Boriani, Giuseppe; Laroche, Cecile; Diemberger, Igor; Fantecchi, Elisa; Popescu, Mircea Ioachim; Rasmussen, Lars Hvilsted; Sinagra, Gianfranco; Petrescu, Lucian; Tavazzi, Luigi; Maggioni, Aldo P; Lip, Gregory Y H
Atrial fibrillation is often asymptomatic, but outcomes require further characterization. The study objective was to investigate the clinical presentation, management, and outcomes in asymptomatic and symptomatic patients with atrial fibrillation who were prospectively enrolled in the EurObservational Research Programme - Atrial Fibrillation (EORP-AF) Pilot General Registry. A total of 3119 patients were enrolled, and 1237 (39.7%) were asymptomatic (European Heart Rhythm Association [EHRA] score I). Among symptomatic patients, 963 (51.2%) had mild symptoms (EHRA score II) and 919 (48.8%) had severe or disabling symptoms (EHRA III-IV). Permanent atrial fibrillation was 3-fold more common in asymptomatic patients than in symptomatic patients. On multivariate analysis, male gender (odds ratio [OR], 1.630; 95% confidence interval [CI], 1.384-1.921), older age (OR, 1.019; 95% CI, 1.012-1.026), previous myocardial infarction (OR, 1.681; 95% CI, 1.350-2.093), and limited physical activity (OR, 1.757; 95% CI, 1.495-2.064) were associated significantly with asymptomatic (EHRA I) atrial fibrillation. Fully asymptomatic atrial fibrillation (absence of current and previous symptoms) was present in 520 patients (16.7%) and was associated independently with male gender, age, and previous myocardial infarction. Appropriate guideline-based prescription of oral anticoagulants was lower in these patients, and aspirin was prescribed more frequently. Mortality at 1 year was more than 2-fold higher in asymptomatic patients compared with symptomatic patients (9.4% vs 4.2%, P < .0001) and was associated independently with older age and comorbidities, including chronic kidney disease and chronic heart failure. Asymptomatic atrial fibrillation is common in daily cardiology practice and is associated with elderly age, more comorbidities, and high thromboembolic risks. A higher 1-year mortality was found in asymptomatic patients compared with symptomatic patients. Copyright © 2015 Elsevier
Atrial fibrillation is an arrhythmia characterized by no-coordinated atrial contraction that results in an inefficient atrial systole. The clinical classification of atrial fibrillation includes: ocassional, paroxysmal, persistent, and permanent. Multiple mechanisms have been described and accounts for a single ECG manifestation. Treatment should be individualized and has to considered several aspects including age, associated heart disease, and symptoms. Treatment strategies are: rhythm control, rate control, and thromboprophylaxis.
... information about the heart's electrical system and detailed animations, go to the Diseases and Conditions Index How ... can't restore a normal heart rhythm. The animation below shows atrial fibrillation. Click the "start" button ...
This issue provides a clinical overview of atrial fibrillation, focusing on diagnosis, treatment, and practice improvement. The content of In the Clinic is drawn from the clinical information and education resources of the American College of Physicians (ACP), including MKSAP (Medical Knowledge and Self-Assessment Program). Annals of Internal Medicine editors develop In the Clinic in collaboration with the ACP's Medical Education and Publishing divisions and with the assistance of additional science writers and physician writers.
Munger, Thomas M.; Wu, Li-Qun; Shen, Win K.
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
Saito, Tsukasa; Kawamura, Yuichiro; Tanabe, Yasuko; Asanome, Asuka; Takahashi, Kae; Sawada, Jun; Katayama, Takayuki; Sato, Nobuyuki; Aizawa, Hitoshi; Hasebe, Naoyuki
Atrial fibrillation (AF) is a cardiac arrhythmia that does not infrequently induce ischemic strokes; however, little research has been reported on focal cerebral microangiopathic lesions in patients with AF. Recently cerebral microbleeds (CMBs) have been noticed for their potential implication in cerebral small vessel disease. Therefore, we had 2 goals in the present study: (1) to compare the prevalence of CMBs in patients with AF with that in patients without AF, and (2) to prove that CMBs could be a clinical predictive factor for the development of future cerebral microangiopathy in patients with AF without a history of symptomatic cerebral infarction in a prospective manner. We performed yearly brain magnetic resonance imaging (MRI) assessments for a maximum of 5 years in 131 patients with AF and 112 control patients. Seventy-seven patients with AF underwent more than 3 yearly MRI scans. The Kaplan-Meier curve showed that the development of an asymptomatic cerebral infarction (ACI) was associated with the baseline presence of a CMB (P=.004). A multivariate Cox regression analysis revealed that the CMBs at baseline were significantly associated with an increment in not only the occurrence of ACIs (hazard ratio [HR], 5.414; 95% confidence interval [CI], 1.03-28.43; P=.046) but also in the consecutive development of CMBs (HR, 6.274; 95% CI, 1.43-27.56; P=.015). Patients with AF had a significantly higher prevalence of CMBs. The presence of CMBs in the baseline MRI may predict the consequent onset of an ACI and increase in CMBs in patients with AF. Copyright © 2014 National Stroke Association. Published by Elsevier Inc. All rights reserved.
Auricular fibrillation - discharge; A-fib - discharge; AF - discharge; Afib - discharge ... been in the hospital because you have atrial fibrillation . This condition occurs when your heart beats faster ...
ANSWERS by heart Cardiovascular Conditions What Is Atrial Fibrillation? Your heart has a natural pacemaker, called the “ ... if the electric signals are normal. In atrial fibrillation (AFib), the heart’s two small upper chambers (atria) ...
... atrial fibrillation include: Alcohol use (especially binge drinking) Coronary artery disease Heart attack or heart bypass surgery Heart failure ... low. An ECG (a test that records the electrical activity of the heart) may show atrial fibrillation ...
Colín Lizalde, L J
Atrial fibrillation (AF) is the most common sustained arrhythmia. AF has now been exhaustively studied: more is known about its mechanism and research is moving towards new forms of treatment. For chronic AF, basically the control of ventricular rate and the brain protection are the main issues. It is well known that with the identification of high risk group for embolism, oral anticoagulation should be administered. Ventricular rate control can be achieved by using betablockers or calcium channel blockers, unless these are contraindicated for the elderly. Oral anticoagulation prevents the stroke. The main mechanism of AF is the re-entry of multiple wavelets, but now it is more frequently found on patients with focal AF. Therapies are employed to bring the patient to a sinusal rhythm as soon as possible with antiarryhthmics or electric cardioversion externally or internally. The internal procedure includes 1 to 15 J and the success rate is of 91% vs 67% in relation to the external one. The introduction of the catheter ablation has opened new frontiers for the treatment of AF, first as the ablate-and-pace technique and now trying to mimic the maze procedure or with the ablation of the focal tachycardia. The stimulation for prevention of AF under research, as well as the implantable dysfibrillation for selected patients. On going studies will show the possible benefit of this type of benefits.
Moukabary, Talal; Gonzalez, Mario D
Atrial fibrillation is a very common clinical problem with a high prevalence that is expected to rise over time because of increasing risk factors (eg, age, obesity, hypertension). This high prevalence is also associated with high cost, because atrial fibrillation represents about 1% of overall health care spending. The management of atrial fibrillation involves multiple facets: (1) management of underlying disease if present and the management of atrial fibrillation risk factors, (2) prevention of thromboembolism, (3) control of the ventricular rate during atrial fibrillation, and (4) restoration and maintenance of normal sinus rhythm.
Dalen, James E; Alpert, Joseph S
A new suspected cause of cryptic strokes is "silent atrial fibrillation." Pacemakers and other implanted devices allow continuous recording of cardiac rhythm for months or years. They have discovered that short periods of atrial fibrillation lasting minutes or hours are frequent and usually are asymptomatic. A meta-analysis of 50 studies involving more than 10,000 patients with a recent stroke found that 7.7% had new atrial fibrillation on their admitting electrocardiogram. In 3 weeks during and after hospitalization, another 16.9% were diagnosed. A total of 23.7% of these stroke patients had silent atrial fibrillation; that is, atrial fibrillation diagnosed after hospital admission. Silent atrial fibrillation is also frequent in patients with pacemakers who do not have a recent stroke. In a pooled analysis of 3 studies involving more than 10,000 patients monitored for 24 months, 43% had at least 1 day with atrial fibrillation lasting more than 5 minutes. Ten percent had atrial fibrillation lasting at least 12 hours. Despite the frequency of silent atrial fibrillation in these patients with multiple risk factors for stroke, the annual incidence of stroke was only 0.23%. When silent atrial fibrillation is detected in patients with recent cryptogenic stroke, anticoagulation is indicated. In patients without stroke, silent atrial fibrillation should lead to further monitoring for clinical atrial fibrillation rather than immediate anticoagulation, as some have advocated.
... from the NHLBI on Twitter. How Is Atrial Fibrillation Treated? Treatment for atrial fibrillation (AF) depends on ... much thyroid hormone). Who Needs Treatment for Atrial Fibrillation? People who have AF but don't have ...
... think you are pregnant If you notice red, dark brown or black urine or stools If you ... Fibrillation • Introduction • What is Atrial Fibrillation? • Why AFib Matters • Understand your Risk for AFib Children • Symptoms of ...
Kiuchi, Kunihiko; Okajima, Katsunori; Shimane, Akira; Kanda, Gaku; Yokoi, Kiminobu; Teranishi, Jin; Aoki, Kousuke; Chimura, Misato; Toba, Takayoshi; Oishi, Shogo; Sawada, Takahiro; Tsukishiro, Yasue; Onishi, Tetsuari; Kobayashi, Seiichi; Taniguchi, Yasuyo; Yamada, Shinichiro; Yasaka, Yoshinori; Kawai, Hiroya; Yoshida, Akihiro; Fukuzawa, Koji; Itoh, Mitsuaki; Imamura, Kimitake; Fujiwara, Ryudo; Suzuki, Atsushi; Nakanishi, Tomoyuki; Yamashita, Soichiro; Hirata, Ken-Ichi; Tada, Hiroshi; Yamasaki, Hiro; Naruse, Yoshihisa; Igarashi, Miyako; Aonuma, Kazutaka
Even with the use of a reduced energy setting (20-25 W), excessive transmural injury (ETI) following catheter ablation of atrial fibrillation (AF) is reported to develop in 10% of patients. However, the incidence of ETI depends on the pulmonary vein isolation (PVI) method and its esophageal temperature monitor setting. Data comparing the incidence of ETI following AF ablation with and without esophageal temperature monitoring (ETM) are still lacking. This study was comprised of 160 patients with AF (54% paroxysmal, mean: 24.0±2.9 kg/m(2)). Eighty patients underwent ablation accompanied by ETM. The primary endpoint was defined as the occurrence of ETI assessed by endoscopy within 5 d after the AF ablation. The secondary endpoint was defined as AF recurrence after a single procedure. If the esophageal temperature probe registered >39 °C, the radiofrequency (RF) application was stopped immediately. RF applications could be performed in a point-by-point manner for a maximum of 20 s and 20 W. ETI was defined as any injury that resulted from AF ablation, including esophageal injury or periesophageal nerve injury (peri-ENI). The incidence of esophageal injury was significantly lower in patients whose AF ablation included ETM compared with patients without ETM (0 [0%] vs. 6 [7.5%], p=0.028), but not the incidence of peri-ENI (2 [2.5%] vs. 3 [3.8%], p=1.0). AF recurrence 12 months after the procedure was similar between the groups (20 [25%] in the ETM group vs. 19 [24%] in the non-ETM group, p=1.00). Catheter ablation using ETM may reduce the incidence of esophageal injury without increasing the incidence of AF recurrence but not the incidence of peri-ENI.
Kiuchi, Kunihiko; Okajima, Katsunori; Shimane, Akira; Kanda, Gaku; Yokoi, Kiminobu; Teranishi, Jin; Aoki, Kousuke; Chimura, Misato; Toba, Takayoshi; Oishi, Shogo; Sawada, Takahiro; Tsukishiro, Yasue; Onishi, Tetsuari; Kobayashi, Seiichi; Taniguchi, Yasuyo; Yamada, Shinichiro; Yasaka, Yoshinori; Kawai, Hiroya; Yoshida, Akihiro; Fukuzawa, Koji; Itoh, Mitsuaki; Imamura, Kimitake; Fujiwara, Ryudo; Suzuki, Atsushi; Nakanishi, Tomoyuki; Yamashita, Soichiro; Hirata, Ken-ichi; Tada, Hiroshi; Yamasaki, Hiro; Naruse, Yoshihisa; Igarashi, Miyako; Aonuma, Kazutaka
Background Even with the use of a reduced energy setting (20–25 W), excessive transmural injury (ETI) following catheter ablation of atrial fibrillation (AF) is reported to develop in 10% of patients. However, the incidence of ETI depends on the pulmonary vein isolation (PVI) method and its esophageal temperature monitor setting. Data comparing the incidence of ETI following AF ablation with and without esophageal temperature monitoring (ETM) are still lacking. Methods This study was comprised of 160 patients with AF (54% paroxysmal, mean: 24.0±2.9 kg/m2). Eighty patients underwent ablation accompanied by ETM. The primary endpoint was defined as the occurrence of ETI assessed by endoscopy within 5 d after the AF ablation. The secondary endpoint was defined as AF recurrence after a single procedure. If the esophageal temperature probe registered >39 °C, the radiofrequency (RF) application was stopped immediately. RF applications could be performed in a point-by-point manner for a maximum of 20 s and 20 W. ETI was defined as any injury that resulted from AF ablation, including esophageal injury or periesophageal nerve injury (peri-ENI). Results The incidence of esophageal injury was significantly lower in patients whose AF ablation included ETM compared with patients without ETM (0 [0%] vs. 6 [7.5%], p=0.028), but not the incidence of peri-ENI (2 [2.5%] vs. 3 [3.8%], p=1.0). AF recurrence 12 months after the procedure was similar between the groups (20 [25%] in the ETM group vs. 19 [24%] in the non-ETM group, p=1.00). Conclusions Catheter ablation using ETM may reduce the incidence of esophageal injury without increasing the incidence of AF recurrence but not the incidence of peri-ENI. PMID:26949429
Lawrance, Christopher P; Henn, Matthew C; Damiano, Ralph J
Atrial fibrillation is the most common cardiac arrhythmia, and its treatment options include drug therapy or catheter-based or surgical interventions. The surgical treatment of atrial fibrillation has undergone multiple evolutions over the last several decades. The Cox-Maze procedure went on to become the gold standard for the surgical treatment of atrial fibrillation and is currently in its fourth iteration (Cox-Maze IV). This article reviews the indications and preoperative planning for performing a Cox-Maze IV procedure. This article also reviews the literature describing the surgical results for both approaches including comparisons of the Cox-Maze IV to the previous cut-and-sew method.
Lawrance, Christopher P; Henn, Matthew C; Damiano, Ralph J
Atrial fibrillation is the most common cardiac arrhythmia, and its treatment options include drug therapy or catheter-based or surgical interventions. The surgical treatment of atrial fibrillation has undergone multiple evolutions over the last several decades. The Cox-Maze procedure went on to become the gold standard for the surgical treatment of atrial fibrillation and is currently in its fourth iteration (Cox-Maze IV). This article reviews the indications and preoperative planning for performing a Cox-Maze IV procedure. This article also reviews the literature describing the surgical results for both approaches including comparisons of the Cox-Maze IV to the previous cut-and-sew method.
... attribute childhood AF to congenital heart abnormalities or post-surgical complications. Learn more about children and arrhythmia. This content was last reviewed July 2016. Atrial Fibrillation • Introduction • What is ...
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Introduction Acute atrial fibrillation is rapid, irregular, and chaotic atrial activity of recent onset. Various definitions of acute atrial fibrillation have been used in the literature, but for the purposes of this review we have included studies where atrial fibrillation may have occurred up to 7 days previously. Risk factors for acute atrial fibrillation include increasing age, cardiovascular disease, alcohol, diabetes, and lung disease. Acute atrial fibrillation increases the risk of stroke and heart failure. The condition resolves spontaneously within 24 to 48 hours in more than 50% of people; however, many people will require interventions to control heart rate or restore sinus rhythm. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of interventions to prevent embolism, for conversion to sinus rhythm, and to control heart rate in people with recent-onset atrial fibrillation (within 7 days) who are haemodynamically stable? We searched: Medline, Embase, The Cochrane Library, and other important databases up to April 2014 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 26 studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review, we present information relating to the effectiveness and safety of the following interventions: amiodarone, antithrombotic treatment before cardioversion, atenolol, bisoprolol, carvedilol, digoxin, diltiazem, direct current cardioversion, flecainide, metoprolol, nebivolol, propafenone, sotalol, timolol, and verapamil. PMID:25430048
Giorgi, Mariano A; Miguel, Lucas San
Warfarin is the traditional therapeutic option available to manage thromboembolic risk in atrial fibrillation. The hemorrhagic risk with warfarin depends mainly on the international normalized ratio (INR). Data from randomized controlled trials show that patients have a therapeutic INR (2.00–3.00) only 61%–68% of the time while taking warfarin, and this target is sometimes hard to establish. Many compounds have been developed in order to optimize the profile of oral anticoagulants. We focus on one of them, rivaroxaban, comparing it with novel alternatives, ie, dabigatran and apixaban. The indication for rivaroxaban in nonvalvular atrial fibrillation was evaluated 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). In this trial, rivaroxaban was associated with a 12% reduction in the incidence of the primary endpoint compared with warfarin (hazard ratio 0.88; 95% confidence interval [CI] 0.74–1.03; P < 0.001 for noninferiority and P = 0.12 for superiority). However, patients remained in the therapeutic range for INR only 55% of the time, which is less than that in RE-LY (the Randomized Evaluation of Long-Term Anticoagulation Therapy, 64%) and in the ARISTOTLE trial (Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation, 66%). This shorter time spent in the therapeutic range has been one of the main criticisms of the ROCKET-AF trial, but could actually reflect what happens in real life. In addition, rivaroxaban exhibits good pharmacokinetic and pharmacoeconomic properties. Novel anticoagulants are a viable and commercially available alternative to vitamin K antagonists nowadays for the prevention of thromboembolic complications in atrial fibrillation. Rivaroxaban is an attractive alternative, but the true picture of this novel compound in atrial fibrillation will only become available with more widespread
Lawrance, Christopher P.; Henn, Matthew C.; Damiano, Ralph J.
Synopsis Atrial fibrillation is the most common cardiac arrhythmia and its treatment options include drug therapy or, catheter-based or surgical interventions. The surgical treatment of atrial fibrillation has undergone multiple evolutions over the last several decades. The Cox-Maze procedure which was developed by James Cox in 1987 is a procedure where multiple surgical incisions are created along the atria to interrupt the electrical pathways thought to allow atrial fibrillation to persist. This procedure went on to become the gold standard for the surgical treatment of atrial fibrillation and is currently in its 4th iteration called the Cox-Maze IV. The Cox-Maze IV replaced the previous “cut-and-sew” method with a combination of cryoablation and bipolar RF ablation. The adaption of ablation technologies allowed the Cox-Maze IV procedure to be performed through a less invasive right minithoracotomy instead of a traditional sternotomy approach. The aim of this article is to review the indications and preoperative planning for performing a Cox-Maze IV procedure. A description of the operative techniques for both a sternotomy and right mini-thoracotomy approach will be discussed in addition to specific postoperative considerations. Finally, this article will review the literature describing the surgical results for both approaches including comparisons of the Cox-Maze IV to the previous “cut-and-sew” method. PMID:25443237
Chang, Kay-Won; Hsu, Jonathan C; Toomu, Avinash; Fox, Sutton; Maisel, Alan S
While biomarkers have greatly impacted the diagnosis and management of myocardial infarction and heart failure, the use of biomarkers has been slow to permeate management of atrial fibrillation. Guideline recommendations on the use of biomarkers in atrial fibrillation were virtually non-existent until the 2016 European Society of Cardiology guidelines on atrial fibrillation offered a class IIb recommendation to consider using biomarkers such as high sensitivity troponin and natriuretic peptide to further refine stroke and bleeding risk in atrial fibrillation patients. Biomarker levels have been associated with incident atrial fibrillation, post-operative atrial fibrillation, acute atrial fibrillation, diagnosis of myocardial infarction and heart failure in atrial fibrillation, and prognosis in atrial fibrillation. This review will offer an in-depth survey of current evidence on the use of biomarkers in atrial fibrillation and propose clinical algorithms to aid the internist in using biomarkers in atrial fibrillation management. Copyright © 2017. Published by Elsevier Inc.
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
Franken, Roberto A.; Rosa, Ronaldo F.; Santos, Silvio CM
This review discusses atrial fibrillation according to the guidelines of Brazilian Society of Cardiac Arrhythmias and the Brazilian Cardiogeriatrics Guidelines. We stress the thromboembolic burden of atrial fibrillation and discuss how to prevent it as well as the best way to conduct cases of atrial fibrillatios in the elderly, reverting the arrhythmia to sinus rhythm, or the option of heart rate control. The new methods to treat atrial fibrillation, such as radiofrequency ablation, new oral direct thrombin inhibitors and Xa factor inhibitors, as well as new antiarrhythmic drugs, are depicted. PMID:22916053
Atienza, Felipe; Jalife, José
The mechanisms of human atrial fibrillation (AF) are poorly understood. Experimental studies have demonstrated that cholinergic AF in the sheep heart is maintained by high-frequency reentrant sources (drivers) that result in a consistent left-to-right frequency gradient. More recently, clinical studies have confirmed the existence of a hierarchical organization in the rate of activation of different regions in the atria of patients with paroxysmal and chronic AF. Although maximal dominant-frequency sites were found to play a crucial role in the maintenance of AF in some patients, whether AF drivers in humans are focal or reentrant and whether changes in driver activity alter spatial frequency gradients are unclear. To test the hypothesis that localized functional reentry maintains AF in humans, we determined the effects of adenosine infusion on local dominant frequency at different sites of both atria. In patients with paroxysmal AF, adenosine infusion increases local dominant frequencies, particularly at the pulmonary vein-left atrial junction region, amplifying a left-to-right frequency gradient. In patients with chronic AF, dominant frequency is significantly higher than in patients with paroxysmal AF in all atrial regions surveyed, with the highest adenosine increase of frequencies outside the pulmonary vein region. Adenosine-induced driver acceleration is strongly suggestive of a reentrant mechanism in both groups of AF patients.
Gladstone, David J; Spring, Melanie; Dorian, Paul; Panzov, Val; Thorpe, Kevin E; Hall, Judith; Vaid, Haris; O'Donnell, Martin; Laupacis, Andreas; Côté, Robert; Sharma, Mukul; Blakely, John A; Shuaib, Ashfaq; Hachinski, Vladimir; Coutts, Shelagh B; Sahlas, Demetrios J; Teal, Phil; Yip, Samuel; Spence, J David; Buck, Brian; Verreault, Steve; Casaubon, Leanne K; Penn, Andrew; Selchen, Daniel; Jin, Albert; Howse, David; Mehdiratta, Manu; Boyle, Karl; Aviv, Richard; Kapral, Moira K; Mamdani, Muhammad
Atrial fibrillation is a leading preventable cause of recurrent stroke for which early detection and treatment are critical. However, paroxysmal atrial fibrillation is often asymptomatic and likely to go undetected and untreated in the routine care of patients with ischemic stroke or transient ischemic attack (TIA). We randomly assigned 572 patients 55 years of age or older, without known atrial fibrillation, who had had a cryptogenic ischemic stroke or TIA within the previous 6 months (cause undetermined after standard tests, including 24-hour electrocardiography [ECG]), to undergo additional noninvasive ambulatory ECG monitoring with either a 30-day event-triggered recorder (intervention group) or a conventional 24-hour monitor (control group). The primary outcome was newly detected atrial fibrillation lasting 30 seconds or longer within 90 days after randomization. Secondary outcomes included episodes of atrial fibrillation lasting 2.5 minutes or longer and anticoagulation status at 90 days. Atrial fibrillation lasting 30 seconds or longer was detected in 45 of 280 patients (16.1%) in the intervention group, as compared with 9 of 277 (3.2%) in the control group (absolute difference, 12.9 percentage points; 95% confidence interval [CI], 8.0 to 17.6; P<0.001; number needed to screen, 8). Atrial fibrillation lasting 2.5 minutes or longer was present in 28 of 284 patients (9.9%) in the intervention group, as compared with 7 of 277 (2.5%) in the control group (absolute difference, 7.4 percentage points; 95% CI, 3.4 to 11.3; P<0.001). By 90 days, oral anticoagulant therapy had been prescribed for more patients in the intervention group than in the control group (52 of 280 patients [18.6%] vs. 31 of 279 [11.1%]; absolute difference, 7.5 percentage points; 95% CI, 1.6 to 13.3; P=0.01). Among patients with a recent cryptogenic stroke or TIA who were 55 years of age or older, paroxysmal atrial fibrillation was common. Noninvasive ambulatory ECG monitoring for a target of
Arguis, M J; Navarro, R; Regueiro, A; Arbelo, E; Sierra, P; Sabaté, S; Galán, J; Ruiz, A; Matute, P; Roux, C; Gomar, C; Rovira, I; Mont, L; Fita, G
Atrial fibrillation is a frequent complication in the perioperative period. When it appears there is an increased risk of perioperative morbidity due to stroke, thromboembolism, cardiac arrest, myocardial infarction, anticoagulation haemorrhage, and hospital readmissions. The current article focuses on the recommendations for the management of perioperative atrial fibrillation based on the latest Clinical Practice Guidelines on atrial fibrillation by the European Society of Cardiology and the Spanish Society of Cardiology. This article pays special attention to the preoperative management, as well as to the acute perioperative episode. For this reason, the latest recommendations for the control of cardiac frequency, antiarrhythmic treatment and anticoagulation are included.
Jadidi, Amir S; Sunthorn, Henri; Burri, Haran; Gentil-Baron, Pascale; Shah, Dipen
A 19-year-old girl was referred to our cardiology department for catheter ablation (isolation of the pulmonary veins) of paroxysmal atrial fibrillation (AF). The diagnosis was made upon a 12-lead ECG of the arrhythmia documented in the emergency room. The ECG showed an irregular tachycardia without wide QRS complexes. Careful assessment revealed the irregularity of the rhythm was a sweep artifact due to a mechanic failure of the ECG-machine to advance the article smoothly. During EP study a concealed anteroseptal accessory pathway causing an orthodromic AV reentrant tachycardia was eliminated by radio-frequency ablation. This example emphasizes the need for careful assessment of an ECG tracing, including printed legends and technical data.
Sullivan, M L; Martinez, C M; Gallagher, E J
A young male bodybuilder, consuming large doses of anabolic steroids (AS), presented to the Emergency Department (ED) with symptomatic rapid atrial fibrillation (AF). Echocardiogram revealed significant septal hypokinesis, and posterior and septal wall thickness at the upper limit of normal for highly trained athletes. The atrial fibrillation had not recurred at 10 weeks after discontinuation of AS use. Consumption of these agents in athletes has been associated with hypertension, ischemic heart disease, hypertrophic cardiomyopathy, and sudden death.
Piccini, Jonathan P; Fauchier, Laurent
Many patients with atrial fibrillation have substantial symptoms despite ventricular rate control and require restoration of sinus rhythm to improve their quality of life. Acute restoration (ie, cardioversion) and maintenance of sinus rhythm in patients with atrial fibrillation are referred to as rhythm control. The decision to pursue rhythm control is based on symptoms, the type of atrial fibrillation (paroxysmal, persistent, or long-standing persistent), patient comorbidities, general health status, and anticoagulation status. Many patients have recurrent atrial fibrillation and require further intervention to maintain long term sinus rhythm. Antiarrhythmic drug therapy is generally recommended as a first-line therapy and drug selection is on the basis of the presence or absence of structural heart disease or heart failure, electrocardiographical variables, renal function, and other comorbidities. In patients who continue to have recurrent atrial fibrillation despite medical therapy, catheter ablation has been shown to substantially reduce recurrent atrial fibrillation, decrease symptoms, and improve quality of life, although recurrence is common despite continued advancement in ablation techniques.
Atrial fibrillation in heart failure often occur together. The relationship between atrial fibrillation and heart failure has remained a subject of research. The main manifestation of the violation of hydrodynamics in heart failure is the increased end-diastolic pressure, which is transmitted through the intercommunicated system (left ventricle-left atrium-pulmonary veins-alveolar capillaries) causing increased pulmonary wedge pressure with the danger for pulmonary edema. End-diastolic pressure is the sum of left ventricle diastolic pressure and left atrial systolic pressure. Stopping the mechanical systole of the left atrium can reduce the pressure in the system in heart failure. Atrial fibrillation stops the mechanical systole of the left atrium and decreases the intercommunicating pressure and pulmonary wedge pressure. It is possible that atrial fibrillation is a mechanism for protection from increasing end-diastolic pressure and pulmonary wedge pressure, and prevents the danger of pulmonary edema. This hypothesis may explain the relationship between heart failure and atrial fibrillation and their frequent association. Copyright © 2014 Elsevier Ltd. All rights reserved.
Kanjwal, Yousuf; Imran, Naser; Grubb, Blair
Deglutition induced supraventricular tachycardia is an uncommon condition postulated to be a vagally mediated phenomenon due to mechanical stimulation. Patients usually present with mild symptoms or may have severe debilitating symptoms. Treatment with Class I agents, beta blockers, calcium channel blockers, amiodarone and radiofrquency catheter ablation has shown to be successful in the majority of reported cases. We report the case of a 46-year-old healthy woman presenting with palpitations on swallowing that was documented to be transient atrial tachycardia with aberrant ventricular conduction as well as transient atrial fibrillation. She was successfully treated with propafenone with no induction of swallowing-induced tachycardia after treatment. This is also the first case to show swallowing-induced atrial tachycardia and atrial fibrillation in the same patient.
Castrejón-Castrejón, Sergio; Ortega, Marta; Pérez-Silva, Armando; Doiny, David; Estrada, Alejandro; Filgueiras, David; López-Sendón, José L.; Merino, José L.
The efficacy of catheter-based ablation techniques to treat atrial fibrillation is limited not only by recurrences of this arrhythmia but also, and not less importantly, by new-onset organized atrial tachycardias. The incidence of such tachycardias depends on the type and duration of the baseline atrial fibrillation and specially on the ablation technique which was used during the index procedure. It has been repeatedly reported that the more extensive the left atrial surface ablated, the higher the incidence of organized atrial tachycardias. The exact origin of the pathologic substrate of these trachycardias is not fully understood and may result from the interaction between preexistent regions with abnormal electrical properties and the new ones resultant from radiofrequency delivery. From a clinical point of view these atrial tachycardias tend to remit after a variable time but in some cases are responsible for significant symptoms. A precise knowledge of the most frequent types of these arrhythmias, of their mechanisms and components is necessary for a thorough electrophysiologic characterization if a new ablation procedure is required. PMID:21941669
Lanters, Eva A H; Allessie, Maurits A; DE Groot, Natasja M S
The incidence and appearance of focal fibrillation waves on the right and left atrial epicardial surface were visualized during 10 seconds of persistent atrial fibrillation in a 71-year-old woman with valvular heart disease. The frequent, nonrepetitive, widespread, and capricious distribution of focal waves suggests that transmural conduction of fibrillation waves is most likely the mechanism underlying focal fibrillation waves.
Heart is easy to be affected by the abnormal thyroid function because cardiac muscle cells have many thyroid hormone receptors. In addition, thyroid hormone goes higher sensitivity to sympathetic nerve as it increases the number of myocardial beta receptor. Therefore, when the thyroid hormone is excessive value, tachycardia and atrial fibrillation may occur regardless of the cause. The atrial fibrillation in Graves' disease can expect spontaneous reversion to sinus rhythm when the hyperthyroidism is controlled. However, cardioversion is indicated for patients who have not returned to sinus rhythm for at least 3 months after the hyperthyroidism is controlled. In this paper, we report the relationship between hyperthyroidism and heart, and the treatment of atrial fibrillation in Graves' disease.
Olazabal Eizaguirre, N; Chavez, R; González-Torres, M A; Gaviria, M
This paper studies the relationship between atrial fibrillation and panic disorder. There are often doubts on the differential diagnosis in emergency services and general medical settings. Panic disorder prevalence rates have been found to be high in patients suffering from atrial fibrillation. Various studies have observed that patients diagnosed with anxiety disorders frequently have higher cardiovascular disease rates compared to the general population. Usually, patients suffering from panic disorder exhibit somatic complaints suggesting coronary disease, such as chest pain or palpitations. The aim is to make the correct diagnosis and treatment for these different illnesses, and to decrease the costs due to misdiagnosis.
Atrial fibrillation is the most frequent arrhythmia. Its "lone" form (when underlying pathology is not discovered) can be detected in a small percentage of endurance sports participants, and in growing numbers among veterans, probably as a result of some cardiac or other irregularities. Enhanced vagal tone and sudden sympathetic impulse, repetitive oxidative stress, inflammatory processes, enlarged atria, electric instabilization can explain the higher occurrence. Treatment of atrial fibrillation enables the affected persons to participate in regular medium-intensity exercise, 3-5 hours a week, which offers a protective role against cardiovascular, metabolic and mental illnesses.
Syed, Faisal F.; DeSimone, Christopher V.; Friedman, Paul A.; Asirvatham, Samuel J.
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
Ramlawi, Basel; Abu Saleh, Walid K
The Cox-maze procedure for the restoration of normal sinus rhythm, initially developed by Dr. James Cox, underwent several iterations over the years. The main concept consists of creating a series of transmural lesions in the right and left atria that disrupt re-entrant circuits responsible for propagating the abnormal atrial fibrillation rhythm. The left atrial appendage is excluded as a component of the Maze procedure. For the first three iterations of the Cox- maze procedure, these lesions were performed using a surgical cut-and-sew approach that ensured transmurality. The Cox-Maze IV is the most currently accepted iteration. It achieves the same lesion set of the Cox- maze III but uses alternative energy sources to create the transmural lesions, potentially in a minimally invasive approach on the beating heart. High-frequency ultrasound, microwave, and laser energy have all been used with varying success in the past. Today, bipolar radiofrequency heat or cryotherapy cooling are the most accepted sources for creating linear lesions with consistent safety and transmurality. The robust and reliable nature of these energy delivery methods has yielded a success rate reaching 90% freedom from atrial fibrillation at 12 months. Such approaches offer a significant long-term advantage over catheter-based ablation, especially in patients having longstanding, persistent atrial fibrillation with characteristics such as dilated left atrial dimensions, poor ejection fraction, and failed catheter ablation. Based on these improved results, there currently is significant interest in developing a hybrid ablation strategy that incorporates the superior transmural robust lesions of surgical ablation, the reliable stroke prevention potential of epicardial left atrial appendage exclusion, and sophisticated mapping and confirmatory catheter-based ablation technology. Such a minimally invasive hybrid strategy for ablation may lead to the development of multidisciplinary "Afib teams" to
Sághy, László; Tutuianu, Cristina; Szilágyi, Judith
One of the most important proarrhythmic complications after left atrial (LA) ablation is regular atrial tachycardia (AT) or flutter. Those tachycardias that occur after atrial fibrillation (AF) ablation can cause even more severe symptoms than those from the original arrhythmia prior to the index ablation procedure since they are often incessant and associated with rapid ventricular response. Depending on the method and extent of LA ablation and on the electrophysiological properties of underlying LA substrate, the reported incidence of late ATs is variable. To establish the exact mechanism of these tachycardias can be difficult and controversial but correlates with the ablation technique and in the vast majority of cases the mechanism is reentry related to gaps in prior ablation lines. When tachycardias occur, conservative therapy usually is not effective, radiofrequency ablation procedure is mostly successful, but can be challenging, and requires a complex approach. PMID:25308808
Malik, Amyn; Ali, Syed Sohail; Rahmatullah, Amin
We present the case of 38-year-old woman who experienced palpitations on swallowing, which were later found to be atrial fibrillation. Her symptoms improved on treatment with disopyramide and verapamil. Within 9 months, she was weaned from both medications without recurrence of symptoms. PMID:16429915
Duron, Emmanuelle; Hanon, Olivier
Atrial fibrillation (AF), which prevalence increases with age, is a growing public health problem and a well known risk factor for stroke. On the other hand, dementia is one of the most important neurological disorders in the elderly, and with aging of the population in developed countries, the number of demented patients will increase in absence of prevention. In the past decade, several vascular risk factors (hypertension, obesity and metabolic syndrome, hypercholesterolemia) have been found, with various degree of evidence, to be associated with vascular dementia but also, surprisingly, with Alzheimer's disease. This review is devoted to the links between atrial fibrillation, cognitive decline and dementia. Globally, transversal studies showed a significant association between atrial fibrillation, cognitive decline and dementia. However, these studies are particularly sensitive to various biases. In this context, recent longitudinal studies of higher level of evidence have been conducted to assess the link between AF and dementia. One study disclosed a high incidence of dementia among patients suffering from atrial fibrillation during a 4.6 years follow-up. Similarly another study showed that atrial fibrillation was significantly associated with conversion from mild cognitive impairment to dementia during a 3 years follow-up. Nevertheless two other longitudinal studies did not find any significant association between AF and dementia, but this discrepancy should be interpreted taking into account that the comparability of all these studies is moderate because they were using different methodologies (population, cognitive testing, and mean follow-up). Possible explanatory mechanisms for the association between AF and the risk of dementia are proposed, such as thrombo-embolic ischemic damage and cerebral hypo perfusion due to fluctuations in the cardiac output. Thus, there is some evidence that FA could be associated with cognitive decline and dementia but this
Sternik, Leonid; Schaff, Hartzel V.; Luria, David; Glikson, Michael; Kogan, Alexander; Malachy, Ateret; First, Maya; Raanani, Ehud
The maze procedure is the gold standard for the ablation of atrial fibrillation, and the “box lesion” around the pulmonary veins is the most important part of this procedure. We have created this lesion with a bipolar radiofrequency ablator, abandoning the usual use of this device (to achieve bilateral epicardial isolation of the pulmonary veins). From March 2004 through the end of May 2010, we performed surgical ablation of atrial fibrillation in 240 patients. Of this number, 205 underwent operation by a hybrid maze technique and the remaining 35 (our study cohort) underwent the creation of a box lesion around the pulmonary veins by means of a bipolar radiofrequency device. Ablation lines were created by connecting the left atriotomy to the amputated left atrial appendage, with 2 ablation lines made with a bipolar radiofrequency device above and below the pulmonary veins. Lesions were made along the transverse and oblique sinuses by epicardial and endocardial application of a bipolar device. The left atrial isthmus was ablated by bipolar radiofrequency and cryoprobe. No complications were associated with the box lesion: 90% and 89% of patients were in sinus rhythm at 3 and 6 months of follow-up, respectively. By creating a box lesion around the pulmonary veins, we expect to improve transmurality by means of epicardial and endocardial ablation of 1 rather than 2 layers of atrial wall, as in epicardial pulmonary vein isolation. Isolation of the entire posterior wall of the left atrium is better electrophysiologically and renders dissection around the pulmonary veins unnecessary. PMID:21494518
In selected patients with atrial fibrillation and severe symptoms, non-pharmacological treatment may be an alternative or supplement to drug therapy. Atrioventricular nodal radiofrequency ablation (requires pacemaker implantation), or atrial pacing for sick sinus syndrome, are established treatment modalities. All other non-pharmacological therapies for atrial fibrillation are still experimental. After the Maze operation, atrial depolarization has to follow one specific path determined by surgical scars in the myocardium. This prevents new episodes of atrial fibrillation, but at a cost of perioperative morbidity and mortality. Catheter-based "Maze-like" radiofrequency ablation is technically difficult, and thrombo-embolic complications may occur. Paroxysmal atrial fibrillation sometimes is initiated by spontaneous depolarizations in a pulmonary vein inlet. Radio frequency ablation against such focal activity has been reported with high therapeutic success, but the results await confirmation from several centres. For ventricular rate control, most electrophysiologists presently prefer ablation to induce a complete atrioventricular conduction block (with pacemaker) rather than trying to modify conduction by incomplete block. Atrial or dual chamber pacing may prevent atrial fibrillation induced by bradycardia. It remains to confirm that biatrial or multisite right atrial pacing prevents atrial fibrillation more efficiently than ordinary right atrial pacing. An atrial defibrillator is able to diagnose and convert atrial fibrillation. The equipment is expensive, and therapy without sedation may be unpleasant beyond tolerability.
Bauer, Peter A.; Polk, J. D.
This presentation will explore the clinical and administrative conundrums faced by the flight surgeon upon discovering asymptomatic paroxysmal atrial fibrillation seven months prior to scheduled long duration spaceflight. The presenter will discuss the decision-making process as well as the clinical and operational outcomes.
Dang, David; Arimie, Raluca; Haywood, L. Julian
Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and accounts for more physician visits and hospital days than any other cardiac rhythm disturbance. Atrial filbrillation is incresing in frequency as the population ages, and therefore, a knowledge of the clinical spectrum and available treatment regimen is essential. Here, we review the pathophysiology, clinical presentation, and current status of management. Experience is being rapidly accumulated in all of the areas discussed in the management of this important clinical entity. Images Figure 1 Figure 2 PMID:12510703
... What Are the Signs and Symptoms of Atrial Fibrillation? Atrial fibrillation (AF) usually causes the heart's lower ... pain Dizziness or fainting Fatigue (tiredness) Confusion Atrial Fibrillation Complications AF has two major complications— stroke and ...
Lairikyengbam, S; Anderson, M; Davies, A
Atrial fibrillation is the commonest sustained cardiac arrhythmia. It accounts for >35% of all hospital admissions for cardiac arrhythmias in the United States. The presence of atrial fibrillation increases the mortality of a population by up to twofold. The risk of stroke increases from 1.5% in patients with atrial fibrillation from 50–59 years of age to up to 23.5% for such patients aged 80–89 years. Although the diagnosis of atrial fibrillation is usually straightforward, effective treatment is not. This article will discuss how rhythm control of atrial fibrillation can best be achieved, the controversy over the rhythm versus rate control, the maintenance of sinus rhythm with antiarrhythmic drugs after cardioversion, and prevention of thromboembolism. Finally, the recent advances in various non-pharmacological approaches for the treatment of atrial fibrillation will be highlighted. PMID:12612318
Jawad-Ul-Qamar, Muhammad; Kirchhof, Paulus
Atrial fibrillation continues to attract interest in the cardiovascular community and in Heart. Over 60 original research and review papers published in Heart in 2014–2015 cover various aspects of atrial fibrillation, from associated conditions and precipitating factors to new approaches to management. Here, we provide an overview of articles on atrial fibrillation published in Heart in 2014–2015, highlighting new developments, emerging concepts and novel approaches to treatment. PMID:26791994
Park, Young-Ah; Seo, Jiwon
When there is no pulmonary vein reconnection after catheter ablation for atrial fibrillation, patients can experience recurrence of atrial fibrillation without clear evidence of non-pulmonary vein foci. We describe a patient with significant pulmonary vein stenosis and recurrent atrial fibrillation after four ablation procedures. After successful pulmonary vein stenting, the symptoms were resolved, and sinus rhythm was maintained for 2 years without treatment with antiarrhythmic medication. We believe pulmonary vein stenting potentially controlled atrial fibrillation by providing pulmonary vein pressure relief or by compressing the epicardial triggers occurring at the pulmonary vein ostium. PMID:28765746
There is a growing population of veteran endurance athletes, regularly participating in training and competition. Although the graded benefit of exercise on cardiovascular health and mortality is well established, recent studies have raised concern that prolonged and strenuous endurance exercise may predispose to atrial and ventricular arrhythmias. Atrial fibrillation (AF) and atrial flutter are facilitated by atrial remodelling, atrial ectopy, and an imbalance of the autonomic nervous system. Endurance sports practice has an impact on all of these factors and may therefore act as a promoter of these arrhythmias. In an animal model, long-term intensive exercise training induced fibrosis in both atria and increased susceptibility to AF. While the prevalence of AF is low in young competitive athletes, it increases substantially in the aging athlete, which is possibly associated with an accumulation of lifetime training hours and participation in competitions. A recent meta-analysis revealed a 5-fold increased risk of AF in middle-aged endurance athletes with a striking male predominance. Beside physical activity, height and absolute left atrial size are independent risk factors for lone AF and the stature of men per se may explain part of their higher risk of AF. Furthermore, for a comparable amount of training volume and performance, male non-elite athletes exhibit a higher blood pressure at rest and peak exercise, a more concentric type of left ventricular remodelling, and an altered diastolic function, possibly contributing to a more pronounced atrial remodelling. The sports cardiologist should be aware of the distinctive features of AF in athletes. Therapeutic recommendations should be given in close cooperation with an electrophysiologist. Reduction of training volume is often not desired and drug therapy not well tolerated. An early ablation strategy may be appropriate for some athletes with an impaired physical performance, especially when continuation of
Sherman, David G
Atrial fibrillation is a common arrhythmia associated with increased risk for embolic stroke. Restoration of sinus rhythm in patients with atrial fibrillation is a logical strategy to prevent the cardiovascular and thromboembolic complications of this dysrhythmia. The most common strategy for restoration of sinus rhythm is pharmacological antiarrhythmic therapy with or without electrical cardioversion. Five randomized clinical trials compared rhythm to rate-control strategies in patients with atrial fibrillation. These trials examined mortality, thromboembolic complications, exercise tolerance, quality of life, hospital admissions and drug-related adverse reactions. Mortality ranged from 2.9% to 23.8% among the trial subjects randomized to rhythm control versus 1.0% to 21.3% in the rate control subjects. The risk of thromboemboli was greater: 2.9% to 7.9% in the rhythm-control subjects compared with 0% to 5.5% in the rate control subjects. Hospital admissions and drug-related adverse events were increased in the rhythm-control subjects. Stroke and systemic emboli occurred more often in the rhythm-control subjects many of whom had been withdrawn from anticoagulation. Rhythm-control offered no advantage compared with rate control for patients with atrial fibrillation at increased risk for stroke. One explanation for this finding is that those patients thought to have been successfully converted to sinus rhythm in fact had asymptomatic paroxysmal episodes of atrial fibrillation increasing their risk of stroke because they were unprotected by anticoagulation. Pharmacological attempts to restore atrial fibrillation to sinus rhythm do not improve mortality or reduce thromboembolic events. All patients with atrial fibrillation at increased risk for stroke should be continued on long-term anticoagulation even if they appear to have been successfully restored to sinus rhythm.
Dilber, Dario; Čerkez-Habek, Jasna; Barić, Hrvoje; Gradišer, Marina
Atrial fibrillation (AF) is the most common arrhythmia and it is an independent risk for serious events. Acupuncture has been growing in popularity in the West, and there are reports of its benefits in treating AF. We report a 57-year-old man who was admitted after having an allergic reaction to amiodarone administered to treat paroxysmal AF with fast ventricular response. Cardioversion with intravenous propafenone was uneventful. Before an attempt of electric cardioversion, he was treated with acupuncture as additional therapy to peroral propafenone. After acupuncture treatment consisting of 10 treatments during 30 days period, both immediate cardioversion to sinus rhythm and no paroxysmal AF during 30 days period were recorded.
Nakamura, Yoshitsugu; Kiaii, Bob; Chu, Michael W. A.
Atrial fibrillation is the most common sustained arrhythmia and is associated with significant risks of thromboembolism, stroke, congestive heart failure, and death. There have been major advances in the management of atrial fibrillation including pharmacologic therapies, antithrombotic therapies, and ablation techniques. Surgery for atrial fibrillation, including both concomitant and stand-alone interventions, is an effective therapy to restore sinus rhythm. Minimally invasive surgical ablation is an emerging field that aims for the superior results of the traditional Cox-Maze procedure through a less invasive operation with lower morbidity, quicker recovery, and improved patient satisfaction. These novel techniques utilize endoscopic or minithoracotomy approaches with various energy sources to achieve electrical isolation of the pulmonary veins in addition to other ablation lines. We review advancements in minimally invasive techniques for atrial fibrillation surgery, including management of the left atrial appendage. PMID:22666609
Marcus, Gregory M.; Olgin, Jeffrey E.; Whooley, Mary; Vittinghoff, Eric; Stone, Katie L.; Mehra, Reena; Hulley, Stephen B.; Schiller, Nelson B.
BACKGROUND Previous studies relying on clinical care data have suggested that atrial fibrillation is less common in African Americans than Caucasians, but the mechanism remains unknown. Clinical care may itself vary by race, potentially affecting the accuracy of atrial fibrillation ascertainment in studies relying on clinical data. We sought to examine racial differences in atrial fibrillation prevalence determined by protocol-driven electrocardiograms (ECGs) obtained in prospective cohort studies and to study racial differences in echocardiographic characteristics. METHODS We pooled primary data from 3 cohort studies with atrial fibrillation adjudicated from study protocol ECGs and documentation of potentially important confounders: the Heart and Soul Study (n = 1014), the Heart and Estrogen-Progestin Replacement Study (n = 2673), and The Osteoporotic Fractures in Men Sleep Study (n = 2911). Left atrial anatomic dimensions were compared among races from sinus rhythm echocardiograms in the Heart and Soul Study. RESULTS Of the 6611 participants, 268 (4%) had atrial fibrillation: Caucasians had the highest prevalence (5%), and African Americans had the lowest (1%; P <.001 for each compared with all other races). After adjustment for potential confounders, Caucasians had a 3.8-fold greater odds of having atrial fibrillation than African Americans (95% confidence interval, 1.6–8.8, P = .002). Although ventricular and atrial volumes and function were similar in Caucasians and African Americans, Caucasians had a 2 mm larger anterior-posterior left atrial diameter after adjusting for potential confounders (95% confidence interval, 1–3 mm, P <.001). CONCLUSION ECG confirmed atrial fibrillation is more common in Caucasians than in African Americans, which might be related to the larger left atrial diameter observed in Caucasians. PMID:20227049
Carasso, Shemy; Kuperstein, Rafael; Konen, Eli; Glikson, Michael; Feinberg, Micha S
We present two patients with a large left atrial (LA) thrombus following invasive treatment for atrial fibrillation and inadequate anticoagulation. Case 1: A 30-year-old woman, with a one-year history of symptomatic paroxysmal atrial fibrillation resistant to medical therapy, underwent catheter ablation for atrial fibrillation. Three days after the procedure the patient presented with dizziness, fatigue, rapid atrial fibrillation with a sub-therapeutic INR. Transesophageal echocardiography (TEE) revealed a large LA thrombus. Case 2: A 59-year-old male, with severe mitral regurgitation and chronic atrial fibrillation, underwent mitral valve repair and Cox-Maze procedure. Three months later, while asymptomatic, a follow-up transthoracic echocardiography a large posterior LA thrombus was imaged. His INR was also sub-therapeutic. Both patients were treated by enhancing anticoagulation and close echocardiographic follow-up. So far both patients have remained asymptomatic two months following discharge. Large LA thrombi detected by transthoracic echocardiography are a rare complication of the Cox-Maze procedure and radio-frequency ablation for atrial fibrillation, which may occur even in patients with restored normal sinus rhythm receiving inadequate anticoagulation therapy.
Ko, Darae; Rahman, Faisal; Martins, Maria A. P.; Hylek, Elaine M.; Ellinor, Patrick T.; Schnabel, Renate B.; Benjamin, Emelia J.; Christophersen, Ingrid E.
Sex-specific differences in the epidemiology, pathophysiology, presentation, prognosis, and treatment of atrial fibrillation (AF) are increasingly recognized. Women with AF generally experience worse symptoms, poorer quality of life, and have higher risk of stroke and death than men with AF. Effective treatment of the arrhythmia in women is critical to reduce the rate of adverse events. We review the current evidence on sex-specific differences in the utilization and outcomes of treatments for AF, including rate-control and rhythm-control strategies, and stroke-prevention therapy. In addition, we provide a critical evaluation of potential disparities and biases in health-care use that may be associated with differences in the outcomes between women and men.We underscore current knowledge gaps that need to be addressed in future studies to improve the management of AF in women. In particular, we suggest several strategies to produce quality evidence from randomized, clinical trials for women with AF. PMID:27786235
Dilber, Dario; Čerkez-Habek, Jasna; Barić, Hrvoje; Gradišer, Marina
Atrial fibrillation (AF) is the most common arrhythmia and it is an independent risk for serious events. Acupuncture has been growing in popularity in the West, and there are reports of its benefits in treating AF. We report a 57-year-old man who was admitted after having an allergic reaction to amiodarone administered to treat paroxysmal AF with fast ventricular response. Cardioversion with intravenous propafenone was uneventful. Before an attempt of electric cardioversion, he was treated with acupuncture as additional therapy to peroral propafenone. After acupuncture treatment consisting of 10 treatments during 30 days period, both immediate cardioversion to sinus rhythm and no paroxysmal AF during 30 days period were recorded. PMID:26593171
... most common complication after heart surgery . View an animation of atrial fibrillation. Usually, the most serious risk ... patterns of the heart’s electrical system. View an animation of a normal heartbeat. The heart’s normal electrical ...
Alexa, Ioana Dana; Bucur, Ionela Mirela; Rusu, R I; Ungureanu, G
Atrial fibrillation (AF), a common and serious cardiac rhythm disturbance, is responsible for substantial morbidity and mortality in the population. Currently about 2.3 million people in the US are diagnosed with AF and, based of the US census, this number is expected to rise to 5.6 million by 2050. It doubles in prevalence with each decade of age, reaching almost 9% at age 80-89 years. It has increased in prevalence over the calendar decades, reaching 'epidemic' proportions. The risk of stroke increases from 1.5% in patients with atrial fibrillation from 50-59 years of age to up to 23.5% for such patients aged 80-89 years. Although the diagnosis of atrial fibrillation is usually straightforward, effective treatment is not. We aimed to discuss how rhythm control of atrial fibrillation can best be achieved in elderly patients, the controversy over the rhythm versus rate control, and prevention of thromboembolism.
Lipsett, Mark; Hamilton, Douglas; Lemery, Jay; Polk, James
This slide presentation reviews a possible scenario of an astronaut having Atrial Fibrillation during a Mars Mission. In the case review the presentation asks several questions about the alternatives for treatment, medications and the ramifications of the decisions.
Máquez, Manlio F; Gómez Flores, Jorge
Radiofrequency catheter ablation has emerged as a curative therapy for paroxysmal atrial fibrillation based on studies demonstrating the role of triggering foci in the pulmonary veins for the initiation of atrial fibrillation. Catheter ablation is performed by a trans-septal approach using radiofrequency energy at the ostium of each pulmonary vein. Mapping is guided by special catheters. Sequential radiofrequency applications eliminates or dissociates pulmonary vein muscle activity. Although complications exists, this procedure can be curative for these patients.
Antz, Matthias; Hullmann, Bettina; Neufert, Christian; Vocke, Wolfgang
The correct anticoagulation regimen for prevention of thromboembolic events is essential in patients with atrial fibrillation. However, only a minority of patients receives anticoagulation according to the guidelines. The current guidelines are intended to make the indication for anticoagulation more simple and are summarized in the present article. This includes recommendations for chronic anticoagulation, prevention of thromboembolic events after cardioversion and in ablation of atrial fibrillation.
Staffurth, J S; Gibberd, M C; Fui, S N
In 262 patients with thyrotoxicosis and atrial fibrillation there were 26 episodes of arterial embolism (17 cerebral and nine elsewhere) in 21 patients. Twelve incidents occurred with active thyrotoxicosis, three on reversion to sinus rhythm, and 11 after the patients were euthyroid. This important complication is more common than is realised, and most patients should be put on prophylactic anticoagulants when first seen with atrial fibrillation. PMID:902055
Le Heuzey, J Y
The incidence and prevalence of atrial fibrillation are quickly increasing, mainly due to the ageing of the population. Atrial fibrillation is, to date, a problem of public health. Atrial fibrillation is associated to a five-fold risk of stroke, which may be identified by score risks, such as CHADS(2) score. The classical antithrombotic treatment of atrial fibrillation is based on vitamin K antagonists. Trials made in the 90's have clearly shown that vitamin K antagonists were able to decrease stroke risk by about 60%. New oral anticoagulants are now available on the market to treat patients with atrial fibrillation. These drugs are dabigatran which has demonstrated an interest in the RE-LY trial. Two doses may be prescribed, 110 mg bid and 150 mg bid. Anti Xa have also demonstrated an interest : rivaroxaban in the ROCKET AF trial and apixaban in the AVERROES (versus aspirin) and ARISTOTLE trials. In the future these drugs will have a major place in the armamentarium used to treat patients with atrial fibrillation. In all these trials a decrease in intra cranial haemorrhages has been demonstrated. In the everyday practice it will be necessary to be very cautious in patients with impaired renal function, as all these drugs are eliminated by kidneys.
Batal, Omar; Schoenhagen, Paul; Shao, Mingyuan; Ayyad, Ala Eddin; Van Wagoner, David R.; Halliburton, Sandra S.; Tchou, Patrick J.; Chung, Mina K.
Background Atrial fibrillation (AF) has been linked to inflammatory factors and obesity. Epicardial fat is a source of several inflammatory mediators related to the development of coronary artery disease. We hypothesized that periatrial fat may have a similar role in the development of AF. Methods and Results Left atrium (LA) epicardial fat pad thickness was measured in consecutive cardiac CT angiograms performed for coronary artery disease or AF. Patients were grouped by AF burden: no (n=73), paroxysmal (n=60), or persistent (n=36) AF. In a short-axis view at the mid LA, periatrial epicardial fat thickness was measured at the esophagus (LA-ESO), main pulmonary artery, and thoracic aorta; retrosternal fat was measured in axial view (right coronary ostium level). LA area was determined in the 4-chamber view. LA-ESO fat was thicker in patients with persistent AF versus paroxysmal AF (P=0.011) or no AF (P=0.003). LA area was larger in patients with persistent AF than paroxysmal AF (P=0.004) or without AF (P<0.001). LA-ESO was a significant predictor of AF burden even after adjusting for age, body mass index, and LA area (odds ratio, 5.30; 95% confidence interval, 1.39 to 20.24; P=0.015). A propensity score–adjusted multivariable logistic regression that included age, body mass index, LA area, and comorbidities was also performed and the relationship remained statistically significant (P=0.008). Conclusions Increased posterior LA fat thickness appears to be associated with AF burden independent of age, body mass index, or LA area. Further studies are necessary to examine cause and effect, and if inflammatory, paracrine mediators explain this association. PMID:20504944
Kumareswaran, Ramanan; Dorian, Paul
Lone atrial fibrillation is a set of heterogeneous disorders grouped together due to our limited understanding of their pathophysiology. Rate control and rhythm control are two strategies used to treat atrial fibrillation but neither has shown improvement in mortality. Therefore, the goal of treatment in patients with lone atrial fibrillation is to improve health related quality of life. Anti-arrhythmic medications are not well studied in lone atrial fibrillation patient population in randomized controlled fashion. However, inferences can be made from trials that mainly included paroxysmal atrial fibrillation patients. Anti-arrhythmic medications are useful in maintenance of sinus rhythm and probably improve quality of life in lone atrial fibrillation.
Nuryani, N.; Solikhah, M.; Nugoho, A. S.; Afdala, A.; Anzihory, E.
Atrial fibrillation is a serious heart problem originated from the upper chamber of the heart. The common indication of atrial fibrillation is irregularity of R peak-to-R-peak time interval, which is shortly called RR interval. The irregularity could be represented using variance or spread of RR interval. This article presents a system to detect atrial fibrillation using variances. Using clinical data of patients with atrial fibrillation attack, it is shown that the variance of electrocardiographic RR interval are higher during atrial fibrillation, compared to the normal one. Utilizing a simple detection technique and variances of RR intervals, we find a good performance of atrial fibrillation detection.
Márquez, Manlio F
Radiofrequency catheter ablation has emerged as a curative therapy for atrial flutter based on studies demonstrating the role of the cavotricuspid isthmus. With a high rate of success and minimal complications, catheter ablation is the therapy of choice for patients with the common type of atrial flutter. Left atrial flutter, non-cavotricuspid isthmus dependent, and those associated with heart disease have a worst outcome with catheter ablation. Radiofrequency catheter ablation has also emerged as a curative therapy for paroxysmal atrial fibrillation based on studies demonstrating the role of triggering foci in the pulmonary veins for the initiation of atrial fibrillation. Catheter ablation is performed by a transseptal approach using radiofrequency energy at the ostium of each pulmonary vein. Mapping is guided by special catheters. Sequential radiofrequency applications eliminates or dissociates pulmonary vein muscle activity. Although complications exists, this is the only curative method for these patients.
Yamase, Yuichiro; Kato, Kimihiko; Horibe, Hideki; Ueyama, Chikara; Fujimaki, Tetsuo; Oguri, Mitsutoshi; Arai, Masazumi; Watanabe, Sachiro; Murohara, Toyoaki; Yamada, Yoshiji
Recent genome-wide association studies (GWASs) identified various genes and loci that confer susceptibility to coronary artery disease or myocardial infarction among Caucasian populations. As myocardial ischemia is an important risk factor for atrial fibrillation, we hypothesized that certain polymorphisms may contribute to the genetic susceptibility to atrial fibrillation through affecting the susceptibility to coronary artery disease. The aim of the present study was to examine the possible association of atrial fibrillation in Japanese individuals with 29 polymorphisms identified as susceptibility loci for coronary artery disease or myocardial infarction in the meta-analyses of GWASs in Caucasian populations. The study subjects comprised 5,470 Japanese individuals (305 subjects with atrial fibrillation and 5,165 controls). Genotypes for 29 polymorphisms were determined by a method that combines the polymerase chain reaction and sequence-specific oligonucleotide probes with suspension array technology. Comparisons of the allele frequencies by the χ(2) test revealed that rs599839 (G→A) of the proline/serine-rich coiled-coil 1 gene (PSRC1, P=0.0084) and rs11556924 (C→T, Arg363His) of the zinc finger, C3HC-type containing 1 gene (ZC3HC1, P=0.0076) were significantly (P<0.01) associated with atrial fibrillation. Multivariable logistic regression analysis with adjustment for age, gender, body mass index, estimated glomerular filtration rate, and the prevalence of smoking, hypertension, diabetes mellitus, and dyslipidemia revealed that rs599839 (P=0.0043; odds ratio, 1.56; dominant model) and rs11556924 (P=0.0043; odds ratio, 1.93; dominant model) were significantly associated with atrial fibrillation, with the minor G and T alleles, respectively, representing risk factors for this condition. PSRC1 and ZC3HC1 may thus be susceptibility loci for atrial fibrillation in Japanese individuals.
McDivitt, Johnathan D; Barstow, Craig
Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. The prevalence increases with age, especially in the seventh and eighth decades of life. AF also is associated with multiple risk factors and conditions that are managed commonly in family medicine settings, such as hypertension and diabetes. Rhythm control and rate control are primarily equivalent for mortality rate, but patients treated for rhythm control have more hospitalizations; however, rhythm control may be a viable option for select patients. Beta blockers and nondihydropyridine calcium channel blockers can be used to achieve rate control. Pharmacotherapy or electrical cardioversion can be used to achieve rhythm control, and antiarrhythmic drugs are used to maintain sinus rhythm. Catheter ablation is an option for symptomatic patients whose AF is refractory to standard treatment. The CHA2DS2-VASc score should be used to predict the risk of stroke for patients with AF. Patients with nonvalvular AF and a history of stroke or transient ischemic attack or CHA2DS2-VASc scores of 2 or greater should be treated with warfarin or novel oral anticoagulants. Patients with valvular AF should be treated with warfarin.
Currently, interventional treatment modalities for atrial fibrillation chiefly comprise experimental techniques. Among the rate-control procedures, AV-nodal ablation in conjunction with permanent pacemaker implantation and transcatheter radiofrequency modulation of the AV-node are clinically accepted techniques. In contrast, the original corridor operation--which electrically isolates the left and right atrium from the sinus- and AV-node--has been changed over time and ultimately led to the development of the MAZE procedure. Among the procedures for maintenance of sinus rhythm, permanent atrial pacing and bi-atrial pacing may offer an effective--though still experimental--treatment modality in selected patients with vagally mediated or bradycardia-induced atrial fibrillation. Despite the fact that the MAZE procedure is highly effective in restoring sinus rhythm and associated with a reasonably low surgical mortality, the morbidity and complication rate of this procedure are high. Automated transvenous low-energy atrioversion may offer an interesting alternative in the future. However, there remain some significant limitations, such as the pain associated with low-energy shocks, the risk of ventricular fibrillation induction and the cost-benefit issue which needs to be solved before this technique can become clinically applicable. Last but not least, transcatheter radio frequency ablation of atrial fibrillation, a still highly investigational technique, may have the potential to revolutionize interventional therapy of atrial fibrillation in the future. For this to occur, however, the technique still needs significant improvement. In conclusion, although their current impact on clinical practice is rather small, interventional techniques for treatment of atrial fibrillation are rapidly developing and will certainly change our therapeutic strategies in the near future.
Leier, C V; Johnson, T M; Lewis, R P
A patient with coarse atrial fibrillation and a rapid ventricular response developed periods of high grade atrioventricular block interpersed with periods of rapid ventricular conduction after the administration of digitalis and propranolol. Intracardiac atrial recordings showed similar atrial rhythms of high right atrial flutter and left atrial fibrillation. The low right atrial recordings showed flutter during the periods of fast ventricular rates and fibrillation during periods of slower ventricular rates. Images PMID:475927
The author reviews the history of atrial fibrillation, the most common sustained cardiac arrhythmia. The chaotic irregularity of arterial pulse was clearly acknowledged by most of physicians of the ancient China, Egypt and Greece. William Harvey (1578-1657), who first described the circulatory system appropriately, was probably the first to describe fibrillation of the auricles in animals in 1628. The French "clinical pathologist", Jean Baptist de Sénac (1693-1770) was the first who assumed a correlation between "rebellious palpitation" and stenosis of the mitral valve. Robert Adams (1791-1875) also reported in 1827 the association of irregular pulses and mitral stenosis. The discovery of digitalis leaf in 1785 by William Withering (1741-1799) brought relief to patients with atrial fibrillation and congestive heart failure by reducing the ventricular rate. From an analysis of simultaneously recorded arterial and venous pressure curves, the Scottish Sir James Mackenzie (1853-11925) demonstrated that a presystolic wave cannot be seen during "pulsus irregularis perpetuus", a term very first used by Heinrich Ewald Hering (1866-1948). Arthur Cushny (1866-1926) noted the similarity between pulse curves in clinical "delirium cordis" and those in dogs with atrial fibrillation. The first human ECG depicting atrial fibrillation was published by Willem Einthoven (1860-1927) in 1906. The proof of a direct connection between absolute arrhythmia and atrial fibrillation was established by two Viennese physicians, Carl Julius Rothberger and Heinrich Winterberg in 1909. Sir Thomas Lewis (1881-1945), the father of modem electrocardiography, studied electrophysiological characteristics of atrial fibrillation and has shown that its basic perpetuating mechanism is circus movement of electrical impulse (re-entry). After him, the major discoveries relating to the pathophysiology and clinical features of atrial fibrillation in the 20th century stemmed from Karel Frederick Wenckebach
Ricci, Renato Pietro
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.
Pankaala, Mikko; Koivisto, Tero; Lahdenoja, Olli; Kiviniemi, Tuomas; Saraste, Antti; Vasankari, Tuija; Airaksinen, Juhani
In this paper we study the feasibility of seismocardiography (SCG) for the detection of Atrial Fibrillation (AF). In this preclinical study, data acquired from one patient having paroxysmal AF (no other heart diseases) is used to introduce specific changes in SCG signal due to AF. Observed changes and phenomena create a foundation for the development of SCG-based AF detection algorithms. SCG data was recorded from the sternum of an AF patient in dorso-ventral direction while at rest in a supine position using a three-axis high precision MEMS accelerometer simultaneously with a one-lead ECG. In contrast to ECG, the magnitude of beats registered with SCG varies considerably from beat to beat during AF. We show that the magnitude of the beats is not random but is in relation to beat intervals. It is shown that extra indicators for detecting AF become available when SCG data is combined with electrocardiographical (ECG) data; there is a certain behavior in the electromechanical delay characteristic of the AF. It is discussed how all this information can be taken advantage of in the detection of AF. Today electrocardiography (ECG) is the primary method for diagnosing arrhythmias, but there is a growing need for simpler and more convenient method for detecting asymptomatic AF. Given the very small dimensions of modern MEMS accelerometers (2mm×2mm), a reliable MEMS based measurement may provide totally new venues for arrhythmia detection.
Curtis, Anne B
Atrial fibrillation is one of the most common and complex cardiac arrhythmias. Using currently available evidence, leading medical societies have established recommendations for the optimal management of atrial fibrillation. These guidelines have recently been updated by 4 consensus groups: the European Society of Cardiology, the American College of Chest Physicians, the Canadian Cardiovascular Society, and a task force of 3 societies from the United States: the American College of Cardiology Foundation, the American Heart Association, and the Heart Rhythm Society. The present review focused on the similarities and differences among these recently updated guidelines. Key revisions included updated information on newer treatments for rhythm control, treatment options to reduce atrial fibrillation complications, and updated anticoagulant management for thromboprophylaxis.
Bonilla, Ingrid M.; Sridhar, Arun; Györke, Sandor; Cardounel, Arturo J.; Carnes, Cynthia A.
Oxidative stress has been implicated in the pathogenesis of atrial fibrillation. There are multiple systems in the myocardium which contribute to redox homeostasis, and loss of homeostasis can result in oxidative stress. Potential sources of oxidants include nitric oxide synthases (NOS), which normally produce nitric oxide in the heart. Two NOS isoforms (1 and 3) are normally expressed in the heart. During pathologies such as heart failure, there is induction of NOS 2 in multiple cell types in the myocardium. In certain conditions, the NOS enzymes may become uncoupled, shifting from production of nitric oxide to superoxide anion, a potent free radical and oxidant. Multiple lines of evidence suggest a role for NOS in the pathogenesis of atrial fibrillation. Therapeutic approaches to reduce atrial fibrillation by modulation of NOS activity may be beneficial, although further investigation of this strategy is needed. PMID:22536189
You, John J.; Singer, Daniel E.; Howard, Patricia A.; Lane, Deirdre A.; Eckman, Mark H.; Fang, Margaret C.; Hylek, Elaine M.; Schulman, Sam; Go, Alan S.; Hughes, Michael; Spencer, Frederick A.; Manning, Warren J.; Halperin, Jonathan L.
Background: The risk of stroke varies considerably across different groups of patients with atrial fibrillation (AF). Antithrombotic prophylaxis for stroke is associated with an increased risk of bleeding. We provide recommendations for antithrombotic treatment based on net clinical benefit for patients with AF at varying levels of stroke risk and in a number of common clinical scenarios. Methods: We used the methods described in the Methodology for the Development of Antithrombotic Therapy and Prevention of Thrombosis Guidelines: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines article of this supplement. Results: For patients with nonrheumatic AF, including those with paroxysmal AF, who are (1) at low risk of stroke (eg, CHADS2 [congestive heart failure, hypertension, age ≥ 75 years, diabetes mellitus, prior stroke or transient ischemic attack] score of 0), we suggest no therapy rather than antithrombotic therapy, and for patients choosing antithrombotic therapy, we suggest aspirin rather than oral anticoagulation or combination therapy with aspirin and clopidogrel; (2) at intermediate risk of stroke (eg, CHADS2 score of 1), we recommend oral anticoagulation rather than no therapy, and we suggest oral anticoagulation rather than aspirin or combination therapy with aspirin and clopidogrel; and (3) at high risk of stroke (eg, CHADS2 score of ≥ 2), we recommend oral anticoagulation rather than no therapy, aspirin, or combination therapy with aspirin and clopidogrel. Where we recommend or suggest in favor of oral anticoagulation, we suggest dabigatran 150 mg bid rather than adjusted-dose vitamin K antagonist therapy. Conclusions: Oral anticoagulation is the optimal choice of antithrombotic therapy for patients with AF at high risk of stroke (CHADS2 score of ≥ 2). At lower levels of stroke risk, antithrombotic treatment decisions will require a more individualized
Atrial fibrillation (AF) affects millions worldwide. Stroke is the most devastating complication of AF and is associated with a huge disease burden. As a preventive measure, anticoagulant therapy is recommended for most AF patients based on presence of stroke risk factors. For the past six decades warfarin remained the gold standard for stroke prevention in AF (SPAF). However, it is associated with numerous limitations such as a high risk of drug-drug, drug-food interactions and need for frequent INR (2-3) monitoring. Novel oral anticoagulant (NOAC) dabigatran etexilate is a selective, specific, reversible direct thrombin inhibitor that has been approved in India for SPAF and primary venous thromboembolism prevention. The efficacy and safety of dabigatran in AF has been established the "Randomized Evaluation of Long-Term Anticoagulant Therapy (RE-LY)", a randomized clinical trial. RE-LY (n = 18,113) demonstrated that the efficacy of dabigatran 110 mg BID was as good as well controlled warfarin and dabigatran 150 mg BID reduced the risk of ischaemic stroke by 25% (P = 0.03). Till date, 150mg dabigatran is the only NOAC offering a superior reduction in most commonly seen ischemic strokes due to AF compared to warfarin. Additionally, both doses of dabigatran significantly reduced the risk of total bleeds, intracranial, and life threatening bleeds versus warfarin (p < 0.05). Dabigatran has advantages over warfarin including predictable pharmacokinetic/pharmacodynamic profile, minimal drug-drug and no drug-food interactions while no monitoring is needed.The 150 mg dose of dabigatran should be considered in younger patients with a low risk of bleeding and good renal function to achieve a superior ischemic stroke reduction, whereas, the 110 mg dose should be considered in elderly patients, those with mild to moderate renal function or those with high risk of bleeding.
Mikulecky, M; Valachova, A
The most popular periodicities in biology and medicine-the circadians and circannuals-stem undoubtedly from the Earth's rotation and its revolution around the sun. The problem is how to explain the existence of circaseptan, i.e. 5-9-day, and other infradian rhythms. They may correspond to the lunar cycles and their 2nd to 6th harmonics. To test such hypothesis, the calendar dates of 127 attacks of atrial fibrillation in one male subject (M.M.) between 1980 and 1994 were transformed into the days numbered 0-29 for the synodic, and 0-26 for tropic lunar cycle. The daily frequencies obtained in this way were smoothed by moving averages of three successive days each. Considerable fluctuations of frequencies of attacks during both cycles were visible by inspection of the corresponding graphs, called lunar plexograms. Thus, a conspicuous nadir is found under the full moon in the synodic cycle, and a marked peak shortly after the extreme southern position of the moon in the tropic cycle. Halberg's cosinor analysis testing the presence of the 1st to 6th harmonic of either lunar cycle rejected the null hypothesis at the alpha = 0.05 level for all harmonics. Accordingly, the occurrence of attacks was cycling with the period lengths of synodic and tropic lunar cycles, and with those of their 1/2-1/6 period lengths, i.e. with a cluster of approximately circa(di)-septan rhythms. This conclusion is supported by similar findings obtained earlier for various medical and biological events.
Geuzebroek, Guillaume S C; van Amersfoorth, Shirley C M; Hoogendijk, Mark G; Kelder, Johannes C; van Hemel, Norbert M; de Bakker, Jacques M T; Coronel, Ruben
Atrial fibrosis is related to atrial fibrillation but may differ in patients with mitral valve disease or lone atrial fibrillation. Therefore, we studied atrial fibrosis in patients with atrial fibrillation+mitral valve disease or with lone atrial fibrillation and compared it with controls. Left and right atrial appendages amputated during Maze III surgery for lone atrial fibrillation (n=85) or atrial fibrillation+mitral valve disease (n=26) were embedded in paraffin, sectioned, and stained with picrosirius red. Atria from 10 deceased patients without a cardiovascular history served as controls. A total of 1048 images (4-μm sections, 10-fold magnification, 4 images per appendage) were obtained and digitized. The percentage of fibrous tissue was calculated by quantitative morphometry. Irrespective of the presence or absence of atrial fibrillation or mitral valve disease, more fibrous tissue was present in right atrial appendages than in left atrial appendages (12.7%±5.7% vs 8.2%±3.9%; P<.0001). The mean amount of fibrous tissue in the atria was significantly larger in patients with atrial fibrillation+mitral valve disease than in patients with lone AF and controls (13.6%±5.8%, 9.7%±3.2%, and 8.8%±2.4%, respectively; P<.01). No significant differences existed between patients with lone atrial fibrillation and patients without a cardiovascular history (controls). Atria of patients with atrial fibrillation and mitral valve disease have more fibrosis than atria of patients with lone atrial fibrillation. However, patients with lone atrial fibrillation have an equal amount of atrial fibrosis compared with controls. These findings support the notion that fibrosis plays a more important role in the pathogenesis of atrial fibrillation secondary to mitral valve disease than in lone atrial fibrillation and potentially explains the relatively poor success of antiarrhythmic surgery in patients with mitral valve disease. Copyright © 2012 The American Association for
Díez-Manglano, Jesús; Bernabeu-Wittel, Máximo; Barón-Franco, Bosco; Murcia-Zaragoza, José; Fuertes Martín, Aurelio; Alemán, Antonio; Ollero-Baturone, Manuel
To determine the use of oral anticoagulants in polypathological patients with atrial fibrillation and its influence on mortality and loss of functionality. Patients with polypathological patient criteria and atrial fibrillation were included in an observational, prospective and multicenter study. Data on demographic, clinical, functional and sociofamilial characteristics, CHADS2 score, levels of hemoglobin, albumin and creatinine, use of oral anticoagulants and survival and functional status at one year were collected. Five hundred and thirty-two (32.6%) of 1,632 polypathological patients had atrial fibrillation. The stroke risk was high in 505 (94.9%), moderate in 24 (4.5%) and low in 3 (0.6%) patients. Oral anticoagulants were used in 61% of patients with CHADS2 score≥2 and in 37.5% with CHADS2 score=1. Oral anticoagulants were less used in older patients, with more functional and cognitive impairment. Heart failure was associated with more use of oral anticoagulants. There was no difference by the presence of hypertension, diabetes, anemia, renal insufficiency or stroke. In multivariate analysis the use of oral anticoagulants was independently associated with lower age, lower cognitive impairment, absence of hepatic disease and with higher stroke risk. The prescription of oral anticoagulants was independently associated with more survival at one year with no influence on functional status. Oral anticoagulants are underused in polypathological patients with atrial fibrillation despite being associated with more survival. Copyright © 2012 Elsevier España, S.L. All rights reserved.
Raphael, Claire E.
Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia seen in clinical practice with prevalence in excess of 33 million worldwide. Although often asymptomatic and until recently considered a “benign” arrhythmia, it is now appreciated that thromboembolism resulting from AF results in significant morbidity and mortality predominantly due to stroke. Although an arrhythmia more commonly affecting the elderly, AF can also occur in the young. This review focuses on the impact of AF in the younger population and discusses the dilemmas of managing younger patients with AF. PMID:25922764
Kazui, Toshinobu; Henn, Mathew C.; Watanabe, Yoshiyuki; Kovács, Sándor J.; Lawrance, Christopher P.; Greenberg, Jason W.; Moon, Marc; Schuessler, Richard B.; Damiano, Ralph J.
Objective The impact of prolonged episodes of atrial fibrillation on atrial and ventricular function has been incompletely characterized. The purpose of this study was to investigate the influence of atrial fibrillation on left atrial and ventricular function in a rapid paced porcine model of atrial fibrillation. Methods A control group of pigs (group 1, n = 8) underwent left atrial and left ventricular conductance catheter studies and fibrosis analysis. A second group (group 2, n = 8) received a baseline cardiac magnetic resonance imaging to characterize left atrial and left ventricular function. The atria were rapidly paced into atrial fibrillation for 6 weeks followed by cardioversion and cardiac magnetic resonance imaging. Results After 6 weeks of atrial fibrillation, left atrial contractility defined by atrial end-systolic pressure-volume relationship slope was significantly lower in group 2 than in group 1 (1.1 ± 0.5 vs 1.7 ± 1.0; P = .041), whereas compliance from the end-diastolic pressure-volume relationship was unchanged (1.5 ± 0.9 vs 1.6 ± 1.3; P = .733). Compared with baseline, atrial fibrillation resulted in a significantly higher contribution of left atrial reservoir volume to stroke volume (32% vs 17%; P = .005) and lower left atrial booster pump volume contribution to stroke volume (19% vs 28%; P = .029). Atrial fibrillation also significantly increased maximum left atrial volume (206 ± 41 mL vs 90 ± 21 mL; P < .001). Left atrial fibrosis in group 2 was significantly higher than in group 1. Atrial fibrillation decreased left ventricular ejection fraction (29% ± 9% vs 58 ± 8%; P < .001), but left ventricular stroke volume was unchanged. Conclusions In a chronic model of atrial fibrillation, the left atrium demonstrated significant structural remodeling and decreased contractility. These data suggest that early intervention in patients with persistent atrial fibrillation might mitigate against adverse atrial and ventricular structural
Jaakkola, Jussi; Mustonen, Pirjo; Kiviniemi, Tuomas; Hartikainen, Juha E. K.; Palomäki, Antti; Hartikainen, Päivi; Nuotio, Ilpo; Ylitalo, Antti; Airaksinen, K. E. Juhani
Atrial fibrillation may remain undiagnosed until an ischemic stroke occurs. In this retrospective cohort study we assessed the prevalence of ischemic stroke or transient ischemic attack as the first manifestation of atrial fibrillation in 3,623 patients treated for their first ever stroke or transient ischemic attack during 2003–2012. Two groups were formed: patients with a history of atrial fibrillation and patients with new atrial fibrillation diagnosed during hospitalization for stroke or transient ischemic attack. A control group of 781 patients with intracranial hemorrhage was compiled similarly to explore causality between new atrial fibrillation and stroke. The median age of the patients was 78.3 [13.0] years and 2,009 (55.5%) were women. New atrial fibrillation was diagnosed in 753 (20.8%) patients with stroke or transient ischemic attack, compared to 15 (1.9%) with intracranial hemorrhage. Younger age and no history of coronary artery disease or other vascular diseases, heart failure, or hypertension were the independent predictors of new atrial fibrillation detected concomitantly with an ischemic event. Thus, ischemic stroke was the first clinical manifestation of atrial fibrillation in 37% of younger (<75 years) patients with no history of cardiovascular diseases. In conclusion, atrial fibrillation is too often diagnosed only after an ischemic stroke has occurred, especially in middle-aged healthy individuals. New atrial fibrillation seems to be predominantly the cause of the ischemic stroke and not triggered by the acute cerebrovascular event. PMID:27936187
Ferreira, Raquel; Primo, João; Adão, Luís; Gonzaga, Anabela; Gonçalves, Helena; Santos, Rui; Fonseca, Paulo; Santos, José; Gama, Vasco
Cardiac surgery for structural heart disease (often involving the left atrium) and radiofrequency catheter ablation of atrial fibrillation have led to an increased incidence of regular atrial tachycardias, often presenting as atypical flutters. This type of flutter is particularly common after pulmonary vein isolation, especially after extensive atrial ablation including linear lesions and/or defragmentation. The authors describe the case of a 51-year-old man, with no relevant medical history, referred for a cardiology consultation in 2009 for paroxysmal atrial fibrillation. After failure of antiarrhythmic therapy, he underwent catheter ablation, with criteria of acute success. Three years later he again suffered palpitations and atypical atrial flutter was documented. The electrophysiology study confirmed the diagnosis of atypical left flutter and reappearance of electrical activity in the right inferior pulmonary vein. This vein was again ablated successfully and there has been no arrhythmia recurrence to date. In an era of frequent catheter ablation it is essential to understand the mechanism of this arrhythmia and to recognize such atypical flutters. Copyright © 2016 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.
Czick, Maureen E.; Shapter, Christine L.; Silverman, David I.
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
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
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.
Mozo de Rosales, F; Moreno, J; Bodegas, A; Melchor, J C; Fernández LLebrez, L; Aranguren, G
Pregnancy is related to an increased frequency of arrhythmias in asymptomatic patients with Wolff-Parkinson-White syndrome, which might lead to sudden death. A 40-year-old woman, with Wolff-Parkinson-White syndrome which was not diagnosed until pregnancy, presented in the 34th week with an atrial fibrillation, with high risk criteria for ventricular fibrillation. Intravenous ajmaline was given to convert the tachyarrhythmia to sinus rhythm. We obtained an excellent maternal control with no maternal or fetal adverse effects.
Martins, Raphaël P; Mabo, Philippe
Atrial fibrillation (AF) is the most common arrhythmia in clinical practice. Pulmonary veins are a major source of ectopic activities initiating the arrhythmia and the fibrillatory conduction, associating multiple wavelets and high frequency functional reentries called "rotors". AF is responsible for atrial electrophysiological, contractile and structural remodelling, shortening the wavelength, accelerating AF cycle length and sustaining the arrhythmia. A better understanding of the mechanisms responsible for this arrhythmia led to new therapeutic approaches, including ablation, and could eventually lead to the development of new anti-arrhythmic drug agents.
Ramos-González-Serna, Amelia; Mateos-García, M Dolores
Ablation of pulmonary veins for treatment of atrial fibrillation involves applying radiofrequency energy wave by a catheter that causes a circumferential lesion to achieve electrical isolation and voltage drop in the interior. It is mainly applied when there is resistance to treatment and recurrence of symptoms affecting the quality of life of patients. The nurse is an important part of the multidisciplinary team who care for patients who undergo this procedure. The provision of comprehensive nursing care should include nursing procedures prior to, during, and after treatment to ensure the careful and systematic quality required. The aims of this article are: to provide specialised knowledge on the procedure of atrial fibrillation ablation, to describe the preparation of the electrophysiology laboratory, analyse nursing care and develop a standardized care plan for patients on whom this procedure is performed using the NANDA (North American Nursing Association) taxonomy and NIC (Nursing Intervention Classification).
Hernández Olmedo, Miguel; Suárez Fernández, Carmen
Atrial fibrillation is currently a very prevalent disease and it represents one of the most common causes of disabling stroke. Antithrombotic therapies have reduced the incidence of this complication although they pose many limitations and difficulties. As a result, a large number of high risk patients do not receive an appropriate treatment. In recent years, four new oral anticoagulants (NOAC) with relevant advantages in comparison to vitaminK antagonists have been released. Four large phaseiii clinical trials have demonstrated that NOAC are at least as safe and efficacious as warfarin in stroke prevention in non-valve atrial fibrillation patients with moderate-high thrombotic risk, being their main advantage the reduction in intracranial hemorrhage. The arrival of these drugs has caused great expectations in the management of these patients but also new doubts. Lacking data in some subgroups of frail patients, the absence of specific antidotes available and specially their high cost represent nowadays the main limitations for their generalization.
Sukhacheva, T V; Eremeeva, M V; Ibragimova, A G; Vaskovskii, V A; Serov, R A; Revishvili, A Sh
The myocardium of the right and left atrial appendages (auricles) in patients with paroxysmal, persistent, and permanent forms of atrial fibrillation was examined by histological methods and electron microscopy. Isolated atrial amyloidosis was detected in the left (50.0-56.3% patients) and in the right (45.0-55.6% patients) atrial appendages. In all cases, immunohistochemistry revealed atrial natriuretic peptide in fibrillary amyloid deposits. Ultrastructurally, amyloid masses formed clusters of myofibrils 8-10 nm in diameter. They were chaotically located in the extracellular space along the sarcolemma as well as in membrane invaginations, dilated tubules of cardiomyocyte T-tubular system, and vascular walls. Amyloidosis was predominantly observed in women; its degree positively correlated with age of patients and duration of atrial fibrillation but negatively correlated with atrial fibrosis. The study revealed positive (in permanent atrial fibrillation) and negative (in paroxysmal atrial fibrillation) correlation of amyloidosis with myofibril content in atrial cardiomyocytes.
Lipset, Mark A.; Lemery, Jay; Polk, J. D.; Hamilton, Douglas R.
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
Lim, Han S; Zellerhoff, Stephan; Derval, Nicolas; Denis, Arnaud; Yamashita, Seigo; Berte, Benjamin; Mahida, Saagar; Hooks, Darren; Aljefairi, Nora; Shah, Ashok J; Sacher, Frédéric; Hocini, Meleze; Jais, Pierre; Haissaguerre, Michel
Atrial fibrillation (AF) is a dynamic rhythm. Noninvasive mapping overcomes many previous barriers to mapping such a dynamic rhythm, by providing a beat-to-beat, biatrial, panoramic view of the AF process. Catheter ablation of AF drivers guided by noninvasive mapping has yielded promising clinical results and has advanced understanding of the underlying pathophysiologic processes of this common heart rhythm disorder. Copyright © 2015 Elsevier Inc. All rights reserved.
Bulava, Alan; Mokracek, Ales; Hanis, Jiri; Kurfirst, Vojtech; Eisenberger, Martin; Pesl, Ladislav
Background Catheter ablation of persistent atrial fibrillation yields an unsatisfactorily high number of failures. The hybrid approach has recently emerged as a technique that overcomes the limitations of both surgical and catheter procedures alone. Methods and Results We investigated the sequential (staged) hybrid method, which consists of a surgical thoracoscopic radiofrequency ablation procedure followed by radiofrequency catheter ablation 6 to 8 weeks later using the CARTO 3 mapping system. Fifty consecutive patients (mean age 62±7 years, 32 males) with long‐standing persistent atrial fibrillation (41±34 months) and a dilated left atrium (>45 mm) were included and prospectively followed in an unblinded registry. During the electrophysiological part of the study, all 4 pulmonary veins were found to be isolated in 36 (72%) patients and a complete box‐lesion was confirmed in 14 (28%) patients. All gaps were successfully re‐ablated. Twelve months after the completed hybrid ablation, 47 patients (94%) were in normal sinus rhythm (4 patients with paroxysmal atrial fibrillation required propafenone and 1 patient underwent a redo catheter procedure). The majority of arrhythmias recurred during the first 3 months. Beyond 12 months, there were no arrhythmia recurrences detected. The surgical part of the procedure was complicated by 7 (13.7%) major complications, while no serious adverse events were recorded during the radiofrequency catheter part of the procedure. Conclusions The staged hybrid epicardial–endocardial treatment of long‐standing persistent atrial fibrillation seems to be extremely effective in maintenance of normal sinus rhythm compared to radiofrequency catheter or surgical ablation alone. Epicardial ablation alone cannot guarantee durable transmural lesions. Clinical Trial Registration URL: www.ablace.cz Unique identifier: cz‐060520121617 PMID:25809548
Ivers, Noah; Dorian, Paul
Guidelines can be lengthy and complex to apply. We provide a concise summary of important components of outpatient atrial fibrillation management, based on the updated Canadian Cardiovascular Society guidelines. Common questions arising when caring for such patients are addressed, including: what underlying causes should be investigated and treated, how to assess and treat symptoms, how to determine and reduce stroke risk, and when to arrange subspecialty referral. The guidelines emphasize that emergency room visits are rarely necessary and quality of life for most patients with atrial fibrillation can be quite good. The guidelines also clarify that bleeding risk factors should be assessed to identify modifiable issues, rather than as a reason to permanently withhold oral anticoagulant therapy. There is an opportunity to substantially reduce the morbidity and health-system costs related to atrial fibrillation through patient education related to symptom management and adherence to appropriate stroke prevention therapy. Copyright © 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.
Saleem, TS Mohamed; Bharani, K; Chetty, C Madhusudhana; Gauthaman, K
Atrial fibrillation is the most common type of tachyarrhythmia caused by multiple re-entrant wave forms within the atria and bombarding the atrioventricular node several times making it beat in a rapid, disorganized fashion termed “fibrillation”. In atrial fibrillation, atria beat more than 300 times per minute. The arrhythmatous condition needs to be controlled, as humans cannot withstand this rapid and chaotic beating of the heart. New investigational drugs like Dronedarone® are being used. Dronedarone is the most recent antiarrhythmic drugs. It was approved by US-FDA on July 2nd 2009 and is available in the USA as Multaq tablets (400 mg). Dronedarone falls under the category of multiple ion channel blocker. It mainly targets the repolarization currents, making them less active and hence prolonging the action potential duration (APD). Dronedarone also exhibits antiadrenergic activity, thus reducing the pace of the pacemaker. Dronedarone has been proven to be a safer and efficacious AAD, evidenced by both animal and human studies. These studies showed that there was prolongation of the APD and absence of QT interval prolongation with long term administration of the drug. Also there was reduced thyroid hormone receptor expression. Dronedarone is significantly safer and effective in maintaining the sinus rhythm and reducing the ventricular proarrhythmias, justifying it for the long term treatment of atrial fibrillation compared to other antiarrhythmic drugs. PMID:27147833
Many studies have reported that there is no significant difference in survival rate between rhythm control and rate control strategies in combination of with anticoagulation in patients with atrial fibrillation. Even in patients with atrial fibrillation and with heart failure there is no significant difference in survival rate between both strategies. There is no need of strict rate control. In patients with permanent atrial fibrillation, lemient rate control(resting heart rate of below 110 beats per minute) is as effective as strict rate control (< 70 beats per minute) and easier to achieve. Digitalis, beta-blockers and Ca channel blockers are used for rate control treatments. Digitalis is the only drug that has both decreasing ventricular response by suppressing atrioventricular conduction and inotropic effects. However, digitalis can not suppress heart rates during exercise. Beta-blockers and Ca channel blockers can suppress heart rates not only at rest but also during exercise. Ca channel blockers can not be used for patients with heart failure due to reduction in contractility of heart muscle. It has been reported that cardiac function and survival rate can be improved by beta-blockers in patients with heart failure if starting low dose and increasing gradually.
Bozorgmanesh, R; Magdesian, K G; Estell, K E; Stern, J A; Swain, E A; Griffiths, L G
There is limited information on the incidence of clinical signs, concurrent illness and treatment options for atrial fibrillation (AF) in New World Camelids (NWC). Describe clinical signs and outcome of AF in NWC. Eight New World Camelids admitted with AF. A retrospective observational study of camelids diagnosed with AF based on characteristic findings on electrocardiogram (ECG). All animals had an irregularly irregular heart rhythm detected on physical examination and 4 cases had obtunded mentation on admission. Three camelids were diagnosed with AF secondary to oleander intoxication, 3 animals had underlying cardiovascular disease, 1 was diagnosed with lone AF and 1 had AF diagnosed on examination for a urethral obstruction. Five of eight animals survived to discharge and nonsurvivors consisted of animals which died or were euthanized as a result of cardiovascular disease (2/8) or extra-cardiac disease unrelated to the AF (1/8). Atrial fibrillation occurs in NWC in association with cardiovascular disease, extra-cardiac disease or as lone AF. Amiodarone and transthoracic cardioversion were attempted in one llama with lone AF, but were unsuccessful. Atrial fibrillation was recorded in 0.1% of admissions. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.
Razminia, Mansour; Demo, Hany; Arrieta-Garcia, Carlos; D'Silva, Oliver J; Wang, Theodore; Kehoe, Richard F
The conventional method of cryoballoon ablation of atrial fibrillation involves the use of fluoroscopy for visual guidance. The use of fluoroscopy is accompanied by significant radiation risks to the patient and the medical staff. Herein, we report our experience in performing successful nonfluoroscopic pulmonary vein isolation using cryoballoon ablation in 5 consecutive patients with paroxysmal atrial fibrillation. Five consecutive patients with paroxysmal atrial fibrillation underwent cryoballoon ablation for pulmonary vein isolation using a nonfluoroscopic approach. Pre-procedural cardiac computed tomography or cardiac magnetic resonance imaging was not performed in any patient. A total of twenty pulmonary veins were identified and successfully isolated (100%) with the guidance of intracardiac echocardiography and 3-dimensional electroanatomic mapping. No fluoroscopy was used for the procedures. There were no major procedural adverse events. In an unselected group of patients undergoing cryoballoon ablation, a nonfluoroscopic approach is feasible and can be performed safely and effectively while eliminating the risks associated with radiation to both the patient and the medical staff.
Zaman, Junaid A B; Peters, Nicholas S; Narayan, Sanjiv M
Rotors have long been postulated to drive atrial fibrillation, but evidence has been limited to animal models. This changed recently with the demonstration using focal impulse and rotor modulation (FIRM) mapping that rotors act as human atrial fibrillation sources. This mechanistic approach to diagnosing the causes of atrial fibrillation in individual patients has been supported by substantially improved outcomes from FIRM-guided ablation, resulting in increased attention to rotors as therapeutic targets. In this review, we outline the pathophysiology of rotors in animal and in-silico studies of fibrillation, and how this motivated FIRM mapping in humans. We highlight the characteristics of rotors in human atrial fibrillation, now validated by several techniques, with discussion on similar and discrepant findings between techniques. The interventional approaches to eliminate atrial fibrillation rotors are explained and the ablation results in latest studies using FIRM are discussed. We propose that mapping localized sources for human atrial fibrillation, specifically rotors, is moving the field towards a unifying hypothesis that explains several otherwise contradictory observations in atrial fibrillation management. We conclude by suggesting areas of potential research that may reveal more about these critical sites and how these may lead to better and novel treatments for atrial fibrillation.
Csanádi, Zoltán; Fazekas, Tamás; Varró, András
The authors provide an update on non-pharmacological treatment of atrial fibrillation (AF). They emphasize that although antiarrhythmic drugs continue to be first-line therapy for the arrhythmia considered to be a cardiovascular epidemic, clinical research to develop non-pharmacological means of treatment has been unprecedentally intensified during the last decade. Electrical cardioversion is the most successful non-pharmacological method to restore sinus rhythm, also the efficacy and safety of AV node ablation for palliative ventricular rate-controll is established. "Hybrid" therapeutic procedures, involving combinations of pharmacological and non-pharmacological interventions have gained widespread use. Curative transcatheter ablation for arrhythmia prevention is to be considered in case of clinical suggestions that AF is initiated by a primary regular arrhythmia that is amenable to routine catheter ablation (secondary AF). Despite encouraging results, at this point in time, curative catheter ablation for primary AF may offer significant improvement or even cure only for a small subset of patients, mostly young individuals with normal heart, and paroxysmal AF with frequent, symptomatic episodes refractory to multiple antiarrhythmic drugs. These interventions are to be performed in the settings of a clinical research project in some institutions. Regarding pacemaker therapy in case of bradycardia indication, physiologic pacing (AAI or DDD) is associated with significantly lower incidence of atrial fibrillation than ventricular pacing. Large-scale randomized controlled trials are needed to assess the clinical value of specially designed implantable devices to prevent atrial fibrillation in patients with no conventional bradycardia indication. Also, technical optimization and proper clinical evaluation is needed for implantable atrioverters and implantable cardioverter defibrillators capable of atrial cardioversion therapy.
Today management of atrial fibrillation (AF) centers on restoration and maintenance of normal sinus rhythm or control of the ventricular rate response to AF. Current guidelines state that rhythm and rate control strategies should be considered therapeutically equivalent, but recognize that no "one size fits all," an approach consistent with growing recognition of the heterogeneity of AF. As data from the Sotalol Amiodarone Atrial Fibrillation Efficacy Trial clearly demonstrate, conventional antiarrhythmics have a role in highly symptomatic AF accompanied by decreased quality of life. However, for many AF patients such drugs lack efficacy, have potentially serious side effects, and are poorly tolerated. In parallel with the development of more effective and safer antiarrhythmics, nontraditional approaches to prevention and treatment of AF are being explored. Treatments not considered "antiarrhythmic" that may prevent or forestall AF include aggressive antihypertensive therapy with angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, and some, but not all, beta-blockers and calcium channel antagonists, especially when used as adjunctive therapy. Other approaches include statins, steroids, and fish oil to reduce atrial fibrosis and inflammation, and pacemakers to prevent bradycardia-mediated AF and as a pacing preventive strategy in selected patients. Ablative techniques with potential to cure AF are gaining popularity, but are not yet simple, straightforward, and risk-free procedures. In the future, treatment of AF will progress beyond today's focus on AF as a purely electrocardiographic disease toward a patient and context-specific management strategy involving multiple treatment modalities.
Siontis, Konstantinos C; Oral, Hakan
The landscape of the invasive management of atrial fibrillation, the most common sustained arrhythmia in humans, has changed dramatically in the last decade owing to numerous advances in arrhythmia mapping and ablation technologies. The current review critically appraises novel interventional strategies for the treatment of atrial fibrillation with a focus on clinical effectiveness and safety. PMID:27403294
Savoia, Carmine; Sada, Lidia; Volpe, Massimo
Hypertension is one of the major risk factors for atrial fibrillation which in turn is the most prevalent concomitant condition in hypertensive patients. While both these pathological conditions are independent risk factors for stroke, the association of hypertension and atrial fibrillation increases the incidence of disabling strokes. Moreover, documented or silent atrial fibrillation doubles the rate of cardiovascular death. Lowering blood pressure is strongly recommended, particularly for primary stroke prevention. However, a relatively small percentage of hypertensive patients still achieve the recommended blood pressure goals. The management of atrial fibrillation with respect to stroke prevention is changing. New oral anticoagulants represent a major advancement in long-term anticoagulation therapy in non valvular atrial fibrillation. They have several benefits over warfarin, including improved adherence to the anticoagulation therapy. This is an important issue since non-adherence to stroke prevention medications is a risk factor for first and recurrent strokes.
Poposka, Lidija; Boskov, Vladimir; Risteski, Dejan; Taleski, Jane; Georgievska-Ismail, Ljubica
INTRODUCTION: In patients with an implanted pacemaker, asymptomatic atrial fibrillation (AF) is associated with an increased risk of thrombo-embolic complications. There is still no consensus which duration of episodes of atrial fibrillation should be taken as an indicator for inclusion of oral anticoagulation therapy (OAC). MATERIAL AND METHODS: A total of 104 patients who had no AF episodes in the past and have an indication for permanent pacing were included in the study. RESULTS: During an average follow-up of 18 months, 33 of the patients developed episodes of AF. Inclusion of OAC was performed in 17 patients, in whom AF was recorded, although in all patients CHA2DS2-VASc score was ≥ 1. The inclusion of OAC showed a statistically significant correlation with increasing duration of episodes of AF (r = 0.502, p = 0.003). During the follow-up period none of the patients developed thrombo-embolic complication. CONCLUSION: Considering that our group of patients had no thrombo-embolic events, we could conclude that dividing the AF episodes in less than 1% in 24 hours and longer than 1% within 24 hours could be an indicator for decision-making to include OAK if the CHA2DS2-VASc score is ≥ 1. PMID:27335594
Kate, Mahesh; Gioia, Laura; Buck, Brian; Sivakumar, Leka; Jeerakathil, Thomas; Shuaib, Ashfaq; Butcher, Kenneth
Acute ischemic stroke patients are at risk of early recurrence. We tested the feasibility and safety of initiating dabigatran in patients, within 24 hours of minor stroke in patients without atrial fibrillation. Minor stroke patients (National Institutes of Health Stroke Scale score ≤3) without atrial fibrillation and evidence of acute infarction on magnetic resonance imaging were treated with dabigatran. Treatment began within 24 hours of onset and was continued for 30 days. The primary end point was symptomatic hemorrhagic transformation. A total of 53 patients with median (interquartile range) age of 68 (57-77) years and National Institutes of Health Stroke Scale score of 1 (0-2) were enrolled. Baseline diffusion-weighted imaging volume was 0.8 (0.3-2.4) mL. No patients experienced symptomatic hemorrhagic transformation. Three patients had evidence of asymptomatic petechial hemorrhagic transformation on day 7, which remained stable at day 30, while continuing dabigatran. Dabigatran treatment within 24 hours of minor stroke is feasible. A larger randomized trial is required to confirm the safety and efficacy of this treatment approach. URL: http://www.clinicaltrials.gov. Unique identifier: NCT 01769703. © 2015 American Heart Association, Inc.
Cervigón, Raquel; Moreno, Javier; Millet, José; Pérez-Villacastín, Julián; Castells, Francisco
Since the cardiac activity during atrial fibrillation (AF) may be influenced by autonomic modulations, in this study, a novel method to quantify the effects of the most common anesthetic agent (propofol) in AF ablation procedures is introduced. This study has two main objectives: first, to assess whether the sedation earlier to radio frequency ablation affects the arrhythmia itself, and second, to provide new information that contributes to a better understanding of the influence of the autonomic nervous system on AF. The methodology presented is based on the measurement of synchronization and delay indexes between two atrial activations at adjacent intracavitary electrodes. These parameters aim to estimate whether two activations at different sites may be caused by the same propagating wavefront, or otherwise, are the consequence of independent wavefronts. The results showed that the mentioned indexes have a different behavior at both atria: the right atrium becomes more synchronized with propofol administration, whereas the synchronization index decreases at the left atrium.
Patients with valvular heart disease frequently have atrial fibrillation(AF) due to elevated pressure and dilatation of the left and right atria and pulmonary veins. Guidelines for valvular heart disease and AF recommend that surgical treatment for the valvular heart disease should be performed concomitantly with AF surgery. The Full-Maze procedure has evolved into the gold standard of treatment for medically refractory AF. In addition to the pulmonary vein isolation, the right and left atrial incisions of the Full-Maze procedure are designed to block potential macroreentrant pathways. According to the mechanisms of AF with valvular heart disease, the Full-Maze procedure is more effective for the patients than the pulmonary vein isolation alone.
Bachmann, Justin M; Majmudar, Maulik; Tompkins, Christine; Blumenthal, Roger S; Marine, Joseph E
Atrial fibrillation (AF) is a common cardiac arrhythmia with significant morbidity and public health cost. Because of limitations of efficacy and safety of conventional antiarrhythmic agents, alternative therapies for AF are needed. The potential antiarrhythmic properties of lipid-altering therapy, including the 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors and fish oils, are increasingly recognized, particularly in light of their potential anti-inflammatory properties. This review examines the known effects of lipid-altering therapy on atrial arrhythmias in both experimental and clinical settings. Inflammatory states, such as post-cardiac surgery and AF of recent onset, show promise as targets. In contrast, lipid-lowering therapy is less likely to affect longstanding persistent AF. Current recommendations for the use of lipid-altering therapy for prevention and treatment of AF are summarized.
Verma, Atul; 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
Catheter ablation is less successful for persistent atrial fibrillation than for paroxysmal atrial fibrillation. Guidelines suggest that adjuvant substrate modification in addition to pulmonary-vein isolation is required in persistent atrial fibrillation. We randomly assigned 589 patients with persistent atrial fibrillation in a 1:4:4 ratio to ablation with pulmonary-vein isolation alone (67 patients), pulmonary-vein isolation plus ablation of electrograms showing complex fractionated activity (263 patients), or pulmonary-vein isolation plus additional linear ablation across the left atrial roof and mitral valve isthmus (259 patients). The duration of follow-up was 18 months. The primary end point was freedom from any documented recurrence of atrial fibrillation lasting longer than 30 seconds after a single ablation procedure. Procedure time was significantly shorter for pulmonary-vein isolation alone than for the other two procedures (P<0.001). After 18 months, 59% of patients assigned to pulmonary-vein isolation alone were free from recurrent atrial fibrillation, as compared with 49% of patients assigned to pulmonary-vein isolation plus complex electrogram ablation and 46% of patients assigned to pulmonary-vein isolation plus linear ablation (P=0.15). There were also no significant differences among the three groups for the secondary end points, including freedom from atrial fibrillation after two ablation procedures and freedom from any atrial arrhythmia. Complications included tamponade (three patients), stroke or transient ischemic attack (three patients), and atrioesophageal fistula (one patient). Among patients with persistent atrial fibrillation, we found no reduction in the rate of recurrent atrial fibrillation when either linear ablation or ablation of complex fractionated electrograms was performed in addition to pulmonary-vein isolation. (Funded by St. Jude Medical; ClinicalTrials.gov number, NCT01203748.).
Tarver, William J.
Concerns about heart dysrhythmia have been present since the earliest days of the US manned space program. While information about an astronaut's health is general kept private, one of the original seven American astronaut's health status was played out in a very public forum. Donald "Deke" Slayton was removed from the second manned space flight when it was discovered he had idiopathic atrial fibrillation. Referencing the original medical documents, details of how this was discovered and managed from the medical perspective will be reviewed. This is NASA's first heart dysrhythmia case in an astronaut and it proves quite interesting when placed in historic perspective.
Pistoia, Francesca; Sacco, Simona; Tiseo, Cindy; Degan, Diana; Ornello, Raffaele; Carolei, Antonio
The burden of stroke is increasing due to aging population and unhealthy lifestyle habits. The considerable rise in atrial fibrillation (AF) is due to greater diffusion of risk factors and screening programs. The link between AF and ischemic stroke is strong. The subtype most commonly associated with AF is cardioembolic stroke, which is particularly severe and shows the highest rates of mortality and permanent disability. A trend toward a higher prevalence of cardioembolic stroke in high-income countries is probably due to the greater diffusion of AF and the control of atherosclerotic of risk factors.
Mahida, Saagar; Sacher, Frederic; Derval, Nicolas; Berte, Benjamin; Yamashita, Seigo; Hooks, Darren; Denis, Arnaud; Amraoui, Sana; Hocini, Meleze; Haissaguerre, Michel; Jais, Pierre
Over the past few decades, significant progress has been made in understanding the mechanistic basis of atrial fibrillation (AF). One of the most important discoveries in this context has been that pulmonary veins (PV) play a prominent role in the pathogenesis of AF. PV isolation has since become the most widely used technique for treatment of paroxysmal AF. Multiple studies have demonstrated that the electrophysiological and anatomical characteristics of PVs create a proarrhythmogenic substrate. The following review discusses the mechanistic links between PVs and AF. PMID:26835098
Ros, E; Mota, S; Toro, F J; Díaz, A F; Fernández, F J
The objective of the paper is to describe an automatic algorithm for Paroxysmal Atrial Fibrillation (PAF) Detection, based on parameters extracted from ECG traces with no atrial fibrillation episode. The modular automatic classification algorithm for PAF diagnosis is developed and evaluated with different parameter configurations. The database used in this study was provided by Physiobank for The Computers in Cardiology Challenge 2001. Each ECG file in this database was translated into a 48 parameter vector. The modular classification algorithm used for PAF diagnosis was based on the nearest K-neighbours. Several configuration options were evaluated to optimize the classification performance. Different configurations of the proposed modular classification algorithm were tested. The uni-parametric approach achieved a top classification rate value of 76%. A multi-parametric approach was configured using the 5 parameters with highest discrimination power, and a top classification rate of 80% was achieved; different functions to typify the parameters were tested. Finally, two automatic parametric scanning strategies, Forward and Backward methods, were adopted. The results obtained with these approaches achieved a top classification rate of 92%. A modular classification algorithm based on the nearest K-neighbours was designed. The classification performance of the algorithm was evaluated using different parameter configurations, typification functions and number of K-neighbors. The automatic parametric scanning techniques achieved much better results than previously tested configurations.
Mina Md Facc Fhrs, Adel F; L Warnecke Pa-C, Nicholas
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
Thomas, S P; Boyd, A C; Aggarwal, G; Jin, Y; Ross, D L
Transvenous catheter ablation for the treatment of atrial fibrillation is an evolving technique. The purpose of this study was to identify subgroups of patients most likely to benefit from pulmonary vein electrical isolation. Patients with symptomatic atrial fibrillation resistant to pharmacological therapy were studied. Mapping-guided segmental application of radio-frequency energy was used to electrically isolate the pulmonary veins in 74 patients. Ischaemic or dilated cardiomyopathy was present in 34% of patients. Atrial fibrillation had been present for a mean time (+/- standard deviation) of 6.6 +/- 6.1 years. It was paroxysmal in 53 patients (72%). The mean number of procedures was 1.6/patient. After 6 +/- 6 months, 73% of patients (54/74) were in sinus rhythm. Thirteen of those in sinus rhythm were using anti-arrhythmic medications (25%). Recurrence of atrial fibrillation soon after pulmonary vein isolation occurred in 50%. Patients with persistent/permanent atrial fibrillation were less likely to be in sinus rhythm at follow up (11/21 (52%) vs 43/53 (81%); P = 0.01). However, the rate of early recurrence was similar in the intermittent and the persistent/permanent groups (26/53 (49%) vs 11/21(52%), respectively; P-value not significant). Patients with persistent atrial fibrillation were more likely to experience a recurrence of atrial fibril-lation (89%; P = 0.04). No other baseline factors predicted procedural success. Cardiac tamponade occurred in two patients and moderate pulmonary vein stenosis (>50% diameter narrowing) occurred in three patients. Pulmonary vein isolation is an effective curative treatment for a broad group of patients with atrial fibrillation. However, the procedure is only suitable for patients with problematic atrial fibrillation resistant to other therapies because of the small risk of serious complications.
... Treatment of Atrial Fibrillation; Guidance for Industry and Food and Drug Administration Staff; Availability... Ablation Devices for Treatment of Atrial Fibrillation.'' This guidance provides FDA's recommendations on clinical trial designs for surgical ablation devices intended for the treatment of atrial...
Floria, Mariana; Drug, Vasile Liviu
We have read with interest the paper by Roman C. and colleagues discussing the relationship between gastroesophageal reflux disease and atrial fibrillation. The review is presenting the available evidence for the common pathogenic mechanisms. However, from a cardiologist perspective, some available data were not highlighted in the review, cardiovascular involvement in gastroesophageal reflux is less assessed. Hypertension, obesity or diabetes mellitus are substrate for left atrial remodeling that initiate and sustained atrial fibrillation development. One of the pathophysiologic mechanisms in atrial fibrillation is the presence of a trigger. Gastroesophageal reflux could be only a trigger for this arrhythmia. We believe that atrial fibrillation should be considered as possible extraesophageal syndrome in the gastroesophageal reflux classification.
Olesen, Jonas Bjerring; Gislason, Gunnar Hilmar; Torp-Pedersen, Christian; Lip, Gregory Y H
This article provides an overview of (i) the risk of stroke associated with vascular disease (acute coronary syndromes and peripheral artery disease) in patients with atrial fibrillation, (ii) the frequent coexistence of vascular disease in patients with atrial fibrillation and, (iii) the cardiovascular risk associated with the coexisting of the two diseases. The literature on this topic is relatively sparse, and we discuss results from both clinical trials and observational studies. There is a clear indication of an increased stroke risk associated with vascular disease in patients with atrial fibrillation. Indeed, patients with atrial fibrillation often had coexisting vascular disease (around 18%), and the combination of the two diseases substantially increases the risk of future cardiovascular events. The increased risk associated with peripheral artery disease in atrial fibrillation is even more pronounced. Patients with atrial fibrillation and stable vascular disease should be treated with oral anticoagulation only, although when these patients present with acute coronary syndrome and/or undergo coronary stenting, concomitant treatment with antiplatelet drugs is indicated. To guide antithrombotic management in patients with atrial fibrillation, several stroke and bleeding risk prediction schemes have been developed. © 2012 Wiley Periodicals, Inc.
Safaei, Nasser; Montazerghaem, Hossein; Azarfarin, Rasoul; Alizadehasl, Azin; Alikhah, Hossein
Atrial Fibrillation (AF) is the most common cardiac arrhythmia which represents a major public health problem. The main purpose of this research is to evaluate the Radiofrequency (RF) ablation effects in the patients with chronic AF scheduled for cardiac surgery because of different heart diseases. The descriptive and prospective study was conducted on 60 patients with AF scheduled for surgery along with RF ablation. The data were collected by questionnaire and included: patients' age, sex, NYHA class, operation type, past medical history, type and cause of valvular heart disease, preoperative ECG (electrocardiogram), duration of surgery, clamping time, cardiopulmonary bypass, and RF ablation time. RF ablation was followed by the main operation. The follow up examination, ECG, and echocardiography were performed 3 and 6 months after operation. The mean age of patients was 48±10 years (18-71 years). Forty one patients had permanent AF and 19 had the persistent AF. The left ventricular ejection fraction was 48.27±9.75 percent before operation, and reached to 56.27±7.87 percent after the surgery (P<0.001). The mean NYHA class before the surgery was 2.83±0.68 which decreased to 1.34±0.46 6 months after the surgery with RF ablation (P<0.001). One patient (1.6%) died after surgery. Complete relief and freedom from AF recurrence was observed in 70% of patients in the mean follow up in 7 months after the surgery. The sinus rhythm with efficient atrial contraction was established in 100% of discharged patients. RF ablation is an effective procedure to cure atrial fibrillation in patients undergoing cardiac surgeries.
Atrial fibrillation (AF) remains the most common cardiac arrhythmia, affecting nearly 2% of the general population worldwide. Minimally invasive surgical ablation remains one of the most dynamically evolving fields of modern cardiac surgery. While there are more than a dozen issues driving this development, two seem to play the most important role: first, there is lack of evidence supporting percutaneous catheter based approach to treat patients with persistent and long-standing persistent AF. Paucity of this data offers surgical community unparalleled opportunity to challenge guidelines and change indications for surgical intervention. Large, multicenter prospective clinical studies are therefore of utmost importance, as well as honest, clear data reporting. Second, a collaborative methodology started a long-awaited debate on a Heart Team approach to AF, similar to the debate on coronary artery disease and transcatheter valves. Appropriate patient selection and tailored treatment options will most certainly result in better outcomes and patient satisfaction, coupled with appropriate use of always-limited institutional resources. The aim of this review, unlike other reviews of minimally invasive surgical ablation, is to present medical professionals with two distinctly different, approaches. The first one is purely surgical, Standalone surgical isolation of the pulmonary veins using bipolar energy source with concomitant amputation of the left atrial appendage—a method of choice in one of the most important clinical trials on AF—The Atrial Fibrillation Catheter Ablation Versus Surgical Ablation Treatment (FAST) Trial. The second one represents the most complex approach to this problem: a multidisciplinary, combined effort of a cardiac surgeon and electrophysiologist. The Convergent Procedure, which includes both endocardial and epicardial unipolar ablation bonds together minimally invasive endoscopic surgery with electroanatomical mapping, to deliver best of
Wijesurendra, Rohan S.; Casadei, Barbara
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. PMID:25587048
Wijesurendra, Rohan S; Casadei, Barbara
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.
Goyal, Sandeep K; Sharma, Abhishek
Atrial fibrillation (AF) is a common arrhythmia with rising incidence. Obstructive sleep apnea (OSA) is prevalent among patients with AF. This observation has prompted significant research in understanding the relationship between OSA and AF. Multiple studies support a role of OSA in the initiation and progression of AF. This association has been independent of obesity, body mass index and hypertension. Instability of autonomic tone and wide swings in intrathoracic pressure are seen in OSA. These have been mechanistically linked to initiation of AF in OSA patients by lowering atrial effective refractory period, promoting pulmonary vein discharges and atrial dilation. OSA not only promotes initiation of AF but also makes management of AF difficult. Drug therapy and electrical cardioversion for AF are less successful in presence of OSA. There has been higher rate of early and overall recurrence after catheter ablation of AF in patients with OSA. Treatment of OSA with continuous positive airway pressure has been shown to improve control of AF. However, additional studies are needed to establish a stronger relationship between OSA treatment and success of AF therapies. There should be heightened suspicion of OSA in patients with AF. There is a need for guidelines to screen for OSA as a part of AF management. PMID:23802045
Petrėnas, Andrius; Sörnmo, Leif; Lukoševičius, Arūnas; Marozas, Vaidotas
This work introduces a novel approach to the detection of brief episodes of paroxysmal atrial fibrillation (PAF). The proposed detector is based on four parameters which characterize RR interval irregularity, P-wave absence, f-wave presence, and noise level, of which the latter three are determined from a signal produced by an echo state network. The parameters are used for fuzzy logic classification where the decisions involve information on prevailing signal quality; no training is required. The performance is evaluated on a large set of test signals with brief episodes of PAF. The results show that episodes with as few as five beats can be reliably detected with an accuracy of 0.88, compared to 0.82 for a detector based on rhythm information only (the coefficient of sample entropy); this difference in accuracy increases when atrial premature beats are present. The results also show that the performance remains essentially unchanged at noise levels up to [Formula: see text] RMS. It is concluded that the combination of information on ventricular activity, atrial activity, and noise leads to substantial improvement when detecting brief episodes of PAF.
Kamel, Hooman; Okin, Peter M.; Longstreth, W. T.; Elkind, Mitchell S.V.; Soliman, Elsayed Z.
Atrial fibrillation (AF) has long been associated with a heightened risk of ischemic stroke and systemic thromboembolism, but recent data require a re-evaluation of our understanding of the nature of this relationship. New findings about the temporal connection between AF and stroke, alongside evidence linking markers of left atrial abnormalities with stroke in the absence of apparent AF, suggest that left atrial thromboembolism may occur even without AF. These observations undermine the hypothesis that the dysrhythmia that defines AF is necessary and sufficient to cause thromboembolism. In this commentary, we instead suggest that the substrate for thromboembolism may often be the anatomic and physiological atrial derangements associated with AF. Therefore, our understanding of cardioembolic stroke may be more complete if we shift our representation of its origin from AF to the concept of atrial cardiopathy. PMID:26021638
Hussein, Ayman A.; Saliba, Walid I.; Barakat, Amr; Bassiouny, Mohammed; Chamsi-Pasha, Mohammed; Al-Bawardy, Rasha; Hakim, Ali; Tarakji, Khaldoun; Baranowski, Bryan; Cantillon, Daniel; Dresing, Thomas; Tchou, Patrick; Martin, David O.; Varma, Niraj; Bhargava, Mandeep; Callahan, Thomas; Niebauer, Mark; Kanj, Mohamed; Chung, Mina; Natale, Andrea; Lindsay, Bruce D.; Wazni, Oussama M.
Background Various ablation strategies of persistent atrial fibrillation (PersAF) have had disappointing outcomes, despite concerted clinical and research efforts, which could reflect progressive atrial fibrillation–related atrial remodeling. Methods and Results Two-year outcomes were assessed in 1241 consecutive patients undergoing first-time ablation of PersAF (2005–2012). The time intervals between the first diagnosis of PersAF and the ablation procedures were determined. Patients had echocardiograms and measures of B-type natriuretic peptide and C-reactive protein before the procedures. The median diagnosis-to-ablation time was 3 years (25th–75th percentiles 1–6.5). With longer diagnosis-to-ablation time (based on quartiles), there was a significant increase in recurrence rates in addition to an increase in B-type natriuretic peptide levels (P=0.01), C-reactive protein levels (P<0.0001), and left atrial size (P=0.03). The arrhythmia recurrence rates over 2 years were 33.6%, 52.6%, 57.1%, and 54.6% in the first, second, third, and fourth quartiles, respectively (Pcategorical<0.0001). In Cox Proportional Hazard analyses, B-type natriuretic peptide levels, C-reactive protein levels, and left atrial size were associated with arrhythmia recurrence. The diagnosis-to-ablation time had the strongest association with the ablation outcomes which persisted in multivariable Cox analyzes (hazard ratio for recurrence per +1Log diagnosis-to-ablation time 1.27, 95% confidence interval 1.14–1.43; P<0.0001; hazard ratio fourth versus first quartile 2.44, 95% confidence interval 1.68–3.65; Pcategorical<0.0001). Conclusions In patients with PersAF undergoing ablation, the time interval between the first diagnosis of PersAF and the catheter ablation procedure had a strong association with the ablation outcomes, such as shorter diagnosis-to-ablation times were associated with better outcomes and in direct association with markers of atrial remodeling. PMID:26763227
De Bortoli, Alessandro; Shi, Li-Bin; Ohm, Ole-Jørgen; Hoff, Per Ivar; Schuster, Peter; Solheim, Eivind; Chen, Jian
We sought to investigate the incidence of atrial fibrillation after catheter ablation for typical atrial flutter and to determine the predictors for symptomatic atrial fibrillation that required a further additional dedicated ablation procedure. 127 patients underwent elective cavotricuspid isthmus ablation with the indication of symptomatic, typical atrial flutter. The occurrence of atrial flutter, atrial fibrillation, cerebrovascular events and the need for additional ablation procedures for symptomatic atrial fibrillation was assessed during long-term follow-up. The majority of patients (70%) manifested atrial fibrillation during a follow-up period of 68 ± 24 months, and a significant proportion (42%) underwent one or multiple atrial fibrillation ablation procedures after an average of 26 months from the index procedure. Recurrence of typical atrial flutter was rare. Ten patients (8%) suffered cerebrovascular events. Earlier documentation of atrial fibrillation (OR 3.53), previous use of flecainide (OR 3.33) and left atrial diameter (OR 2.96) independently predicted occurrence of atrial fibrillation during the follow-up. A combination of pre- and intra-procedural documentation of atrial fibrillation (OR 3.81) and previous use of flecainide (OR 2.43) independently predicted additional atrial fibrillation ablation. Atrial fibrillation occurred in the majority of patients after ablation for typical atrial flutter and 42% of them required an additional dedicated ablation procedure. Pre- and intraprocedural documentation of atrial fibrillation together with previous use of flecainide independently predicted atrial fibrillation occurrence and a need for additional ablation. Anticoagulation treatment should be continued in high-risk patients in spite of clinical disappearance of atrial flutter.
Mead, G E; Elder, A T; Flapan, A D; Kelman, A
Atrial fibrillation increases stroke risk and adversely affects cardiovascular haemodynamics. Electrical cardioversion may, by restoring sinus rhythm, improve cardiovascular haemodynamics, reduce the risk of stroke, and obviate the need for long-term anticoagulation. To assess the effects of electrical cardioversion of atrial fibrillation or flutter on the risk of thromboembolic events, strokes and mortality (primary outcomes), the rate of cognitive decline, quality of life, the use of anticoagulants and the risk of re-hospitalisation (secondary outcomes) in adults (>18 years). We searched the Cochrane CENTRAL Register of Controlled Trials (1967 to May 2004), MEDLINE (1966 to May 2004), Embase (1980 to May 2004), CINAHL (1982 to May 2004), proceedings of the American College of Cardiology (published in Journal of the American College of Cardiology 1983 to 2003), www.trialscentral.org, www.controlled-trials.com and reference lists of articles. We hand-searched the indexes of the Proceedings of the British Cardiac Society published in British Heart Journal (1980 to 1995) and in Heart (1995 to 2002); proceedings of the European Congress of Cardiology and meetings of the Joint Working Groups of the European Society of Cardiology (published in European Heart Journal 1983-2003); scientific sessions of the American Heart Association (published in Circulation 1990-2003). Personal contact was made with experts. Randomised controlled trial or controlled clinical trials of electrical cardioversion plus 'usual care' versus 'usual care' only, where 'usual care' included any combination of anticoagulants, antiplatelet drugs and drugs for 'rate control'. We excluded trials which used pharmacological cardioversion as the first intervention, and trials of new onset atrial fibrillation after cardiac surgery. There were no language restrictions. For dichotomous data, odds ratios were calculated; and for continuous data, the weighted mean difference was calculated. We found three
Patel, Manesh R; Mahaffey, Kenneth W; Garg, Jyotsna; Pan, Guohua; Singer, Daniel E; Hacke, Werner; Breithardt, Günter; Halperin, Jonathan L; Hankey, Graeme J; Piccini, Jonathan P; Becker, Richard C; Nessel, Christopher C; Paolini, John F; Berkowitz, Scott D; Fox, Keith A A; Califf, Robert M
The use of warfarin reduces the rate of ischemic stroke in patients with atrial fibrillation but requires frequent monitoring and dose adjustment. Rivaroxaban, an oral factor Xa inhibitor, may provide more consistent and predictable anticoagulation than warfarin. In a double-blind trial, we randomly assigned 14,264 patients with nonvalvular atrial fibrillation who were at increased risk for stroke to receive either rivaroxaban (at a daily dose of 20 mg) or dose-adjusted warfarin. The per-protocol, as-treated primary analysis was designed to determine whether rivaroxaban was noninferior to warfarin for the primary end point of stroke or systemic embolism. In the primary analysis, the primary end point occurred in 188 patients in the rivaroxaban group (1.7% per year) and in 241 in the warfarin group (2.2% per year) (hazard ratio in the rivaroxaban group, 0.79; 95% confidence interval [CI], 0.66 to 0.96; P<0.001 for noninferiority). In the intention-to-treat analysis, the primary end point occurred in 269 patients in the rivaroxaban group (2.1% per year) and in 306 patients in the warfarin group (2.4% per year) (hazard ratio, 0.88; 95% CI, 0.74 to 1.03; P<0.001 for noninferiority; P=0.12 for superiority). Major and nonmajor clinically relevant bleeding occurred in 1475 patients in the rivaroxaban group (14.9% per year) and in 1449 in the warfarin group (14.5% per year) (hazard ratio, 1.03; 95% CI, 0.96 to 1.11; P=0.44), with significant reductions in intracranial hemorrhage (0.5% vs. 0.7%, P=0.02) and fatal bleeding (0.2% vs. 0.5%, P=0.003) in the rivaroxaban group. In patients with atrial fibrillation, rivaroxaban was noninferior to warfarin for the prevention of stroke or systemic embolism. There was no significant between-group difference in the risk of major bleeding, although intracranial and fatal bleeding occurred less frequently in the rivaroxaban group. (Funded by Johnson & Johnson and Bayer; ROCKET AF ClinicalTrials.gov number, NCT00403767.).
Connolly, Stuart J; Eikelboom, John; Joyner, Campbell; Diener, Hans-Christoph; Hart, Robert; Golitsyn, Sergey; Flaker, Greg; Avezum, Alvaro; Hohnloser, Stefan H; Diaz, Rafael; Talajic, Mario; Zhu, Jun; Pais, Prem; Budaj, Andrzej; Parkhomenko, Alexander; Jansky, Petr; Commerford, Patrick; Tan, Ru San; Sim, Kui-Hian; Lewis, Basil S; Van Mieghem, Walter; Lip, Gregory Y H; Kim, Jae Hyung; Lanas-Zanetti, Fernando; Gonzalez-Hermosillo, Antonio; Dans, Antonio L; Munawar, Muhammad; O'Donnell, Martin; Lawrence, John; Lewis, Gayle; Afzal, Rizwan; Yusuf, Salim
Vitamin K antagonists have been shown to prevent stroke in patients with atrial fibrillation. However, many patients are not suitable candidates for or are unwilling to receive vitamin K antagonist therapy, and these patients have a high risk of stroke. Apixaban, a novel factor Xa inhibitor, may be an alternative treatment for such patients. In a double-blind study, we randomly assigned 5599 patients with atrial fibrillation who were at increased risk for stroke and for whom vitamin K antagonist therapy was unsuitable to receive apixaban (at a dose of 5 mg twice daily) or aspirin (81 to 324 mg per day), to determine whether apixaban was superior. The mean follow up period was 1.1 years. The primary outcome was the occurrence of stroke or systemic embolism. Before enrollment, 40% of the patients had used a vitamin K antagonist. The data and safety monitoring board recommended early termination of the study because of a clear benefit in favor of apixaban. There were 51 primary outcome events (1.6% per year) among patients assigned to apixaban and 113 (3.7% per year) among those assigned to aspirin (hazard ratio with apixaban, 0.45; 95% confidence interval [CI], 0.32 to 0.62; P<0.001). The rates of death were 3.5% per year in the apixaban group and 4.4% per year in the aspirin group (hazard ratio, 0.79; 95% CI, 0.62 to 1.02; P=0.07). There were 44 cases of major bleeding (1.4% per year) in the apixaban group and 39 (1.2% per year) in the aspirin group (hazard ratio with apixaban, 1.13; 95% CI, 0.74 to 1.75; P=0.57); there were 11 cases of intracranial bleeding with apixaban and 13 with aspirin. The risk of a first hospitalization for cardiovascular causes was reduced with apixaban as compared with aspirin (12.6% per year vs. 15.9% per year, P<0.001). The treatment effects were consistent among important subgroups. In patients with atrial fibrillation for whom vitamin K antagonist therapy was unsuitable, apixaban reduced the risk of stroke or systemic embolism without
Ricard, P; Socas, A G; Taramasco, V; Guenoun, M; Lévy, S
The efficacy and safety of low internal cardioversion for the reduction of atrial fibrillation was assessed prospectively in 104 consecutive patients. Sixty-two patients had chronic atrial fibrillation (Group I). 16 patients had paroxysmal atrial fibrillation (Group II) and 26 patients had induced atrial fibrillation (Group III). The average duration of the current episode of atrial fibrillation was 9 +/- 19 months in Group I, 4 +/- 2 days in Group II and 18 +/- 7 minutes in Group III. Two intracardiac defibrillation catheters were used, one (the cathode) in the right atrium and the other in the coronary sinus or left branch of the pulmonary artery (anode). These catheters were connected to an external defibrillator delivering biphasic 3/3 ms shocks with a voltage which could be programmed from 10 to 400 volts. The shocks were synchronised on the R wave. Sinus rhythm was restored in 44 of the 62 patients in Group I (70%), 12 of the 16 patients in Group II (75%) and 20 of the 26 patients in Group III (77%). The average voltages and energies restoring sinus rhythm were 300 +/- 68 volts and 3.5 +/- 1.5 joules respectively in Group I, 245 +/- 72 volts and 2.0 +/- 2.9 joules in Group II, and 270 +/- 67 volts and 2.6 +/- 1.2 joules in Group III. These results show that the energy required to restore sinus rhythm is significantly greater in patients with chronic atrial fibrillation than in patients with paroxysmal or induced atrial fibrillation. There were no ventricular proarrhythmic effects in the 686 shocks synchronised on the R wave. This study shows that internal cardioversion of atrial fibrillation is feasible with low energies under simple sedation. These results support the concept of an implantable atrial defibrillator.
Compostella, Leonida; Russo, Nicola; D’Onofrio, Augusto; Setzu, Tiziana; Compostella, Caterina; Bottio, Tomaso; Gerosa, Gino; Bellotto, Fabio
Introduction Complete denervation of transplanted heart exerts protective effect against postoperative atrial fibrillation; various degrees of autonomic denervation appear also after transection of ascending aorta during surgery for aortic aneurysm. Objective This study aimed to evaluate if the level of cardiac denervation obtained by resection of ascending aorta could exert any effect on postoperative atrial fibrillation incidence. Methods We retrospectively analysed the clinical records of 67 patients submitted to graft replacement of ascending aorta (group A) and 132 with aortic valve replacement (group B); all episodes of postoperative atrial fibrillation occurred during the 1-month follow-up have been reported. Heart Rate Variability parameters were obtained from a 24-h Holter recording; clinical, echocardiographic and treatment data were also evaluated. Results Overall, 45% of patients (group A 43%, group B 46%) presented at least one episode of postoperative atrial fibrillation. Older age (but not gender, abnormal glucose tolerance, ejection fraction, left atrial diameter) was correlated with incidence of postoperative atrial fibrillation. Only among a subgroup of patients with aortic transection and signs of greater autonomic derangement (heart rate variability parameters below the median and mean heart rate over the 75th percentile), possibly indicating more profound autonomic denervation, a lower incidence of postoperative atrial fibrillation was observed (22% vs. 54%). Conclusion Transection of ascending aorta for repair of an aortic aneurysm did not confer any significant protective effect from postoperative atrial fibrillation in comparison to patients with intact ascending aorta. It could be speculated that a limited and heterogeneous cardiac denervation was produced by the intervention, creating an eletrophysiological substrate for the high incidence of postoperative atrial fibrillation observed. PMID:25859868
Zeus, Tobias; Kelm, Malte; Bode, Christoph
Thrombo-embolic prophylaxis is a key element within the therapy of atrial fibrillation/atrial flutter. Besides new oral anticoagulants the concept of left atrial appendage occlusion has approved to be a good alternative option, especially in patients with increased risk of bleeding.
Gourraud, Jean-Baptiste; Andrade, Jason G; Macle, Laurent
The invasive management of atrial fibrillation (AF) has been considerably changed by the identification of major sites of AF initiation and/or maintenance within the pulmonary vein antra. Percutaneous catheter ablation of these targets has become the standard of care for sustained maintenance of sinus rhythm. Long-term failure of ablation is related to an inability to create a durable transmural lesion or to identify all of the non-pulmonary vein arrhythmia triggers. Pharmacological challenges during catheter ablation have been suggested to improve outcomes in both paroxysmal and persistent AF. Herein we review the mechanism and evidence for the use of pharmacological adjuncts during the catheter ablation of AF. PMID:28116081
Alonso, Alvaro; Arenas de Larriva, Antonio P.
Atrial fibrillation (AF) is a common cardiac arrhythmia. Growing evidence supports a role for AF as a risk factor for cognitive decline and dementia. In this review, we summarize epidemiologic observations linking AF with cognitive outcomes, describe potential mechanisms, and explore the impact of AF treatments on cognitive decline and dementia. Community-based, observational studies show a consistent higher rate of cognitive decline and risk of dementia in persons with AF. These associations are partly due to the increased risk of clinical stroke in AF, but other mechanisms, including incidence of silent cerebral infarcts, microbleeds, and cerebral hypoperfusion, are likely additional contributors. Adequate oral anticoagulation and improved management of the overall cardiovascular risk profile in persons with AF offer the promise of reducing the impact of AF on cognitive decline and dementia. PMID:27547248
Berisso, Massimo Zoni; Caruso, Davide
In the last two decades atrial fibrillation (AF) has become one of the most important public health problems and a significant cause of increasing healthcare costs in developed countries. The prevalence of AF is ever increasing, and at present, in Italy, it is twice higher (1.85%) than that reported in the past decade. In addition, the ratio of AF frequency among males and females in each age subgroup is always >1.2. In the real world, the commonest AF treatment strategy is "rate control" accounting for 51-56% of all AF patients. Anticoagulant therapy is still underused, in particular among several selected AF patient subgroups. The present findings suggest the need for improving AF patient management through ad hoc educational programs.
Sra, Jasbir; Akhtar, Masood
Atrial fibrillation (AF) is a common arrhythmia. Although significant work still needs to be done, recent advances in understanding the mechanism of AF have led to the development of elegant catheter mapping techniques for ablation of AF. These improved mapping techniques are complemented by an evolution in various imaging and navigational technologies, several of which can now be combined in a process called registration, so that the physician no longer needs to rely solely on a mental image of the anatomy of the left atrium and the pulmonary vein while attempting to ablate the region. Ongoing advances in mapping technique will increase safety and efficacy and it is likely that AF ablation will become the first-line therapy in most patients with this complicated arrhythmia.
How, Choon How
Anticoagulation therapy is effective in preventing primary and secondary thromboembolic events due to atrial fibrillation. Warfarin, which was approved by the United States in 1954, was the only long-term oral anticoagulation therapy till the approval of dabigatran in 2010, and of rivaroxaban and other direct factor Xa inhibitors from 2011, forming a group known as novel oral anticoagulants (NOAC). NOAC have fewer food and drug interactions compared to warfarin; hence, the patient will require fewer clinic visits. However, the short half-life of NOAC means that twice-a-day dosing is needed and there is higher risk of a prothrombotic state when doses are missed. Other disadvantages are the lack of long-term data on NOAC, their high cost and the current lack of locally available antidotes. PMID:26702159
Non-vitamin K antagonist (VKA) oral anticoagulants (NOACs) have emerged as alternatives to VKAs for the prevention of stroke in patients with non-valvular atrial fibrillation. Four NOACS: dabigatran, apixaban, rivaroxaban and edoxaban, have received regulatory approval in Europe from the European Medicines Agency. Numerous factors can influence the decision to prescribe a NOAC, the most important of which are assessment of stroke and bleeding risks. Given the variation in design of the pivotal phase III clinical trials investigating the efficacy and safety of NOACs, and in the absence of head-to-head comparative data, it is impossible to recommend one NOAC over the other. However, NOACS offer the opportunity for individualised therapy based on factors such as renal function, age or patient/doctor preference for once- or twice-daily dosing regimens. Dose reduction of some NOACS should be considered in at-risk patient populations. PMID:27617088
Wells, Gretchen L.; Morris, Peter E.
Background Although the mortality rate among patients with sepsis is declining, the incidence of both sepsis and sepsis-related deaths is increasing, likely due to its presence in a growing elderly population. As atrial fibrillation is more common in the elderly, we hypothesize that its presence will be associated with greater mortality among patients with sepsis. Methods The Medical Intensive Care Unit (MICU) database of a large tertiary care medical center was queried for sepsis-related codes and atrial fibrillation. Results Atrial fibrillation was associated with older age and a higher mortality in this series of patients with sepsis. Conclusions Whether atrial fibrillation is a marker of disease severity or contributes to mortality is uncertain. Further studies are necessary to determine optimal management.
Littrell, Rachel; Flaker, Greg
Until recently, pharmaceutical options for stroke prevention in atrial fibrillation were restricted to aspirin or vitamin K antagonist therapy. In recent years development has been underway for alternatives. Apixaban, a direct Factor Xa inhibitor, is orally dosed, target selective and has few known drug or food interactions. As such, it is a member of a new generation of anticoagulants expected to revolutionize the way we approach anticoagulation for stroke prevention in atrial fibrillation. Apixaban has been studied in Phase II and Phase III trials for a variety of indications. The AVERROES trial established apixaban as superior to aspirin for stroke reduction in patients with atrial fibrillation for whom vitamin K antagonist therapy is unsuitable. The recent ARISTOTLE trial found apixaban to be superior to warfarin for stroke prevention in a wide range of patients with atrial fibrillation, with significantly lower bleeding risk, and lower risk of all-cause mortality.
Rogge, C; Hilbert, S; Dagres, N; Hindricks, G
Atrial fibrillation is the most common form of persistent cardiac arrhythmia with a greatly increasing prevalence due to an aging population and increasing cardiovascular risk factors. Apart from impairment of the quality of life atrial fibrillation is associated with a high morbidity, most importantly stroke and heart failure. The therapy is complex and aims at improving symptoms as well as the prevention of thromboembolic complications, heart failure and aggravating comorbidities. Based on individual patient characteristics and symptoms therapy is mainly based on heart rate control by pharmacological means or therapy for maintaining sinus rhythm. This treatment includes antiarrhythmic drugs and catheter ablation. Current research is aimed at the investigation of the electrophysiological mechanisms of recurrent therapy refractive atrial fibrillation and the question whether the maintenance of sinus rhythm can improve the prognosis of atrial fibrillation.
da Silva, Rose Mary Ferreira Lisboa
Inflammation markers have been associated with cardiovascular diseases including atrial fibrillation. This arrhythmia is the most frequent, with an incidence of 38/1000 person-years. The aims of this study are to discuss the association between inflammation, atherosclerosis and atrial fibrillation and its clinical implications. Atherosclerosis is a chronic inflammatory disease and inflammation is a triggering factor of atherosclerotic plaque rupture. In addition to coronary artery disease, clinical conditions identified as risk factors for atrial fibrillation (AF) are also associated with the inflammatory state such as obesity, diabetes mellitus, hypertension, heart failure, metabolic syndrome and sedentary lifestyle. Biomarkers of inflammation, oxidative stress, coagulation, and myocardial necrosis have been identified in patients with atrial fibrillation and these traditional risk factors. Some markers of inflammation were identified as predictors of recurrence of this arrhythmia, subsequent myocardial infarction, stroke by embolism, and death. Thus, approaches to manipulate the inflammatory pathways may be therapeutic interventions, benefiting patients with AF and increased inflammatory markers.
The precise mechanisms of clinical effect of antiarrhythmic agents and the ideal "molecular targets" against arrhythmias, in particular atrial fibrillation, are poorly understood. Current antiarrhythmic drug development, particularly for drugs expected to be active against atrial fibrillation, has focused on drugs with multiple ionic mechanisms of action, in particular on those that block multiple potassium channels. Investigation of antiarrhythmic agents is complicated by the diversity of animal-disease models studied, by the potential multiple mechanisms of arrhythmias, and by the incompletely understood relationships between risks and benefits of antiarrhythmic drug therapy. Furthermore, rhythm control strategies in large groups of patients with atrial fibrillation have failed to show substantial clinical benefit. Nevertheless, drugs that block multiple potassium channels and appear to have relatively little organ toxicity, such as tedisamil, may represent an important new avenue in the therapeutic approach to highly symptomatic arrhythmias such as atrial fibrillation.
Da Poian, Giulia; Liu, Chengyu; Bernardini, Riccardo; Rinaldo, Roberto; Clifford, Gari D
Compressive sensing (CS) approaches to electrocardiogram (ECG) analysis provide efficient methods for real time encoding of cardiac activity. In doing so, it is important to assess the downstream effect of the compression on any signal processing and classification algorithms. CS is particularly suitable for low power wearable devices, thanks to its low-complex digital or hardware implementation that directly acquires a compressed version of the signal through random projections. In this work, we evaluate the impact of CS compression on atrial fibrillation (AF) detection accuracy. We compare schemes with data reconstruction based on wavelet and Gaussian models, followed by a P&T-based identification of beat-to-beat (RR) intervals on the MIT-BIH atrial fibrillation database. A state-of-the-art AF detector is applied to the RR time series and the accuracy of the AF detector is then evaluated under different levels of compression. We also consider a new beat detection procedure which operates directly in the compressed domain, avoiding costly signal reconstruction procedures. We demonstrate that for compression ratios up to 30[Formula: see text] the AF detector applied to RR intervals derived from the compressed signal exhibits results comparable to those achieved when employing a standard QRS detector on the raw uncompressed signals, and exhibits only a 2% accuracy drop at a compression ratio of 60%. We also show that the Gaussian-based reconstruction approach is superior in terms of AF detection accuracy, with a negligible drop in performance at a compression ratio ⩽75%, compared to a wavelet approach, which exhibited a significant drop in accuracy at a compression ratio ⩾65%. The results suggest that CS should be considered as a plausible methodology for both efficient real time ECG compression (at moderate compression rates) and for offline analysis (at high compression rates).
Bayturan, Ozgur; Puri, Rishi; Tuzcu, E Murat; Shao, Mingyuan; Wolski, Kathy; Schoenhagen, Paul; Kapadia, Samir; Nissen, Steven E; Sanders, Prashanthan; Nicholls, Stephen J
Background Despite atrial fibrillation representing an established risk factor for stroke, the association between atrial fibrillation and both progression of coronary atherosclerosis and major adverse cardiovascular events is not well characterized. We assessed the serial measures of coronary atheroma burden and cardiovascular outcomes in patients with and without atrial fibrillation. Methods Data were analyzed from nine clinical trials involving 4966 patients with coronary artery disease undergoing serial intravascular ultrasonography at 18-24 month intervals to assess changes in percent atheroma volume (PAV). Using a propensity weighted analysis, and following adjustment for baseline variables, patients with ( n = 190) or without ( n = 4776) atrial fibrillation were compared with regard to coronary plaque volume and major adverse cardiovascular events (death, myocardial infarction, and stroke). Results Atrial fibrillation patients demonstrated lower baseline PAV (36.0 ± 8.9 vs. 38.1 ± 8.9%, p = 0.002) and less PAV progression (-0.07 ± 0.34 vs. + 0.23 ± 0.34%, p = 0.001) compared with the non-atrial fibrillation group. Multivariable analysis revealed atrial fibrillation to independently predict both myocardial infarction [HR, 2.41 (1.74,3.35), p<0.001] 2.41 (1.74, 3.35), p < 0.00) and major adverse cardiovascular events [HR, 2.2, (1.66, 2.92), p<0.001] 2.20 (1.66, 2.92), p < 0.001]. Kaplan-Meier analysis showed that atrial fibrillation compared with non-atrial fibrillation patients had a significantly higher two-year cumulative incidence of overall major adverse cardiovascular events (4.4 vs. 2.0%, log-rank p = 0.02) and myocardial infarction (3.3 vs. 1.5%, log-rank p = 0.05). Conclusions The presence of atrial fibrillation independently associates with a heightened risk of myocardial infarction despite a lower baseline burden and progression rate of coronary atheroma. Further studies are necessary to define
TANAKA-ESPOSITO, CHRISTINE; CHUNG, MINA K.
When considering anticoagulant therapy for patients with atrial fibrillation, one must balance the reduction in risk of thromboembolism that this therapy offers against the risk of bleeding that it poses. The American Heart Association, American College of Cardiology, and Heart Rhythm Society updated their atrial fibrillation guidelines in 2014. This review outlines a rationale for clinical decision-making based on the new guidelines and summarizes the currently approved drugs. PMID:25552627
Onuchina, E L; Solov'ev, O V; Mochalova, O V; Kononov, S K; Onuchin, S G
The aim of the study was to elucidate specific features of chronic recurrent atrial fibrillation (AF) in patients with metabolic syndrome (MS) and disturbed carbohydrate metabolism compared with AF patients without MS. It enrolled 145 patients aged 44-83 years: 117 with abdominal obesity (BMI >30 kg/m2, waist circumference >80 and 94 cm in women and men respectively) including 30 without metabolic disturbances; 35 with impaired glucose tolerance (IGT), 52 with type 2 DM, and 28 controls without MS. Parameters measured included frequency and severity of AF, carbohydrate and lipid metabolism, albuminurea, C-reactive peptide level, quality of AH control, results of echocardiography and 24 hour ECG monitoring (sinus rhythm), and insulin resistance index (HOMA IRindex). Groups of AF and MS patients were dominated by women. The frequency and severity of AF relapses in MS patients were higher than in controls (especially in the presence of IGT and DM). IGT and DM2 associated with structural changes in myocardium (left atrial dilatation, prevalence of LV concentric hypertrophy, diastolic dysfunction) coupled to higher systolic AH and marked metabolic disorders (hyperglycemia, IR, elevated microalbuminurea and C-reactive protein level, dyslipidemia). These conditions contribute to the frequency and severity of AF relapses. Development of AF in MS is a multifactor problem necessitating strict control of AH, dyslipidemia, DM2 and IGT, reduction of body weight and abdominal obesity.
Dhoble, Abhijeet; Patel, Mehul B; Abdelmoneim, Sahar S; Puttarajappa, Chethan; Abela, George S; Bhatt, Deepak L; Thakur, Ranjan K
Porphyrias are a group of inherited disorders affecting enzymes in the heme biosynthesis pathway, leading to overproduction and/or accumulation of porphyrin or its precursors. Porphyrias have been associated with autonomic dysfunction, which in turn can develop atrial fibrillation (AF). The purpose of this study was to characterize the prevalence of AF and atrial flutter (AFl) in patients with porphyrias. A single-center retrospective cohort study was designed using data from chart reviews of patients who were admitted to the hospital from January 2000 to June 2008. Fifty-six distinct cases were found with a discharge diagnosis of porphyria including all its subtypes. From the same database, age- and gender-matched controls were identified using computer-generated random numbers. We selected 1 age- and gender-matched control for each case. Electrocardiograms and echocardiograms were reviewed by 2 independent reviewers. Only patients with available 12-lead electrocardiograms that showed AF/AFl were labeled with that diagnosis. All patients with a diagnosis of porphyria were included in the study irrespective of their age. Seven of 56 patients with porphyria met inclusion criteria, yielding a prevalence of AF/AFl of 12.5%. This association was significant (p = 0.028, relative risk 7.45, 95% confidence interval 1.01 to 66.14) compared with the age- and gender-matched control group (2%). In conclusion, our observations suggest that porphyria may be significantly associated with AF/AFl.
Roten, Laurent; Derval, Nicolas; Pascale, Patrizio; Scherr, Daniel; Komatsu, Yuki; Shah, Ashok; Ramoul, Khaled; Denis, Arnaud; Sacher, Frédéric; Hocini, Mélèze; Haïssaguerre, Michel; Jaïs, Pierre
Atrial fibrillation (AF) ablation has evolved to the treatment of choice for patients with drug-resistant and symptomatic AF. Pulmonary vein isolation at the ostial or antral level usually is sufficient for treatment of true paroxysmal AF. For persistent AF ablation, drivers and perpetuators outside of the pulmonary veins are responsible for AF maintenance and have to be targeted to achieve satisfying arrhythmia-free success rate. Both complex fractionated atrial electrogram (CFAE) ablation and linear ablation are added to pulmonary vein isolation for persistent AF ablation. Nevertheless, ablation failure and necessity of repeat ablations are still frequent, especially after persistent AF ablation. Pulmonary vein reconduction is the main reason for arrhythmia recurrence after paroxysmal and to a lesser extent after persistent AF ablation. Failure of persistent AF ablation mostly is a consequence of inadequate trigger ablation, substrate modification or incompletely ablated or reconducting linear lesions. In this review we will discuss these points responsible for AF recurrence after ablation and review current possibilities on how to overcome these limitations. PMID:22920482
German, David M; Kabir, Muammar M; Dewland, Thomas A; Henrikson, Charles A; Tereshchenko, Larisa G
Atrial fibrillation (AF) is the most common arrhythmia in adults and is associated with significant morbidity and mortality. Substantial interest has developed in the primary prevention of AF, and thus the identification of individuals at risk for developing AF. The electrocardiogram (ECG) provides a wealth of information, which is of value in predicting incident AF. The PR interval and P wave indices (including P wave duration, P wave terminal force, P wave axis, and other measures of P wave morphology) are discussed with regard to their ability to predict and characterize AF risk in the general population. The predictive value of the QT interval, ECG criteria for left ventricular hypertrophy, and findings of atrial and ventricular ectopy are also discussed. Efforts are underway to develop models that predict AF incidence in the general population; however, at present, little information from the ECG is included in these models. The ECG provides a great deal of information on AF risk and has the potential to contribute substantially to AF risk estimation, but more research is needed.
Chen, Xiaodong; Chen, Minglong; Wang, Yingying; Yang, Bing; Ju, Weizhu; Zhang, Fengxiang; Cao, Kejiang
Abstract We sought to investigate variation of atrial electromechanical interval after catheter ablation procedure in patients with persistent atrial fibrillation using pulse Doppler (PW) and pulse tissue Doppler imaging (PW-TDI). A total of 25 consecutive in-patients with persistent atrial fibrillation, who restored sinus rhythm after ablation procedure, were recruited in our cardiac center. Echocardiography was performed on each patient at 2 hours, 1 day, 5 days, 1 month and 3 months after the ablation therapy, and atrial electromechanical delay was measured simultaneously by PW and PW-TDI. There was no significant difference between PW and TDI in measuring atrial electromechanical delay. However, at postoperative 2 hours, peak A detection rates were mathematically but nonsignificantly greater by PW-TDI than by PW. Second, there was a significant decreasing trend in atrial electromechanical interval from postoperative 2 hours to 3 months, but only postoperative 2-hour atrial electromechanical interval was significantly greater than atrial electromechanical interval at other time. Lastly, patients without postoperative 2-hour atrial electromechanical interval had a significantly longer duration of atrial fibrillation as compared to those with postoperative 2-hour atrial electromechanical interval, by the PW or by PW-TDI, respectively. In patients with persistent atrial fibrillation, atrial electromechanical interval may decrease significantly within the first 24 hours after ablation but remain consistent later, and was significantly related to patients’ duration of atrial fibrillation. Atrial electromechanical interval, as a potential predicted factor, is recommended to be measured by either PW or TDI after 24 hours, when patients had recovered sinus rhythm by radiofrequency ablation. PMID:27924066
Staerk, Laila; Sherer, Jason A; Ko, Darae; Benjamin, Emelia J; Helm, Robert H
The past 3 decades have been characterized by an exponential growth in knowledge and advances in the clinical treatment of atrial fibrillation (AF). It is now known that AF genesis requires a vulnerable atrial substrate and that the formation and composition of this substrate may vary depending on comorbid conditions, genetics, sex, and other factors. Population-based studies have identified numerous factors that modify the atrial substrate and increase AF susceptibility. To date, genetic studies have reported 17 independent signals for AF at 14 genomic regions. Studies have established that advanced age, male sex, and European ancestry are prominent AF risk factors. Other modifiable risk factors include sedentary lifestyle, smoking, obesity, diabetes mellitus, obstructive sleep apnea, and elevated blood pressure predispose to AF, and each factor has been shown to induce structural and electric remodeling of the atria. Both heart failure and myocardial infarction increase risk of AF and vice versa creating a feed-forward loop that increases mortality. Other cardiovascular outcomes attributed to AF, including stroke and thromboembolism, are well established, and epidemiology studies have championed therapeutics that mitigate these adverse outcomes. However, the role of anticoagulation for preventing dementia attributed to AF is less established. Our review is a comprehensive examination of the epidemiological data associating unmodifiable and modifiable risk factors for AF and of the pathophysiological evidence supporting the mechanistic link between each risk factor and AF genesis. Our review also critically examines the epidemiological data on clinical outcomes attributed to AF and summarizes current evidence linking each outcome with AF. © 2017 American Heart Association, Inc.
Pellman, Jason; Sheikh, Farah
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
Kalifa, J; Maixent, JM; Chalvidan, T; Dalmasso, C; Colin, D; Cozma, D; Laurent, P; Deharo, JC; Djiane, P; Cozzone, P; Bernard, M
Background and methods Perturbations in energetic metabolism and impaired atrial contractility may play an important role in the pathogenesis of atrial fibrillation (AF). Besides, atrial stretch is commonly associated with AF. However, the atrial energetics of stretch-related AF are poorly understood. Here, we measured indicators of energy metabolism during acute-stretch related AF. PCr, adenine nucleotides and derivatives concentrations as well as the activity of the F0F1-ATPase and Na,K-ATPase were obtained after one hour of stretch and/or AF in isolated rabbit hearts and compared to control hearts without stretch and AF. Results After one hour of stretch-related AF, the total adenine nucleotides pool was significantly lower (42.2±2.6 versus 63.7±8.3 µmol/g protein in control group, p<0.05) and the PCr/ATP ratio significantly higher (2.3±0.3 vs 1.1± 0.1 in control group p<0.05), because of ATP, ADP and AMP decrease and PCr increase. The sum of high energy phosphate compounds did not change. There were no significant differences in F0F1-ATPase nor Na,K-ATPase activity between the groups. Conclusions Results show that in this experimental model, acute-stretch related AF induces specific modifications of atrial myocytes energetics that may play a pivotal role in the perpetuation of the arrhythmia. PMID:18553177
detection of patients prone to atrial fibrillation (AF), one of the most frequent arrhythmias. It focuses first on the segmentation of the...Keywords : atrial fibrillation , ECG segmentation, P-wave, hidden Markov model, wavelets, ECG database I. INTRODUCTION Atrial fibrillation (AF) is a very... atrial thrombosis, with the subsequent risk of a stroke. The aim of this study is to try to automatically detect patients prone to atrial fibrillation (AF
Rabah, Ali; Wazni, Oussama
Atrial fibrillation and heart failure commonly coexist in the same patient. Each may adversely affect the other. Atrial fibrillation leads to heart failure exacerbation, left ventricular function deterioration and an increase in thrombo-embolic risk. Therapeutic options targeting atrial fibrillation in heart failure patients include pharmacological and non-pharmacological means. Pharmacological therapy is directed at either rate control using nodal blocking agents or rhythm control using anti-arrhythmic agents, of which the options are limited in patients with heart failure. The landmark AF-CHF trial did not show any benefit of rhythm control strategy as opposed to rate control in patients with heart failure and atrial fibrillation. However, patients in this trial as well as in others used mostly amiodarone for rhythm control. This might have negated any positive effects of achieving normal sinus rhythm. Non-pharmacological therapy both for rate and rhythm control is appealing. This includes AV node ablation for rate control, catheter ablation of atrial fibrillation and surgical therapy of atrial fibrillation. This review will address non-pharmacologic treatment of AF in heart failure patients.
Khawar, Waqaar; Smith, Nathan; Masroor, Saqib
Patients with atrial fibrillation are at increased risk for thromboembolic stroke originating predominantly in the left atrial appendage. To reduce the risk, the standard of care is anticoagulation. In addition, several devices for exclusion of the left atrial appendage have been developed. PubMed was searched for articles relevant to left atrial appendage management. The resulting articles were reviewed as were relevant articles in their bibliographies. Relevant journals were manually searched for sources. Devices are being used for left atrial appendage exclusion by percutaneous and surgical approaches. Their indications, limitations, and outcomes are reviewed. Excision and exclusion of the left atrial appendage is safe and as effective as medical management of atrial fibrillation for stroke prevention. The choice of treatment should be made based on patients' anatomy, history, and preference informed by an appropriate left atrial appendage management team. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
Mathew, Joseph P; Fontes, Manuel L; Tudor, Iulia C; Ramsay, James; Duke, Peter; Mazer, C David; Barash, Paul G; Hsu, Ping H; Mangano, Dennis T
Atrial fibrillation is a common, but potentially preventable, complication following coronary artery bypass graft (CABG) surgery. To assess the nature and consequences of atrial fibrillation after CABG surgery and to develop a comprehensive risk index that can better identify patients at risk for atrial fibrillation. Prospective observational study of 4657 patients undergoing CABG surgery between November 1996 and June 2000 at 70 centers located within 17 countries, selected using a systematic sampling technique. From a derivation cohort of 3093 patients, associations between predictor variables and postoperative atrial fibrillation were identified to develop a risk model, which was assessed in a validation cohort of 1564 patients. New-onset atrial fibrillation after CABG surgery. A total of 1503 patients (32.3%) developed atrial fibrillation after CABG surgery. Postoperative atrial fibrillation was associated with subsequent greater resource use as well as with cognitive changes, renal dysfunction, and infection. Among patients in the derivation cohort, risk factors associated with atrial fibrillation were advanced age (odds ratio [OR] for 10-year increase, 1.75; 95% confidence interval [CI], 1.59-1.93); history of atrial fibrillation (OR, 2.11; 95% CI, 1.57-2.85) or chronic obstructive pulmonary disease (OR, 1.43; 95% CI, 1.09-1.87); valve surgery (OR, 1.74; 95% CI, 1.31-2.32); and postoperative withdrawal of a beta-blocker (OR, 1.91; 95% CI, 1.52-2.40) or an angiotensin-converting enzyme (ACE) inhibitor (OR 1.69; 95% CI, 1.38-2.08). Conversely, reduced risk was associated with postoperative administration of beta-blockers (OR, 0.32; 95% CI, 0.22-0.46), ACE inhibitors (OR, 0.62; 95% CI, 0.48-0.79), potassium supplementation (OR, 0.53; 95% CI, 0.42-0.68), and nonsteroidal anti-inflammatory drugs (OR, 0.49; 95% CI, 0.40-0.60). The resulting multivariable risk index had adequate discriminative power with an area under the receiver operating characteristic (ROC
Lau, Chu-Pak; Gbadebo, T David; Connolly, Stuart J; Van Gelder, Isabelle C; Capucci, Alessandro; Gold, Michael R; Israel, Carsten W; Morillo, Carlos A; Siu, Chung-Wah; Abe, Haruhiko; Carlson, Mark; Tse, Hung-Fat; Hohnloser, Stefan H; Healey, Jeff S
Atrial fibrillation (AF) is suggested to be less common among black and Asian individuals, which could reflect bias in symptom reporting and access to care. In the Asymptomatic AF and Stroke Evaluation in Pacemaker Patients and the AF Reduction Atrial Pacing Trial (ASSERT), patients with hypertension but no history of AF had AF recorded via an implanted pacemaker or defibrillator, thus allowing both symptomatic and asymptomatic AF incidence to be determined without ascertainment bias. The ASSERT enrolled 2,580 patients in 23 countries in North America, Europe, and Asia. AF was defined as device-recorded AF episodes >190/min, lasting either for >6 minutes or >6 hours in duration. All ethnic groups with >50 patients were enrolled. Ethnic groups studied include Europeans (n = 1900), black Africans (n = 73), Chinese (n = 89), and Japanese (n = 105) patients. Compared to Europeans, black Africans had more risk factors for AF such as heart failure (27.8 vs 14.6%) and diabetes (41.7 vs 26.3%). At 2.5 years follow-up, all 3 non-European races had a lower incidence of AF (8.3%, 10.1%, and 9.5% vs 18.0%, respectively, for AF>6 minutes, P < 0.006). When adjusted for baseline difference, Chinese had a lower incidence of AF > 6 minutes (P < 0.007), and Japanese and black Africans had a lower incidence of AF > 6 hours (P < 0.04 and P = 0.057, respectively). Black Africans, Chinese, and Japanese had lower incidence of AF compared to Europeans. In the case of black Africans, this is despite an increased prevalence of AF risk factors. © 2013 Wiley Periodicals, Inc.
Afdala, Adfal; Nuryani, Nuryani; Satriyo Nugroho, Anto
Atrial Fibrillation is one of heart disease, that common characterized by irregularity heart beat. Atrial fibrillation leads to severe complications such as cardiac failure with the subsequent risk of a stroke. A method to detect atrial fibrillation is needed to prevent a risk of atrial fibrillation. This research uses data from physionet in atrial fibrillation database category. The performance of Shannon entropy has the highest accuracy if a threshold is 0.5 with accuracy 89.79%, sensitivity 91.04% and specificity 89.01%. Based on the result we get a conclusion, the ability of Shannon entropy to detect atrial fibrillation is good.
Aparina, O P; Chikhireva, L N; Stukalova, O V; Mironova, N A; Kashtanova, S Iu; Ternovoĭ, S K; Golitsyn, S P
Changes of atrial structure and function are the contributors of atrial fibrillation clinical course, complications and treatment effectiveness. Effects of inflammation and mechanical stretch on atrial structural remodeling leading to atrial fibrillation are reviewed in the article. Contemporary invasive and non-invasive methods of evaluation (including late gadolinium enhancement magnetic resonance imaging) of patients with atrial structural remodeling in atrial fibrillation are also described.
Nair, Ajith G; Fischer, Avi G
Hypertrophic cardiomyopathy (HCM) is associated with an increased incidence of supraventricular and ventricular arrhythmias. Atrial fibrillation (AF) is the most common arrhythmia in HCM with a prevalence of 20% and an annual incidence of two percent per year. Increased left atrial size and volume along with impaired left atrial function confer an increased likelihood of AF. The onset of AF is often accompanied by a decrease in functional status in conjunction with an increased risk of stroke and overall mortality.
Olsson, Karen M; Nickel, Nils P; Tongers, Jörn; Hoeper, Marius M
Atrial flutter and fibrillation are being increasingly reported in patients with pulmonary hypertension but little is known about their clinical implications. We sought to determine the incidence and clinical impact of these arrhythmias in patients with pulmonary hypertension. In a 5-year, prospective study, we assessed the incidence of new-onset atrial flutter and fibrillation as well as risk factors, clinical consequences, management, and impact on survival in patients with pulmonary arterial hypertension (PAH, n=157) or inoperable chronic thromboembolic pulmonary hypertension (CTEPH, n=82). The cumulative 5-year incidence of new-onset atrial flutter and fibrillation was 25.1% (95% confidence interval, 13.8-35.4%). The development of these arrhythmias was frequently accompanied by clinical worsening (80%) and signs of right heart failure (30%). Stable sinus rhythm was successfully re-established in 21/24 (88%) of patients initially presenting with atrial flutter and in 16/24 (67%) of patients initially presenting with atrial fibrillation. New-onset atrial flutter and fibrillation were an independent risk factor of death (p=0.04, simple Cox regression analysis) with a higher mortality in patients with persistent atrial fibrillation when compared to patients in whom sinus rhythm was restored (estimated survival at 1, 2 and 3 years 64%, 55%, and 27% versus 97%, 80%, and 57%, respectively; p=0.01, log rank analysis). Atrial flutter and fibrillation develop in a sizable number of patients with PAH or inoperable CTEPH and often lead to clinical deterioration and right heart failure. Mortality is high when sinus rhythm cannot be restored. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.
Sundqvist, Martin; Sandström, Herbert; Sahlin, Carin; Rohani, Morteza; Al-Khalili, Faris; Hörnsten, Rolf; Blomberg, Anders; Wester, Per; Rosenqvist, Mårten; Franklin, Karl A.
Study objectives Obstructive sleep apnea is common among patients with atrial fibrillation, but the prevalence and risk factors for atrial fibrillation among patients who are being investigated on suspicion of sleep apnea are not well known. The aim of the study was to estimate the prevalence of atrial fibrillation among patients investigated for suspected obstructive sleep apnea and to identify risk factors for atrial fibrillation among them. Methods The prevalence of atrial fibrillation was investigated among 201 patients referred for suspected obstructive sleep apnea. Patients without known atrial fibrillation were investigated with a standard 12-lead ECG at hospital and short intermittent handheld ECG recordings at home, during 14 days. Results Atrial fibrillation occurred in 13 of 201 subjects (6.5%), and in 12 of 61 men aged 60 years and older (20%). The prevalence of atrial fibrillation increased with sleep apnea severity (p = 0.038). All patients with atrial fibrillation were men and all had sleep apnea. Age 60 or older, the occurrence of central sleep apnea and diabetes mellitus were independent risk factors for atrial fibrillation after adjustments for body mass index, gender, sleep apnea and cardiovascular disease. Conclusions Atrial fibrillation is common among subjects referred for sleep apnea investigation and the prevalence of atrial fibrillation increases with sleep apnea severity. Independent risk factors for atrial fibrillation among patients investigated for suspected obstructive sleep apnea include the occurrence of coexisting central sleep apnea, age 60 years or older and diabetes mellitus. PMID:28178304
Stewart, G A; Fulton, L J; McKellar, C D
Atrial fibrillation is described in a champion pacer which earlier had been named Australian Harness Horse of the Year as a 3-year-old in 1986-87. Prior to conversion atrial fibrillation had been present for at least 6 weeks, during which the horse had not raced. Successful treatment was achieved with two 10g doses of quinidine sulphate per oesophageal tube, after slow digitalisation with intravenous digoxin over 4d. Four hours after commencement of quinidine therapy the arrhythmia had regressed to atrial flutter and converted to sinus rhythm 10 min later. Considering his age, standard of racing and high reputation the horse's overall performance as a 5-year-old after conversion from atrial fibrillation appeared comparable to his previous performance as a 4-year-old before the disorder occurred. In one of the wins since his return to sinus rhythm, the horse recorded his fastest winning speed and created a new track record at the major Melbourne racetrack. The absence of abnormalities of atrial and atrio-ventricular conduction after the cessation of the arrhythmia, together with the horse's return to successful racing, indicate that this was case of atrial fibrillation occurring as a functional disorder without persistent atrial pathology.
Harris, K; Edwards, D; Mant, J
Atrial fibrillation (AF) is an arrhythmia of increasing prevalence associated with a reducible risk of stroke. We conducted a systematic review to address five questions relating to how we can best detect AF: 1. Are there useful screening tests to determine who should have a 12-lead electrocardiogram (ECG)? Potential screening tests, all with acceptable sensitivity, include pulse palpation, single-lead ECG and newer technologies such as modified sphygmomanometers or a finger probe device. Pulse palpation has a high number of false positives, but is the cheapest method. 2. Is it more effective to offer 12-lead ECGs to the whole population (or specific sub-groups) or only to those who screen positive for AF? The cost-effectiveness of new devices, such as a modified blood pressure monitor, needs to be assessed. It is more cost-effective to opportunistically screen people rather than to offer a 12-lead ECG to everybody. 3. How accurate are different healthcare professionals and interpretative software at diagnosing AF on ECG? Definitive diagnosis of AF should be by 12-lead ECG, interpreted by someone with appropriate expertise. Computer software is not currently sensitive enough to be used alone to diagnose AF on ECG. Primary care practitioners may not accurately detect AF on ECG, but consistently high accuracy can be achieved by healthcare professionals with adequate training. 4. How best can we diagnose paroxysmal atrial fibrillation (PAF)? In patients in whom PAF is suspected, longer periods of monitoring will detect more cases of PAF. 5. What is the impact of the use of different ECG monitoring strategies (e.g. Holter monitoring, serial ECGs, continuous ECG) on AF detection rates post-stroke? In patients post-stroke, a single ECG will miss cases of PAF which can be detected by longer duration monitoring such as Holter monitoring, cardiac event recorders and serial ECGs. Further research into the cost-effectiveness of these methods, the duration of monitoring
Prystowsky, E N
Atrial fibrillation (AF) is the most common sustained arrhythmia in humans. The 3 basic tenets of therapy are (1) restoration and maintenance of sinus rhythm; (2) ventricular rate control; and (3) prevention of thromboembolism. Maintenance of sinus rhythm appears preferable to rate control alone in patients with significant symptoms caused by AF. Complete suppression of AF with drug therapy for >6 months is unusual, but it is not the sole criterion of success. As with other chronic cardiac disorders such as angina and heart failure, a marked reduction in frequency and duration of episodes of AF will likely translate into an excellent clinical outcome. The major risk of antiarrhythmic drug therapy is ventricular proarrhythmia, which is seen most frequently in patients with substantial left ventricular dysfunction. Torsade de pointes is the most frequent proarrhythmia that occurs with antiarrhythmic agents that prolong ventricular repolarization and the QT interval. To minimize the risk of proarrhythmia, antiarrhythmic drugs are started in-hospital in patients with significant heart disease, and agents are selected based on certain patient characteristics. For example, the drugs initially selected for patients with heart failure and coronary artery disease are amiodarone and sotalol, respectively. Two approaches may be used to decrease the thromboembolic risk associated with cardioversion of AF to sinus rhythm. In the conventional method, warfarin is given (INR 2.0-3.0) for 3 weeks before and at least 4 weeks after cardioversion. An alternative approach employs transesophageal echocardiography to rule out left atrial thrombi before cardioversion. Both methods appear reasonable and safe, and I prefer the conventional and transesophageal echocardiography-guided approaches for outpatients and in-hospital patients, respectively.
Dalal, Rahul S.; Sabe, Ashraf A.; Elmadhun, Nassrene Y.; Ramlawi, Basel; Sellke, Frank W.
OBJECTIVE Atrial fibrillation and neurocognitive decline are common complications after cardiopulmonary bypass. By utilizing genomic microarrays we investigate whether gene expression is associated with postoperative atrial fibrillation and neurocognitive decline. METHODS Twenty one cardiac surgery patients were prospectively matched and underwent neurocognitive assessments pre-operatively and four days postoperatively. The whole blood collected in the pre-cardiopulmonary bypass, 6 hours after-cardiopulmonary bypass, and on the 4th postoperative day was hybridized to Affymetrix Gene Chip U133 Plus 2.0 Microarrays. Gene expression in patients who developed postoperative atrial fibrillation and neurocognitive decline (n=6; POAF+NCD) was compared with gene expression in patients with postoperative atrial fibrillation and normal cognitive function (n=5; POAF+NORM) and patients with sinus rhythm and normal cognitive function (n=10; SR+NORM). Regulated genes were identified using JMP Genomics 4.0 with a false discovery rate of 0.05 and fold change of >1.5 or <-1.5. RESULTS Eleven patients developed postoperative atrial fibrillation. Six of these also developed neurocognitive decline. Of the 12 patients with sinus rhythm, only 2 developed neurocognitive decline. POAF+NCD patients had unique regulation of 17 named genes preoperatively, 60 named genes six hours after cardiopulmonary bypass, and 34 named genes four days postoperatively (P<0.05) compared with normal patients. Pathway analysis demonstrated that these genes are involved in cell death, inflammation, cardiac remodeling and nervous system function. CONCLUSION Patients who developed postoperative atrial fibrillation and neurocognitive decline after cardiopulmonary bypass may have differential genomic responses compared to normal patients and patients with only postoperative atrial fibrillation, suggesting common pathophysiology for these conditions. Further exploration of these genes may provide insight into the
Tarride, Jean-Eric; Dolovich, Lisa; Blackhouse, Gordon; Guertin, Jason Robert; Burke, Natasha; Manja, Veena; Grinvalds, Alex; Lim, Ting; Healey, Jeff S; Sandhu, Roopinder K
Screening for undiagnosed atrial fibrillation may lead to treatment with oral anticoagulation therapy, which can decrease the risk of ischemic stroke. The objective of this study was to conduct an economic evaluation of the Program for the Identification of 'Actionable' Atrial Fibrillation in the Pharmacy Setting (PIAAF-Pharmacy), which screened 1145 participants aged 65 years or more at 30 community pharmacies in Ontario and Alberta between October 2014 and April 2015. We used a 2-part decision model to evaluate the short- and long-term costs and quality-adjusted life-years (QALYs) of a pharmacy screening program for atrial fibrillation compared to no screening. Data from the PIAAF-Pharmacy study were used for the short-term model, and the relevant literature was used to extrapolate the benefits of the PIAAF-Pharmacy study in the long-term model. Costs and QALYs were calculated from a payer perspective over a lifetime horizon and were discounted at 1.5%/year. Screening for atrial fibrillation in pharmacies was associated with higher costs ($26) and more QALYs (0.0035) compared to no screening, yielding an incremental cost per QALY gained of $7480. Univariate and probabilistic sensitivity analyses confirmed that screening for atrial fibrillation in a pharmacy setting was a cost-effective strategy. Our results support screening for atrial fibrillation in Canadian pharmacies. Given this finding, efforts should be made by provincial governments and pharmacies to implement such programs in Canada. The addition of atrial fibrillation screening alongside screening and management of other cardiovascular conditions may help to reduce the burden of stroke. Copyright 2017, Joule Inc. or its licensors.
Laukkanen, Jari A; Zaccardi, Francesco; Karppi, Jouni; Ronkainen, Kimmo; Kurl, Sudhir
There is limited knowledge on the relationship between kidney function and incidence of atrial fibrillation. Thus, this prospective study was designed to evaluate whether various biomarkers of kidney function are associated to the risk of atrial fibrillation. The study population consisted of 1840 subjects (615 women and 1225 men) aged 61-82 years. Cystatin C- and creatinine-based estimation of glomerular filtration rate (eGFRcys and eGRFcreat , respectively) and urinary albumin/creatinine ratio (ACR) were assessed to investigate their relationship with the risk of atrial fibrillation. During a median follow-up of 3.7 years, a total of 159 incident atrial fibrillation cases occurred. After adjustment for potential confounders, the risk of atrial fibrillation was increased (hazard ratio 2.74, 95% confidence interval (CI) 1.56-4.81, P < 0.001) in subjects with reduced kidney function (eGFRcys , 15-59 mL/min per 1.73 m(2) ) compared to subjects with normal kidney function (≥90 mL/min per 1.73 m(2) ). Similar results were also found when comparing the respective groups of subjects defined by their eGRFcreat levels (hazard ratio 2.41, CI 1.09-5.30, P = 0.029). Consistently, subjects with ACR ≥300 mg/g had an increased risk of incident atrial fibrillation (hazard ratio 2.16, CI 1.35-2.82, P < 0.001) compared to those with ACR <30 mg/g. Reduced eGFR and albuminuria were associated with an increased risk of atrial fibrillation.
Bayar, Nermin; Üreyen, Çağın Mustafa; Erkal, Zehra; Küçükseymen, Selçuk; Çay, Serkan; Çağırcı, Göksel; Arslan, Şakir
This study aimed to evaluate the association between the history of stroke/transient ischemic attack (TIA) and inter- and intra-atrial electromechanical delay (EMD) in patients with paroxysmal atrial fibrillation (PAF). Patients diagnosed with PAF were included in this retrospective study. Patients who had a history of stroke or TIA were defined as the symptomatic group, whereas those who did not have such a history were defined as the asymptomatic group. On the basis of the transthoracic echocardiographic records, atrial electromechanical coupling (time interval from the onset of the P wave on the surface electrocardiogram to the beginning of the A' wave interval with tissue Doppler echocardiography) and intra- and interatrial EMD were measured. In this study, 160 patients were included, 52 of whom were symptomatic. While the intra-left atrial EMD was 68.2±6.1 ms in the symptomatic group, it was found to be 50.8±6.5 ms in the asymptomatic group (p<0.001). Interatrial EMD was 91.3±5.0 ms in the symptomatic group, whereas it was 71.5±7.0 ms in the asymptomatic group (p<0.001). In multiple logistic regression analysis, intra-left atrial [odds ratio (OR): 1.417, 95% confidence interval (CI): 1.193-1.684, p<0.001] and interatrial EMDs (OR: 1.398, 95% CI: 1.177-1.661, p<0.001) were found to be independently associated with the presence of stroke/TIA. Prolonged inter- and intra-left atrial EMDs in patients with PAF is associated with stroke/TIA. Evaluating this parameter in addition to the CHA2DS2-VASc score in patients with PAF may be helpful in identifying patients who are at a high risk of stroke/TIA.
Gillinov, A Marc; Gelijns, Annetine C; Parides, Michael K; DeRose, Joseph J; Moskowitz, Alan J; Voisine, Pierre; Ailawadi, Gorav; Bouchard, Denis; Smith, Peter K; Mack, Michael J; Acker, Michael A; Mullen, John C; Rose, Eric A; Chang, Helena L; Puskas, John D; Couderc, Jean-Philippe; Gardner, Timothy J; Varghese, Robin; Horvath, Keith A; Bolling, Steven F; Michler, Robert E; Geller, Nancy L; Ascheim, Deborah D; Miller, Marissa A; Bagiella, Emilia; Moquete, Ellen G; Williams, Paula; Taddei-Peters, Wendy C; O'Gara, Patrick T; Blackstone, Eugene H; Argenziano, Michael
Among patients undergoing mitral-valve surgery, 30 to 50% present with atrial fibrillation, which is associated with reduced survival and increased risk of stroke. Surgical ablation of atrial fibrillation has been widely adopted, but evidence regarding its safety and effectiveness is limited. We randomly assigned 260 patients with persistent or long-standing persistent atrial fibrillation who required mitral-valve surgery to undergo either surgical ablation (ablation group) or no ablation (control group) during the mitral-valve operation. Patients in the ablation group underwent further randomization to pulmonary-vein isolation or a biatrial maze procedure. All patients underwent closure of the left atrial appendage. The primary end point was freedom from atrial fibrillation at both 6 months and 12 months (as assessed by means of 3-day Holter monitoring). More patients in the ablation group than in the control group were free from atrial fibrillation at both 6 and 12 months (63.2% vs. 29.4%, P<0.001). There was no significant difference in the rate of freedom from atrial fibrillation between patients who underwent pulmonary-vein isolation and those who underwent the biatrial maze procedure (61.0% and 66.0%, respectively; P=0.60). One-year mortality was 6.8% in the ablation group and 8.7% in the control group (hazard ratio with ablation, 0.76; 95% confidence interval, 0.32 to 1.84; P=0.55). Ablation was associated with more implantations of a permanent pacemaker than was no ablation (21.5 vs. 8.1 per 100 patient-years, P=0.01). There were no significant between-group differences in major cardiac or cerebrovascular adverse events, overall serious adverse events, or hospital readmissions. The addition of atrial fibrillation ablation to mitral-valve surgery significantly increased the rate of freedom from atrial fibrillation at 1 year among patients with persistent or long-standing persistent atrial fibrillation, but the risk of implantation of a permanent pacemaker
Gillinov, A. Marc; Gelijns, Annetine C.; Parides, Michael K.; DeRose, Joseph J.; Moskowitz, Alan J.; Voisine, Pierre; Ailawadi, Gorav; Bouchard, Denis; Smith, Peter K.; Mack, Michael J.; Acker, Michael A.; Mullen, John C.; Rose, Eric A.; Chang, Helena L.; Puskas, John D.; Couderc, Jean-Philippe; Gardner, Timothy J.; Varghese, Robin; Horvath, Keith A.; Bolling, Steven F.; Michler, Robert E.; Geller, Nancy L.; Ascheim, Deborah D.; Miller, Marissa A.; Bagiella, Emilia; Moquete, Ellen G.; Williams, Paula; Taddei-Peters, Wendy C.; O’Gara, Patrick T.; Blackstone, Eugene H.; Argenziano, Michael
Background Among patients undergoing mitral-valve surgery, 30 to 50% present with atrial fibrillation, which is associated with reduced survival and increased risk of stroke. Surgical ablation of atrial fibrillation has been widely adopted, but evidence regarding its safety and effectiveness is limited. Methods We randomly assigned 260 patients with persistent or long-standing persistent atrial fibrillation who required mitral-valve surgery to undergo either surgical ablation (ablation group) or no ablation (control group) during the mitral-valve operation. Patients in the ablation group underwent further randomization to pulmonary-vein isolation or a biatrial maze procedure. All patients underwent closure of the left atrial appendage. The primary end point was freedom from atrial fibrillation at both 6 months and 12 months (as assessed by means of 3-day Holter monitoring). Results More patients in the ablation group than in the control group were free from atrial fibrillation at both 6 and 12 months (63.2% vs. 29.4%, P<0.001). There was no significant difference in the rate of freedom from atrial fibrillation between patients who underwent pulmonary-vein isolation and those who underwent the biatrial maze procedure (61.0% and 66.0%, respectively; P = 0.60). One-year mortality was 6.8% in the ablation group and 8.7% in the control group (hazard ratio with ablation, 0.76; 95% confidence interval, 0.32 to 1.84; P = 0.55). Ablation was associated with more implantations of a permanent pacemaker than was no ablation (21.5 vs. 8.1 per 100 patient-years, P = 0.01). There were no significant between-group differences in major cardiac or cerebrovascular adverse events, overall serious adverse events, or hospital readmissions. Conclusions The addition of atrial fibrillation ablation to mitral-valve surgery significantly increased the rate of freedom from atrial fibrillation at 1 year among patients with persistent or long-standing persistent atrial fibrillation, but the
Xie, Ruiqin; Yang, Yingtao; Cui, Wei; Yin, Hongning; Zheng, Hongmei; Zhang, Jidong; You, Ling
The objective of this study was to study the functional changes of the left atrium after radiofrequency ablation treatment for atrial fibrillation and the therapeutic effect of atorvastatin. Fifty-eight patients undergoing radiofrequency ablation for atrial fibrillation were randomly divided into non-atorvastatin group and atorvastatin group. Patients in the atorvastatin group were treated with atorvastatin 20 mg p.o. per night in addition to the conventional treatment of atrial fibrillation; patients in the non-atorvastatin group received conventional treatment of atrial fibrillation only. Echocardiography was performed before radiofrequency ablation operation and 1 week, 2 weeks, 3 weeks, and 4 weeks after operation. Two-dimensional ultrasound speckle tracking imaging system was used to measure the structural indexes of the left atrium. Results indicated that there was no significant change for indexes representing the structural status of the left atrium within a month after radiofrequency ablation (P > 0.05); however, there were significant changes for indexes representing the functional status of the left atrium. There were also significant changes in indexes reflecting left atrial strain status: the S and SRs of atorvastatin group were higher than those of non-atorvastatin group (P < 0.05). In summary, atorvastatin could improve left atrial function and shorten the duration of atrial stunning after radiofrequency ablation of atrial fibrillation.
von Bodman, G; Brömsen, J; Kopf, C; Füller, M; Block, M
Two young patients with documented episodes of symptomatic paroxysmal atrial fibrillation have been referred for pulmonary vein isolation. Both patients had a history of concomitant regular tachycardia. in both cases pulmonaryvein isolation has not been performed but in each patient a supraventricular tachycardia (right focal atrial tachycardia/atrioventricular reentry tachycardia) could be induced and ablated instead. Concomitant supraventricular tachycardia acting as a trigger arrhythmia is frequent in young patients with atrial fibrillation without underlying cardiacdisease. In these patients a concomitant supra-ventricular tachycardia should beexcluded by electrophysiological study or ablated before pulmonary vein isolation or initiating an antiarrhythmic drug therapy. In most cases ablation of supraventricular tachycardia is safe and successful whereas the risks of ablative therapy of atrial fibrillation can not be neglected and success is moderate.
McCarthy, P M; Castle, L W; Trohman, R G; Simmons, T W; Maloney, J D; Klein, A L; White, R D; Cox, J L
Although atrial fibrillation is well tolerated by most patients, in some patients the consequences may be severe. The Maze procedure is a new open-heart operation that creates a carefully designed maze of incisions in the atrial myocardium; this maze then acts as an electrical conduit to channel atrial impulses from the sinoatrial node to the atrioventricular node. The Maze procedure has been shown to restore sinus rhythm and atrial systole (thus reducing the risk of thromboembolism), improve hemodynamics, alleviate palpitations, and eliminate the need for antiarrhythmic and anticoagulant drugs. We describe our first patient to undergo this operation.
Veltkamp, R; Hacke, W
Atrial fibrillation (AF) causes at least 20% of all ischemic strokes. In large randomized trials of primary and secondary stroke prevention, anticoagulation with vitamin K antagonists (VKA) protected much more efficiently than antiplatelet agents against stroke. Because of the problematic pharmacological properties of VKA only part of the AF patients are currently being treated with oral anticoagulants (OAK). The targeted development of specific oral inhibitors of the central coagulation factors thrombin and factor Xa allows reliable anticoagulation without regular coagulation monitoring. In the present review, pharmacological properties of the different agents are compared. Of the four large randomized phase 3 studies in AF (RELY, ROCKET-AF, ARISTOTLE, ENGAGE-AF) with the primary efficacy endpoint stroke and systemic embolism, the published data from the RELY trial indicate a superior efficacy of dabigatran etexilate (2 × 150 mg/day) and a lower risk of intracranial hemorrhage compared to warfarin. Favorable preliminary results have been demonstrated for the factor Xa inhibitor rivaroxaban. Apixaban was more efficacious than ASA and had a similar risk of hemorrhage in the AVERROES study. Thus, the available data suggest a favorable benefit-risk ratio for the new substances in addition to improved patient comfort. Currently unresolved issues relate to the verification of patient adherence by suitable coagulation tests and to the emergency coagulation diagnostics and therapy in acute ischemic or hemorrhagic strokes under the new OAC.
Xu, Joshua; Luc, Jessica G Y; Phan, Kevin
Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia in modern clinical practice, with an estimated prevalence of 1.5-2%. The prevalence of AF is expected to double in the next decades, progressing with age and increasingly becoming a global medical challenge. The first-line treatment for AF is often medical treatment with either rate control or anti-arrhythmic agents for rhythm control, in addition to anti-coagulants such as warfarin for stroke prevention in patient at risk. Catheter ablation has emerged as an alternative for AF treatment, which involves myocardial tissue lesions to disrupt the underlying triggers and substrates for AF. Surgical approaches have also been developed for treatment of AF, particularly for patients requiring concomitant cardiac surgery or those refractory to medical and catheter ablation treatments. Since the introduction of the Cox-Maze III, this procedure has evolved into several modern variations, including the use of alternative energy sources (Cox-Maze IV) such as radiofrequency, cryo-energy and microwave, as well as minimally invasive thoracoscopic epicardial approaches. Another recently introduced technique is the hybrid ablation approach, where in a single setting both epicardial thoracoscopic ablation lesions and endocardial catheter ablation lesions are performed by the cardiothoracic surgeon and cardiologist. There remains controversy surrounding the optimal approach for AF ablation, energy sources, and lesion sets employed. The goal of this article is review the history, classifications, pathophysiology and current treatment options for AF.
Piccini, Jonathan P.; Mi, Xiaojuan; DeWald, Tracy A.; Go, Alan S.; Hernandez, Adrian F.; Curtis, Lesley H.
Background There are limited data regarding national patterns of pharmacotherapy for atrial fibrillation (AF) among older patients. Drug exposure data are now captured for Medicare beneficiaries enrolled in prescription drug plans. Objective To describe pharmacotherapy for AF among Medicare beneficiaries. Methods Using a 5% national sample of Medicare claims data, we compared demographic characteristics, comorbidity, and treatment patterns according to Medicare Part D status among patients with prevalent AF in 2006 and 2007. Results In 2006, 27,174 patients (29.3%) with prevalent AF were enrolled in Medicare Part D. In 2007, enrollment increased to 45,711 (49.1%). Most enrollees were taking rate control agents (74.0% in 2007). β-Blocker use was higher in those with concomitant AF and heart failure and increased with higher CHADS2 scores (P < .001). Antiarrhythmic use was 18.7% in 2006 and 19.1% in 2007, with amiodarone accounting for more than 50%. Class Ic drugs were used in 3.2% of patients in 2007. Warfarin use was less than 60% and declined with increasing stroke risk (P < .001). Conclusion Pharmacotherapy for AF varied according to comorbidity and underlying risk. Amiodarone was the most commonly prescribed antiarrhythmic agent. Postmarketing surveillance using Medicare Part D claims data linked to clinical data may help inform comparative safety, effectiveness, and net clinical benefit of drug therapy for AF in older patients in real-world settings. PMID:22537885
Alonso, Alvaro; Norby, Faye L.
Atrial fibrillation (AF) is a common cardiac arrhythmia associated with an increased risk of stroke and other complications. Identifying individuals at higher risk of developing AF in the community is now possible using validated predictive models that take into account clinical variables and circulating biomarkers. These models have shown adequate performance in racially and ethnically diverse populations. Similarly, risk stratification schemes predict incidence of ischemic stroke in persons with AF, assisting clinicians and patients in decisions regarding oral anticoagulation use. Complementary schemes have been developed to predict the risk of bleeding in AF patients taking vitamin K antagonists. However, major gaps in our ability to predict AF and its complications exist. Additional research should refine models for AF prediction and determine their value to improve population health and clinical outcomes, advance our ability to predict stroke and other complications in AF patients, and develop predictive models for bleeding events and other adverse effects in patients using non-vitamin K oral anticoagulants. PMID:27008924
Metzner, Andreas; Wissner, Erik; Lin, Tina; Ouyang, Feifan; Kuck, Karl-Heinz
Ablation of atrial fibrillation (AF) is an established treatment option for symptomatic patients refractory to antiarrhythmic medication. In patients with paroxysmal AF, ablation can be offered as first-line therapy when performed in an experienced centre. The accepted cornerstone for all ablation strategies is isolation of the pulmonary veins. However, it is still challenging to achieve contiguous, transmural, permanent lesions using radio-frequency current (RFC) based catheters in conjunction with a three-dimensional mapping system and the learning curve remains long. These limitations have kindled interest in developing and evaluating novel catheter designs that incorporate alternative energy sources. Novel catheters include balloon-based ablation systems, incorporating different energy modalities such as laser (Heartlight(™), CardioFocus, Marlborough, MA, US), RFC (Hot Balloon Catheter, Hayama Arrhythmia Institute, Kanagawa, Japan) and cryo-energy (ArcticFront, Medtronic, Inc., Minneapolis, MN, US). While the cryoballoon (CB) and the radiofrequency hot balloon (RHB) are single-shot devices, the endoscopic ablation system (EAS) allows for point-by-point ablation. The CB and EAS are well established as safe, time-efficient and effective ablation tools. Initial studies using the RHB could also demonstrate promising results. However, more data are required.
Xu, Joshua; Luc, Jessica G. Y.
Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia in modern clinical practice, with an estimated prevalence of 1.5–2%. The prevalence of AF is expected to double in the next decades, progressing with age and increasingly becoming a global medical challenge. The first-line treatment for AF is often medical treatment with either rate control or anti-arrhythmic agents for rhythm control, in addition to anti-coagulants such as warfarin for stroke prevention in patient at risk. Catheter ablation has emerged as an alternative for AF treatment, which involves myocardial tissue lesions to disrupt the underlying triggers and substrates for AF. Surgical approaches have also been developed for treatment of AF, particularly for patients requiring concomitant cardiac surgery or those refractory to medical and catheter ablation treatments. Since the introduction of the Cox-Maze III, this procedure has evolved into several modern variations, including the use of alternative energy sources (Cox-Maze IV) such as radiofrequency, cryo-energy and microwave, as well as minimally invasive thoracoscopic epicardial approaches. Another recently introduced technique is the hybrid ablation approach, where in a single setting both epicardial thoracoscopic ablation lesions and endocardial catheter ablation lesions are performed by the cardiothoracic surgeon and cardiologist. There remains controversy surrounding the optimal approach for AF ablation, energy sources, and lesion sets employed. The goal of this article is review the history, classifications, pathophysiology and current treatment options for AF. PMID:27747025
Hijazi, Ziad; Oldgren, Jonas; Siegbahn, Agneta; Granger, Christopher B; Wallentin, Lars
Assessment of atrial fibrillation (AF)-associated stroke risk is at present mainly based on clinical risk scores such as CHADS2 and CHA2DS2-VASc, although these scores provide only modest discrimination of risk for individual patients. Biomarkers derived from the blood may help refine risk assessment in AF for stroke outcomes and for mortality. Recent studies of biomarkers in AF have shown that they can substantially improve risk stratification. Cardiac biomarkers, such as troponin and natriuretic peptides, significantly improve risk stratification in addition to current clinical risk stratification models. Similar findings have recently been described for markers of renal function, coagulation, and inflammation in AF populations based on large randomized prospective clinical trials or large community-based cohorts. These new findings may enable development of novel tools to improve clinical risk assessment in AF. Biomarkers in AF may also improve the understanding of the pathophysiology of AF further as well as potentially elucidate novel treatment targets. This review will highlight novel associations of biomarkers and outcomes in AF as well as recent progress in the use of biomarkers for risk stratification.
Saengklub, Nakkawee; Limprasutr, Vudhiporn; Sawangkoon, Suwanakiet; Hamlin, Robert L.; Kijtawornrat, Anusak
Atrial fibrillation (AF) is a supraventricular arrhythmia that leads to a decrease in cardiac output and impairs cardiac function and quality of life. Dronedarone has an atrial-selective property and has been used for management of AF in humans, but limited information is available in dogs. This study was designed to evaluate efficacy of dronedarone in attenuating the duration of AF in dog model of sustained AF. Six beagle dogs were anesthetized with isoflurane and instrumented to measure atrial action potential duration (aAPD) and atrial effective refractory period (AERP). Then AF was induced by rapid right atrial pacing (20 V, 40 Hz) simultaneously with infusion of phenylephrine (2 µg/kg/min, intravenously) for 20 min. The duration of sustained AF was recorded, and the animals were allowed to recover. Dronedarone was given at a dose of 20 mg/kg, BID, orally for 7 days. On the last day, the dogs were anesthetized again to record aAPD and AERP, and AF was induced with the same procedure as described above. The results showed that after dronedarone administration the aAPD was lengthened significantly from 76.4 ± 4.2 ms to 91.2 ± 3.9 ms (P<0.05) and AERP was prolonged significantly from 97.5 ± 2.8 ms to 120 ± 4.8 ms (P<0.05). The duration of sustained AF was also significantly attenuated after receipt of dronedarone (P<0.05). It can be suggested that oral dronedarone attenuates the duration of sustained AF in a dog model of AF by extending the AERP more than the aAPD, causing post-repolarization refractoriness. Hence, dronedarone may be useful for management of AF in dogs. PMID:28381818
Starek, Zdenk; Lehar, Frantisek; Jez, Jiri; Wolf, Jiri; Novák, Miroslav
Atrial fibrillation is the most common sustained arrhythmia. Because of the sub-optimal outcomes and associated risks of medical therapy as well as the recent advances in non-pharmacologic strategies, a multitude of combined (hybrid) algorithms have been introduced that improve efficacy of standalone therapies while maintaining a high safety profile. Antiarrhythmic administration enhances success rate of electrical cardioversion. Catheter ablation of antiarrhythmic drug-induced typical atrial flutter may prevent recurrent atrial fibrillation. Through simple ablation in the right atrium, suppression of atrial fibrillation may be achieved in patients with previously ineffective antiarrhythmic therapy. Efficacy of complex catheter ablation in the left atrium is improved with antiarrhythmic drugs. Catheter ablation followed by permanent pacemaker implantation is an effective and safe treatment option for selected patients. Additional strategies include pacing therapies such as atrial pacing with permanent pacemakers, preventive pacing algorithms, and/or implantable dual-chamber defibrillators are available. Modern hybrid strategies combining both epicardial and endocardial approaches in order to create a complex set of radiofrequency lesions in the left atrium have demonstrated a high rate of success and warrant further research. Hybrid therapy for atrial fibrillation reviews history of development of non-pharmacological treatment strategies and outlines avenues of ongoing research in this field.
Stárek, Zdeněk; Lehar, František; Jež, Jiří; Wolf, Jiří; Novák, Miroslav
Atrial fibrillation is the most common sustained arrhythmia. Because of the sub-optimal outcomes and associated risks of medical therapy as well as the recent advances in non-pharmacologic strategies, a multitude of combined (hybrid) algorithms have been introduced that improve efficacy of standalone therapies while maintaining a high safety profile. Antiarrhythmic administration enhances success rate of electrical cardioversion. Catheter ablation of antiarrhythmic drug-induced typical atrial flutter may prevent recurrent atrial fibrillation. Through simple ablation in the right atrium, suppression of atrial fibrillation may be achieved in patients with previously ineffective antiarrhythmic therapy. Efficacy of complex catheter ablation in the left atrium is improved with antiarrhythmic drugs. Catheter ablation followed by permanent pacemaker implantation is an effective and safe treatment option for selected patients. Additional strategies include pacing therapies such as atrial pacing with permanent pacemakers, preventive pacing algorithms, and/or implantable dual-chamber defibrillators are available. Modern hybrid strategies combining both epicardial and endocardial approaches in order to create a complex set of radiofrequency lesions in the left atrium have demonstrated a high rate of success and warrant further research. Hybrid therapy for atrial fibrillation reviews history of development of non-pharmacological treatment strategies and outlines avenues of ongoing research in this field. PMID:25028165
Bloomfield, Gerald S.; Temu, Tecla; Akwanalo, Constantine O.; Chen, Peng-Sheng; Emonyi, Wilfred; Heckbert, Susan R.; Koech, Myra M.; Manji, Imran; Shen, Changyu; Vatta, Matteo; Velazquez, Eric J.; Wessel, Jennifer; Kimaiyo, Sylvester; Inui, Thomas S.
Background There is an urgent need to understand genetic associations with atrial fibrillation in ethnically diverse populations. There are no such data from sub-Saharan Africa, despite the fact that atrial fibrillation is one of the fastest-growing diseases. Moreover, patients with valvular heart disease are under-represented in studies of the genetics of atrial fibrillation. Methods We designed a case-control study of patients with and without a history of atrial fibrillation in Kenya. Cases with atrial fibrillation included those with and without valvular heart disease. Patients underwent clinical phenotyping and will have laboratory analysis and genetic testing of >240 candidate genes associated with cardiovascular diseases. A 12-month follow-up assessment will determine the groups’ morbidity and mortality. The primary analyses will describe genetic and phenotypic associations with atrial fibrillation. Results We recruited 298 participants: 72 (24%) with non-valvular atrial fibrillation, 78 (26%) with valvular atrial fibrillation and 148 (50%) controls without atrial fibrillation. The mean age of cases and controls were 53 and 48 years, respectively. Most (69%) participants were female. Controls more often had hypertension (45%) than those with valvular atrial fibrillation (27%). Diabetes and current tobacco smoking were uncommon. A history of stroke was present in 25% of cases and in 5% of controls. Conclusion This is the first study determining genetic associations in valvular and non-valvular atrial fibrillation in sub-Saharan Africa with a control population. The results advance knowledge about atrial fibrillation and will enhance international efforts to decrease atrial fibrillation-related morbidity. PMID:26385028
Bloomfield, Gerald S; Temu, Tecla M; Akwanalo, Constantine O; Chen, Peng-Sheng; Emonyi, Wilfred; Heckbert, Susan R; Koech, Myra M; Manji, Imran; Shen, Changyu; Vatta, Matteo; Velazquez, Eric J; Wessel, Jennifer; Kimaiyo, Sylvester; Inui, Thomas S
There is an urgent need to understand genetic associations with atrial fibrillation in ethnically diverse populations. There are no such data from sub-Saharan Africa, despite the fact that atrial fibrillation is one of the fastest growing diseases. Moreover, patients with valvular heart disease are underrepresented in studies of the genetics of atrial fibrillation. We designed a case-control study of patients with and without a history of atrial fibrillation in Kenya. Cases with atrial fibrillation included those with and without valvular heart disease. Patients underwent clinical phenotyping and will have laboratory analysis and genetic testing of >240 candidate genes associated with cardiovascular diseases. A 12-month follow-up assessment will determine the groups' morbidity and mortality. The primary analyses will describe genetic and phenotypic associations with atrial fibrillation. We recruited 298 participants: 72 (24%) with nonvalvular atrial fibrillation, 78 (26%) with valvular atrial fibrillation, and 148 (50%) controls without atrial fibrillation. The mean age of cases and controls were 53 and 48 years, respectively. Most (69%) participants were female. Controls more often had hypertension (45%) than did those with valvular atrial fibrillation (27%). Diabetes and current tobacco smoking were uncommon. A history of stroke was present in 25% of cases and in 5% of controls. This is the first study determining genetic associations in valvular and nonvalvular atrial fibrillation in sub-Saharan Africa with a control population. The results advance knowledge about atrial fibrillation and will enhance international efforts to decrease atrial fibrillation-related morbidity. Copyright © 2015 Elsevier Inc. All rights reserved.
Montenegro, Márcio José; Quintella, Edgard Freitas; Damonte, Aníbal; Sabino, Hugo de Castro; Zajdenverg, Ricardo; Laufer, Gustavo Pinaud; Amorim, Bernardo; Estrada, André Pereira Duque; Armas, Cristian Paul Yugcha; Sterque, Aline
Atrial fibrillation is associated with embolic strokes that often result in death or disability. Effective in reducing these events, anticoagulation has several limitations and has been widely underutilized. Over 90% of thrombi identified in patients with atrial fibrillation without valvular disease originate in the left atrial appendage, whose occlusion is investigated as an alternative to anticoagulation. To determine the feasibility of percutaneous occlusion of the left atrial appendage in patients at high risk of embolic events and limitations to the use of anticoagulation. We report our initial experience with Amplatzer Cardiac Plug™ (St. Jude Medical Inc., Saint Paul, Estados Unidos) in patients with nonvalvular atrial fibrillation. We selected patients at high risk of thromboembolism, major bleeding, contraindications to the use or major instability in response to the anticoagulant. The procedures were performed percutaneously under general anesthesia and transesophageal echocardiography. The primary outcome was the presence of periprocedural complications and follow-up program included clinical and echocardiographic review within 30 days and by telephone contact after nine months. In five selected patients it was possible to occlude the left atrial appendage without periprocedural complications. There were no clinical events in follow-up. Controlled clinical trials are needed before percutaneous closure of the left atrial appendage should be considered an alternative to anticoagulation in nonvalvular atrial fibrillation. But the device has shown to be promissory in patients at high risk of embolism and restrictions on the use of anticoagulants.
Camm, A John; Corbucci, Giorgio; Padeletti, Luigi
The problem of early recognition of atrial fibrillation (AF) is greatly aggravated by the often silent nature of the rhythm disturbance. In about 1/3 of patients with this arrhythmia, patients are not aware of the so-called asymptomatic AF. In the past 15 years, the diagnostic data provided by implanted pacemakers and defibrillators have dramatically increased knowledge about silent AF. The unreliability of symptoms to estimate AF burden and to identify patients with and without AF has been pointed out not only by pacemaker trials but also in patients without implanted devices. The technology for continuous monitoring of AF has been largely validated. It is a powerful tool to detect silent paroxysmal AF in patients without previously documented arrhythmic episodes, such as those with cryptogenic stroke or other risk factors. Early diagnosis triggers earlier treatment for primary or secondary stroke prevention. Today, new devices are also available for pure electrocardiographic monitoring, implanted subcutaneously using a minimally invasive technique. In conclusion, this recent and promising technology adds relevant clinical and scientific information to improve risk stratification for stroke and may play an important role in testing and tailoring the therapies for rhythm and rate control.
Shamoun, Fadi; Obeid, Hiba; Ramakrishna, Harish
Atrial fibrillation continues to be a significant source of morbidity and mortality worldwide. Effective anticoagulation remains the cornerstone of outpatient and inpatient treatment. The use of the new generation of anticoagulants (NOACs) continues to grow. Recently published data indicate their cost-effectiveness and overall safety in stroke prevention; compared to vitamin K antagonists, they can be prescribed in fixed doses for long-term therapy without the need for coagulation monitoring. Both United States and European Guidelines recommend NOACs for stroke prevention in patients with atrial fibrillation. This review discusses each of the NOACs, along with their efficacy and safety data. It explores the most recent guidelines regarding their perioperative use in atrial fibrillation patients. It also discusses bleeding complications, perioperative management, and reversal agents. PMID:26221593
Kaiser, Stefanie; Kirst, Malte; Kunze, Christophe
Two versions of a new detector for automatic real-time detection of atrial fibrillation in non-invasive ECG signals are introduced. The methods are based on beat to beat variability, tachogram analysis and simple signal filtering. The implementation on mobile devices is made possible due to the low demand on computing power of the employed analysis procedures. The proposed algorithms correctly identified 436 of 440 five minute episodes of atrial fibrillation or flutter and also correctly identified up to 302 of 342 episodes of no atrial fibrillation, including normal sinus rhythm as well as other cardiac arrhythmias. These numbers correspond to a sensitivity of 99.1 % and a specificity of 88.3%.
Weitz, Jeffrey I; Eikelboom, John
The non-vitamin K antagonist oral anticoagulants (NOACs) are replacing warfarin for stroke prevention in many patients with nonvalvular atrial fibrillation. Edoxaban, an oral factor Xa inhibitor, is the newest entrant in this class. Results of the Effective Anticoagulation with Factor Xa Next Generation in Atrial Fibrillation (ENGAGE AF) study demonstrate that edoxaban is noninferior to warfarin for prevention of stroke and systemic embolic events, and is associated with significantly less major bleeding, including intracranial bleeding, and reduced cardiovascular mortality. With a net clinical benefit over warfarin, edoxaban is well positioned as a choice among the NOACs, which include dabigatran, rivaroxaban, and apixaban. But how will clinicians choose amongst them? The purpose of this paper is to (a) place the ENGAGE AF trial results into context with results of the studies with the other NOACs, and (b) aid clinicians in selection of the right anticoagulant for the right atrial fibrillation patient.
Gómez-Doblas, Juan José; Muñiz, Javier; Martin, Joaquín J Alonso; Rodríguez-Roca, Gustavo; Lobos, José Maria; Awamleh, Paula; Permanyer-Miralda, Gaietá; Chorro, Francisco Javier; Anguita, Manuel; Roig, Eulalia
Atrial fibrillation is associated with substantial morbidity and mortality and both its incidence and prevalence are high. Nevertheless, comprehensive data on this condition in Spain are lacking. The aim of this study was to estimate the prevalence of atrial fibrillation in Spain. A cross-sectional study was conducted in the general Spanish population older than 40 years. Two-stage random sampling was used, in which first-stage units were primary care physicians randomly selected in every Spanish province and second-stage units were 20 randomly selected persons drawn from each participating physician's assigned population. The reported prevalence was standardized for the age and sex distribution of the Spanish population. The electrocardiogram recordings were read centrally. Overall, 8343 individuals were evaluated. The mean age was 59.2 years (95% confidence interval, 58.6-59.8 years), and 52.4% of the participants were female. The overall age-adjusted prevalence of atrial fibrillation was 4.4% (95% confidence interval, 3.8-5.1). Prevalence was similar in both sexes, men 4.4% (3.6-5.2) and women 4.5% (3.6-5.3), rising with increasing age older than 60 years. In patients older than 80 years, the prevalence was 17.7% (14.1-21.3). In 10% of patients an unknown atrial fibrillation was diagnosed. The prevalence of atrial fibrillation in the general Spanish population older than 40 years is high, at 4.4%. The prevalence is similar in both sexes and rises steeply above 60 years of age. It is estimated that there are over 1 million patients with atrial fibrillation in the Spanish population, of whom over 90,000 are undiagnosed. Copyright © 2013 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.
Conroy, Thomas; Hernandez Guzman, Jairo; Hall, Burr; Tsouri, Gill; Couderc, Jean-Phillippe
Atrial Fibrillation (AF) is the most common cardiac arrhythmia in the world, associated with increased risk of thromboembolic events and an increased mortality rate. In addition, a significant portion of AF patients are asymptomatic. Current AF diagnostic methods, often including a body surface electrocardiogram or implantable loop recorder, are both expensive and invasive and offer limited access within the general community. Objective We tested the feasibility of the detection of AF using photoplethysmographic signal acquired from an inexpensive, non-invasive earlobe photoplethysmographic sensor. This technology can be implemented into wearable devices and would enable continuous cardiac monitoring capabilities, greatly improving the rate of asymptomatic AF detection. Approach We conducted a clinical study of patients going through electrical cardioversion for AF treatment. Photoplethysmographic recordings were taken from these AF patients before and after their cardioversion procedure, along with recordings from a healthy control group. Using these recordings, cardiac beats were identified and the inter-systolic interval was calculated. The inter-systolic interval was used to calculate four parameters to quantify the heart rate variability indicative of AF. Receiver Operating Characteristic curves were used to calculate discriminant thresholds between the AF and Non-AF cohorts. Main Results The parameter with the greatest discriminant capability resulted in a sensitivity and specificity of 90.9%. These results are comparable to expensive ECG-based and invasive implantable loop recorder AF detection methods. Significance These results demonstrate that using non-invasive earlobe photoplethysmographic signal is a viable and inexpensive alternative to ECG-based AF detection methods, and an alternative that could be invaluable in detecting subclinical AF. © 2017 Institute of Physics and Engineering in Medicine.
Karim, R.; Mohiaddin, R.; Rueckert, D.
Segmentation of the left atrium is vital for pre-operative assessment of its anatomy in radio-frequency catheter ablation (RFCA) surgery. RFCA is commonly used for treating atrial fibrillation. In this paper we present an semi-automatic approach for segmenting the left atrium and the pulmonary veins from MR angiography (MRA) data sets. We also present an automatic approach for further subdividing the segmented atrium into the atrium body and the pulmonary veins. The segmentation algorithm is based on the notion that in MRA the atrium becomes connected to surrounding structures via partial volume affected voxels and narrow vessels, the atrium can be separated if these regions are characterized and identified. The blood pool, obtained by subtracting the pre- and post-contrast scans, is first segmented using a region-growing approach. The segmented blood pool is then subdivided into disjoint subdivisions based on its Euclidean distance transform. These subdivisions are then merged automatically starting from a seed point and stopping at points where the atrium leaks into a neighbouring structure. The resulting merged subdivisions produce the segmented atrium. Measuring the size of the pulmonary vein ostium is vital for selecting the optimal Lasso catheter diameter. We present a second technique for automatically identifying the atrium body from segmented left atrium images. The separating surface between the atrium body and the pulmonary veins gives the ostia locations and can play an important role in measuring their diameters. The technique relies on evolving interfaces modelled using level sets. Results have been presented on 20 patient MRA datasets.
Lubitz, Steven A.; Weng, Lu-Chen; Christophersen, Ingrid E.; Boerwinkle, Eric; Gibbs, Richard A.; Cupples, L. Adrienne; Mohler, Peter J.; Nickerson, Deborah A.; Muzny, Donna; Psaty, Bruce M.; Soliman, Elsayed Z.; Sotoodehnia, Nona; Lunetta, Kathryn L.; Heckbert, Susan R.; Arking, Dan E.; Ellinor, Patrick T.
Atrial fibrillation (AF) is a morbid and heritable arrhythmia. Over 35 genes have been reported to underlie AF, most of which were described in small candidate gene association studies. Replication remains lacking for most, and therefore the contribution of coding variation to AF susceptibility remains poorly understood. We examined whole exome sequencing data in a large community-based sample of 1,734 individuals with and 9,423 without AF from the Framingham Heart Study, Cardiovascular Health Study, Atherosclerosis Risk in Communities Study, and NHLBI-GO Exome Sequencing Project and meta-analyzed the results. We also examined whether genetic variation was enriched in suspected AF genes (N = 37) in AF cases versus controls. The mean age ranged from 59 to 73 years; 8,656 (78%) were of European ancestry. None of the 99,404 common variants evaluated was significantly associated after adjusting for multiple testing. Among the most significantly associated variants was a common (allele frequency = 86%) missense variant in SYNPO2L (rs3812629, p.Pro707Leu, [odds ratio 1.27, 95% confidence interval 1.13–1.43, P = 6.6x10-5]) which lies at a known AF susceptibility locus and is in linkage disequilibrium with a top marker from prior analyses at the locus. We did not observe significant associations between rare variants and AF in gene-based tests. Individuals with AF did not display any statistically significant enrichment for common or rare coding variation in previously implicated AF genes. In conclusion, we did not observe associations between coding genetic variants and AF, suggesting that large-effect coding variation is not the predominant mechanism underlying AF. A coding variant in SYNPO2L requires further evaluation to determine whether it is causally related to AF. Efforts to identify biologically meaningful coding variation underlying AF may require large sample sizes or populations enriched for large genetic effects. PMID:27589061
Carter, Lindsey; Gardner, Martin; Magee, Kirk; Fearon, Ann; Morgulis, Inna; Doucette, Steve; Sapp, John L; Gray, Chris; Abdelwahab, Amir; Parkash, Ratika
Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia resulting in mortality and morbidity. Gaps in oral anticoagulation and education of patients regarding AF have been identified as areas that require improvement. A before-and-after study of 433 patients with newly diagnosed AF in the 3 emergency departments in Nova Scotia from January 1, 2011 until January 31, 2014 was performed. The "before" phase underwent the usual-care pathway for AF management; the "after" phase was enrolled in a nurse-run, physician-supervised AF clinic. The primary outcome was a composite of death, cardiovascular hospitalization, and AF-related emergency department visits. A propensity analysis was performed to account for differences in baseline characteristics. A total of 185 patients were enrolled into the usual-care group, and 228 patients were enrolled in the AF clinic group. The mean age was 64±15 years and 44% were women. In a propensity-matched analysis, the primary outcome occurred in 44 (26.2%) patients in the usual-care group and 29 (17.3%) patients in the AF clinic group (odds ratio 0.71; 95% CI [0.59, 1]; P=0.049) at 12 months. Prescription of oral anticoagulation was increased in the CHADS2 ≥2 group (88.4% in the AF clinic versus 58.5% in the usual-care group, P<0.01). Adoption of this integrated management approach for the burgeoning population of AF may provide an overall benefit to cardiovascular morbidity and mortality. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.
Lau, Dennis H; Middeldorp, Melissa E; Brooks, Anthony G; Ganesan, Anand N; Roberts-Thomson, Kurt C; Stiles, Martin K; Leong, Darryl P; Abed, Hany S; Lim, Han S; Wong, Christopher X; Willoughby, Scott R; Young, Glenn D; Kalman, Jonathan M; Abhayaratna, Walter P; Sanders, Prashanthan
Recent community-based research has linked aortic stiffness to the development of atrial fibrillation. We posit that aortic stiffness contributes to adverse atrial remodeling leading to the persistence of atrial fibrillation following catheter ablation in lone atrial fibrillation patients, despite the absence of apparent structural heart disease. Here, we aim to evaluate aortic stiffness in lone atrial fibrillation patients and determine its association with arrhythmia recurrence following radio-frequency catheter ablation. We studied 68 consecutive lone atrial fibrillation patients who underwent catheter ablation procedure for atrial fibrillation and 50 healthy age- and sex-matched community controls. We performed radial artery applanation tonometry to obtain central measures of aortic stiffness: pulse pressure, augmentation pressure and augmentation index. Following ablation, arrhythmia recurrence was monitored at months 3, 6, 9, 12 and 6 monthly thereafter. Compared to healthy controls, lone atrial fibrillation patients had significantly elevated peripheral pulse pressure, central pulse pressure, augmentation pressure and larger left atrial dimensions (all P<0.05). During a mean follow-up of 2.9±1.4 years, 38 of the 68 lone atrial fibrillation patients had atrial fibrillation recurrence after initial catheter ablation procedure. Neither blood pressure nor aortic stiffness indices differed between patients with and without atrial fibrillation recurrence. However, patients with highest levels (≥75(th) percentile) of peripheral pulse pressure, central pulse pressure and augmentation pressure had higher atrial fibrillation recurrence rates (all P<0.05). Only central aortic stiffness indices were associated with lower survival free from atrial fibrillation using Kaplan-Meier analysis. Aortic stiffness is an important risk factor in patients with lone atrial fibrillation and contributes to higher atrial fibrillation recurrence following catheter ablation procedure.
Paventi, S; Parafati, M A; Pellegrino, C A; Bevilacqua, U; Paggi, A
Normal atrial mechanic function may not return immediately after the successful cardioversion of atrial fibrillation. It has been suggested that the delayed recovery of atrial contraction (atrial stunning) might be due to: 1. the energy delivered during direct current cardioversion 2. the time from the onset of atrial fibrillation 3. the left atrial size 4. the associated cardiac disease. This study evaluates "atrial stunning" in patients pharmacologically treated, with atrial fibrillation of recent onset, normal atrial size and without heart disease. Doppler echocardiography is well suited for assessment of atrial function due to the ability of recording the peak velocity of atrial contraction (A wave). Twenty-five patients with no evidence of heart disease and M-mode left atrial dimension less than 40 mm underwent successful pharmacologic cardioversion (pro-paphenon or flecainide 2 mg/kg/10 min) of atrial fibrillation of recent onset (less than 48 hours). After cardioversion an echocardiographic study was performed within 12 hours (ECO 1), on day 3 (ECO 2), on day 12 (ECO 3), and on day 30 (ECO 4). No significant difference of both left atrial size (37 +/- 3.9 mm; 38.22 +/- 3.8 mm; 38.02 +/- 4.7 mm; 38.2 +/- 4.14 mm) and peak E velocity (57.97 +/- 18.3 mm/sec; 59.4 +/- 18.3 mm/sec; 59.0 +/- 16 mm/sec; 59.07 +/- 16.7 mm/sec) was demonstrated among serial echocardiographic evaluations. Both peak A velocity (mm/sec) and E/A ratio were significantly different in ECO 1 (60.29 +/- 12.3-1.0 +/- 0.37) than in ECO 2 (73.1 +/- 10.7, p < 0.005-0.82 +/- 0.27, p < 0.05); no statistical difference was found between ECO 2 and ECO 3 (76.31 +/- 12-0.78 +/- 0.24 mm/sec)--ECO 4 (76.91 +/- 14.8-0.78 +/- 0.21 mm/sec). This study suggests that patients with atrial fibrillation of recent onset have a delayed recovery of normal atrial systolic function after pharmacologic cardioversion.
Rienstra, Michiel; Van Gelder, Isabelle C
In the last few years, there has been a major shift in the treatment of atrial fibrillation (AF) in the setting of hear failure (HF), from rhythm to ventricular rate control in most patients with both conditions. In this article, the authors focus on ventricular rate control and discuss the indications; the optimal ventricular rate-control target, including detailed results of the Rate Control Efficacy in Permanent Atrial Fibrillation: a Comparison Between Lenient versus Strict Rate Control II (RACE II) study; and the pharmacologic and nonpharmacologic options to control the ventricular rate during AF in the setting of HF. Copyright © 2013 Elsevier Inc. All rights reserved.
Wilde, Sandra; Wiltink, Jörg; Wild, Philipp S.; Sinning, Christoph R.; Lubos, Edith; Ojeda, Francisco M.; Zeller, Tanja; Munzel, Thomas; Blankenberg, Stefan; Beutel, Manfred E.
Background Initial evidence suggests that depressive symptoms are more frequent in patients with atrial fibrillation. Data from the general population are limited. Methods and Results In 10,000 individuals (mean age 56±11 years, 49.4% women) of the population-based Gutenberg Health Study we assessed depression by the Patient Health Questionnaire (PHQ-9) and a history of depression in relation to manifest atrial fibrillation (n = 309 cases). The median (25th/75th percentile) PHQ-9 score of depressive symptoms was 4 (2/6) in atrial fibrillation individuals versus 3 (2/6) individuals without atrial fibrillation, . Multivariable regression analyses of the severity of depressive symptoms in relation to atrial fibrillation in cardiovascular risk factor adjusted models revealed a relation of PHQ-9 values and atrial fibrillation (odds ratio (OR) 1.04, 95% confidence interval (CI) 1.01–1.08; P = 0.023). The association was stronger for the somatic symptom dimension of depression (OR 1.08, 95% CI 1.02–1.15; P = 0.0085) than for cognitive symptoms (OR 1.05, 95% CI 0.98–1.11; P = 0.15). Results did not change markedly after additional adjustment for heart failure, partnership status or the inflammatory biomarker C-reactive protein. Both, self-reported physical health status, very good/good versus fair/bad, (OR 0.54, 95% CI 0.41–0.70; P<0.001) and mental health status (OR 0.61 (0.46–0.82); P = 0.0012) were associated with atrial fibrillation in multivariable-adjusted models. Conclusions In a population-based sample we observed a higher burden of depressive symptoms driven by somatic symptom dimensions in individuals with atrial fibrillation. Depression was associated with a worse perception of physical or mental health status. Whether screening and treatment of depressive symptoms modulates disease progression and outcome needs to be shown. PMID:24324579
Gorenek, Bulent; Kudaiberdieva, Gulmira
Atrial fibrillation is the most common arrhythmia associated with increased mortality and morbidity. Its management requires high healthcare expenditures; 52%-70% of expenses for AF care are constituted by hospitalization costs. The current management strategies of pharmacological rhythm control and pharmacological or invasive rate control show no difference in impact on major outcomes in patients with AF. Radiofrequency catheter ablation (RFA) has been shown to reduce the risk of AF recurrence, improve quality of life and reduce hospitalization rate as compared to pharmacological rhythm control and rate control strategies. This review summarizes current knowledge on cost and cost-effectiveness analysis of RFA for patients with atrial fibrillation.
Yadava, Mrinal; Hughey, Andrew B; Crawford, Thomas Christopher
Atrial fibrillation is the most commonly encountered arrhythmia after cardiac surgery. Although usually self-limiting, it represents an important predictor of increased patient morbidity, mortality, and health care costs. Numerous studies have attempted to determine the underlying mechanisms of postoperative atrial fibrillation (POAF) with varied success. A multifactorial pathophysiology is hypothesized, with inflammation and postoperative β-adrenergic activation recognized as important contributing factors. The management of POAF is complicated by a paucity of data relating to the outcomes of different therapeutic interventions in this population. This article reviews the literature on epidemiology, mechanisms, and risk factors of POAF, with a subsequent focus on the therapeutic interventions and guidelines regarding management.
Khabchabov PhD, Rustam; Rg PhD, Khabchabov; Er PhD, Makhmudova
Resume In accordance with modern concepts, one of the leading roles in the development of paroxysmal atrial fibrillation and flutter, belongs - the restructuring of the myocardium, in second place - sick sinus syndrome and in third place - the presence of accessory pathways and hormonal disorders. The development of atrial fibrillation and flutter in the structural pathology, primarily begins with of drugs if it does not work, we have to carry out ablation. Providing proper, effective and important combination therapy - is the main challenge in cardiology.
Cohoon, Kevin P; McBane, Robert D; Ammash, Naser; Slusser, Joshua P; Grill, Diane E; Wysokinski, Waldemar E
Atrial fibrillation and obesity are two major growing epidemics in the United States and globally. Obese people are at the increased risk of developing atrial fibrillation. The contribution of obesity as an independent risk factor for stroke in the setting of atrial fibrillation remains unclear. We tested the hypothesis that non-valvular atrial fibrillation (NVAF) patients with increased body mass index (BMI) would be at increased risk for the development of left atrial appendage thrombus (LAAT). Consecutive, anticoagulation naïve patients with NVAF referred for a transesophageal echocardiogram (TEE) between January 1, 2007 and October 21, 2009 were approached for study participation. All clinical, laboratory, and TEE measurement data were collected prospectively. Within a group of 400 anticoagulation naïve NVAF patients (mean age 63 ± 15 years, 28 % women; 17 % with LAAT) the prevalence of LAAT was similar across all BMI categories (normal 13 %, overweight 19 %, obese 16 %, morbidly obese 16 %; p = 0.71). Despite a higher CHADS2 score and a higher prevalence of both hypertension and diabetes mellitus, elevated BMI was not an independent predictor of LAAT when analyzed as either a continuous variable, across BMI WHO categories, a dichotomous variable stratified at values above versus below 27 kg/m(2), or BMI stratified on atrial fibrillation duration. Despite a higher prevalence of major risk factors for thromboembolism, the prevalence of LAAT was not increased in overweight, obese, and morbidly obese patients.
Pérez-Villacastín, Julián; Pérez Castellano, Nicasio; Moreno Planas, Javier
Atrial fibrillation is the most common sustained arrhythmia. Because of its potentially serious clinical consequences (heart failure, stroke, and cognitive impairment), atrial fibrillation has important socioeconomic and health implications. This article reviews the major studies on the epidemiology of atrial fibrillation in Spain. Recent data suggest that in people older than 40 years, the prevalence of atrial fibrillation may be more than 4%. Given the current Spanish demography, these data would imply that more than 1 million people in Spain have atrial fibrillation.
Nührich, Jana M; Geisler, Anne C; Steven, Daniel; Hoffmann, Boris A; Schäffer, Benjamin; Lund, Gunnar; Stehning, Christian; Radunski, Ulf K; Sultan, Arian; Schwarzl, Michael; Adam, Gerhard; Willems, Stephan; Muellerleile, Kai
Extensive and repeated substrate modification (SM) is frequently performed as an ablation strategy in persistent atrial fibrillation (persAF). The effect of these extended ablation strategies on atrial function has not been investigated sufficiently so far. The purpose was to assess atrial function by cardiac magnetic resonance (CMR) and its association with left atrial (LA) scar burden by electroanatomical voltage-mapping after multiple persAF ablation procedures. We included 16 persAF patients who had ≥2 SM procedures and a control group (CG) of 21 persAF patients without prior ablation. CMR was performed in sinus rhythm at least 4 weeks after the last cardioversion. Active left and right (RA) atrial emptying fractions (AEF) as well as peak active left atrial appendage (LAA) emptying velocities were obtained by CMR flow measurements. Furthermore, LA scar burden was quantified on electroanatomical voltage maps by the portion of points with local voltage amplitude <0.2 mV. We found median LA-AEF to be lower (13 [9-22] vs 32 [26-36] %, P < 0.001) and median LA scar burden to be higher (40 [20-68] vs nine [3-18] %, P < 0.05) in the SM group compared with the CG. Furthermore, a significant correlation was found between mean LA voltage and LA-AEF (r(2) = 0.62, P < 0.001). No significant differences were detected with respect to median RA-AEF (41 [28-48] vs 47 [35-50] %, P = 0.43) and median peak LAA emptying velocities (30 [16-40] vs 17 [13-28] cm/s, P = 0.07). Active LA function is preserved but significantly impaired and associated with ablation-related LA scar burden after multiple extensive persAF ablations. ©2016 Wiley Periodicals, Inc.
Lai, Yau-Huei; Yun, Chun-Ho; Su, Cheng-Huang; Yang, Fei-Shih; Yeh, Hung-I; Hou, Charles Jia-Yin; Wu, Tung-Hsin; Cury, Ricardo C; Bezerra, Hiram G
Abstract Purpose Pericardial adipose tissue had been shown to exert local effects on adjacent cardiac structures. Data regarding the mechanistic link between such measures and left atrial (LA) structural/functional remodeling, a clinical hallmark of early stage heart failure (HF) and atrial fibrillation (AF) incidence, in asymptomatic population remain largely unexplored. Methods This retrospective analysis includes 356 subjects free from significant valvular disorders, atrial fibrillation, or clinical HF. Regional adipose tissue including pericardial and periaortic fat volumes, interatrial septal (IAS), and left atrioventricular groove (AVG) fat thickness were all measured by multidetector computed tomography (MDCT) (Aquarius 3D Workstation, TeraRecon, San Mateo, CA, USA). We measured LA volumes, booster performance, reservoir capacity as well as conduit function, and analyzed their association with adiposity measures. Results All four adiposity measures were positively associated with greater LA volumes (all P < 0.05), while IAS and AVG fat were also related to larger LA kinetic energy and worse reservoir capacity (both P < 0.01). In multivariate models, IAS fat thickness remained independently associated with larger LA volumes, increased LA kinetic energy and ejection force (β-coef: 0.17 & 0.15, both P < 0.05), and impaired LA reservoir and conduit function (β-coef: −0.20 & −0.12, both P < 0.05) after adjusting for clinical variables. Conclusion Accumulated visceral adiposity, especially interatrial fat depots, was associated with certain LA structural/functional remodeling characterized by impaired LA reservoir and conduit function though augmented kinetic energy and ejection performance. Our data suggested that interatrial fat burden may be associated with certain detrimental LA functions with compensatory LA adaptation in an asymptomatic population. PMID:27249809
Barbati, Giovanni; De Domenico, Renato; Rossi, Stefania; Vecchiato, Elena; Zeppellini, Roberto
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.
Wakili, Reza; Voigt, Niels; Kääb, Stefan; Dobrev, Dobromir; Nattel, Stanley
Atrial fibrillation (AF) is an extremely common cardiac rhythm disorder that causes substantial morbidity and contributes to mortality. The mechanisms underlying AF are complex, involving both increased spontaneous ectopic firing of atrial cells and impulse reentry through atrial tissue. Over the past ten years, there has been enormous progress in understanding the underlying molecular pathobiology. This article reviews the basic mechanisms and molecular processes causing AF. We discuss the ways in which cardiac disease states, extracardiac factors, and abnormal genetic control lead to the arrhythmia. We conclude with a discussion of the potential therapeutic implications that might arise from an improved mechanistic understanding. PMID:21804195
Pisani, Paolo; Sandrelli, Luca; Fabbrocini, Mario; Tesler, Ugo Filippo; Medici, Dante
Percutaneous closure of the left atrial appendage (LAA) is a new approach to the prevention of cardioembolic events in patients with atrial fibrillation. We implanted an LAA occlusion device (Amplatzer™ Cardiac Plug) in a 70-year-old woman via a transseptal approach. Upon her discharge from the hospital, a transthoracic echocardiogram showed stable anchoring of the device; 6 months after implantation, a routine transthoracic echocardiogram revealed migration of the occluder into the left ventricular outflow tract, in the absence of symptoms. We surgically removed the device from the mitral subvalvular apparatus and closed the LAA with sutures. This case shows that percutaneous LAA occlusion can result in serious adverse events, including device migration in the absence of signs or symptoms; therefore, careful follow-up monitoring is mandatory.
Sandrelli, Luca; Fabbrocini, Mario; Tesler, Ugo Filippo; Medici, Dante
Percutaneous closure of the left atrial appendage (LAA) is a new approach to the prevention of cardioembolic events in patients with atrial fibrillation. We implanted an LAA occlusion device (Amplatzer™ Cardiac Plug) in a 70-year-old woman via a transseptal approach. Upon her discharge from the hospital, a transthoracic echocardiogram showed stable anchoring of the device; 6 months after implantation, a routine transthoracic echocardiogram revealed migration of the occluder into the left ventricular outflow tract, in the absence of symptoms. We surgically removed the device from the mitral subvalvular apparatus and closed the LAA with sutures. This case shows that percutaneous LAA occlusion can result in serious adverse events, including device migration in the absence of signs or symptoms; therefore, careful follow-up monitoring is mandatory. PMID:25120404
McBane, Robert D; Hodge, David O; Wysokinski, Waldemar E
Although infrequent, embolic occlusion to non-cerebral arteries may result in limb loss, organ failure, and death. The aim of this study was to define clinical and echocardiographic characteristics determining thromboembolism destination in non-valvular atrial fibrillation. An inception cohort of individuals (n=72) were identified with incident peripheral embolism in the setting of non-valvular atrial fibrillation (1995-2005). A randomly selected group of atrial fibrillation related stroke patients (n=100) were identified for comparison. Arteries of the extremities were the most common site of embolism (85%); lower extremity involvement was twice as common compared with the upper extremity. Clinical features distinguishing peripheral embolism from stroke included age>75, heart failure and hypertension. Severe left ventricular dysfunction, spontaneous echo contrast and left atrial thrombus were 2-3 fold more common in peripheral embolism patients. Mean CHADS-2 scores were low and comparable for both groups. By multivariate analysis, age>5 years (hazard ratio [HR] 2.3, 95% confidence interval [CI] 1.3-3.9; p=0.05) was predictive of peripheral embolism. After adjustment for age>75 years, severe left atrial enlargement (HR 1.8, 95% CI 0.99-3.1; p=0.055) and CHADS score (HR 1.2, 95% CI 0.99-1.6; p=0.06) were of borderline significance. In conclusion, several clinical and echocardiographic measures distinguish the clinical presentation of thromboembolism in non-valvular atrial fibrillation. Small emboli are destined to lodge in the cerebral circulation as a result of hydrodynamic, anatomic, and physical factors. Advanced age, atrial enlargement and other co-morbidities may increase the propensity for the formation of larger thrombi which may bypass the carotid orifice merely as a function of size.
Tsutsui, Kenta; Ajiki, Kohsuke; Fujiu, Katsuhito; Imai, Yasushi; Hayami, Noriyuki; Murakawa, Yuji
Atrial tachycardia (AT) and atrial fibrillation (AF) were observed in a 21-year old male who had a history of patch closure for an atrial septal defect (ASD) at the age of 5 and a persistent left superior vena cava (LSVC). During electrophysiologic study, atrial extrastimuli reproducibly induced AT which spontaneously terminated or changed into AF. Electroanatomical mapping revealed focal AT arising from the floor of the proximal LSVC. Radio- frequency applications within LSVC targeted to the earliest activation site of AT as well as the complex fractionated potential eliminated both AT and AF without trans-septal puncture.
Goldberger, Jeffrey J.; Arora, Rishi; Green, David; Greenland, Philip; Lee, Daniel C.; Lloyd-Jones, Donald M.; Markl, Michael; Ng, Jason; Shah, Sanjiv J.
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
McCabe, Pamela J; Rhudy, Lori M; DeVon, Holli A
To describe patients' experiences from symptom onset to initial treatment for atrial fibrillation. The estimated number of individuals with atrial fibrillation globally in 2010 was 33·5 million. World-wide, each year, new cases of atrial fibrillation approach 5 million, and prevalence will increase 2·5-fold by 2050. As a result, clinicians worldwide will treat a growing number of patients with atrial fibrillation. Early intervention to promote atrial fibrillation self-management is critical to reduce associated complications of stroke and heart failure. Greater understanding of patients' experiences from symptom onset to initial treatment for atrial fibrillation is needed to guide development of interventions to promote early effective self-management. A descriptive qualitative design was used. Twenty females and 21 males at an academic medical centre were interviewed using open-ended questions to explore their experiences from symptom onset to initial treatment for atrial fibrillation. Data were analysed using qualitative content analysis. Participants' mean age was 64·3 (SD = 10·1) years. Four themes were identified: (1) misinterpreting symptoms; (2) discovering the meaning of atrial fibrillation; (3) facing fears, uncertainty, and moving to acceptance; and (4) receiving validation and reassurance. Participants lacked knowledge of atrial fibrillation and took cues from providers' responses to appraise symptoms and diagnosis. Fear and uncertainty were reduced when providers initiated prompt treatment and took time to explain atrial fibrillation. Patients appreciated receiving clear information about atrial fibrillation, were engaged in learning, and motivated to participate in their care. Providers played a critical role in helping patients to develop an accurate understanding of atrial fibrillation, to cope with the new diagnosis, and motivated them to engage in effective self-management. Insight into participant experiences from symptom onset to initial
Cengel, Atiye; Sahinarslan, Asife; Biberoğlu, Gursel; Hasanoğlu, Alev; Tavil, Yusuf; Tulmaç, Murat; Ozdemir, Murat
Atrial fibrillation (AF) is known to be related with increased risk of thromboembolic events. Asymmetrical dimethylarginine (ADMA), which is an endogenous inhibitor of nitric oxide synthase (NOS), can cause endothelial dysfunction by decreasing nitric oxide (NO) and lead to increased risk of thrombosis. In the present study our aim was to compare plasma levels of ADMA in patients with acute onset (< 24 hours) and chronic AF (> 1 year) to determine the risk of thrombosis. 17 patients with the first detected attack of AF within the first 24 hours of presentation (group 1), 25 patients who had permanent chronic AF lasting at least 1 year or more (group II) and 18 healthy persons as the control group (group III) were included in the study. For each patient the plasma ADMA, L-arginine, symmetrical dimethylarginine (SDMA) concentrations were measured by high-performance liquid chromatography in venous blood samples collected before cardioversion. We compared the plasma ADMA, L-arginine and SDMA concentrations between the groups. Plasma L-arginine (78.18 +/- 28.29 vs. 73.14 +/- 14.11 vs. 71.03 +/- 21.31, P = 0.549) and plasma SDMA concentrations (0.38 +/-0.18 vs. 0.42 +/- 0.21 vs. 0.32 +/- 0.24, P = 0.224) were similar in all groups. There was a significant difference between plasma ADMA concentrations (0.76 +/- 0.27 vs. 0.50 +/- 0.26 vs. 0.36 +/- 0.20, P < 0.001) among the groups. When we compared plasma ADMA levels between the subgroups, we also found a significant difference (P = 0.002 when comparing group I and group II, P < 0.001 when comparing of group I and group III, P = 0.042 when compareng of group II and group III). ADMA levels in patients with acute onset AF were significantly increased when compared with patients with chronic AF and the healthy control group indicating the presence of endothelial dysfunction and a prothrombotic state even in a very early phase of AF.
Urtubia Palacios, A; Usieto López, L; Fernández Esteban, M I; Puértolas Ortega, M
Torsade de pointes is a frequent cause of sudden death of cardiac origin, with uncertain mechanisms of actions and very diverse origins. A case is presented of a patient with a bronchial condition on pharmacological treatment with macrolides, and who, as well as having atrial fibrillation, suffered an episode of self-limiting torsade de pointes that abated spontaneously with no associated clinical complications.
Calvo Romero, J M
In clinical practice, low-molecular-weight heparins are used relatively frequently in patients with atrial fibrillation to prevent embolic events. In this article, it is revised the available evidence in the following clinical situations: rapid onset of anticoagulation, bridging therapy (replacing long-term oral anticoagulant therapy around an invasive procedure) and transesophageal echocardiography-guided cardioversion.
Brick, Alexandre Visconti; Braile, Domingo Marcolino
Surgical ablation, concomitant with other operations, is an option for treatment in patients with chronic atrial fibrillation. The aim of this study is to present a literature review on surgical ablation of atrial fibrillation in patients undergoing cardiac surgery, considering energy sources and return to sinus rhythm. A comprehensive survey was performed in the literature on surgical ablation of atrial fibrillation considering energy sources, sample size, study type, outcome (early and late), and return to sinus rhythm. Analyzing studies with immediate results (n=5), the percentage of return to sinus rhythm ranged from 73% to 96%, while those with long-term results (n=20) (from 12 months on) ranged from 62% to 97.7%. In both of them, there was subsequent clinical improvement of patients who underwent ablation, regardless of the energy source used. Surgical ablation of atrial fibrillation is essential for the treatment of this arrhythmia. With current technology, it may be minimally invasive, making it mandatory to perform a procedure in an attempt to revert to sinus rhythm in patients requiring heart surgery.
Brick, Alexandre Visconti; Braile, Domingo Marcolino
Surgical ablation, concomitant with other operations, is an option for treatment in patients with chronic atrial fibrillation. The aim of this study is to present a literature review on surgical ablation of atrial fibrillation in patients undergoing cardiac surgery, considering energy sources and return to sinus rhythm. A comprehensive survey was performed in the literature on surgical ablation of atrial fibrillation considering energy sources, sample size, study type, outcome (early and late), and return to sinus rhythm. Analyzing studies with immediate results (n=5), the percentage of return to sinus rhythm ranged from 73% to 96%, while those with long-term results (n=20) (from 12 months on) ranged from 62% to 97.7%. In both of them, there was subsequent clinical improvement of patients who underwent ablation, regardless of the energy source used. Surgical ablation of atrial fibrillation is essential for the treatment of this arrhythmia. With current technology, it may be minimally invasive, making it mandatory to perform a procedure in an attempt to revert to sinus rhythm in patients requiring heart surgery. PMID:26934404
Diener, Hans-Christoph; Weber, Ralph; Lip, Gregory Y H; Hohnloser, Stefan H
Oral anticoagulation with vitamin K antagonists (warfarin, phenprocoumon) is successful in both primary and secondary stroke prevention in patients with atrial fibrillation, yielding a 60-70% relative reduction in stroke risk compared with placebo, as well as a mortality reduction of 26%. However, these agents have a number of well documented shortcomings. Acetylsalicylic acid (ASA) reduces the relative risk of stroke by a nonsignificant 19% compared with placebo, and increased bleeding risk offsets any therapeutic gain from the combination of ASA with clopidogrel. This review describes the current landscape and developments in stroke prevention in patients with atrial fibrillation, with special reference to secondary prevention. A number of new drugs for oral anticoagulation that do not exhibit the limitations of vitamin K antagonists are under investigation. These include direct factor Xa inhibitors and direct thrombin inhibitors. Recent studies (RE-LY, ROCKET-AF, AVERROES, ARISTOTLE) provide promising results for new agents, including higher efficacy and significantly lower incidences of intracranial bleeds compared with warfarin. The new substances show similar results in secondary as in primary stroke prevention in patients with atrial fibrillation. New anticoagulants add to the therapeutic options for patients with atrial fibrillation, and offer a number of advantages over warfarin, for both the clinician and patient, including a favourable bleeding profile and convenience of use. Consideration of these new anticoagulants will improve clinical decision making.
Rawles, J M; Rowland, E
The belief that there is total irregularity of the pulse in atrial fibrillation has been re-examined. In a computerised analysis of R-R intervals and pulse volumes, 100-500 (mean 237) consecutive cycles were examined in 74 patients with atrial fibrillation, of whom 36 were on digoxin and 38 were not taking any antiarrhythmic treatment. A Doppler ultrasound technique was used to assess pulse volumes, against which R-R intervals were correlated. Although the sequence of consecutive R-R intervals was random in 52 (70%), patients there was a significant correlation between consecutive intervals in 22 (30%), the correlation coefficient being negative in 11 and positive in 11. In 43 (58%) cases the sequence of consecutive pulse volumes was significantly non-random; 34 (46%) showed pulsus alternans, indicated by a negative correlation between consecutive volumes. The proportion of patients with a non-random sequence of R-R intervals or pulse volumes was the same whether or not they were taking digoxin. Thus patients with atrial fibrillation often have patterns of regularity of the pulse, with the ventricular rhythm being non-random in almost one third and the sequence of pulse volumes being non-random in over a half. Contrary to classic teaching, in many patients with atrial fibrillation the pulse is not irregularly irregular. PMID:3730206
Rordorf, Roberto; Savastano, Simone; Gandolfi, Edoardo; Vicentini, Alessandro; Petracci, Barbara; Landolina, Maurizio
Catheter ablation has been proven to be an effective treatment for patients with drug-resistant atrial fibrillation. Nevertheless its efficacy is limited to 60-80% of patients in different studies. Whether the use of pharmacological therapy after catheter ablation of atrial fibrillation might increase the procedural success rate is still a matter of debate. There is general agreement that antiarrhythmic drugs (AADs) are useful in the management of arrhythmias occurring in the very early period after catheter ablation (blanking period). On the contrary, limited data are available on the efficacy of AADs over a longer period. Some patients remain free of arrhythmia recurrences by the use of AADs that were ineffective before catheter ablation: whether this latter situation is to be considered a partial success of catheter ablation or a treatment failure, thus demanding a redo procedure, is still an open question. Some studies have also investigated the role of non-AADs [angiotensin-converting enzyme (ACE) inhibitors, angiotensin II receptor blockers, statins and corticosteroids] in preventing atrial fibrillation recurrences after catheter ablation, reporting conflicting results. Whereas there is a general consensus on the use of anticoagulation therapy in the first phase after catheter ablation, no definite data are available on the proper long-term management of anticoagulation therapy after catheter ablation. This review focuses on the still open issue of what is the optimal pharmacological treatment of patients after catheter ablation of atrial fibrillation.
Strecker, Thomas; Agaimy, Abbas; Zelzer, Peter; Weyand, Michael; Wachter, David Lukas
Primary cardiac tumors are very rare, atrial myxoma being the most common benign tumor of the heart. They may present with a great variety of incidental asymptomatic masses to severe life-threatening cardiovascular complications necessitating emergency surgery. Here we report the diagnostic evaluation and successful surgical resection of such a giant cardiac tumor which was found on a routine medical check-up in a 62-year-old patient. Histology confirmed diagnosis of unusually huge myxoma. This article demonstrates it’s necessary to include cardiac tumors in the differential diagnosis of subtle and non-specific cardiothoracic symptoms. PMID:25120848
Donahue, J Kevin
Atrial fibrillation is a prominent cause of morbidity and mortality in developed countries. Treatment strategies center on controlling atrial rhythm or ventricular rate. The need for anticoagulation is an independent decision from the rate versus rhythm control debate. This review discusses novel biological strategies that have potential utility in the management of atrial fibrillation. Rate controlling strategies predominately rely on G-protein gene transfer to enhance cholinergic or suppress adrenergic signaling pathways in the atrioventricular node. Calcium channel blocking gene therapy and fibrosis enhancing cell therapy have also been reported. Rhythm controlling strategies focus on disrupting reentry by enhancing conduction or suppressing repolarization. Efforts to suppress inflammation and apoptosis are also under study. Resistance to blood clot formation has been shown with thrombomodulin. These strategies are in various stages of preclinical development.
Abstract This paper reviews the simulations of catheter ablation in computer models of the atria, from the first attempts to the most recent anatomical models. It describes how postulated substrates of atrial fibrillation can be incorporated into mathematical models, how modelling studies can be designed to test ablation strategies, what their current trade‐offs and limitations are, and what clinically relevant lessons can be learnt from these simulations. Drawing a parallel between clinical and modelling studies, six ablation targets are considered: pulmonary vein isolation, linear ablation, ectopic foci, complex fractionated atrial electrogram, rotors and ganglionated plexi. The examples presented for each ablation target illustrate a major advantage of computer models, the ability to identify why a therapy is successful or not in a given atrial fibrillation substrate. The integration of pathophysiological data to create detailed models of arrhythmogenic substrates is expected to solidify the understanding of ablation mechanisms and to provide theoretical arguments supporting substrate‐specific ablation strategies. PMID:26846178
Kanda, Takashi; Masuda, Masaharu; Sunaga, Akihiro; Fujita, Masashi; Iida, Osamu; Okamoto, Shin; Ishihara, Takayuki; Watanabe, Tetsuya; Takahara, Mitsuyoshi; Sakata, Yasushi; Uematsu, Masaaki
Recurrence after catheter ablation of persistent atrial fibrillation (AF) remains an unsolved issue. This study aimed to explore the association between the left atrial appendage peak flow velocity (LAAV) and AF recurrence after ablation in persistent AF patients. Fifty-three consecutive patients who underwent an initial catheter ablation of persistent AF were enrolled [age, 65±10 years; male, 42 (79%)]. The LAAV was obtained by transesophageal echocardiography before ablation. All the patients underwent pulmonary vein isolation and were followed up for 12 months. The LAAV and other clinical factors (AF duration, CHA2DS2VASc score, left atrial diameter, left atrial volume, and left ventricular ejection fraction) were tested using a Cox proportional hazards regression analysis as predictors of AF recurrence during the 1-year follow-up. AF recurrence occurred in 16 (30%) patients. The patients with AF recurrences had lower LAAVs (23.3±7.2cm/s vs. 33.3±15.1cm/s, p=0.002) than those without AF recurrence. In the multivariable analysis, a low LAAV independently predicted AF recurrence (hazard ratio, 3.04; 95% confidence interval, 1.05-8.79; p=0.040). A Kaplan-Meier analysis also demonstrated a lower survival rate free from AF recurrence in the low LAAV group than in the high LAAV group (p=0.030). A low LAAV was associated with AF recurrence after the initial catheter ablation of persistent AF. Copyright © 2015. Published by Elsevier Ltd.
Cerasuolo, Joshua O.; Cipriano, Lauren E.; Sposato, Luciano A.
Purpose of review Atrial fibrillation is being increasingly diagnosed after ischemic stroke and transient ischemic attack (TIA). Patient characteristics, frequency and duration of paroxysms, and the risk of recurrent ischemic stroke associated with atrial fibrillation detected after stroke and TIA (AFDAS) may differ from atrial fibrillation already known before stroke occurrence. We aim to summarize major recent advances in the field, in the context of prior evidence, and to identify areas of uncertainty to be addressed in future research. Recent findings Half of all atrial fibrillations in ischemic stroke and TIA patients are AFDAS, and most of them are asymptomatic. Over 50% of AFDAS paroxysms last less than 30 s. The rapid initiation of cardiac monitoring and its duration are crucial for its timely and effective detection. AFDAS comprises a heterogeneous mix of atrial fibrillation, possibly including cardiogenic and neurogenic types, and a mix of both. Over 25 single markers and at least 10 scores have been proposed as predictors of AFDAS. However, there are considerable inconsistencies across studies. The role of AFDAS burden and its associated risk of stroke recurrence have not yet been investigated. Summary AFDAS may differ from atrial fibrillation known before stroke in several clinical dimensions, which are important for optimal patient care strategies. Many questions remain unanswered. Neurogenic and cardiogenic AFDAS need to be characterized, as it may be possible to avoid some neurogenic cases by initiating timely preventive treatments. AFDAS burden may differ in ischemic stroke and TIA patients, with distinctive diagnostic and treatment implications. The prognosis of AFDAS and its risk of recurrent stroke are still unknown; therefore, it is uncertain whether AFDAS patients should be treated with oral anticoagulants. PMID:27984303
Troupis, John; Crossett, Marcus; Scneider-Kolsky, Michal; Nandurkar, Dee
Accessory left atrial appendages and atrial diverticula have an incidence of 10-27%. Their association with atrial fibrillation needs to be confirmed. This study determined the prevalence, number, size, location and morphology of accessory left atrial appendages/atrial diverticula in patients with atrial fibrillation compared with those in sinus rhythm. A retrospective analysis of 47 consecutive patients with atrial fibrillation who underwent 320 multidetector Coronary CT angiography (CCTA) was performed. A random group of 47 CCTA patients with sinus rhythm formed the control group. The presence, number, size, location and morphology of accessory left atrial appendages and atrial diverticula in each group were analysed. Twenty one patients had a total of 25 accessory left atrial appendages and atrial diverticula in the atrial fibrillation group and 22 patients had a total of 24 accessory left atrial appendages and atrial diverticula in the sinus rhythm group. Twenty-one atrial diverticula were identified in 19 patients in the atrial fibrillation group and 19 atrial diverticula in 17 patients in the sinus rhythm group. The mean length and width of accessory left atrial appendage was 6.9 and 4.7 mm, respectively in the atrial fibrillation group and 12 and 4.6 mm, respectively, in the sinus rhythm group, P = ns (not significant). The mean length and width of atrial diverticulum was 4.7 and 3.6 mm, respectively in the atrial fibrillation group and 6.2 and 5 mm, respectively in the sinus rhythm group (P = ns). Eighty-four % and 96% of the accessory left atrial appendages/atrial diverticula in the atrial fibrillation and sinus rhythm groups were located along the right anterosuperior left atrial wall. Accessory left atrial appendages and atrial diverticula are common structures with similar prevalence in patients with atrial fibrillation and sinus rhythm.
Mirza, Mahek; Shen, Win-Kuang; Sofi, Aamir; Tran, Canh; Jahangir, Ahad; Sultan, Sulaiman; Khan, Uzma; Viqar, Maria; Cho, Chi; Jahangir, Arshad
Sleep apnea has been recognized as a factor predisposing to atrial fibrillation recurrence and progression. The effect of other sleep-disturbing conditions on atrial fibrillation progression is not known. We sought to determine whether frequent periodic leg movement during sleep is a risk factor for progression of atrial fibrillation. In this retrospective study, patients with atrial fibrillation and a clinical suspicion of restless legs syndrome who were referred for polysomnography were divided into two groups based on severity of periodic leg movement during sleep: frequent (periodic movement index >35/h) and infrequent (≤35/h). Progression of atrial fibrillation to persistent or permanent forms between the two groups was compared using Wilcoxon rank-sum test, chi-square tests and logistic regression analysis. Of 373 patients with atrial fibrillation (77% paroxysmal, 23% persistent), 108 (29%) progressed to persistent or permanent atrial fibrillation during follow-up (median, 33 months; interquartile range, 16-50). Compared to patients with infrequent periodic leg movement during sleep (n=168), patients with frequent periodic leg movement during sleep (n=205) had a higher rate of atrial fibrillation progression (23% vs. 34%; p=0.01). Patients with frequent periodic leg movement during sleep were older and predominantly male; however, there were no significant differences at baseline in clinical factors that promote atrial fibrillation progression between both groups. On multivariate analysis, independent predictors of atrial fibrillation progression were persistent atrial fibrillation at baseline, female gender, hypertension and frequent periodic leg movement during sleep. In patients with frequent periodic leg movement during sleep, dopaminergic therapy for control of leg movements in patients with restless legs syndrome reduced risk of atrial fibrillation progression. Frequent leg movement during sleep in patients with restless legs syndrome is associated
Hatem, Stéphane N; Redheuil, Alban; Gandjbakhch, Estelle
The amount of adipose tissue that accumulates around the atria is associated with the risk, persistence, and severity of atrial fibrillation (AF). A strong body of clinical and experimental evidence indicates that this relationship is not an epiphenomenon but is the result of complex crosstalk between the adipose tissue and the neighbouring atrial myocardium. For instance, epicardial adipose tissue is a major source of adipokines, inflammatory cytokines, or reactive oxidative species, which can contribute to the fibrotic remodelling of the atrial myocardium. Fibro-fatty infiltrations of the subepicardium could also contribute to the functional disorganization of the atrial myocardium. The observation that obesity is associated with distinct structural and functional remodelling of the atria has opened new perspectives of treating AF substrate with aggressive risk factor management. Advances in cardiac imaging should lead to an improved ability to visualize myocardial fat depositions and to localize AF substrates.
... Atrial Fibrillation AGENCY: Agency for Healthcare Research and Quality (AHRQ), HHS. ACTION: Request for... scientific information submissions from manufacturers of atrial fibrillation medical devices. Scientific... Fibrillation, which is currently being conducted by the Evidence-based Practice Centers for the AHRQ...
Nam, Gi-Byoung; Jin, Eun-Sun; Choi, HyungOh; Song, Hae-Geun; Kim, Sung-Hwan; Kim, Ki-Hun; Hwang, Eui-Seock; Park, Kyoung-Min; Kim, Jun; Rhee, Kyoung-Suk; Choi, Kee-Joon; Kim, You-Ho
Catheter ablation of atrial fibrillation that targets complex fractionated electrogram sites has been widely applied in the management of persistent atrial fibrillation. The clinical outcomes of pulmonary vein isolation alone and pulmonary vein isolation plus the use of complex fractionated electrogram-guided ablation (CFEA) have not been fully compared in patients with paroxysmal atrial fibrillation. This prospective study included 70 patients with symptomatic paroxysmal atrial fibrillation that remained inducible after pulmonary vein isolation. For radio-frequency catheter ablation, patients were nonrandomly assigned to a control group (pulmonary vein isolation alone, Group 1, n=35) or a CFEA group (pulmonary vein isolation plus additional CFEA, Group 2, n=35). The times to first recurrence of atrial tachyarrhythmias were compared between the 2 groups. In Group 2, CFEA rendered atrial fibrillation noninducible in 16 patients (45.7%) and converted inducible atrial fibrillation into inducible atrial flutters in 12 patients (34.3%). Atrial fibrillation remained inducible in 7 patients (20%) after the combined ablation procedures. After a mean follow-up of 23 months, freedom from recurrence of atrial tachyarrhythmias was significantly higher in Group 2 than in Group 1 (P=0.037). In Group 1, all of the recurrent tachyarrhythmias were atrial fibrillation, whereas regular tachycardia was the major mechanism of recurrent arrhythmias in Group 2 (atrial tachycardia or atrial flutter in 5 of 6 patients and atrial fibrillation in 1 patient). We found that CFEA after pulmonary vein isolation significantly reduced recurrent atrial tachyarrhythmia and might modify the pattern of arrhythmia recurrence in patients with paroxysmal atrial fibrillation. PMID:22719147
McDowell, Kathleen S; Vadakkumpadan, Fijoy; Blake, Robert; Blauer, Joshua; Plank, Gernot; MacLeod, Rob S; Trayanova, Natalia A
Personalized computational cardiac models are emerging as an important tool for studying cardiac arrhythmia mechanisms, and have the potential to become powerful instruments for guiding clinical anti-arrhythmia therapy. In this article, we present the methodology for constructing a patient-specific model of atrial fibrosis as a substrate for atrial fibrillation. The model is constructed from high-resolution late gadolinium-enhanced magnetic resonance imaging (LGE-MRI) images acquired in vivo from a patient suffering from persistent atrial fibrillation, accurately capturing both the patient's atrial geometry and the distribution of the fibrotic regions in the atria. Atrial fiber orientation is estimated using a novel image-based method, and fibrosis is represented in the patient-specific fibrotic regions as incorporating collagenous septa, gap junction remodeling, and myofibroblast proliferation. A proof-of-concept simulation result of reentrant circuits underlying atrial fibrillation in the model of the patient's fibrotic atrium is presented to demonstrate the completion of methodology development. Copyright © 2012 Elsevier Inc. All rights reserved.
Masè, M; Marini, M; Disertori, M; Ravelli, F
The causal relationship between atrial and ventricular activities during human atrial fibrillation (AF) is poorly understood. This study analyzed the effects of an increase in atrial rate on the link between atrial and ventricular activities during AF. Atrial and ventricular time series were determined in 14 patients during the spontaneous acceleration of the atrial rhythm at AF onset. The dynamic relationship between atrial and ventricular activities was quantified in terms of atrioventricular (AV) coupling by AV synchrogram analysis. The technique identified n:m coupling patterns (n atrial beats in m ventricular cycles), quantifying their percentage, maximal length, and conduction ratio (= m/n). Simulations with a difference-equation AV model were performed to correlate the observed dynamics to specific atrial/nodal properties. The atrial rate increase significantly affected AV coupling and ventricular response during AF. The shortening of atrial intervals from 185 ± 32 to 165 ± 24 ms (P < 0.001) determined transitions toward AV patterns with progressively decreasing m/n ratios (from conduction ratio = 0.34 ± 0.09 to 0.29 ± 0.08, P < 0.01), lower occurrence (from percentage of coupled beats = 27.1 ± 8.0 to 21.8 ± 6.9%, P < 0.05), and higher instability (from maximal length = 3.9 ± 1.5 to 2.8 ± 0.7 s, P < 0.01). Advanced levels of AV block and coupling instability at higher atrial rates were associated with increased ventricular interval variability (from 123 ± 52 to 133 ± 55 ms, P < 0.05). AV pattern transitions and coupling instability in patients were predicted, assuming the filtering of high-rate irregular atrial beats by the slow recovery of nodal excitability. These results support the role of atrial rate in determining AV coupling and ventricular response and may have implications for rate control in AF.
Kik, Charles; Bogers, Ad J.J.C.
Atrial fibrillation may result in significant symptoms, (systemic) thrombo-embolism, as well as tachycardia-induced cardiomyopathy with cardiac failure, and consequently be associated with significant morbidity and mortality. Nowadays symptomatic atrial fibrillation can be treated with catheter-based ablation, surgical ablation or hybrid approaches. In this setting a fairly large number of surgical approaches and procedures are described and being practised. It should be clear that the Cox-maze procedure resulted from building up evidence and experience in different steps, while some of the present surgical approaches and techniques are being based only on technical feasibility with limited experience, rather than on a process of consequent methodology. Some of the issues still under debate are whether or not the maze procedure can be limited to the left atrium or even to isolation of the pulmonary veins or that bi-atrial procedures are indicated, whether or not cardiopulmonary bypass is to be applied and which route of exposure facilitates an optimal result. In addition, maze procedures are not procedures guide by electrophysiological mapping. At least in theory not in all patients all lesions of the maze procedures are necessary. A history and aspects of current practise in surgical treatment of atrial fibrillation is presented.
Trigo, Paula; Fischer, Gregory W
Atrial fibrillation is the most commonly seen arrhythmia in the geriatric population and is associated with increased cardiovascular morbidity and mortality. Treatment of the elderly with atrial fibrillation remains challenging for physicians, because this unique subpopulation is characterized by multiple comorbidities requiring chronic use of numerous medications, which can potentially lead to severe drug interactions. Furthermore, age-related changes in the cardiovascular system as well as other physiological changes result in altered drug pharmacokinetics. Dronedarone is a new drug recently approved for the treatment of arrhythmias, such as atrial fibrillation and/or atrial flutter. Dronedarone is a benzofuran amiodarone analog which lacks the iodine moiety and contains a methane sulfonyl group that decreases its lipophilicity. These differences in chemical structure are responsible for making dronedarone less toxic than amiodarone which, in turn, results in fewer side effects. Adverse events for dronedarone include gastrointestinal side effects and rash. No dosage adjustments are required for patients with renal impairment. However, the use of dronedarone is contraindicated in the presence of severe hepatic dysfunction.
Labombarda, Fabien; Hamilton, Robert; Shohoudi, Azadeh; Aboulhosn, Jamil; Broberg, Craig S; Chaix, Marie A; Cohen, Scott; Cook, Stephen; Dore, Annie; Fernandes, Susan M; Fournier, Anne; Kay, Joseph; Macle, Laurent; Mondésert, Blandine; Mongeon, François-Pierre; Opotowsky, Alexander R; Proietti, Anna; Rivard, Lena; Ting, Jennifer; Thibault, Bernard; Zaidi, Ali; Khairy, Paul
Atrial arrhythmias are the most common complication encountered in the growing and aging population with congenital heart disease. This study sought to assess the types and patterns of atrial arrhythmias, associated factors, and age-related trends. A multicenter cohort study enrolled 482 patients with congenital heart disease and atrial arrhythmias, age 32.0 ± 18.0 years, 45.2% female, from 12 North American centers. Qualifying arrhythmias were classified by a blinded adjudicating committee. The most common presenting arrhythmia was intra-atrial re-entrant tachycardia (IART) (61.6%), followed by atrial fibrillation (28.8%), and focal atrial tachycardia (9.5%). The proportion of arrhythmias due to IART increased with congenital heart disease complexity from 47.2% to 62.1% to 67.0% in patients with simple, moderate, and complex defects, respectively (p = 0.0013). Atrial fibrillation increased with age to surpass IART as the most common arrhythmia in those ≥50 years of age (51.2% vs. 44.2%; p < 0.0001). Older age (odds ratio [OR]: 1.024 per year; 95% confidence interval [CI]: 1.010 to 1.039; p = 0.001) and hypertension (OR: 2.00; 95% CI: 1.08 to 3.71; p = 0.029) were independently associated with atrial fibrillation. During a mean follow-up of 11.3 ± 9.4 years, the predominant arrhythmia pattern was paroxysmal in 62.3%, persistent in 28.2%, and permanent in 9.5%. Permanent atrial arrhythmias increased with age from 3.1% to 22.6% in patients <20 years to ≥50 years, respectively (p < 0.0001). IART is the most common presenting atrial arrhythmia in patients with congenital heart disease, with a predominantly paroxysmal pattern. However, atrial fibrillation increases in prevalence and atrial arrhythmias progressively become permanent as the population ages. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Ejima, Koichiro; Shoda, Morio; Tanizaki, Kohei; Kasanuki, Hiroshi
Irregular tachycardias mimicking atrial fibrillation (AF) have previously been described. We report a case of a 60-year-old man with an antiarrhythmic drug-resistant atrial tachycardia (AT) mimicking AF. The tachycardia consisted of two distinct ATs with interference of one repetitive AT with another sustained AT. Radiofrequency (RF) ablation of two distinct right atrial foci eliminated the irregular tachycardia. Although catheter-based pulmonary vein isolation has become a popular therapeutic approach for patients with symptomatic AF, careful evaluation of the intracardiac recordings in the patients undergoing RF ablation for AF is important.
Large, Stephen R; Nashef, Samer A M
Surgery to correct a structural heart valve problem can restore sinus rhythm in approximately one-fifth of patients with atrial fibrillation (AF), and the addition of a maze procedure will increase this proportion. Evidence shows that the maze procedure may restore atrial function in some patients and may have beneficial effects on functional symptoms and prognosis. The role of the maze procedure as an isolated treatment for lone AF in the context of heart failure with no structurally correctable cause is unknown. Future progress will determine the appropriate indications for treatment and the risks and benefits of any intervention.
The mechanisms underlying atrial fibrillation (AF) in humans are poorly understood. In particular, we simply do not understand how atrial AF becomes persistent or permanent. The objective of this brief review is to address the most important factors involved in the mechanism of AF perpetuation, including structural remodeling in the form of fibrosis and electrical remodeling secondary to ion channel expression changes. In addition, I discuss the possibility that both fibrosis and electrical remodeling might be preventable when intervening pharmacologically early enough before the remodeling process reaches a point of no return.
Robertson, Jason O.; Lawrance, Christopher P.; Maniar, Hersh S.; Damiano, Ralph J.
The use of surgical lesion sets for the treatment of atrial fibrillation has been increasing, particularly in patients with complicated anatomical substrates and those undergoing concomitant surgery. Preferences in terms of lesion set, surgical approach and ablation technology vary by center. This review discusses both the surgical techniques and the outcomes for the most commonly performed procedures in the context of recent consensus guidelines. The Cox-Maze IV, pulmonary vein isolation, extended left atrial lesion sets, the hybrid approach and ganglionated plexus ablation are each reviewed in an attempt to provide insight into current clinical practice and patient selection PMID:23823731
Pacifico, Antonio; Henry, Philip D
During the past 10 years numerous studies on the treatment of paroxysmal atrial fibrillation (AF) by right and left atrial ablation procedures have been published. The results of studies based on follow-up periods of a few months have been repeatedly interpreted as providing evidence for curative therapy. However, insufficient focus on the variability of the natural history of paroxysmal AF, the inadequate detection of silent arrhythmic events, the eclectic post-interventional use of antiarrhythmic drugs, and the lack of appropriate control groups make the reports unconvincing. Randomized controlled trials are needed to confirm postulated long-term cure rates for AF.
Cerasuolo, Joshua O; Montero-Odasso, Manuel; Ibañez, Agustin; Doocy, Shannon; Lip, Gregory Yh; Sposato, Luciano A
Atrial fibrillation affects 33.5 million people worldwide and its prevalence is expected to double by 2050 because of the aging population. Atrial fibrillation confers a 5-fold higher risk of ischemic stroke compared to sinus rhythm. We present our view of the role of shared medical decision-making to combat global underutilization of oral anticoagulation for stroke prevention in atrial fibrillation patients. Oral anticoagulation underuse is widespread as it is present within atrial fibrillation patients of all risk strata and in countries across all income levels. Reasons for oral anticoagulation underuse include but are probably not limited to poor risk stratification, over-interpretation of contraindications, and discordance between physician prescription preferences and actual administration. By comparing a catastrophic event to the consequences of atrial fibrillation related strokes, it may help physicians and patients understand the negative outcomes associated with oral anticoagulation under-utilization and the magnitude to which oral anticoagulations neutralize atrial fibrillation burden.
Xie, Xudong; Liu, Yanrong; Gao, Shilong; Wu, Bifeng; Hu, Xiaosheng; Chen, Junzhu
Chronic atrial fibrillation (AF) is characterized by a remodeling process with prominent atrial fibrosis. Fibrocytes, a bone marrow-derived population of fibroblast-like cells, have been placed at the center of a number of fibrosing conditions. The purpose of this study was to evaluate the contribution of fibrocytes to atrial fibrosis in patients with chronic AF and the possible mechanisms. We enrolled 22 consecutive valvular heart disease patients with chronic AF (>6 months: CAF group) and 15 valvular heart disease patients in sinus rhythm served as controls (SR group). Left atrial tissue samples were obtained during cardiac surgery. The infiltration of fibrocytes into the atrial interstitium was observed by confocal microscopy. The number of atrial fibrocytes was approximately three-fold higher in the CAF group compared with the SR controls, and positively correlated with both the atrial collagen volume fraction (r=0.713; P=0.0002) and the left atrial volume index (r=0.631; P=0.002). In the peripheral blood samples collected before the operation, approximately 2.5-fold higher percentage of circulating fibrocytes was identified in the CAF group. These fibrocytes showed a stronger proliferative capacity (≍2.5-fold) and higher level expression of collagen I and α-SMA (≍2-fold and 4-fold, respectively) compared with the SR controls. The results suggested that fibrocytes may be involved in atrial fibrosis in chronic AF through enhanced profibrotic characteristics.
Folla, Cynthia de Oliveira; Melo, Cinthia Cristina de Santana; Silva, Rita de Cassia Gengo E
To analyze predictive demographic and perioperative variables of postoperative atrial fibrillation in patients who underwent exclusively coronary artery bypass grafting. This was a retrospective cohort. We randomly selected 105 medical records of patients who underwent exclusively coronary artery bypass grafting in 2014. Demographic, clinical (preoperative and immediate postoperative) data and related with surgical procedure were collected from medical records. The occurrence of postoperative atrial fibrillation was considered until the third day after the surgery. Variables were analyzed using descriptive and inferential statistics. To identify predictive factors of postoperative atrial fibrillation we used a decision tree model with Classification and Regression Trees algorithm. Atrial fibrillation incidence was 19.0% (n=20). Patients with left atrial >40.5mm and aged >64.5 years were more likely to develop the arrhythmia during the post-surgical period. Left atrial diameter and advanced age were predictive factors of atrial fibrillation in patients who underwent exclusively coronary artery bypass grafting. Analisar as variáveis demográficas e perioperatórias preditivas de fibrilação atrial pós-operatória em pacientes brasileiros submetidos exclusivamente à cirurgia de revascularização do miocárdio. Trata-se de coorte retrospectiva. A amostra foi constituída de 105 prontuários de pacientes submetidos exclusivamente à revascularização do miocárdio no ano de 2014, selecionados aleatoriamente. Dados demográficos, clínicos (préoperatórios e do pós-operatório imediato) e relacionados ao procedimento cirúrgico foram coletados por meio de consulta ao prontuário. A ocorrência de fibrilação atrial no pós-operatório foi considerada até o terceiro dia após a cirurgia. As variáveis foram analisadas por estatística descritiva e inferencial. Para identificar os fatores preditivos de fibrilação atrial no pós-operatório, utilizou-se um
Ros, E; Mota, S; Fernández, F J; Toro, F J; Bernier, J L
Paroxysmal atrial fibrillation (PAF) is one of the most common heart arrhythmias. It is very difficult to detect unless an explicit Atrial Fibrillation episode occurs during the exploration. The present paper describes a number of low level parameters extracted from ECG traces where no Atrial Fibrillation process is present. The ability of this parameter set to characterize PAF patients is studied and discussed. Based on these parameters a modular automatic classification algorithm for PAF diagnosis is developed and evaluated.
Bridge, Francesca; Thijs, Vincent
The introduction of insertable cardiac monitoring devices has dramatically altered our understanding of the role of intermittent atrial fibrillation in cryptogenic stroke. In this narrative review we discuss the incidence, timing and relationship between atrial fibrillation and cryptogenic stroke, how to select patients for monitoring and the value and limitations of different monitoring strategies. We also discuss the role of empirical anticoagulation, and atrial fibrillation burden as a means of tailoring anticoagulation in patients at high risk of bleeding. PMID:27283276
Lee, S H; Ahn, H J; Yeon, S M; Yang, M; Kim, J A; Jung, D M; Park, J H
Atrial fibrillation is the most frequent arrhythmia after thoracic surgery and is associated with increased hospital costs, morbidity and mortality. In this study, we aimed to identify potentially modifiable risk factors for postoperative atrial fibrillation following lung resection surgery and to suggest possible measures to reduce risk. We retrospectively reviewed the medical records of 4731 patients who underwent lobectomy or more major lung resection over a 6-year period. Patients who developed atrial fibrillation postoperatively and required treatment were included in the postoperative atrial fibrillation group, while the remaining patients were assigned to the non-postoperative atrial fibrillation group. Risk factors for postoperative atrial fibrillation were analysed by multivariate analysis and propensity score matching. Overall, 12% of patients developed postoperative atrial fibrillation. Potentially modifiable risk factors for postoperative atrial fibrillation were excessive alcohol consumption (odds ratio (OR) = 1.48, 95% CI 1.08-2.02, p = 0.0140), red cell transfusion (2.70(2.13-3.43), p < 0.0001), use of inotropes (1.81(1.42-2.31), p < 0.0001) and open (vs. thoracoscopic) surgery (1.59(1.23-2.05), p < 0.0001). Compared with inotrope use, vasopressor administration was not related to postoperative atrial fibrillation. Use of steroids or thoracic epidural anaesthesia did not reduce the incidence of postoperative atrial fibrillation. We conclude that high alcohol consumption, red cell transfusion, use of inotropes and open surgery are potentially modifiable risk factors for postoperative atrial fibrillation. Pre-operative alcohol consumption needs to be addressed. Avoiding red cell transfusion and performing lung resection via video-assisted thoracoscopic surgery may reduce the incidence of postoperative atrial fibrillation and the administration of vasopressors rather than inotropes is preferred.
Almeida, Eduardo Dytz; Guimarães, Raphael Boesche; Stephan, Laura Siga; Medeiros, Alexandre Kreling; Foltz, Katia; Santanna, Roberto Tofani; Pires, Leonardo Martins; Kruse, Marcelo Lapa; Lima, Gustavo Glotz de; Leiria, Tiago Luiz Luz
Atrial fibrillation and atrial flutter account for one third of hospitalizations due to arrhythmias, determining great social and economic impacts. In Brazil, data on hospital care of these patients is scarce. To investigate the arrhythmia subtype of atrial fibrillation and flutter patients in the emergency setting and compare the clinical profile, thromboembolic risk and anticoagulants use. Cross-sectional retrospective study, with data collection from medical records of every patient treated for atrial fibrillation and flutter in the emergency department of Instituto de Cardiologia do Rio Grande do Sul during the first trimester of 2012. We included 407 patients (356 had atrial fibrillation and 51 had flutter). Patients with paroxysmal atrial fibrillation were in average 5 years younger than those with persistent atrial fibrillation. Compared to paroxysmal atrial fibrillation patients, those with persistent atrial fibrillation and flutter had larger atrial diameter (48.6 ± 7.2 vs. 47.2 ± 6.2 vs. 42.3 ± 6.4; p < 0.01) and lower left ventricular ejection fraction (66.8 ± 11 vs. 53.9 ± 17 vs. 57.4 ± 16; p < 0.01). The prevalence of stroke and heart failure was higher in persistent atrial fibrillation and flutter patients. Those with paroxysmal atrial fibrillation and flutter had higher prevalence of CHADS2 score of zero when compared to those with persistent atrial fibrillation (27.8% vs. 18% vs. 4.9%; p < 0.01). The prevalence of anticoagulation in patients with CHA2DS2-Vasc ≤ 2 was 40%. The population in our registry was similar in its comorbidities and demographic profile to those of North American and European registries. Despite the high thromboembolic risk, the use of anticoagulants was low, revealing difficulties for incorporating guideline recommendations. Public health strategies should be adopted in order to improve these rates.
Almeida, Eduardo Dytz; Guimarães, Raphael Boesche; Stephan, Laura Siga; Medeiros, Alexandre Kreling; Foltz, Katia; Santanna, Roberto Tofani; Pires, Leonardo Martins; Kruse, Marcelo Lapa; de Lima, Gustavo Glotz; Leiria, Tiago Luiz Luz
Introduction Atrial fibrillation and atrial flutter account for one third of hospitalizations due to arrhythmias, determining great social and economic impacts. In Brazil, data on hospital care of these patients is scarce. Objective To investigate the arrhythmia subtype of atrial fibrillation and flutter patients in the emergency setting and compare the clinical profile, thromboembolic risk and anticoagulants use. Methods Cross-sectional retrospective study, with data collection from medical records of every patient treated for atrial fibrillation and flutter in the emergency department of Instituto de Cardiologia do Rio Grande do Sul during the first trimester of 2012. Results We included 407 patients (356 had atrial fibrillation and 51 had flutter). Patients with paroxysmal atrial fibrillation were in average 5 years younger than those with persistent atrial fibrillation. Compared to paroxysmal atrial fibrillation patients, those with persistent atrial fibrillation and flutter had larger atrial diameter (48.6 ± 7.2 vs. 47.2 ± 6.2 vs. 42.3 ± 6.4; p < 0.01) and lower left ventricular ejection fraction (66.8 ± 11 vs. 53.9 ± 17 vs. 57.4 ± 16; p < 0.01). The prevalence of stroke and heart failure was higher in persistent atrial fibrillation and flutter patients. Those with paroxysmal atrial fibrillation and flutter had higher prevalence of CHADS2 score of zero when compared to those with persistent atrial fibrillation (27.8% vs. 18% vs. 4.9%; p < 0.01). The prevalence of anticoagulation in patients with CHA2DS2-Vasc ≤ 2 was 40%. Conclusions The population in our registry was similar in its comorbidities and demographic profile to those of North American and European registries. Despite the high thromboembolic risk, the use of anticoagulants was low, revealing difficulties for incorporating guideline recommendations. Public health strategies should be adopted in order to improve these rates. PMID:26016782
Ogata, Toshiyasu; Yasaka, Masahiro
The patients with cardioembolic stroke sometimes suffer from severe neurological deficit and from recurrent strokes. Since atrial fibrillation, especially non-valvular atrial fibrillation (NVAF) is associated with over half of the cardioembolic strokes, the prevention of cardioembolic stroke in patients with NVAF is important. There have been some reports about how to prevent stroke. They have indicated that the best medication for preventing from stroke was anticoagulation by warfarin. Therefore, the guidelines recommended the patients with NVAF to take warfarin. In case with the older patients under 70 years, prothrombin international normalized ratio (PT-INR) should be kept from 2.0 to 3.0. On the other hand, if the patients with NVAF are over 70 years, PT-INR has to be controlled from 1.6 to 2.6. Before extraction of a tooth, anticoagulation should not be call off.
Marcotte, Christopher D.; Grigoriev, Roman O.
While spiral wave breakup has been implicated in the emergence of atrial fibrillation, its role in maintaining this complex type of cardiac arrhythmia is less clear. We used the Karma model of cardiac excitation to investigate the dynamical mechanisms that sustain atrial fibrillation once it has been established. The results of our numerical study show that spatiotemporally chaotic dynamics in this regime can be described as a dynamical equilibrium between topologically distinct types of transitions that increase or decrease the number of wavelets, in general agreement with the multiple wavelets' hypothesis. Surprisingly, we found that the process of continuous excitation waves breaking up into discontinuous pieces plays no role whatsoever in maintaining spatiotemporal complexity. Instead, this complexity is maintained as a dynamical balance between wave coalescence—a unique, previously unidentified, topological process that increases the number of wavelets—and wave collapse—a different topological process that decreases their number.
Briongos Figuero, Sem; García Santos-Gallego, Carlos; Badimón, Juan José
For the last decades vitamin K antagonists have been the most effective anticoagulant treatment of atrial fibrillation. New molecules are being designed, mainly due to the great amount of disadvantages in the management of conventional anticoagulation. Dabigatran, rivaroxaban and apixaban will soon be available as an alternative to warfarin/acenocumarol. All of them have demonstrated to be non-inferior to warfarin in preventing stroke and systemic embolism, with even dabigatran 150 mg bid and apixaban being superior. They have also a lower risk of bleeding, especially regarding severe/fatal and intracranial hemorrhages. This is a real revolution. The advance of these new anticoagulants will be limited only by the higher cost, and will progressively become the protagonists of oral anticoagulation in patients with nonvalvular atrial fibrillation.
Korantzopoulos, Panagiotis; Li, Guangping
Atrial fibrillation (AF) is the most common sustained arrhythmia in clinical practice, representing a major public health problem. Recent evidence suggests oxidative stress may play an important role in the pathogenesis and perpetuation of AF. In the past few years, experimental data and clinical evidence have tested the concept of antioxidant therapies to prevent AF. Besides statins, ACE-inhibitors (ACEIs) and/or angiotensin-receptor blockers (ARBs), and omega-3 polyunsaturated fatty acids, several other interventions with antioxidant properties, such as Vitamin C and E, thiazolidinediones, N-acetylcysteine, probucol, nitric oxide donors or precursors, NADPH oxidase inhibitors, Xanthine oxidase inhibitors have emerged as novel strategies for the management of AF. We aim to review recent evidence regarding antioxidant therapies in the prevention and treatment of atrial fibrillation. PMID:24282730
Nguyen, Tuan; Jolly, Umjeet; Sidhu, Kiran; Yee, Raymond; Leong-Sit, Peter
Atrial fibrillation (AF) is an increasing global issue leading to increased hospitalizations, adverse health related events and mortality. This review focuses on the management of atrial fibrillation, in particular in the past decade, comparing two major strategies, rate or rhythm control. We evaluate the evidence for each strategy, pharmacological options and the increasing utilization of invasive techniques, in particular catheter ablation and use of implantable cardiac pacing devices. Pharmacological comparative trials evaluating both strategies have shown rate control being non-inferior to rhythm control for clinical outcomes of mortality and other cardiovascular events (including stroke). Catheter ablation techniques, involving radiofrequency ablation and recently cryoablation, have shown promising results in particular with paroxysmal AF. However, persistent AF provides ongoing challenges and will be a particular focus of continued research.
Gucuk Ipek, Esra; Marine, Joseph E; Habibi, Mohammadali; Chrispin, Jonathan; Lima, Joao; Rickard, Jack; Spragg, David; Zimmerman, Stefan L; Zipunnikov, Vadim; Berger, Ronald; Calkins, Hugh; Nazarian, Saman
Symptomatic left atrial (LA) flutter (LAFL) is common after atrial fibrillation (AF) ablation. The purpose of this study was to examine the association of baseline LA function with incident LAFL after AF ablation. The source cohort included 216 patients with cardiac magnetic resonance (CMR) before initial AF ablation between 2010 and 2013. Patients who underwent cryoballoon or laser ablation, patients with AF during CMR, and those with suboptimal CMR, or missing follow-up data were excluded. Baseline LA volume and function were assessed by feature-tracking CMR analysis. The final cohort included 119 patients (mean age 58.9 ± 11 years; 76.5% men; 70.6% patients with paroxysmal AF). During a median follow-up of 421 days (interquartile range 235-751 days), 22 patients (18.5%) had incident LAFL. Baseline LA volume was similar between the 2 groups. In contrast, baseline reservoir, conduit, and contractile function of the LA were significantly impaired in patients with incident LAFL. Baseline global peak longitudinal atrial strain (PLAS) <22.65% predicted incident LAFL with 86% sensitivity and 68% specificity (C statistic 0.76). In a multivariable model adjusting for age, heart failure, and LA volume, PLAS (hazard ratio 0.9 per % increase in PLAS; P = .003) and LA linear lesions (hazard ratio 2.94; P = .020) were independently associated with incident LAFL. The coexistence of PLAS <22.65% and linear lesions was associated with 9-fold increased hazard of incident LAFL. Baseline LA function and linear lesions were independently associated with incident LAFL after AF ablation. Linear lesions should be limited to selected cases, especially in patients with impaired LA function. Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.
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...
Zhang, Peide; Wang, Wei; Wang, Xin; Wang, Xu; Song, Yunhu; Han, Yong; Zhang, Jing; Zhao, Hui
Atrial fibrosis, as a hallmark of atrial structure remodeling, plays an important role in maintenance of chronic atrial fibrillation, but interrelationship of atrial fibrosis and atrial fibrillation is uncertain. Label-free proteomics can implement high throughput screening for finding and analyzing pivotal proteins related to the disease.. Therefore, we used label-free proteomics to explore and analyze differentially proteins in chronic atrial fibrillation patients with mitral valve disease. Left and right atrial appendages obtained from patients with mitral valve disease were both in chronic atrial fibrillation (CAF, AF≥6 months, n = 6) and in sinus rhythm (SR, n = 6). One part of the sample was used for histological analysis and fibrosis quantification; other part were analyzed by label-free proteomic combining liquid chromatography with mass spectrometry (LC-MS), we utilized bioinformatics analysis to identify differential proteins. Degree of atrial fibrosis was higher in CAF patients than that of SR patients. 223 differential proteins were detected between two groups. These proteins mainly had vital functions such as cell proliferation, stress response, focal adhesion apoptosis. We evaluated that serine/threonine protein kinase N2 (PKN2), dermatopontin (DP), S100 calcium binding protein B (S100B), protein tyrosine kinase 2 (PTK2) and discoidin domain receptor tyrosine kinase 2 (DDR2) played important roles in fibrotic process related to atrial fibrillation. The study presented differential proteins responsible for atrial fibrosis in chronic atrial fibrillation patients through label-free proteomic analysis. We assessed some vital proteins including their characters and roles. These findings may open up new realm for mechanism research of atrial fibrillation.
Estrada, Amara H; Pariaut, Romain; Moïse, N Sydney
Electrical cardioversion of atrial fibrillation is now commonly performed in veterinary medicine. Successful timing of the delivery of energy is important in order to avoid ventricular fibrillation. This brief communication describes how to ensure that proper energy delivery is performed.
Bogachev-Prokophiev, Alexandr; Zheleznev, Sergey; Romanov, Alexander; Pokushalov, Evgeny; Pivkin, Alexey; Corbucci, Giorgio; Karaskov, Alexander
Continuous monitoring of cardiac rhythm may play an important role in measuring the true symptomatic/asymptomatic atrial fibrillation (AF) burden and improve the management of anti-arrhythmic and anti-thrombotic therapies. Forty-seven patients with mitral valve disease and longstanding persistent AF (LSPAF) underwent a left atrial maze procedure with bipolar radiofrequency and valve surgery. The follow-up data recorded by an implanted loop recorder were analysed after 3, 6 and 12 months. On discharge, 40 (85.1%) patients were in stable sinus rhythm, as documented by in-office electrocardiography (ECG), 4 (8.5%) were in pacemaker rhythm and 3 (6.4%) were in AF. One (2.1%) patient died after 7 months. On 12-month follow-up examination, 30 (65.2%) patients had an AF burden <0.5% and were classified as responders. Three (6.5%) of the 16 non-responders had atrial flutter and 13 (27.7%) had documented AF recurrences with an AF burden >0.5%. Two (4.3%) patients with AF recurrences were completely asymptomatic. Among the symptomatic events stored by the patients, only 27.6% was confirmed as genuine AF recurrences according to the concomitant ECG recorded by the implanted loop recorder. A concomitant bipolar maze procedure during mitral valve surgery is effective in treating AF, as proved by detailed 1-year continuous monitoring.
Bogachev-Prokophiev, Alexandr; Zheleznev, Sergey; Romanov, Alexander; Pokushalov, Evgeny; Pivkin, Alexey; Corbucci, Giorgio; Karaskov, Alexander
Continuous monitoring of cardiac rhythm may play an important role in measuring the true symptomatic/asymptomatic atrial fibrillation (AF) burden and improve the management of anti-arrhythmic and anti-thrombotic therapies. Forty-seven patients with mitral valve disease and longstanding persistent AF (LSPAF) underwent a left atrial maze procedure with bipolar radiofrequency and valve surgery. The follow-up data recorded by an implanted loop recorder were analysed after 3, 6 and 12 months. On discharge, 40 (85.1%) patients were in stable sinus rhythm, as documented by in-office electrocardiography (ECG), 4 (8.5%) were in pacemaker rhythm and 3 (6.4%) were in AF. One (2.1%) patient died after 7 months. On 12-month follow-up examination, 30 (65.2%) patients had an AF burden <0.5% and were classified as responders. Three (6.5%) of the 16 non-responders had atrial flutter and 13 (27.7%) had documented AF recurrences with an AF burden >0.5%. Two (4.3%) patients with AF recurrences were completely asymptomatic. Among the symptomatic events stored by the patients, only 27.6% was confirmed as genuine AF recurrences according to the concomitant ECG recorded by the implanted loop recorder. A concomitant bipolar maze procedure during mitral valve surgery is effective in treating AF, as proved by detailed 1-year continuous monitoring. PMID:22514258
Atrial fibrillation (AF) is a common arrhythmia of substantial public health importance. Recent evidence demonstrates a heritable component underlying AF, and genetic discoveries have identified common variants associated with the arrhythmia. Ultimately one hopes that the consideration of genetic variation in clinical practice may enhance care and improve health outcomes. In this review we explore areas of potential clinical utility in AF management including those relating to pharmacogenetics and risk prediction. PMID:23210687
Pirson, Magali; Di Pierdomenico, Lionel; Gusman, Julie; Baré, Benoît; Fontaine, David; Motte, Serge
The number of hospitalizations for atrial fibrillation has increased dramatically. This increase, in the number of hospital stays will continue, given the growth projections based on epidemiological data, and will contribute to significantly increase expenses for the social security system.The objective of this study was to evaluate the length of hospital stay, the average cost borne by social security, and the types of hospital stay expenditures for patients admitted through the emergency department for atrial fibrillation. Patients were identified by using the minimal clinical summaries of seven general hospitals in Belgium in 2008. Only hospitalized patients having as primary diagnosis code ICD-9-CM 42731 'atrial fibrillation'were selected for this study. Hospital billing files were analysed in order to isolate the costs borne by social security. Outliers were isolated in order not to have results influenced by patients having an atypical length of stay. Results show that the mean length of stay was 8.6 days and the mean cost charged to social security was euro 3,066.02 per hospital stay.The mean cost of care was strongly associated with the degree of severity index related to the APR-DRG. Approximately 85% of the total cost was related to the cost of hospital days and medical procedures with medical imaging and laboratory tests being the two main cost inductors. 18% of patients had cardioversion during their hospital stay, including 4% who had only that treatment. 19% of patients used amiodarone. Flecainide and propafenone were also used, but less frequently. The mean cost of care for AF patients admitted via the emergency department is strongly associated with the degree of severity. Approximately 85% of the total cost is related to the cost of hospital days and medical procedures. Hypertension is the most common secondary diagnosis. An optimal treatment of this risk factor could help to reduce the risk of atrial fibrillation, and thereby reduce the morbidity
Bohnker, B K; Feeks, E F; McEwen, G
A patient is presented with new-onset atrial fibrillation. While being air-evacuated, he cardioverted during the acceleration associated with aircraft carrier catapult launch. This case suggests a possible myocardial response to the kinetic energy produced by the acceleration force, similar to the electrical energy commonly used for cardioversion. Cardioversion using acceleration forces is probably not a clinically useful modality; however, this case demonstrates the importance of acceleration forces on patients during medical evacuation from aircraft carriers.
Joseph, Jubin; Wong, Kelvin C K; Ginks, Matthew R; Bashir, Yaver; Betts, Timothy R; Rajappan, Kim
Steerable sheaths have been shown to reduce procedure time in the catheter ablation of atrial fibrillation (AF), where catheter positioning and stability is typically challenging. This review critically addresses and highlights the recent developments in design of sheaths used to manipulate the ablation catheter and how these developments may impact on the ablation procedure itself, in particular the likelihood of first-time success. Patents relating to steerable sheaths are reviewed and discussed to gauge potential future developments in this area.
Luckie, M; Jenkins, N P; Davidson, N C; Chauhan, A
Dressler's syndrome, characterized by features of fever, pericarditis and pericardial effusion typically occurs in the weeks to months following a myocardial infarction. The syndrome has also been described following several other myocardial and pericardial pathologies, including two reports of Dressler's syndrome following radio-frequency ablation. We describe a case of Dressler's syndrome following a pulmonary vein isolation procedure, which is being performed with increasing frequency as a treatment strategy for atrial fibrillation.
Anticoagulation is vital for stroke and systemic embolism prevention in patients with atrial fibrillation. Current therapy with the vitamin K inhibitor warfarin has many inherent limitations in clinical practice. With the potential of broadening anticoagulation therapy to a larger population, new classes of anticoagulants have recently emerged with the potential for improved efficacy, safety and convenience. Direct thrombin inhibitor and Factor Xa inhibitor classes are showing promise for both patients and clinicians. PMID:23251767
Sullivan, Renee M; Olshansky, Brian
Introduction: Dronedarone, a benzofuran derivative with a structure similar to amiodarone, has been developed as a potential therapy for patients with atrial fibrillation. Aim: To review the published evidence regarding the efficacy and safety of dronedarone use in patients with atrial fibrillation. Evidence review: Available evidence suggests that dronedarone 400 mg orally twice daily can lengthen the time to and decrease the overall recurrence of atrial fibrillation compared with placebo. Dronedarone may reduce risk of mortality and cardiovascular hospitalization. Patients with atrial fibrillation receiving dronedarone had improved ventricular rate control compared with patients receiving placebo. Dronedarone is associated with few serious adverse events except, notably, in patients with decompensated heart failure. Place in therapy: Dronedarone may have a role in rate and rhythm control for patients with atrial fibrillation. Dronedarone can reduce unique, but potentially serious, end points in patients with atrial fibrillation. Despite this, the exact role of dronedarone in the management of patients with atrial fibrillation continues to emerge. It remains uncertain if dronedarone should be considered a primary treatment strategy for atrial fibrillation. Dronedarone should not be administered to patients with decompensated heart failure. Conclusion: Dronedarone is a unique drug that may serve a key role to treat patients with atrial fibrillation. PMID:21042542
Atrial Fibrillation; Medication Adherence; Blood Coagulation Tests; Anticoagulants; Circulating, Hemorrhagic Disorder; Drug Effect; Drug Use; Drug Toxicity; Drug Intolerance; Blood Clot; Blood Coagulation Disorder; Laboratory Problem; Bleeding; Thrombosis
Doggrell, Sheila A
Subjects with atrial fibrillation are at risk of thromboembolic events. The vitamin K antagonists (e.g., warfarin) are useful at preventing coagulation in atrial fibrillation, but are difficult to use. One of the FXa inhibitors, oral apixaban, has been tested as an anticoagulant in atrial fibrillation. In ARISTOTLE (Apixaban for reduction in stroke and other thromboembolic events in atrial fibrillation) apixaban was compared to warfarin in subjects with atrial fibrillation, and shown to cause a lower rate of stroke or systemic embolism and of major bleeding, than warfarin. In the AVERROES (Apixaban versus acetylsalicylic acid [ASA] to prevent stroke in atrial fibrillations patients who have failed or are unsuitable for vitamin K antagonist treatment) trial, stroke or systemic embolism occurred less often with apixaban than aspirin, whereas the occurrence of major bleeding was similar in the groups. Apixaban is much easier for subjects with atrial fibrillation to use than warfarin, as it does not require regular monitoring by a health professional, with dosage adjustment. In addition to replacing warfarin in subjects with atrial fibrillation who are unable or not prepared to use warfarin, apixaban has the potential to replace warfarin more widely in the prevention of thromboembolism in subjects with atrial fibrillation.
Pinho-Gomes, Ana C; Amorim, Mário J; Oliveira, Sílvia M; Azevedo, Luís; Almeida, Jorge; Monteiro, Vítor; Maciel, Maria Júlia; Pinho, Paulo; Leite-Moreira, Adelino F
We present the experience of our centre with radiofrequency ablation of atrial fibrillation concomitantly with cardiac surgery Methods: 170 patients underwent atrial fibrillation ablation with uni/bipolar-radiofrequency. They were followed for 3-months and then as appropriate for the cardiac disease. In 2013, patients still alive underwent rhythm monitoring with ECG and 24-hour tape if in sinus rhythm Mean age was 65 years old and 42% of the patients were male. Paroxysmal AF was rare (7%). Most patients had preserved ejection fraction and dilated left atria (diameter 53.2±7.5 mm). The most common indication for cardiac surgery was valve disease. More than 75% of the patients underwent prophylactic closure of the left atrial appendage. Pulmonary vein isolation was performed in all patients, followed by other left atrial ablation lines. Overall, surgical complications were rare, being the most frequent pacemaker implantation (15%). Median length of stay was 9 days (p25-p75:7-14). At discharge, 69% of the patients were in sinus rhythm, being 90% on anticoagulation and 69% on amiodarone. In-hospital mortality was less than 3% (5 patients), none of them related to the ablation procedure. At 3 months, 50% of the patients were in sinus rhythm, being 92% on anticoagulation and 75% on antiarrhythmic drugs. Direct current cardioversion was successful in 8 of 12 patients. In the multivariate analysis, being in sinus rhythm at discharge was the single independent predictor of maintaining sinus rhythm at 3 months. In 2013 (469 patients-year), 40% of the patients were in sinus rhythm, being 80% on anticoagulation and 45% on antiarrhythmic drugs. Concurrent atrial fibrillation ablation with radiofrequency achieves satisfactory and stable recovery of sinu rhythm without adding significant operative risk and post-operative complications.
Sargento-Freitas, Joao; Silva, Fernando; Koehler, Sebastian; Isidoro, Luís; Mendonça, Nuno; Machado, Cristina; Cordeiro, Gustavo; Cunha, Luís
Cardioembolism due to atrial fibrillation assumes a dominant etiologic role in cerebrovascular diseases due to its growing incidence, high embolic risk and particular aspects of clinical events caused. Our objectives are to analyze the frequency of atrial fibrillation in patients with ischemic stroke, study the vital and functional impact of stroke due to different etiologies and evaluate antithrombotic options before and after stroke. We conducted a retrospective study including patients admitted in a central hospital due to ischemic stroke in 2010 (at least one year of follow-up). Etiology of stroke was defined using the Trial of ORG 10172 in Acute Stroke (TOAST) classification, and functional outcome by modified Rankin scale. We performed a descriptive analysis of different stroke etiologies and antithrombotic medication in patients with atrial fibrillation. We then conducted a cohort study to evaluate the clinical impact of antithrombotic options in secondary prevention after cardioembolic stroke. In our population (n = 631) we found superior frequency of cardioembolism (34.5%) to that reported in the literature. Mortality, morbidity and antithrombotic options are similar to other previous series, confirming the severity of cardioembolic strokes and the underuse of vitamin K antagonists. Oral anticoagulation was effective in secondary prevention independently from post-stroke functional condition. Despite unequivocal recommendations, oral anticoagulation is still underused in stroke prevention. This study confirms the clinical efficacy of vitamin K antagonists in secondary prevention independently from residual functional impairment.
Arotaritei, D.; Rotariu, C.
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%).
Filos, D; Chouvarda, I; Dakos, G; Vassilikos, V; Maglaveras, N
Atrial fibrillation (AF) is a complex phenomenon, related with a multitude of factors, including the electrical properties of the atrial substrate. The purpose of this work is to present a method that highlights electrocardiographic differences between normal subjects and patients with paroxysmal AF episodes (PAF), potentially related with substrate differences. Vectorcardiography recordings are considered and, for each lead (X-Y-Z), on a beat by beat basis, a steady window before QRS, corresponding to the atrial activity, is analysed via continuous wavelet transform. Wavelet-based parameters are calculated and compared between the normal and AF group, with the beat to beat variation of wavelet energy as the most important feature showing a significantly higher variability in the AF group.
Lau, Y-F; Yiu, K-H; Siu, C-W; Tse, H-F
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.
Mody, Behram P.; Raza, Anoshia; Jacobson, Jason; Iwai, Sei; Frenkel, Daniel; Rojas, Rhadames
Atrial fibrillation (AF) is the most commonly encountered arrhythmia in the clinical setting affecting nearly 6 million people in United States and the numbers are only expected to rise as the population continues to age. Broadly it is classified into paroxysmal, persistent and longstanding persistent AF. Electrical, structural and autonomic remodeling are some of the diverse pathophysiological mechanisms that contribute to the persistence of AF. Our review article emphasizes particularly on long standing persistent atrial fibrillation (LSPAF) aspect of the disease which poses a great challenge for electrophysiologists. While pulmonary vein isolation (PVI) has been established as a successful ablation strategy for paroxysmal AF, same cannot be said for LSPAF owing to its long duration, complexity of mechanisms, multiple triggers and substrate sites that are responsible for its perpetuation. The article explains different approaches currently being adopted to achieve freedom from atrial arrhythmias. These mainly include ablation techniques chiefly targeting complex fractionated atrial electrograms (CFAE), rotors, linear lesions, scars and even considering hybrid approaches in a few cases while exploring the role of delayed enhancement magnetic resonance imaging (deMRI) in the pre-procedural planning to improve the overall short and long term outcomes of catheter ablation. PMID:28856145
Friberg, L; Hammar, N; Rosenqvist, M
Recent studies of patients with heart failure and of patients receiving intensive care indicate that digoxin may increase mortality if the patient has atrial fibrillation (AF). Objective To study which patients receive digoxin treatment for AF and what the prognosis is for patients given this treatment. 2824 patients with AF were studied prospectively for a mean of 4.6 years. Information about medication was obtained from the local hospital registry. Information about diagnoses, hospitalisations and deaths was obtained from national registries. Propensity score matching and Cox regression was used to account for confounding. Factors associated with digoxin use were permanent AF (hazard ratio (HR) = 3.2, confidence interval (CI) 2.7 to 3.9), absence of pacemaker (HR = 2.3, CI 1.6 to 3.2), history of heart failure (HR = 2.0, CI 1.7 to 2.5), treatment in an internal medicine ward rather than a cardiology ward (HR = 1.6, CI 1.3 to 2.0), female sex (HR = 1.6, CI 1.3 to 1.9) and age >or=80 years (HR = 1.4, CI 1.1 to 1.7). More patients with than without digoxin died (51% vs 31%, p<0.001). After adjustment for covariates, however, no disadvantages related to digoxin use could be found for all-cause mortality, myocardial infarction, ischaemic stroke, time to readmission to hospital or days at hospital/year at risk. The only end point significantly associated with digoxin use was pacemaker implantations, which were more common in digoxin-treated patients (HR = 2.0, CI 1.2 to 3.4). Digoxin is mainly given to an elderly and frailer subset of patients with AF and is thus associated with an increased mortality. When differences in patient characteristics are accounted for digoxin use seems to have a neutral effect on mortality and major cardiovascular events in patients with AF.
Yamazaki, Masatoshi; Mironov, Sergey; Taravant, Clément; Brec, Julien; Vaquero, Luis M.; Bandaru, Krishna; Avula, Uma Mahesh R; Honjo, Haruo; Kodama, Itsuo; Berenfeld, Omer; Kalifa, Jérôme
Aims Atrial dilatation and myocardial stretch are strongly associated with atrial fibrillation (AF). However, the mechanisms by which the three-dimensional (3D) atrial architecture and heterogeneous stretch contribute to AF perpetuation are incompletely understood. We compared AF dynamics during stretch-related AF (pressure: 12cmH2O) in normal sheep hearts (n = 5) and in persistent AF (PtAF, n = 8)-remodelled hearts subjected to prolonged atrial tachypacing. We hypothesized that, in the presence of stretch, meandering 3D atrial scroll waves (ASWs) anchor in regions of large spatial gradients in wall thickness. Methods and results We implemented a high-resolution optical mapping set-up that enabled simultaneous epicardial- and endoscopy-guided endocardial recordings of the intact atria in Langendorff-perfused normal and PtAF (AF duration: 21.3 ± 11.9 days) hearts. The numbers and lifespan of long-lasting ASWs (>3 rotations) were greater in PtAF than normal (lifespan 0.9 ± 0.5 vs. 0.4 ± 0.2 s/(3 s of AF), P< 0.05). Than normal hearts, focal breakthroughs interacted with ASWs at the posterior left atrium and left atrial appendage to maintain AF. In PtAF hearts, ASW filaments seemed to span the atrial wall from endocardium to epicardium. Numerical simulations using 3D atrial geometries (Courtemanche-Ramirez-Nattel human atrial model) predicted that, similar to experiments, filaments of meandering ASWs stabilized at locations with large gradients in myocardial thickness. Moreover, simulations predicted that ionic remodelling and heterogeneous distribution of stretch-activated channel conductances contributed to filament stabilization. Conclusion The heterogeneous atrial wall thickness and atrial stretch, together with ionic and anatomic remodelling caused by AF, are the main factors allowing ASW and AF maintenance. PMID:22227155
Verrier, Richard L; Fuller, Henrique; Justo, Fernanda; Nearing, Bruce D; Rajamani, Sridharan; Belardinelli, Luiz
Detection of atrial repolarization waves free of far-field signal contamination by ventricular activation would allow investigation of atrial electrophysiology and factors that influence susceptibility to atrial tachycardia and atrial fibrillation (AF). The purpose of this study was to identify means for high-resolution intracardiac recording of atrial repolarization (Ta) waves using standard clinical electrocatheters and to assess fundamental electrophysiologic properties relevant to AF risk. In alpha-chloralose anesthetized Yorkshire pigs, we studied effects of vagus nerve stimulation (VNS) on PTa and QT intervals and effects of acute atrial ischemia or administration of intrapericardial acetylcholine followed by intravenous epinephrine on susceptibility to AF. Electrocatheters with closely spaced (1-mm) electrode pairs yielded high-resolution tracings of atrial repolarization waves. These recordings permitted detection of differential effects of right or left VNS, which shortened atrial PTa interval by 30% vs. 21% (P <.01) and lengthened QT interval by 1.5% vs. 9%, respectively (P < .05). During atrial ischemia, STa segments were elevated 3.4-fold (P < .01), and the threshold for inducing AF was reduced 3.1-fold (P = .004). Ischemia amplified atrial T-wave alternans (TWAa) and spatiotemporal heterogeneity (TWHa) by 23- and 13-fold, respectively, in inverse correlation to AF threshold (r = 0.74, P <.01; r = 0.61, P = .03). TWAa and TWHa increased by 4.5- and 2-fold shortly before autonomically triggered atrial premature beats and AF. This study used standard electrocatheters to demonstrate that TWAa and TWHa analysis provides means to assess vulnerability to AF without provocative electrical stimuli. These parameters could be evaluated in the clinical electrophysiology laboratory to determine risk for this prevalent arrhythmia and efficacy of contemporary and new agents. Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.
Xu, Zhen-Xing; Zhong, Jing-Quan; Zhang, Wei; Yue, Xin; Rong, Bing; Zhu, Qing; Zheng, Zhaotong; Zhang, Yun
This study aimed to assess whether intra- and inter-atrial conduction delay could predict atrial fibrillation (AF) for paroxysmal supraventricular tachycardia (PSVT) patients after successful treatment by radiofrequency catheter ablation (RFCA). Echocardiography examination was performed on 524 consecutive PSVT patients (15 patients were excluded). Left atrial dimension, right atrial diameter and intra- and inter-atrial conduction delay were measured before ablation. Patients were divided into group A (n = 32): occurrence of AF after the ablation and group B (n = 477): remained in sinus rhythm during follow-up. Receiver operating characteristic (ROC) curve analysis was performed to estimate the predictive value of intra- and inter-atrial conduction delay. Both intra- and inter-atrial conduction delay were higher in group A than in group B (4.79 ± 0.30 msec vs. 4.56 ± 0.32 msec; 21.98 ± 1.32 msec vs. 20.01 ± 1.33; p < 0.05). Binary logistic regression analysis showed that intra- and inter-atrial conduction were significant influential factors for the occurrence of AF (odds ratio [OR] = 13.577, 95% confidence interval [CI], 3.469-48.914; OR = 2.569, 95% CI, 1.909-3.459, p < 0.05). The ROC cure analysis revealed that intra-atrial conduction delay ≥ 4.45 msec and inter-atrial conduction delay ≥ 20.65 were the most optimal cut-off value for predicting AF in PSVT patients after RFCA. In conclusion, this is the first study to show that the intra- and inter-atrial conduction delay could effectively predict AF in post-ablation PSVT patients.
Berisso, Massimo Zoni; Fabbri, Gianna; Gonzini, Lucio; Caruso, Davide; Fontanella, Andrea; Pellegrini, Francesco; Silvestri, Nunzia; Vincenti, Antonio; Mathieu, Giovanni; Di Pasquale, Giuseppe
To provide insights on the antiarrhythmic management of atrial fibrillation among patients enrolled in the Antithrombotic Agents in Atrial Fibrillation (ATA-AF) study, and to assess the adherence of the Italian cardiologists and internists to guidelines recommendations. The ATA-AF study is a multicenter, observational study with prospective data collection on the management and treatment of patients with atrial fibrillation. From March to July 2010, 6910 patients with atrial fibrillation were recruited in 164 Italian Cardiology (Card) and 196 Internal Medicine (IMed) centers. Permanent atrial fibrillation was diagnosed in 50.8%, persistent atrial fibrillation in 24.4%, paroxysmal in 15.5%, and first-detected atrial fibrillation in 9.3% of the patients. Rhythm control (rhyC) strategy was pursued in 27.5% (39.6% Card vs. 12.9% IMed; P < 0.0001) and rate control (raC) in 51.4% (43.7% Card vs. 60.7% IMed; P < 0.0001); in 21.1% the antiarrhythmic strategy was not defined. Patients assigned to rhyC were younger and with less comorbidities than those assigned to raC. Adjusted multivariable analysis showed that atrial fibrillation type, setting of management, age and site of patient discharge were the most important independent predictors of rhyC assignment. The severity of atrial fibrillation-related symptoms was not associated with rhyC assignment. At discharge, beta-blockers, amiodarone and class 1c antiarrhythmic drugs were the drugs mainly used in the Card centers; and beta-blockers, digitalis, amiodarone and diltiazem/verapamil were used in the IMed centers. Amiodarone was overused in both Card and IMed centers. In the present study, rhyC was the strategy mainly pursued by cardiologists and raC by internists; treatment strategy assignment and antiarrhythmic therapy often do not agree with the guideline recommendations.
Accuracy of diagnosing atrial fibrillation on electrocardiogram by primary care practitioners and interpretative diagnostic software: analysis of data from screening for atrial fibrillation in the elderly (SAFE) trial.
Mant, Jonathan; Fitzmaurice, David A; Hobbs, F D Richard; Jowett, Sue; Murray, Ellen T; Holder, Roger; Davies, Michael; Lip, Gregory Y H
To assess the accuracy of general practitioners, practice nurses, and interpretative software in the use of different types of electrocardiogram to diagnose atrial fibrillation. Prospective comparison with reference standard of assessment of electrocardiograms by two independent specialists. 49 general practices in central England. 2595 patients aged 65 or over screened for atrial fibrillation as part of the screening for atrial fibrillation in the elderly (SAFE) study; 49 general practitioners and 49 practice nurses. All electrocardiograms were read with the Biolog interpretative software, and a random sample of 12 lead, limb lead, and single lead thoracic placement electrocardiograms were assessed by general practitioners and practice nurses independently of each other and of the Biolog assessment. Sensitivity, specificity, and positive and negative predictive values. General practitioners detected 79 out of 99 cases of atrial fibrillation on a 12 lead electrocardiogram (sensitivity 80%, 95% confidence interval 71% to 87%) and misinterpreted 114 out of 1355 cases of sinus rhythm as atrial fibrillation (specificity 92%, 90% to 93%). Practice nurses detected a similar proportion of cases of atrial fibrillation (sensitivity 77%, 67% to 85%), but had a lower specificity (85%, 83% to 87%). The interpretative software was significantly more accurate, with a specificity of 99%, but missed 36 of 215 cases of atrial fibrillation (sensitivity 83%). Combining general practitioners' interpretation with the interpretative software led to a sensitivity of 92% and a specificity of 91%. Use of limb lead or single lead thoracic placement electrocardiograms resulted in some loss of specificity. Many primary care professionals cannot accurately detect atrial fibrillation on an electrocardiogram, and interpretative software is not sufficiently accurate to circumvent this problem, even when combined with interpretation by a general practitioner. Diagnosis of atrial fibrillation in
Kuck, Karl-Heinz; Brugada, Josep; Fürnkranz, Alexander; Metzner, Andreas; Ouyang, Feifan; Chun, K R Julian; Elvan, Arif; Arentz, Thomas; Bestehorn, Kurt; Pocock, Stuart J; Albenque, Jean-Paul; Tondo, Claudio
Current guidelines recommend pulmonary-vein isolation by means of catheter ablation as treatment for drug-refractory paroxysmal atrial fibrillation. Radiofrequency ablation is the most common method, and cryoballoon ablation is the second most frequently used technology. We conducted a multicenter, randomized trial to determine whether cryoballoon ablation was noninferior to radiofrequency ablation in symptomatic patients with drug-refractory paroxysmal atrial fibrillation. The primary efficacy end point in a time-to-event analysis was the first documented clinical failure (recurrence of atrial fibrillation, occurrence of atrial flutter or atrial tachycardia, use of antiarrhythmic drugs, or repeat ablation) following a 90-day period after the index ablation. The noninferiority margin was prespecified as a hazard ratio of 1.43. The primary safety end point was a composite of death, cerebrovascular events, or serious treatment-related adverse events. A total of 762 patients underwent randomization (378 assigned to cryoballoon ablation and 384 assigned to radiofrequency ablation). The mean duration of follow-up was 1.5 years. The primary efficacy end point occurred in 138 patients in the cryoballoon group and in 143 in the radiofrequency group (1-year Kaplan-Meier event rate estimates, 34.6% and 35.9%, respectively; hazard ratio, 0.96; 95% confidence interval [CI], 0.76 to 1.22; P<0.001 for noninferiority). The primary safety end point occurred in 40 patients in the cryoballoon group and in 51 patients in the radiofrequency group (1-year Kaplan-Meier event rate estimates, 10.2% and 12.8%, respectively; hazard ratio, 0.78; 95% CI, 0.52 to 1.18; P=0.24). In this randomized trial, cryoballoon ablation was noninferior to radiofrequency ablation with respect to efficacy for the treatment of patients with drug-refractory paroxysmal atrial fibrillation, and there was no significant difference between the two methods with regard to overall safety. (Funded by Medtronic; FIRE
Obremska, Marta; Zyśko, Dorota; Nowicki, Rafał; Goździk, Anna; Rachwalik, Maciej; Grzebieniak, Tomasz; Kustrzycki, Wojciech
Chronic atrial fibrillation may temporarily resolve after cardiac surgery. Prolongation of the ventricular repolarization period may be the electrophysiological background for this phenomenon. The aim of the study was to assess the association between resolution of atrial fibrillation and changes in the duration of the ventricular repolarization period in patients with pre-operative chronic atrial fibrillation who underwent cardiac surgery. A retrospective analysis of the medical recordings of patients with chronic atrial fibrillation who underwent cardiac surgery was performed. After exclusions the study group comprised 51 patients with chronic atrial fibrillation who underwent surgery in the Cardiac Surgery Department of Wrocław Medical University in 2008 and 2009. The 12-lead EKGs performed before and after the surgery were assessed and the QT and R-R intervals were measured. The patients were divided into Group 1, in whom atrial fibrillation persisted after the cardiac surgery, and Group 2, whose atrial fibrillation resolved after the surgery. In 31 patients (60.8%) atrial fibrillation disappeared during the first 24 hours after cardiac surgery. A significant prolongation of the QT interval after the surgery was found in Group 2 that was not observed in Group 1. Multiple regression analysis revealed that QT interval duration after surgery is related to the resolution of atrial fibrillation independently from the duration of the R-R interval duration and the need for cardiac pacing. Spontaneous temporary resolution of atrial fibrillation is a common finding after cardiac surgery in patients with chronic atrial fibrillation. This phenomenon is related to a prolonged QT interval, therefore it may have an electrophysiological basis rather than a hemodynamic background. Further studies are required to assess the clinical importance of the prolongation of the QT interval after cardiac surgery.
Hravnak, Marilyn; Hoffman, Leslie A.; Saul, Melissa I.; Zullo, Thomas G.; Whitman, Gayle R.
Background Studies of resource utilization by patients with new-onset atrial fibrillation after coronary artery bypass grafting have addressed only length of stay and bed charges. Objective To compare resource utilization between patients with new-onset atrial fibrillation and patients without atrial fibrillation after isolated coronary artery bypass grafting. Methods Retrospective review of clinical and administrative electronic databases for 720 subjects who underwent isolated coronary artery bypass grafting with cardiopulmonary bypass in 25 months at one medical center. The prevalence of atrial fibrillation was determined, and resource utilization in various hospital cost centers was compared between subjects with and without atrial fibrillation. Results The prevalence of new-onset atrial fibrillation was 33.1%. Compared with subjects without atrial fibrillation, subjects with atrial fibrillation had a longer stay (5.8 ± 2.4 vs 4.4 ± 1.2 days, P< .001), more days receiving mechanical ventilation (P=.002) and oxygen therapy (P< .001), and higher rates of readmission to the intensive care unit (4.6% vs 0.2%, P< .001). Subjects with atrial fibrillation also had more laboratory tests (P< .001) and more days receiving cardiac drugs, heparin, diuretics, and electrolytes. Subjects with atrial fibrillation had higher total postoperative charges ($57261 ± $17 101 vs $50905 ± $10062, P= .001), a mean difference of $6356. The mean differences were greatest for bed charges ($1642), laboratory charges ($1215), pharmacy ($989), and respiratory care ($582). Conclusion The economic impact of atrial fibrillation after coronary artery bypass grafting has been underestimated. PMID:12022486
Hald, Erin M; Enga, Kristin F; Løchen, Maja-Lisa; Mathiesen, Ellisiv B; Njølstad, Inger; Wilsgaard, Tom; Braekkan, Sigrid K; Hansen, John-Bjarne
Pulmonary embolism (PE) may trigger atrial fibrillation through increased right atrial pressure and subsequent atrial strain, but the degree of evidence is low. In this study, we wanted to investigate the impact of incident venous thromboembolism (VTE) on future risk of atrial fibrillation in a prospective population-based study. The study included 29 974 subjects recruited from the Tromsø study (1994-1995, 2001-2002, 2007-2008). Incident VTE and atrial fibrillation events were registered from date of enrolment to end of follow-up, December 31, 2010. Cox proportional hazard regression models using age as time-scale and VTE as a time-dependent variable were used to estimate crude and multivariable hazard ratios (HRs) for atrial fibrillation with 95% confidence intervals (CIs). During 16 years of follow up, 540 (1.8%) subjects had an incident VTE event, and 1662 (5.54%) were diagnosed with atrial fibrillation. Among those with VTE, 50 (9.3%) developed subsequent atrial fibrillation. Patients with VTE had 63% higher risk of atrial fibrillation compared to subjects without VTE (multivariable-adjusted HR: 1.63, 95% CI: 1.22 to 2.17). The risk of atrial fibrillation was particularly high during the first 6 months after the VTE event (HR 4.00, 95% CI: 2.21 to 7.25) and among those with PE (HR 1.78, 95% CI: 1.13 to 2.80). We found that incident VTE was associated with future risk of atrial fibrillation. Our findings support the hypothesis that PE may lead to cardiac dysfunctions that, in turn, could trigger atrial fibrillation.
Rho, Robert W; Page, Richard L
Cardioversion of atrial fibrillation (AF) using traditional monophasic shock waveform is unsuccessful in up to 20% of cases, and often requires several shocks of up to 360 J. Based on the success with biphasic shock waveform in converting ventricular fibrillation, it was postulated that biphasic shocks would allow cardioversion with lower energy. In a international multicenter, double-blind, randomized trial of 203 patients, damped sine wave monophasic shocks were compared with impedance-compensated truncated exponential biphasic waveform shocks. Patients received up to five shocks: 100 J, 150 J, 200 J, a fourth shock at maximum output for the initial waveform (200 J biphasic, 360 J monophasic) and a final cross-over shock at maximum output of the alternate waveform. For each energy level, the biphasic waveform compared favorably to the monophasic waveform in successful cardioversion (100 J: 60% versus 22%, P < 0.0001; 150 J: 77% versus 44%, p < 0.0001; 200 J: 90% versus 53%, p < 0.0001). Success with 200 J biphasic was equivalent to 360 J monophasic shock (91% versus 85%, p = 0.29). Patients randomized to biphasic waveform required fewer shocks and lower total energy delivered; in addition, this waveform was associated with less dermal injury and no blistering. Biphasic shocks converted AF present for less than 48 hours with 80% efficacy, but conversion of AF present for more than 48 hours and more than 1 year the success rate was only 63 and 20%, respectively. The results of this study is similar to other investigations comparing biphasic and monophasic shock waveforms for conversion of atrial fibrillation. We recommend starting with biphasic energy of 100 J for atrial fibrillation of less than 48 hours duration, but using higher energies (150 J, 200 J or greater) when AF has been present for longer periods.
Kume, Osamu; Teshima, Yasushi; Abe, Ichitaro; Ikebe, Yuki; Oniki, Takahiro; Kondo, Hidekazu; Saito, Shotaro; Fukui, Akira; Yufu, Kunio; Miura, Masahiro; Shimada, Tatsuo; Takahashi, Naohiko
Monocyte chemoattractant protein-1 (MCP-1)-mediated inflammatory mechanisms have been shown to play a crucial role in atrial fibrosis induced by pressure overload. In the present study, we investigated whether left atrial endothelial cells would quickly respond structurally and functionally to pressure overload to trigger atrial fibrosis and fibrillation. Six-week-old male Sprague-Dawley rats underwent suprarenal abdominal aortic constriction (AAC) or a sham operation. By day 3 after surgery, macrophages were observed to infiltrate into the endocardium. The expression of MCP-1 and E-selectin in atrial endothelium and the expression of intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and ED1 in left atrial tissue were enhanced. Atrial endothelial cells were irregularly hypertrophied with the disarrangement of lines of cells by scanning electron microscopy. Various-sized gap formations appeared along the border in atrial endothelial cells, and several macrophages were located just in the endothelial gap. Along with the development of heterogeneous interstitial fibrosis, interatrial conduction time was prolonged and the inducibility of atrial fibrillation by programmed extrastimuli was increased in the AAC rats compared to the sham-operated rats. Atrial endothelium responds rapidly to pressure overload by expressing adhesion molecules and MCP-1, which induce macrophage infiltration into the atrial tissues. These processes could be an initial step in the development of atrial remodeling for atrial fibrillation. Copyright © 2016 Elsevier Inc. All rights reserved.
Müssigbrodt, A; Weber, A; Mandrola, J; van Belle, Y; Richter, S; Döring, M; Arya, A; Sommer, P; Bollmann, A; Hindricks, G
An interesting and still not well-understood example for old medical wisdom "Sola dosis facit venenum" is the increased prevalence of atrial fibrillation (AF) in athletes. Numerous studies have shown a fourfold to eightfold increased risk of AF in athletes compared to the normal population. Analysis of the existing data suggests a dose-dependent effect of exercise. Moderate exercise seems to have a protective effect and decreases the risk of AF, whereas excessive exercise seems to increase the risk of AF. The described cases illustrate clinical manifestations within the spectrum of AF in elderly athletes, that is, exercise-induced AF, vagal AF, chronic AF, and atrial flutter. As the arrhythmia worsened quality of life and exercise capacity in all patients, recovery of sinus rhythm was desired in all described cases. As the atrial disease was advanced on different levels, different treatment regimes were applied. Lifestyle modification and temporary anti-arrhythmic drug therapy could stabilize sinus rhythm in one patient, whereas others needed radiofrequency ablation to achieve a stable sinus rhythm. The patient with the most advanced atrial disease necessitated anti-arrhythmic drug therapy and another left atrial ablation. All described patients remained in sinus rhythm during the long-term follow-up. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Pandit, Sandeep V.; Workman, Antony J.
Heart failure (HF) causes complex, chronic changes in atrial structure and function, which can cause substantial electrophysiological remodeling and predispose the individual to atrial fibrillation (AF). Pharmacological treatments for preventing AF in patients with HF are limited. Improved understanding of the atrial electrical and ionic/molecular mechanisms that promote AF in these patients could lead to the identification of novel therapeutic targets. Animal models of HF have identified numerous changes in atrial ion currents, intracellular calcium handling, action potential waveform and conduction, as well as expression and signaling of associated proteins. These studies have shown that the pattern of electrophysiological remodeling likely depends on the duration of HF, the underlying cardiac pathology, and the species studied. In atrial myocytes and tissues obtained from patients with HF or left ventricular systolic dysfunction, the data on changes in ion currents and action potentials are largely equivocal, probably owing mainly to difficulties in controlling for the confounding influences of multiple variables, such as patient’s age, sex, disease history, and drug treatments, as well as the technical challenges in obtaining such data. In this review, we provide a summary and comparison of the main animal and human electrophysiological studies to date, with the aim of highlighting the consistencies in some of the remodeling patterns, as well as identifying areas of contention and gaps in the knowledge, which warrant further investigation. PMID:27812293
Altman, Robert K.; Proietti, Riccardo; Barrett, Conor D.; Paoletti Perini, Alessandro; Santangeli, Pasquale; Danik, Stephan B.; Di Biase, Luigi
Over the past two decades, invasive techniques to treat atrial fibrillation (AF) including catheter-based and surgical procedures have evolved along with our understanding of the pathophysiology of this arrhythmia. Surgical treatment of AF may be performed on patients undergoing cardiac surgery for other reasons (concomitant surgical ablation) or as a stand-alone procedure. Advances in technology and technique have made surgical intervention for AF more widespread. Despite improvements in outcome of both catheter-based and surgical treatment for AF, recurrence of atrial arrhythmias following initial invasive therapy may occur.Atrial arrhythmias may occur early or late in the post-operative course after surgical ablation. Early arrhythmias are generally treated with prompt electrical cardioversion with or without antiarrhythmic therapy and do not necessarily represent treatment failure. The mechanism of persistent or late occurring atrial arrhythmias is complex, and these arrhythmias may be resistant to antiarrhythmic drug therapy. The characterization and management of recurrent atrial arrhythmias following surgical ablation of AF are discussed below. PMID:24516805
González Blanco, Virginia; Pérula de Torres, Luis Ángel; Martín Rioboó, Enrique; Martínez Adell, Miguel Ángel; Parras Rejano, Juan Manuel; González Lama, Jesús; Ruiz Moruno, Javier; Martín Alvarez, Remedios; Fernández García, José Ángel; Ruiz de Castroviejo, Joaquin; Roldán Villalobos, Ana; Ruiz Moral, Roger
The goal of this study was to assess the effectiveness of opportunistic screening through pulse palpation in the early detection of atrial fibrillation in subjects aged≥65 years versus detection through an active search for patients with symptoms and/or complications and sequelae associated. This was a cluster randomized controlled trial performed in 48 primary care centers of the Spanish National Healthcare System. A total of 368 physicians and nurses were randomized. The researchers in the experimental group (EG) performed opportunistic screening for auricular fibrillation, whereas the researchers in the control group (CG) actively searched for symptomatic patients. An ECG was performed on patients found to have an irregular heartbeat to confirm the diagnosis of auricular fibrillation. A total of 5,465 patients with a mean age of 75.61 years were recruited for the EG, and 1,525 patients with a mean age of 74.07 years were recruited for the CG. Of these, 58.6% were female, without significant differences between groups. Pulse was irregular in 4.3 and 15.0% of the patients in the EG and the CG, respectively (P<.001). A total of 164 new cases of atrial fibrillation were detected (2.3%), 1.1% in the EG and 6.7% in the CG (adjusted OR: 0.29; 95% CI 0.18-0.45). Case finding for atrial fibrillation in patients aged≥65 years with symptoms or signs suggestive of atrial fibrillation is a more effective strategy than opportunistic screening through pulse palpation in asymptomatic patients. The trial is registered in ClinicalTrials.gov (NCT01291953; February 8, 2011). Copyright © 2016 Elsevier España, S.L.U. All rights reserved.
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.
Enga, K F; Rye-Holmboe, I; Hald, E M; Løchen, M-L; Mathiesen, E B; Njølstad, I; Wilsgaard, T; Braekkan, S K; Hansen, J-B
Whether atrial fibrillation is related to risk of venous thromboembolism (VTE) has not been extensively studied. Therefore, we investigated the association between atrial fibrillation and future risk of VTE in a population-based cohort. In total, 29,975 subjects were recruited from three surveys of the Tromsø study and followed from enrollment (1994-1995, 2001-2002 and 2007-2008) up to 2010. Incident events of atrial fibrillation and VTE during follow-up were recorded. Information on potential confounders was obtained at baseline. Cox-regression models with atrial fibrillation as time-dependent variable were used to calculate hazard ratios (HRs) for VTE with 95% confidence intervals (CIs). During 16 years of median follow-up, 1604 subjects were diagnosed with atrial fibrillation and 614 with incident VTE. The risk of VTE was substantially increased during the first 6 months after diagnosis of atrial fibrillation (HR, 8.44; 95% CI, 5.61-12.69), and remained increased throughout the study period (HR, 1.43; 95% CI, 1.43-1.99) compared with those without atrial fibrillation. Atrial fibrillation displayed higher risk estimates for pulmonary embolism (HR, 11.84; 95% CI, 6.80-20.63) than for deep vein thrombosis (HR, 6.20; 95% CI, 3.37-11.39) during the first 6 months, and was still associated with pulmonary embolism (HR, 1.96; 95% CI, 1.24-3.10) but not with deep vein thrombosis (HR, 1.08; 95% CI, 0.66-1.75) more than 6 months after diagnosis. Atrial fibrillation was associated with increased risk of VTE, and pulmonary embolism in particular. Our findings support the concept that isolated pulmonary embolism may originate from right atrial thrombi due to atrial fibrillation. © 2014 International Society on Thrombosis and Haemostasis.
McCarthy, P M; Castle, L W; Maloney, J D; Trohman, R G; Simmons, T W; White, R D; Klein, A L; Cosgrove, D M
From January 1991 until May 1992, a total of 14 patients (mean age 48 years) underwent the maze procedure for refractory atrial fibrillation (mean duration, 7 years; mean number of antiarrhythmic medications, six). Three patients had had embolic events, one patient had had a cardiac arrest from flecainide, one had pulmonary fibrosis from amiodarone, and six of ten who were employed were temporarily disabled. Two patients underwent successful mitral valve repair in which the maze procedure was added as a secondary goal of the operation. Postoperative fluid retention was a problem in five patients (36%). Six patients (43%) were temporarily treated with an antiarrhythmic medication. Two patients (14%) with preoperative sick sinus syndrome required pacemakers. One patient was discharged from the hospital but died suddenly less than 1 month after the operation (7% operative mortality) of hyperkalemia caused by acute renal failure. All patients beyond 3 postoperative months (100% "cure") are receiving no antiarrhythmic medications, have sinus rhythm, or have p-wave tracking with ventricular pacing. Atrial contraction has been documented by cinegraphic magnetic resonance imaging studies and by Doppler echocardiography performed when sinus rhythm had resumed. The maze procedure is an extensive operation but is indicated for selected patients who have the severe sequelae of atrial fibrillation.
Hu, Xiaoliang; Jiang, Jingzhou; Ma, Yuedong; Tang, Anli
Background Circumferential pulmonary vein isolation (CPVI) is a widely used treatment for paroxysmal atrial fibrillation (AF). Several P wave duration (PWD) parameters have been suggested to predict post-ablation recurrence, but their use remains controversial. This study aimed to identify novel P wave indices that predict post-ablation AF recurrence. Material/Methods We selected 171 consecutive patients undergoing CPVI for paroxysmal AF. Electrocardiography (ECG) recordings were obtained at the beginning and the end of ablation. PWD was measured in all 12 leads. The PWD variation was calculated by subtracting the pre-ablation PWD from the post-ablation PWD. Results PWD was significantly shortened in leads II, III, aVF, and V1 after ablation. During a mean follow-up of 19.96±4.32 months, AF recurrence occurred in 32 (18.7%) patients. No significant differences in baseline characteristics or pre- or post-ablation PWD were observed between the AF recurrence and non-recurrence groups. Patients with AF recurrence exhibited a smaller PWD variation in leads II (1.21(−0.56, 2.40) vs. −5.77(−9.10, −4.06) ms, P<0.001), III (−5.92(−9.87, 3.27) vs. −9.44(−11.89, −5.57) ms, P=0.001) and V1 (−4.43(−6.64, −3.13) vs. −6.33(−8.19,−4.59) ms, P=0.003). Multivariable logistic regression analysis demonstrated that smaller PWD variations in lead II and III were independent risk factors for AF recurrence. PWD variation ≥−2.21 ms in lead II displayed the highest combined sensitivity and specificity (85.29% and 83.94%, respectively) for predicting post-ablation AF recurrence. A PWD variation ≥0 ms displayed the best practical value in predicting AF recurrence. Conclusions PWD variation in lead II is an effective predictor of post-ablation AF recurrence. PMID:27450644
Lubitz, Steven A.; Yin, Xiaoyan; Fontes, João D.; Magnani, Jared W.; Rienstra, Michiel; Pai, Manju; Villalon, Mark L.; Vasan, Ramachandran S.; Pencina, Michael J.; Levy, Daniel; Larson, Martin G.; Ellinor, Patrick T.; Benjamin, Emelia J.
Context Although the heritability of atrial fibrillation (AF) is established, the contribution of familial AF to predicting new-onset AF remains unknown. Objective To determine whether familial occurrence of AF is associated with new-onset AF beyond established risk factors. Design, Setting, and Participants The Framingham Heart Study, a prospective population-based cohort study started in 1948. Original and Offspring Cohort participants were age at least 30 years, free of AF at the baseline examination, and had at least one parent or sibling enrolled in the study. Main outcome measures The incremental predictive value of incorporating different features of familial AF (any familial AF, premature familial AF [onset ≤65 years], number of affected relatives, and youngest age of onset in a relative) into a risk model for new-onset AF. Results Of 4421 participants (11971 person-examinations, mean age 54±13 years, 54% women), 440 developed AF during follow-up. Familial AF occurred in 1185 participants (26.8%) and premature familial AF occurred in 351 (7.9%) participants. AF occurred more frequently among participants with familial AF than without familial AF (unadjusted absolute event rates of 5.8% and 3.1%, respectively). The association was not attenuated by adjustment for AF risk factors (multivariable-adjusted HR 1.40, 95% CI 1.13–1.74) or reported AF-related genetic variants. Among the different features of familial AF examined, premature familial AF was associated with improved discrimination beyond traditional risk factors to the greatest extent (c-statistic 0.842; 95% CI, 0.826–0.858 to 0.846; 95%CI, 0.831–0.862; P=.004). Modest changes in integrated discrimination improvement were observed with premature familial AF (2.1%). Net reclassification improvement (assessed using eight-year risk thresholds of <5%, 5–10%, >10%) did not change significantly with premature familial AF (0.011; 95% CI, −0.021–0.042; P=.51), although category-less net
Mazurek, Michał; Shantsila, Eduard; Lane, Deirdre A; Wolff, Andreas; Proietti, Marco; Lip, Gregory Y H
Although patients with atrial fibrillation (AF) who experienced an acute stroke are at high risk for recurrence, many patients are untreated or treated suboptimally for stroke prevention. The objective of this study is to compare clinical outcomes of AF patients with versus without previous stroke in relation to guideline-adherent antithrombotic treatment in a contemporary primary care population. Community cohort of 105 000 patients from 11 general practices in Darlington, England, was used to assess AF stroke prevention strategies against 2014 National Institute for Health and Care Excellence guidelines. Overall, 2259 (2.15%) patients with AF were identified, of which 18.9% constituted a secondary prevention cohort. For secondary prevention, antithrombotic treatment was guideline adherent in 56.3%, 18.9% were overtreated, and 24.8% undertreated; corresponding proportions for primary prevention were 49.5%, 11.7%, and 38.8%, respectively. One-year stroke rates were 8.6% and 1.6% for secondary and primary prevention, respectively (P<0.001); corresponding all-cause mortality rates were 9.8% and 9.4%, respectively (P=0.79). On multivariable analysis, lack of antithrombotic treatment guideline adherence was associated with increased stroke risk for primary prevention (odds ratio, 2.95; 95% confidence interval, 1.26-6.90; P=0.013 for undertreatment); for secondary prevention, lack of guideline adherence was associated with increased risk of recurrent stroke (odds ratio, 2.80; 95% confidence interval, 1.25-6.27; P=0.012 for overtreatment) and all-cause death (odds ratio, 2.75; 95% confidence interval, 1.33-5.69; P=0.006 for undertreatment). Only approximately half of eligible patients with AF are prescribed oral anticoagulation in line with guidelines. Guideline-adherent antithrombotic treatment significantly reduces the risk of stroke among primary prevention patients and both risk of recurrent stroke and death in patients with previous stroke. © 2017 American Heart
Lee, Hsiu-Hao; Chen, Yueh-Chung; Chen, Jien-Jiun; Lo, Shih-Hsiang; Guo, Yue-Liang; Hu, Hsiao-Yun
Background Although advancements in the treatment of atrial fibrillation have improved patient prognosis for this persistent condition, interest in atrial fibrillation development is growing. Of note is the fact that additional attention is being focused on the accompanying effect of insomnia. The aim of the study was to investigate the effects of insomnia on the risk of atrial fibrillation development. Methods This was a nationwide population-based retrospective cohort study using data from the Taiwan National health Insurance Research Database. We analyzed 64,421 insomnia cases and 128,842 matched controls without insomnia from January 1, 2000, to December 31, 2010. A Cox regression model was used to estimate the adjusted hazard ratios (HRs) and 95% confidence intervals (CI) for atrial fibrillation development. Results During the follow-up period, the incidence of atrial fibrillation development was significantly higher in the insomnia cases than in the comparison cohort (2.6% vs. 2.3%, p < 0.001). Insomnia was associated with an increased risk of atrial fibrillation (HR = 1.08, 95% CI: 1.01-1.14). Males, those > 65 years of age, and patients with peripheral artery disease who have insomnia had a higher rate of atrial fibrillation development. Conclusions The findings of this nationwide analysis support the hypothesis that insomnia is associated with a significant risk of atrial fibrillation development. PMID:28344420
Kohno, Hiroki; Ueda, Hideki; Matsuura, Kaoru; Tamura, Yusaku; Watanabe, Michiko; Matsumiya, Goro
Background Atrial fibrillation is a common complication after cardiac surgery, but the risk factors and long-term outcome after primary isolated aortic valve replacement remains to be clarified. Methods A single-center retrospective study was conducted on 157 patients who underwent first-time isolated aortic valve replacement between April 1999 and February 2015. Fifty-eight patients developed new-onset atrial fibrillation within 6 months postoperatively, and they were compared with patients who remained in sinus rhythm. Multivariate analyses, which incorporated the propensity score patient matching technique, were conducted to evaluate the long-term outcome of new-onset postoperative atrial fibrillation and identify patients at risk of developing this arrhythmia. Results At a mean follow-up of 52.4 months (range 8.4-200.7 months), mortality was significantly higher in patients who developed atrial fibrillation compared to those who remained in sinus rhythm (2.8%/patient-year vs. 0.2%/patient-year, respectively; p < 0.05). Patients developing atrial fibrillation were also at an independently increased risk of stroke and readmission during follow-up. Risk analysis revealed that advanced age (>70 years) and absence of a postoperative β-blocker were predictors of atrial fibrillation. Conclusions New-onset atrial fibrillation after first-time isolated aortic valve replacement correlated significantly with late morbidity and mortality. Advanced age and absence of a postoperative β-blocker may increase the incidence of atrial fibrillation.
Tamargo Menéndez, Juan
Atrial fibrillation starts in the left atrium and from there the activity invades the atrial tissues and causes an inhomogeneous shortening the duration of atrial action potential duration and refractoriness. The purpose of this study was to compare the voltage-dependent potassium currents in human cells isolated from the right and left atria and to determine whether electrical remodeling produced by chronic atrial fibrillation (CAF) differentially affects voltage-dependent potassium currents involved in atrial repolarization in each atrium as compared to sinus rhythm (SR). The currents were recorded using the whole-cell configuration of the patch-clamp technique. We found that in atrial cardiomyocytes of patients both in SR and in CAF there are three types of cells according to their main voltage-dependent repolarizing potassium current: the Ca(2+)-independent 4-aminopyridine sensitive component of the transient outward current (I(to1)) and the ultrarapid (I(Kur)), rapid (I(Kr)) and slow (I(Ks)) components of the delayed rectifier current. CAF differentially modified the proportion of these 3 types of cells on each atrium: CAF reduced the I(to1) more markedly in the left than in the right atria, while I(Kur) was more markedly reduced in the right than in the left atria. Interestingly, in both atria, CAF markedly increased the I(Ks). This increase was enhanced by isoproterenol and suppressed by atenolol. These changes produce a non-uniform shortening of atrial repolarization that facilitates the reentry of the cardiac impulse and the perpetuation of the arrhythmia.
Mont, Lluís; Elosua, Roberto; Brugada, Josep
Although the benefits of regular exercise in controlling cardiovascular risk factors have been extensively proven, little is known about the long-term cardiovascular effects of regular and extreme endurance sport practice, such as jogging, cycling, rowing, swimming, etc. Recent data from a small series suggest a relationship between regular, long-term endurance sport practice and atrial fibrillation (AF) and flutter. Reported case control studies included less than 300 athletes, with mean age between 40 and 50. Most series recruited only male patients, or more than 70% males, who had been involved in intense training for many years. Endurance sport practice increases between 2 and 10 times the probability of suffering AF, after adjusting for other risk factors. The possible mechanisms explaining the association remain speculative. Atrial ectopic beats, inflammatory changes, and atrial size have been suggested. Some of the published studies found that atrial size was larger in athletes than in controls, and this was a predictor for AF. It has also been shown that the left atrium may be enlarged in as many as 20% of competitive athletes. Other proposed mechanisms are increased vagal tone and bradycardia, affecting the atrial refractory period; however, this may facilitate rather than cause the arrhythmia. In summary, recent data suggest an association between endurance sport practice and atrial fibrillation and flutter. The underlying mechanism explaining this association is unclear, although structural atrial changes (dilatation and fibrosis) are probably present. Larger longitudinal studies and mechanistic studies are needed to further characterize the association to clarify whether a threshold limit for the intensity and duration of physical activity may prevent AF, without limiting the cardiovascular benefits of exercise.
D'Ascenzi, Flavio; Cameli, Matteo; Ciccone, Marco M; Maiello, Maria; Modesti, Pietro A; Mondillo, Sergio; Muiesan, Maria L; Scicchitano, Pietro; Novo, Salvatore; Palmiero, Pasquale; Saba, Pier S; Pedrinelli, Roberto
Atrial fibrillation is the most common clinically significant arrhythmia observed both in the general population and in competitive athletes. The most important risk factors are all preventable by regular physical activity. However, although the benefits of moderate physical activity in controlling cardiovascular risk factors and decreasing the risk of atrial fibrillation have been extensively proved, concerns have arisen about the potential negative effects of vigorous exercise, particularly in endurance athletes. Furthermore, in a subset of patients with atrial fibrillation younger than 60 years, routine evaluation does not reveal any cardiovascular disease or any other known causal factor. This condition is called 'lone atrial fibrillation', and the potential mechanisms underlying this condition are speculative and remain to be clarified. Atrial ectopy, increased vagal tone, changes in electrolytes, left atrial dilatation, and fibrosis have been proposed among others as potential mechanisms. However, no convincing data still exist. Particularly, the increase in left atrial size represents in athletes a physiological adaptation to exercise conditioning and the presence of biatrial fibrosis has not been demonstrated in humans. Thus, contrary to patients with cardiovascular disorders, the atrial substrate seems to play a secondary role in healthy athletes. This review article analyzes the controversial relationship between atrial fibrillation and physical activity, with a particular attention on the pathophysiological mechanisms that could be responsible for atrial fibrillation in the athletic population.
Käräjämäki, Aki Juhani; Kettunen, Olli; Lepojärvi, Samuli; Koivurova, Olli-Pekka; Kesäniemi, Y. Antero; Huikuri, Heikki; Ukkola, Olavi
Background Chronic liver injury from different etiologies drives liver fibrosis. However, little is known about the associated factors, systemic factors in particular. Recently, non-alcoholic fatty liver disease (NAFLD) and atrial fibrillation have been shown to be associated with each other. Thereby, we aimed to study the association between atrial fibrillation and liver stiffness. Study Extensive clinical measurements including echocardiography of the heart, transient elastography (TE) of the liver and the presence of atrial fibrillation were determined in elderly Finnish study subjects (n = 76, mean age 73 years) from OPERA (Oulu Project Elucidating the Risk of Atherosclerosis) study cohort. Half of the study subjects had non-alcoholic fatty liver disease, whereas others did not have any known hepatic morbidity. The present study was cross-sectional by nature. Results The subjects with atrial fibrillation had higher TE values (with atrial fibrillation TE = 9.3kPa, without atrial fibrillation TE = 6.3kPa, p = 0.018). When the cohort was divided to four subgroups (those without NAFLD or atrial fibrillation, with NAFLD but without atrial fibrillation, with both conditions, and with atrial fibrillation but without NAFLD), the TE value was the highest in the subjects with both conditions (5.3kPa, 7.4kPa, 10.8kPa and 7.8kPa, respectively, p = 0.019). Moreover, the higher the TE value, the more prevalent atrial fibrillation was (the atrial fibrillation prevalence by tertiles of TE 27% / 36% / 77%, p = 0.001). Likewise, the greater the TE value, the greater the left atrial diameter, a collateral of atrial fibrillation (left atrial diameters by tertiles of TE 39mm / 45mm / 48mm, p<0.001) was. All these p-values for continuous variables remained statistically significant even after adjustment for common clinically relevant risk factors. Conclusions There is an association between atrial fibrillation and liver stiffness. This novel association may have multiple
Ellinor, Patrick T; Lunetta, Kathryn L; Albert, Christine M; Glazer, Nicole L; Ritchie, Marylyn D; Smith, Albert V; Arking, Dan E; Müller-Nurasyid, Martina; Krijthe, Bouwe P; Lubitz, Steven A; Bis, Joshua C; Chung, Mina K; Dörr, Marcus; Ozaki, Kouichi; Roberts, Jason D; Smith, J Gustav; Pfeufer, Arne; Sinner, Moritz F; Lohman, Kurt; Ding, Jingzhong; Smith, Nicholas L; Smith, Jonathan D; Rienstra, Michiel; Rice, Kenneth M; Van Wagoner, David R; Magnani, Jared W; Wakili, Reza; Clauss, Sebastian; Rotter, Jerome I; Steinbeck, Gerhard; Launer, Lenore J; Davies, Robert W; Borkovich, Matthew; Harris, Tamara B; Lin, Honghuang; Völker, Uwe; Völzke, Henry; Milan, David J; Hofman, Albert; Boerwinkle, Eric; Chen, Lin Y; Soliman, Elsayed Z; Voight, Benjamin F; Li, Guo; Chakravarti, Aravinda; Kubo, Michiaki; Tedrow, Usha B; Rose, Lynda M; Ridker, Paul M; Conen, David; Tsunoda, Tatsuhiko; Furukawa, Tetsushi; Sotoodehnia, Nona; Xu, Siyan; Kamatani, Naoyuki; Levy, Daniel; Nakamura, Yusuke; Parvez, Babar; Mahida, Saagar; Furie, Karen L; Rosand, Jonathan; Muhammad, Raafia; Psaty, Bruce M; Meitinger, Thomas; Perz, Siegfried; Wichmann, H-Erich; Witteman, Jacqueline C M; Kao, W H Linda; Kathiresan, Sekar; Roden, Dan M; Uitterlinden, Andre G; Rivadeneira, Fernando; McKnight, Barbara; Sjögren, Marketa; Newman, Anne B; Liu, Yongmei; Gollob, Michael H; Melander, Olle; Tanaka, Toshihiro; Ch Stricker, Bruno H; Felix, Stephan B; Alonso, Alvaro; Darbar, Dawood; Barnard, John; Chasman, Daniel I; Heckbert, Susan R; Benjamin, Emelia J; Gudnason, Vilmundur; Kääb, Stefan
Atrial fibrillation is a highly prevalent arrhythmia and a major risk factor for stroke, heart failure and death1. We conducted a genome-wide association study (GWAS) in individuals of European ancestry, including 6,707 with and 52,426 without atrial fibrillation. Six new atrial fibrillation susceptibility loci were identified and replicated in an additional sample of individuals of European ancestry, including 5,381 subjects with and 1 0,030 subjects without atrial fibrillation (P < 5 × 10−8). Four of the loci identified in Europeans were further replicated in silico in a GWAS of Japanese individuals, including 843 individuals with and 3,350 individuals without atrial fibrillation. The identified loci implicate candidate genes that encode transcription factors related to cardiopulmonary development, cardiac-expressed ion channels and cell signaling molecules. PMID:22544366
Bilotta, F; Pizzichetta, F; Fiorani, L; Paoloni, F P; Delfini, R; Rosa, G
The aim of this prospective study was to determine the prevalence of pre-operative atrial fibrillation and the incidence of postoperative atrial fibrillation in patients undergoing elective or emergency intracranial neurosurgical procedures and the relation to survival and neurological outcome at 6-months follow-up compared to patients with sinus rhythm. A total of 2020 patients were enrolled; 1540 patients underwent elective procedures and 480 underwent emergency procedures. Prevalence of pre-operative atrial fibrillation was 3.7% in elective and 7.2% in emergency procedures (p = 0.0012). In patients undergoing elective cerebral procedures with pre-operative atrial fibrillation, compared to patients with sinus rhythm, 6-month neurological outcome and survival rate are similar. In patients undergoing emergency neurosurgical cerebral procedures, the presence of pre-operative atrial fibrillation is related to an increased risk of poor neurological outcome but with similar survival rate.
de Figueiredo, Marcelo Marinho; Rodrigues, Ana Clara Tude; Alves, Monique Bueno; Neto, Miguel Cendoroglo; Silva, Gisele Sampaio
OBJECTIVE: Atrial fibrillation is a common arrhythmia that increases the risk of stroke by four- to five-fold. We aimed to establish a profile of patients with atrial fibrillation from a population of patients admitted with acute ischemic stroke or transient ischemic attack using clinical and echocardiographic findings. METHODS: We evaluated patients consecutively admitted to a tertiary hospital with acute ischemic stroke or transient ischemic attack. Subjects were divided into an original set (admissions from May 2009 to October 2010) and a validation set (admissions from November 2010 to April 2013). The study was designed as a cohort, with clinical and echocardiographic findings compared between patients with and without atrial fibrillation. A multivariable model was built, and independent predictive factors were used to produce a predictive grading score for atrial fibrillation (Acute Stroke AF Score-ASAS). RESULTS: A total of 257 patients were evaluated from May 2009 to October 2010 and included in the original set. Atrial fibrillation was diagnosed in 17.5% of these patients. Significant predictors of atrial fibrillation in the multivariate analysis included age, National Institutes of Health Stroke Scores, and the presence of left atrial enlargement. These predictors were used in the final logistic model. For this model, the area under the receiver operating characteristic curve was 0.79. The score derived from the logistic regression analysis was The model developed from the original data set was then applied to the validation data set, showing the preserved discriminatory ability of the model (c statistic = 0.76). CONCLUSIONS: Our risk score suggests that the individual risk for atrial fibrillation in patients with acute ischemic stroke can be assessed using simple data, including age, National Institutes of Health Stroke Scores at admission, and the presence of left atrial enlargement. PMID:24714831
Bosomworth, N John
To review the evidence on the effects of various levels of physical activity (PA) on the incidence of atrial fibrillation (AF) in both the general population and in endurance athletes. A PubMed search was done initially using the MeSH headings or text words (with the search-field descriptor TIAB [title and abstract]) atrial fibrillation and exercise or physical activity or athlet* or sport*, without additional filters. Conclusions regarding quality and strength of evidence were based on the GRADE (grading of recommendations, assessment, development, and evaluation) system. No interventional studies were available. Observational studies were therefore considered acceptable, and, although larger long-term prospective cohort studies were preferred, case-control or cross-sectional trials were also included in this review. Available evidence suggests a dose-response association linking increased exercise levels with reduced incident AF in women. The same is true in men at low and moderate levels of exertional activity. In men only, high levels of PA are associated with increased risk of AF in most, but not all, studies. This risk is moderate, with a hazard ratio of 1.29 in one of the better studies. The risk of AF for most people who exercise regularly is lower than that of a matched sedentary population. Atrial fibrillation is probably less common as PA increases, with a demonstrable dose-response relationship. Exercise at any level should be promoted for its effect on physical well-being and mortality reduction. In men exercising at high levels, beneficial effects on AF might be lost and risk might exceed that of the sedentary population; however, the evidence is neither robust nor consistent. These men should be made aware of this modest increase in risk should they choose to continue to engage in high levels of PA. Copyright© the College of Family Physicians of Canada.
Pazianas, Michael; Cooper, Cyrus; Wang, Yiting; Lange, Jeff L; Russell, R Graham G
Background: Epidemiological studies investigating a possible association between bisphosphonates and atrial fibrillation (AF) have reported conflicting findings. The objective of our study was to determine whether exposure to oral nitrogen-containing bisphosphonates alendronate and risedronate are associated with increased incidence of atrial fibrillation. Methods: In a retrospective cohort study we analyzed data from three large independent databases, two from the United States (MarketScan® and Ingenix®) and one from the United Kingdom (THIN). 144,548 women, age 50–89, bisphosphonate users during 2002–2005 were compared to 668,891 sex- and age-matched controls (1:4). Our primary outcome measure was new incident atrial fibrillation for up to three years; Cox models adjusted for disease and drug history were used to estimated relative risks. Results: We identified a total of 8,001, 1,984, and 817 AF cases in oral bisphosphonate users and nonusers during 744,340 (MarketScan), 243,898 (Ingenix), and 148,779 (THIN) person-years of follow-up, respectively. Compared to nonusers, overall adjusted relative risk (adjRR) (95% confidence interval [CI]) for AF in oral bisphosphonates users was 0.92 (0.85–0.99; MarketScan), 1.00 (0.87–1.16; Ingenix), and 0.97 (0.79–1.20; THIN); overall adjRR (95% CI) for any cardiac dysrrhythmia for MarketScan was 1.01 (0.98–1.05), Ingenix 1.06 (0.99–1.13), and THIN 0.97 (0.79–1.20). Conclusions: In all three databases from the two countries, the risk of AF or cardiac dysrrhythmia was not increased in postmenopausal women treated for up to three years with oral alendronate or risedronate. PMID:21479144
Chao, Tze-Fan; Liu, Chia-Jen; Tuan, Ta-Chuan; Chen, Su-Jung; Wang, Kang-Ling; Lin, Yenn-Jiang; Chang, Shih-Lin; Lo, Li-Wei; Hu, Yu-Feng; Chen, Tzeng-Ji; Chiang, Chern-En; Chen, Shih-Ann
Current American and European guidelines emphasize the importance of rate-control treatments in treating atrial fibrillation with a Class I recommendation, although data on the survival benefits of rate control are lacking. The goal of the present study was to investigate whether patients receiving rate-control drugs had a better prognosis compared with those without rate-control treatment. This study used the National Health Insurance Research Database in Taiwan. There were 43 879, 18 466, and 38 898 patients with atrial fibrillation enrolled in the groups receiving β-blockers, calcium channel blockers, and digoxin, respectively. The reference group consisted of 168 678 subjects who did not receive any rate-control drug. The clinical end point was all-cause mortality. During a follow-up of 4.9±3.7 years, mortality occurred in 88 263 patients (32.7%). After adjustment for baseline differences, the risk of mortality was lower in patients receiving β-blockers (adjusted hazard ratio=0.76; 95% confidence interval=0.74-0.78) and calcium channel blockers (adjusted hazard ratio=0.93; 95% confidence interval=0.90-0.96) compared with those who did not receive rate-control medications. On the contrary, the digoxin group had a higher risk of mortality with an adjusted hazard ratio of 1.12 (95% confidence interval=1.10-1.14). The results were observed consistently in subgroup analyses and among the cohorts after propensity matching. In this nationwide atrial fibrillation cohort, the risk of mortality was lower for patients receiving rate-control treatment with β-blockers or calcium channel blockers, and the use of β-blockers was associated with the largest risk reduction. Digoxin use was associated with greater mortality. Prospective, randomized trials are necessary to confirm these findings. © 2015 American Heart Association, Inc.
Synopsis Atrial fibrillation (AF) is a complex arrhythmia with multiple possible mechanisms. It requires a trigger for initiation and a favorable substrate for maintenance. Pulmonary vein myocardial sleeves have the potential to generate spontaneous activity, and such arrhythmogenic activity is surfaced by modulation of intracellular calcium dynamics. Direct autonomic nerve recordings in canine models demonstrate that simultaneous sympathovagal discharges are the most common triggers of paroxysmal atrial tachycardia and paroxysmal AF. Autonomic modulation as a potential therapeutic strategy has been targeted clinically and experimentally, but its effectiveness as an adjunctive therapeutic modality to catheter ablation of AF has been inconsistent. Further studies are warranted before application can be widely implied for therapies of clinical AF. PMID:19111762
Ogunsua, Adedotun A; Shaikh, Amir Y; Ahmed, Mohamed; McManus, David D
Atrial fibrillation (AF) is an increasingly prevalent condition and the most common sustained arrhythmia encountered in ambulatory and hospital practice. Several clinical risk factors for AF include age, sex, valvular heart disease, obesity, sleep apnea, heart failure, and hypertension (HTN). Of all the risk factors, HTN is the most commonly encountered condition in patients with incident AF. Hypertension is associated with a 1.8-fold increase in the risk of developing new-onset AF and a 1.5-fold increase in the risk of progression to permanent AF. Hypertension predisposes to cardiac structural changes that influence the development of AF such as atrial remodeling. The renin angiotensin aldosterone system has been demonstrated to be a common mechanistic link in the pathogenesis of HTN and AF. Importantly, HTN is one of the few modifiable AF risk factors, and guideline-directed management of HTN may reduce the incidence of AF.
Duytschaever, Mattias; Danse, Peter; Allessie, Maurits
Recent studies with the implantable atrial cardioverter have shown that atrial fibrillation (AF) recurs almost immediately after successful cardioversion in about 27% of cases. In the present study, we determined the electrophysiologic properties of the caprine atrium immediately after spontaneous termination of AF both before and after 48 hours of AF-induced electrical remodeling. In eight goats, atrial effective refractory period (AERP), intra-atrial conduction velocity, and atrial wavelength were measured during sinus rhythm both before (t = 0) and after 48 hours (t = 48) of electrically maintained AF (baseline). After baseline, a 5-minute paroxysm of AF was induced, during which the refractory period (RPAF) was determined. AERP, conduction velocity, and atrial wavelength also were measured immediately after spontaneous restoration of sinus rhythm (post-AF values). Both in normal and remodeled atria, immediately after AF, AERP and conduction velocity were markedly decreased compared with baseline (P < 0.01). In normal atria, post-AF AERP (107+/-14 msec) gradually prolonged from its AF value (114+/-17 msec) to its baseline value (138+/-13 msec). Conduction velocity decreased from 130+/-9 cm/sec to 117+/-9 cm/sec. After 48 hours of AF, AERP had shortened to 74+/-8 msec. RPAF was 89+/-9 msec. Surprisingly, immediately after termination of AF, AERP shortened further to 58+/-6 msec (P < 0.01). Post-AF conduction velocity decreased from 136+/-11 cm/sec to 122+/-10 cm/sec (P < 0.01). As a result, the post-AF atrial wavelength became as short as 7.1+/-1 cm. These changes were transient, and all parameters gradually returned to baseline within 1 to 2 minutes after conversion of AF. Due to a combined decrease in AERP and conduction velocity, marked shortening of the atrial wavelength occurs during the first minutes after conversion of AF. In electrically remodeled atria, this results in a transient ultrashort value of AERP (<60 msec) and atrial wavelength (7.1 cm). These
Myrstad, Marius; Nystad, Wenche; Graff-Iversen, Sidsel; Thelle, Dag S; Stigum, Hein; Aarønæs, Marit; Ranhoff, Anette H
Emerging evidence suggests that endurance exercise increases the risk for atrial fibrillation (AF) in men, but few studies have investigated the dose-response relation between exercise and risk for atrial arrhythmias. Both exposure to exercise and reference points vary among studies, and previous studies have not differentiated between AF and atrial flutter. The aim of this study was to assess the risk for atrial arrhythmias by cumulative years of regular endurance exercise in men. To cover the range from physical inactivity to long-term endurance exercise, the study sample in this retrospective cohort study was based on 2 distinct cohorts: male participants in a long-distance cross-country ski race and men from the general population, in total 3,545 men aged ≥ 53 years. Arrhythmia diagnoses were validated by electrocardiograms during review of medical records. Regular endurance exercise was self-reported by questionnaire. A broad range of confounding factors was available for adjustment. The adjusted odds ratios per 10 years of regular endurance exercise were 1.16 (95% confidence interval 1.06 to 1.29) for AF and 1.42 (95% confidence interval 1.20 to 1.69) for atrial flutter. In stratified analyses, the associations were significant in cross-country skiers and in men from the general population. In conclusion, cumulative years of regular endurance exercise were associated with a gradually increased risk for AF and atrial flutter. Copyright © 2014 Elsevier Inc. All rights reserved.
Xie, Jun; Chen, Yuhan; Hu, Chuanxian; Pan, Quanhua; Wang, Bingjian; Li, Xueling; Geng, Jin; Xu, Biao
Premature senescence is associated with atrial fibrosis and has an antifibrotic effect in mice. However, the role of senescence in atrial fibrillation (AF) remains unclear. Here, we investigated the association of premature senescence with fibrosis and also determined the role of senescence in the recurrence of AF after surgery ablation. Western blot, Sirius red staining, SA-β-gal staining and immunohistochemistry were performed to detect the degree of atrial fibrosis ,the expression of TGF-β and collagens, and also the senescence markers in 72 tissue specimens of left atrial appendage in this study. Then the patients undergoing successful surgical ablation were followed up for 12 months. The expression of collagens and TGF-β was paralleled by a high level of atrial fibrosis and were increased in AF group, especially in the persistent AF group. Western blotting of P16 and SA-β-gal staining showed an increased premature senescence in the sinus rhythm, paroxysmal AF and persistent AF groups. In addition, positive area of senescence markers, SA-β-gal and P16, was correlated positively with fibrotic lesions. We also found a lower ratio of P16/TGF-β in patients with recurrence of AF than in patients without recurrent AF. In conclusion, premature senescence is associated with atrial fibrosis in AF, and may have an antifibrotic role in AF.
Stähli, Barbara E; Gebhard, Cathérine; Gick, Michael; Mashayekhi, Kambis; Ferenc, Miroslaw; Buettner, Heinz Joachim; Neumann, Franz-Josef; Toma, Aurel
Successful CTO recanalization has been associated with clinical benefit. Outcomes of patients with atrial fibrillation undergoing CTO PCI have not been investigated, yet. This study sought to evaluate the association between atrial fibrillation and outcomes after percutaneous coronary intervention (PCI) for chronic total occlusions (CTO). Consecutive patients undergoing CTO PCI between January 2005 and December 2013 were divided into patients with and without atrial fibrillation, and propensity-matched models used to adjust for baseline differences between groups. The primary outcome was all-cause mortality at a median follow-up of 3.2 (interquartile range 3.1-4.5) years. Of 2002 patients undergoing CTO PCI, atrial fibrillation was present in 169 (8.4%) patients. Patients with atrial fibrillation were older, and more frequently had hypertension, left ventricular systolic dysfunction, and chronic kidney disease. Before matching, all-cause mortality was 39.6 and 14.5% in the atrial fibrillation and the sinus rhythm groups (HR 2.92, 95% CI 2.23-3.82, p < 0.001). In the propensity-matched model, atrial fibrillation remained associated with an increased risk of mortality (HR 1.62, 95% CI 1.06-2.47, p = 0.03). In the unmatched patient cohort, all-cause mortality was significantly reduced in patients with procedural success, both in the atrial fibrillation (34.9 versus 55.0%, adjusted HR 0.99, 95% CI 0.97-1.00, p = 0.02) and the sinus rhythm groups (12.8 versus 23.0%, adjusted HR 0.70, 95% CI 0.53-0.92, p = 0.01). Although atrial fibrillation is independently associated with mortality after CTO PCI, substantial survival benefit of successful CTO recanalization is observed in both patients with and without atrial fibrillation.
Ren, W D; Visentin, P; Nicolosi, G L; Canterin, F A; Dall'Aglio, V; Lestuzzi, C; Mimo, R; Pavan, D; Sparacino, L; Cervesato, E
The effect of atrial fibrillation on pulmonary venous flow patterns is still not well known. Twenty-four patients in atrial fibrillation and 21 patients in sinus rhythm were studied by transoesophageal echocardiography. In ninety-five percent (20/21) of sinus rhythm patients, the early systolic wave due to atrial relaxation or reverse wave due to atrial contraction could be distinguished on pulsed Doppler tracings by transoesophageal echocardiography. However, there was no early systolic wave and/or reverse at the end of diastole in any atrial fibrillation patients. In atrial fibrillation patients without mitral regurgitation (n = 14), the onset of systolic flow was delayed (165 +/- 38 vs 50 +/- 46 ms, P < 0.05), and systolic peak velocities, time-velocity integrals and systolic fractions were reduced (31 +/- 13 vs 54 +/- 17 cm.s-1, P < 0.05; 5 +/- 2 vs 13 +/- 6 cm, P < 0.05 and 36 +/- 8 vs 61 +/- 15%, P < 0.05, respectively) as compared to those in sinus rhythm. Significant mitral regurgitation (n = 10) reduced systolic velocity parameters considerably in atrial fibrillation patients but the diastolic flow parameters were not significantly different between sinus rhythm and atrial fibrillation patients. Stepwise multiple regression analysis identified atrial fibrillation as an important independent predictor for changes in systolic flow parameters. The R-R interval is also an important factor for diastolic flow parameters. Thus, the present study demonstrates that atrial fibrillation significantly modifies pulmonary venous flow pattern and is an important factor for systolic flow parameters. Significant mitral regurgitation can further modify systolic flow pattern in atrial fibrillation patients.
Melby, Spencer J.; Schuessler, Richard B.; Damiano, Ralph J.
The Cox maze procedure for the surgical treatment of atrial fibrillation has been simplified from its original cut-and-sew technique. Various energy sources now exist which create linear lines of ablation that can be used to replace the original incisions, greatly facilitating the surgical approach. This review article describes the anatomy of the atria that must be considered in choosing a successful energy source. Furthermore the device characteristics, safety profile, mechanism of tissue injury, and ability to create transmural lesions of the various energy sources that have been used in the Cox maze procedure, along with the strengths and weaknesses of each device is discussed. PMID:23995989
da Silva, Ananília Medeiros Gomes; de Araújo, Jéssica Nayara Góes; de Freitas, Renata Caroline Costa
Atrial fibrillation (AF) is the most common supraventricular arrhythmia in the population. MicroRNAs (small endogenous noncoding RNAs) are attractive candidates as biomarkers for AF, especially considering that miRNAs are stable and are detected within easily accessible biofluids such as blood. In this review, we selected twelve studies (2012 to 2016) that were classified according to the sample type. We aimed to provide an overview of the role of circulating miRNAs in AF and to discuss the variability of the results, seeking to improve the perspective of the use of miRNAs as potential noninvasive biomarkers for this heart disease. PMID:28349066
Yang, Felix; Chou, Denise; Schweitzer, Paul; Hanon, Sam
Warfarin is commonly used to prevent stroke in patients with atrial fibrillation; however, patients on haemodialysis may not derive the same benefit from warfarin as the general population. There are no randomized controlled studies in dialysis patients which demonstrate the efficacy of warfarin in preventing stroke. In fact, warfarin places the dialysis patient at increased risk for haemorrhagic stroke and possibly ischaemic stroke. Additionally, warfarin increases the risk of major bleeding and has been associated with vascular calcification. Routine use of warfarin in dialysis for stroke prevention should be discouraged, and therapy should only be reserved for dialysis patients at high risk for thrombo-embolic stroke and carefully monitored if implemented.
Gomes da Silva, Ananília Medeiros; Silbiger, Vivian Nogueira
Atrial fibrillation (AF) is a highly prevalent arrhythmia with pronounced morbidity and mortality. Genetics analysis has established electrophysiological substrates, which determine individual vulnerability to AF occurrence and maintenance. MicroRNAs (miRNAs) found in virtually all organisms function as negative regulators of protein-coding genes. Several studies have suggested a role for miRNAs in the regulation of cardiac excitability and arrhythmogenesis. This review is based on 18 studies conducted between 2009 and 2013 to investigate the association of miRNAs with AF. miRNAs are discussed here as candidate biomarkers for AF in blood and cardiac tissues and as potential targets for AF therapy.
Heck, Patrick M; Lee, Justin M S; Kistler, Peter M
Atrial fibrillation (AF) is an important and often-underrecognized cause of cardiovascular morbidity and mortality. It is an arrhythmia that is commonly seen in the older patient; the median age of patients with AF in early studies was 75 years. Heart failure (HF) is also more frequently seen in the older patient with an approximate doubling of HF prevalence with each decade of life. There is clear interaction between AF and HF, with evidence that HF can lead to AF and AF exacerbates HF. This review focuses on the specific aspect of AF management in elderly patients with HF.
Frontera, Antonio; Wilson, D G; Sekhon, H; Duncan, E R; Thomas, G
Hypertrophic cardiomyopathy (HCM) is one of the most common genetic cardiac conditions. Atrial fibrillation (AF) has been demonstrated to be the most frequent arrhythmia encountered in HCM patients. Research focusing on AF and embolic stroke in HCM patients has been sparse and the sample size of most studies is small. The prognostic significance of AF in HCM patients is still not well known. The aim of this article is to provide further understanding of the anti-coagulation requirement of HCM patients with AF.
Voukalis, Christos; Lip, Gregory Y H; Shantsila, Eduard
Ischaemic strokes resulting from atrial fibrillation (AF) constitute a devastating condition for patients and their carers with huge burden on health care systems. Prophylactic treatment against systemic embolization and ischaemic strokes is the cornerstone for the management of AF. Effective stroke prevention requires the use of the vitamin K antagonists or non-vitamin K oral anticoagulants (NOACs). This article summarises the latest developments in the field of stroke prevention in AF and aims to assist physicians with the choice of oral anticoagulant for patients with non-valvular AF with different risk factor profile.
Weiss, James N; Qu, Zhilin; Shivkumar, Kalyanam
Although considerable progress has been made in developing ablation approaches to cure atrial fibrillation (AF), outcomes are still suboptimal, especially for persistent and long-lasting persistent AF. In this topical review, we review the arrhythmia mechanisms, both reentrant and nonreentrant, that are potentially relevant to human AF at various stages/settings. We describe arrhythmia mapping techniques used to distinguish between the different mechanisms, with a particular focus on the detection of rotors. We discuss which arrhythmia mechanisms are likely to respond to ablation, and the challenges and prospects for improving upon current ablation strategies to achieve better outcomes.
Connolly, Stuart J; Camm, A John; Halperin, Jonathan L; Joyner, Campbell; Alings, Marco; Amerena, John; Atar, Dan; Avezum, Álvaro; Blomström, Per; Borggrefe, Martin; Budaj, Andrzej; Chen, Shih-Ann; Ching, Chi Keong; Commerford, Patrick; Dans, Antonio; Davy, Jean-Marc; Delacrétaz, Etienne; Di Pasquale, Giuseppe; Diaz, Rafael; Dorian, Paul; Flaker, Greg; Golitsyn, Sergey; Gonzalez-Hermosillo, Antonio; Granger, Christopher B; Heidbüchel, Hein; Kautzner, Josef; Kim, June Soo; Lanas, Fernando; Lewis, Basil S; Merino, Jose L; Morillo, Carlos; Murin, Jan; Narasimhan, Calambur; Paolasso, Ernesto; Parkhomenko, Alexander; Peters, Nicholas S; Sim, Kui-Hian; Stiles, Martin K; Tanomsup, Supachai; Toivonen, Lauri; Tomcsányi, János; Torp-Pedersen, Christian; Tse, Hung-Fat; Vardas, Panos; Vinereanu, Dragos; Xavier, Denis; Zhu, Jun; Zhu, Jun-Ren; Baret-Cormel, Lydie; Weinling, Estelle; Staiger, Christoph; Yusuf, Salim; Chrolavicius, Susan; Afzal, Rizwan; Hohnloser, Stefan H
Dronedarone restores sinus rhythm and reduces hospitalization or death in intermittent atrial fibrillation. It also lowers heart rate and blood pressure and has antiadrenergic and potential ventricular antiarrhythmic effects. We hypothesized that dronedarone would reduce major vascular events in high-risk permanent atrial fibrillation. We assigned patients who were at least 65 years of age with at least a 6-month history of permanent atrial fibrillation and risk factors for major vascular events to receive dronedarone or placebo. The first coprimary outcome was stroke, myocardial infarction, systemic embolism, or death from cardiovascular causes. The second coprimary outcome was unplanned hospitalization for a cardiovascular cause or death. After the enrollment of 3236 patients, the study was stopped for safety reasons. The first coprimary outcome occurred in 43 patients receiving dronedarone and 19 receiving placebo (hazard ratio, 2.29; 95% confidence interval [CI], 1.34 to 3.94; P=0.002). There were 21 deaths from cardiovascular causes in the dronedarone group and 10 in the placebo group (hazard ratio, 2.11; 95% CI, 1.00 to 4.49; P=0.046), including death from arrhythmia in 13 patients and 4 patients, respectively (hazard ratio, 3.26; 95% CI, 1.06 to 10.00; P=0.03). Stroke occurred in 23 patients in the dronedarone group and 10 in the placebo group (hazard ratio, 2.32; 95% CI, 1.11 to 4.88; P=0.02). Hospitalization for heart failure occurred in 43 patients in the dronedarone group and 24 in the placebo group (hazard ratio, 1.81; 95% CI, 1.10 to 2.99; P=0.02). Dronedarone increased rates of heart failure, stroke, and death from cardiovascular causes in patients with permanent atrial fibrillation who were at risk for major vascular events. Our data show that this drug should not be used in such patients. (Funded by Sanofi-Aventis; PALLAS ClinicalTrials.gov number, NCT01151137.).
Voukalis, Christos; Lip, Gregory Y.H.; Shantsila, Eduard
Ischaemic strokes resulting from atrial fibrillation (AF) constitute a devastating condition for patients and their carers with huge burden on health care systems. Prophylactic treatment against systemic embolization and ischaemic strokes is the cornerstone for the management of AF. Effective stroke prevention requires the use of the vitamin K antagonists or non-vitamin K oral anticoagulants (NOACs). This article summarises the latest developments in the field of stroke prevention in AF and aims to assist physicians with the choice of oral anticoagulant for patients with non-valvular AF with different risk factor profile. PMID:26981569
Arbelo, Elena; Brugada, Josep; Hindricks, Gerhard; Maggioni, Aldo P; Tavazzi, Luigi; Vardas, Panos; Laroche, Cécile; Anselme, Frédéric; Inama, Giuseppe; Jais, Pierre; Kalarus, Zbigniew; Kautzner, Josef; Lewalter, Thorsten; Mairesse, Georges H; Perez-Villacastin, Julian; Riahi, Sam; Taborsky, Milos; Theodorakis, George; Trines, Serge A
The Atrial Fibrillation Ablation Pilot Study is a prospective registry designed to describe the clinical epidemiology of patients undergoing an atrial fibrillation (AFib) ablation, and the diagnostic/therapeutic processes applied across Europe. The aims of the 1-year follow-up were to analyse how centres assess in routine clinical practice the success of the procedure and to evaluate the success rate and long-term safety/complications. Seventy-two centres in 10 European countries were asked to enrol 20 consecutive patients undergoing a first AFib ablation procedure. A web-based case report form captured information on pre-procedural, procedural, and 1-year follow-up data. Between October 2010 and May 2011, 1410 patients were included and 1391 underwent an AFib ablation (98.7%). A total of 1300 patients (93.5%) completed a follow-up control 367 ± 42 days after the procedure. Arrhythmia documentation was done by an electrocardiogram in 76%, Holter-monitoring in 52%, transtelephonic monitoring in 8%, and/or implanted systems in 4.5%. Over 50% became asymptomatic. Twenty-one per cent were re-admitted due to post-ablation arrhythmias. Success without antiarrhythmic drugs was achieved in 40.7% of patients (43.7% in paroxysmal AF; 30.2% in persistent AF; 36.7% in long-lasting persistent AF). A second ablation was required in 18% of the cases and 43.4% were under antiarrhythmic treatment. Thirty-three patients (2.5%) suffered an adverse event, 272 (21%) experienced a left atrial tachycardia, and 4 patients died (1 haemorrhagic stroke, 1 ventricular fibrillation in a patient with ischaemic heart disease, 1 cancer, and 1 of unknown cause). The AFib Ablation Pilot Study provided crucial information on the epidemiology, management, and outcomes of catheter ablation of AFib in a real-world setting. The methods used to assess the success of the procedure appeared at least suboptimal. Even in this context, the 12-month success rate appears to be somewhat lower to the one
Kawasaki, Shiro; Tanno, Kaoru; Ochi, Akinori; Inokuchi, Koichiro; Chiba, Yuta; Onishi, Yoshimi; Onuma, Yoshimasa; Munetsugu, Yumi; Kikuchi, Miwa; Ito, Hiroyuki; Onuki, Tatsuya; Miyoshi, Fumito; Minoura, Yoshino; Watanabe, Norikazu; Adachi, Taro; Asano, Taku; Kobayashi, Youichi
Background Pulmonary vein isolation (PVI) via catheter ablation has been shown to be a highly effective treatment option for patients with symptomatic paroxysmal atrial fibrillation (AF). The recurrence of AF within 3 months after PVI is not considered to be the result of ablation procedure failure, because early recurrence of AF is not always associated with late recurrence. We examined the usefulness of an external loop recorder with an auto-trigger function (ELR-AUTO) for the detection of atrial fibrillation following PVI to characterize early recurrence and to determine the implications of AF occurrence within 3 months after PVI. Methods Fifty-three consecutive symptomatic patients with paroxysmal AF (age 61.6±12.6 years, 77% male) who underwent PVI and were fitted with ELR-AUTO for 7±2.0 days within 3 months after PVI were enrolled in this study. Results Of the 33 (62.2%) patients who did not have AF recurrence within 3 months after PVI, only 1 patient experienced AF recurrence at 12 months. Seven (35%) of the 20 patients who experienced AF within 3 months of PVI experienced symptomatic AF recurrence at 12 months. The sensitivity, specificity, positive predictive value, and negative predictive value of early AF recurrence for late recurrence were 87.5%, 71.1%, 35.0%, and 96.9%, respectively. Conclusions AF recurrence measured by ELR-AUTO within 3 months after PVI can predict the late recurrence of AF. Freedom from AF in the first 3 months following ablation significantly predicts long-term AF freedom. ELR-AUTO is useful for the detection of symptomatic and asymptomatic AF. PMID:26336538
Recurrence of atrial fibrillation within three months after pulmonary vein isolation for patients with paroxysmal atrial fibrillation: Analysis using external loop recorder with auto-trigger function.
Kawasaki, Shiro; Tanno, Kaoru; Ochi, Akinori; Inokuchi, Koichiro; Chiba, Yuta; Onishi, Yoshimi; Onuma, Yoshimasa; Munetsugu, Yumi; Kikuchi, Miwa; Ito, Hiroyuki; Onuki, Tatsuya; Miyoshi, Fumito; Minoura, Yoshino; Watanabe, Norikazu; Adachi, Taro; Asano, Taku; Kobayashi, Youichi
Pulmonary vein isolation (PVI) via catheter ablation has been shown to be a highly effective treatment option for patients with symptomatic paroxysmal atrial fibrillation (AF). The recurrence of AF within 3 months after PVI is not considered to be the result of ablation procedure failure, because early recurrence of AF is not always associated with late recurrence. We examined the usefulness of an external loop recorder with an auto-trigger function (ELR-AUTO) for the detection of atrial fibrillation following PVI to characterize early recurrence and to determine the implications of AF occurrence within 3 months after PVI. Fifty-three consecutive symptomatic patients with paroxysmal AF (age 61.6±12.6 years, 77% male) who underwent PVI and were fitted with ELR-AUTO for 7±2.0 days within 3 months after PVI were enrolled in this study. Of the 33 (62.2%) patients who did not have AF recurrence within 3 months after PVI, only 1 patient experienced AF recurrence at 12 months. Seven (35%) of the 20 patients who experienced AF within 3 months of PVI experienced symptomatic AF recurrence at 12 months. The sensitivity, specificity, positive predictive value, and negative predictive value of early AF recurrence for late recurrence were 87.5%, 71.1%, 35.0%, and 96.9%, respectively. AF recurrence measured by ELR-AUTO within 3 months after PVI can predict the late recurrence of AF. Freedom from AF in the first 3 months following ablation significantly predicts long-term AF freedom. ELR-AUTO is useful for the detection of symptomatic and asymptomatic AF.
A prospective survey in European Society of Cardiology member countries of atrial fibrillation management: baseline results of EURObservational Research Programme Atrial Fibrillation (EORP-AF) Pilot General Registry.
Lip, Gregory Y H; Laroche, Cécile; Dan, Gheorghe-Andrei; Santini, Massimo; Kalarus, Zbigniew; Rasmussen, Lars Hvilsted; Oliveira, Mário Martins; Mairesse, Georges; Crijns, Harry J G M; Simantirakis, Emmanouil; Atar, Dan; Kirchhof, Paulus; Vardas, Panos; Tavazzi, Luigi; Maggioni, Aldo P
Given the advances in atrial fibrillation (AF) management and the availability of new European Society of Cardiology (ESC) guidelines, there is a need for the systematic collection of contemporary data regarding the management and treatment of AF in ESC member countries. We conducted a registry of consecutive in- and outpatients with AF presenting to cardiologists in nine participating ESC countries. All patients with an ECG-documented diagnosis of AF confirmed in the year prior to enrolment were eligible. We enroled a total of 3119 patients from February 2012 to March 2013, with full data on clinical subtype available for 3049 patients (40.4% female; mean age 68.8 years). Common comorbidities were hypertension, coronary disease, and heart failure. Lone AF was present in only 3.9% (122 patients). Asymptomatic AF was common, particularly among those with permanent AF. Amiodarone was the most common antiarrhythmic agent used (∼20%), while beta-blockers and digoxin were the most used rate control drugs. Oral anticoagulants (OACs) were used in 80% overall, most often vitamin K antagonists (71.6%), with novel OACs being used in 8.4%. Other antithrombotics (mostly antiplatelet therapy, especially aspirin) were still used in one-third of the patients, and no antithrombotic treatment in only 4.8%. Oral anticoagulants were used in 56.4% of CHA2DS2-VASc = 0, with 26.3% having no antithrombotic therapy. A high HAS-BLED score was not used to exclude OAC use, but there was a trend towards more aspirin use in the presence of a high HAS-BLED score. The EURObservational Research Programme Atrial Fibrillation (EORP-AF) Pilot Registry has provided systematic collection of contemporary data regarding the management and treatment of AF by cardiologists in ESC member countries. Oral anticoagulant use has increased, but novel OAC use was still low. Compliance with the treatment guidelines for patients with the lowest and higher stroke risk scores remains suboptimal.
Uslar, Thomas; Anabalón, Jaime
For most atrial fibrillation patients oral anticoagulation constitutes the standard treatment to prevent stroke. However, they carry a risk of bleeding, which is why alternative treatments have been put into practice, such as percutaneous closure of the left atrial appendage. It is not clear whether this is as effective as the conventional treatment with anticoagulants. Searching in Epistemonikos database, which is maintained by screening 30 databases, we identified three systematic reviews including only one pertinent randomized controlled trial. We combined the evidence and generated a summary of findings following the GRADE approach. We concluded that percutaneous left atrial appendage occlusion may decrease stroke and mortality, but the certainty of the evidence is low. The effect on other outcomes is not clear because the certainty of the evidence is very low.
Opacic, Dragan; van Bragt, Kelly A; Nasrallah, Hussein M; Schotten, Ulrich; Verheule, Sander
Atrial fibrillation (AF) is the most common tachyarrhythmia in clinical practice. Over decades of research, a vast amount of knowledge has been gathered about the causes and consequences of AF related to cellular electrophysiology and features of the tissue structure that influence the propagation of fibrillation waves. Far less is known about the role of myocyte metabolism and tissue perfusion in the pathogenesis of AF. However, the rapid rates of electrical activity and contraction during AF must present an enormous challenge to the energy balance of atrial myocytes. This challenge can be met by scaling back energy demand and by increasing energy supply, and there are several indications that both phenomena occur as a result of AF. Still, there is ample evidence that these adaptations fall short of redressing this imbalance, which may represent a driving force for atrial electrical as well as structural remodelling. In addition, several 'metabolic diseases' such as diabetes, obesity, and abnormal thyroid function precipitate some well-known 'culprits' of the AF substrate such as myocyte hypertrophy and fibrosis, while some other AF risk factors, such as heart failure, affect atrial metabolism. This review provides an overview of metabolic and vascular alterations in AF and their involvement in its pathogenesis.
Elikowski, Waldemar; Wróblewski, Dariusz; Małek-Elikowska, Małgorzata; Mazurek, Andrzej; Foremska-Iciek, Joanna; Łazowski, Stanisław
Atrial fibrillation and heart failure are factors predisposing to locally formed intracardiac thrombosis, which is usually localized in left-sided chambers. A case report. The authors present a case of a 50-year-old male with permanent atrial fibrillation and dilated cardiomyopathy in whom recurrent right atrial thrombus was observed. Initially, the lesion was detected in echocardiography while he was hospitalized due to extensive right-sided pneumonia. The thrombus was successfully treated with heparin, followed by warfarin. Even though the patient continued warfarin use properly, there was recurrence of the thrombus two years later during a new episode of heart failure exacerbation. Because the thrombus was resistant to intensified anticoagulation, cardiac surgery was needed. A large (30 x 25 mm) pedunculated thrombus, as well as two smaller ones (each of 10 x 10 mm) attached closely to the atrial wall and previously not detected either by echocardiography or by magnetic resonance imaging, were excited. A partially organized pattern of the thrombi in histological examination can explain lack of anticoagulation effectiveness.
Safaie, Naser; Maghamipour, Nasrollah; Jodati, Ahmad Reza; Mahmoodpoor, Ata; Dashtaki, Leila; Hakimzadeh, Masoud
Patients with valvular heart disease suffer from atrial fibrillation for more than 12 months after valve surgery and have a low probability of remaining in sinus rhythm. We performed an intra-operative procedure similar to surgical maze ІІІ procedure for conversion of this arrhythmia to sinus rhythm. We did this study to evaluate the efficacy of this procedure to restore the sinus rhythm in patients with valvular heart disease. 28 patients with valvular heart disease and chronic persistent atrial fibrillation underwent different combinations of valve surgery and concomitant reduction of left and right atrial size and resection of both atrial auricles in Shahid Madani cardiothoracic center from September 2004 to October 2008. The procedure for atrial fibrillation treatment was performed with cardiopulmonary bypass and after mitral valve replacement. There was one in-hospital death postoperatively because of respiratory failure, but no other complication till 6 months after the operation. Out of 28 patients, 23 were in sinus rhythm one week after the operation, one patient had junctional rhythm after the operation that restored to sinus rhythm and 4 patients had persistent atrial fibrillation. During the 12-month follow up, atrial fibrillation was corrected in 82.14%. Doppler echocardiography in these patients with sinus rhythm demonstrated good atrial contractility. This procedure on both atria is effective and less invasive than the original maze procedure to eliminate the atrial fibrillation, and can be performed in patients with valvular heart disease without increasing the risk of operation.
Heijman, Jordi; Erfanian Abdoust, Pegah; Voigt, Niels; Nattel, Stanley; Dobrev, Dobromir
The complexity of the heart makes an intuitive understanding of the relative contribution of ion channels, transporters and signalling pathways to cardiac electrophysiology challenging. Computational modelling of cardiac cellular electrophysiology has proven useful to integrate experimental findings, extrapolate results obtained in expression systems or animal models to other systems, test quantitatively ideas based on experimental data and provide novel hypotheses that are experimentally testable. While the bulk of computational modelling has traditionally been directed towards ventricular bioelectricity, increasing recognition of the clinical importance of atrial arrhythmias, particularly atrial fibrillation, has led to widespread efforts to apply computational approaches to understanding atrial electrical function. The increasing availability of detailed, atrial-specific experimental data has stimulated the development of novel computational models of atrial-cellular electrophysiology and Ca(2+) handling. To date, more than 300 studies have employed mathematical simulations to enhance our understanding of atrial electrophysiology, arrhythmogenesis and therapeutic responses. Future modelling studies are likely to move beyond current whole-cell models by incorporating new data on subcellular architecture, macromolecular protein complexes, and localized ion-channel regulation by signalling pathways. At the same time, more integrative multicellular models that take into account regional electrophysiological and Ca(2+) handling properties, mechano-electrical feedback and/or autonomic regulation will be needed to investigate the mechanisms governing atrial arrhythmias. A combined experimental and computational approach is expected to provide the more comprehensive understanding of atrial arrhythmogenesis that is required to develop improved diagnostic and therapeutic options. Here, we review this rapidly expanding area, with a particular focus on Ca(2+) handling, and
Yujing, Wang; Congxin, Huang; Shaning, Yang; Lijun, Jin; Xiaojun, Hu; Gang, Wu; Qiang, Xie
This study was designed to investigate whether administration of digitalis could improve mechanical function of left atrial appendage (LAA) and left atrium prospectively in patients with atrial stunning. Fifty-four consecutive patients in whom atrial stunning was observed immediately after cardioversion of chronic atrial fibrillation (AF) were randomized into digitalis or control group for 1 week following cardioversion. Transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) were performed prior to, immediately following, 1 day after and 1 week after cardioversion to measure transmitral flow velocity and LAA flow velocity. Electrical cardioversion of AF elicited significantly slower left atrial appendage peak emptying velocity (LAA-PEV) and peak filling velocity (LAA-PFV) immediately following cardioversion in both groups. 1 day post cardioversion, there were no significant differences in transmitral E wave, A wave, E/A ratio, LAA-PEV, LAA-PFV or left atrial appendage ejection fraction (LAA-EF) between digitalis and control groups. 1 week post cardioversion, no significant differences were found in transmitral E wave, A wave, E/A ratio, LAA-PEV, LAA-PFV or LAA-EF between the two groups. The occurrence rates of spontaneous echo contrast were not significantly different between digitalis and control groups one day and one week post cardioversion. In conclusion, digitalis did not improve left atrial and appendage mechanical dysfunction following cardioversion of chronic AF. Digitalis did not prevent the development of spontaneous echo contrast in left atrial chamber and appendage. This may be due to the fact that digitalis aggravates intracellular calcium overload induced by chronic AF and has a negative effect on ventricular rate.
BenAbda, Rafik; Gunn, Anne; Roberge, Eric; Yang, Ting-Wei
Coronary artery fistula (CAF) is an abnormality in which the coronary artery has an anomalous connection with a venous structure such as the coronary sinus or atrium. CAF is usually congenital, but may be acquired. The prevalence in the general population is low with many asymptomatic and discovered incidentally. When symptomatic, CAF may present with dyspnea, decreasing functional capacity, and/or arrhythmia. We report a case of a young otherwise healthy active duty male with progressive symptoms of dizziness and exertional fatigue with paroxysmal atrial fibrillation. An electrically negative, but symptomatically positive stress test led to further workup with coronary computed tomography angiogram, which unexpectedly revealed large coronary fistulas between the aneurysmal right coronary artery and coronary sinus and the dilated left circumflex artery with probable collateralization to the coronary sinus. Cardiac magnetic resonance imaging and cardiac catheterization supported these findings and demonstrated no evidence of significant shunting.
Berntsson, John; Smith, J Gustav; Nilsson, Peter M; Hedblad, Bo; Melander, Olle; Engström, Gunnar
Background The increasing prevalence of atrial fibrillation and novel therapeutic tools to prevent cardioembolic stroke has increased the need for risk markers. Objectives This study explored the relationship between the midregional sequence of pro-atrial natriuretic peptide (MR-proANP) levels with the risk of atrial fibrillation and stroke, and whether measurement of MR-proANP improves the prediction of these outcomes. Methods MR-proANP was measured in fasting blood samples of 5130 subjects (69% men, mean age 69.2 ± 6.2 years) without a history of atrial fibrillation or stroke from the general population. The incidence of atrial fibrillation and stroke was monitored over a median follow-up of 5.6 years. C-statistics and net reclassification improvement was used to assess the predictive ability of MR-proANP in addition to conventional risk factors. Results Log-normalized MR-proANP was significantly associated with the incidence of atrial fibrillation ( n = 362; hazard ratio (HR); 95% confidence interval (CI) per 1 standard deviation (SD) 2.05, 1.86-2.27) and stroke from all causes ( n = 195; HR 1.30; 95% CI 1.12-1.50). The HR for stroke events related to atrial fibrillation was 1.79 (95% CI 1.25-2.58) per 1 SD. MR-proANP significantly improved the prediction of atrial fibrillation when added to a risk score of conventional risk factors (C statistic 0.69 vs. 0.75), mainly by down-classifying subjects who did not develop atrial fibrillation. A smaller improvement in predictive ability was observed for stroke (C statistic 0.66 vs. 0.68). Conclusion High plasma levels of MR-proANP are associated with the incidence of atrial fibrillation and stroke in the middle-aged and elderly population. MR-proANP may be useful to identify individuals with an increased risk of atrial fibrillation.
Gialdini, Gino; Nearing, Katherine; Bhave, Prashant D.; Bonuccelli, Ubaldo; Iadecola, Costantino; Healey, Jeff S.; Kamel, Hooman
IMPORTANCE Clinically apparent atrial fibrillation increases the risk of ischemic stroke. In contrast, perioperative atrial fibrillation may be viewed as a transient response to physiological stress, and the long-term risk of stroke after perioperative atrial fibrillation is unclear. OBJECTIVE To examine the association between perioperative atrial fibrillation and the long-term risk of stroke. DESIGN, SETTING, AND PARTICIPANTS Retrospective cohort study using administrative claims data on patients hospitalized for surgery (as defined by surgical diagnosis related group codes), and discharged alive and free of documented cerebrovascular disease or preexisting atrial fibrillation from nonfederal California acute care hospitals between 2007 and 2011. Patients undergoing cardiac vs other types of surgery were analyzed separately. MAIN OUTCOMES AND MEASURES Previously validated diagnosis codes were used to identify ischemic strokes after discharge from the index hospitalization for surgery. The primary predictor variable was atrial fibrillation newly diagnosed during the index hospitalization, as defined by previously validated present-on-admission codes. Patients were censored at postdischarge emergency department encounters or hospitalizations with a recorded diagnosis of atrial fibrillation. RESULTS Of 1 729 360 eligible patients, 24 711 (1.43%; 95% CI, 1.41%–1.45%) had new-onset perioperative atrial fibrillation during the index hospitalization and 13 952 (0.81%; 95% CI, 0.79%–0.82%) experienced a stroke after discharge. In a Cox proportional hazards analysis accounting for potential confounders, perioperative atrial fibrillation was associated with subsequent stroke both after noncardiac and cardiac surgery. Type of SurgeryCumulative Rate of Stroke 1 Year AfterHospitalization, % (95% CI)Hazard Ratio (95% CI)PerioperativeAtrial FibrillationNo PerioperativeAtrial FibrillationNoncardiac1.47 (1.24–1.75)0.36 (0.35–0.37)2.0 (1.7–2.3)Cardiac0.99 (0.81–1
Tzikas, Apostolos; Karagounis, Lambros; Bouktsi, Maria; Drevelegas, Antonios; Parcharidou, Despina; Ioannidis, Stathis; Krasopoulos, George; Giannakoulas, George
Left atrial appendage (LAA) occlusion has been introduced into clinical practice as a valuable alternative to oral anticoagulation for stroke prevention in patients with non-valvular atrial fibrillation. In this case presentation we describe the first LAA occlusion in Greece using the Amplatzer Amulet device. We also briefly discuss issues related to procedural safety and multimodality imaging for LAA occlusion.
Vos, M; Golitsyn, S; Stangl, K; Ruda, M; Van Wijk, L; Harry, J; Perry, K; Touboul, P; Steinbeck, G; Wellens, H
Objective—To compare the efficacy and safety of a single dose of ibutilide, a new class III antiarrhythmic drug, with that of DL-sotalol in terminating chronic atrial fibrillation or flutter in haemodynamically stable patients. Design—Double blind, randomised study. Setting—43 European hospitals. Patients—308 patients (mean age 60 years, 70% men, 48% with heart disease) with sustained atrial fibrillation (n = 251) or atrial flutter (n = 57) (duration three hours to 45 days) were randomised to three groups to receive a 10 minute infusion of 1 mg ibutilide (n = 99), 2 mg ibutilide (n = 106), or 1.5 mg/kg DL-sotalol (n = 103). Infusion was discontinued at termination of the arrhythmia. Main outcome measure—Successful conversion of atrial fibrillation or flutter, defined as termination of arrhythmia within one hour of treatment. Results—Both drugs were more effective against atrial flutter than against atrial fibrillation. Ibutilide was superior to DL-sotalol for treating atrial flutter (70% and 56% v 19%), while the high dose of ibutilide was more effective for treating atrial fibrillation than DL-sotalol (44% v 11%) and the lower dose of ibutilide (44% v 20%, p < 0.01). The mean (SD) time to arrhythmia termination was 13 (7) minutes with 2 mg ibutilide, 19 (15) minutes with 1 mg ibutilide, and 25 (17) minutes with DL-sotalol. In all patients, the duration of arrhythmia before treatment was a predictor of arrhythmia termination, although this was less obvious in the group that received 2 mg ibutilide. This dose converted almost 48% of atrial fibrillation that was present for more than 30 days. Concomitant use of digitalis or nifedipine and prolongation of the QTc interval were not predictive of arrhythmia termination. Bradycardia (6.5%) and hypotension (3.7%) were more common side effects with DL-sotalol. Of 211 patients given ibutilide, two (0.9%) who received the higher dose developed polymorphic ventricular tachycardia
da Silva, Rose M.F.L.
Atrial fibrillation is the most frequent arrhythmia in clinical practice, reaching 2% of the people in the world and is associated with systemic embolism. Thus, the use of anticoagulants is indicated if CHA2DS2-VASc score ≥2 or in patients with previous transient ischemic attack or stroke. For decades, warfarin, a vitamin K antagonist, was the only choice for chronic oral anticoagulation. Recently, novel oral anticoagulants (NOACs) have been introduced, offering similar (or better) effectiveness, safety, and convenience to the vitamin K antagonists. Dabigatran was the first NOAC approved and is a direct thrombin inhibitor. Rivaroxaban and apixaban are factor Xa inhibitors. They display rapid onset of action, more predictable of pharmacological profile, less interactions with other drugs, lack of significant effects in the diet, and less risk of intracranial hemorrhage than warfarin. Despite that dose adjustment is necessary for patients with chronic kidney disease or according to body weight, these new drugs do not require regular monitoring. There are recommendations for the start and follow-up therapy with NOACs, planning for cardioversion, ablation and surgical interventions and the management of bleeding. This article is a review of the major studies of the NOACs. The clinical use of these drugs in patients with non-valvular atrial fibrillation is presented. PMID:25470147
Lawrance, Christopher P.; Henn, Matthew C.; Damiano, Ralph J.
Purpose of review The aim of this review is to focus specifically on the indications, evolution of technique, and results of surgical ablation for atrial fibrillation. Recent findings With the introduction of the Cox-Maze IV procedure utilizing bipolar radiofrequency ablation and cryoablation, long-term studies have demonstrated a significant decrease in aortic cross-clamp times and major complications with a comparable rate of restoration of sinus rhythm. New hybrid approaches utilizing both catheter-based ablation and minimally invasive surgical approaches have been developed, but have not been standardized. Early studies have demonstrated reasonable success rates of hybrid procedures, with advantages that include confirmation of conduction block, decreased surgical morbidity, and possibly reduced morbidity. However, hybrid approaches have the disadvantage of significantly increased operative times. Summary The Cox-Maze IV is currently the gold standard for surgical treatment of atrial fibrillation. New hybrid approaches have potential advantages with promising early results, but a standard lesion set, improvement in operative times, and long-term results still need to be evaluated. PMID:25389650
Peshko, Igor; Rubtsov, Vladimir; Vesselov, Leonid; Sigal, Gennady; Laks, Hillel
A fiber photo-catheter has been developed for surgical treatment of atrial fibrillation with laser radiation. Atrial fibrillation (AF) is a heart rhythm abnormality that involves irregular and rapid heartbeats. Recent studies demonstrate the superiority of treating AF disease with optical radiation of the near infrared region. To produce long continuous transmural lesions, solid-state lasers and laser diodes, along with end-emitting fiber catheters, have been used experimentally. The absence of side-emitting flexible catheters with the ability to produce long continuous lesions limits the further development of this technology. In this research, a prototype of an optical catheter, consisting of a flexible 10-cm fiber diffuser has been used to make continuous photocoagulation lesions for effective maze procedure treatments. The system also includes: a flexible optical reflector; a series of openings for rapid self-attachment to the tissue; and an optional closed-loop irrigating chamber with circulating saline to cool the optical diffuser and irrigate the tissue. PMID:19587838
Delanaye, Pierre; Bouquegneau, Antoine; Dubois, Bernard E; Sprynger, Muriel; Mariat, Christophe; Krzesinski, Jean-Marie; Lancellotti, Patrizio
Cardiovascular mortality of hemodialysis patients remains a major problem. The prevalence and incidence of atrial fibrillation in this population are more important than in the general population. The indication of antivitamin K therapy (AVK) in this context of atrial fibrillation must be weighted against the increased risk of bleeding. Unfortunately, and contrary to the general population, an indication of anticoagulation based on embolic or hemorrhagic risk scores is not as clearly established in the hemodialysis population. No prospective randomized study has investigated the benefit/risk balance of anticoagulant treatment in hemodialysis subjects. This article is a review of the current literature on this topic, showing the prevalence of thromboembolic but also bleeding events in the hemodialysis population. The impact of AVK treatment in this specific population is also reviewed. To the best of our knowledge, the indication of treatment must be individualized. Copyright © 2016 Association Société de néphrologie. Published by Elsevier Masson SAS. All rights reserved.
Tozzi, Piergiorgio; Hayoz, Daniel; Thévenaz, Pierrick; Roulet, Jean-Yves; Salchli, Francois; von Segesser, Ludwig K
Chronic atrial fibrillation affects millions of people worldwide. Its surgical treatment often fails to restore the transport function of the atrium. This study first introduces the concept of an atrial assist device (AAD) to restore the pump function of the atrium. The AAD is developed to be totally implantable in the human body with a transcutaneous energy transfer system to recharge the implanted battery. The ADD consists of a motorless pump based on artificial muscle technology, positioned on the external surface of the atrium to compress it and restore its muscular activity. A bench model reproduces the function of a fibrillating atrium to assess the circulatory support that this pump can provide. Atripump (Nanopowers SA, Switzerland) is a dome-shaped silicone-coated nitinol actuator 5 mm high, sutured on the external surface of the atrium. A pacemaker-like control unit drives the actuator that compresses the atrium, providing the mechanical support to the blood circulation. Electrical characteristics: the system is composed of one actuator that needs a minimal tension of 15 V and has a maximum current of 1.5 A with a 50% duty cycle. The implantable rechargeable battery is made of a cell having the following specifications: nominal tension of a cell: 4.1 V, tension after 90% of discharge: 3.5 V, nominal capacity of a cell: 163 mA h. The bench model consists of an open circuit made of latex bladder 60 mm in diameter filled with water. The bladder is connected to a vertically positioned tube that is filled to different levels, reproducing changes in cardiac preload. The Atripump is placed on the outer surface of the bladder. Pressure, volume and temperature changes were recorded. The contraction rate was 1 Hz with a power supply of 12 V, 400 mA for 200 ms. Preload ranged from 15 to 21 cm H(2)O. Maximal silicone membrane temperature was 55 degrees C and maximal temperature of the liquid environment was 35 degrees C. The pump produced a maximal work of 16 x 10
Koskinen, P; Kupari, M; Leinonen, H; Luomanmäki, K
The aetiological role of alcohol in new onset atrial fibrillation was evaluated in a case-control study of 100 consecutive patients aged 21-64 years. Clinical examination, routine diagnostic tests, and echocardiography revealed an underlying disease or other identifiable factor for atrial fibrillation in 65 patients (group 1); 35 patients had idiopathic atrial fibrillation (group 2). The most common diseases associated with atrial fibrillation were ischaemic heart disease (21%), hypertension (13%), and cardiomyopathy (8%). Data on alcohol consumption were obtained by interviewing the patients and their age and sex matched controls on admission. The mean daily alcohol intake of group 2 patients during the week preceding atrial fibrillation was significantly larger than that of either controls or group 1 patients. Compared with controls significantly more patients in both groups with atrial fibrillation had consumed alcohol within two days of the onset of the arrhythmia. Significantly more patients had onset of arrhythmia on Wednesday, Thursday, or Friday than on any other weekday, including patients with high alcohol intake. This study establishes alcohol as an important precipitating factor for new onset atrial fibrillation. PMID:3593617
Pagonas, Nikolaos; Schmidt, Sven; Eysel, Jörg; Compton, Friederike; Hoffmann, Clemens; Seibert, Felix; Hilpert, Justus; Tschöpe, Carsten; Zidek, Walter; Westhoff, Timm H
The introduction of automated oscillometric blood pressure monitors was the basis for today's widespread use of blood pressure self-measurement. However, in atrial fibrillation, there is a controversial debate on the use of oscillometry because there is a high variability of heart rate and stroke volume. To date, the accuracy of oscillometric blood pressure monitoring in atrial fibrillation has only been investigated using auscultatory sphygmomanometry as reference method, which may be biased by arrhythmia as well. We performed a cross-sectional study in 102 patients (52 sinus rhythm, 50 atrial fibrillation) assessing the accuracy of an automated and validated oscillometric upper arm (M5 Professional, Omron) and wrist device (R5 Professional, Omron) to invasively assessed arterial pressure. Blood pressure values were calculated as the mean of 3 consecutive measurements. Systolic and diastolic blood pressure did not significantly differ in patients with sinus rhythm and atrial fibrillation, independent of the method of measurement (P>0.05 each). The within-subject variability of the oscillometric measurements was higher in patients with atrial fibrillation compared with sinus rhythm (P<0.01 each). The biases of systolic and diastolic blood pressure, however, did not significantly differ in presence or absence of atrial fibrillation in Bland-Altmann analysis (P>0.05 each). In conclusion, atrial fibrillation did not significantly affect the accuracy of oscillometric measurements, if 3 repeated measurements were performed.
Hasegawa, Jumpei; Bieber, Brian; Larkina, Maria; Robinson, Bruce M; Wakai, Sachiko; Akizawa, Tadao; Saito, Akira; Fukuhara, Shunichi; Akiba, Takashi
Atrial fibrillation is one of the most common arrhythmias in hemodialysis patients. We evaluated its clinical outcomes among hemodialysis patients with atrial fibrillation in Japan. Using data derived from the Japanese Dialysis Outcomes and Practice Patterns Study, we analyzed backgrounds and outcomes among hemodialysis patients with and without atrial fibrillation in Japan. Among 7002 hemodialysis patients, the prevalence of atrial fibrillation was 5.7% and the incidence was 0.2 per 100 patient-years. Atrial fibrillation was independently associated with all-cause mortality (hazard ratio, 1.32; 95% confidence interval, 1.02-1.71) and cardiovascular events (hazard ratio, 1.39; 95% confidence interval, 1.15-1.68), but not with stroke events (hazard ratio, 0.77; 95% confidence interval, 0.55-1.06) after adjustment for other variables. We conclude that patients with atrial fibrillation experienced higher mortality and more cardiovascular events than did patients without atrial fibrillation, although the risk of stroke was lower than expected.
Jović, A.; Troskot, R.
OBJECTIVE: To evaluate the time course of the recovery of atrial mechanical function after pharmacological cardioversion of chronic atrial fibrillation to sinus rhythm. PATIENTS AND METHODS: 21 patients (12 male, 9 female, aged 37-77 years) with chronic atrial fibrillation (< 6 months) were followed up by serial transmitral pulsed Doppler echocardiography. Echocardiographic studies were performed within the first 24 hours and on day 8, 15, and 30 after cardioversion. RESULTS: There was a significant increase (mean (SD)) in the peak A-wave velocity (from 0.35 (0.10) on day 1 to 0.50 (1.73) on day 8, and thereafter a gradual increase to 0.61 (0.14) m/s on day 30). Similarly, integrated late atrial velocities increased from 4.50 (1.46) on day 1 to 5.61 (1.73) on day 8 and 5.97 (1.47) cm/s2 on day 30. The atrial contribution to total transmitral flow increased significantly from 26 (7)% immediately after conversion of atrial fibrillation to sinus rhythm to 34 (7)% on day 30, indicating the haemodynamic benefit of the restoration of sinus rhythm. Left atrial diameter decreased but not significantly, from 4.11 (0.37) to 3.98 (0.34) cm (P < 0.005). CONCLUSIONS: These results suggest that restoration of atrial mechanical function after pharmacological cardioversion in patients with chronic atrial fibrillation is slow and gradual, as it is after electrical DC restoration of sinus rhythm. This time course may have important implications for determining how long treatment with anticoagulants and antiarrhythmic agents needs to continue in individual patients. It will also influence the clinical assessment of the haemodynamic benefit of restoring sinus rhythm in patients with chronic atrial fibrillation. Images PMID:9038694
Xu, H F; He, Y M; Qian, Y X; Zhao, X; Li, X; Yang, X J
Atrial fibrillation is the most common significant cardiac arrhythmia in clinical practice, but its risk factors remain to be clarified. We have hypothesized that left ventricular posterior wall thickness is an independent risk factor for paroxysmal atrial fibrillation (PAF). A total of 166 consecutive patients with paroxysmal atrial fibrillation were included in this study. Another 166 healthy check-up people, strictly age and sex-matched, were enrolled as controls in the same period. Univariable analysis and multivariable conditional logistic stepwise regression analysis were conducted. Receiver operating characteristic (ROC) curve analysis was performed on those significant indices obtained from the multivariable logistic regression analysis. The multivariable stepwise analysis identified left ventricular posterior wall thickness, left atrial diameter tricuspid insufficiency and residence (countryside) as independent predictors for paroxysmal atrial fibrillation. Receiver operating characteristic curve analysis demonstrated the cutoff values of those risk factors aforementioned. In this strictly age and sex-matched population-based sample, left ventricular posterior wall thickness, left atrial diameter, tricuspid insufficiency and residence were predictive risks for paroxysmal atrial fibrillation. This study offers novel information therapeutically beyond that provided by traditional clinical atrial fibrillation risk factors.
Candan, Ozkan; Gecmen, Cetin; Kalayci, Arzu; Dogan, Cem; Bayam, Emrah; Ozkan, Mehmet
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
Murin, Jan; Naditch-Brûlé, Lisa; Brette, Sandrine; Chiang, Chern-En; O’Neill, James; Steg, P. Gabriel
Background Atrial fibrillation can be categorized into nonpermanent and permanent atrial fibrillation. There is less information on permanent than on nonpermanent atrial fibrillation patients. This analysis aimed to describe the characteristics and current management, including the proportion of patients with successful atrial fibrillation control, of these atrial fibrillation subsets in a large, geographically diverse contemporary sample. Methods and Results Data from RealiseAF, an international, observational, cross-sectional survey of 10,491 patients with atrial fibrillation, were used to characterize permanent atrial fibrillation (N = 4869) and nonpermanent atrial fibrillation (N = 5622) patients. Permanent atrial fibrillation patients were older, had a longer time since atrial fibrillation diagnosis, a higher symptom burden, and were more likely to be physically inactive. They also had a higher mean (SD) CHADS2 score (2.2 [1.3] vs. 1.7 [1.3], p<0.001), and a higher frequency of CHADS2 score ≥2 (67.3% vs. 53.0%, p<0.001) and comorbidities, most notably heart failure. Physicians indicated using a rate-control strategy in 84.2% of permanent atrial fibrillation patients (vs. 27.5% in nonpermanent atrial fibrillation). Only 50.2% (N = 2262/4508) of permanent atrial fibrillation patients were controlled. These patients had a longer time since atrial fibrillation diagnosis, a lower symptom burden, less obesity and physical inactivity, less severe heart failure, and fewer hospitalizations for acute heart failure than uncontrolled permanent atrial fibrillation patients, but with more arrhythmic events. The most frequent causes of hospitalization in the last 12 months were acute heart failure and stroke. Conclusion Permanent atrial fibrillation is a high-risk subset of atrial fibrillation, representing half of all atrial fibrillation patients, yet rate control is only achieved in around half. Since control is associated with lower symptom burden and heart
Nickelsen, M N; Snoer, A; Ali, A M; Wienecke, T
Paroxysmal atrial fibrillation (PAF) is often asymptomatic and increases the risk of ischaemic stroke. Detection of PAF is challenging but crucial because a change of treatment decreases the risk of ischaemic stroke. Post-stroke investigations recommend at least 24-h continuous cardiac rhythm monitoring. Extended monitoring detects more PAF but is limited by costs due to manual analysis. Interpretive software might be a reasonable screening tool. The aim was to validate the performance and utility of Pathfinder SL software compared to manual analysis. In all, 135 ischaemic stroke patients with no prior history of PAF or atrial fibrillation and who had done a 7-day continuous electrocardiogram monitoring (Holter) were included. Manual analysis was compared with Pathfinder SL software including a systematic control of registered events. Seventeen (12.6%) patients were diagnosed with PAF (atrial fibrillation > 30 s). Pathfinder SL software including a systematic control of events registered 16 (94.1%) patients with PAF. Manually 15 (88.2%) patients were detected with PAF. Pathfinder SL had a negative predictive value of 99% and sensitivity of 94%. Pathfinder SL software including a systematic evaluation of events is an acceptable alternative compared to manual analysis in PAF detection following ischaemic stroke. It is less time consuming and therefore a reliable, cheaper alternative compared to manual analysis. © 2016 EAN.
Zhang, Huijuan; Nan, Qun; Liu, Youjun
The aim of this study is to investigate the effects of ablation parameters on thermal distribution during microwave atrial fibrillation catheter ablation, such as ablation time, ablation power, blood condition and antenna placement, and give proper ablative parameters to realise transmural ablation. In this paper, simplified 3D antenna-myocardium-blood finite element method models were built to simulate the endocardial ablation operation. Thermal distribution was obtained based on the coupled electromagnetic-thermal analysis. Under different antenna placement conditions and different microwave power inputs within 60 s, the lesion dimensions (maximum depth, maximum width) of the ablation zones were analysed. The ablation width and depth increased with the ablation time. The increase rate significantly slowed down after 10 s. The maximum temperature was located in 1 mm under the antenna tip when perpendicular to the endocardium, while 1.5 mm away from the antenna axis and 26 mm along the antenna (with antenna length about 30 mm) in the myocardium when parallel to the endocardium. The maximum temperature in the ablated area decreased and the effective ablation area (with the temperature raised to 50°C) shifted deeper into the myocardium due to the blood cooling. The research validated that the microwave antenna can provide continuous long and linear lesions for the treatment of atrial fibrillation. The dimensions of the created lesion widths were all larger than those of the depths. It is easy for the microwave antenna to produce transmural lesions for an atrial wall thickness of 2-6 mm by adjusting the applied power and ablation time.
Tenekecioglu, Erhan; Agca, Fahriye Vatansever; Ozluk, Ozlem Arican; Karaagac, Kemal; Demir, Serafettin; Peker, Tezcan; Kuzeytemiz, Mustafa; Senturk, Muhammed; Yılmaz, Mustafa
Background Hypertension is the most prevalent and modifiable risk factor for atrial fibrillation. The pressure overload in the left atrium induces pathophysiological changes leading to alterations in contractile function and electrical properties. Objective In this study our aim was to assess left atrial function in hypertensive patients to determine the association between left atrial function with paroxysmal atrial fibrillation (PAF). Method We studied 57 hypertensive patients (age: 53±4 years; left ventricular ejection fraction: 76±6.7%), including 30 consecutive patients with PAF and 30 age-matched control subjects. Left atrial (LA) volumes were measured using the modified Simpson's biplane method. Three types of LA volume were determined: maximal LA(LAVmax), preatrial contraction LA(LAVpreA) and minimal LA volume(LAVmin). LA emptying functions were calculated. LA total emptying volume = LAVmax−LAVmin and the LA total EF = (LAVmax-LAVmin )/LAVmax, LA passive emptying volume = LAVmax− LAVpreA and the LA passive EF = (LAVmax-LAVpreA)/LAVmax, LA active emptying volume = LAVpreA−LAVmin and LA active EF = (LAVpreA-LAVmin )/LAVpreA. Results The hypertensive period is longer in hypertensive group with PAF. LAVmax significantly increased in hypertensive group with PAF when compared to hypertensive group without PAF (p=0.010). LAAEF was significantly decreased in hypertensive group with PAF as compared to hypertensive group without PAF (p=0.020). A' was decreased in the hypertensive group with PAF when compared to those without PAF (p = 0.044). Conclusion Increased LA volume and impaired LA active emptying function was associated with PAF in untreated hypertensive patients. Longer hypertensive period is associated with PAF. PMID:24676227
Budeus, Marco; Felix, Oliver; Hennersdorf, Marcus; Wieneke, Heinrich; Erbel, Raimund; Sack, Stefan
Paroxysmal atrial fibrillation (PAF) transits to permanent atrial fibrillation (PEAF). The current study was to determine whether a P wave-triggered P wave signal averaged electrocardiogram (P-SAECG) and chemoreflexsensitivity (CHRS) are useful to predict a conversion to PEAF in patients with PAF. The filtered P wave duration (FPD) and the root mean square voltage of the last 20 ms of the P wave (RMS 20) were measured by P-SAECG. The ratio between the difference of RR intervals in the ECG and venous pO2 before and after 5-minutes oxygen inhalation is measured (ms/mmHg) for the determination of CHRS. A total of 180 patients with PAF were enrolled and followed for a mean of 22.5 months. PEAF occurred in 38 patients (21%) and these patients had a significantly larger left atrial size (43.2 +/- 4.9 vs. 41.0 +/- 5.4 mm, P = 0.021), a significantly longer FPD (158.8 +/- 18.2 vs. 136.7 +/- 16.6 ms, P < 0.0001), and a significantly lower CHRS (1.96 +/- 0.99 vs. 2.44 +/- 1.19 ms/mmHg, P = 0.024) than patients with PAF. Patients with PEAF tended to have a lower RMS 20 (2.38 +/- 0.65 vs. 2.75 +/- 1.18 microV, P = 0.067) than patients with PAF. The chi(2) test showed that the combination of FPD > or = 145 ms, RMS 20 < or = 3.0 microV, left atrial size > or = 41 mm, and CHRS < or = 2.0 ms/mmHg had the best predictive power for PEAF. Patients who fulfilled these criteria had a 12-fold increased risk for a conversion from PAF to PEAF. Our results show that a P-SAECG, an analysis of CHRS, and left atrial enlargement are clinical predictors of a progression from PAF to PEAF.
Zhang, Youhua; Dedkov, Eduard I.; Teplitsky, Diana; Weltman, Nathan Y.; Pol, Christine J.; Rajagopalan, Viswanathan; Lee, Bianca; Gerdes, A. Martin
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
Vidaurri, A; Pastelín, G; Méndez, R; Cárdenas, M
Quinidine gluconate was administered slowly by intravenous infusion to 20 patients with atrial fibrillation. Nineteen of them had rheumatic heart disease and the other one had Ebstein's disease. The first ten patients received 0.027 mg/kg/min during 6 hs or less if they returned to normal sinus rhythm (SR). The other ten received 0.041 mg/kg/min with the same protocol. Plasma quinidine concentrations were determined in all patients. Atrial functional refractory period was measured in five of the patients returning to normal sinus rhythm. Six patients in the first group were returned to SR. The required time of infusion was 4.2 hs. The maximal quinidine plasma level was 1.91 ug/ml. In the Second group; five patients returned to normal sinus rhythm, four of them in a mean time of 4.75 hs ofinfusion and the other one spontaneously 11 hs after the infusion was finished. The maximal quinidine plasma level in this group was 4.7 ug/ml. Side effects were observed in five patients. Diarrhea in one, vomiting in one, hypotension in two atrial flutter with 1: 1 A-V conduction in one.
Risom, Signe S; Zwisler, Ann-Dorthe; Johansen, Pernille P; Sibilitz, Kirstine L; Lindschou, Jane; Gluud, Christian; Taylor, Rod S; Svendsen, Jesper H; Berg, Selina K
Exercise-based cardiac rehabilitation may benefit adults with atrial fibrillation or those who had been treated for atrial fibrillation. Atrial fibrillation is caused by multiple micro re-entry circuits within the atrial tissue, which result in chaotic rapid activity in the atria. To assess the benefits and harms of exercise-based rehabilitation programmes, alone or with another intervention, compared with no-exercise training controls in adults who currently have AF, or have been treated for AF. We searched the following electronic databases; CENTRAL and the Database of Abstracts of Reviews of Effectiveness (DARE) in the Cochrane Library, MEDLINE Ovid, Embase Ovid, PsycINFO Ovid, Web of Science Core Collection Thomson Reuters, CINAHL EBSCO, LILACS Bireme, and three clinical trial registers on 14 July 2016. We also checked the bibliographies of relevant systematic reviews identified by the searches. We imposed no language restrictions. We included randomised controlled trials (RCT) that investigated exercise-based interventions compared with any type of no-exercise control. We included trials that included adults aged 18 years or older with atrial fibrillation, or post-treatment for atrial fibrillation. Two authors independently extracted data. We assessed the risk of bias using the domains outlined in the Cochrane Handbook for Systematic Reviews of Interventions. We assessed clinical and statistical heterogeneity by visual inspection of the forest plots, and by using standard Chi² and I² statistics. We performed meta-analyses using fixed-effect and random-effects models; we used standardised mean differences where different scales were used for the same outcome. We assessed the risk of random errors with trial sequential analysis (TSA) and used the GRADE methodology to rate the quality of evidence, reporting it in the 'Summary of findings' table. We included six RCTs with a total of 421 patients with various types of atrial fibrillation. All trials were
Stiermaier, Thomas; Santoro, Francesco; Eitel, Charlotte; Graf, Tobias; Möller, Christian; Tarantino, Nicola; Guastafierro, Francesca; Di Biase, Matteo; Thiele, Holger; Brunetti, Natale D; Eitel, Ingo
Takotsubo syndrome (TTS) is associated with a considerable risk of complications during the acute phase and substantial long-term mortality rates. Concomitant atrial fibrillation may have an impact on outcome in these patients. Aim of this study was to assess the prevalence and prognostic relevance of atrial fibrillation in TTS. We performed an international, multicenter study including 387 TTS patients consecutively enrolled at 3 centers. Atrial fibrillation was defined as known history before admission or documented episodes during hospital stay. Long-term mortality was evaluated in median 2.9years after the acute event. Atrial fibrillation was found in 97 TTS patients (25.1%) and was associated with older age (p<0.01), less emotional triggers (p=0.03), higher incidence of cardiogenic shock (p<0.01), lower left ventricular ejection fraction (p<0.01), and a prolonged hospital stay (p<0.01). Determinants of atrial fibrillation at admission (n=34 patients; 9.0%) in multivariate logistic regression analysis were age (p=0.001) and cardiogenic shock (p=0.013). Long-term mortality was significantly higher in TTS patients with as compared to patients without atrial fibrillation (35.2% versus 15.3%; hazard ratio 3.02, 95% confidence interval 1.90-4.78; p<0.001). In multivariate Cox regression analysis atrial fibrillation was identified as an independent determinant of outcome even after adjustment for clinical variables, left ventricular functional parameters (ballooning pattern, ejection fraction), and cardiogenic shock. In TTS patients, atrial fibrillation is frequent and associated with increased long-term mortality rates. Furthermore, our study identifies atrial fibrillation as an independent predictor of outcome and a potential tool for risk stratification in TTS. Copyright © 2017. Published by Elsevier B.V.
Lowres, Nicole; Krass, Ines; Neubeck, Lis; Redfern, Julie; McLachlan, Andrew J; Bennett, Alexandra A; Freedman, S Ben
Atrial fibrillation guidelines advocate screening to identify undiagnosed atrial fibrillation. Community pharmacies may provide an opportunistic venue for such screening. To explore the experience of implementing an atrial fibrillation screening service from the pharmacist's perspective including: the process of study implementation; the perceived benefits; the barriers and enablers; and the challenges for future sustainability of atrial fibrillation screening within pharmacies. Setting Interviews were conducted face-to-face in the pharmacy or via telephone, according to pharmacist preference. The 'SEARCH-AF study' screened 1000 pharmacy customers aged ≥65 years using an iPhone electrocardiogram, identifying 1.5 % with undiagnosed atrial fibrillation. Nine pharmacists took part in semi-structured interviews. Interviews were transcribed in full and thematically analysed. Qualitative analysis of the experience of implementing an AF screening service from the pharmacist's perspective. Four broad themes relating to service provision were identified: (1) interest and engagement in atrial fibrillation screening by pharmacists, customers, and doctors with the novel, easy-to-use electrocardiogram technology serving as an incentive to undergo screening and an education tool for pharmacists to use with customers; (2) perceived benefits to the pharmacist including increased job satisfaction, improvement in customer relations and pharmacy profile by fostering enhanced customer care and the educational role of pharmacists; (3) implementation barriers including managing workflow, and enablers such as personal approaches for recruitment, and allocating time to discuss screening process and fears; and, (4) potential for sustainable future implementation including remuneration linked to government or pharmacy incentives, combined cardiovascular screening, and automating sections of risk-assessments using touch-screen technology. Atrial fibrillation screening in pharmacies is well
Schreiner, Andrew D; Keith, Brad A; Abernathy, Karen E; Zhang, Jingwen; Brzezinski, Walter A
Endurance exercise plays a role in cardiovascular risk reduction, but may also be a risk factor for atrial fibrillation. This study was performed to assess the prevalence of atrial fibrillation in a population of long-term, competitive swimmers compared with patients within an internal medicine clinic with known risk factors for atrial fibrillation such as diabetes mellitus and hypertension. This cross-sectional study utilized survey data comparing the prevalence of atrial fibrillation in swimmers to a general internal medicine population. A multi-national group of swimmers over the age of 60 were surveyed, and a chart review was performed on a random sample of age-matched internal medicine patients. The primary outcome was the diagnosis of atrial fibrillation. Univariate analysis was used for means of proportions of the responses, and a multivariate logistic regression analysis was performed with diagnosis of atrial fibrillation as the dependent variable. Forty-nine swimmers completed surveys and 100 age-matched internal medicine patients underwent chart review. Swimmers reported atrial fibrillation in 13 cases (26.5 %) compared to 7 (7 %) in the comparison group (p = 0.001). A diagnosis of hypertension or diabetes mellitus was present in 23 (46.9 %) and 1 (2 %) of the swimmers, respectively, as compared to 72 (72 %, p = 0.003) and 32 (32 %, p < 0.001) in the comparison group. Age, presence of diabetes mellitus, and swimming history were variables included in the logistic regression, in relation to atrial fibrillation. Swimming was associated with an odds ratio of 8.739 (95 % CI 2.290 to 33.344, p = 0.015). Long-term, competitive swimmers have an increased prevalence of atrial fibrillation compared to internal medicine patients, despite the higher burden of diabetes mellitus and hypertension in the internal medicine group.
Kalil, Carlos; Bartholomay, Eduardo; Borges, Anibal; Gazzoni, Guilherme; de Lima, Edimar; Etchepare, Renata; Moraes, Rafael; Sussenbach, Carolina; Andrade, Karina; Kalil, Renato
Background Radiofrequency catheter ablation guided by electroanatomical mapping is currently an important therapeutic option for the treatment of atrial fibrillation. The complexity of the procedure, the several techniques used and the diversity of the patients hinder the reproduction of the results and the indication for the procedure. Objective To evaluate the efficacy and factors associated with recurrence of atrial fibrillation. Methods Prospective cohort study with consecutive patients submitted to atrial fibrillation ablation treatment guided by electroanatomical mapping. The inclusion criteria were as follows: minimum age of 18 years; presence of paroxysmal, persistent or long-standing persistent AF; AF recording on an electrocardiogram, exercise testing or Holter monitoring (duration longer than 15 minutes); presence of symptoms associated with AF episodes; AF refractoriness to, at least, two antiarrhythmic drugs, one of which being amiodarone, or impossibility to use antiarrhythmic drugs. Results The study included 95 patients (age 55 ± 12 years, 84% men, mean CHADS2 = 0.8) who underwent 102 procedures with a median follow-up of 13.4 months. The recurrence-free rate after the procedure was 75.5% after 12 months. Atrial fibrillation recurred as follows: 26.9% of patients with paroxysmal and persistent atrial fibrillation; 45.8% of patients with long-standing persistent atrial fibrillation (p = 0.04). Of the analyzed variables, the increased size of the left atrium has proven to be an independent predictor of atrial fibrillation recurrence after the procedure (HR = 2.58; 95% CI: 1.26-4.89). Complications occurred in 4.9% of the procedures. Conclusion Atrial fibrillation ablation guided by electroanatomical mapping has shown good efficacy. The increase in left atrium size was associated with atrial fibrillation recurrence. PMID:24162471
Korompoki, Eleni; Del Giudice, Angela; Hillmann, Steffi; Malzahn, Uwe; Gladstone, David J; Heuschmann, Peter; Veltkamp, Roland
Background and purpose The detection rate of atrial fibrillation has not been studied specifically in transient ischemic attack (TIA) patients although extrapolation from ischemic stroke may be inadequate. We conducted a systematic review and meta-analysis to determine the rate of newly diagnosed atrial fibrillation using different methods of ECG monitoring in TIA. Methods A comprehensive literature search was performed following a pre-specified protocol the PRISMA statement. Prospective observational studies and randomized controlled trials were considered that included TIA patients who underwent cardiac monitoring for >12 h. Primary outcome was frequency of detection of atrial fibrillation ≥30 s. Analyses of subgroups and of duration and type of monitoring were performed. Results Seventeen studies enrolling 1163 patients were included. The pooled atrial fibrillation detection rate for all methods was 4% (95% CI: 2-7%). Yield of monitoring was higher in selected (higher age, more extensive testing for arrhythmias before enrolment, or presumed cardioembolic/cryptogenic cause) than in unselected cohorts (7% vs 3%). Pooled mean atrial fibrillation detection rates rose with duration of monitoring: 4% (24 h), 5% (24 h to 7 days) and 6% (>7 days), respectively. Yield of non-invasive was significantly lower than that of invasive monitoring (4% vs. 11%). Significant heterogeneity was observed among studies (I(2)=60.61%). Conclusion This first meta-analysis of atrial fibrillation detection in TIA patients finds a lower atrial fibrillation detection rate in TIA than reported for IS and TIA cohorts in previous meta-analyses. Prospective studies are needed to determine actual prevalence of atrial fibrillation and optimal diagnostic procedure for atrial fibrillation detection in TIA.
Jenkins, J; Noh, K H; Guezennec, A; Bump, T; Arzbaecher, R
This study compares the performance of three detection algorithms for the recognition of atrial fibrillation in chronic pacing leads. Multiple serial recordings were obtained of wideband and filtered electrograms from chronic atrial and ventricular leads in dogs for a period up to 55 days following implantation. Each dog was recorded in sinus rhythm and induced atrial fibrillation. Four days were chosen for processing: The day of implantation and a day in the first, second or third, and fifth weeks. Three signal processing methods were assessed for performance in detection of atrial fibrillation: software recognition of rate with automatic threshold control, amplitude distribution, and frequency spectral analysis. A software trigger for rate determination was adjusted to thresholds of 10, 20, and 30% of maximum baseline-to-peak amplitude. At 10%, a rate boundary anywhere between 420 and 560 beats per minute (bpm) perfectly separated atrial fibrillation from sinus rhythm even though atrial electrograms were contaminated with large QRS deflections and double-sensing was present. At 20% and 30%, a rate boundary around 300 bpm could be used, but sensitivity and specificity were reduced to 90%. In amplitude distribution analysis, a percent of time within a baseline window provided perfect separation of atrial fibrillation from sinus rhythm. In all cases, the signal was within this window less than 43% of the time in atrial fibrillation, and more than 43% in sinus rhythm. In spectral analysis, frequency bands were examined for power content. In the 6 to 30 Hz band atrial fibrillation contained the greater power. Choosing 58% of total power as a discriminant, sensitivity and specificity of atrial fibrillation detection were 100% and 95% respectively.
Gonçalves, Flavio Donizete; Leite, Valdir Gonçalves; Leite, Vanusa Gonçalves; Maia, Marcelo Alves; Gomes, Otoni Moreira; Lima, Melchior Luiz; Osterne, Evandro César Vidal; Kallás, Elias
Introduction The result of surgical ablation of atrial fibrillation remains controversial, although prospective and randomized studies have shown significant differences in the return to sinus rhythm in patients treated with ablation versus control group. Surgery of the Labyrinth, proposed by Cox and colleagues, is complex and increases the morbidity rate. Therefore, studies are needed to confirm the impact on clinical outcomes and quality of life of these patients. Objective To analyze the results obtained in the treatment of atrial fibrillation by surgical approach, by Gomes procedure, for mitral valve surgery in patients with rheumatic heart disease associated with chronic atrial fibrillation. Methods We studied 20 patients with mitral valve dysfunction of rheumatic etiology, evolving with chronic atrial fibrillation, submitted to surgical treatment of valvular dysfunction and atrial fibrillation by Gomes procedure. Results The mean duration of infusion ranged from 65.8±11.22 and aortic clamping of 40.8±7.87 minutes. Of 20 patients operated, 19 (95%) patients were discharged with normal atrial heart rhythm. One (5%) patient required permanent endocardial pacing. In the postoperative follow-up of six months, 18 (90%) patients continued with regular atrial rhythm, one (5%) patient returned to atrial fibrillation and one (5%) patient continued to require endocardial pacemaker to maintain regular rhythm. Conclusion Gomes procedure associated with surgical correction of mitral dysfunction simplified the surgical ablation of atrial fibrillation in patients with rheumatic mitral valve disease and persistent atrial fibrillation. The results showed that it is a safe and effective procedure. PMID:27849305
Haïssaguerre, M; Jaïs, P; Shah, D C; Takahashi, A; Hocini, M; Quiniou, G; Garrigue, S; Le Mouroux, A; Le Métayer, P; Clémenty, J
Atrial fibrillation, the most common sustained cardiac arrhythmia and a major cause of stroke, results from simultaneous reentrant wavelets. Its spontaneous initiation has not been studied. We studied 45 patients with frequent episodes of atrial fibrillation (mean [+/-SD] duration, 344+/-326 minutes per 24 hours) refractory to drug therapy. The spontaneous initiation of atrial fibrillation was mapped with the use of multielectrode catheters designed to record the earliest electrical activity preceding the onset of atrial fibrillation and associated atrial ectopic beats. The accuracy of the mapping was confirmed by the abrupt disappearance of triggering atrial ectopic beats after ablation with local radio-frequency energy. A single point of origin of atrial ectopic beats was identified in 29 patients, two points of origin were identified in 9 patients, and three or four points of origin were identified in 7 patients, for a total of 69 ectopic foci. Three foci were in the right atrium, 1 in the posterior left atrium, and 65 (94 percent) in the pulmonary veins (31 in the left superior, 17 in the right superior, 11 in the left inferior, and 6 in the right inferior pulmonary vein). The earliest activation was found to have occurred 2 to 4 cm inside the veins, marked by a local depolarization preceding the atrial ectopic beats on the surface electrocardiogram by 106+/-24 msec. Atrial fibrillation was initiated by a sudden burst of rapid depolarizations (340 per minute). A local depolarization could also be recognized during sinus rhythm and abolished by radiofrequency ablation. During a follow-up period of 8+/-6 months after ablation, 28 patients (62 percent) had no recurrence of atrial fibrillation. The pulmonary veins are an important source of ectopic beats, initiating frequent paroxysms of atrial fibrillation. These foci respond to treatment with radio-frequency ablation.
Ladavich, Steven; Ghoraani, Behnaz
In this study we propose a novel atrial activity-based method for atrial fibrillation (AF) identification that detects the absence of normal sinus rhythm (SR) P-waves from the surface ECG. The proposed algorithm extracts nine features from P-waves during SR and develops a statistical model to describe the distribution of the features. The Expectation-Maximization algorithm is applied to a training set to create a multivariate Gaussian Mixture Model (GMM) of the feature space. This model is used to identify P-wave absence (PWA) and, in turn, AF. An optional post-processing stage, which takes a majority vote of successive outputs, is applied to improve classier performance. The algorithm was tested on 20 records in the MIT-BIH Atrial Fibrillation Database. Classification combining seven beats showed a sensitivity of 99.28%, a specificity of 90.21%. The presented algorithm has a classification performance comparable to current Heartrate-based algorithms yet is rate-independent and capable of making an AF determination in a few beats.
Kainuma, Satoshi; Masai, Takafumi; Yoshitatsu, Masao; Miyagawa, Shigeru; Yamauchi, Takashi; Takeda, Koji; Morii, Eiichi; Sawa, Yoshiki
Atrial dilatation and fibrosis are considered to be important factors in the occurrence and maintenance of atrial fibrillation (AF). However, the relationship between those structural remodeling and postoperative sinus conversions after a maze operation has been rarely studied. The purpose of this study was to determine whether pathological evaluation of atrial tissues was useful for predicting an unsuccessful maze operation in patients with valvular AF. Between March 2006 and June 2007, left-atrial tissues in the posterior wall and right-atrial appendage were obtained from 47 consecutive patients (24 patients with chronic AF, and 23 with sinus rhythm) undergoing mitral valve surgery (MVS). A concomitant maze operation was performed for all patients with chronic AF. Atrial cell diameters were measured using hematoxylin and eosin staining, and quantitative assessment of atrial fibrosis was performed with Masson trichrome staining using an image analyzer (Image Processor for Analytical Pathology, Sumika Technoservice Co., Hyogo, Japan). Successful MVS was performed for all patients and there were no complications associated with tissue sampling. Patients with chronic AF had more advanced histological features in both atria as compared with those with sinus rhythm. Sixteen of 24 patients, who underwent a maze operation, had successfully restored sinus rhythm (successful maze group), while that in the remaining eight was not restored (unsuccessful maze group). Patients in the unsuccessful maze group had a larger left-atrial dimension and cardiothoracic ratio as compared with those in the successful group, whereas the duration of AF was not significantly different. Patients in the unsuccessful maze group also had greater hypertrophy of cardiomyocytes and more extensive intercellular fibrosis in the left atrium, while there were no differences for right-atrial pathological features between the groups. Multivariate logistic analysis confirmed that a larger amount of left-atrial
Clementy, Nicolas; Desprets, Laurent; Pierre, Bertrand; Lallemand, Bénédicte; Simeon, Edouard; Brunet-Bernard, Anne; Babuty, Dominique; Fauchier, Laurent
Similar predisposing factors are found in most types of atrial arrhythmias. The incidence of atrial fibrillation (AF) among patients with atrial flutter is high, suggesting similar outcomes in patients with those arrhythmias. We sought to investigate the long-term outcomes and prognostic factors of patients with AF and/or atrial flutter with contemporary management using radiofrequency ablation. In an academic institution, we retrospectively examined the clinical course of 8,962 consecutive patients admitted to our department with a diagnosis of AF and/or atrial flutter. After a median follow-up of 934 ± 1,134 days, 1,155 deaths and 715 stroke and/thromboembolic (TE) events were recorded. Patients with atrial flutter undergoing cavotricuspid isthmus ablation (n = 875, 37% with a history of AF) had a better survival rate than other patients (hazard ratio [HR] 0.35, 95% confidence interval [CI] 0.25 to 0.49, p <0.0001). Using Cox proportional hazards model and propensity score model, after adjustment for main other confounders, ablation for atrial flutter was significantly associated with a lower risk of all-cause mortality (HR 0.55, 95% CI 0.36 to 0.84, p = 0.006) and stroke and/or TE events (HR 0.53, 95% CI 0.30 to 0.92, p = 0.02). After ablation, there was no significant difference in the risk of TE between patients with a history of AF and those with atrial flutter alone (HR 0.83, 95% CI 0.41 to 1.67, p = 0.59). In conclusion, in patients with atrial tachyarrhythmias, those with atrial flutter with contemporary management who undergo cavotricuspid isthmus radiofrequency ablation independently have a lower risk of stroke and/or TE events and death of any cause, whether a history of AF is present or not. Copyright © 2014 Elsevier Inc. All rights reserved.
Schnabel, Renate B.; Yin, Xiaoyan; PhilimonGona; Larson, Martin G.; Beiser, Alexa S.; McManus, David D.; Newton-Cheh, Christopher; Lubitz, Steven A.; Magnani, Jared W.; Ellinor, Patrick T.; SudhaSeshadri; Wolf, Philip A; Vasan, Ramachandran S.; Benjamin, Emelia J.; Levy, Daniel
Summary Background Comprehensive long-term data on atrial fibrillation trends in men and women are scant. Methods We investigated trends in atrial fibrillation incidence, prevalence, and risk factors, and in stroke and mortality following its onset in Framingham Heart Study participants (n=9511) from 1958 to 2007. To accommodate sex differences in atrial fibrillation risk factors and disease manifestations, sex-stratified analyses were performed. Findings During 50 years of observation (202,417 person-years), there were 1,544 new-onset atrial fibrillation cases (46.8% women). We observed about a fourfold increase in the age-adjusted prevalence and more than a tripling in age-adjusted incidence of atrial fibrillation (prevalence 20.4 versus 96.2 per 1000 person-years in men; 13.7 versus 49.4 in women; incidence rates in first versus last decade 3.7 versus 13.4 per 1000 person-years in men; 2.5 versus 8.6 in women, ptrend<0.0001). For atrial fibrillation diagnosed by ECG during routine Framingham examinations, age-adjusted prevalence increased (12.6versus 25.7 per 1000 person-years in men; 8.1 versus 11.8 in women, ptrend<0.0001). The age-adjusted incidence increased, but did not achieve statistical significance. Although the prevalence of most risk factors changed over time, their associated hazards for atrial fibrillation changed little. Multivariable-adjusted proportional hazards models revealed a 73.5% decline in stroke and a 25.4% decline in mortality following atrial fibrillation onset (ptrend=0.0001, ptrend=0.003, respectively). Interpretation Our data suggest that observed trends of increased incidence of atrial fibrillation in the community were partially due to enhanced surveillance. Stroke occurrence and mortality following atrial fibrillation onset declined over the decades, and prevalence increased approximately fourfold. The hazards for atrial fibrillation risk factors remained fairly constant. Our data indicate a need for measures to enhance early
Kaufman, Kenneth R; Velez, Arnaldo E; Wong, Stephen; Mani, Ram
Lacosamide (LCM) is a novel antiepileptic drug (AED) approved by the FDA for adjunctive treatment of partial epilepsy with and without secondary generalization. Lacosamide dose-dependent dysrhythmias (PR-interval prolongation, AV block, and atrial fibrillation/flutter) have been reported. This case represents the first instance of LCM-induced atrial fibrillation following a low loading dose (200 mg). Risk factors for atrial fibrillation are addressed and discussed in the context of this case. Full cardiac history is recommended prior to patients being initiated on LCM. Cardiac monitoring may be required for at-risk patients on LCM. Clinicians need to be cognizant of this potential adverse effect.
Melo, J Q; Neves, J; Adragão, P; Ribeiras, R; Ferreira, M M; Bruges, L; Canada, M; Ramos, T
Several medical, interventional and surgical techniques are used to treat atrial fibrillation, aimed at different goals and having variable success rates. To be able to assess and compare all these techniques a methodology of study and a classification is proposed. We developed a five grade score, named the Santa Crus Score, based upon the post-operative atrial rhythm and the effective atrial contraction. Score 0 corresponds to a persistence of atrial fibrillation, the presence of a regular rhythm is grade 1, 2 or 3 if there is no atrial contraction; right atrial contraction; or bilateral atrial contraction, respectively. Score 4 corresponds to sinus rhythm and bilateral atrial contraction. Surgery for atrial fibrillation was performed on 51 patients since 1992. All patients but two had associated mitrial surgery. Three different maze techniques were performed on 17 patients and the pulmonary veins isolation procedure on 34 patients. Patients were reassessed at 1, 6, 12, 24 and 36 months. After the maze I procedure atrial fibrillation eradication was achieved in 88% of patients but none scored 4. Three patients changed score during the first year. All maze III patients scored 0 initially and one changed to score 3 in the first year. Sixty percent of the maze IIIA patients scored 4, but one evolved to score 0 at 6 months. The pulmonary veins isolation technique eliminated atrial fibrillation in 71% of the patients initially, and in 60% after 1 year, and achieved a score of 4 in a third of the patients. This classification considers the intermediate grades of success that can occur with absence of atrial fibrillation and is applicable to all forms of therapy.
Li, YanGuang; Chen, FuKun; Deng, Long; Lin, Kun; Shi, Xiangmin; Zhaoliang, Shan; Wang, YuTang
Paroxysmal atrial fibrillation (PAF) can increase thrombogenesis risk, especially in the left atrium (LA). The exact mechanism is still unclear. We assessed the effects of PAF on endothelial function, and investigated if febuxostat (FX) can attenuate endothelial dysfunction by inhibition of xanthine oxidase (XO). Eighteen male New Zealand white rabbits were divided randomly into sham-operated (S), PAF (P) or FX+pacing (FP) groups. Group P and group FP received rapid atrial pacing (RAP). Group FP was administered febuxostat (FX) for 7days before RAP. Post-procedure, blood samples were collected from the LA, right atrium (RA) and peripheral circulation. Tissues from the LA and RA were obtained. Endothelial dysfunction (thrombomodulin [TM], von Willebrand factor [VWF], asymmetric dimethylarginine [ADMA]), and indirect thrombin generation (thrombin-antithrombin complex [TAT], prothrombin fragment 1+2 [F1.2]) and oxidative stress in atrial tissue (xanthine oxidase [XO], superoxide dismutase [SOD], malondialdehyde [MDA]) were measured using an Enzyme-linked immunosorbent assay. Atrial endothelial expression of TM and VWF was measured by histology/western blotting. Endothelial dysfunction (TM, VWF, ADMA), TAT generation and oxidative stress (XO, SOD, MDA) in group P were more significant compared with that in group S (p<0.05, respectively). In group P, all of these changes occurred to a greater extent in the LA compared with those in the RA or peripheral circulation. In group FP, FX attenuated endothelial dysfunction and reduced TAT levels by inhibition of XO-mediated oxidative stress. PAF can lead to endothelial dysfunction and TAT generation by XO-mediated oxidative stress. The LA is more susceptible to these effects. FX can attenuate these changes by inhibition XO and XO-mediated oxidative stress. Copyright © 2016. Published by Elsevier Ltd.
Tsao, Hsuan-Ming; Lin, Yenn-Jiang; Yun, Chun-Ho; Lai, Yau-Huei; Chang, Shih-Lin; Lo, Li-Wei; Hu, Yu-Feng; Tuan, Ta-Chuan; Chang, Hung-Yu; Kuo, Jen-Yuan; Yeh, Hung-I; Wu, Tsu-Juey; Hsieh, Ming-Hsiung; Yu, Wen-Chung; Chen, Shih-Ann
Objectives Epicardial fat was closely related to atrial fibrillation (AF). Transthoracic echocardiography (TTE) has been proposed to be a convenient imaging tool in assessing epicardial adipose tissue (EAT). The goal of the present study was to investigate whether the EAT thickness measured on TTE was a useful parameter in predicting procedural outcomes of AF ablations. Methods and Results A total of 227 paroxysmal AF (PAF) and 56 non-paroxysmal AF (non-PAF) patients receiving catheter ablations from 2008-2010 were enrolled. Echocardiography-derived regional EAT thickness from parasternal long-axis view was quantified for each patient. Free of recurrence was defined as the absence of atrial arrhythmias without using antiarrhythmic agents after ablations. The mean EAT thickness of the study population was 6.1 ± 0.8 mm. Non-PAF patients had a thicker EAT than that of PAF patients (7.0 ± 0.7 mm versus 5.9 ± 0.7 mm, p value <0.001). During the follow-up of 16 ± 9 months, there were 95 patients (33.6%) suffering from recurrences of atrial arrhythmias. Non-PAF, chads2 score, left atrial diameter and EAT thickness were independent predictors of recurrence after catheter ablations. At a cutoff value of 6 mm for PAF and 6.9 mm for non-PAF, the measurement of EAT thickness could help us to identify patients at risk of recurrences. Conclusions EAT thickness may serve as a useful parameter in predicting recurrences after AF ablations. Compared to other imaging modalities, TTE can be an alternative choice with less cost and time in assessing the effects of EAT on ablation outcomes. PMID:24066158
Lau, Chu-Pak; Wang, Chun-Chieh; Ngarmukos, Tachapong; Kim, You-Ho; Kong, Chi-Woon; Omar, Razali; Sriratanasathavorn, Charn; Munawar, Muhammad; Kam, Ruth; Lee, Kathy Lf; Lau, Elizabeth Oi-Yan; Tse, Hung-Fat
The Septal Pacing for Atrial Fibrillation Suppression Evaluation (SAFE) study is a single-blinded, parallel randomized designed multicenter study in pacemaker indicated patients with paroxysmal atrial fibrillation (AF). The objective is to evaluate whether the site of atrial pacing--conventional right atrial appendage versus low atrial septal--with or without atrial overdrive pacing will influence the development of persistent AF. The study will provide a definitive answer to whether a different atrial pacing site or the use of AF suppression pacing or both can give incremental antiarrhythmic benefit when one is implanting a device for a patient with a history of paroxysmal AF.
Mateos, José Carlos Pachón; Mateos, Enrique I Pachón; Lobo, Tasso J; Pachón, Maria Zélia C; Mateos, Juán Carlos Pachón; Pachón, Denilda Queiroz V; Vargas, Remy Nelson A; Piegas, Leopoldo S; Jatene, Adib D
Two types of myocardia can be observed through the endocardial spectral mapping (SM) in sinus rhythm: the compact type with a smooth spectrum and the fibrillar type with a segmented spectrum (atrial fibrillation nests). During the atrial fibrillation (AF), the compact type has an organized activation and low frequency (passive), whereas the fibrillar type has a rather disorganized activation and high frequency (active/resonant), with both being activated by high-frequency sustained tachycardia--the background tachycardia (BT). To describe the treatment of AF by the ablation of the AF nests and BT. 1) Catheter ablation of the AF nests with RF [4/8 mm-60 masculine/30-40 J/30s] guided by SM in sinus rhythm, outside the pulmonary vein; 2) atrial stimulation -300 ppm; 3) Additional ablation of the AF nests if AF is induced; 4) Focal ablation if BT and/or Flutter is induced; 5) Clinical follow-up+ ECG+ Holter. A total of 50+/-18 AF nests/patient were treated. After 11.3+/-8 m, 81 patients (88%) did not present AF (28.3% with antiarrhythmic drugs). After the ablation of the AF nests, AF was not reinduced in 61 patients (71%) and BT was induced and treated in 24 patients (26%). There were two episodes of pericardial bleeding (1 treated clinically and 1 surgically), caused by sheaths that are no longer used The SM in sinus rhythm can be used in the ablation of AF nests. During the AF, the AF nests present a reactive-resonant pattern and the compact myocardium is passive, stimulated by the high frequency of the BT. After the ablation of the AF nests and the BT, it was not possible to reinduce the sustained AF. The Ablation of AF nests outside the pulmonary veins showed to be safe and highly effective in the cure and/or clinical control of the AF.
García, Manuel; Ródenas, Juan; Alcaraz, Raúl; Rieta, José J
Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and a growing healthcare burden worldwide. It is often asymptomatic and may appear as episodes of very short duration; hence, the development of methods for its automatic detection is a challenging requirement to achieve early diagnosis and treatment strategies. The present work introduces a novel method exploiting the relative wavelet energy (RWE) to automatically detect AF episodes of a wide variety in length. The proposed method analyzes the atrial activity of the surface electrocardiogram (ECG), i.e., the TQ interval, thus being independent on the ventricular activity. To improve its performance under noisy recordings, signal averaging techniques were applied. The method's performance has been tested with synthesized recordings under different AF variable conditions, such as the heart rate, its variability, the atrial activity amplitude or the presence of noise. Next, the method was tested with real ECG recordings. Results proved that the RWE provided a robust automatic detection of AF under wide ranges of heart rates, atrial activity amplitudes as well as noisy recordings. Moreover, the method's detection delay proved to be shorter than most of previous works. A trade-off between detection delay and noise robustness was reached by averaging 15 TQ intervals. Under these conditions, AF was detected in less than 7 beats, with an accuracy higher than 90%, which is comparable to previous works. Unlike most of previous works, which were mainly based on quantifying the irregular ventricular response during AF, the proposed metric presents two major advantages. First, it can perform successfully even under heart rates with no variability. Second, it consists of a single metric, thus turning its clinical interpretation and real-time implementation easier than previous methods requiring combined indices under complex classifiers. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Sacher, Frédéric; Monahan, Kristi H; Thomas, Stuart P; Davidson, Neil; Adragao, Pedro; Sanders, Prashanthan; Hocini, Mélèze; Takahashi, Yoshihide; Rotter, Martin; Rostock, Thomas; Hsu, Li-Fern; Clémenty, Jacques; Haïssaguerre, Michel; Ross, David L; Packer, Douglas L; Jaïs, Pierre
The purpose of this study was to characterize the occurrence of phrenic nerve injury (PNI) and its outcome after radiofrequency (RF) ablation of atrial fibrillation (AF). It is recognized that extra-myocardial damage may develop owing to penetration of ablative energy. Between 1997 and 2004, 3,755 consecutive patients underwent AF ablation at five centers. Among them, 18 patients (0.48%; 9 male, 54 +/- 10 years) had PNI (16 right, 2 left). The procedure consisted of pulmonary vein (PV) isolation in 15 patients and anatomic circumferential ablation in 3 patients, with additional left atrial lesions (n = 11) and/or superior vena cava (SVC) disconnection (n = 4). Right PNI occurred during ablation of right superior PV (n = 12) or SVC disconnection (n = 3). Left PNI occurred during ablation at the left atrial appendage. Immediate features were dyspnea, cough, hiccup, and/or sudden diaphragmatic elevation in 9, and in the remaining the diagnosis was made after ablation owing to dyspnea (n = 7) or on routine radiographic evaluation (n = 2). Four patients (22%) were asymptomatic. Complete recovery occurred in 12 patients (66%). Recovery occurred within 24 h in the two patients with left PNI and in one patient with right PNI occurring with SVC disconnection. In the other nine patients, right PNI recovery occurred after 4 +/- 5 months (1 to 12 months) with respiratory rehabilitation. After a mean follow-up of 36 +/- 33 months, six patients have persistent PNI (three with partial and three with no recovery). In this multicenter experience, PNI was a rare complication (0.48%) of AF ablation. Ablation of the right superior PV, SVC, and left atrial appendage were associated with PNI. Complete (66%) or partial (17%) recovery was observed in the majority.
Impact of Complete Versus Incomplete Circumferential Lines Around the Pulmonary Veins During Catheter Ablation of Paroxysmal Atrial Fibrillation: Results From the Gap-Atrial Fibrillation-German Atrial Fibrillation Competence Network 1 Trial.
Kuck, Karl-Heinz; Hoffmann, Boris A; Ernst, Sabine; Wegscheider, Karl; Treszl, Andras; Metzner, Andreas; Eckardt, Lars; Lewalter, Thorsten; Breithardt, Günter; Willems, Stephan
Ablation of atrial fibrillation (AF) is an established treatment option for symptomatic patients. It is not known whether complete pulmonary vein isolation (PVI) is superior to incomplete PVI with regard to the patients' clinical outcome. Patients with drug-refractory, symptomatic paroxysmal AF were randomly assigned to either incomplete (group A) or complete PVI (group B). In group A, a persistent gap was intentionally left within the circumferential ablation line, whereas in group B, complete PVI without any gaps was intended. At 3 months, all patients underwent invasive reevaluation to assess the rate of persistent PVI. Clinical follow-up was based on daily 30-s transtelephonic ECG transmissions. Primary study end point was the time to first recurrence of (symptomatic or asymptomatic) AF. A total of 233 patients were enrolled (116 in group A and 117 in group B). AF recurrence within 3 months was observed in a total of 161 patients (136 [84.5%] with symptomatic and 25 [15.5%] with asymptomatic AF); AF recurred in 62.2% of group B patients and 79.2% of group A patients (P<0.001), for a difference in favor of complete PVI of 17.1% (95% confidence interval, 5.3%-28.9%). Invasive restudy in 103 group A patients and 93 group B patients revealed conduction gaps in 92 (89.3%) and 65 (69.9%) patients, respectively. This study proves the superiority of complete PVI over incomplete PVI with respect to AF recurrence within 3 months. However, the rate of electric reconduction 3 months after PVI is high in patients with initially isolated PVs. URL: http://clinicaltrials.gov; Unique identifier: NCT00293943. © 2016 American Heart Association, Inc.
Granger, Christopher B; Alexander, John H; McMurray, John J V; Lopes, Renato D; Hylek, Elaine M; Hanna, Michael; Al-Khalidi, Hussein R; Ansell, Jack; Atar, Dan; Avezum, Alvaro; Bahit, M Cecilia; Diaz, Rafael; Easton, J Donald; Ezekowitz, Justin A; Flaker, Greg; Garcia, David; Geraldes, Margarida; Gersh, Bernard J; Golitsyn, Sergey; Goto, Shinya; Hermosillo, Antonio G; Hohnloser, Stefan H; Horowitz, John; Mohan, Puneet; Jansky, Petr; Lewis, Basil S; Lopez-Sendon, Jose Luis; Pais, Prem; Parkhomenko, Alexander; Verheugt, Freek W A; Zhu, Jun; Wallentin, Lars
Vitamin K antagonists are highly effective in preventing stroke in patients with atrial fibrillation but have several limitations. Apixaban is a novel oral direct factor Xa inhibitor that has been shown to reduce the risk of stroke in a similar population in comparison with aspirin. In this randomized, double-blind trial, we compared apixaban (at a dose of 5 mg twice daily) with warfarin (target international normalized ratio, 2.0 to 3.0) in 18,201 patients with atrial fibrillation and at least one additional risk factor for stroke. The primary outcome was ischemic or hemorrhagic stroke or systemic embolism. The trial was designed to test for noninferiority, with key secondary objectives of testing for superiority with respect to the primary outcome and to the rates of major bleeding and death from any cause. The median duration of follow-up was 1.8 years. The rate of the primary outcome was 1.27% per year in the apixaban group, as compared with 1.60% per year in the warfarin group (hazard ratio with apixaban, 0.79; 95% confidence interval [CI], 0.66 to 0.95; P<0.001 for noninferiority; P=0.01 for superiority). The rate of major bleeding was 2.13% per year in the apixaban group, as compared with 3.09% per year in the warfarin group (hazard ratio, 0.69; 95% CI, 0.60 to 0.80; P<0.001), and the rates of death from any cause were 3.52% and 3.94%, respectively (hazard ratio, 0.89; 95% CI, 0.80 to 0.99; P=0.047). The rate of hemorrhagic stroke was 0.24% per year in the apixaban group, as compared with 0.47% per year in the warfarin group (hazard ratio, 0.51; 95% CI, 0.35 to 0.75; P<0.001), and the rate of ischemic or uncertain type of stroke was 0.97% per year in the apixaban group and 1.05% per year in the warfarin group (hazard ratio, 0.92; 95% CI, 0.74 to 1.13; P=0.42). In patients with atrial fibrillation, apixaban was superior to warfarin in preventing stroke or systemic embolism, caused less bleeding, and resulted in lower mortality. (Funded by Bristol-Myers Squibb
Connolly, Stuart J; Ezekowitz, Michael D; Yusuf, Salim; Eikelboom, John; Oldgren, Jonas; Parekh, Amit; Pogue, Janice; Reilly, Paul A; Themeles, Ellison; Varrone, Jeanne; Wang, Susan; Alings, Marco; Xavier, Denis; Zhu, Jun; Diaz, Rafael; Lewis, Basil S; Darius, Harald; Diener, Hans-Christoph; Joyner, Campbell D; Wallentin, Lars
Warfarin reduces the risk of stroke in patients with atrial fibrillation but increases the risk of hemorrhage and is difficult to use. Dabigatran is a new oral direct thrombin inhibitor. In this noninferiority trial, we randomly assigned 18,113 patients who had atrial fibrillation and a risk of stroke to receive, in a blinded fashion, fixed doses of dabigatran--110 mg or 150 mg twice daily--or, in an unblinded fashion, adjusted-dose warfarin. The median duration of the follow-up period was 2.0 years. The primary outcome was stroke or systemic embolism. Rates of the primary outcome were 1.69% per year in the warfarin group, as compared with 1.53% per year in the group that received 110 mg of dabigatran (relative risk with dabigatran, 0.91; 95% confidence interval [CI], 0.74 to 1.11; P<0.001 for noninferiority) and 1.11% per year in the group that received 150 mg of dabigatran (relative risk, 0.66; 95% CI, 0.53 to 0.82; P<0.001 for superiority). The rate of major bleeding was 3.36% per year in the warfarin group, as compared with 2.71% per year in the group receiving 110 mg of dabigatran (P=0.003) and 3.11% per year in the group receiving 150 mg of dabigatran (P=0.31). The rate of hemorrhagic stroke was 0.38% per year in the warfarin group, as compared with 0.12% per year with 110 mg of dabigatran (P<0.001) and 0.10% per year with 150 mg of dabigatran (P<0.001). The mortality rate was 4.13% per year in the warfarin group, as compared with 3.75% per year with 110 mg of dabigatran (P=0.13) and 3.64% per year with 150 mg of dabigatran (P=0.051). In patients with atrial fibrillation, dabigatran given at a dose of 110 mg was associated with rates of stroke and systemic embolism that were similar to those associated with warfarin, as well as lower rates of major hemorrhage. Dabigatran administered at a dose of 150 mg, as compared with warfarin, was associated with lower rates of stroke and systemic embolism but similar rates of major hemorrhage. (ClinicalTrials.gov number
Biviano, Angelo B.; Ciaccio, Edward J.; Fleitman, Jessica; Knotts, Robert; Lawrence, John; Haynes, Norrisa; Cyrille, Nicole; Hickey, Kathleen; Iyer, Vivek; Wan, Elaine; Whang, William; Garan, Hasan
INTRODUCTON Atrial fibrillation (AF) ablation patients often manifest atrial tachycardias (AT) with atypical ECG morphologies that preclude accurate localization and mechanism. Diagnostic maneuvers used to define ATs during electrophysiology studies can be limited by tachycardia termination or transformation. Additional methods of characterizing post-AF ablation ATs are required. METHODS AND RESULTS We evaluated the utility of noninvasive ECG signal analytics in post-ablation AF patients for the following features: 1) Localization of ATs (i.e., right versus left atrium), and 2) Identification of common left AT mechanisms (i.e., focal vs. macroreentrant). Atrial waveforms from the surface ECG were used to analyze: 1) Spectral organization, including dominant amplitude (DA) and mean spectral profile (MP), and 2) Temporospatial variability, using temporospatial correlation coefficients. We studied 94 ATs in 71 patients who had undergone prior pulmonary vein isolation for AF and returned for a second ablation: 1) right atrial cavotricuspid-isthmus dependent (CTI) ATs (n=21); 2) left atrial macroreentrant ATs (n=41) and focal ATs (n=32). Right CTI ATs manifested higher DAs and lower MPs than left ATs, indicative of greater stability and less complexity in the frequency spectrum. Left macroreentrant ATs possessed higher temporospatial organization than left focal ATs. CONCLUSIONS Noninvasively recorded atrial waveform signal analyses show that right ATs possess more stable activation properties than left ATs, and left macroreentrant ATs manifest higher temporospatial organization than left focal ATs. Further prospective analyses evaluating the role these novel ECG-derived tools can play to help localize and identify mechanisms of common ATs in AF ablation patients are warranted. PMID:26228873
Xi, Yutao; Chao, Zhi-Yang James; Yan, Wen; Abbasi, Shahrzad; Yin, Xiaomeng; Mathuria, Nilesh; Patel, Mehul; Fan, Christopher; Sun, Junping; Wu, Geru; Wang, Suwei; Elayda, MacArthur; Gao, Lianjun; Wehrens, Xander H.T.; Lin, Shien-Fong; Cheng, Jie
BACKGROUND Vagal hyperactivity promotes atrial fibrillation (AF), which has been almost exclusively attributed to acetylcholine. Vasoactive intestinal polypeptide (VIP) and acetylcholine are neurotransmitters co-released during vagal stimulation. Exogenous VIP has been shown to promote AF by shortening action potential duration (APD), increasing APD spatial heterogeneity, and causing intra-atrial conduction block. OBJECTIVE The purpose of this study was to investigate the effects of neuronally released VIP on atrial electrophysiologic properties during vagal stimulation. METHODS We used a specific VIP antagonist (H9935) to uncover the effects of endogenous VIP released during vagal stimulation in canine hearts. RESULTS H9935 significantly attenuated (1) the vagally induced shortening of atrial effective refractory period and widening of atrial vulnerability window during stimulation of cervical vagosym-pathetic trunks (VCNS) and (2) vagal effects on APD during stimulation through fat-pad ganglion plexus (VGPS). Atropine completely abolished these vagal effects during VCNS and VGPS. In contrast, VGPS-induced slowing of local conduction velocity was completely abolished by either VIP antagonist or atropine. In pacing-induced AF during VGPS, maximal dominant frequencies and their spatial gradients were reduced significantly by H9935 and, more pronouncedly, by atropine. Furthermore, VIP release in the atria during vagal stimulation was inhibited by atropine, which may account for the concealment of VIP effects with muscarinic blockade. CONCLUSION Neuronally released VIP contributes to vagal effects on atrial electrophysiologic properties and affects the pathophysiology of vagally induced AF. Neuronal release of VIP in the atria is inhibited by muscarinic blockade, a novel mechanism by which VIP effects are concealed by atropine during vagal stimulation. PMID:25748673
Smorodinova, Natalia; Bláha, Martin; Melenovský, Vojtěch; Rozsívalová, Karolína; Přidal, Jaromír; Ďurišová, Mária; Pirk, Jan; Kautzner, Josef; Kučera, Tomáš
Background Atrial fibrillation (AF) is the most common arrhythmia and despite obvious clinical importance remains its pathogenesis only partially explained. A relation between inflammation and AF has been suggested by findings of increased inflammatory markers in AF patients. Objective The goal of this study was to characterize morphologically and functionally CD45-positive inflammatory cell populations in atrial myocardium of patients with AF as compared to sinus rhythm (SR). Methods We examined 46 subjects (19 with AF, and 27 in SR) undergoing coronary bypass or valve surgery. Peroperative bioptic samples of the left and the right atrial tissue were examined using immunohistochemistry. Results The number of CD3+ T-lymphocytes and CD68-KP1+ cells were elevated in the left atrial myocardium of patients with AF compared to those in SR. Immune cell infiltration of LA was related to the rhythm, but not to age, body size, LA size, mitral regurgitation grade, type of surgery, systemic markers of inflammation or presence of diabetes or hypertension. Most of CD68-KP1+ cells corresponded to dendritic cell population based on their morphology and immunoreactivity for DC-SIGN. The numbers of mast cells and CD20+ B-lymphocytes did not differ between AF and SR patients. No foci of inflammation were detected in any sample. Conclusions An immunohistochemical analysis of samples from patients undergoing open heart surgery showed moderate and site-specific increase of inflammatory cells in the atrial myocardium of patients with AF compared to those in SR, with prevailing population of monocyte-macrophage lineage. These cells and their cytokine products may play a role in atrial remodeling and AF persistence. PMID:28225836
Ricci, R P; Russo, M; Santini, M
A large number of patients implanted with dual-chamber pacemakers exhibit symptoms of recurrent or new atrial fibrillation. Scheduling follow-up visits for every 6-12 months in this setting may be disadvantageous on three grounds. First, delayed information about the onset of atrial fibrillation does not allow an immediate reaction with pharmacological or dedicated pacing therapy. Second, the efficacy of the chosen therapy cannot be evaluated until the next scheduled follow-up. Third, real-time awareness of a significant atrial fibrillation burden is critical to use appropriate anticoagulation therapy for the prevention of thromboembolic events. The new Home Monitoring technology (Biotronik, Berlin) offers real-time transmission of diagnostic data stored in the pacemaker memory to the physician. This may represent a useful tool for the detection and treatment of patients with atrial fibrillation. Daily documentation of atrial rhythm via Home Monitoring allows a quick reaction to the onset of atrial fibrillation and real-time control of the therapeutic efficacy. The ongoing, international, randomized Home-PAT clinical trial aims at defining and quantifying the importance of Home Monitoring for the diagnosis and treatment of atrial fibrillation in patients with dual-chamber pacemakers.
Wagdi, Philipp; Salzer, Frank
Life expectancy of the population is steadily increasing world wide. Consequently, the incidence and ultimately the prevalence of atrial fibrillation (AF) and it’s sequelae will be rising proportionately. It is estimated that 3-5% of persons above 65 years of age have chronic AF, 30% of which will suffer at least one stroke. On the other hand, chronic AF is responsible for about 20% of all cerebrovascular accidents. Predictors of stroke in AF have been defined by the CHADS2 score, and in these patients, oral anticoagulation has been the cornerstone of thromboembolic disease prevention. Because elderly patients have an increased risk of bleeding complications even under the newer antagonists of Factor Xa and direct Thrombin inhibitors, percutaneous occlusion of the left atrial appendage (LAA) as the main thrombogenic source offers an attractive alternative to permanent anticoagulation. This promising new therapeutic approach is put into clinical real world perspective.
Contractor, Tahmeed; Khasnis, Atul
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.
Moss, Joshua D
Stroke prevention is of vital importance in the management of atrial fibrillation (AF), though the proven strategy of systemic anticoagulation for thromboembolic prophylaxis is underutilized for a variety of reasons. The left atrial appendage (LAA) has long been suspected as the principal source of arterial emboli, particularly in nonvalvular AF, and a variety of techniques for its exclusion from the circulation have been developed. This review highlights the history of the LAA as a target of intervention, and the parallel advances in three minimally invasive strategies for its exclusion: percutaneous occlusion of the LAA orifice from within the left atrium, closed-chest ligation via a percutaneous pericardial approach, and minimally invasive thoracoscopic surgery. While further study is necessary, available evidence suggests that effective LAA exclusion is becoming a viable alternative to anticoagulation for stroke prevention in nonvalvular AF.
Price, Matthew J
Atrial fibrillation (AF) is a major cause of stroke and systemic embolism. Although warfarin and the novel oral anticoagulants reduce thromboembolic risk, they are associated with an ongoing bleeding hazard, in addition to other limitations that deter their use. The left atrial appendage (LAA) appears to be the primary source of thrombus in AF; therefore, LAA closure represents a mechanical strategy for stroke prevention in these patients. The WATCHMAN™ LAA closure device (Boston Scientific, Natick, MA) is a nitinol-framed occluder that is implanted percutaneously under echocardiographic and fluoroscopic guidance. Data from two randomized clinical trials support the clinical efficacy of transcatheter LAA occlusion with the WATCHMAN and demonstrate that procedural safety has improved significantly since initial experience. This article summarizes the rationale, procedural technique, safety, and clinical efficacy of the WATCHMAN device in patients with AF at high risk for thromboembolic events.
Sánchez, Carlos; Bueno-Orovio, Alfonso; Wettwer, Erich; Loose, Simone; Simon, Jana; Ravens, Ursula; Pueyo, Esther; Rodriguez, Blanca
Aims Human atrial electrophysiology exhibits high inter-subject variability in both sinus rhythm (SR) and chronic atrial fibrillation (cAF) patients. Variability is however rarely investigated in experimental and theoretical electrophysiological studies, thus hampering the understanding of its underlying causes but also its implications in explaining differences in the response to disease and treatment. In our study, we aim at investigating the ability of populations of human atrial cell models to capture the inter-subject variability in action potential (AP) recorded in 363 patients both under SR and cAF conditions. Methods and Results Human AP recordings in atrial trabeculae (n = 469) from SR and cAF patients were used to calibrate populations of computational SR and cAF atrial AP models. Three populations of over 2000 sampled models were generated, based on three different human atrial AP models. Experimental calibration selected populations of AP models yielding AP with morphology and duration in range with experimental recordings. Populations using the three original models can mimic variability in experimental AP in both SR and cAF, with median conductance values in SR for most ionic currents deviating less than 30% from their original peak values. All cAF populations show similar variations in GK1, GKur and Gto, consistent with AF-related remodeling as reported in experiments. In all SR and cAF model populations, inter-subject variability in IK1 and INaK underlies variability in APD90, variability in IKur, ICaL and INaK modulates variability in APD50 and combined variability in Ito and IKur determines variability in APD20. The large variability in human atrial AP triangulation is mostly determined by IK1 and either INaK or INaCa depending on the model. Conclusion Experimentally-calibrated human atrial AP models populations mimic AP variability in SR and cAF patient recordings, and identify potential ionic determinants of inter-subject variability in
De Simone, Antonio; Senatore, Gaetano; Donnici, Giovanni; Turco, Pietro; Romano, Enrico; Gazzola, Carlo; Stabile, G
The impact of new algorithms to consistently pace the atrium on the prevention of atrial fibrillation (AF) remains unclear. Our randomized, crossover study compared the efficacy of single- and dual-site atrial pacing, with versus without dynamic atrial overdrive pacing in preventing AF. We studied 72 patients (mean age = 69.6 +/- 6.5 years, 34 men) with sick sinus syndrome (SSS) and paroxysmal or persistent AF, who received dual-chamber pacemakers (PM) equipped with an AF prevention algorithm and two atrial leads placed in the right atrial appendage (RAA), by passive fixation, and in the coronary sinus ostium (CS), by active fixation, respectively. At implant, the patients were randomly assigned to unipolar CS versus RAA pacing. The PM was programmed in DDDR mode 1 month after implant. Each patient underwent four study phases of equal duration: (1) unipolar, single site (CS or RAA) pacing with the AF algorithm ON (atrial lower rate = 0 ppm); (2) unipolar, single site pacing with the AF algorithm OFF (atrial lower rate = 70 bpm); (3) bipolar, dual-site pacing with AF algorithm ON; (4) bipolar, dual-site pacing with the AF algorithm OFF. Among 40 patients (56%), who completed the follow-up (15 +/- 4 months) no difference was observed in the mean number of automatic mode switch (AMS) corrected for the duration of follow-up, in unipolar (5.6 +/- 22.8 vs 2.6 +/- 5.5) or bipolar mode (3.3 +/- 12.7 vs 2.1 +/- 4.9) with, respectively, the algorithm OFF or ON. With the AF prevention algorithm ON, the percentage of atrial pacing increased significantly from 78.7 +/- 22.1% to 92.4 +/- 4.9% (P < 0.001), while the average ventricular heart rate was significantly lower with the algorithm ON (62.4 +/- 17.5 vs 79.9 +/- 3 bpm (P < 0.001). The AF prevention algorithm increased the percentage of atrial pacing significantly, regardless of the atrial pulse configuration and pacing site, while maintaining a slower ventricular heart rate. It had no impact on the number of AMS in the
Rao, Meena P.; Pokorney, Sean D.; Granger, Christopher B.
Atrial fibrillation is the most common arrhythmia and accounts for one-third of hospitalizations for rhythm disorders in the United States. The prevalence of atrial fibrillation averages 1% and increases with age. With the aging of the population, the number of patients with atrial fibrillation is expected to increase 150% by 2050, with more than 50% of atrial fibrillation patients being over the age of 80. This increasing burden of atrial fibrillation will lead to a higher incidence of stroke, as patients with atrial fibrillation have a five- to sevenfold greater risk of stroke than the general population. Strokes secondary to atrial fibrillation have a worse prognosis than in patients without atrial fibrillation. Vitamin K antagonists (e.g., warfarin), direct thrombin inhibitors (dabigatran), and factor Xa inhibitors (rivaroxaban and apixaban) are all oral anticoagulants that have been FDA approved for the prevention of stroke in atrial fibrillation. This review will summarize the experience of anticoagulants in patients with atrial fibrillation with a focus on the experience at the Duke Clinic Research Institute. PMID:25215263
Onalan, Orhan; Crystal, Eugene
The efficacy of oral anticoagulation (OAC) for stroke prevention in patients with nonrheumatic atrial fibrillation (AF) has clearly been established. However, a substantial number of patients with AF who are at high risk for thromboembolic events are not candidates for long-term OAC. The left atrial appendix (LAA) is the most common place of thrombosis in patients with AF, and it can easily be excluded from the systemic circulation at the time of cardiac surgery by excision, ligation, suturing, or stapling. Currently, removal of the LAA at the time of mitral valve surgery is recommended to reduce future stroke risk. The ongoing LAA Occlusion Study (LAAOS) is evaluating the efficacy of the routine LAA occlusion in patients undergoing elective coronary artery bypass graft surgery. Recently, two devices specifically designed for percutaneous transcatheter LAA occlusion have been introduced: the Percutaneous LAA Transcatheter Occlusion (PLAATO; Appriva Medical Inc) and WATCHMAN LAA system (Atritech, Inc). More than 200 PLAATO devices were implanted worldwide in patients with nonrheumatic AF who were at high risk for ischemic stroke and not candidates for long-term OAC. In a follow-up time of 258 patient-years, an estimated 61% reduction in stroke risk was achieved with PLAATO procedure. The WATCHMAN Left Atrial Appendage System for Embolic PROTECTion in Patients With Atrial Fibrillation (PROTECT AF) study was designed to demonstrate the safety and efficacy of the WATCHMAN device in patients with nonvalvular AF who are eligible for long-term OAC. The trial is assessing whether the treatment arm (WATCHMAN device) is noninferior to the control arm (warfarin). Although present results suggest that LAA occlusion may reduce the long-term stroke risk, available data are still very limited. At present, percutaneous LAA occlusion may be an acceptable option in selected high-risk patients with AF who are not candidates for OAC. The current understanding of LAA exclusion for the
Rolf, Sascha; Sommer, Philipp; Gaspar, Thomas; John, Silke; Arya, Arash; Hindricks, Gerhard; Piorkowski, Christopher
We describe a novel fluoroscopy coregistered, 4-dimensional catheter tracking technology (MediGuide Technology [MGT]) used for treatment of patients with atrial fibrillation. The aim of the study was to investigate (1) the feasibility of nonfluoroscopic catheter manipulation within dynamic left atrial chamber models; (2) the integration of the technology into an established electroanatomical mapping system; and (3) potential clinical impact. Forty-nine patients received atrial fibrillation ablation using MGT-enabled NavX-EnSite. Matched patients ablated with a conventional NavX-EnSite system served as a control group. MGT was used for the deployment of diagnostic catheters within preacquired cine loops, for nonfluoroscopic chamber mapping within dynamic angiograms, and for 4-dimensional tagging of anatomical landmarks. Integration with the electroanatomical mapping system allowed correction of field distortions and a reference tool to detect and correct map shifts. Catheter ablation was done without MGT because the ablation catheter was not MGT enabled. MGT worked safely and stably in all 49 patients. Catheter deployment within the preacquired cine loops was successfully performed in 45 of 49 (92%) patients. Catheter tracking within dynamic left atrial angiograms allowed nearly nonfluoroscopic creation of NavX-EnSite geometries with subsequent computed tomography model registration in all 49 patients. Overall, MGT significantly reduced total procedural fluoroscopy time (median [quartiles]) from 31 minutes (25, 43 minutes) to 16 minutes (10, 23 minutes) and irradiation dose from 14 453±7403 to 7363±5827 cGy*cm(2) (mean±SD), respectively (P<0.001). MGT is a tracking technology that allows 4-dimensional visualization of dedicated catheters within moving chamber models. Integration of the MGT with an established electroanatomical mapping system provided algorithms to facilitate mapping in the electroanatomical mapping system environment. As a first measurable
Sun, Juan; Lu, Yanmei; Wugeti, Najina; Aikemu, Ainiwaer
Background: This study sought to examine the effect of the cardiac autonomic nerve plexus, which originates from the vagus nerve trunk, on atrial vulnerability. Methods: Dogs in group I (n = 6) underwent ganglionated plexi (GP) sequential ablation following six hours of left atrial appendage rapid atrial pacing (RAP). The monophasic action potential duration at 90% of repolarization (APD90), effective refractory period (ERP), and the atrial fibrillation inducing rate of bilateral atria and pulmonary veins were recorded at baseline, l h, 3 h and 6 h after pacing, as well as after sequential ablation (RAGP + RIGP ablation, LSGP + RIGP ablation). Dogs in group II (n = 6) received vagus nerve stimulation following six hours of left atrial appendage RAP. APD90, ERP and atrial fibrillation inducing rate of bilateral atria and pulmonary veins were recorded at baseline, 1 h, 3 h and 6 h after pacing, as well as after GP sequential ablation (RAGP + RIGP ablation, LSGP + RIGP ablation). Results: In group I, APD90 and ERP progressively shortened and atrial fibrillation inducing rate increased in various sites l h, 3 h and 6 h after RAP (P < 0.05). APD90 and ERP shortened significantly and atrial fibrillation inducing rate was significantly higher in the left atrial appendage and bilateral pulmonary veins than in other sites (P < 0.05). Following GP sequential ablation, APD90, ERP and atrial fibrillation inducing rate were not significantly different from baseline levels (P > 0.05). In group II, APD90 and ERP progressively shortened in various sites over pacing time period, and the atrial fibrillation inducing rate increased l h, 3 h and 6 h after RAP + VNS (P < 0.05). APD90 and ERP shortened significantly and atrial fibrillation inducing rate was significantly higher in the left atrial appendage and right superior/inferior pulmonary veins when compared with other sites (P < 0.05). After GP sequential ablation, APD90, ERP and atrial fibrillation inducing rate were not
Aksu, Tolga; Güler, Tümer Erdem; Mutluer, Ferit Onur; Oto, Mehmet Ali
Although pulmonary vein isolation is accepted as an established interventional treatment in paroxysmal atrial fibrillation (AF), alternative modalities are being investigated because of the high recurrence rates of nonparoxysmal forms. One of the alternative ablation approaches is ablation or modification of vagal ganglionated plexi (VGP). The technique has not only been used in vagally mediated AF but also investigated in paroxysmal and nonparoxysmal AF. Clinical studies demonstrate significant discrepancy related with detection of VGP sites or ablation targets and definition of procedurel end-points, so far. In this review, we aimed to discuss the current data on the role of VGP in the pathogenesis of AF and potential therapeutic implications of ablation of these ganglia.
Expósito, Víctor; Seras, Miguel; Fernández-Fresnedo, Gema
Atrial fibrillation is a common finding in patients with chronic kidney disease (CKD), which increases markedly the embolism risk. The CHADS2 and HAS-BLED scales, used in the general population to assess the risk/benefit of oral anticoagulation (OAC), underestimate respectively the risk of embolism and haemorrhage in CKD, making it difficult to decide whether to use OAC or not. Based on the available evidence, it seems indicated to use OAC in stage 3 CKD, while it is controversial in advanced stages. New OAC such as dabigatran and rivaroxaban have been approved in stage 3 CKD but their role is still somewhat uncertain. Copyright © 2013 Elsevier España, S.L.U. All rights reserved.
Capranzano, Piera; Miccichè, Eligio; D'Urso, Lucia; Privitera, Fiorella; Tamburino, Corrado
For decades, warfarin has remained the standard oral anticoagulation for stroke prevention in atrial fibrillation (AF). Three novel oral anticoagulants (NOACs) have been recently approved for stroke prevention in non-valvular AF: dabigatran, rivaroxaban and apixaban. Better pharmacological and clinical profiles make these newcomers a preferable alternative over warfarin. Current AF guidelines do not endorse NOACs over warfarin, or one NOAC over another. Indeed, choice of the anticoagulation regimen should be personalized based on the relative efficacy and safety of different agents across subgroups stratified by thrombotic and bleeding risk, as well as on other clinical factors, including anticoagulation control on warfarin, drug interactions, compliance and need for coagulation monitoring. This review appraises i) the randomized evidence on approved NOACs versus warfarin in AF across subgroups stratified by risk factors of stroke and bleeding and by the anticoagulation level reached on warfarin; and ii) clinical factors impacting on the anticoagulation regimen selection.
Weiner, P; Bassan, M M; Jarchovsky, J; Iusim, S; Plavnick, L
Forty-seven episodes of acute atrial fibrillation (AF) in 45 patients were examined prospectively to determine the course of the disorder treated with rapid digitalization. Patients received 1.5 mg of digoxin intravenously over 12 hours. In 40 of the 47 attacks, reversion to sinus rhythm occurred with no additional therapy at 1 to 96 hours (median 4 hours) after beginning digoxin. In thirty-two patients, conversion occurred within 8 hours; only one patient showed important ventricular slowing before conversion. Thus, if digoxin facilitates conversion, it does not do so by slowing the ventricular response. Of the 11 patients still in AF at 16 hours, conversion subsequently occurred in only four who were receiving digoxin alone. We conclude that the prognosis for quick reversion to sinus rhythm in patients with acute AF treated with rapid digitalization alone is excellent. If reversion does not occur by 16 to 24 hours, additional measures to restore sinus rhythm are indicated.
Dahlberg, Katherine Willett
Abstract: Despite the availability of predictive tools and treatment guidelines, anticoagulant therapies are underprescribed and many patients are undertreated for conditions that predispose to thromboembolic complications, including stroke. This review explores reasons for which physicians fear that the risks of anticoagulation may be greater than the potential benefit. The results of numerous clinical trials confirm that patients benefit from judiciously managed anticoagulation and that physicians can take various approaches to minimize risk. Use of stratification scores for patient selection and accurate estimation of stroke risk may improve outcomes; bleeding risk is less important than stroke risk. Adoption of newer anticoagulants with simpler regimens may help physicians allay their fears of anticoagulant use in patients with atrial fibrillation. These fears, although not groundless, should not overtake caution and hinder the delivery of appropriate evidence-based care. PMID:25285512
Edholm, Karli; Ragle, Nathan; Rondina, Matthew T.
SYNOPSIS Compared to younger patients, older patients with atrial fibrillation (AF) have an increased risk of stroke and systemic embolism1, 2. For the majority of patients, oral anticoagulation (OAC) remains the most effective way to reduce this risk. While vitamin K antagonists (VKAs) have been used for decades, the more recent development of non-vitamin K dependent oral anticoagulants (NOACs) provides clinicians with broader selection of anticoagulants for stroke prevention in older AF patients. In this review, we discuss stroke risk-stratification tools for clinical decision making, review pharmacologic options for the prevention of stroke, and highlight several practical considerations to the use of these agents in older adults. PMID:25700592
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
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.
Suárez Fernández, C; Camafort, M; Cepeda Rodrigo, J M; Díez-Manglano, J; Formiga, F; Pose Reino, A; Tiberio, G; Mostaza, J M
Atrial fibrillation (AF) in the elderly is a complex condition due to the high number of frequently associated comorbidities, such as cardiovascular and kidney disease, cognitive disorders, falls and polypharmacy. Except when contraindicated, anticoagulation is necessary for preventing thromboembolic events in this population. Both vitamin K antagonists and direct oral anticoagulants (dabigatran, rivaroxaban and apixaban) are indicated in this context. Renal function should be closely monitored for this age group when these drugs are used. In recent years, various clinical practice guidelines have been published on patients with AF. The majority of these guidelines make specific recommendations on the clinical characteristics and treatment of elderly patients. In this update, we review the specific comments on the recommendations concerning antithrombotic treatment in elderly patients with nonvalvular AF. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Medicina Interna (SEMI). All rights reserved.
Sovari, Ali A.; Dudley, Samuel C.
Atrial fibrillation (AF) is the most common arrhythmia that requires medical attention, and its incidence is increasing. Current ion channel blockade therapies and catheter ablation have significant limitations in treatment of AF, mainly because they do not address the underlying pathophysiology of the disease. Oxidative stress has been implicated as a major underlying pathology that promotes AF; however, conventional antioxidants have not shown impressive therapeutic effects. A more careful design of antioxidant therapies and better selection of patients likely are required to treat effectively AF with antioxidant agents. Current evidence suggest inhibition of prominent cardiac sources of reactive oxygen species (ROS) such as nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and targeting subcellular compartments with the highest levels of ROS may prove to be effective therapies for AF. Increased serum markers of oxidative stress may be an important guide in selecting the AF patients who will most likely respond to antioxidant therapy. PMID:22934062
Turakhia, Mintu P; Kaiser, Daniel W
Atrial fibrillation (AF) is a multifaceted and highly variable disease that is often difficult to manage within the traditional health-care model. The conventional model of regular or pre-scheduled appointments with physicians or allied health professionals is poorly suited to the unpredictable and often urgent clinical needs of patients with AF. Mobile health (mHealth) has the potential to dramatically transform the delivery and quality of AF care. In this brief review, we summarize the current limitations and evidence gaps in treating patients with AF. We then describe the current mHealth landscape, changes in telehealth coverage and reimbursement, and recent technological advances of smartphones, mobile applications, and connected wearable devices. We also describe important barriers and challenges, such as clinical management of large volumes of data, application of predictive analytics/machine learning, and the need for high-quality randomized clinical trials.
Kyprianou, Katerina; Pericleous, Agamemnon; Stavrou, Antonio; Dimitrakaki, Inetzi A; Challoumas, Dimitrios; Dimitrakakis, Georgios
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
Shukla, Ashish; Curtis, Anne B
Atrial fibrillation (AF) is the most common sustained arrhythmia and a major global public health problem due to its associated morbidity, including stroke and heart failure, diminished quality of life, and increased mortality. AF often presents initially in a paroxysmal form and may progress to a more sustained form over time. Evidence from randomized controlled trials suggests that there may be no mortality benefit to using a rhythm control approach in comparison with rate control of AF. Nevertheless, sustained forms of AF may be associated with increased symptoms and cardiovascular morbidity, and consequently they remain an additional target for therapy. The present review evaluates the clinical correlates of arrhythmia progression and risk stratification techniques available to assess probability of AF progression. Further, currently available management options for arrhythmia control in AF are evaluated and their therapeutic effect and efficacy on disease progression are explored. PMID:24379678
Márquez, Manlio F
The present report describes the program of radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) in patients referred to the AF Clinic of the National Institute of Cardiology. Specific inclusion criteria are required for RFCA of AF. If the patient fulfills it, then an electrophysiological study is performed. A transseptal approach and special mapping catheters are used to detect abnormal electrical activity (AEA). Pulmonary vein isolation is performed at the ostium/ antrum of those veins with AEA if the patient had paroxysmal AF. Global pulmonary vein isolation with some additional lines guided by electroanatomical mapping is performed in the case of chronic AF. Postoperative follow-up includes consultation, ECG and Holter monitoring at 1, 3, 6 and 12-month. RFCA is a useful and relatively safe procedure for the treatment of AF and the only one with curative potential.
Angaran, Paul; Dorian, Paul
Atrial fibrillation (AF) is a common arrhythmia associated with significant morbidity and mortality. There has been much debate about the relative merits of rate vs rhythm control strategies, and studies to date have failed to show advantage with a rhythm-control strategy using antiarrhythmic drugs (AADs). This is likely because of the inadequacies of our current AADs and the limitations of study designs. However, there is evidence that AADs improve symptoms and quality of life (QOL). Until trials are performed with more appropriate patient selection, and end points and better AADs and strategies for their use, rhythm control should not be abandoned and may continue to be beneficial in selected patients. Copyright © 2013 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.
Galvez-Olortegui, José Kelvin; Álvarez-Vargas, Mayita Lizbeth; Galvez-Olortegui, Tomas Vladimir; Godoy-Palomino, Armando; Camacho-Saavedra, Luis
The aim of this study is the methodological evaluation of Clinical Practice Guidelines (CPG) in atrial fibrillation. This is the second in a series of articles of review, analysis, assessment in methodology and content of clinical practice guidelines in Cardiology. Among all clinical practice guidelines, we selected the American, Canadian and NICE (National Institute for Health and Care Excellence) guidelines. We used the AGREE (Appraisal of Guidelines for Research and Evaluation) II instrument for the assessment. In general, the guidelines obtained the lowest score in the applicability domain (mean 36.1%); while the highest score was for clarity of presentation (mean 93.5%). The lowest percentage was found in the editorial independence domain (Canadian guideline) and the highest of all scores in the applicability domain (NICE guideline). Regarding global quality, the NICE guideline obtained the AGREE II instrument best scores, followed by the American guideline, both recommended for use without modifications.
Adam, M; Fischetti, D; Montenero, A S
Atrial fibrillation affects a large population of patients. The electrophysiological mechanisms that initiate and maintain atrial fibrillation may be multiple. Even if some studies exploring right atrial activation have been recently published, data concerning atrial fibrillation activation patterns and its mechanisms are still scarce and controversial. This study supplies information on right atrial activation during atrial fibrillation. Twenty-four patients with recurrent, drug-refractory, lone paroxysmal atrial fibrillation underwent an extensive mapping of the right atrium. A pattern of organized atrial fibrillation (type 1) was noted in the trabeculated right atrium and atrial roof, characterized by discrete atrial electrograms, separated by an isoelectric baseline, with a continuous switching between clockwise and counterclockwise activation that we called washing-machine phenomenon. In the majority of patients, recordings from the anterior and medial areas of the atrial septum, showed fractionated electrograms consistent with a more disorganized activation pattern. Atrial activation in the inferior septum and coronary sinus was rather disorganized, neither synchronized with the activation sequence of the trabeculated right atrium nor with that of the anterior septum. Furthermore, the activation pattern showed fractionated electrograms and a variability of the isoelectric baseline similar to that recorded in the septum. No significant complications were reported during the procedure. In conclusion, mapping of the right atrium during induced atrial fibrillation shows a very typical pattern of activation in the trabeculated right atrium that we called the washing-machine phenomenon. Whether this sequence of activation represents a bystander situation or an active conditioning factor needs further investigations.
Ivanov, V P
An evaluation was carried out of variability of the heart's rhythm in 269 patients with ischemic heart disease and/or hypertensive disease, their age ranging between 43 to 82 years, complicated by frequently relapsing atrial fibrillation. It is shown that in those patients presenting with frequent recurrences of arrhythmia over the course of a 24-hour period, there comes to be a considerable decline in the power of total variability of cardiac rhythm, and all spectral components and a shift in the sympathetic/parasympathetic system balance in favour of the sympathetic one. Analyzed the study were particular features of regulation of tension of the vegetative nervous system in different clinical forms of atrial fibrillation. Patients with frequently recurring atrial fibrillation have been shown to constitute rather a miscellaneous group as to patterns of the cardiac rhythm variability, which fact is to be taken account of in conducting prophylactic antiarrhythmic therapy of recurrencies of atrial fibrillation.
Eckardt, L; Häusler, K G; Ravens, U; Borggrefe, M; Kirchhof, P
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.
Peterson, Benjamin E; Al-Khatib, Sana M; Granger, Christopher B
Atrial fibrillation is a common, costly and morbid cardiovascular arrhythmia. Stroke prevention remains the mainstay of treatment for atrial fibrillation, and the recent advent of novel oral anticoagulants with direct factor IIa or factor Xa inhibition has significantly revolutionized this aspect of treatment for atrial fibrillation patients. This review focuses on the tolerability and efficacy of apixaban and tackles the generalizability of the findings with apixaban to broader patient populations than those primarily enrolled in the clinical trials, drawing from the AVERROES and ARISTOTLE trials and their subsequent secondary analyses. Taken together, findings from these trials show that apixaban is superior to warfarin in preventing stroke with a lower risk of major bleeding in the general population of patients with atrial fibrillation as well as in several key high-risk patient subgroups.
Sherwood, Matthew W.; Becker, Richard C.
Atrial fibrillation is a common arrhythmia. One of the important aspects of the management of atrial fibrillation is stroke prevention. Warfarin has been the longstanding anticoagulant used for stroke prevention in patients with atrial fibrillation. There are now three novel oral anticoagulants, which have been studied in randomized controlled trials and subsequently approved by the Federal Drug Administration for stroke prevention in patients with atrial fibrillation. Special patient populations, including renal insufficiency, elderly, prior stroke, and extreme body weights, were represented to varying degrees in the clinical trials of the novel oral anticoagulants. Furthermore, there is variation in the pharmacokinetics and pharmacodynamics of each anticoagulant, which affect the patient populations differently. Patients and clinicians are faced with the task of selecting among the available anticoagulants, and this review is designed to be a tool for clinical decision-making. PMID:23846737
Dorian, Paul; Angaran, Paul
β-Blockers are among the most frequently used drugs in patients with atrial fibrillation. They are often used for ventricular rate control, acutely in emergency situations and chronically, in patients with persistent or permanent atrial fibrillation. They are also used, with less evidence of benefit, to prevent the first occurrence or recurrence of atrial fibrillation, particularly in patients with hypertension. They are effective in reducing ventricular rate, potentially leading to an improvement in symptoms and well-being. They are particularly indicated in patients with heart failure and atrial fibrillation; the choice of β-blockers in this condition should be guided by tolerability and effects on symptoms and well-being. Copyright © 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.
Spivak, Inna E
Anticoagulation is an important strategy for the prevention of stroke associated with atrial fibrillation. Development of new oral agents has created a need to educate nurses to administer these medications and provide patient education.
Patel, Taral K.; Passman, Rod S.
Opinion statement 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. PMID:23397289
The Maze procedure was the first surgical technique developed to ablate, rather than isolate, atrial fibrillation and was first performed clinically in 1987. The experimental and clinical electrophysiological maps on which the Maze procedure was based demonstrated the presence of two or more large (5-6 cm diameter) macro-reentrant circuits during established atrial fibrillation (AF). Eleven years later, focal triggers were identified, primarily in and around the pulmonary veins, and were shown to be responsible for the induction of individual episodes of AF. Thus, it became clear that episodes of paroxysmal AF could be treated in most patients by isolating or ablating the region of the pulmonary veins, but that once AF became non-paroxysmal and thus dependent upon the macro-reentrant circuits for its maintenance, it would still be necessary to perform some type of additional procedure to interrupt those circuits. Approximately 100,000 patients who undergo coronary artery bypass grafting (CABG), aortic valve replacement (AVR) or mitral valve surgery in the US also have associated AF, but only 20% of them undergo a concomitant procedure to ablate the AF. However, multiple studies have demonstrated that treating the AF at the time of these other primary operations results in an improved quality of life, fewer long-term strokes and improved long-term survival while adding no risk to the overall surgical procedure. Moreover, the major cardiology and surgery societies recommend that concomitant AF surgery be performed in all cases when feasible. Patients undergoing CABG and AVR who have paroxysmal AF should undergo pulmonary vein isolation, while those with non-paroxysmal AF (persistent or long-standing persistent AF) should have a Maze procedure. Patients undergoing mitral valve surgery who have either paroxysmal AF or non-paroxysmal AF should undergo a Maze procedure. PMID:24516803
Calvo, David; Atienza, Felipe; Jalife, José; Martínez-Alzamora, Nieves; Bravo, Loreto; Almendral, Jesús; González-Torrecilla, Esteban; Arenal, Ángel; Bermejo, Javier; Fernández-Avilés, Francisco; Berenfeld, Omer
Aims Research on paroxysmal atrial fibrillation (AF) assumes that fibrillation induced by rapid pacing adequately reproduces spontaneously occurring paroxysmal AF in humans. We aimed to compare the spectral properties of spontaneous vs. induced AF episodes in paroxysmal AF patients. Methods and results Eighty-five paroxysmal AF patients arriving in sinus rhythm to the electrophysiology laboratory were evaluated prior to ablation. Atrial fibrillation was induced by rapid pacing from the pulmonary vein-left atrial junctions (PV-LAJ), the coronary sinus (CS), or the high right atrium (HRA). Simultaneous recordings were obtained using multipolar catheters. Off-line power spectral analysis of 5 s bipolar electrograms was used to determine dominant frequency (DF) at recording sites with regularity index >0.2. Sixty-eight episodes were analysed for DF. Comparisons were made between spontaneous (n= 23) and induced (n= 45) AF episodes at each recording site. No significant differences were observed between spontaneous and induced AF episodes in HRA (5.18 ± 0.69 vs. 5.06 ± 0.91 Hz; P= 0.64), CS (5.27 ± 0.69 vs. 5.36 ± 0.76 Hz; P= 0.69), or LA (5.72 ± 0.88 vs. 5.64 ± 0.75 Hz; P= 0.7) regardless of pacing site. Consistent with these results, paired analysis in seven patients with both spontaneous and induced AF episodes, showed no regional DFs differences. Moreover, a left-to-right DF gradient was also present in both spontaneous (PV-LAJ 5.71 ± 0.81 vs. HRA 5.18 ± 0.69 Hz; P= 0.005) and induced (PV-LAJ 5.62 ± 0.72 vs. HRA 5.07 ± 0.91 Hz; P= 0.002) AF episodes, with no differences between them (P= not specific). Conclusion In patients with paroxysmal AF, high-rate pacing-induced AF adequately mimics spontaneously initiated AF, regardless of induction site. PMID:22696516
Pallisgaard, Jannik L; Schjerning, Anne-Marie; Lindhardt, Tommi B; Procida, Kristina; Hansen, Morten L; Torp-Pedersen, Christian; Gislason, Gunnar H
Diabetes has been associated with atrial fibrillation but the current evidence is conflicting. In particular knowledge regarding young diabetes patients and the risk of developing atrial fibrillation is sparse. The aim of our study was to investigate the risk of atrial fibrillation in patients with diabetes compared to the background population in Denmark. Through Danish nationwide registries we included persons above 18 years of age and without prior atrial fibrillation and/or diabetes from 1996 to 2012. The study cohort was divided into a background population without diabetes and a diabetes group. The absolute risk of developing atrial fibrillation was calculated and Poisson regression models adjusted for sex, age and comorbidities were used to calculate incidence rate ratios of atrial fibrillation. The total study cohort included 5,081,087 persons, 4,827,713 (95%) in the background population and 253,374 (5%) in the diabetes group. Incidence rates of atrial fibrillation per 1000 person years were stratified in four age groups from 18 to 39, 40 to 64, 65 to 74 and 75 to 100 years giving incidence rates (95% confidence intervals) of 0.02 (0.02-0.02), 0.99 (0.98-1.01), 8.89 (8.81-8.98) and 20.0 (19.9-20.2) in the background population and 0.13 (0.09-0.20), 2.10 (2.00-2.20), 8.41 (8.10-8.74) and 20.1 (19.4-20.8) in the diabetes group, respectively. The adjusted incidence rate ratios in the diabetes group with the background population as reference were 2.34 (1.52-3.60), 1.52 (1.47-1.56), 1.20 (1.18-1.23) and 0.99 (0.97-1.01) in the four age groups, respectively. Diabetes is an independent risk factor for developing atrial fibrillation/flutter, most pronounced in young diabetes patients. Routine screening for atrial fibrillation/flutter in diabetes patients might be beneficial and have therapeutic implications, especially in younger diabetes patients. Diabetes increases the risk of developing atrial fibrillation and especially young diabetes patients have a high
Shi, J H; Xing, A J; Wang, Y Z; Ji, C P; Zhu, C R; Wei, X M; Wu, S L
To observe the association between the cardiovascular health score and new-onset atrial fibrillation. A total of 95 026 participants who participated the health examination between July 2006 and October 2007 at Kailuan group and without history of atrial fibrillation were selected as the observation cohort. The second, the third and the fourth health examination were performed between July 2008 to October 2009, July 2010 to October 2011, July 2012 to October 2013, respectively.A total of 85 028 participants were included in the final analysis after excluding participants who had new-onset valvular atrial fibrillation and participants lost to follow-up. The participants were divided into 4 subgroups by cardiovascular health score at baseline according to the definition of AHA and cardiovascular health scoring system, namely group of 0-6 points (n=11 103), 7-8 points (n=24 487), 9-10 points (n=32 556), and 11-14 points (n=16 882). The incidence of atrial fibrillation in each subgroup was observed, and the association between cardiovascular health score and risk of new-onset atrial fibrillation was analyzed using multiple Cox regression analysis. A total of 254 participants developed atrial fibrillation during the median of (5.6±1.4) years follow-up. The total incidence of new-onset atrial fibrillation was 0.53/1 000 person-year. The incidence of atrial fibrillation was 0.69/1 000 person-year, 0.60/1 000 person-year, 0.56/1 000 person-year, and 0.30/1 000 person-year, respectively in 0-6 points, 7-8 points, 9-10 points, and 11-14 points subgroups, respectively(P<0.01). After adjustment of age, gender, education level, income, drink, history of myocardial infarction, history of stroke, serum uric acid and C reactive protein level, multiple Cox regression analysis showed that one health score point increase was related to 8% reduction of new onset atrial fibrillation(HR=0.92, 95%CI 0.86-0.99, P<0.05). Compared with the group of 0-6 points group, the risk of atrial
Lalani, Gautam G.; Schricker, Amir; Gibson, Michael; Rostamian, Armand; Krummen, David E.; Narayan, Sanjiv M.
Objectives The aim of this study was to determine whether onset sites of human atrial fibrillation (AF) exhibit conduction slowing, reduced amplitude, and/or prolonged duration of signals (i.e., fractionation) immediately before AF onset. Background Few studies have identified functional determinants of AF initiation. Because conduction slowing is required for reentry, we hypothesized that AF from pulmonary vein triggers might initiate at sites exhibiting rate-dependent slowing in conduction velocity (CV restitution) or local slowing evidenced by signal fractionation. Methods In 28 patients with AF (left atrial size 43 ± 5 mm; n = 13 persistent) and 3 control subjects (no AF) at electrophysiological study, we measured bi-atrial conduction time (CT) electrogram fractionation at 64 or 128 electrodes with baskets in left (n = 17) or both (n = 14) atria during superior pulmonary vein pacing at cycle lengths (CL) accelerating from 500 ms (120 beats/min) to AF onset. Results Atrial fibrillation initiated in 19 of 28 AF patients and no control subjects. During rate acceleration, conduction slowed in 23 of 28 AF patients (vs. no control subjects, p = 0.01) at the site of AF initiation (15 of 19) or latest activated site (20 of 28). The CT lengthened from 79 ± 23 ms to 107 ± 39 ms (p < 0.001) on acceleration, in a spectrum from persistent AF (greatest slowing) to control subjects (least slowing; p < 0.05). Three patterns of CV restitution were observed: 1) broad (gradual CT prolongation, 37% patients); 2) steep (abrupt prolongation, at CL 266 ± 62 ms, 42%); and 3) flat (no prolongation, 21% AF patients, all control subjects). The AF initiation was more prevalent in patients with CV restitution (17 of 23 vs. 2 of 8; p = 0.03) and immediately followed abrupt reorientation of the activation vector in patients with broad but not steep CV restitution (p < 0.01). Patients with broad CV restitution had larger atria (p = 0.03) and were more likely to have persistent AF (p = 0
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
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
Cappellari, Manuel; Carletti, Monica; Danese, Alessandra; Bovi, Paolo
Direct oral anticoagulants (DOACs) are superior to warfarin in reduction of the intracranial bleeding risk. The aim of the present study was to assess whether early DOAC introduction (1-3 days after onset) in stroke patients with non-valvular atrial fibrillation (nVAF) may be safe and effective, compared with DOAC introduction after 4-7 days. We conducted a prospective analysis based on data collected from 147 consecutive nVAF patients who started DOAC within 7 days after stroke onset. In all patients, we performed pre-DOAC CT scan 24-36 h after onset and follow-up CT scan at 7 days after DOAC introduction. Outcome measures were post-DOAC intracranial bleeding (new any intracerebral hemorrhage (ICH) in patients with pre-DOAC infarct without hemorrhagic transformation (HT) or expansion of ICH in patients with pre-DOAC infarct with asymptomatic HT) and post-DOAC recurrent ischemic stroke (any new ischemic infarct) on follow-up CT scan. 97 patients started DOAC after 1-3 days and 50 patients started DOAC after 4-7 days. On pre-DOAC CT scan, 132 patients had an infarct without HT and 15 an infarct with asymptomatic HT. On follow-up CT scan, new any ICH was noted in seven patients (asymptomatic in 6) and asymptomatic expansion of ICH in one patient. We found no association between early DOAC introduction and intracranial bleeding. Large infarct remained the only independent predictor of post-DOAC intracranial bleeding. No patients suffered recurrent ischemic stroke after DOAC introduction. Early DOAC introduction might be safe in carefully selected patients with nVAF who experience small- and medium-sized cardioembolic ischemic strokes. Further investigation will be needed.
Dillon, Patrick; Ghanbari, Hamid
In this article, a review of the diagnostic evaluation and outpatient follow-up of patients with atrial fibrillation is presented. After exploring details of symptoms, past medical history, quality of life, and physical exam findings, diagnostic tools are then discussed. Furthermore, important considerations after the initial diagnosis and treatment of patients with atrial fibrillation are discussed. Copyright © 2014 Elsevier Inc. All rights reserved.
Tu, Hans T; Chen, Ziyuan; Swift, Corey; Churilov, Leonid; Guo, Ruibing; Liu, Xinfeng; Jannes, Jim; Mok, Vincent; Freedman, Ben; Davis, Stephen M; Yan, Bernard
Rationale Paroxysmal atrial fibrillation is a common and preventable cause of devastating strokes. However, currently available monitoring methods, including Holter monitoring, cardiac telemetry and event loop recorders, have drawbacks that restrict their application in the general stroke population. AliveCor™ heart monitor, a novel device that embeds miniaturized electrocardiography (ECG) in a smartphone case coupled with an application to record and diagnose the ECG, has recently been shown to provide an accurate and sensitive single lead ECG diagnosis of atrial fibrillation. This device could be used by nurses to record a 30-s ECG instead of manual pulse taking and automatically provide a diagnosis of atrial fibrillation. Aims To compare the proportion of patients with paroxysmal atrial fibrillation detected by AliveCor™ ECG monitoring with current standard practice. Sample size 296 Patients. Design Consecutive ischemic stroke and transient ischemic attack patients presenting to participating stroke units without known atrial fibrillation will undergo intermittent AliveCor™ ECG monitoring administered by nursing staff at the same frequency as the vital observations of pulse and blood pressure until discharge, in addition to the standard testing paradigm of each participating stroke unit to detect paroxysmal atrial fibrillation. Study outcome Proportion of patients with paroxysmal atrial fibrillation detected by AliveCor™ ECG monitoring compared to 12-lead ECG, 24-h Holter monitoring and cardiac telemetry. Discussion Use of AliveCor™ heart monitor as part of routine stroke unit nursing observation has the potential to be an inexpensive non-invasive method to increase paroxysmal atrial fibrillation detection, leading to improvement in stroke secondary prevention.
AGENCY USE ONLY (Leaveblank/ 2. REPORT DATE 3. REPORT TYPE AND DATES COVERED 19Junl998 4. TITLE AND SUBTITLE QUALITY OF LIFE AND PHYSICAL CAPACITY...Quality of Life and Physical Capacity of Older Ambulatory Adults with Rate-Controlled Atrial Fibrillation A Thesis Submitted to the Yale University...QUAHTY mSPECJTBD I ABSTRACT Quality of Life and Physical Capacity of Older Ambulatory Adults with Rate-Controlled Atrial Fibrillation Michael
Gumbinger, C; Krumsdorf, U; Veltkamp, R; Hacke, W; Ringleb, P
Detection of atrial fibrillation is of vital importance because oral anticoagulation decreases the risk of a stroke by 64%. Current standards for stroke unit treatment require continuous electrocardiogram (ECG) monitoring for at least 24 h. Additionally, a 24-h HOLTER ECG (HOLTER) should be performed in selected patients. It remains unclear whether continuous monitoring at the bedside is equivalent to HOLTER for the detection of atrial fibrillation. Furthermore, we investigate how many additional patients with paroxysmal atrial fibrillation can be identified as a result of a longer duration of continuous monitoring. In this study, we prospectively compared the detection rates of HOLTER and 24-h monitoring at the Stroke Unit at the University of Heidelberg over a period of 9 months. Continuous monitoring was analyzed by trained nurses, HOLTER by cardiologists. We included 370 patients with ischemic stroke or transient ischemic attack (TIA) in our study. Of these, 192 patients underwent HOLTER. Previously unknown atrial fibrillation was detected in 44 patients, 13 patients had no atrial fibrillation in baseline ECG, but atrial fibrillation was detected by continuous monitoring. In two patients, the HOLTER showed atrial fibrillation; both patients had also been detected by continuous monitoring. Median time to detection of the atrial fibrillation during continuous monitoring was 43 h after hospitalization. In this study, use of HOLTER does not give any additional benefit in comparison with continuous monitoring with intermittent analysis by trained staff alone. The median detection time of 43 h emphasizes the importance of longer continuous monitoring. © 2011 The Author(s). European Journal of Neurology © 2011 EFNS.
Dong, Yan; Yao, Kuiwu; Jiang, Wenrui
Atrial fibrillation (AF) is the most common cardiac arrhythmia, which is related to many card