonathan L; Hellkamp, Anne S; Lokhnygina, Yuliya; Patel, Manesh R; Becker, Richard C; Breithardt, Günter; Hacke, Werner; Hankey, Graeme J; Nessel, Christopher C; Singer, Daniel E; Berkowitz, Scott D; Piccini, Jonathan P; Mahaffey, Kenneth W; Fox, Keith A A

2015-10-01

The prevalence of both atrial fibrillation (AF) and diabetes mellitus (DM) are rising, and these conditions often occur together. Also, DM is an independent risk factor for stroke in patients with AF. We aimed to examine the safety and efficacy of rivaroxaban vs warfarin in patients with nonvalvular AF and DM in a prespecified secondary analysis of the ROCKET AF trial. We stratified the ROCKET AF population by DM status, assessed associations with risk of outcomes by DM status and randomized treatment using Cox proportional hazards models, and tested for interactions between randomized treatments. For efficacy, primary outcomes were stroke (ischemic or hemorrhagic) or non-central nervous system embolism. For safety, the primary outcome was major or nonmajor clinically relevant bleeding. The 5,695 patients with DM (40%) in ROCKET AF were younger, were more obese, and had more persistent AF, but fewer had previous stroke (the CHADS2 score includes DM and stroke). The relative efficacy of rivaroxaban and warfarin for prevention of stroke and systemic embolism was similar in patients with (1.74 vs 2.14/100 patient-years, hazard ratio [HR] 0.82) and without (2.12 vs 2.32/100 patient-years, HR 0.92) DM (interaction P = .53). The safety of rivaroxaban vs warfarin regarding major bleeding (HRs 1.00 and 1.12 for patients with and without DM, respectively; interaction P = .43), major or nonmajor clinically relevant bleeding (HRs 0.98 and 1.09; interaction P = .17), and intracerebral hemorrhage (HRs 0.62 and 0.72; interaction P = .67) was independent of DM status. Adjusted exploratory analyses suggested 1.3-, 1.5-, and 1.9-fold higher 2-year rates of stroke, vascular mortality, and myocardial infarction in DM patients. The relative efficacy and safety of rivaroxaban vs warfarin was similar in patients with and without DM, supporting use of rivaroxaban as an alternative to warfarin in diabetic patients with AF. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Cost-of-illness studies of atrial fibrillation: methodological considerations.

PubMed

Becker, Christian

2014-10-01

Atrial fibrillation (AF) is the most common heart rhythm arrhythmia, which has considerable economic consequences. This study aims to identify the current cost-of-illness estimates of AF; a focus was put on describing the studies' methodology. A literature review was conducted. Twenty-eight cost-of-illness studies were identified. Cost-of-illness estimates exist for health insurance members, hospital and primary care populations. In addition, the cost of stroke in AF patients and the costs of post-operative AF were calculated. The methods used were heterogeneous, mostly studies calculated excess costs. The identified annual excess costs varied, even among studies from the USA (∼US$1900 to ∼US$19,000). While pointing toward considerable costs, the cost-of-illness studies' relevance could be improved by focusing on subpopulations and treatment mixes. As possible starting points for subsequent economic studies, the methodology of cost-of-illness studies should be taken into account using methods, allowing stakeholders to find suitable studies and validate estimates.

Atrial fibrillation management in a breeding stallion.

PubMed

Heliczer, N; Mitchell, K; Lorello, O; Dauvillier, J; Burger, D; Schwarzwald, C C; Navas de Solis, C

2017-06-01

A 20-year-old warmblood breeding stallion presented to a University practice for semen collection and evaluation was incidentally diagnosed with atrial fibrillation (AF). Electrocardiogram recordings during breeding revealed inappropriately rapid tachycardia and occasional ventricular premature depolarizations/aberrant ventricular conduction. Transvenous electrical cardioversion was performed. After successful cardioversion the horse displayed supraventricular ectopy and atrial contractile dysfunction and was administered sotalol hydrochloride in an attempt to decrease the risk of AF recurrence. Supraventricular ectopy and echocardiographic evidence of atrial dysfunction gradually improved and normalized over 6 months. No direct adverse effects of the chronic anti-arrhythmic treatment were observed and libido and semen quality were unaffected. AF recurred 6 months after cardioversion and sotalol therapy was continued to control the ventricular ectopy/aberrant ventricular conduction during semen collection. Considerations regarding pathologic arrhythmias and inappropriately high heart rates in breeding stallions with AF may be similar to those in riding horses. Sotalol hydrochloride was a safe anti-arrhythmic drug in the management of this case. Copyright © 2017 Elsevier B.V. All rights reserved.

Simple Model for Identifying Critical Regions in Atrial Fibrillation

NASA Astrophysics Data System (ADS)

Christensen, Kim; Manani, Kishan A.; Peters, Nicholas S.

2015-01-01

Atrial fibrillation (AF) is the most common abnormal heart rhythm and the single biggest cause of stroke. Ablation, destroying regions of the atria, is applied largely empirically and can be curative but with a disappointing clinical success rate. We design a simple model of activation wave front propagation on an anisotropic structure mimicking the branching network of heart muscle cells. This integration of phenomenological dynamics and pertinent structure shows how AF emerges spontaneously when the transverse cell-to-cell coupling decreases, as occurs with age, beyond a threshold value. We identify critical regions responsible for the initiation and maintenance of AF, the ablation of which terminates AF. The simplicity of the model allows us to calculate analytically the risk of arrhythmia and express the threshold value of transversal cell-to-cell coupling as a function of the model parameters. This threshold value decreases with increasing refractory period by reducing the number of critical regions which can initiate and sustain microreentrant circuits. These biologically testable predictions might inform ablation therapies and arrhythmic risk assessment.

Pulmonary vein activity does not predict the outcome of catheter ablation for persistent atrial fibrillation: A long-term multicenter prospective study.

PubMed

Prabhu, Sandeep; Kalla, Manish; Peck, Kah Y; Voskoboinik, Aleksandr; McLellan, Alex J A; Pathik, Bupesh; Nalliah, Chrishan J; Wong, Geoff R; Sugumar, Hariharan; Azzopardi, Sonia M; Lee, Geoffrey; Ling, Liang-Han; Kalman, Jonathan M; Kistler, Peter M

2018-03-02

Pulmonary vein (PV) isolation (PVI) remains the cornerstone of catheter ablation (CA) in persistent atrial fibrillation (AF) (PeAF), although less successful than for paroxysmal AF. Whether rapid or fibrillatory (PV AF) PV firing may identify patients with PeAF more likely to benefit from a PV-based ablation approach is unclear. The purpose of this study was to determine the relationship between the PV cycle length (PVCL) and the PV AF outcome after CA. Before ablation, the multipolar catheter was placed in each PV and the left atrial appendage (LAA) for 100 consecutive cycles. The presence of PV AF, the average PVCL of all 4 veins (PV 4VAverage ), the fastest vein average (PV FVAverage ), the fastest cycle length (PV Fast ) both individually and relative to the average LAA cycle length were calculated. The ablation strategy included PVI and posterior wall isolation with a minimum of 12 months follow-up. A total of 123 patients underwent CA (age 62 ± 9.1 years; CHA 2 DS 2 -VASC score 1.6 ± 1.1; left ventricular ejection fraction 48% ± 13%; left atrial area 31 ± 8.7 cm 2 ; AF duration 16 ± 17 months). PVI was achieved in 100% of patients. Multiprocedure success (MPS; freedom from AF/atrial tachycardia episodes lasting >30 seconds) was achieved in 76% of patients at 24 ± 8.1 months of follow-up after 1.2 ± 0.4 procedures. PV activity was not associated with MPS either absolutely (PV 4VAverage [MPS no vs yes: 178 ± 27 ms vs 177 ± 24 ms; P = .92], PV FVAverage [P = .69], or PV Fast [P = .82]) or as a ratio relative to the LAA cycle length (PV 4VAverage /LAA 1.05 ± 0.11 vs 1.06 ± 0.21; P = .87). The presence of PV AF (31% vs 47%; P = .13) did not predict MPS. The rapidity of PV firing or presence of fibrillation within the PV was not predictive of outcome of CA for PeAF. PV activity does not identify patients most likely to benefit from a PV-based ablation strategy. Copyright © 2018 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

An intelligent telecardiology system using a wearable and wireless ECG to detect atrial fibrillation.

PubMed

Lin, Chin-Teng; Chang, Kuan-Cheng; Lin, Chun-Ling; Chiang, Chia-Cheng; Lu, Shao-Wei; Chang, Shih-Sheng; Lin, Bor-Shyh; Liang, Hsin-Yueh; Chen, Ray-Jade; Lee, Yuan-Teh; Ko, Li-Wei

2010-05-01

This study presents a novel wireless, ambulatory, real-time, and autoalarm intelligent telecardiology system to improve healthcare for cardiovascular disease, which is one of the most prevalent and costly health problems in the world. This system consists of a lightweight and power-saving wireless ECG device equipped with a built-in automatic warning expert system. This device is connected to a mobile and ubiquitous real-time display platform. The acquired ECG signals are instantaneously transmitted to mobile devices, such as netbooks or mobile phones through Bluetooth, and then, processed by the expert system. An alert signal is sent to the remote database server, which can be accessed by an Internet browser, once an abnormal ECG is detected. The current version of the expert system can identify five types of abnormal cardiac rhythms in real-time, including sinus tachycardia, sinus bradycardia, wide QRS complex, atrial fibrillation (AF), and cardiac asystole, which is very important for both the subjects who are being monitored and the healthcare personnel tracking cardiac-rhythm disorders. The proposed system also activates an emergency medical alarm system when problems occur. Clinical testing reveals that the proposed system is approximately 94% accurate, with high sensitivity, specificity, and positive prediction rates for ten normal subjects and 20 AF patients. We believe that in the future a business-card-like ECG device, accompanied with a mobile phone, can make universal cardiac protection service possible.

Association between Heat Shock Protein-60 and Development of Atrial Fibrillation: Results from the Multi-Ethnic Study of Atherosclerosis (MESA).

PubMed

Maan, Abhishek; Jorgensen, Neal W; Mansour, Moussa; Dudley, Samuel; Jenny, Nancy S; Defilippi, Christopher; Szklo, Moyses; Alonso, Alvaro; Refaat, Marwan M; Ruskin, Jeremy; Heckbert, Susan R; Heist, E Kevin

2016-12-01

During atrial fibrillation (AF), a high rate of myocyte activation causes cellular stress and initiates the process of atrial remodeling, which further promotes persistence of AF. Although heat shock proteins (HSPs) have been shown to prevent atrial remodeling and suppress the occurrence of AF in cellular and animal experimental models, increased levels of HSP-60 have been observed in patients with postoperative AF, likely reflecting a response to cellular stress. To better understand the role of HSP-60 in relation to AF, we examined the association of HSP-60 levels in relation to the future development of AF in the Multi-Ethnic Study of Atherosclerosis (MESA). MESA is a cohort study that recruited 6,814 participants aged 45-84 years and free of known cardiovascular disease at baseline (2000-2002) from six field centers. We investigated 983 participants, selected at random from the total cohort, who had HSP-60 measured and were free of AF at baseline. We tested the association of HSP-60 levels with the incidence of AF using multivariate Cox models after adjustment for demographics, clinical characteristics, and biomarkers. During an average of 10.6 years of follow-up, 77 participants developed AF. We did not observe a significant association between the log-transformed HSP-60 levels and development of AF on either unadjusted or multivariate analysis (adjusted hazard ratio: 1.02 per unit difference on natural log scale, 95% confidence interval: 0.77-1.34 ln (ng/mL). Contrary to the findings from the preclinical studies, which demonstrated an important role of HSP-60 in the pathogenesis of AF, we did not observe a significant association between HSP-60 and occurrence of AF. © 2016 Wiley Periodicals, Inc.

Quality of life, activity impairment, and healthcare resource utilization associated with atrial fibrillation in the US National Health and Wellness Survey.

PubMed

Goren, Amir; Liu, Xianchen; Gupta, Shaloo; Simon, Teresa A; Phatak, Hemant

2013-01-01

This study builds upon current studies of atrial fibrillation (AF) and health outcomes by examining more comprehensively the humanistic burden of illness (quality of life, activity impairment, and healthcare resource utilization) among adult patients with AF, using a large, nationally representative sample and matched controls. Data were analyzed from the Internet-based 2009 US National Health and Wellness Survey. Outcomes were Mental and Physical Component Summary (MCS and PCS) and health utility scores from the SF-12, activity impairment, hospitalizations, and healthcare provider and emergency room (ER) visits. Patients with self-reported diagnosis of AF were matched randomly on age and gender with an equal number of respondents without AF. Generalized linear models examined outcomes as a function of AF vs. non-AF status, controlling for CHADS2 score, comorbidity counts, demographics, and clinical variables. Exploratory structural equation modeling assessed the above in an integrated model of humanistic burden. Mean age of AF patients (1,296 from a total sample of 75,000) was 64.9 years and 65.1% were male. Adjusting for covariates, compared with non-AF patients, AF patients had lower MCS, PCS, and utility scores, greater activity impairment (rate ratio = 1.26), more traditional provider visits (rate ratio = 1.43), and increased odds of ER visits (OR = 2.53) and hospitalizations (OR = 2.71). Exploratory structural equation modeling analyses revealed that persons with AF experienced a significantly higher overall humanistic burden. This study highlights and clarifies the substantial burden of AF and its implications for preparing efficacious AF management plans to address the imminent rise in prevalence.

Pulmonary Vein Isolation Alone Versus Additional Linear Ablation in Patients With Persistent Atrial Fibrillation Converted to Paroxysmal Type With Antiarrhythmic Drug Therapy: A Multicenter, Prospective, Randomized Study.

PubMed

Yu, Hee Tae; Shim, Jaemin; Park, Junbeom; Kim, In-Soo; Kim, Tae-Hoon; Uhm, Jae-Sun; Joung, Boyoung; Lee, Moon-Hyoung; Kim, Young-Hoon; Pak, Hui-Nam

2017-06-01

Atrial fibrillation (AF) type can vary depending on condition and timing, and some patients who initially present with persistent AF may be changed to paroxysmal AF after antiarrhythmic drug medication and cardioversion. We investigated whether circumferential pulmonary vein isolation (CPVI) alone is an effective rhythm control strategy in patients with persistent AF to paroxysmal AF. We enrolled 113 patients with persistent AF to paroxysmal AF (male 75%, 60.4±10.1 years old) who underwent catheter ablation for nonvalvular AF at 3 tertiary hospitals. The participants were randomly assigned to 2 groups: CPVI alone (n=59) or CPVI plus linear ablation (CPVI+Line; posterior box+anterior line, n=54). Compared with the CPVI+Line, CPVI alone required shorter procedure (187.2±58.0 versus 211.2±63.9 min; P =0.043) and ablation times (4922.1±1110.5 versus 6205.7±1425.2 s; P <0.001) without difference in procedure-related major complication (3% versus 2%; P =0.611). Antiarrhythmic drug utility rates after ablation were not different between the 2 groups (22% versus 30%; P =0.356). Overall, AF-free survival (log-rank; P =0.206) and AF and antiarrhythmic drug-free survival (log-rank; P =0.321) were not different between groups. CPVI alone is an effective rhythm control strategy with a shorter procedure time in persistent AF patients converted to paroxysmal AF compared with CPVI with linear ablation. URL: https://www.clinicaltrials.gov. Unique identifier: NCT02176616. © 2017 American Heart Association, Inc.

Association of Proteinuria and Incident Atrial Fibrillation in Patients With Intact and Reduced Kidney Function.

PubMed

Molnar, Amber O; Eddeen, Anan Bader; Ducharme, Robin; Garg, Amit X; Harel, Ziv; McCallum, Megan K; Perl, Jeffrey; Wald, Ron; Zimmerman, Deborah; Sood, Manish M

2017-07-06

Early evidence suggests proteinuria is independently associated with incident atrial fibrillation (AF). We sought to investigate whether the association of proteinuria with incident AF is altered by kidney function. Retrospective cohort study using administrative healthcare databases in Ontario, Canada (2002-2015). A total of 736 666 patients aged ≥40 years not receiving dialysis and with no previous history of AF were included. Proteinuria was defined using the urine albumin-to-creatinine ratio (ACR) and kidney function by the estimated glomerular filtration rate (eGFR). The primary outcome was time to AF. Cox proportional models were used to determine the hazard ratio for AF censored for death, dialysis, kidney transplant, or end of follow-up. Fine and Grey models were used to determine the subdistribution hazard ratio for AF, with death as a competing event. Median follow-up was 6 years and 44 809 patients developed AF. In adjusted models, ACR and eGFR were associated with AF ( P <0.0001). The association of proteinuria with AF differed based on kidney function (ACR × eGFR interaction, P <0.0001). Overt proteinuria (ACR, 120 mg/mmol) was associated with greater AF risk in patients with intact (eGFR, 120) versus reduced (eGFR, 30) kidney function (adjusted hazard ratios, 4.5 [95% CI, 4.0-5.1] and 2.6 [95% CI, 2.4-2.8], respectively; referent ACR 0 and eGFR 120). Results were similar in competing risk analyses. Proteinuria increases the risk of incident AF markedly in patients with intact kidney function compared with those with decreased kidney function. Screening and preventative strategies should consider proteinuria as an independent risk factor for AF. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Strict sequential catheter ablation strategy targeting the pulmonary veins and superior vena cava for persistent atrial fibrillation.

PubMed

Yoshiga, Yasuhiro; Shimizu, Akihiko; Ueyama, Takeshi; Ono, Makoto; Fukuda, Masakazu; Fumimoto, Tomoko; Ishiguchi, Hironori; Omuro, Takuya; Kobayashi, Shigeki; Yano, Masafumi

2018-08-01

An effective catheter ablation strategy, beyond pulmonary vein isolation (PVI), for persistent atrial fibrillation (AF) is necessary. Pulmonary vein (PV)-reconduction also causes recurrent atrial tachyarrhythmias. The effect of the PVI and additional effect of a superior vena cava (SVC) isolation (SVCI) was strictly evaluated. Seventy consecutive patients with persistent AF who underwent a strict sequential ablation strategy targeting the PVs and SVC were included in this study. The initial ablation strategy was a circumferential PVI. A segmental SVCI was only applied as a repeat procedure when patients demonstrated no PV-reconduction. After the initial procedure, persistent AF was suppressed in 39 of 70 (55.7%) patients during a median follow-up of 32 months. After multiple procedures, persistent AF was suppressed in 46 (65.7%) and 52 (74.3%) patients after receiving the PVI alone and PVI plus SVCI strategies, respectively. In 6 of 15 (40.0%) patients with persistent AF resistant to PVI, persistent AF was suppressed. The persistent AF duration independently predicted persistent AF recurrences after multiple PVI alone procedures [HR: 1.012 (95% confidence interval: 1.006-1.018); p<0.001] and PVI plus SVCI strategies [HR: 1.018 (95% confidence interval: 1.011-1.025); p<0.001]. A receiver-operating-characteristic analysis for recurrent persistent AF indicated an optimal cut-off value of 20 and 32 months for the persistent AF duration using the PVI alone and PVI plus SVCI strategies, respectively. The outcomes of the PVI plus SVCI strategy were favorable for patients with shorter persistent AF durations. The initial SVCI had the additional effect of maintaining sinus rhythm in some patients with persistent AF resistant to PVI. Copyright © 2018 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Incident Atrial Fibrillation and Risk of End-Stage Renal Disease in Adults with Chronic Kidney Disease

PubMed Central

Bansal, Nisha; Fan, Dongjie; Hsu, Chi-yuan; Ordonez, Juan D.; Marcus, Gregory M.; Go, Alan S.

2013-01-01

Background Atrial fibrillation (AF) frequently occurs in patients with chronic kidney disease (CKD). However, the long-term impact of development of AF on the risk of adverse renal outcomes in patients with CKD is unknown. In this study, we determined the association between incident AF and risk of end-stage renal disease (ESRD) among adults with CKD. Methods and Results We studied adults with CKD (defined as persistent glomerular filtration rate [eGFR] <60 ml/min/1.73 m2 by the CKD-EPI equation) enrolled in Kaiser Permanente Northern California who were identified between 2002–2010 and who did not have prior ESRD or previously documented AF. Incident AF was identified using primary hospital discharge diagnoses and/or two or more outpatient visits for AF. Incident ESRD was ascertained from a comprehensive health plan registry for dialysis and renal transplant. Among 206,229 adults with CKD, 16,463 developed incident AF. During a mean follow-up of 5.1± 2.5 years, there were 345 cases of ESRD that occurred after development of incident AF (74 per 1000 person-years) compared with 6505 cases of ESRD during periods without AF (64 per 1000 person-years, P<0.001). After adjustment for potential confounders, incident AF was associated with a 67% increase in rate of ESRD (hazard ratio 1.67, 95% confidence interval: 1.46–1.91). Conclusions Incident AF is independently associated with increased risk of developing ESRD in adults with CKD. Further study is needed to identify potentially modifiable pathways through which AF leads to a higher risk of progression to ESRD. PMID:23275377

Temporal trends in the occurrence and outcomes of atrial fibrillation in patients with acute myocardial infarction (from the Atherosclerosis Risk in Communities Surveillance Study).

PubMed

Bengtson, Lindsay G S; Chen, Lin Y; Chamberlain, Alanna M; Michos, Erin D; Whitsel, Eric A; Lutsey, Pamela L; Duval, Sue; Rosamond, Wayne D; Alonso, Alvaro

2014-09-01

Atrial fibrillation (AF) frequently coexists in the setting of myocardial infarction (MI), being associated with increased mortality. Nonetheless, temporal trends in the occurrence of AF complicating MI and in the prognosis of these patients are not well described. We examined temporal trends in prevalence of AF in the setting of MI and the effect of AF on prognosis in the community. We studied a population-based sample of 20,049 validated first-incident nonfatal hospitalized MIs among 35- to 74-year old residents of 4 communities in the Atherosclerosis Risk in Communities (ARIC) Study from 1987 through 2009. Prevalence of AF in the setting of MI increased from 11% to 15% during the 23-year study period. The multivariable adjusted odds ratio for prevalent AF, per 5-year increment, was 1.11 (95% confidence interval 1.04 to 1.19). Overall, in patients with MI, AF was associated with increased 1-year case fatality (odds ratio 1.47, 95% confidence interval 1.07 to 2.01) compared with those without AF. However, there was no evidence that the impact of AF on MI survival changed over time or differed over time by sex, race, or MI classification (all p values >0.10). In conclusion, co-occurrence of AF in MI slightly increased between 1987 and 2009. The adverse impact of AF on survival in the setting of MI was consistent throughout. In the setting of MI, co-occurrence of AF should be viewed as a critical clinical event, and treatment needs unique to this population should be explored further. Copyright © 2014 Elsevier Inc. All rights reserved.

Dominant frequency increase rate predicts transition from paroxysmal to long-term persistent atrial fibrillation.

PubMed

Martins, Raphael P; Kaur, Kuljeet; Hwang, Elliot; Ramirez, Rafael J; Willis, B Cicero; Filgueiras-Rama, David; Ennis, Steven R; Takemoto, Yoshio; Ponce-Balbuena, Daniela; Zarzoso, Manuel; O'Connell, Ryan P; Musa, Hassan; Guerrero-Serna, Guadalupe; Avula, Uma Mahesh R; Swartz, Michael F; Bhushal, Sandesh; Deo, Makarand; Pandit, Sandeep V; Berenfeld, Omer; Jalife, José

2014-04-08

Little is known about the mechanisms underlying the transition from paroxysmal to persistent atrial fibrillation (AF). In an ovine model of long-standing persistent AF we tested the hypothesis that the rate of electric and structural remodeling, assessed by dominant frequency (DF) changes, determines the time at which AF becomes persistent. Self-sustained AF was induced by atrial tachypacing. Seven sheep were euthanized 11.5±2.3 days after the transition to persistent AF and without reversal to sinus rhythm; 7 sheep were euthanized after 341.3±16.7 days of long-standing persistent AF. Seven sham-operated animals were in sinus rhythm for 1 year. DF was monitored continuously in each group. Real-time polymerase chain reaction, Western blotting, patch clamping, and histological analyses were used to determine the changes in functional ion channel expression and structural remodeling. Atrial dilatation, mitral valve regurgitation, myocyte hypertrophy, and atrial fibrosis occurred progressively and became statistically significant after the transition to persistent AF, with no evidence for left ventricular dysfunction. DF increased progressively during the paroxysmal-to-persistent AF transition and stabilized when AF became persistent. Importantly, the rate of DF increase correlated strongly with the time to persistent AF. Significant action potential duration abbreviation, secondary to functional ion channel protein expression changes (CaV1.2, NaV1.5, and KV4.2 decrease; Kir2.3 increase), was already present at the transition and persisted for 1 year of follow up. In the sheep model of long-standing persistent AF, the rate of DF increase predicts the time at which AF stabilizes and becomes persistent, reflecting changes in action potential duration and densities of sodium, L-type calcium, and inward rectifier currents.

Socioeconomic status and the development of atrial fibrillation in Hispanics, African Americans and non-Hispanic whites.

PubMed

Shulman, Eric; Kargoli, Faraj; Aagaard, Philip; Hoch, Ethan; Di Biase, Luigi; Fisher, John; Gross, Jay; Kim, Soo; Ferrick, Kevin J; Krumerman, Andrew

2017-09-01

Atrial fibrillation (AF) is the most common arrhythmia and is associated with significant morbidity and mortality. Despite having a higher burden of traditional AF risk factors, African American and Hispanic minorities have a lower incidence of AF when compared to non-Hispanic whites, referred to as the "racial paradox." Lower SES among Hispanics and African Americans may help to explain the lower incidence rates of AF compared to non-Hispanic whites. An electrocardiogram/electronic medical records database in New York State was interrogated for individuals free of AF for development of subsequent AF from 2000 to 2013. SES was assessed per zip code via a composite of 6 measures Z-scored to the New York State average. SES was reclassified into decile groups. Cox regression analysis controlling for all baseline differences was used to estimate the independent predictive ability of SES for AF. We identified 48 631 persons (43% Hispanic, 37% African Americans, and 20% non-Hispanic white; mean age 59 years; mean follow-up of 3.2 years) of which 4556 AF cases occurred. Hispanics and African Americans had lower AF risk than whites in all SES deciles (P < 0.001 by log-rank test). Higher SES was borderline associated with lower AF risk (hazard ratio: 0.990, 95% confidence interval: 0.980-1.001, P = 0.061). P trend analysis was not significant by any race/ethnic group by SES deciles for AF. Our study suggests that non-Hispanic whites were at higher risk for AF compared to nonwhites, and this was independent of SES. © 2017 Wiley Periodicals, Inc.

The Long and Short Term Impact of Elevated Body Mass Index on Risk of New Atrial Fibrillation in the Women’s Health Study

PubMed Central

Tedrow, Usha B; Conen, David; Ridker, Paul M; Cook, Nancy R; Koplan, Bruce A; Manson, JoAnn E; Buring, Julie E; Albert, Christine M

2010-01-01

Objectives To characterize the relationship between changes in body mass index (BMI) and incident atrial fibrillation (AF) in a large cohort of women. Background Obesity and AF are increasing public health problems. The importance of dynamic obesity-associated AF risk is uncertain, and mediators are not well characterized. Methods Cases of AF were confirmed by medical record review in 34,309 participants in the Women’s Health Study. Baseline and updated measures of BMI were obtained from periodic questionnaires. Results Over 12.9 +/− 1.9 years of follow-up, 834 AF events were confirmed. BMI was linearly associated with AF risk, with a 4.7% (95% CI 3.4, 6.1, p<0.0001) increase in risk with each kg/m2. Adjustment for inflammatory markers minimally attenuated this risk. When updated measures of BMI were utilized to estimate dynamic risk, overweight (HR 1.22 95%CI 1.02, 1.45, p=0.03) and obesity (HR 1.65 95%CI 1.36, 2.00, p<0.0001) were associated with adjusted short term elevations in AF risk. Participants becoming obese during the first 60 months had a 41% adjusted increase in risk of developing AF (p=0.02) compared to those maintaining BMI <30 kg/m2. The prevalence of overweight and obesity increased over time. The adjusted proportion of incident AF attributable to short term elevations in BMI was substantial (18.3%). Conclusions In this population of apparently healthy women, BMI was associated with short and long term elevations in AF risk, accounting for a large proportion of incident AF independent of traditional risk factors. A strategy of weight control may reduce the increasing incidence of AF. PMID:20488302

The impact of B-type natriuretic peptide levels on the suppression of accompanying atrial fibrillation in Wolff-Parkinson-White syndrome patients after accessory pathway ablation.

PubMed

Kawabata, Mihoko; Goya, Masahiko; Takagi, Takamitsu; Yamashita, Shu; Iwai, Shinsuke; Suzuki, Masahito; Takamiya, Tomomasa; Nakamura, Tomofumi; Hayashi, Tatsuya; Yagishita, Atsuhiko; Sasaki, Takeshi; Takahashi, Yoshihide; Ono, Yuhichi; Hachiya, Hitoshi; Yamauchi, Yasuteru; Otomo, Kenichiro; Nitta, Junichi; Okishige, Kaoru; Nishizaki, Mitsuhiro; Iesaka, Yoshito; Isobe, Mitsuaki; Hirao, Kenzo

2016-12-01

Atrial fibrillation (AF) often coexists with Wolff-Parkinson-White (WPW) syndrome. We compared the efficacy of Kent bundle ablation alone and additional AF ablation on accompanying AF, and examined which patients would still have a risk of AF after successful Kent bundle ablation. This retrospective multicenter study included 96 patients (56±15 years, 72 male) with WPW syndrome and AF undergoing Kent bundle ablation. Some patients underwent simultaneous pulmonary vein isolation (PVI) for AF. The incidence of post-procedural AF was examined. Sixty-four patients underwent only Kent bundle ablation (Kent-only group) and 32 also underwent PVI (+PVI group). There was no significant difference in the basic patient characteristics between the groups. Additional PVI did not improve the freedom from residual AF compared to Kent bundle ablation alone (p=0.53). In the Kent-only group, AF episodes remained in 25.0% during the follow-up (709 days). A univariate analysis showed that age ≥60 years, left atrial dimension ≥38mm, B-type natriuretic peptide (BNP) ≥40pg/ml, and concomitant hypertension were predictive factors for residual AF. However, in the multivariate analysis, only BNP ≥40pg/ml remained as an independent predictive factor (HR=17.1 and CI: 2.3-128.2; p=0.006). Among patients with WPW syndrome and AF, Kent bundle ablation alone may have a sufficient clinical impact of preventing recurrence of AF in select patients. Screening the BNP level would help decide the strategy to manage those patients. Copyright © 2016 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

[AFNET. A translational research network develops into an academic research organization].

PubMed

Kirchhof, Paulus; Goette, Andreas; Näbauer, Michael; Schotten, Ulrich

2016-04-01

"The whole is greater than the sum of its parts" (Aristotle).Atrial fibrillation (AF) is the most common sustained arrhythmia and affects 1-2 % of the population in developed countries, especially the elderly. We expect that the prevalence of AF will double in the next few decades. The last decades have seen important improvements in the management of atrial fibrillation, but many questions remain regarding the optimal diagnosis and management of the condition. The German Atrial Fibrillation NETwork (AFNET) was one of three cardiovascular competence networks in medicine funded by the German Ministry of Education and Research between 2003-2014. AFNET has contributed to the understanding of atrial fibrillation, and AFNET-led studies have led to improved clinical practices and practice guidelines in Germany and in Europe. This work has been expanded and is continuing in the AFNET association (AFNET e. V.). The AFNET association, founded in 2010 and continuing to this day, has developed into a small but fully formed academic research organisation that conducts investigator-initiated clinical trials as the responsible sponsor in Germany, Europe, and beyond. The AFNET association currently cooperates with EHRA (The European Heart Rhythm Association), ESC (The European Society of Cardiology) and DZHK (The German Centre for Cardiovascular Research) and receives funding from the European Union to generate evidence that can in the future lead to better prevention and management of AF.

Physical activity, obesity, weight change, and risk of atrial fibrillation: the Atherosclerosis Risk in Communities study.

PubMed

Huxley, Rachel R; Misialek, Jeffrey R; Agarwal, Sunil K; Loehr, Laura R; Soliman, Elsayed Z; Chen, Lin Y; Alonso, Alvaro

2014-08-01

Physical activity (PA) has previously been suggested to attenuate the risk of atrial fibrillation (AF) conferred by excess body weight and weight gain. We prospectively examined the relationship between body size, weight change, and level of PA in a biracial cohort of middle-aged men and women. Baseline characteristics on risk factor levels were obtained on 14 219 participants from the Atherosclerosis Risk in Communities Study. AF incidence was ascertained from 1987 to 2009. Adjusted Cox proportional hazards models were used to estimate the associations between body mass index, waist circumference, relative weight change, and PA level with incident AF. During follow-up, there were 1775 cases of incident AF. Body mass index and waist circumference were positively associated with AF as was weight loss/gain of >5% initial body weight. An ideal level of PA had a small protective effect on AF risk and partially attenuated the risk of AF associated with excess weight in men but not women: compared with men with a normal body mass index, the risk of AF in obese men with an ideal, intermediate, and poor level of PA at baseline was increased by 37%, 129%, and 156% (Pinteraction=0.04). During follow-up, PA did not modify the association between weight gain and risk of AF. Obesity and extreme weight change are risk factors for incident AF, whereas being physically active is associated with a small reduction in risk. In men only, being physically active offset some, but not all, of the risk incurred with excess body weight. © 2014 American Heart Association, Inc.

Thinking outside the Box: Rotor Modulation in the Treatment of Atrial Fibrillation.

PubMed

Sehra, Ruchir; Narayan, Sanjiv M; Hummel, John

2013-01-01

Ablation for atrial fibrillation (AF) is an important and exciting therapy whose results remain suboptimal. Although most clinical trials show that ablation eliminates AF more effectively than medications, it is disappointing that the continued single procedural success remains ≈50% despite the substantial advances that have taken place in imaging, catheter positioning and energy delivery. Focal impulse and rotor modulation (FIRM), on the other hand, offers the opportunity to precisely define and then ablate patient-specific sustaining mechanisms for AF, rather than trying to eliminate all possible AF triggers. For over a decade, electrophysiologists have described cases in which AF terminates after only limited ablation - usually that cannot be explained by 'random' meandering wavelets. Indeed, recent studies from several laboratories show that all forms of clinical AF are typically 'driven' by stable electrical rotors and focal sources, not by multiple meandering waves. FIRM mapping enables an operator to place a catheter at typically 1-3 predicted sites in the atria, and with <5-10 minutes of RF ablation, terminate AF and potentially render it non-inducible. Several independent laboratories have now shown that such FIRM ablation alone can terminate or substantially slow AF in >80% of patients with persistent and paroxysmal AF and increase the single procedure rate of AF elimination from 50% with PV isolation alone to >80%. Ongoing studies hint that FIRM only ablation, enabling ablation times in the range observed for typical atrial flutter, may also achieve these high success rates without subsequent trigger ablation. This review summarizes the current state-of-the-art on FIRM mapping and ablation.

High intensity focused ultrasound ablation for atrial fibrillation: results from the National Spanish Registry.

PubMed

Reyes, Guillermo; Ruyra, Xavier; Valderrama, Francisco; Jimenez, Antonio; Duran, Dario; Perez, Enrique; Daroca, Tomas; Moya, Javier; Ramirez, Ulises; Aldamiz, Gonzalo

2016-10-01

A National Spanish Registry to compile all patients treated with high intensity focused ultrasound (HIFU) energy for atrial fibrillation (AF) was created to evaluate the safety and efficacy of AF surgical ablation. A national Spanish registry was created, and ten hospitals using HIFU to ablate AF joined it. A total of 412 patients undergoing cardiac surgery between 2006 and February 2013 were included. AF was divided between paroxysmal AF (33%) and persistent AF (67%) with a mean AF duration of 29.3±108.2 months. Mean left atrial diameter was 51.2±6.5 mm. Mean underlying heart disease were aortic valve disease (49.3%), ischemic disease (25.2%) and mitral disease (33.2%) Clinical follow-up of patients and a 6 months postoperative echocardiogram were performed in all patients. A pacemaker implantation was needed in 4.9% of patients with a perioperative stroke in 2.5%. Rhythm at discharge from hospital was sinus rhythm in 58%, AF in 35.9% and atrial flutter in 0.8% of patients. Sinus rhythm restoration at 6, 12, 24 and 36 months follow-up was achieved in 66.1%, 63.8%, 63.9% and 45.9% of patients respectively. Multivariate analysis showed paroxysmal AF and sinus rhythm restoration in the operating theatre as factors related to sinus rhythm long term restoration. The Spanish national registry showed an efficacy of AF ablation with the HIFU Epicor system of 66.1%, 63.8%, 63.9% and 45.9% at 6, 12, 24 and 36 months follow-up. There were no device-related complications.

Interatrial septum versus right atrial appendage pacing for prevention of atrial fibrillation : A meta-analysis of randomized controlled trials.

PubMed

Zhang, L; Jiang, H; Wang, W; Bai, J; Liang, Y; Su, Y; Ge, J

2017-07-28

Interatrial septum (IAS) pacing seems to be a promising strategy for the prevention of atrial fibrillation (AF); however, studies have yielded conflicting results. This meta-analysis was to compare IAS with right atrial appendage (RAA) pacing on the prevention of postpacing AF occurrence. Pubmed, MEDLINE, EMBASE and Web of Science databases were searched through October 2016 for randomized controlled trials comparing IAS with RAA pacing on the prevention of AF. Data concerning study design, patient characteristics and outcomes were extracted. Risk ratio (RR), weighted mean differences (WMD) or standardized mean differences (SMD) were calculated using fixed or random effects models. A total of 12 trials involving 1146 patients with dual-chamber pacing were included. Although IAS was superior to RAA pacing in terms of reducing the number of AF episodes (SMD = -0.29, P = 0.05), AF burden (SMD = -0.41, P = 0.008) and P -wave duration (WMD = -34.45 ms, P < 0.0001), neither permanent AF occurrence (RR = 0.94, P = 0.58) nor recurrences of AF (RR = 0.88, P = 0.36) were reduced by IAS pacing. Nevertheless, no differences were observed concerning all-cause death (RR = 1.04, P = 0.88), procedure-related events (RR = 1.17, P = 0.69) and pacing parameters between IAS and RAA pacing in the follow-up period. IAS pacing is safe and as well tolerated as RAA pacing. Although IAS pacing may fail to prevent permanent AF occurrence and recurrences of AF, it is able to not only improve interatrial conduction, but also reduce AF burden.

Serum and dietary magnesium and incidence of atrial fibrillation in whites and in African Americans--Atherosclerosis Risk in Communities (ARIC) study.

PubMed

Misialek, Jeffrey R; Lopez, Faye L; Lutsey, Pamela L; Huxley, Rachel R; Peacock, James M; Chen, Lin Y; Soliman, Elsayed Z; Agarwal, Sunil K; Alonso, Alvaro

2013-01-01

Low serum magnesium (Mg) has been associated with an increased risk of cardiovascular disease (CVD), including ventricular arrhythmias, but the association between serum or dietary Mg and atrial fibrillation (AF) has not been investigated. A total of 14,290 men and women (75% white; 53% female; mean age, 54 years) free of AF at baseline participating in the Atherosclerosis Risk in Communities study in the United States, were studied. Incident AF cases through 2009 were ascertained from electrocardiograms, hospital discharge codes, and death certificates. Multivariate Cox proportional hazards regression was used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for AF associated with serum and dietary Mg quintiles. Over a median follow-up time of 20.6 years, 1,755 incident AF cases were identified. In multivariate models, lower serum Mg was associated with higher AF risk: compared to individuals in the middle quintile (≥ 0.80-0.83 mmol/L), the HR (95% CI) of AF in quintiles 1, 2, 4, and 5 were 1.34 (1.16-1.54), 0.99 (0.85-1.16), 1.04 (0.90-1.22), and 1.06 (0.91-1.23), respectively. There was no evidence of significant interactions between serum Mg and sex or race. No association between dietary Mg and AF risk was observed. Lower serum Mg was associated with a higher AF risk, and this association was not different between whites and African Americans. Dietary Mg was not associated with AF risk.

Chronotropic Incompetence and Risk of Atrial Fibrillation: The Henry Ford ExercIse Testing (FIT) Project.

PubMed

O'Neal, Wesley T; Qureshi, Waqas T; Blaha, Michael J; Dardari, Zeina A; Ehrman, Jonathan K; Brawner, Clinton A; Soliman, Elsayed Z; Al-Mallah, Mouaz H

2016-11-01

To examine the association between chronotropic incompetence and incident atrial fibrillation (AF). Patients with inadequate heart rate response during exercise may have abnormalities in sinus node function or autonomic tone that predispose to the development of AF. We examined the association between heart rate response and incident AF in 57,402 (mean age=54±13 years, 47% female, 64% white) patients free of baseline AF who underwent exercise-treadmill stress testing from the Henry Ford ExercIse Testing (FIT) Project. Age-predicted maximum heart rate (pMHR) values <85% and chronotropic index values <80% were used to define chronotropic incompetence. Cox regression, adjusting for demographics, cardiovascular risk factors, medications, coronary heart disease, heart failure, and metabolic equivalent of task achieved, was used to compute hazard ratios (HR) and 95% confidence intervals (CI) for the association between chronotropic incompetence and incident AF. Over a median follow-up of 5.0 years (25 th -75 th percentiles=2.6, 7.8), a total of 3,395 (5.9%) participants developed AF. pMHR values <85% were associated with an increased risk for AF development (HR=1.33, 95%CI=1.22, 1.44). Chronotropic index values <80% also were associated with an increased risk of AF (HR=1.28, 95%CI=1.19, 1.38). The associations of pMHR and chronotropic index with AF remained significant with varying cut-off points to define chronotropic incompetence. Our analysis suggests that patients with inadequate heart rate response during exercise have an increased risk for developing AF.

Are left ventricular ejection fraction and left atrial diameter related to atrial fibrillation recurrence after catheter ablation?

PubMed Central

Jin, Xiao; Pan, Jianke; Wu, Huanlin; Xu, Danping

2018-01-01

Abstract Atrial fibrillation (AF), the most common form of arrhythmia, is associated with the prevalence of many common cardiovascular and cerebrovascular diseases. Catheter ablation is considered the first-line therapy for AF; however, AF recurrence is very common after catheter ablation. Studies have been performed to analyze the factors associated with AF recurrence, but none have reached a consistent conclusion on whether left ventricular ejection fraction (LVEF) and left atrial diameter (LA diameter) affect AF recurrence after catheter ablation. The databases PubMed, Embase, and the Cochrane Library were used to search for relevant studies up to September 2017. RevMan 5.3.5 software provided by the Cochrane Collaboration Network was used to conduct this meta-analysis. Thirteen studies involving 2825 patients were included in this meta-analysis. Overall, the results revealed that elevated LA diameter values were significantly associated with AF recurrence in patients after catheter ablation (MD = 2.19, 95% CI: 1.63–2.75, P < .001), while baseline LVEF levels were not significantly positively associated with AF recurrence in patients after catheter ablation (MD = −0.91, 95% CI: −1.18 to 1.67, P = .14). Overall, elevated LA diameter may be associated with AF recurrence after catheter ablation; however, there was no direct relationship between LVEF values and AF recurrence after catheter ablation when baseline LVEF values are normal or mildly decreased. Besides, because of publication bias, further studies should be performed to explore the mechanisms underlying AF recurrence. PMID:29768386

Isolation of canine coronary sinus musculature from the atria by radiofrequency catheter ablation prevents induction of atrial fibrillation.

PubMed

Morita, Hiroshi; Zipes, Douglas P; Morita, Shiho T; Wu, Jiashin

2014-12-01

The junction between the coronary sinus (CS) musculature and both atria contributes to initiation of atrial tachyarrhythmias. The current study investigated the effects of CS isolation from the atria by radiofrequency catheter ablation on the induction and maintenance of atrial fibrillation (AF). Using an optical mapping system, we mapped action potentials at 256 surface sites in 17 isolated and arterially perfused canine atrial tissues containing the entire musculature of the CS, right atrial septum, posterior left atrium, left inferior pulmonary vein, and vein of Marshal. Rapid pacing from each site before and after addition of acetylcholine (0.5 μmol/L) was applied to induce AF. Epicardial radiofrequency catheter ablation at CS-atrial junctions isolated the CS from the atria. Rapid pacing induced sustained AF in all tissues after acetylcholine. Microreentry within the CS drove AF in 88% of preparations. Reentries associated with the vein of Marshall (29%), CS-atrial junctions (53%), right atrium (65%), and pulmonary vein (76%) (frequently with 2-4 simultaneous circuits) were additional drivers of AF. Radiofrequency catheter ablation eliminated AF in 13 tissues before acetylcholine (P<0.01) and in 5 tissues after acetylcholine. Radiofrequency catheter ablation also abbreviated the duration of AF in 12 tissues (P<0.01). CS and its musculature developed unstable reentry and AF, which were prevented by isolation of CS musculature from atrial tissue. The results suggest that CS can be a substrate of recurrent AF in patients after pulmonary vein isolation and that CS isolation might help prevent recurrent AF. © 2014 American Heart Association, Inc.

Age-dependent prognostic significance of atrial fibrillation in outpatients with chronic heart failure: data from the Italian Network on Congestive Heart Failure Registry.

PubMed

Baldasseroni, Samuele; Orso, Francesco; Fabbri, Gianna; De Bernardi, Alberto; Cirrincione, Vincenzo; Gonzini, Lucio; Fumagalli, Stefano; Marchionni, Niccolò; Midi, Paolo; Maggioni, Aldo Pietro

2010-01-01

The role of atrial fibrillation (AF) in older patients with heart failure (HF) is controversial because many variables seem to influence their outcome. We investigated the predictivity of AF in 3 age groups of outpatients with HF. We analyzed 8,178 outpatients enrolled in the Italian Network on Congestive Heart Failure Registry with HF diagnosed according to the European Society of Cardiology criteria. A trained cardiologist established the diagnosis of AF and HF at the entry visit at each center. We stratified the population into 3 age groups, as follows: group A, < or =65 years; group B, 66-75 years, and group C, >75 years. Group A was composed of 4,261 patients, 683 with AF (16.0%); in group B there were 2,651 patients, 638 with AF (24.1%), and group C was composed of 1,266 patients, 412 with AF (32.5%). The 1-year mortality rate was higher in AF patients in all groups. In a multivariate model, AF remained an independent risk factor for death in groups A and B, but not in group C [group A: hazard ratio (HR) 1.42, 95% confidence interval (CI) 1.10-1.81; group B: HR 1.29, 95% CI 1.00-1.67; group C: HR 1.05, 95% CI 0.78-1.43]. The prevalence of AF increased with age and was associated with a higher mortality rate. However, AF independently predicted all-cause mortality only in patients aged < or =75 years. Copyright 2010 S. Karger AG, Basel.

Clinical, Echocardiographic, and Electrocardiographic Predictors of Persistent Atrial Fibrillation after Dual-Chamber Pacemaker Implantation: An Integrated Scoring Model Approach.

PubMed

Cho, Min Soo; Kim, Jun; Kim, Ju Hyeon; Kim, Minsu; Lee, Ji Hyun; Hwang, You Mi; Jo, Uk; Nam, Gi-Byoung; Choi, Kee-Joon; Kim, You-Ho

2016-01-01

Persistent atrial fibrillation (PeAF) predictors after dual-chamber pacemaker (PM) implantation remain unclear. We sought to determine these predictors and establish an integrated scoring model. Data were retrospectively reviewed for 649 patients (63.8 ± 12.3 years, 48.6% male, mean CHA2DS2-VASC score 2.7 ± 2.0) undergoing dual-chamber PM implantation. PeAF was defined as documented AF on two consecutive electrocardiograms acquired ≥7 days apart. During a 7.1-year median follow-up (interquartile range 4.5-10.1 years), 67 (10.3%) patients had PeAF. Multivariable analysis showed the following independent predictors of future PeAF: ischemic stroke or transient ischemic accident history (hazard ratio [HR] 2.03, 95% confidence interval [CI] 1.03-3.50, p = 0.040), atrial fibrillation/flutter history (HR 1.80, 95% CI 1.01-3.20, p = 0.046), sinus node disease (HR 2.24, 95% CI 1.16-4.35, p = 0.016), left atrial enlargement (>45 mm, HR 2.14, 95% CI 1.26-3.63, p = 0.005), and time in automatic mode switching >1% at first follow-up interrogation (HR 2.58, 95% CI 1.51-4.42, p < 0.001). An integrated scoring model combining these predictors showed good discrimination performance at the seven-year follow-up. (C-statistic 0.716, 95% CI 0.629-0.802, p < 0.001). Significantly greater seven-year PeAF incidences were seen in patients with higher scores (2-5) than in those with lower scores (0-1) (22.8% ± 3.8% vs. 5.3% ± 1.7%, p < 0.001). In conclusion, an integrated scoring model combining clinical, echocardiographic, and electrocardiographic characteristics is useful for predicting future PeAF in patients with a dual-chamber PM.

Clinical, Echocardiographic, and Electrocardiographic Predictors of Persistent Atrial Fibrillation after Dual-Chamber Pacemaker Implantation: An Integrated Scoring Model Approach

PubMed Central

Cho, Min Soo; Kim, Ju Hyeon; Kim, Minsu; Lee, Ji Hyun; Hwang, You Mi; Jo, Uk; Nam, Gi-Byoung; Choi, Kee-Joon; Kim, You-Ho

2016-01-01

Persistent atrial fibrillation (PeAF) predictors after dual-chamber pacemaker (PM) implantation remain unclear. We sought to determine these predictors and establish an integrated scoring model. Data were retrospectively reviewed for 649 patients (63.8 ± 12.3 years, 48.6% male, mean CHA2DS2–VASC score 2.7 ± 2.0) undergoing dual-chamber PM implantation. PeAF was defined as documented AF on two consecutive electrocardiograms acquired ≥7 days apart. During a 7.1-year median follow-up (interquartile range 4.5–10.1 years), 67 (10.3%) patients had PeAF. Multivariable analysis showed the following independent predictors of future PeAF: ischemic stroke or transient ischemic accident history (hazard ratio [HR] 2.03, 95% confidence interval [CI] 1.03–3.50, p = 0.040), atrial fibrillation/flutter history (HR 1.80, 95% CI 1.01–3.20, p = 0.046), sinus node disease (HR 2.24, 95% CI 1.16–4.35, p = 0.016), left atrial enlargement (>45 mm, HR 2.14, 95% CI 1.26–3.63, p = 0.005), and time in automatic mode switching >1% at first follow-up interrogation (HR 2.58, 95% CI 1.51–4.42, p < 0.001). An integrated scoring model combining these predictors showed good discrimination performance at the seven-year follow-up. (C-statistic 0.716, 95% CI 0.629–0.802, p < 0.001). Significantly greater seven-year PeAF incidences were seen in patients with higher scores (2–5) than in those with lower scores (0–1) (22.8% ± 3.8% vs. 5.3% ± 1.7%, p < 0.001). In conclusion, an integrated scoring model combining clinical, echocardiographic, and electrocardiographic characteristics is useful for predicting future PeAF in patients with a dual-chamber PM. PMID:27479069

Clinical Implications of Technological Advances in Screening for Atrial Fibrillation.

PubMed

Singh, Nikhil; Chun, Sung; Hadley, David; Froelicher, Victor

The incidence of atrial fibrillation (AF) continues to increase worldwide as people live longer. AF is the leading cause of stroke among patients older than 75 years and is responsible for at least 15% of all strokes. Industry has responded to this problem with a plethora of monitoring devices. These include single lead ECG adhesive sensors, implantable loop recorders, smartphone attachments and wearables. This review will concentrate on clinical studies using these technologies. There are wearables including watches and watch-like devices that will be mentioned but these have not been validated for clinical use. This review will begin with a background regarding screening for AF and at the end present findings from Cardiac Implantable devices that could influence use of the new mobile health technologies. Copyright © 2018 Elsevier Inc. All rights reserved.

Anti-arrhythmic strategies for atrial fibrillation

PubMed Central

Grandi, Eleonora; Maleckar, Mary M.

2016-01-01

Atrial fibrillation (AF), the most common cardiac arrhythmia, is associated with increased risk of cerebrovascular stroke, and with several other pathologies, including heart failure. Current therapies for AF are targeted at reducing risk of stroke (anticoagulation) and tachycardia-induced cardiomyopathy (rate or rhythm control). Rate control, typically achieved by atrioventricular nodal blocking drugs, is often insufficient to alleviate symptoms. Rhythm control approaches include antiarrhythmic drugs, electrical cardioversion, and ablation strategies. Here, we offer several examples of how computational modeling can provide a quantitative framework for integrating multi scale data to: (a) gain insight into multi-scale mechanisms of AF; (b) identify and test pharmacological and electrical therapy and interventions; and (c) support clinical decisions. We review how modeling approaches have evolved and contributed to the research pipeline and preclinical development and discuss future directions and challenges in the field. PMID:27612549

European Society of Cardiology smartphone and tablet applications for patients with atrial fibrillation and their health care providers

PubMed Central

Kotecha, Dipak; Chua, Winnie W L; Fabritz, Larissa; Hendriks, Jeroen; Casadei, Barbara; Schotten, Ulrich; Vardas, Panos; Heidbuchel, Hein; Dean, Veronica; Kirchhof, Paulus

2018-01-01

Abstract We are in the midst of a digital revolution in health care, although the application of new and useful technology in routine clinical practice is variable. The Characterizing Atrial fibrillation by Translating its Causes into Health Modifiers in the Elderly (CATCH ME) Consortium, in collaboration with the European Society of Cardiology (ESC), has funded the creation of two applications (apps) in atrial fibrillation (AF) for use in smartphones and tablets. The patient app aims to enhance patient education, improve communication between patients and health care professionals, and encourage active patient involvement in the management of their condition. The health care professional app is designed as an interactive management tool incorporating the new ESC Practice Guidelines on AF and supported by the European Heart Rhythm Association (EHRA), with the aim of improving best practice approaches for the care of patients with AF. Both stand-alone apps are now freely available for Android and iOS devices though the Google Play, Amazon, and Apple stores. In this article, we outline the rationale for the design and implementation of these apps. Our objective is to demonstrate the value of integrating novel digital technology into clinical practice, with the potential for patient engagement, optimization of pharmacological and interventional therapy in AF, and ultimately to improve patient outcomes. PMID:29040548

Effect of interconnection between cervical vagus trunk, epicardial fat pad on sinus node function, and atrial fibrillation.

PubMed

Zhou, Qina; Zhang, Ling; Wang, Kun; Xu, Xiaoxia; Ji, Meng; Zhang, Feng; Wang, Hongli; Hou, Yuemei

2014-03-01

The epicardial fat pad (FP) integrates the autonomic innervation between the extrinsic and intrinsic cardiac autonomic nervous system and affects atrial electrophysiology and pathophysiology. Eighteen dogs were divided into two groups: sequential ablation of sinoatrial node FP (SAN-FP) and atrioventricular node FP (AVN-FP). Sinus rate (SR), atrial fibrillation (AF) inducibility, and effective refractory period (ERP) changes during electrical stimulation of the vagus trunk were detected before and after ablation. In the SAN-FP group, the SR slowing, increasing AF inducibility, and ERP shortening that induced by vagus trunk stimulation were significantly attenuated by isolated SAN-FP ablation, compared with the same group prior to ablation (all P < 0.05). Subsequent AVN-FP ablation following SAN-FP ablation almost cannot produce further attenuation during vagus trunk stimulation, compared with isolated SAN-FP ablation (P > 0.05). In the AVN-FP group, SR slowing, increasing AF inducibility, and ERP shortening that induced by vagus trunk stimulation were completely eliminated by isolated AVN-FP ablation, compared with the same group prior to ablation (all P < 0.05). Subsequent SAN-FP ablation following AVN-FP ablation produced no further attenuation, compared with isolated AVN-FP ablation (P > 0.05). A neural pathway from the cervical vagus trunk to the sinus node and atrium runs through the SAN-FP, but eventually converges at the AVN-FP and also suggested that the AVN-FP serves as an "integration center" for the SAN-FP to modulate sinus node function. The AVN-FP may play a more critical role in the initiation and maintenance of AF. ©2013 First Affilated Hospital of Xingiang Medical University Pacing and Clinical Electrophysiology ©2013 Wiley Periodicals, Inc.