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Sample records for atrial fibrillation animal

  1. Atrial Fibrillation

    MedlinePlus

    ... with the speed or rhythm of the heartbeat. Atrial fibrillation (AF) is the most common type of arrhythmia. The ... the heart's electrical system. Often, people who have AF may not even feel symptoms. But you may ...

  2. Atrial Fibrillation.

    PubMed

    Goralnick, Eric; Bontempo, Laura J

    2015-08-01

    Atrial fibrillation (AF) is a supraventricular tachyarrhythmia that results from the chaotic depolarization of atrial tissue. AF is the most common sustained cardiac dysrhythmia and the most common dysrhythmia diagnosed in US emergency departments. All patients with AF must have their cardioembolic risk assessed, even if sinus rhythm is restored. Novel oral anticoagulants may be considered instead of vitamin K antagonists for anticoagulation in patients with nonvalvular AF. PMID:26226868

  3. [Study and investigation of mechanism of atrial fibrillation--(II). Atrial fibrillation animal model and data analysis method].

    PubMed

    Zhang, Cuiying; Zhang, Shangjun

    2007-10-01

    The first thorny problem in the study of atrial fibrillation (AF) is the establishment of reliable animal models. This paper presents how to create a canine sterile pericarditis model. A new data analysis method, Fast Fourier Transform is introduced. The data from canine sterile pericarditis model was analyzed using FFT. The results demonstrate that canine sterile pericarditis model is a reliable animal model for studying AF and that FFT is a rapid and effective method for analyzing AF data. PMID:18027692

  4. Atrial fibrillation.

    PubMed

    Essential facts Atrial fibrillation (AF) causes an abnormal, sometimes fast pulse, and is the most common heart rhythm disturbance. It occurs when electrical impulses controlling the heart's natural rhythm lose co-ordination. People with AF have a four or five times higher risk of stroke because it increases the risk of a blood clot forming in the chambers of the heart. The condition is responsible for 22,500 strokes a year in the UK, according to the British Heart Foundation (BHF). PMID:24593083

  5. Atrial fibrillation

    PubMed Central

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

    2014-01-01

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

  6. Atrial fibrillation.

    PubMed

    Bang, Casper N

    2013-10-01

    Atrial fibrillation (AF) is a common complication after myocardial infarction (MI) and new-onset AF has been demonstrated to be associated with adverse outcome and a large excess risk of death in both MI and aortic stenosis (AS) patients. Prevention of new-onset AF is therefore a potential therapeutic target in AS and MI patients. Lipid-lowering drugs, particularly statins, have anti-inflammatory and antioxidant properties that may prevent AF. Accordingly, statins are recommended as a class IIa recommendation for prevention of new-onset AF after coronary artery bypass grafting (CABG). However, this preventive effect has not been investigated on new-onset AF in asymptomatic patients with AS or a large scale first-time MI patient sample and data in patients not undergoing invasive cardiac interventions are limited. This PhD thesis was conducted at the Heart Centre, Rigshospitalet, Denmark, with the aim to investigate the three aforementioned questions and to add to the existing evidence of AF prevention with statins. This was done using three different settings: 1) a randomized patients sample of 1,873 from the Simvastatin and Ezetimibe in Aortic Stenosis (SEAS) study, 2) a register patient sample of 97,499 with first-time MI, and 3) all published studies until beginning of June 2011 examining statin treatment on new-onset and recurrent AF in patients not undergoing cardiac surgery. This thesis revealed that statins did not lower the incidence or the time to new-onset AF in patients with asymptomatic AS. However, statin treatment showed an independently preventive effect on new-onset AF, including type-dependent effect and a trend to dosage-dependent effect. In addition, this thesis showed that good compliance to statin treatment was important to prevent new-onset AF. Finally, the meta-analysis in this PhD thesis showed a preventive effect in the observational studies although this effect was absent in the randomized controlled trials. Based on this PhD thesis

  7. Atrial Fibrillation Medications

    MedlinePlus

    ... 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 ...

  8. What Is Atrial Fibrillation?

    MedlinePlus

    ... regular beat. Certain cells in your heart make electric signals that cause the heart to contract and ... read your ECG to find out if the electric signals are normal. In atrial fibrillation (AFib), the ...

  9. Lifestyle and atrial fibrillation.

    PubMed

    Mattioli, Anna Vittoria

    2011-07-01

    Lifestyle factors, in particular dietary intake, have been recognized as important, modifiable risk factors for cardiovascular disease. Consuming a heart-healthy diet lowers the individual's risk for cardiovascular disease. Data on the relationship between lifestyle and atrial fibrillation are controversial; however, the strong association between obesity, atrial/ventricular dysfunction and a nonhealthy lifestyle and atrial fibrillation, suggests that a correction of nutritional habits could prevent the development of arrhythmias through a reduction of underlying cardiac diseases. Today, the Mediterranean diet is considered one of the most effective in terms of its prevention of cardiovascular disease.

  10. Anticoagulation in atrial fibrillation

    PubMed Central

    Piccini, Jonathan P

    2014-01-01

    Atrial fibrillation increases the risk of stroke, which is a leading cause of death and disability worldwide. The use of oral anticoagulation in patients with atrial fibrillation at moderate or high risk of stroke, estimated by established criteria, improves outcomes. However, to ensure that the benefits exceed the risks of bleeding, appropriate patient selection is essential. Vitamin K antagonism has been the mainstay of treatment; however, newer drugs with novel mechanisms are also available. These novel oral anticoagulants (direct thrombin inhibitors and factor Xa inhibitors) obviate many of warfarin’s shortcomings, and they have demonstrated safety and efficacy in large randomized trials of patients with non-valvular atrial fibrillation. However, the management of patients taking warfarin or novel agents remains a clinical challenge. There are several important considerations when selecting anticoagulant therapy for patients with atrial fibrillation. This review will discuss the rationale for anticoagulation in patients with atrial fibrillation; risk stratification for treatment; available agents; the appropriate implementation of these agents; and additional, specific clinical considerations for treatment. PMID:24733535

  11. Emergency management of atrial fibrillation

    PubMed Central

    Wakai, A; O'Neill, J

    2003-01-01

    Atrial fibrillation is the most common cardiac arrhythmia managed by emergency and acute general physicians. There is increasing evidence that selected patients with acute atrial fibrillation can be safely managed in the emergency department without the need for hospital admission. Meanwhile, there is significant variation in the current emergency management of acute atrial fibrillation. This review discusses evidence based emergency management of atrial fibrillation. The principles of emergency management of acute atrial fibrillation and the subset of patients who may not need hospital admission are reviewed. Finally, the need for evidence based guidelines before emergency department based clinical pathways for the management of acute atrial fibrillation becomes routine clinical practice is highlighted. PMID:12840118

  12. Hyperuricemia and Atrial Fibrillation.

    PubMed

    Maharani, Nani; Kuwabara, Masanari; Hisatome, Ichiro

    2016-07-27

    The importance of atrial fibrillation (AF) as a cause of mortality and morbidity has prompted research on its pathogenesis and treatment. Recognition of AF risk factors is essential to prevent it and reduce the risk of death. Hyperuricemia has been widely accepted to be associated with the incidence of paroxysmal or persistent AF, as well as to the risk of AF in post cardiovascular surgery patients. The possible explanations for this association have been based on their relation with either oxidative stress or inflammation. To investigate the link between hyperuricemia and AF, it is necessary to refer to hyperuricemia-induced atrial remodeling. So far, both ionic channel and structural remodeling caused by hyperuricemia might be plausible explanations for the occurrence of AF. Inhibition of xanthine oxidase and nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase, or the use of antioxidants, along with serum uric acid (SUA) level reduction to prevent inflammation, might be useful. Uric acid transporters (UATs) play a key role in the regulation of intracellular uric acid concentration. Intracellular rather than serum uric acid level is considered more important for the pathogenesis of AF. Identification of UATs expressed in cells is thus important, and targeting UATs might become a potential strategy to reduce the risk of hyperuricemia-induced atrial fibrillation. PMID:27396561

  13. Obesity and atrial fibrillation.

    PubMed

    Abed, H S; Wittert, G A

    2013-11-01

    Atrial fibrillation (AF) is an increasing public health problem, often described as the epidemic of the new millennium. The rising health economic impact of AF, its association with poor quality of life and independent probability of increased mortality, has recently been highlighted. Although population ageing is regarded as an important contributor to this epidemic, obesity and its associated cardiometabolic comorbidities may represent the principal driving factor behind the current and projected AF epidemic. Obesity-related risk factors, such as hypertension, vascular disease, obstructive sleep apnea and pericardial fat, are thought to result in atrial electro-structural dysfunction. In addition, insulin resistance, its associated abnormalities in nutrient utilization and intermediary metabolic by-products are associated with structural and functional abnormalities, ultimately promoting AF. Recent elucidation of molecular pathways, including those responsible for atrial fibrosis, have provided mechanistic insights and the potential for targeted pharmacotherapy. In this article, we review the evidence for an obesity-related atrial electromechanical dysfunction, the mechanisms behind this and its impact on AF therapeutic outcomes. In light of the recently described mechanisms, we illustrate proposed management approaches and avenues for further investigations.

  14. Genetics Home Reference: familial atrial fibrillation

    MedlinePlus

    ... fibrillation also increases the risk of stroke and sudden death. Complications of familial atrial fibrillation can occur at ... beats , increasing the risk of syncope, stroke, and sudden death. Most cases of atrial fibrillation are not caused ...

  15. [Perioperative management of atrial fibrillation].

    PubMed

    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

    2014-05-01

    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.

  16. Rhythm control in atrial fibrillation.

    PubMed

    Piccini, Jonathan P; Fauchier, Laurent

    2016-08-20

    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. PMID:27560278

  17. Rate control in atrial fibrillation.

    PubMed

    Van Gelder, Isabelle C; Rienstra, Michiel; Crijns, Harry J G M; Olshansky, Brian

    2016-08-20

    Control of the heart rate (rate control) is central to atrial fibrillation management, even for patients who ultimately require control of the rhythm. We review heart rate control in patients with atrial fibrillation, including the rationale for the intervention, patient selection, and the treatments available. The choice of rate control depends on the symptoms and clinical characteristics of the patient, but for all patients with atrial fibrillation, rate control is part of the management. Choice of drugs is patient-dependent. β blockers, alone or in combination with digoxin, or non-dihydropyridine calcium-channel blockers (not in heart failure) effectively lower the heart rate. Digoxin is least effective, but a reasonable choice for physically inactive patients aged 80 years or older, in whom other treatments are ineffective or are contraindicated, and as an additional drug to other rate-controlling drugs, especially in heart failure when instituted cautiously. Atrioventricular node ablation with pacemaker insertion for rate control should be used as an approach of last resort but is also an option early in the management of patients with atrial fibrillation treated with cardiac resynchronisation therapy. However, catheter ablation of atrial fibrillation should be considered before atrioventricular node ablation. Although rate control is a top priority and one of the first management issues for all patients with atrial fibrillation, many issues remain. PMID:27560277

  18. Rhythm control in atrial fibrillation.

    PubMed

    Piccini, Jonathan P; Fauchier, Laurent

    2016-08-20

    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.

  19. Stroke prevention in atrial fibrillation.

    PubMed

    Freedman, Ben; Potpara, Tatjana S; Lip, Gregory Y H

    2016-08-20

    Atrial fibrillation is found in a third of all ischaemic strokes, even more after post-stroke atrial fibrillation monitoring. Data from stroke registries show that both unknown and untreated or under treated atrial fibrillation is responsible for most of these strokes, which are often fatal or debilitating. Most could be prevented if efforts were directed towards detection of atrial fibrillation before stroke occurs, through screening or case finding, and treatment of all patients with atrial fibrillation at increased risk of stroke with well-controlled vitamin K antagonists or non-vitamin K antagonist anticoagulants. The default strategy should be to offer anticoagulant thromboprophylaxis to all patients with atrial fibrillation unless defined as truly low risk by simple validated risk scores, such as CHA2DS2-VASc. Assessment of bleeding risk using the HAS-BLED score should focus attention on reversible bleeding risk factors. Finally, patients need support from physicians and various other sources to start anticoagulant treatment and to ensure adherence to and persistence with treatment in the long term. PMID:27560276

  20. Organized Atrial Tachycardias after Atrial Fibrillation Ablation

    PubMed Central

    Castrejón-Castrejón, Sergio; Ortega, Marta; Pérez-Silva, Armando; Doiny, David; Estrada, Alejandro; Filgueiras, David; López-Sendón, José L.; Merino, José L.

    2011-01-01

    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

  1. [Panic disorder and atrial fibrillation].

    PubMed

    Olazabal Eizaguirre, N; Chavez, R; González-Torres, M A; Gaviria, M

    2013-10-01

    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.

  2. [Atrial fibrillation and physical activity].

    PubMed

    Apor, Péter

    2013-03-31

    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. PMID:23524234

  3. Atrial natriuretic peptide frameshift mutation in familial atrial fibrillation.

    PubMed

    Hodgson-Zingman, Denice M; Karst, Margaret L; Zingman, Leonid V; Heublein, Denise M; Darbar, Dawood; Herron, Kathleen J; Ballew, Jeffrey D; de Andrade, Mariza; Burnett, John C; Olson, Timothy M

    2008-07-10

    Atrial fibrillation is a common arrhythmia that is hereditary in a small subgroup of patients. In a family with 11 clinically affected members, we mapped an atrial fibrillation locus to chromosome 1p36-p35 and identified a heterozygous frameshift mutation in the gene encoding atrial natriuretic peptide. Circulating chimeric atrial natriuretic peptide (ANP) was detected in high concentration in subjects with the mutation, and shortened atrial action potentials were seen in an isolated heart model, creating a possible substrate for atrial fibrillation. This report implicates perturbation of the atrial natriuretic peptide-cyclic guanosine monophosphate (cGMP) pathway in cardiac electrical instability. PMID:18614783

  4. Atrial fibrillation or flutter

    MedlinePlus

    ... the mitral valve) Hypertension Medicines Overactive thyroid gland ( hyperthyroidism ) Pericarditis Sick sinus syndrome Symptoms You may not ... procedures Heart attack Heart pacemaker High blood pressure Hyperthyroidism Pericarditis Pulse Stable angina Stroke Patient Instructions Atrial ...

  5. Atrial Fibrillation - Multiple Languages: MedlinePlus

    MedlinePlus

    ... Atrial Fibrillation (Arabic) العربية Bilingual PDF Health Information Translations Chinese - Simplified (简体中文) Atrial Fibrillation 心房纤维颤动 - 简体中文 (Chinese - Simplified) Bilingual PDF Health Information Translations Chinese - Traditional (繁體中文) Atrial Fibrillation 心房纖維顫動 - 繁體中文 (Chinese - ...

  6. Almanac 2015: atrial fibrillation research in Heart

    PubMed Central

    Jawad-Ul-Qamar, Muhammad; Kirchhof, Paulus

    2016-01-01

    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

  7. Aspirin Often Wrongly Prescribed for Atrial Fibrillation

    MedlinePlus

    ... page: https://medlineplus.gov/news/fullstory_159459.html Aspirin Often Wrongly Prescribed for Atrial Fibrillation Blood thinners -- not aspirin -- dramatically cut the risk of stroke, researchers say ...

  8. Atrial fibrillation and physical activity

    PubMed Central

    Bosomworth, N. John

    2015-01-01

    Objective 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. Data sources 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. Study selection 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. Synthesis 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. Conclusion 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. PMID:26668285

  9. Atrial Fibrillation Ablation and Stroke.

    PubMed

    Aagaard, Philip; Briceno, David; Csanadi, Zoltan; Mohanty, Sanghamitra; Gianni, Carola; Trivedi, Chintan; Nagy-Baló, Edina; Danik, Stephan; Barrett, Conor; Santoro, Francesco; Burkhardt, J David; Sanchez, Javier; Natale, Andrea; Di Biase, Luigi

    2016-05-01

    Catheter ablation has become a widely available and accepted treatment to restore sinus rhythm in atrial fibrillation patients who fail antiarrhythmic drug therapy. Although generally safe, the procedure carries a non-negligible risk of complications, including periprocedural cerebral insults. Uninterrupted anticoagulation, maintenance of an adequate ACT during the procedure, and measures to avoid and detect thrombus build-up on sheaths and atheters during the procedure, appears useful to reduce the risk of embolic events. This is a review of the incidence, mechanisms, impact, and methods to reduce catheter ablation related cerebral insults. PMID:27150179

  10. Familial atrial fibrillation with fetal onset

    PubMed Central

    Tikanoja, T; Kirkinen, P; Nikolajev, K; Eresmaa, L; Haring, P

    1998-01-01

    A woman presented during two pregnancies (at 25 and 23 weeks' gestation, respectively) because the fetuses had rapid, irregular tachycardia and hydrops. After maternal drug treatment and achievement of slower fetal heart rates, the hydrops gradually resolved. Both babies were born full term with continuing atrial fibrillation. In the first, an ectopic atrial rhythm was temporarily achieved during high dose flecainide treatment but, in the younger sibling, all medications and repeated cardioversions failed even temporarily to convert the atrial fibrillation with an almost isoelectric baseline in ECG to sinus rhythm. Good rate control has been achieved with digoxin in both patients. No infective, immunological, or structural cause was found in either case, and thus an inherited aetiology is probable.

 Keywords: atrial fibrillation;  arrhythmias;  fetal atrial fibrillation;  familial arrhythmias PMID:9538316

  11. Minimally Invasive Surgical Therapies for Atrial Fibrillation

    PubMed Central

    Nakamura, Yoshitsugu; Kiaii, Bob; Chu, Michael W. A.

    2012-01-01

    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

  12. Atrial Fibrillation During an Exploration Class Mission

    NASA Technical Reports Server (NTRS)

    Lipsett, Mark; Hamilton, Douglas; Lemery, Jay; Polk, James

    2011-01-01

    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.

  13. [Cardiac rehabilitation in patients with atrial fibrillation].

    PubMed

    Schlitt, Axel; Kamke, Wolfram; Guha, Manju; Haberecht, Olaf; Völler, Heinz

    2015-06-01

    The course of cardiac rehabilitation is often altered due to episodes of paroxysmal, predominantly postoperative atrial fibrillation. In symptomatic patients, a TEE-guided cardioversion - preferential DC shock - is indicated. In patients with persistent / permanent atrial fibrillation, a heart rate up to 110 / min and 170 / min at rest and during physical activity should, respectively, be tolerated. Therefore, training should not be quitted by heart rate but rather by load. The antithrombotic management is in addition a great task in treating patients with atrial fibrillation. With the exception of patients with a CHA2DS2-VASc-Score < 1, oral anticoagulation is indicated. Atrial fibrillation has little impact on social aspects, whereas the underlying heart disease and drug treatment (oral anticoagulation) has an important impact.

  14. Atrial fibrillation precipitated by tyramine containing foods.

    PubMed Central

    Jacob, L H; Carron, D B

    1987-01-01

    Episodes of atrial fibrillation that occurred after meals developed in a 60 year old man with a history of ischaemic heart disease. The attacks were precipitated by precursors and metabolites of tyramine and tyramine containing foods and drinks, in the absence of monoamine oxidase inhibitors. The patient has remained free of atrial fibrillation for the past twelve months on a diet that does not contain tyramine. PMID:3814458

  15. Antithrombotic treatment of atrial fibrillation: new insights.

    PubMed

    Le Heuzey, J Y

    2012-10-01

    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. PMID:23026665

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  17. Ageing related down-regulation of myocardial connexin-43 and up-regulation of MMP-2 may predict propensity to atrial fibrillation in experimental animals.

    PubMed

    Nagibin, V; Egan Benova, T; Viczenczova, C; Szeiffova Bacova, B; Dovinova, I; Barancik, M; Tribulova, N

    2016-09-19

    Mechanisms underlying atrial fibrillation (AF), the most common cardiac arrhythmia, particularly in aged population, are not fully elucidated. We have previously shown an increased propensity of old guinea pigs (GPs) heart to inducible AF when comparing to young animals. This study aimed to verify our hypothesis that susceptibility of aged heart to AF may be attributed to abnormalities in myocardial connexin-43 (Cx43) and extracellular matrix that affect cardiac electrical properties. Experiments were conducted on male and female 4-week-old and 24-week-old GPs. Atrial tissue was processed for analysis of Cx43 topology using immunohistochemistry, expression of Cx43 protein using immunobloting, and expression of mRNA of Cx43 and extracellular matrix metalloproteinase-2 (MMP-2) using real time PCR. Immunohistochemistry revealed uniform Cx43 distribution predominantly on lateral sides of the cardiomyocytes of young male and female GP atria. In contrast, non-uniform distribution, mislocalization and reduced immunolabeling of Cx43 were detected in atria of old GPs. In parallel, the atrial tissue levels of Cx43 mRNA were significantly decreased, while mRNA expression of MMP-2 was significantly increased in old versus young GPs. The changes were more pronounced in old GPs males comparing to females. Findings indicate that age-related down-regulation of atrial Cx43 and up-regulation of MMP-2 as well as disordered Cx43 distribution can facilitate development of AF in old guinea pig hearts. PMID:27643943

  18. What Are the Signs and Symptoms of Atrial Fibrillation?

    MedlinePlus

    ... from the NHLBI on Twitter. What Are the Signs and Symptoms of Atrial Fibrillation? Atrial fibrillation (AF) ... the lungs and body. This can lead to signs and symptoms, such as: Palpitations (feelings that your ...

  19. Practice implications of the Atrial Fibrillation Guidelines.

    PubMed

    Curtis, Anne B

    2013-06-01

    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.

  20. [New antiarrhythmic drugs for atrial fibrillation].

    PubMed

    Drici, M-D

    2009-12-01

    The development of new antiarrhythmic drugs is mainly aimed to treat atrial fibrillation, because of its prevalence and major consequences in terms cerebral vascular thrombosis. Specific blockade of I(Na) et I(K), even if efficacious, have previously shown to be proarrhythmogenic, with a global impairment of the cardiac patient's outcome. This lead to the development of new drugs, selectively targeting atrial currents such as I(Kur) ou I(KAch). The efficacy of amiodarone in treatment of atrial fibrillation has also yielded a whole array of new antiarrhythmic drugs targeting both these atrial currents but also sharing amiodarone pharmacodynamics properties. This renders the Vaughan-Williams classification ill-adapted for such drugs.

  1. Antithrombotic Therapy for Atrial Fibrillation

    PubMed Central

    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.

    2012-01-01

    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

  2. Diagnosis and Treatment of Atrial Fibrillation.

    PubMed

    Gutierrez, Cecilia; Blanchard, Daniel G

    2016-09-15

    Atrial fibrillation is a supraventricular arrhythmia that adversely affects cardiac function and increases the risk of stroke. It is the most common arrhythmia and a major source of morbidity and mortality; its prevalence increases with age. Pulse rate is sensitive, but not specific, for diagnosis, and suspected atrial fibrillation should be confirmed with 12-lead electrocardiography. Because normal electrocardiographic findings do not rule out atrial fibrillation, home monitoring is recommended if there is clinical suspicion of arrhythmia despite normal test results. Treatment is based on decisions made regarding when to convert to normal sinus rhythm vs. when to treat with rate control, and, in either case, how to best reduce the risk of stroke. For most patients, rate control is preferred to rhythm control. Ablation therapy is used to destroy abnormal foci responsible for atrial fibrillation. Anticoagulation reduces the risk of stroke while increasing the risk of bleeding. The CHA2DS2-VASc scoring system assesses the risk of stroke, with a score of 2 or greater indicating a need for anticoagulation. The HAS-BLED score estimates the risk of bleeding. Scores of 3 or greater indicate high risk. Warfarin, dabigatran, factor Xa inhibitors (e.g., rivaroxaban, apixaban, edoxaban), and aspirin are options for stroke prevention. Selection of therapy should be individualized based on risks and potential benefits, cost, and patient preference. Left atrial appendage obliteration is an option for reducing stroke risk. Two implantable devices used to occlude the appendage, the Watchman and the Amplatzer Cardiac Plug, appear to be as effective as warfarin in preventing stroke, but they are invasive. Another percutaneous approach to occlusion, wherein the left atrium is closed off using the Lariat, is also available, but data on its long-term effectiveness and safety are still limited. Surgical treatments for atrial fibrillation are reserved for patients who are undergoing

  3. Spontaneous atrial fibrillation in a freestyle skier.

    PubMed

    Whyte, G; Stephens, N; Sharma, S; Shave, R; Budgett, R; McKenna, W J

    2004-04-01

    A male freestyle skier was found to have atrial fibrillation during a routine physiological assessment. This was found to be associated with the consumption of an unusually large amount of alcohol. Athletes should be counselled about the potential dangers of alcohol consumption before exhaustive exercise.

  4. Atrial Fibrillation: The Science behind Its Defiance

    PubMed Central

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

    2016-01-01

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

  5. Atrial Fibrillation: The Science behind Its Defiance

    PubMed Central

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

    2016-01-01

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

  6. [Progress of anticoagulation therapy in atrial fibrillation].

    PubMed

    Hernández Olmedo, Miguel; Suárez Fernández, Carmen

    2015-08-01

    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.

  7. Atrial fibrillation due to licorice root syrup.

    PubMed

    Erkuş, Musluhittin Emre; Altıparmak, İbrahim Halil; Demirbağ, Recep; Günebakmaz, Özgür

    2016-04-01

    While it is known that consumption of licorice may lead to cardiac arrhythmias, there have been no reports of atrial fibrillation resulting from the consumption of licorice root syrup. A 57-year-old male with no prior history of cardiovascular disease was admitted to the emergency department with palpitation. His electrocardiogram showed atrial fibrillation with a moderate to rapid ventricular rate. In laboratory assessment, potassium was 2.0 mmol/L and plasma renin activity and aldosterone level were suppressed (<300 ng/L/hour, 42 ng/L respectively). Volumes of the heart chambers were within normal range and functions and structures of the heart valves were normal in echocardiographic assessment. The arrhythmia was resolved with propafenone infusion. PMID:27138313

  8. Ogilvie's Syndrome following Cardioversion for Atrial Fibrillation

    PubMed Central

    Al-Halawani, Moh'd; Thawabi, Mohammad; Abdeen, Yazan; Miller, Richard A.; Fedida, Andre A.

    2014-01-01

    Acute colonic pseudoobstruction, also known as Ogilvie's syndrome, is characterized by distension of the colon in the absence of a mechanical obstruction as evident by abdominal radiography. This syndrome is usually treated conservatively; however, medical or surgical therapies can be employed in refractory cases. Ogilvie's syndrome has been reported following cardiac events, such as myocardial infarction, heart failure, and cardiac bypass surgeries. We report the first case of Ogilvie's syndrome following synchronized electric cardioversion for atrial fibrillation. PMID:25214851

  9. Atrial fibrillation and microRNAs

    PubMed Central

    Santulli, Gaetano; Iaccarino, Guido; De Luca, Nicola; Trimarco, Bruno; Condorelli, Gianluigi

    2014-01-01

    Atrial fibrillation (AF) is the most common sustained arrhythmia, especially in the elderly, and has a significant genetic component. Recently, several independent investigators have demonstrated a functional role for small non-coding RNAs (microRNAs) in the pathophysiology of this cardiac arrhythmia. This report represents a systematic and updated appraisal of the main studies that established a mechanistic association between specific microRNAs and AF, focusing both on the regulation of electrical and structural remodeling of cardiac tissue. PMID:24478726

  10. Atrial Fibrillation During an Exploration Class Mission

    NASA Technical Reports Server (NTRS)

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

    2010-01-01

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

  11. Sequential Hybrid Procedure for Persistent Atrial Fibrillation

    PubMed Central

    Bulava, Alan; Mokracek, Ales; Hanis, Jiri; Kurfirst, Vojtech; Eisenberger, Martin; Pesl, Ladislav

    2015-01-01

    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

  12. [Risk of thromboembolism in atrial fibrillation].

    PubMed

    Csanádi, Zoltán

    2016-09-01

    Atrial fibrillation is considered as one of the cardiovascular pandemics of our days due to its increasing prevalence and the significant burden on healthcare systems. Management, especially prevention of thromboembolism associated with the arrhythmia is still a challenge even with recently available treatment options. Herein, the author reviews the possibilities of risk stratification and stroke prevention, which are important to all medical professionals who potentially encounter patients with this arrhythmia. Orv. Hetil., 2016, 157(38), 1511-1515. PMID:27640617

  13. Atrial fibrillation pearls and perils of management.

    PubMed Central

    Kudenchuk, P J

    1996-01-01

    Atrial fibrillation, a common arrhythmia, is responsible for considerable cardiovascular morbidity. Its management demands more than antiarrhythmic therapy alone, but must address the causes and consequences of the arrhythmia. Although remediable causes are infrequently found, a thorough search for associated heart disease or its risk factors results in better-informed patient management. Controlling the ventricular response and protecting from thromboembolic complications are important initial goals of therapy and may include the administration of aspirin in younger, low-risk patients. Older patients and those with risk factors for systemic embolism are not adequately protected from stroke complications by aspirin therapy alone. It remains controversial whether all high-risk patients should receive warfarin and at what intensity. Whether and how sinus rhythm should be restored and maintained poses the greatest therapeutic controversy for atrial fibrillation. The mortal risk of antiarrhythmic therapy is substantially greater in patients with evidence of heart failure. In such persons, the risks and benefits of maintaining normal sinus rhythm with antiarrhythmic medications should be weighted carefully. A definitive cure for atrial fibrillation remains elusive, but promising surgical and catheter ablation therapies are being developed. PMID:8686300

  14. Lone atrial fibrillation: Pathologic or not?

    PubMed

    Chambers, Patrick William

    2007-01-01

    Atrial fibrillation risk has been strongly associated with increasing age and visceral obesity. These characteristics are strongly associated with diabetes, decreased heart rate variability, and chronic inflammation. Lone atrial fibrillation (LAF) on the other hand exhibits a predilection for the physically fit and the middle aged, especially males. Given these opposing features it is postulated that pathologic AF is due to cardiac fibrosis and other age related changes while LAF is due to physiologic neurohormonal changes related to autonomic tone, insulin sensitivity, and electrolyte imbalance and that pathologic AF and LAF can be reliably differentiated via an anthropometric approach using weight, height, hip, and waist measurements. An anthropometric study is undertaken from an LAF database to test this hypothesis. Such individuals in addition to being younger and predominantly male appear to be taller with less central adiposity vs. those with pathologic AF. The ramifications of these findings with respect to insulin resistance, sympathetic tone, inflammation and hypertension, often associated with pathologic atrial fibrillation, are discussed. Speculation is drawn about possible etiologic link with mitral valve prolapse, which is commonly encountered in the tall and thin and which shares multiple clinical features with LAF. PMID:17005327

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  16. Ventricular fibrillation and atrial fibrillation are two different beasts

    NASA Astrophysics Data System (ADS)

    Gray, R. A.; Jalife, J.

    1998-03-01

    Although the mechanisms of fibrillation are no doubt multi-faceted, the geometry of the heart may play a major role in the dynamics of wave propagation during fibrillation [A. T. Winfree, Science 266, 1003-1006 (1994)]. The ventricles are thick chambers made up of sheets of parallel muscle fibers with the direction of fibers rotating across the ventricular walls (rotational anisotropy). The thick walls of the ventricles allow reentry to develop transmurally, provided the wavelength is sufficiently small. Depending on the kinetics of heart cells, the dynamics of rotating waves in three dimensions may be fundamentally different than in two dimensions, leading to destabilization of reentry and ventricular fibrillation (VF) in thick ventricles. The atria have an intricate geometry comprised of a thin sheet of cardiac tissue attached to a very complex network of pectinate muscles. The branching geometry of the pectinate muscles may lead to destabilization of two-dimensional reentry via "long-distance" electrical connections giving rise to atrial fibrillation (AF). Therefore, although fibrillation occurs via complex three-dimensional wave propagation in the ventricles and the atria, the underlying mechanisms and factors that sustain VF and AF are probably different.

  17. Atrial fibrillation from the pathologist's perspective.

    PubMed

    Corradi, Domenico

    2014-01-01

    Atrial fibrillation (AF), the most common sustained cardiac arrhythmia encountered in clinical practice, is associated with increased morbidity and mortality. Electrophysiologically, it is characterized by a high rate of asynchronous atrial cell depolarization causing a loss of atrial contractile function and irregular ventricular rates. For a long time, AF was considered as a pure functional disorder without any structural background. Only in recent years, have new mapping and imaging techniques identified atrial locations, which are very often involved in the initiation and maintenance of this supraventricular arrhythmia (i.e. the distal portion of the pulmonary veins and the surrounding atrial myocardium). Morphological analysis of these myocardial sites has demonstrated significant structural remodeling as well as paved the way for further knowledge of AF natural history, pathogenesis, and treatment. This architectural myocardial disarrangement is induced by the arrhythmia itself and the very frequently associated cardiovascular disorders. At the same time, the structural remodeling is also capable of sustaining AF, thereby creating a sort of pathogenetic vicious circle. This review focuses on current understanding about the structural and genetic bases of AF with reference to their classification, pathogenesis, and clinical implications. PMID:24462196

  18. Hypertension and Atrial Fibrillation: Any Change with the New Anticoagulants.

    PubMed

    Ghiadoni, Lorenzo; Taddei, Stefano; Virdis, Agostino

    2014-01-01

    Hypertension and atrial fibrillation are the most common cardiovascular risk factors and clinically significant arrhythmia, respectively. These conditions frequently coexist and their prevalence increases rapidly with aging. Despite several different risk factors and clinical conditions predisposing to hypertension for its high prevalence in the population is still the main risk factor for the development of atrial fibrillation. Several pathophysiologic mechanisms (such as structural changes at the level of left ventricle and or atrium, neurohormonal activation, arterial stiffness, etc.) can contribute to the onset of atrial fibrillation. Some antihypertensive treatments have been shown to contribute to reduce the risk of new-onset atrial fibrillation. Atrial fibrillation is a major risk factor for stroke, which is further increased in the presence of hypertension. For this reason, hypertension is included as a major risk factor in the available models for the risk stratification and the prevention of thromboembolism in patients with atrial fibrillation. In this article we will review the relationship between atrial fibrillation and hypertension, looking at the possible specific indications of the antithrombotic treatment with new classes of anticoagulants in the prevention of thromboembolic events in hypertensive patients with atrial fibrillation.

  19. Novel Interventional Strategies for the Treatment of Atrial Fibrillation

    PubMed Central

    Siontis, Konstantinos C; Oral, Hakan

    2016-01-01

    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

  20. The increasing prevalence of atrial fibrillation among hemodialysis patients.

    PubMed

    Winkelmayer, Wolfgang C; Patrick, Amanda R; Liu, Jun; Brookhart, M Alan; Setoguchi, Soko

    2011-02-01

    A half million Americans have ESRD, which puts them at high risk for cardiovascular disease and poor outcomes. Little is known about the epidemiology of atrial fibrillation among patients with ESRD. We analyzed data from annual cohorts (1992 to 2006) of prevalent hemodialysis patients from the United States Renal Data System. In each cohort, we searched 1 year of medical claims for relevant diagnosis codes to determine the prevalence of atrial fibrillation. Among 2.5 million patient observations, 7.7% had atrial fibrillation, with the prevalence increasing 3-fold from 3.5% (1992) to 10.7% (2006). The number of affected patients increased from 3620 to 23,893 (6.6-fold) during this period. Older age, male gender, and several comorbid conditions were associated with increased risk for atrial fibrillation. Compared with otherwise similar Caucasians, the prevalence of atrial fibrillation rates was substantially lower for blacks, Asians, and Native Americans. One-year mortality was twice as high among hemodialysis patients with atrial fibrillation compared with those without (39% versus 19%), and this increased risk was constant during the 15 years of the study. In conclusion, the prevalence of diagnosed atrial fibrillation among patients receiving hemodialysis in the United States is increasing, varies by race, and remains associated with substantially increased mortality. Identifying potentially modifiable risk factors for incident atrial fibrillation requires further investigation.

  1. Atrial Electrophysiological Remodeling and Fibrillation in Heart Failure

    PubMed Central

    Pandit, Sandeep V.; Workman, Antony J.

    2016-01-01

    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

  2. Vernakalant. Too dangerous in atrial fibrillation.

    PubMed

    2012-05-01

    The usual aim of treatment for patients with symptomatic paroxysmal or recent-onset atrial fibrillation, including after cardiac surgery, is to slow the heart rate. Electrical and drug (amiodarone) cardioversion are other options. Vernakalant, an antiarrhythmic drug, has been authorised in the European Union for rapid reduction of recent-onset atrial fibrillation. It is only available in an injectable form. Vernakalant has not been compared in clinical trials with treatments slowing the heart rate, or with electrical cardioversion. The only available comparison with another antiarrhythmic agent is a clinical pharmacology study versus amiodarone, a slow-acting drug, based on the rate of cardioversion at 90 minutes in 240 patients. As expected, given the brief observation period, the rate was significantly higher with vernakalant (51.7% versus 5.2%). During clinical evaluation, 6 deaths occurred in the vernakalant groups versus none in the other groups (placebo or amiodarone). The main adverse effects of vernakalant are cardiac arrhythmias (ventricular arrhythmia, torsades de pointes, bradycardia) and severe hypotension. Altered taste, sneezing, paraesthesia, nausea and pruritus were frequent, and respiratory and neuropsychological effects were also reported. A trial in atrial flutter was interrupted when cases of cardiogenic shock occurred. Interactions are to be expected with drugs that prolong the QT interval, and also with drugs that lower the heart rate or the blood potassium concentration. In practice, it is better to continue to use amiodarone for drug cardioversion and to avoid using vernakalant. PMID:22827000

  3. Global burden of atrial fibrillation in developed and developing nations.

    PubMed

    Chugh, Sumeet S; Roth, Gregory A; Gillum, Richard F; Mensah, George A

    2014-03-01

    Atrial fibrillation is the most common heart rhythm disorder in the world, with major public health impact especially due to increased risk of stroke and hospitalizations. The recently published results on epidemiology of atrial fibrillation from the Global Burden of Diseases, Injuries, and Risk Factors Study confirm the existence of a significant and progressive worldwide increase in the burden of atrial fibrillation. However, there appears to be regional variation in both the burden of atrial fibrillation and availability of epidemiological data regarding this condition. In this review, the authors identify issues that are unique to the developed versus developing regions and outline a road map for possible approaches to surveillance, management, and prevention of atrial fibrillation at the global level.

  4. Connexin Gene Transfer Preserves Conduction Velocity and Prevents Atrial Fibrillation

    PubMed Central

    Igarashi, Tomonori; Finet, J. Emanuel; Takeuchi, Ayano; Fujino, Yoshihisa; Strom, Maria; Greener, Ian D.; Rosenbaum, David S.; Donahue, J. Kevin

    2011-01-01

    Background Several lines of evidence have suggested that maintenance of atrial fibrillation (AF) depends on reentrant mechanisms. Maintenance of reentry necessitates a sufficiently short refractory period and/or delayed conduction, and AF has been associated with both alterations. Fibrosis, cellular dysfunction and gap junction protein alterations occur in AF and cause conduction delay. We performed this study to test the hypothesis that gap junction protein overexpression would improve conduction and prevent AF. Methods and Results Thirty Yorkshire swine were randomized into 2 groups (sinus rhythm (SR) and AF), and within each group into 3 subgroups: sham-operated control, gene therapy with adenovirus expressing connexin (Cx) 40 and Cx43 (n=5 per subgroup). All animals had epicardial gene painting; the AF group had burst atrial pacing. All animals underwent terminal study 7 days after gene transfer. SR animals had strong transgene expression but no atrial conduction changes. In AF animals, controls had reduced and lateralized Cx43 expression, and Cx43 gene transfer restored expression and cellular location to SR control levels. In the AF group, both Cx40 and Cx43 gene transfer improved conduction and reduced AF relative to controls. Conclusions Connexin gene therapy preserved atrial conduction and prevented AF. PMID:22158756

  5. Propofol effects on atrial fibrillation wavefront delays.

    PubMed

    Cervigón, Raquel; Moreno, Javier; Millet, José; Pérez-Villacastín, Julián; Castells, Francisco

    2010-08-01

    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.

  6. Minimally invasive surgery for atrial fibrillation.

    PubMed

    Lancaster, Timothy S; Melby, Spencer J; Damiano, Ralph J

    2016-04-01

    The surgical treatment of atrial fibrillation (AF) has been revolutionized over the past two decades through surgical innovation and improvements in endoscopic imaging, ablation technology, and surgical instrumentation. These advances have prompted the development of the less complex and less morbid Cox-Maze IV procedure, and have allowed its adaptation to a minimally invasive right mini-thoracotomy approach that can be used in stand-alone AF ablation and in patients undergoing concomitant mitral and tricuspid valve surgery. Other minimally invasive ablation techniques have been developed for stand-alone AF ablation, including video-assisted pulmonary vein isolation, extended left atrial lesion sets, and a hybrid approach. This review will discuss the tools, techniques, and outcomes of minimally invasive surgical procedures currently being practiced for AF ablation.

  7. NASA's First Atrial Fibrillation Case - Deke Slayton

    NASA Technical Reports Server (NTRS)

    Tarver, William J.

    2010-01-01

    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.

  8. Science Linking Pulmonary Veins and Atrial Fibrillation

    PubMed Central

    Mahida, Saagar; Sacher, Frederic; Derval, Nicolas; Berte, Benjamin; Yamashita, Seigo; Hooks, Darren; Denis, Arnaud; Amraoui, Sana; Hocini, Meleze; Haissaguerre, Michel; Jais, Pierre

    2015-01-01

    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

  9. Minimally Invasive Atrial Fibrillation Surgery: Hybrid Approach

    PubMed Central

    Beller, Jared P.; Downs, Emily A.; Ailawadi, Gorav

    2016-01-01

    Atrial fibrillation is a challenging pathologic process. There continues to be a great need for the development of a reproducible, durable cure when medical management has failed. An effective, minimally invasive, sternal-sparing intervention without the need for cardiopulmonary bypass is a promising treatment approach. In this article, we describe a hybrid technique being refined at our center that combines a thoracoscopic epicardial surgical approach with an endocardial catheter-based procedure. We also discuss our results and review the literature describing this unique treatment approach. PMID:27127561

  10. Cardiometabolic risk factors and atrial fibrillation.

    PubMed

    Menezes, Arthur R; Lavie, Carl J; Dinicolantonio, James J; O'Keefe, James; Morin, Daniel P; Khatib, Sammy; Abi-Samra, Freddy M; Messerli, Franz H; Milani, Richard V

    2013-01-01

    Atrial fibrillation (AF) is the most common arrhythmia worldwide; it is a significant risk factor for stroke and embolization, and has an impact on cardiac function. Despite its impact on morbidity and mortality, our understanding of the etiology and pathophysiology of this disease process is still incomplete. Over the past several decades, there has been evidence to suggest that AF has a significant correlation with metabolic syndrome (MetS). Furthermore, AF appears to be more closely related to specific components of MetS compared with others. This article provides an overview of the various components of MetS and their impact on AF. PMID:24448257

  11. The Epidemiology of Atrial Fibrillation and Stroke.

    PubMed

    Pistoia, Francesca; Sacco, Simona; Tiseo, Cindy; Degan, Diana; Ornello, Raffaele; Carolei, Antonio

    2016-05-01

    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. PMID:27150174

  12. Silent Atrial Fibrillation: Definition, Clarification, and Unanswered Issues.

    PubMed

    Kennedy, Harold L

    2015-11-01

    Silent or subclinical asymptomatic atrial fibrillation has currently gained wide interest in the epidemiologic, neurologic and cardiovascular communities. The association of brief episodes of paroxysmal atrial fibrillation or surrogate atrial arrhythmias which predict future clinical adverse events have been established. Nevertheless there exists a confounding array of definitions to indicate its presence without discrete indication of which populations should be examined. Moreover the term "atrial fibrillation burden" (AFB) has emerged from such studies with a plethora of descriptions to prognosticate both arrhythmic and clinical adverse events. This presentation suggests clarification of diagnostic definitions associated with silent atrial fibrillation, and a more precise description of AFB. It examines the populations across the current disease and cardiovascular invasive therapeutic spectrum that lead to both silent atrial fibrillation and AFB. It describes the diagnostic methods of arrhythmia detection utilizing the surface ECG, subcutaneous ECG or intra-cardiac devices and their relationship in seeking meaningful arrhythmic markers of silent atrial fibrillation. Whereas a wide range of clinical risk factors of silent atrial fibrillation have been validated in the literature, there is an ongoing search for those arrhythmic risk factors that precisely identify and prognosticate outcome events in diverse populations at risk of atrial fibrillation and its complications. This presentation identifies this chaos, and focuses attention on the issues to be addressed to facilitate descriptive and comparative scientific studies in the future. It is a call to action specifically to the medical arrhythmic community and its specialty societies (i.e., ISHNE, HRS, EHRA) to begin a quest to unravel the arrhythmic quagmire associated with "silent atrial fibrillation."

  13. P-wave Variability and Atrial Fibrillation

    PubMed Central

    Censi, Federica; Corazza, Ivan; Reggiani, Elisa; Calcagnini, Giovanni; Mattei, Eugenio; Triventi, Michele; Boriani, Giuseppe

    2016-01-01

    The analysis of P-wave template has been widely used to extract indices of Atrial Fibrillation (AF) risk stratification. The aim of this paper was to assess the potential of the analysis of the P-wave variability over time in patients suffering from atrial fibrillation. P-wave features extracted from P-wave template together with novel indices of P-wave variability have been estimated in a population of patients suffering from persistent AF and compared to those extracted from control subjects. We quantify the P-wave variability over time using three algorithms and we extracted three novel indices: one based on the cross-correlation coefficients among the P-waves (Cross-Correlation Index, CCI), one associated to variation in amplitude of the P-waves (Amplitude Dispersion Index, ADI), one sensible to the phase shift among P-waves (Warping Index, WI). The control group resulted to be characterized by shorter P-wave duration and by a less amount of fragmentation and variability, respect to AF patients. The parameter CCI shows the highest sensitivity (97.3%) and a good specificity (95%). PMID:27225709

  14. P-wave Variability and Atrial Fibrillation.

    PubMed

    Censi, Federica; Corazza, Ivan; Reggiani, Elisa; Calcagnini, Giovanni; Mattei, Eugenio; Triventi, Michele; Boriani, Giuseppe

    2016-01-01

    The analysis of P-wave template has been widely used to extract indices of Atrial Fibrillation (AF) risk stratification. The aim of this paper was to assess the potential of the analysis of the P-wave variability over time in patients suffering from atrial fibrillation. P-wave features extracted from P-wave template together with novel indices of P-wave variability have been estimated in a population of patients suffering from persistent AF and compared to those extracted from control subjects. We quantify the P-wave variability over time using three algorithms and we extracted three novel indices: one based on the cross-correlation coefficients among the P-waves (Cross-Correlation Index, CCI), one associated to variation in amplitude of the P-waves (Amplitude Dispersion Index, ADI), one sensible to the phase shift among P-waves (Warping Index, WI). The control group resulted to be characterized by shorter P-wave duration and by a less amount of fragmentation and variability, respect to AF patients. The parameter CCI shows the highest sensitivity (97.3%) and a good specificity (95%). PMID:27225709

  15. Comparative study of atrial fibrillation and AV conduction in mammals.

    PubMed

    Meijler, F L; van der Tweel, I

    1987-01-01

    Atrial fibrillation is one of the most common cardiac arrhythmias in humans. It also occurs quite frequently in dogs and horses. Comparative study of this arrhythmia may contribute to better understanding of the pathophysiological mechanisms involved. In this study, we present a quantitative analysis of atrial fibrillation in humans, dogs, horses, and in a kangaroo, making use of histograms and serial autocorrelograms of the ventricular rhythm with and without digitalis medication. Increase in the size of the animal and thus in the size of the heart is accompanied by a decrease in ventricular rate. The ventricular rhythm was random in the dog, kangaroo, and man, but periodicity was present in the horse. Digitalis decreased the ventricular rate in all species studied and enforced the periodicity in the horse. The differences in the atrial excitation process, atrioventricular (AV) conduction, and ventricular behavior between the four species studied are small when compared with the differences in their heart size. We conclude that in evolution, as far as the heart is concerned, cell size and morphology probably prevail over cell-function.

  16. Atrial fibrillation: effects beyond the atrium?

    PubMed

    Wijesurendra, Rohan S; Casadei, Barbara

    2015-03-01

    Atrial fibrillation (AF) is the most common sustained clinical arrhythmia and is associated with significant morbidity, mostly secondary to heart failure and stroke, and an estimated two-fold increase in premature death. Efforts to increase our understanding of AF and its complications have focused on unravelling the mechanisms of electrical and structural remodelling of the atrial myocardium. Yet, it is increasingly recognized that AF is more than an atrial disease, being associated with systemic inflammation, endothelial dysfunction, and adverse effects on the structure and function of the left ventricular myocardium that may be prognostically important. Here, we review the molecular and in vivo evidence that underpins current knowledge regarding the effects of human or experimental AF on the ventricular myocardium. Potential mechanisms are explored including diffuse ventricular fibrosis, focal myocardial scarring, and impaired myocardial perfusion and perfusion reserve. The complex relationship between AF, systemic inflammation, as well as endothelial/microvascular dysfunction and the effects of AF on ventricular calcium handling and oxidative stress are also addressed. Finally, consideration is given to the clinical implications of these observations and concepts, with particular reference to rate vs. rhythm control.

  17. Atrial Cardiopathy: A Broadened Concept of Left Atrial Thromboembolism Beyond Atrial Fibrillation

    PubMed Central

    Kamel, Hooman; Okin, Peter M.; Longstreth, W. T.; Elkind, Mitchell S.V.; Soliman, Elsayed Z.

    2016-01-01

    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

  18. Computational models of atrial cellular electrophysiology and calcium handling, and their role in atrial fibrillation.

    PubMed

    Heijman, Jordi; Erfanian Abdoust, Pegah; Voigt, Niels; Nattel, Stanley; Dobrev, Dobromir

    2016-02-01

    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

  19. [Obesity as a risk factor for atrial fibrillation].

    PubMed

    Duraj, Iwona; Broncel, Marlena

    2016-01-01

    Atrial fibrillation (AF) and obesity is a growing problem of public health both in Poland and in the whole world. AF risk factors may be summarized as elderliness, male sex, smoking, hypertension, diabetes, obesity, coronary heart disease, heart failure, valvular heart disease, cardiac surgery. Once obesity is an independent, potentially modifiable risk factor for AF. The connection between obesity and atrial fibrillation is very up-to-date because of incremental prevalence, almost epidemic of obesity in the whole world. The probability of AF among obese patients increases with concomitant obstructive sleep apnea. Regardless many researches it hasn't been assessed yet how obesity itself predisposes to AF. It could be an effect of change in the atrial anatomy, the rise of atrial pressure, mechanical stretch, interstitial atrial fibrosis and disruption of atrial electric integrity. A great role is ascribed to inflammation, especially proinflammatory cytokines increased by adipocites of left atrial epicardial adiposity. PMID:26891428

  20. [Obesity as a risk factor for atrial fibrillation].

    PubMed

    Duraj, Iwona; Broncel, Marlena

    2016-01-01

    Atrial fibrillation (AF) and obesity is a growing problem of public health both in Poland and in the whole world. AF risk factors may be summarized as elderliness, male sex, smoking, hypertension, diabetes, obesity, coronary heart disease, heart failure, valvular heart disease, cardiac surgery. Once obesity is an independent, potentially modifiable risk factor for AF. The connection between obesity and atrial fibrillation is very up-to-date because of incremental prevalence, almost epidemic of obesity in the whole world. The probability of AF among obese patients increases with concomitant obstructive sleep apnea. Regardless many researches it hasn't been assessed yet how obesity itself predisposes to AF. It could be an effect of change in the atrial anatomy, the rise of atrial pressure, mechanical stretch, interstitial atrial fibrosis and disruption of atrial electric integrity. A great role is ascribed to inflammation, especially proinflammatory cytokines increased by adipocites of left atrial epicardial adiposity.

  1. [Prophylaxis of thromboembolism in atrial fibrillation: new oral anticoagulants and left atrial appendage closure].

    PubMed

    Zeus, Tobias; Kelm, Malte; Bode, Christoph

    2015-08-01

    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. PMID:26261929

  2. Relationship between two arrhythmias: sinus node dysfunction and atrial fibrillation.

    PubMed

    Zhao, Jun; Liu, Tong; Li, Guangping

    2014-05-01

    We reviewed recent advancements in the relationship between sinus node dysfunction (SND) and atrial fibrillation (AF) and propose some underlying mechanisms in regard to ion and molecular aspects. The amount of clinical and animal experiments have proven the structural and electrophysiological remodeling of sinoatrial node (SAN) and atrium may be related significantly between SND and AF. Atrial remodeling was often related to RAS activation. RAS inhibitors and statin, which resist in atrial fibrosis, may be novel strategies to prevent or treat both SND and AF. Besides, funny current (If) and Ca(2+) clock mainly contributing to the SAN automaticity may be another link between SND and AF. Gap junctions such as Cx40, Cx43 and Cx45 were proven to participate in both automaticity and conductivity of electrical impulses in SAN and atrial tissue, which was accepted as another link between SND and AF. Common genetic mutations such as the emerin gene, SCN5A gene and HCN4 gene mutation were also the mechanism for the correlation between SND and AF.

  3. Dronedarone for the treatment of atrial fibrillation and atrial flutter.

    PubMed

    Maund, E; McKenna, C; Sarowar, M; Fox, D; Stevenson, M; Pepper, C; Palmer, S; Woolacott, N

    2010-10-01

    This paper presents a summary of the evidence review group (ERG) report on the clinical effectiveness and cost-effectiveness of dronedarone for the treatment of atrial fibrillation (AF) or atrial flutter based upon a review of the manufacturer's submission to the National Institute for Health and Clinical Excellence (NICE) as part of the single technology appraisal process. The population considered in the submission were adult clinically stable patients with a recent history of or current non-permanent AF. Comparators were the current available anti-arrhythmic drugs: class 1c agents (flecainide and propafenone), sotalol and amiodarone. Outcomes were AF recurrence, all-cause mortality, stroke, treatment discontinuations (due to any cause or due to adverse events) and serious adverse events. The main evidence came from four phase III randomised controlled trials, direct and indirect meta-analyses from a systematic review, and a synthesis of the direct and indirect evidence using a mixed-treatment comparison. Overall, the results from the different synthesis approaches showed that the odds of AF recurrence appeared statistically significantly lower with dronedarone and other anti-arrhythmic drugs than with non-active control, and that the odds of AF recurrence are statistically significantly higher for dronedarone than for amiodarone. However, the results for outcomes of all-cause mortality, stroke and treatment discontinuations and serious adverse events were all uncertain. A discrete event simulation model was used to evaluate dronedarone versus antiarrhythmic drugs and standard therapy alone. The incremental cost-effectiveness ratio of dronedarone was relatively robust and less than 20,000 pounds per quality-adjusted life-year. Exploratory work undertaken by the ERG identified that the main drivers of cost-effectiveness were the benefits assigned to dronedarone for all-cause mortality and stroke. Dronedarone is not cost-effective relative to its comparators when

  4. [Esophageal echocardiography in patients with cerebrovascular stroke and atrial fibrillation].

    PubMed

    Chlumský, J; Bojar, M; Sváb, P; Holá, D

    1997-04-01

    Atrial fibrillation is an important risk factor of embolization into the CNS. Thus affected patients should receive permanent anticoagulant therapy. Oesophageal echocardiography (TEE) can help our decision in patients with relative contraindications of anticoagulant therapy. TEE was performed in 52 patients with atrial fibrillation and cerebrovascular attack (CMP) with an ischaemic aetiology. Transthoracic echocardiography did not reveal the source of embolization. In 10% patients a thrombus was found in the appendage of the left atrium, in another 9% patients a spontaneous echocontrast was found in the left atrium (prethrombotic condition) and in 5% patients an open foramen ovale. The results indicate the highly probable etiology of embolization in patients with cerebrovascular attacks and atrial fibrillation. This supports the recommendation of absolute indication of anticoagulant treatment in patients with cerebrovascular attacks and atrial fibrillation.

  5. Apixaban for the prevention of stroke in atrial fibrillation.

    PubMed

    Littrell, Rachel; Flaker, Greg

    2012-02-01

    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. PMID:22292869

  6. Atrial Fibrillation, Cognitive Decline And Dementia

    PubMed Central

    Alonso, Alvaro; Arenas de Larriva, Antonio P.

    2016-01-01

    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

  7. Bridging the gender gap in atrial fibrillation.

    PubMed

    Oza, Nishaki Mehta; Baveja, Swati; Tedrow, Usha

    2015-03-01

    Women have a similar lifetime prevalence of non-valvular atrial fibrillation (NVAF) compared with that of men. Given the significant morbidity and potential mortality associated with NVAF, it is crucial to understand gender differences with NVAF. Women can be more symptomatic than men. Despite a higher baseline stroke risk, they are less likely to be on anticoagulation. Women have a greater risk of thromboembolism and a similar rate of bleeding risk compared with men on anticoagulation. Initial experience suggests that novel oral anticoagulants have similar safety and efficacy profile in men and women. Although women can have more adverse reactions from antiarrhythmic therapies, they are often referred later than men for ablation. As a group, a mitigating factor in ablation referral is that women also have a higher incidence of procedural complications from catheter ablation. This review summarizes the available literature highlighting significant gender-based differences and also highlights areas for research to improve NVAF outcomes in women. PMID:25586881

  8. Individualising Anticoagulant Therapy in Atrial Fibrillation Patients.

    PubMed

    Alings, Marco

    2016-08-01

    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

  9. New anthyarrhythmic drugs for atrial fibrillation.

    PubMed

    Matassini, Maria Vittoria; Guerra, Federico; Scappini, Lorena; Scappini, Loren; Urbinati, Alessia; Capucci, Alessandro

    2015-01-01

    Atrial fibrillation (AF) is a common arrhythmia associated with increased mortality and morbidity. Different studies have shown no significant difference between rhythm and rate control strategies in terms of mortality. Moreover, the use of antiarrhythmic drugs is afflicted by cardiac and extracardiac toxicity and related costs of hospitalization. Nevertheless, some patients require a rhythm-control strategy and new anti-AF agents are being sought. Only few novel agents showed promising results in term of efficacy and safety. Dronedarone and vernakalant are two of these compounds, respectively introduced for the chronic and acute rhythm control of AF. This article will review pharmacology and clinical evidence on the use of dronedarone and vernakalant and will mention currently investigated new antiarrhythmic drugs. PMID:26631497

  10. Individualising Anticoagulant Therapy in Atrial Fibrillation Patients

    PubMed Central

    2016-01-01

    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

  11. Individualising Anticoagulant Therapy in Atrial Fibrillation Patients

    PubMed Central

    2016-01-01

    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.

  12. The current approach of atrial fibrillation management

    PubMed Central

    Amin, Anish; Houmsse, Aseel; Ishola, Abiodun; Tyler, Jaret; Houmsse, Mahmoud

    2016-01-01

    Atrial fibrillation (AF) is the most commonly encountered arrhythmia in clinical practice. Aging populations coupled with improved outcomes for many chronic medical conditions has led to increases in AF diagnoses. AF is also known to be associated with an increased risk of adverse events such as transient ischemic attack, ischemic stroke, systemic embolism, and death. This association is enhanced in select populations with preexisting comorbid conditions such as chronic heart failure. The aim of this review is to highlight the advances in the field of cardiology in the management of AF in both acute and long-term settings. We will also review the evolution of anticoagulation management over the past few years and landmark trials in the development of novel oral anticoagulants (NOACs), reversal agents for new NOACs, nonpharmacological options to anticoagulation therapy, and the role of implantable loop recorder in AF management. PMID:26955600

  13. Serum Soluble Semaphorin 4D is Associated with Left Atrial Diameter in Patients with Atrial Fibrillation

    PubMed Central

    Xiang, Li; You, Tao; Chen, Jianchang; Xu, Weiting; Jiao, Yang

    2015-01-01

    Background The aim of this study was to evaluate the serum soluble semaphorin 4D (sSema4D) in patients with atrial fibrillation and to investigate the relationship of serum sSema4D with left atrial diameter (LAD). Material/Methods We studied a total of 113 patients who were subdivided into paroxysmal and non-paroxysmal (included persistent and permanent) atrial fibrillation groups, respectively. Another 55 subjects without atrial fibrillation were enrolled as the healthy control group. Serum levels of soluble semaphorin 4D (Sema4D) were measured in all subjects using the enzyme-labeled immunosorbent assay method. We also evaluated the coagulation parameters and left atrial diameters. Results Patients with paroxysmal and non-paroxysmal atrial fibrillation had significantly higher sSema4D level compared with controls (8.50±2.19 ng/mL and 9.30±2.28 ng/mL vs. 6.56±1.27 ng/ml, P<0.05). Serum sSema4D concentrations were elevated in patients with non-paroxysmal atrial fibrillation compared to those with paroxysmal atrial fibrillation (P<0.001). The level of sSema4D was positively correlated with LAD (r=0.606, P<0.001). Multivariate logistic regression analysis revealed that serum sSema4D, LAD, male sex, heart rate, hypertension, and coronary artery disease were associated with atrial fibrillation (P<0.05). Conclusions Serum sSema4D levels are increased in patients with atrial fibrillation and are independently associated with atrial remodeling. PMID:26417899

  14. Inherited Structural Heart Diseases With Potential Atrial Fibrillation Occurrence.

    PubMed

    Manuguerra, Roberta; Callegari, Sergio; Corradi, Domenico

    2016-02-01

    Inherited cardiac diseases inducing structural remodeling of the myocardium sometimes develop arrhythmias of various kinds. Among these rhythm disturbances, atrial fibrillation is well known to frequently worsen the prognosis of the primary disorder by increasing morbidity and mortality, especially because of a higher rate of heart failure. In this manuscript, we have reviewed the literature on the most important inherited structural cardiac diseases in whose clinical history atrial fibrillation may occur fairly often.

  15. Termination of acute wide QRS complex atrial fibrillation with ibutilide.

    PubMed

    Sobel, R M; Dhruva, N N

    2000-07-01

    Ibutilide is a Vaughan-Williams class III antiarrhythmic agent approved for chemical cardioversion of acute onset atrial fibrillation/flutter. Emergency physicians rarely use ibutilide despite its proven clinical value. We report a case of successful chemical cardioversion using ibutilide in a patient with atrial fibrillation and delayed ventricular depolarization (wide QRS complex). We recommend that ibutilide be considered for wider use in the emergency department and that further studies be conducted.

  16. Relation of porphyria to atrial fibrillation.

    PubMed

    Dhoble, Abhijeet; Patel, Mehul B; Abdelmoneim, Sahar S; Puttarajappa, Chethan; Abela, George S; Bhatt, Deepak L; Thakur, Ranjan K

    2009-08-01

    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.

  17. Current hot potatoes in atrial fibrillation ablation.

    PubMed

    Roten, Laurent; Derval, Nicolas; Pascale, Patrizio; Scherr, Daniel; Komatsu, Yuki; Shah, Ashok; Ramoul, Khaled; Denis, Arnaud; Sacher, Frédéric; Hocini, Mélèze; Haïssaguerre, Michel; Jaïs, Pierre

    2012-11-01

    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

  18. Atrial Fibrillation and SCN5A Variants

    PubMed Central

    Savio-Galimberti, Eleonora; Darbar, Dawood

    2014-01-01

    Although atrial fibrillation (AF) is clinically and genetically a highly heterogeneous disease, recent studies suggest that the arrhythmia may arise because of interactions between genetic and acquired risk factors – the so called “double-hit” hypothesis. Genome-wide association studies have identified common AF susceptibility loci, and linkage analysis and candidate gene approaches have identified mutations in genes that encode for cardiac ion channels and signaling proteins; however, most of the heritability of AF still remains unexplained. The voltage-dependent cardiac sodium channel, encoded by SCN5A, conducts the main cardiac inward sodium current (INa) and is responsible for the upstroke of the atrial action potential. Mutations in SCN5A, which encodes the α-subunit of the NaV1.5 channel, have been linked with increased susceptibility to not only AF but also ventricular arrhythmias (long QT syndrome, Brugada syndrome), progressive cardiac conduction disease, and overlap syndromes with mixed arrhythmia phenotypes. Over the last decade, functional characterization of SCN5A mutations by expressing the channel in heterologous expression systems and applying cellular electrophysiological techniques has not only advanced our understanding of molecular mechanisms of AF but also potentially identified a mechanism-based approach to treating this common and morbid condition. PMID:25484998

  19. Estimating Effective Dose from Phantom Dose Measurements in Atrial Fibrillation Ablation Procedures and Comparison of MOSFET and TLD Detectors in a Small Animal Dosimetry Setting

    NASA Astrophysics Data System (ADS)

    Anderson-Evans, Colin David

    Two different studies will be presented in this work. The first involves the calculation of effective dose from a phantom study which simulates an atrial fibrillation (AF) ablation procedure. The second involves the validation of metal-oxide semiconducting field effect transistors (MOSFET) for small animal dosimetry applications as well as improved characterization of the animal irradiators on Duke University's campus. Atrial Fibrillation is an ever increasing health risk in the United States. The most common type of cardiac arrhythmia, AF is associated with increased mortality and ischemic cerebrovascular events. Managing AF can include, among other treatments, an interventional procedure called catheter ablation. The procedure involves the use of biplane fluoroscopy during which a patient can be exposed to radiation for as much as two hours or more. The deleterious effects of radiation become a concern when dealing with long fluoroscopy times, and because the AF ablation procedure is elective, it makes relating the risks of radiation ever more essential. This study hopes to quantify the risk through the derivation of dose conversion coefficients (DCCs) from the dose-area product (DAP) with the intent that DCCs can be used to provide estimates of effective dose (ED) for typical AF ablation procedures. A bi-plane fluoroscopic and angiographic system was used for the simulated AF ablation procedures. For acquisition of organ dose measurements, 20 diagnostic MOSFET detectors were placed at selected organs in a male anthropomorphic phantom, and these detectors were attached to 4 bias supplies to obtain organ dose readings. The DAP was recorded from the system console and independently validated with an ionization chamber and radiochromic film. Bi-plane fluoroscopy was performed on the phantom for 10 minutes to acquire the dose rate for each organ, and the average clinical procedure time was multiplied by each organ dose rate to obtain individual organ doses. The

  20. Electrogram Morphology Recurrence Patterns during Atrial Fibrillation

    PubMed Central

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

    2014-01-01

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

  1. Atrial fibrillation: mechanisms, therapeutics, and future directions.

    PubMed

    Pellman, Jason; Sheikh, Farah

    2015-04-01

    Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia, affecting 1% to 2% of the general population. It is characterized by rapid and disorganized atrial activation leading to impaired atrial function, which can be diagnosed on an EKG by lack of a P-wave and irregular QRS complexes. AF is associated with increased morbidity and mortality and is a risk factor for embolic stroke and worsening heart failure. Current research on AF support and explore the hypothesis that initiation and maintenance of AF require pathophysiological remodeling of the atria, either specifically as in lone AF or secondary to other heart disease as in heart failure-associated AF. Remodeling in AF can be grouped into three categories that include: (i) electrical remodeling, which includes modulation of L-type Ca(2+) 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

  2. Estimating Effective Dose from Phantom Dose Measurements in Atrial Fibrillation Ablation Procedures and Comparison of MOSFET and TLD Detectors in a Small Animal Dosimetry Setting

    NASA Astrophysics Data System (ADS)

    Anderson-Evans, Colin David

    Two different studies will be presented in this work. The first involves the calculation of effective dose from a phantom study which simulates an atrial fibrillation (AF) ablation procedure. The second involves the validation of metal-oxide semiconducting field effect transistors (MOSFET) for small animal dosimetry applications as well as improved characterization of the animal irradiators on Duke University's campus. Atrial Fibrillation is an ever increasing health risk in the United States. The most common type of cardiac arrhythmia, AF is associated with increased mortality and ischemic cerebrovascular events. Managing AF can include, among other treatments, an interventional procedure called catheter ablation. The procedure involves the use of biplane fluoroscopy during which a patient can be exposed to radiation for as much as two hours or more. The deleterious effects of radiation become a concern when dealing with long fluoroscopy times, and because the AF ablation procedure is elective, it makes relating the risks of radiation ever more essential. This study hopes to quantify the risk through the derivation of dose conversion coefficients (DCCs) from the dose-area product (DAP) with the intent that DCCs can be used to provide estimates of effective dose (ED) for typical AF ablation procedures. A bi-plane fluoroscopic and angiographic system was used for the simulated AF ablation procedures. For acquisition of organ dose measurements, 20 diagnostic MOSFET detectors were placed at selected organs in a male anthropomorphic phantom, and these detectors were attached to 4 bias supplies to obtain organ dose readings. The DAP was recorded from the system console and independently validated with an ionization chamber and radiochromic film. Bi-plane fluoroscopy was performed on the phantom for 10 minutes to acquire the dose rate for each organ, and the average clinical procedure time was multiplied by each organ dose rate to obtain individual organ doses. The

  3. Detection of atrial-flutter and atrial-fibrillation waveforms by fetal magnetocardiogram.

    PubMed

    Kandori, A; Hosono, T; Kanagawa, T; Miyashita, S; Chiba, Y; Murakami, M; Miyashita, T; Tsukada, K

    2002-03-01

    Two cases of fetal tachycardia are reported: atrial flutter and fibrillation. The waveforms from each case were detected by fetal magnetocardiograms (FMCGs) using a 64-channel superconducting quantum interference device (SQUID) system. Because the magnitude of supraventricular arrhythmia signals is very weak, two subtraction methods were used to detect the fetal MCG waveforms: subtraction of the maternal MCG signal, and subtraction of the fetal ORS complex signal. It was found that atrial-flutter waveforms showed a cyclic pattern and that atrial-fibrillation waveforms showed f-waves with a random atrial rhythm. Fast Fourier transform analysis determined the main frequency of the atrial flutter to be about 7Hz, and the frequency distribution of atrial fibrillation consisted of small, broad peaks. To visualise the current pattern, current-arrow maps, which simplify the observation of pseudo-current patterns in fetal hearts, of the averaged atrial flutter and fibrillation waveforms were produced. The map of the atrial flutter had a circular pattern, indicating a re-entry circuit, and the map of the atrial fibrillation indicated one wavelet, which was produced by a micro-re-entry circuit. It is thus concluded that an FMCG can detect supraventricular arrhythmia, which can be characterised by re-entry circuits, in fetuses. PMID:12043803

  4. Atrial fibrillation in inherited cardiac channelopathies: From mechanisms to management.

    PubMed

    Enriquez, Andres; Antzelevitch, Charles; Bismah, Verdah; Baranchuk, Adrian

    2016-09-01

    Atrial fibrillation (AF) is prevalent in cardiac channelopathies and may be the presenting feature in some patients. The pathogenesis is related to the primary ion channel dysfunction in atrial myocytes that affects atrial conduction or repolarization. The development of AF is associated with adverse outcomes, and its management is challenging in these patients. In this article we review the current information on the prevalence, risk factors, pathophysiology, and treatment of AF in specific cardiac channelopathies. PMID:27291509

  5. Cost effectiveness of therapies for atrial fibrillation. A review.

    PubMed

    Teng, M P; Catherwood, L E; Melby, D P

    2000-10-01

    Atrial fibrillation is the most common supraventricular tachyarrhythmia encountered in clinical practice, affecting over 5% of persons over the age of 65 years. A common pathophysiological mechanism for arrhythmia development is atrial distention and fibrosis induced by hypertension, coronary artery disease or ventricular dysfunction. Less frequently, atrial fibrillation is caused by mitral stenosis or other provocative factors such as thyrotoxicosis, pericarditis or alcohol intoxication. Depending on the extent of associated cardiovascular disease, atrial fibrillation may produce haemodynamic compromise, or symptoms such as palpitations, fatigue, chest pain or dyspnoea. Arrhythmia-induced atrial stasis can precipitate clot formation and the potential for subsequent thromboembolism. Comprehensive management of atrial fibrillation requires a multifaceted approach directed at controlling symptoms, protecting the patient from ischaemic stroke or peripheral embolism and possible conversion to or maintenance of sinus rhythm. Numerous randomised trials have demonstrated the efficacy of warfarin--and less so aspirin (acetylsalicylic acid)--in reducing the risk of embolic events. Furthermore, therapeutic strategies exist that can favourably modify symptoms by restoring and maintaining sinus rhythm with cardioversion and antiarrhythmic prophylaxis. However, the risks and benefits of various treatments is highly dependent on patient-specific features, emphasising the need for an individualised approach. This article reviews the findings of cost-effectiveness studies published over the past decade that have evaluated different components of treatment strategies for atrial fibrillation. These studies demonstrate the economic attractiveness of acute management options, long term warfarin prophylaxis, telemetry-guided initiation of antiarrhythmic therapy, approaches to restore and maintain sinus rhythm, and the potential role of transoesophageal echocardiographic screening for

  6. Left atrial appendage occlusion in atrial fibrillation after intracranial hemorrhage

    PubMed Central

    Horstmann, Solveig; Zugck, Christian; Krumsdorf, Ulrike; Rizos, Timolaos; Rauch, Geraldine; Geis, Nicolas; Hardt, Stefan

    2014-01-01

    Objective: To evaluate the safety and feasibility of percutaneous left atrial appendage occlusion (LAAO) in patients with atrial fibrillation (AF) and previous intracranial hemorrhage (ICH). Methods: In an explorative, prospective, single-center, observational study, LAAO was performed in patients with previous ICH and AF using the Amplatzer Cardiac Plug device. Risks of ischemic strokes and hemorrhagic complications were estimated using the CHA2DS2Vasc score and the HAS-BLED score. Before and 1, 6, 12, and 24 months after the procedure, clinical status and complications were recorded. Major complications were predefined as periprocedural stroke, death, pericardial effusion, and device embolism. Results: LAAO was performed in 20 patients. Based on CHA2DS2Vasc score (mean 4.5 ± 1.4) and HAS-BLED score (mean 4.7 ± 1.0), annual risks of stroke and hemorrhagic complications were 4.0%–6.7% and 8.7%–12.5%, respectively. No patient had a procedure-related complication. Minor postprocedural complications were observed in 4/20 patients (2 inguinal hematoma, 1 self-limiting asystole, and 1 thrombus formation on device). No ischemic or hemorrhagic stroke occurred during a mean follow-up of 13.6 ± 8.2 months. Conclusions: In this first study of LAAO in patients with previous ICH, LAAO appears feasible and safe. A larger, controlled trial is needed to assess the efficacy and safety of the procedure compared to other preventive measures. Classification of evidence: This study provides Class III evidence that in patients with a history of previous ICH and AF, percutaneous LAAO is safe and feasible. PMID:24319042

  7. Robotic-assisted left atrial ligation for stroke reduction in chronic atrial fibrillation: a case report.

    PubMed

    Kiaii, Bob; McClure, R Scott; Skanes, Alan C; Ross, Ian G; Spouge, Alison R; Swinamer, Stuart; Rayman, Reiza; Bainbridge, Daniel T; Iglesias, Ivan; Novick, Richard J

    2006-01-01

    Patients with atrial fibrillation are at significant risk for sustaining a thromboembolic stroke. More than 90% of thromboemboli form in the left atrial appendage. Ligation of the left atrial appendage to reduce the risk of stroke is often performed in connection with other cardiac surgical procedures. As a stand-alone procedure, however, left atrial ligation has generally been deemed too invasive and has gained little support as an alternative therapeutic option. We report a case of port-access robotic-assisted left atrial ligation as a stand-alone procedure in a patient with chronic atrial fibrillation in whom anticoagulation was a contraindication. To our knowledge, this is the first reported case of stand-alone robotic-assisted left atrial ligation in the literature. PMID:16387671

  8. Idiopathic atrial fibrillation in a champion Standardbred racehorse.

    PubMed

    Stewart, G A; Fulton, L J; McKellar, C D

    1990-05-01

    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. PMID:2378602

  9. Atrial Fibrillation, Neurocognitive Decline and Gene Expression After Cardiopulmonary Bypass

    PubMed Central

    Dalal, Rahul S.; Sabe, Ashraf A.; Elmadhun, Nassrene Y.; Ramlawi, Basel; Sellke, Frank W.

    2015-01-01

    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

  10. Surgical Ablation of Atrial Fibrillation during Mitral-Valve Surgery

    PubMed Central

    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

    2015-01-01

    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

  11. Dronedarone: an emerging therapy for atrial fibrillation.

    PubMed

    Rosei, Enrico Agabiti; Salvetti, Massimo

    2010-06-01

    Atrial fibrillation (AF) is a common arrhythmia, with a prevalence ranging from 0.1% to 9.0% at different ages, and is associated with increased cardiovascular events and mortality. A significant increase in the prevalence of the disease is expected to occur in the coming years as a consequence of the aging of the population and advances in the management of coronary artery disease and heart failure. Effective rhythm control may be difficult to obtain in a significant proportion of patients with AF. The limited efficacy and the possible adverse effects of antiarrhythmic drugs has led researchers to focus their attention on new molecules, in a search of compounds with antiarrhythmic efficacy and a more favourable safety profile. Among several new drugs developed for the management of AF, dronedarone, a benzofuran derivative that shares many of the antiarrhythmic properties of amiodarone, but with a more favourable safety profile, seems particularly promising. The drug is noniodinated, has less lipophilicity, reaches therapeutic concentrations over a shorter period of time and has lower tissue accumulation. Dronedarone, similarly to amiodarone, exhibits electrophysiologic characteristics of all 4 Vaughan Williams classes. Clinical studies have shown that dronedarone effectively reduces ventricular rate, may prevent or delay the recurrence of AF, and may reduce cardiovascular morbidity and mortality in patients with AF or atrial flutter. The drug has an overall good safety profile, in particular with low pulmonary and thyroid toxicity. An important exception is represented by patients with unstable haemodynamic conditions, in which the use of dronedarone has been found to be associated with an increase in mortality. Dronedarone has been recently approved for clinical use by the Food and Drug Administration and by the European Medicines Agency. Further results from trials and clinical use will better define the efficacy and safety profile of dronedarone in AF compared

  12. Anti-thromboembolic strategies in atrial fibrillation.

    PubMed

    Cocco, Giuseppe; Amiet, Philpp; Jerie, Paul

    2016-01-01

    Oral anticoagulation (OAC) is highly effective for stroke prevention in high-risk-patients with atrial fibrillation (AF). AF is also a risk for dementia, and effective OAC reduces the risk of dementia. Up to 30% of patients with AF have a coronary artery disease and antiplatelets are used to avoid thrombotic complications. Patients with AF often have an acute coronary syndrome (ACS) and undergo a percutaneous intervention with stent-implantation. These patients require a triple therapy, i.e. the combination of OAC with dual-antiplatelet therapy. It is obvious that OAC may induce bleeding with potentially deleterious effects on mortality. Even the occurrence of minor bleeding is problematic. The review describes available data on used anti-thromboembolic regimens in patients treated with OAC (vitamin K antagonists and non-vitamin K antagonists) who need a triple therapy (i.e. anticoagulation and antiplatelets). Most data are from patients who were treated for an ACS and cannot be directly extrapolated for patients with AF. The impact of used stents and novel P2Y12 antagonist-antiplatelets and duration of triple therapy is discussed. Often some high-risk patients with AF would need anticoagulation but cannot be given this therapy be-cause of excessive bleeding risks or contraindicating comorbidities: in these patients left atrial appendage closure with an occluding device can be used as an alternative to anti-thromboem-bolic therapy. The unavoidable anti-thromboembolic triple therapy carries a strong potential for bleeding events, which increase mortality. We have many data and several recommendations are offered. Nonetheless, we lack solid data on the best anti-thromboembolic regimen in patients with AF who need anticoagulation and antiplatelets. PMID:26779967

  13. [Atrial fibrillation and regular tachycardia in two young patients--are both treated with atrial fibrillation ablation?].

    PubMed

    von Bodman, G; Brömsen, J; Kopf, C; Füller, M; Block, M

    2014-04-17

    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.

  14. Predictors of atrial fibrillation termination and clinical success of catheter ablation of persistent atrial fibrillation.

    PubMed

    Heist, E Kevin; Chalhoub, Fadi; Barrett, Conor; Danik, Stephan; Ruskin, Jeremy N; Mansour, Moussa

    2012-08-15

    The termination of persistent atrial fibrillation (AF) during catheter ablation has been associated in some, but not all, studies with reduced arrhythmia during clinical follow-up. We sought to determine the rate of persistent AF termination achievable with a stepwise ablation strategy, the predictors of AF termination, and the clinical outcomes associated with termination and nontermination. A total of 143 consecutive patients (age 62 ± 9 years, AF duration 5.7 ± 5.2 years) with persistent and longstanding persistent AF resistant to antiarrhythmic medication who presented in AF for catheter ablation were studied. Ablation was done with a stepwise approach, including pulmonary vein isolation, followed by complex fractionated atrial electrogram ablation and ablation of resultant atrial tachycardias. Clinical follow-up was then performed after a 2-month blanking period to assess arrhythmia recurrence, defined as AF or atrial tachycardia lasting ≥ 30 seconds. AF termination by ablation was achieved in 95 (66%) of the 143 patients. Multivariate predictors of AF termination included longer baseline AF cycle length (p <0.001) and smaller left atrial size (p = 0.002). AF termination by ablation was associated with both a lower incidence of arrhythmia recurrence after a single procedure without antiarrhythmic drugs (p = 0.01) and overall clinical success (single or multiple procedures, with or without antiarrhythmic drugs; p = 0.005). On multivariate analysis, the predictors of overall clinical success included AF termination by ablation (p = 0.001), a shorter ablation duration (p = 0.002), younger age (p = 0.02), male gender (p = 0.03), and the presence of hypertension (p = 0.03). In conclusion, among patients with persistent AF, termination of AF by ablation can be achieved in most patients and is associated with reduced recurrence of arrhythmia. PMID:22591670

  15. The role of obesity in atrial fibrillation.

    PubMed

    Nalliah, Chrishan Joseph; Sanders, Prashanthan; Kottkamp, Hans; Kalman, Jonathan M

    2016-05-21

    Atrial fibrillation (AF) is commonly associated with overweight and obesity. Both conditions have been identified as major global epidemics associated with increased mortality and morbidity. Overweight populations have higher incidence, prevalence, severity, and progression of AF compared with their normal weight counterparts. Additionally, weight change appears to accompany alteration of arrhythmia profile, raising overweight, and obesity as potential targets for intervention. Recent clinical data confirm hypothesis drawn from epidemiological studies that durable weight reduction strategies facilitate effective management of AF. Stable weight loss decreases AF burden and AF recurrence following treatment. Structural remodelling in response to weight loss suggests that reverse remodelling of the AF substrate mediates improvement of arrhythmia profile. Obesity often co-exists with multiple AF risk factors that improve in response to weight loss, making a consolidated approach of weight loss and AF risk factor management preferable. However, weight loss for AF remains in its infancy, and its broad adoption as a management strategy for AF remains to be defined.

  16. Update on the management of atrial fibrillation.

    PubMed

    Amerena, John V; Walters, Tomos E; Mirzaee, Sam; Kalman, Jonathan M

    2013-11-01

    Atrial fibrillation (AF) is a common arrhythmia, with a prevalence that increases markedly with increasing age. Presence of AF has implications for management of future stroke risk. If the patient's pulse is irregular, an electrocardiogram should be ordered. Key management decisions are whether to adopt a rhythm control or a rate control strategy and whether to initiate anticoagulation. The primary aim of a rhythm control strategy is improved symptom control. AF ablation may be considered in younger patients (aged < 65 years) with paroxysmal or early persistent AF. AF increases the risk of stroke, and anticoagulation should be considered on the basis of stroke risk - clearly indicated with a CHADS 2 score (congestive heart failure, hypertension, age ≥ 75 years, diabetes, 1 point each; previous stroke or transient ischaemic attack, 2 points) of ≥ 2 - independent of the type of AF. In most patients with AF, the benefit of stroke reduction with systemic anticoagulation will outweigh its bleeding risks. All anticoagulants and antiplatelet agents increase the risk of bleeding. However, the new oral anticoagulants tend to have an improved safety profile, particularly in regard to intracranial bleeding, and are at least as effective as warfarin for stroke prevention.

  17. Pharmacotherapy in Medicare Beneficiaries With Atrial Fibrillation

    PubMed Central

    Piccini, Jonathan P.; Mi, Xiaojuan; DeWald, Tracy A.; Go, Alan S.; Hernandez, Adrian F.; Curtis, Lesley H.

    2013-01-01

    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

  18. Lone atrial fibrillation: does it exist?

    PubMed

    Wyse, D George; Van Gelder, Isabelle C; Ellinor, Patrick T; Go, Alan S; Kalman, Jonathan M; Narayan, Sanjiv M; Nattel, Stanley; Schotten, Ulrich; Rienstra, Michiel

    2014-05-01

    The historical origin of the term "lone atrial fibrillation" (AF) predates by 60 years our current understanding of the pathophysiology of AF, the multitude of known etiologies for AF, and our ability to image and diagnose heart disease. The term was meant to indicate AF in patients for whom subsequent investigations could not demonstrate heart disease, but for many practitioners has become synonymous with "idiopathic AF." As the list of heart diseases has expanded and diagnostic techniques have improved, the prevalence of lone AF has fallen. The legacy of the intervening years is that definitions of lone AF in the literature are inconsistent so that studies of lone AF are not comparable. Guidelines provide a vague definition of lone AF but do not provide direction about how much or what kind of imaging and other testing are necessary to exclude heart disease. There has been an explosion in the understanding of the pathophysiology of AF in the last 20 years in particular. Nevertheless, there are no apparently unique mechanisms for AF in patients categorized as having lone AF. In addition, the term "lone AF" is not invariably useful in making treatment decisions, and other tools for doing so have been more thoroughly and carefully validated. It is, therefore, recommended that use of the term "lone AF" be avoided. PMID:24530673

  19. Atrial fibrillation: review of current treatment strategies

    PubMed Central

    Xu, Joshua; Luc, Jessica G. Y.

    2016-01-01

    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

  20. [New oral anticoagulants in atrial fibrillation].

    PubMed

    Veltkamp, R; Hacke, W

    2011-02-01

    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. PMID:21286676

  1. New Oral Anticoagulants for Atrial Fibrillation

    PubMed Central

    Shafeeq, Hira; Tran, Tran H.

    2014-01-01

    Atrial fibrillation (AF) is the most common cardiac arrhythmia in the U.S. Anticoagulation is recommended for stroke prevention in AF patients with intermediate-to-high stroke risk (i.e., patients with a CHADS2 score of 1 or greater). Warfarin was previously the only option for oral anticoagulation in these patients, but three new oral anticoagulants have become available as alternatives for warfarin in patients with nonvalvular AF. The advantages of the newer agents include a rapid onset, predictable pharmacokinetics, and no need for routine anticoagulation monitoring. Dabigatran (Pradaxa) and apixaban (Eliquis) have demonstrated improved efficacy compared with warfarin. Rivaroxaban (Xarelto) was non-inferior to warfarin for stroke prevention in AF. Apixaban demonstrated a reduced incidence of major bleeding compared with warfarin and a reduction in all-cause mortality. Limitations to the use of the new oral anticoagulants include the lack of a reversal agent; an inability to use the therapies in specific patient populations (such as those with severe renal or hepatic impairment); limited experience with drug–drug and drug–disease interactions; and a lack of available coagulation tests to quantify their effects. Although the newer agents have higher acquisition costs, the benefits of cost savings may be derived from the potential for decreasing the incidence of hemorrhagic stroke and intracranial bleeding and reducing the need for anticoagulation monitoring. Benefits and risks should be carefully weighed before these agents are prescribed for patients presenting with new-onset AF. PMID:24672216

  2. Dedifferentiation of atrial cardiomyocytes as a result of chronic atrial fibrillation.

    PubMed Central

    Ausma, J.; Wijffels, M.; van Eys, G.; Koide, M.; Ramaekers, F.; Allessie, M.; Borgers, M.

    1997-01-01

    Chronic atrial fibrillation was induced in goats by electrical pacing. After 9 to 23 weeks of sustained atrial fibrillation, the morphology of the atrial structures was examined. The majority of the cardiomyocytes exhibited marked changes in their cellular substructures, with the replacement of sarcomeres by glycogen as the main characteristic. Using immuno-histochemical staining procedures, we assessed the expression and organization of contractile and cytoskeletal proteins in these cases and compared them with the expression and organization of these proteins in normal atria. Part of the atrial cardiomyocytes acquired a dedifferentiated phenotype, as deduced from the re-expression of alpha-smooth muscle actin, the disappearance of cardiotin, and the staining patterns of titin, which resembled those of embryonic cardiomyocytes. From these results we conclude that chronic atrial fibrillation induces myocardial dedifferentiation. This model of chronic atrial fibrillation in goats offers the possibility to study the time course of changes in cardiac structure during sustained atrial fibrillation and after cardioversion. Images Figure 1 Figure 2 Figure 3 Figure 5 Figure 6 Figure 7 PMID:9327732

  3. Genetic Mutations in African Patients with Atrial Fibrillation: Rationale and Design of the Study of Genetics of Atrial Fibrillation in an African Population (SIGNAL)

    PubMed Central

    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.

    2015-01-01

    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

  4. Determinants of Left Atrial Volume in Patients with Atrial Fibrillation

    PubMed Central

    Hochgruber, Thomas; Krisai, Philipp; Zimmermann, Andreas J.; Aeschbacher, Stefanie; Pumpol, Katrin; Kessel-Schaefer, Arnheid; Stephan, Frank-Peter; Handschin, Nadja; Sticherling, Christian; Osswald, Stefan; Kaufmann, Beat A.; Paré, Guillaume; Kühne, Michael; Conen, David

    2016-01-01

    Introduction Left atrial (LA) enlargement is an important risk factor for incident stroke and a key determinant for the success of rhythm control strategies in patients with atrial fibrillation (AF). However, factors associated with LA volume in AF patients remain poorly understood. Methods Patients with paroxysmal or persistent AF were enrolled in this study. Real time 3-D echocardiography was performed in all participants and analyzed offline in a standardized manner. We performed stepwise backward linear regression analyses using a broad set of clinical parameters to determine independent correlates for 3-D LA volume. Results We included 210 patients (70.9% male, mean age 61±11years). Paroxysmal and persistent AF were present in 95 (45%) and 115 (55%) patients, respectively. Overall, 115 (55%) had hypertension, 11 (5%) had diabetes, and 18 (9%) had ischemic heart disease. Mean indexed LA volume was 36±12ml/m2. In multivariable models, significant associations were found for female sex (β coefficient -10.51 (95% confidence interval (CI) -17.85;-3.16), p = 0.0053), undergoing cardioversion (β 11.95 (CI 5.15; 18.74), p = 0.0006), diabetes (β 14.23 (CI 2.36; 26.10), p = 0.019), body surface area (BSA) (β 34.21 (CI 19.30; 49.12), p<0.0001), glomerular filtration rate (β -0.21 (CI -0.36; -0.06), p = 0.0064) and plasma levels of NT-pro brain natriuretic peptide (NT-proBNP) (β 6.79 (CI 4.05; 9.52), p<0.0001), but not age (p = 0.59) or hypertension (p = 0.42). Our final model explained 52% of the LA volume variability. Conclusions In patients with AF, the most important correlates with LA volume are sex, BSA, diabetes, renal function and NT-proBNP, but not age or hypertension. These results may help to refine rhythm control strategies in AF patients. PMID:27701468

  5. Atrial Ectopy as a Predictor of Incident Atrial Fibrillation

    PubMed Central

    Dewland, Thomas A.; Vittinghoff, Eric; Mandyam, Mala C.; Heckbert, Susan R.; Siscovick, David S.; Stein, Phyllis K.; Psaty, Bruce M.; Sotoodehnia, Nona; Gottdiener, John S.; Marcus, Gregory M.

    2014-01-01

    Background Atrial fibrillation (AF) prediction models have unclear clinical utility given the absence of AF prevention therapies and the immutability of many risk factors. Premature atrial contractions (PACs) play a critical role in AF pathogenesis and may be modifiable. Objective To investigate whether PAC count improves model performance for AF risk. Design Prospective cohort study. Setting 4 U.S. communities. Patients A random subset of 1260 adults without prevalent AF enrolled in the Cardiovascular Health Study between 1989 and 1990. Measurements The PAC count was quantified by 24-hour electrocardiography. Participants were followed for the diagnosis of incident AF or death. The Framingham AF risk algorithm was used as the comparator prediction model. Results In adjusted analyses, doubling the hourly PAC count was associated with a significant increase in AF risk (hazard ratio, 1.17 [95% CI, 1.13 to 1.22]; P < 0.001) and overall mortality (hazard ratio, 1.06 [CI, 1.03 to 1.09]; P < 0.001). Compared with the Framingham model, PAC count alone resulted in similar AF risk discrimination at 5 and 10 years of follow-up and superior risk discrimination at 15 years. The addition of PAC count to the Framingham model resulted in significant 10-year AF risk discrimination improvement (c-statistic, 0.65 vs. 0.72; P < 0.001), net reclassification improvement (23.2% [CI, 12.8% to 33.6%]; P < 0.001), and integrated discrimination improvement (5.6% [CI, 4.2% to 7.0%]; P < 0.001). The specificity for predicting AF at 15 years exceeded 90% for PAC counts more than 32 beats/h. Limitation This study does not establish a causal link between PACs and AF. Conclusion The addition of PAC count to a validated AF risk algorithm provides superior AF risk discrimination and significantly improves risk reclassification. Further study is needed to determine whether PAC modification can prospectively reduce AF risk. Primary Funding Source American Heart Association, Joseph Drown Foundation

  6. Atrial fibrillation and pneumothorax after transthoracic needle lung biopsy

    PubMed Central

    Liu, Alexander; Southern, Iain; Nicol, Edward

    2012-01-01

    An obese 65-year-old male smoker with chronic obstructive pulmonary disease developed an iatrogenic pneumothorax with pulmonary haemorrhage during an elective transthoracic needle biopsy of a pulmonary lesion. Successful re-inflation was achieved with a chest drain which was then removed before transfer to the medical ward. He later developed persistent atrial fibrillation with breathlessness and haemoptysis. He was treated empirically for a pulmonary embolus, which was subsequently ruled out with CT pulmonary angiogram. Serial chest radiographs demonstrated recurrence of his pneumothorax and a chest drain was re-inserted. His atrial fibrillation was erroneously managed as supraventricular tachycardia, which was resistant to vagal manoeuvres and adenosine but later responded to intravenous amiodarone before a further relapse. Upon successful management of the pneumothorax, his atrial fibrillation terminated. This case highlighted the persistent and serious nature of complications posttransthoracic needle biopsy. PMID:22665868

  7. Novel Anticoagulants in Atrial Fibrillation: Monitoring, Reversal and Perioperative Management

    PubMed Central

    Shamoun, Fadi; Obeid, Hiba; Ramakrishna, Harish

    2015-01-01

    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

  8. Warfarin therapy for an octogenarian who has atrial fibrillation.

    PubMed

    Gage, B F; Fihn, S D; White, R H

    2001-03-20

    In North America, atrial fibrillation is associated with at least 75 000 ischemic strokes each year. Most of these strokes occur in patients older than 75 years of age. The high incidence of stroke in very elderly persons reflects the increasing prevalence of atrial fibrillation that occurs with advanced age, the high incidence of stroke in elderly patients, and the failure of physicians to prescribe antithrombotic therapy in most of these patients. This failure is related to the increased risk for major hemorrhage with advanced age, obfuscating the decision to institute stroke prophylaxis with antithrombotic therapy. This case-based review describes the risk and benefits of prescribing antithrombotic therapy for a hypothetical 80-year-old man who has atrial fibrillation and hypertension, and it offers practical advice on managing warfarin therapy. After concluding that the benefits of warfarin outweigh its risks in this patient, we describe how to initiate warfarin therapy cautiously and how to monitor and dose the drug. We then review five recent randomized, controlled trials that document the increased risk for stroke when an international normalized ratio (INR) of less than 2.0 is targeted among patients with atrial fibrillation. Next, we make the case that cardioversion is not needed for this asymptomatic patient with chronic atrial fibrillation. Instead, we choose to leave the patient in atrial fibrillation and to control his ventricular rate with atenolol. Later, when the INR increases to 4.9, we advocate withholding one dose of warfarin and repeating the INR test. Finally, when the patient develops dental pain, we review the analgesic agents that are safe to take with warfarin and explain why warfarin therapy does not have to be interrupted during a subsequent dental extraction. PMID:11255522

  9. [More with atrial fibrillation, anticoagulants since the coming of NOAK ].

    PubMed

    Forslund, Tomas; von Euler, Mia; Johnsson, Hans; Holmström, Margareta; Wettermark, Björn; Hjemdahl, Paul

    2015-01-01

    Since the introduction of NOAC (non-vitamin K antagonist oral anticoagulants) in 2011 as thromboprophylactic treatment for patients with atrial fibrillation, AF, the number of patients with a diagnosis of atrial fibrillation has increased markedly in our health care registers. The proportion of patients treated with warfarin or NOAC has increased from 47 % to 58 % in 2013. The use of acetylsalicylic acid in patients is decreasing rapidly in patients with AF. NOAC are mostly prescribed by specialists and are mainly used in younger patients with lower CHA2DS2-VASc scores and lower risk for renal insufficiency and bleeding. PMID:25584610

  10. Atrial fibrillation and sleep-disordered breathing

    PubMed Central

    Lavergne, Florent; Morin, Laurent; Armitstead, Jeff; Benjafield, Adam; Richards, Glenn

    2015-01-01

    Atrial fibrillation (AF) is a common supraventricular arrhythmia that increases in prevalence with increasing age and in the presence of comorbidities such as heart failure (HF). AF increases the risk of a number of serious complications, including stroke and HF. As a result, the rate of hospitalization is high, making AF a costly disease. Treatment strategies for AF are broadly based around rate and rhythm control, either pharmacological or mechanical. There appear to be a number of links between sleep-disordered breathing (SDB) and AF, although further studies are needed to fully understand the physiological mechanisms that link these conditions. Patients with AF and SDB share a number of risk factors and comorbidities, including age, male sex, hypertension, congestive HF and coronary artery disease (CAD), and the prevalence of SDB in AF is higher than in the general population. Prevalence rates of obstructive sleep apnea (OSA) in patients with AF have been reported to range from 21% to just over 80%. The prevalence of central sleep apnea (CSA) in patients with AF is less well defined, but appears to be particularly high in patients who also have HF and a reduced left ventricular ejection fraction (LVEF). The frequency of apneas can be reduced by effective treatment of AF, while co-existing OSA reduces the effectiveness of treatments for AF and there is an increased risk of arrhythmia recurrence in the presence of SDB. Treating OSA with continuous positive airway pressure (CPAP) therapy has shown the potential to decrease the incidence of AF, improve the effectiveness of AF interventions, and decrease the risk of arrhythmia recurrence, although data from large randomized, controlled clinical trials are lacking. Based on available data, inclusion of SDB recognition and management strategies as part of AF management appears to have the potential to reduce the impact of this arrhythmia at both the individual and societal levels, and has been recognized as important

  11. The atrial fibrillation conundrum in dialysis patients.

    PubMed

    De Vriese, An S; Caluwé, Rogier; Raggi, Paolo

    2016-04-01

    The burden of atrial fibrillation (AF) and the risk of stroke are high in dialysis patients. The decision to use anticoagulation rests heavily on effective risk stratification. Because both the pathophysiology of the disease and the response to therapy differ in dialysis, data from the general population cannot be extrapolated. The effect of vitamin K antagonists (VKAs) on the risk of stroke in dialysis patients with AF has not been studied in randomized trials. The available observational data provide contradictory results, reflecting differences in the degree of residual confounding, quality of international normalized ratio control, and stroke characterization. Dialysis patients have a high baseline bleeding risk. It remains unclear to what extent VKAs affect the overall bleeding propensity, but they may significantly increase the risk of intracerebral hemorrhage. Vascular calcifications are extremely prevalent in dialysis patients and independently associated with an adverse outcome. Vitamin K antagonists inhibit the activity of key anticalcifying proteins and may thus compound the risk of vascular calcification progression in dialysis. In the absence of evidence-based guidelines for anticoagulation in dialysis patients with AF, we provide recommendations to assist clinicians in individualized risk stratification. We further propose that new oral anticoagulants may have a better benefit-risk profile in dialysis patients than VKA, provided appropriate dose reductions are made. New oral anticoagulant may yield more on-target anticoagulation, reduce the risk of intracerebral bleeding, and not interfere with vascular calcification biology. Clinical trials with new oral anticoagulant in dialysis patients are eagerly awaited, to reveal whether these assumptions can be confirmed. PMID:26995377

  12. Whole Exome Sequencing in Atrial Fibrillation.

    PubMed

    Lubitz, Steven A; Brody, Jennifer A; Bihlmeyer, Nathan A; Roselli, Carolina; Weng, Lu-Chen; Christophersen, Ingrid E; Alonso, Alvaro; Boerwinkle, Eric; Gibbs, Richard A; Bis, Joshua C; Cupples, L Adrienne; Mohler, Peter J; Nickerson, Deborah A; Muzny, Donna; Perez, Marco V; Psaty, Bruce M; Soliman, Elsayed Z; Sotoodehnia, Nona; Lunetta, Kathryn L; Benjamin, Emelia J; Heckbert, Susan R; Arking, Dan E; Ellinor, Patrick T; Lin, Honghuang

    2016-09-01

    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

  13. Surgical options for treatment of atrial fibrillation.

    PubMed

    La Meir, Mark

    2014-01-01

    If we want to improve the outcomes, increase the success and reduce the complication rate of existing treatment strategies in concomitant and stand-alone atrial fibrillation (AF) procedures, we will have to increase our understanding of the pathophysiology, and of the disease, the limitations of current energy sources and ablation catheters, the different possible lesion sets, as well as improve communication between the electrophysiologist and cardiac surgeon. The technical limitations of percutaneous endocardial ablation procedures and the empirical techniques in surgical AF procedures necessitate new and innovative approaches. Surgeons should aim to improve the quality of the lesion set and minimize the invasiveness of existing techniques. The Maze procedure remains the basis upon which most of the more limited concomitant ablation procedures are and will be designed, but in stand-alone patients, recent progress has directed us towards either a single-step or sequential combined percutaneous endocardial procedure with a thoracoscopic epicardial procedure on the beating heart. A dedicated team of electrophysiologists and cardiothoracic surgeons can now work together to perform AF procedures. This can guide us to determine if there is an additional value of limiting the lesion set of the Maze procedure in concomitant surgery, and of an epicardial access in the treatment of stand-alone AF on the beating heart. If so, we will better understand which energy sources, lesion sets and surgical techniques are able to give us a three-dimensional knowledge and a three-dimensional treatment of AF. As a result, we can expect to obtain a higher single procedure long-term success rate with an acceptable low complication rate.

  14. Whole Exome Sequencing in Atrial Fibrillation

    PubMed Central

    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.

    2016-01-01

    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

  15. Epidemiology of atrial fibrillation in Spain in the past 20 years.

    PubMed

    Pérez-Villacastín, Julián; Pérez Castellano, Nicasio; Moreno Planas, Javier

    2013-07-01

    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.

  16. Inflammation and C-reactive protein in atrial fibrillation: cause or effect?

    PubMed

    Galea, Roberto; Cardillo, Maria Teresa; Caroli, Annalisa; Marini, Maria Giulia; Sonnino, Chiara; Narducci, Maria L; Biasucci, Luigi M

    2014-10-01

    Atrial fibrillation is associated with substantial morbidity and mortality rates. The incompletely understood pathogenesis of this cardiac dysrhythmia makes it difficult to improve approaches to primary and secondary prevention. Evidence has accumulated in regard to a relationship between inflammation and atrial fibrillation. Investigators have correlated the dysrhythmia with myocarditis, pericardiotomy, and C-reactive protein levels, suggesting that inflammation causes atrial fibrillation or participates in its onset and continuation. Conversely, other investigators suggest that atrial fibrillation induces an inflammatory response. In this review, we summarize and critically discuss the nature and clinical role of inflammation and C-reactive protein in atrial fibrillation. PMID:25425976

  17. Evaluating the Atrial Myopathy Underlying Atrial Fibrillation: Identifying the Arrhythmogenic and Thrombogenic Substrate.

    PubMed

    Goldberger, Jeffrey J; Arora, Rishi; Green, David; Greenland, Philip; Lee, Daniel C; Lloyd-Jones, Donald M; Markl, Michael; Ng, Jason; Shah, Sanjiv J

    2015-07-28

    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 the 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 before the onset of AF, there is no current evaluation to identify the preclinical atrial myopathy. Atrial fibrosis is 1 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 the 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. Although 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.

  18. Evaluating the Atrial Myopathy Underlying Atrial Fibrillation: Identifying the Arrhythmogenic and Thrombogenic Substrate.

    PubMed

    Goldberger, Jeffrey J; Arora, Rishi; Green, David; Greenland, Philip; Lee, Daniel C; Lloyd-Jones, Donald M; Markl, Michael; Ng, Jason; Shah, Sanjiv J

    2015-07-28

    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 the 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 before the onset of AF, there is no current evaluation to identify the preclinical atrial myopathy. Atrial fibrosis is 1 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 the 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. Although 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

  19. Evaluating the Atrial Myopathy Underlying Atrial Fibrillation: Identifying the Arrhythmogenic and Thrombogenic Substrate

    PubMed Central

    Goldberger, Jeffrey J.; Arora, Rishi; Green, David; Greenland, Philip; Lee, Daniel C.; Lloyd-Jones, Donald M.; Markl, Michael; Ng, Jason; Shah, Sanjiv J.

    2015-01-01

    Atrial disease or myopathy forms the substrate for atrial fibrillation (AF) and underlies the potential for atrial thrombus formation and subsequent stroke. Current diagnostic approaches in patients with AF focus on identifying clinical predictors with evaluation of left atrial size by echocardiography serving as the sole measure specifically evaluating the atrium. Although the atrial substrate underlying AF is likely developing for years prior to the onset of AF, there is no current evaluation to identify the pre-clinical atrial myopathy. Atrial fibrosis is one component of the atrial substrate that has garnered recent attention based on newer MRI techniques that have been applied to visualize atrial fibrosis in humans with prognostic implications regarding success of treatment. Advanced ECG signal processing, echocardiographic techniques, and MRI imaging of fibrosis and flow provide up-to-date approaches to evaluate the atrial myopathy underlying AF. While thromboembolic risk is currently defined by clinical scores, their predictive value is mediocre. Evaluation of stasis via imaging and biomarkers associated with thrombogenesis may provide enhanced approaches to assess risk for stroke in patients with AF. Better delineation of the atrial myopathy that serves as the substrate for AF and thromboembolic complications might improve treatment outcomes. Furthermore, better delineation of the pathophysiologic mechanisms underlying the development of the atrial substrate for AF, particularly in its earlier stages, could help identify blood and imaging biomarkers that could be useful to assess risk for developing new onset AF and suggest specific pathways that could be targeted for prevention. PMID:26216085

  20. Functional Role and Mechanism of microRNA-28b in Atrial Myocyte in a Persistent Atrial Fibrillation Rat Model

    PubMed Central

    Wang, Yongbin; Kang, Weiqiang; Wang, Xu; Chen, Meina; Qin, Qiaoji; Guo, Minglei; Ge, Zhiming

    2016-01-01

    Background Persistent atrial fibrillation has been indicated to be related with microRNA-28b. However, the exact role of microRNA-28b in persistent atrial fibrillation needs to be further elucidated. Therefore, this study aimed to establish a rat model of persistent atrial fibrillation to investigate the level of microRNA-28b in atrial myocytes and to explore the molecular mechanism involved. Material/Methods A persistent atrial fibrillation model was established in rats by using chronic rapid atrial pacing induction. The size of the heart was measured by ultrasonic method. The expression of microRNA-28b in left atrial myocytes was quantified by RT-PCR. Cardiomyocytes were isolated and cultured to detect cell proliferation and apoptosis by MTT and flow cytometry, respectively. The specific inhibitor of ERK signaling pathway, PD98059, was used to further illustrate the role of ERK signaling pathway in the modulation of cardiomyocytes in persistent atrial fibrillation. Results MicroRNA-28b was up-regulated in the experimental rat model with persistent atrial fibrillation. The proliferation of cardiomyocytes was significantly inhibited with potentiated apoptosis. Blockage of the ERK pathway suppressed the microRNA-28b expression and inhibited cell apoptosis. Conclusions microRNA-28b-induced growth inhibition and cell apoptosis of atrial myocytes was observed in the rat model with persistent atrial fibrillation, via activation of the ERK signaling pathway. PMID:27574952

  1. MRI Screening for Chronic Anticoagulation in Atrial Fibrillation

    PubMed Central

    Fisher, Mark

    2013-01-01

    Anticoagulation is highly effective in preventing stroke due to atrial fibrillation, but numerous studies have demonstrated low utilization of anticoagulation for these patients. Assessment of clinicians’ attitudes on this topic indicate that fear of intracerebral hemorrhage (ICH), rather than appreciation of anticoagulation benefits, largely drives clinical decision-making for treatment with anticoagulation in atrial fibrillation. Risk stratification strategies have been used for anticoagulation benefits and hemorrhage risk, but ICH is not specifically addressed in the commonly used hemorrhage risk stratification systems. Cerebral microbleeds are cerebral microscopic hemorrhages demonstrable by brain MRI, indicative of prior microhemorrhages, and predictive of future risk of ICH. Prevalence of cerebral microbleeds increases with age; and cross-sectional and limited prospective studies generally indicate that microbleeds confer substantial risk of ICH in patients treated with chronic anticoagulation. MRI thus is a readily available and appealing modality that can directly assess risk of future ICH in patients receiving anticoagulants for atrial fibrillation. Incorporation of MRI into routine practice is, however, fraught with difficulties, including the uncertain relationship between number and location of microbleeds and ICH risk, as well as cost-effectiveness of MRI. A proposed algorithm is provided, and relevant advantages and disadvantages are discussed. At present, MRI screening appears most appropriate for a subset of atrial fibrillation patients, such as those with intermediate stroke risk, and may provide reassurance for clinicians whose concerns for ICH tend to outweigh benefits of anticoagulation. PMID:24109470

  2. [Torsade de pointes in the management of atrial fibrillation].

    PubMed

    Urtubia Palacios, A; Usieto López, L; Fernández Esteban, M I; Puértolas Ortega, M

    2014-01-01

    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.

  3. Atrial Fibrillation Complications | NIH MedlinePlus the Magazine

    MedlinePlus

    ... research has led to many advances in medical knowledge and care. However, many questions remain about various diseases and conditions, including atrial fibrillation. The NHLBI continues to support research aimed at learning more about AFib. For example, NHLBI-supported research ...

  4. Surgical Ablation of Atrial Fibrillation Using Energy Sources.

    PubMed

    Brick, Alexandre Visconti; Braile, Domingo Marcolino

    2015-01-01

    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.

  5. New oral anticoagulants for patients with nonvalvular atrial fibrillation.

    PubMed

    Holden, Amber; Azimi, Nassir; Forest, Christopher P

    2015-11-01

    Four new oral anticoagulants have been approved for reducing stroke risk in patients with nonvalvular atrial fibrillation. Compared with warfarin, these agents offer a more predictable dose response with fewer food and drug interactions and no regular blood monitoring, although some of the drugs have an increased risk of major gastrointestinal bleeding. This article reviews the new drugs.

  6. Surgical Ablation of Atrial Fibrillation Using Energy Sources

    PubMed Central

    Brick, Alexandre Visconti; Braile, Domingo Marcolino

    2015-01-01

    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

  7. Stroke risk assessment in atrial fibrillation: risk factors and markers of atrial myopathy.

    PubMed

    Calenda, Brandon W; Fuster, Valentin; Halperin, Jonathan L; Granger, Christopher B

    2016-09-01

    Atrial fibrillation (AF) is a complex phenomenon associated with electrical, mechanical, and structural abnormalities of the atria. Ischaemic stroke in AF is only partially understood, but the mechanisms are known to be related to the atrial substrate as well as the atrial rhythm. The temporal dissociation between timing of AF and occurrence of stroke has led to the hypothesis that fibrotic, prothrombotic atrial tissue is an important cause of thrombus formation in patients with AF, independent of the atrial rhythm. Current stroke risk scores are practical, but limited in their capacity to predict stroke risk accurately in individual patients. Stroke prediction might be improved by the addition of emerging risk factors, many of which are expressions of atrial fibrosis. The use of novel parameters, including clinical criteria, biomarkers, and imaging data, might improve stroke risk prediction and inform on optimal treatment for patients with AF and perhaps individuals only at risk of AF. PMID:27383079

  8. Adjusted Left Atrial Emptying Fraction as a Predictor of Procedural Outcome after Catheter Ablation for Atrial Fibrillation

    PubMed Central

    Im, Sung Il; Kim, Sun Won; Choi, Cheol Ung; Kim, Jin Won; Yong, Hwan Seok; Kim, Eung Ju; Rha, Seung-Woon; Park, Chang Gyu; Seo, Hong Seog; Oh, Dong Joo; Lim, Hong Euy

    2015-01-01

    Structural remodeling of the left atrium is a risk factor for recurrent arrhythmia after catheter ablation for atrial fibrillation; however, data are sparse regarding the role of functional left atrial remodeling in predicting procedural outcomes. We evaluated whether left atrial transport function could be used to predict recurrent atrial fibrillation. From July 2008 through August 2010, we enrolled 202 consecutive patients who underwent catheter ablation for atrial fibrillation (paroxysmal=120, persistent=82). Left atrial volumes (LAVs) were measured by means of multislice computed tomography at every 10% of the R-R interval, and measurements were adjusted for body surface area to yield the LAV index (LAVI) at baseline. The left atrial emptying fraction (LAEF) was calculated according to LAV differences. During the mean follow-up period of 10 ± 4 months after a single ablation procedure, atrial fibrillation recurred in 59 patients (paroxysmal=19, persistent=40). Multivariate analysis revealed that persistent atrial fibrillation, early mitral inflow velocity, LAVImax, LAVImin, LAEF, LAVImax/LAEF, and LAVImin/LAEF were all independent predictors of atrial fibrillation, but the best predictor was LAVImin/LAEF (β=1.329, P=0.001). The cutoff value was 1.61 (mL/m2)/%, and the sensitivity and specificity were 74.6% and 62.2%, respectively (area under the curve=0.761). Our study shows that adjusted left atrial emptying fraction with use of multislice computed tomography might be a useful, noninvasive method to select patients for ablation. PMID:26175632

  9. Left atrial appendage closure for thromboembolism prevention in patients with atrial fibrillation: advances and perspectives

    PubMed Central

    Kong, Bin; Liu, Yu; Huang, He; Jiang, Hong

    2015-01-01

    Atrial fibrillation (AF) is a frequent cause of stroke. More than 90% of thrombi were found in the left atrial appendage (LAA) in non-valvular AF. Transcatheter LAA closure has been developed as a novel approach to reduce the risk of stroke in patients with AF over the last decade. In this article, we review the recent advances and propose the possible challenges regarding the LAA closure for thromboembolism prevention in patients with AF. PMID:25713737

  10. Percutaneous Left Atrial Appendage Ligation for Stroke Prevention in Atrial Fibrillation.

    PubMed

    Valderrábano, Miguel; Price, Matthew J

    2015-01-01

    Prevention of thromboembolic complications in atrial fibrillation remains a tremendous clinical challenge. Knowledge that the left atrial appendage (LAA) is the most common anatomical origin of cardioembolic strokes1 has been the main motivation to develop clinical and procedural strategies to exclude the LAA from the circulation, either surgically or percutaneously. This review discusses the rationale behind these strategies, their relative merits, and future prospects for LAA exclusion strategies. PMID:26306126

  11. Effect of Substrate Modification in Catheter Ablation of Paroxysmal Atrial Fibrillation

    PubMed Central

    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

    2012-01-01

    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

  12. Discrimination of Paroxysmal and Persistent Atrial Fibrillation in Patients With New-Onset Atrial Fibrillation.

    PubMed

    Igarashi, Tazuru; Niwano, Shinichi; Fukaya, Hidehira; Yoshizawa, Tomoharu; Nakamura, Hironori; Fujiishi, Tamami; Ishizue, Naruya; Oikawa, Jun; Kishihara, Jun; Murakami, Masami; Niwano, Hiroe; Ako, Junya

    2016-09-28

    Discrimination between paroxysmal and persistent atrial fibrillation (PAF and persistent AF) is important for determining the therapeutic strategy in patients with new-onset AF. We evaluated various clinical factors and P wave morphology to discriminate PAF and persistent AF patients in patients with new-onset AF.The study population consisted of 79 patients with new-onset AF (70.3 ± 10.8 years, female:male 33:46) who were retrospectively selected from 8,632 AF patients in the Kitasato University Hospital ECG storing system. PAF (n = 38) and persistent AF (n = 41) patients were diagnosed by whether the initial PAF episode continued for 1 week. The P wave morphologies were analyzed using the most recent 12 lead-ECG recording of sinus rhythm. P wave dispersion was defined as the difference between the maximum and minimum durations of all leads. Along with these data, various clinical factors were evaluated and compared between PAF and persistent AF patients.Multivariate analysis identified P wave dispersion (56.6 ± 14.8 versus 66.5 ± 12.8 msec, P = 0.002) and left atrial dimension (LAD: 40.2 ± 7.0 versus 47.7 ± 8.2 mm, P < 0.001) as independent factors for discrimination between PAF and persistent AF patients. Combining these two parameters achieved a specificity of 88.9%, a positive predictive value of 81.8%, a sensitivity of 95.3%, and a negative predictive value of 88.9%.In patients with new-onset AF, P wave dispersion and LAD were independent factors for discrimination between PAF and persistent AF.

  13. Managing atrial fibrillation in the elderly: critical appraisal of dronedarone.

    PubMed

    Trigo, Paula; Fischer, Gregory W

    2012-01-01

    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.

  14. Managing atrial fibrillation in the elderly: critical appraisal of dronedarone

    PubMed Central

    Trigo, Paula; Fischer, Gregory W

    2012-01-01

    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. PMID:22291468

  15. Role of Magnetic Resonance Imaging of Atrial Fibrosis in Atrial Fibrillation Ablation.

    PubMed

    Spragg, David D; Khurram, Irfan; Nazarian, Saman

    2013-11-01

    Atrial fibrillation (AF) likely involves a complex interplay between triggering activity, usually from pulmonary vein foci, and maintenance of the arrhythmia by an arrhythmogenic substrate. Both components of AF, triggers and substrate have been linked to atrial fibrosis and attendant changes in atrial electrophysiology. Recently, there has been a growing use of imaging modalities, particularly cardiac magnetic resonance (CMR), to quantify the burden of atrial fibrosis and scar in patients either undergoing AF ablation, or who have recently had the procedure. How to use the CMR derived data is still an open area of investigation. The aim of this article is to summarise what is known as atrial fibrosis, as assessed by traditional catheter-based techniques and newer imaging approaches, and to report on novel efforts from our group to advance the use of CMR in AF ablation patients.

  16. Nonpharmacologic approaches to the treatment of atrial fibrillation and atrial flutter.

    PubMed

    Baker, B M; Smith, J M; Cain, M E

    1995-10-01

    The high prevalence of atrial fibrillation, the associated morbidity and mortality, the absence of safe and effective drug therapy, and an increased understanding of the pathophysiologic basis of atrial fibrillation and flutter have collectively led to the development of novel nonpharmacologic treatments for the management of these arrhythmias, including the CORRIDOR and MAZE surgical procedures, catheter-based ablation and modification of AV conduction, catheter-based ablation of atrial flutter and fibrillation, and internal atrial defibrillation. These surgical and catheter-based techniques offer potentially curative therapy while sparing the long-term risk of antiarrhythmic drug therapy. For patients with typical atrial flutter, catheter ablation affords to cure rate in excess of 70%. As technological innovations further facilitate identification and ablation of the critical isthmus in the floor of the right atrium, success rates should improve substantially. For patients with atrial fibrillation, AV junction ablation with implantation of a rate-responsive ventricular pacemaker should be considered palliative therapy, as should modification of AV junction conduction. The MAZE procedure offers very high cure rates, but because it currently involves open heart surgery, patient selection is critical. Catheter-based procedures emulating aspects of the MAZE procedure may one day offer cure rates comparable to those of the surgery itself, but additional research and technological development are necessary to further define and refine the minimal effective procedure, and then to facilitate the placement of contiguous, full-thickness lesions in precise three-dimensional configurations. In the interim, the implantable automatic atrial defibrillator may offer a means for rapidly restoring sinus rhythm without the risks of long-term antiarrhythmic drug therapy.

  17. Catheter Ablation for Long-Standing Persistent Atrial Fibrillation.

    PubMed

    Romero, Jorge; Gianni, Carola; Di Biase, Luigi; Natale, Andrea

    2015-01-01

    Atrial fibrillation (AF) is the most common sustained arrhythmia worldwide and represents a major burden to health care systems. Atrial fibrillation is associated with a 4- to 5-fold increased risk of thromboembolic stroke. The pulmonary veins have been identified as major sources of atrial triggers for AF. This is particularly true in patients with paroxysmal AF but not always the case for those with long-standing persistent AF (LSPAF), in which other locations for ectopic beats have been well recognized. Structures with foci triggering AF include the coronary sinus, the left atrial appendage (LAA), the superior vena cava, the crista terminalis, and the ligament of Marshall. More than 30 studies reporting results on radiofrequency ablation of LSPAF have been published to date. Most of these are observational studies with very different methodologies using different strategies. As a result, there has been remarkable variation in short- and long-term success, which suggests that the optimal ablation technique for LSPAF is still to be elucidated. In this review we discuss the different approaches to LSPAF catheter ablation, starting with pulmonary vein isolation (PVI) through ablation lines in different left atrial locations, the role of complex fractionated atrial electrograms, focal impulses and rotor modulation, autonomic modulation (ganglionated plexi), alcohol ablation, and the future of epicardial mapping and ablation for this arrhythmia. A stepwise ablation approach requires several key ablation techniques, such as meticulous PVI, linear ablation at the roof and mitral isthmus, electrogram-targeted ablation with particular attention to triggers in the coronary sinus and LAA, and discretionary right atrial ablation (superior vena cava, intercaval, or cavotricuspid isthmus lines). PMID:26306125

  18. Catheter Ablation for Long-Standing Persistent Atrial Fibrillation

    PubMed Central

    Romero, Jorge; Gianni, Carola; Di Biase, Luigi; Natale, Andrea

    2015-01-01

    Atrial fibrillation (AF) is the most common sustained arrhythmia worldwide and represents a major burden to health care systems. Atrial fibrillation is associated with a 4- to 5-fold increased risk of thromboembolic stroke. The pulmonary veins have been identified as major sources of atrial triggers for AF. This is particularly true in patients with paroxysmal AF but not always the case for those with long-standing persistent AF (LSPAF), in which other locations for ectopic beats have been well recognized. Structures with foci triggering AF include the coronary sinus, the left atrial appendage (LAA), the superior vena cava, the crista terminalis, and the ligament of Marshall. More than 30 studies reporting results on radiofrequency ablation of LSPAF have been published to date. Most of these are observational studies with very different methodologies using different strategies. As a result, there has been remarkable variation in short- and long-term success, which suggests that the optimal ablation technique for LSPAF is still to be elucidated. In this review we discuss the different approaches to LSPAF catheter ablation, starting with pulmonary vein isolation (PVI) through ablation lines in different left atrial locations, the role of complex fractionated atrial electrograms, focal impulses and rotor modulation, autonomic modulation (ganglionated plexi), alcohol ablation, and the future of epicardial mapping and ablation for this arrhythmia. A stepwise ablation approach requires several key ablation techniques, such as meticulous PVI, linear ablation at the roof and mitral isthmus, electrogram-targeted ablation with particular attention to triggers in the coronary sinus and LAA, and discretionary right atrial ablation (superior vena cava, intercaval, or cavotricuspid isthmus lines). PMID:26306125

  19. Clinical Differences between Subtypes of Atrial Fibrillation and Flutter: Cross-Sectional Registry of 407 Patients

    PubMed Central

    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

    2015-01-01

    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

  20. ECG characterization of paroxysmal atrial fibrillation: parameter extraction and automatic diagnosis algorithm.

    PubMed

    Ros, E; Mota, S; Fernández, F J; Toro, F J; Bernier, J L

    2004-12-01

    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. PMID:15518652

  1. How and When to Screen for Atrial Fibrillation after Stroke: Insights from Insertable Cardiac Monitoring Devices

    PubMed Central

    Bridge, Francesca; Thijs, Vincent

    2016-01-01

    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

  2. Practical management of anticoagulation in patients with atrial fibrillation.

    PubMed

    Kovacs, Richard J; Flaker, Greg C; Saxonhouse, Sherry J; Doherty, John U; Birtcher, Kim K; Cuker, Adam; Davidson, Bruce L; Giugliano, Robert P; Granger, Christopher B; Jaffer, Amir K; Mehta, Bella H; Nutescu, Edith; Williams, Kim A

    2015-04-01

    Anticoagulation for atrial fibrillation has become more complex due to the introduction of new anticoagulant agents, the number and kinds of patients requiring therapy, and the interactions of those patients in the matrix of care. The management of anticoagulation has become a "team sport" involving multiple specialties in multiple sites of care. The American College of Cardiology, through the College's Anticoagulation Initiative, convened a roundtable of experts from multiple specialties to discuss topics important to the management of patients requiring anticoagulation and to make expert recommendations on issues such as the initiation and interruption of anticoagulation, quality of anticoagulation care, management of major and minor bleeding, and treatment of special populations. The attendees continued to work toward consensus on these topics, and present the key findings of this roundtable in a state-of- the-art review focusing on the practical aspects of anticoagulation care for the patient with atrial fibrillation. PMID:25835447

  3. [Improvements in oral anticoagulant therapy for atrial fibrillation].

    PubMed

    Briongos Figuero, Sem; García Santos-Gallego, Carlos; Badimón, Juan José

    2013-12-01

    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.

  4. Atrial fibrillation: what are the targets for intervention?

    PubMed

    Miller, John M; Olgin, Jeffrey E; Das, Mithilesh K

    2003-10-01

    Atrial fibrillation (AF) is a difficult and growing problem in the population. While medical therapy controls symptoms in many patients, a proportion of individuals with this common arrhythmia cannot be optimally managed with drugs alone. However, truly curative therapy for AF has always been one of the "holy grails" of electrophysiology. The surgical maze procedure was the first to offer permanent maintenance of sinus rhythm in patients with AF but subjected the patient to open heart surgery; a catheter-based translation of the maze procedure served as proof of concept that a catheterization technique could be used to treat AF. Subsequent experience has narrowed the electrophysiologist's attention to ablation of triggers of AF, most often residing in the pulmonary veins, rather than requiring more extensive ablation lines to control the arrhythmia. The following discussion deals with the development and current status of techniques for catheter ablation of atrial fibrillation, focusing on determination of appropriate target sites for ablation.

  5. Atrial fibrillation detection using stationary wavelet transform analysis.

    PubMed

    Weng, Binwei; Wang, John J; Michaud, Francis; Blanco-Velasco, Manuel

    2008-01-01

    Atrial fibrillation (AF) is a common cardiac arrythmia that is usually developed for elder people with aging. AF may result in complications such as chest pain or even heart failure in later stage. Based on the characteristics of surface ECG, AF can be detected by several methods. A particular investigation on the fibrillatory waveform reveals the inherent structure of AF signals. As opposed to traditional frequency domain methods, we utilize the stationary wavelet transform to extract the information from ECG signal which differentiates AF and non-AF cases based on some feature extraction and selection processes. A linear classifier is then designed for computational efficiency. The proposed method eliminates the need for QRST cancellation step which is required for frequency domain methods and provides a more systematic approach for AF detection. Extensive experiments are tested on signals from the MIT-BIH Atrial Fibrillation Database to show the superior performance of the proposed algorithm.

  6. Atrial fibrillation after taser exposure in a previously healthy adolescent.

    PubMed

    Multerer, Sara; Berkenbosch, John W; Das, Bibhuti; Johnsrude, Christopher

    2009-12-01

    We are reporting a previously healthy adolescent who developed atrial fibrillation after being tased. He has a structurally normal heart on echocardiogram, normal electrolyte level and thyroid function test results, and a urine toxicology screen positive for marijuana. The patient ultimately required external defibrillation to convert his cardiac rhythm to normal sinus rhythm and has had no recurrent arrhythmias since hospital discharge (approximately 1 year). This is the first reported case of atrial fibrillation developing after a Taser shot, occurring in an adolescent without other risk factors. This case illustrates the arrhythmogenic potential of a Taser in otherwise healthy young individuals, and further study of occurrence of Taser-induced arrhythmias is warranted. PMID:20016356

  7. Practical management of anticoagulation in patients with atrial fibrillation.

    PubMed

    Kovacs, Richard J; Flaker, Greg C; Saxonhouse, Sherry J; Doherty, John U; Birtcher, Kim K; Cuker, Adam; Davidson, Bruce L; Giugliano, Robert P; Granger, Christopher B; Jaffer, Amir K; Mehta, Bella H; Nutescu, Edith; Williams, Kim A

    2015-04-01

    Anticoagulation for atrial fibrillation has become more complex due to the introduction of new anticoagulant agents, the number and kinds of patients requiring therapy, and the interactions of those patients in the matrix of care. The management of anticoagulation has become a "team sport" involving multiple specialties in multiple sites of care. The American College of Cardiology, through the College's Anticoagulation Initiative, convened a roundtable of experts from multiple specialties to discuss topics important to the management of patients requiring anticoagulation and to make expert recommendations on issues such as the initiation and interruption of anticoagulation, quality of anticoagulation care, management of major and minor bleeding, and treatment of special populations. The attendees continued to work toward consensus on these topics, and present the key findings of this roundtable in a state-of- the-art review focusing on the practical aspects of anticoagulation care for the patient with atrial fibrillation.

  8. [Prevention of brain infarction in patients with atrial fibrillation].

    PubMed

    Ogata, Toshiyasu; Yasaka, Masahiro

    2007-01-01

    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.

  9. Dronedarone: evidence supporting its therapeutic use in the treatment of atrial fibrillation

    PubMed Central

    Sullivan, Renee M; Olshansky, Brian

    2010-01-01

    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

  10. The Mechanism of and Preventive Therapy for Stroke in Patients with Atrial Fibrillation

    PubMed Central

    Kim, Young-Hoon; Roh, Seung-Young

    2016-01-01

    Atrial fibrillation is a major cardiac cause of stroke, and a pathogenesis involving thrombus formation in patients with atrial fibrillation is well established. A strategy for rhythm control that involves catheter ablation and anticoagulation therapy is evolving. A strategy for rhythm control that restores and maintains sinus rhythm should reduce the risk of ischemic stroke that is associated with atrial fibrillation; however, this is yet to be proven in large-scale randomized controlled trials. This paper reviews the emerging role of rhythm control therapy for atrial fibrillation to prevent stroke. PMID:27283277

  11. Defining nonvalvular atrial fibrillation: A quest for clarification.

    PubMed

    Martins, Raphaël P; Galand, Vincent; Colette, Edouard; Behar, Nathalie; Pavin, Dominique; Leclercq, Christophe; Daubert, Jean-Claude; Mabo, Philippe

    2016-08-01

    Non-vitamin K oral anticoagulants (NOACs) are currently recommended for patients with nonvalvular atrial fibrillation since the publication of the 4 major pivotal trials evaluating the efficacy and safety of factor IIa and factor Xa inhibitors. The definition of nonvalvular atrial fibrillation is unclear, varying from one trial to another and even between North American and European guidelines, which is a source of uncertainties in clinical practice. However, many patients with atrial fibrillation present signs of valvular involvement, and clarification of this term is needed to not deny NOACs to patients based on the wrong perception that they may have valvular atrial fibrillation. The currently unique contraindications to NOACs are patients with mechanical heart valves and those with moderate-to-severe mitral stenosis, as stated by the recent 2015 position paper of the European Heart Rhythm Association. Patients with native heart valve involvement, regardless of their severity, are suitable for NOAC therapy. Patients with bioprosthetic heart valves and mitral valve repair may be suitable for NOACs except for the first 3 and the first 3-6 months postoperatively, respectively. Patients with transaortic valve implantation or percutaneous transluminal aortic valvuloplasty are also considered as being eligible for NOACs, although the bleeding risk has to be carefully considered in this population often requiring a combination with antiplatelet therapy. Future studies are warranted to increase the level of evidence of use of NOACs, particularly in patients with transaortic valve implantation and valvular surgery, and to determine whether they could be used in the future in the only 2 remaining contraindications. PMID:27502864

  12. Catapult launch-associated cardioversion of atrial fibrillation.

    PubMed

    Bohnker, B K; Feeks, E F; McEwen, G

    1993-10-01

    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.

  13. Atrial fibrillation and stroke management: present and future.

    PubMed

    Holmes, David R

    2010-11-01

    Stroke remains the leading cause of disability and the third leading cause of death. Despite advances in treatment, the early and later outcomes remain poor with a high rate of death and or disability. Strategies for prevention have assumed a central role. Given the close relationship between advancing age, atrial fibrillation, and increasing stroke, there is great interest in this large specific population of patients. Although warfarin has been the cornerstone of therapy for stroke prevention in patients with atrial fibrillation, it is often not used because of absolute or relative contraindications, or is ineffective because of poor control of the international normalized ratio (INR). The relative risk-benefit ratio of stroke prevention versus bleeding hazard plays a central role in therapeutic decisions. New pharmacologic approaches have been studied, most recently direct thrombin inhibitors. These drugs may be associated with less bleeding than warfarin, although there continues to be incremental bleeding risk over a patient's lifetime. In patients with nonvalvular atrial fibrillation, device strategies are being tested. These are based upon the information that in such patients, stroke arises from thrombus in the left atrial appendage in 90% of cases. Left atrial appendage occlusion has now been tested in a randomized clinical trial. In this trial, device closure was found to be noninferior to warfarin for prevention of all-cause stroke, cardiac death, and systemic embolization. There was an early safety hazard typically related to periprocedural pericardial effusions; however, subsequent experience has continued to document excellent efficacy and improved safety profiles. New randomized trials and registries continue to explore the potential for device placement as an alternative to anticoagulant therapy for stroke prevention in this group of patients.

  14. Artificial Intelligence Methods Applied to Parameter Detection of Atrial Fibrillation

    NASA Astrophysics Data System (ADS)

    Arotaritei, D.; Rotariu, C.

    2015-09-01

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

  15. Patient's Guide to Living with Atrial Fibrillation

    MedlinePlus

    ... fibrillation. Circulation . 2002 ; 106 : 14 –16. OpenUrl FREE Full Text ↵ The AFFIRM Investigators. Relationships between sinus rhythm, treatment, ... Circulation . 2004 ; 109 : 1509 –1513. OpenUrl Abstract / FREE Full Text ↵ Shea JB, Maisel WH. Cardioversion. Circulation . 2002 ; 106 : ...

  16. [Atrial fibrillation. New views on an old disease].

    PubMed

    Asensio-Lafuente, E; Alvarez-Mosquera, J B; Lozano-Díaz, J E; Farías-Vega, A; Narváez-David, R; Dorantes-García, J; Orea-Tejeda, A; Rebollar-González, V; Portos-Silva, J M; Oseguera-Moguel, J

    2001-01-01

    Atrial fibrillation (Afib) is clinically the most common arrhythmia. Its main complications are recurrent embolic events and a variable deterioration of functional class. Atrial fibrillation induces changes in cellular ionic channels that self-perpetuate the arrhythmia. The pharmacologic treatment of Afib is directed toward correction of those changes and return to sinus rhythm. It is also intended to maintain adequate heart rates and prevent embolic events through anticoagulation or platelet antiagregation. There are presently several class IC or class III antiarrhythmics available for attempting a return to sinus rhythm. The success rates are irregular, the best achieved with flecainide or propafenone among patients without structural heart disease. Amiodarone is the best choice when there is such a problem. The combination possibilities are huge, so that each case must be individualized. The new class III antiarrhythmics are very effective, but have a relatively high rate of side effects including torsade de pointes. Anticoagulation should be the preferred treatment among the majority of patients, but each case should be individually evaluated. New therapies such as focal or linear catheter ablation techniques, atrial or biatrial programmed stimulation, and atrial cardioverter-defibrillator need longer follow-up and experience to be objectively evaluated, although there are reasons to be optimistic in the future, even if patients need antiarrhythmic support at present. Surgery has high morbi-mortality rates, so it is not the preferred approach. PMID:11692812

  17. Atrial conduction delay predicts atrial fibrillation in paroxysmal supraventricular tachycardia patients after radiofrequency catheter ablation.

    PubMed

    Xu, Zhen-Xing; Zhong, Jing-Quan; Zhang, Wei; Yue, Xin; Rong, Bing; Zhu, Qing; Zheng, Zhaotong; Zhang, Yun

    2014-06-01

    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.

  18. Management of refractory atrial fibrillation post surgical ablation.

    PubMed

    Altman, Robert K; Proietti, Riccardo; Barrett, Conor D; Paoletti Perini, Alessandro; Santangeli, Pasquale; Danik, Stephan B; Di Biase, Luigi; Natale, Andrea

    2014-01-01

    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

  19. Management of refractory atrial fibrillation post surgical ablation

    PubMed Central

    Altman, Robert K.; Proietti, Riccardo; Barrett, Conor D.; Paoletti Perini, Alessandro; Santangeli, Pasquale; Danik, Stephan B.; Di Biase, Luigi

    2014-01-01

    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

  20. Outcomes after ablation for typical atrial flutter (from the Loire Valley Atrial Fibrillation Project).

    PubMed

    Clementy, Nicolas; Desprets, Laurent; Pierre, Bertrand; Lallemand, Bénédicte; Simeon, Edouard; Brunet-Bernard, Anne; Babuty, Dominique; Fauchier, Laurent

    2014-11-01

    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.

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

    PubMed

    Matějková, Adéla; Šteiner, Ivo

    2016-01-01

    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. PMID:27526304

  2. Left Atrial Size and Function in a Canine Model of Chronic Atrial Fibrillation and Heart Failure

    PubMed Central

    Goldberg, Adam; Kusunose, Kenya; Qamruddin, Salima; Rodriguez, L. Leonardo; Mazgalev, Todor N.; Griffin, Brian P.; Van Wagoner, David R.; Zhang, Youhua; Popović, Zoran B.

    2016-01-01

    Background Our aim was to assess how atrial fibrillation (AF) induction, chronicity, and RR interval irregularity affect left atrial (LA) function and size in the setting of underlying heart failure (HF), and to determine whether AF effects can be mitigated by vagal nerve stimulation (VNS). Methods HF was induced by 4-weeks of rapid ventricular pacing in 24 dogs. Subsequently, AF was induced and maintained by atrial pacing at 600 bpm. Dogs were randomized into control (n = 9) and VNS (n = 15) groups. In the VNS group, atrioventricular node fat pad stimulation (310 μs, 20 Hz, 3–7 mA) was delivered continuously for 6 months. LA volume and LA strain data were calculated from bi-weekly echocardiograms. Results RR intervals decreased with HF in both groups (p = 0.001), and decreased further during AF in control group (p = 0.014), with a non-significant increase in the VNS group during AF. LA size increased with HF (p<0.0001), with no additional increase during AF. LA strain decreased with HF (p = 0.025) and further decreased after induction of AF (p = 0.0001). LA strain decreased less (p = 0.001) in the VNS than in the control group. Beat-by-beat analysis showed a curvilinear increase of LA strain with longer preceding RR interval, (r = 0.45, p <0.0001) with LA strain 1.1% higher (p = 0.02) in the VNS-treated animals, independent of preceding RR interval duration. The curvilinear relationship between ratio of preceding and pre-preceding RR intervals, and subsequent LA strain was weaker, (r = 0.28, p = 0.001). However, VNS-treated animals again had higher LA strain (by 2.2%, p = 0.002) independently of the ratio of preceding and pre-preceding RR intervals. Conclusions In the underlying presence of pacing-induced HF, AF decreased LA strain, with little impact on LA size. LA strain depends on the preceding RR interval duration. PMID:26771573

  3. Left atrial electrophysiologic feature specific for the genesis of complex fractionated atrial electrogram during atrial fibrillation.

    PubMed

    Hoshiyama, Tadashi; Yamabe, Hiroshige; Koyama, Junjiroh; Kanazawa, Hisanori; Ogawa, Hisao

    2016-05-01

    Complex fractionated atrial electrogram (CFAE) has been suggested to contribute to the maintenance of atrial fibrillation (AF). However, electrophysiologic characteristics of the left atrial myocardium responsible for genesis of CFAE have not been clarified. Non-contact mapping of the left atrium was performed at 37 AF onset episodes in 24 AF patients. Electrogram amplitude, width, and conduction velocity were measured during sinus rhythm, premature atrial contraction (PAC) with long- (L-PAC), short- (S-PAC) and very short-coupling intervals (VS-PAC). These parameters were compared between CFAE and non-CFAE regions. Unipolar electrogram amplitude was higher in CFAE than non-CFAE during sinus rhythm, L-, S- and VS-PAC (1.82 ± 0.73 vs. 1.13 ± 0.38, p < 0.001; 1.44 ± 0.54 vs. 0.92 ± 0.35, p < 0.001; 1.09 ± 0.40 vs. 0.70 ± 0.27, p < 0.001; 0.76 ± 0.30 vs. 0.53 ± 0.25 mV, p < 0.001). Laplacian bipolar electrogram amplitude was also higher in CFAE than non-CFAE during sinus rhythm, L-, S- and VS-PAC. Unipolar electrogram width was similar in CFAE and non-CFAE. Laplacian bipolar electrogram width was wider in CFAE than non-CFAE during L-, S- and VS-PAC (85.5 ± 6.8 vs. 79.6 ± 4.5, p < 0.001; 96.1 ± 9.7 vs. 84.5 ± 5.9, p < 0.001; 122.4 ± 16.0 vs. 99.6 ± 9.6 ms, p < 0.001), but not during sinus rhythm. The conduction velocity was slower in CFAE during sinus rhythm, L-, S- and VS-PAC than non-CFAE (1.7 ± 0.3 vs. 2.4 ± 0.4, p < 0.001; 1.4 ± 0.3 vs. 2.0 ± 0.5, p < 0.001; 1.2 ± 0.3 vs. 1.7 ± 0.5, p < 0.001; and 0.9 ± 0.3 vs. 1.4 ± 0.4 m/s, p < 0.001). CFAE was generated in the high amplitude atrial myocardium with slow and non-uniform conduction properties which were pronounced associated with premature activation, suggesting that heterogeneous conduction produced in high amplitude region contributes to the genesis of CFAE.

  4. Novel P Wave Indices to Predict Atrial Fibrillation Recurrence After Radiofrequency Ablation for Paroxysmal Atrial Fibrillation

    PubMed Central

    Hu, Xiaoliang; Jiang, Jingzhou; Ma, Yuedong; Tang, Anli

    2016-01-01

    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

  5. Meta-analysis identifies six new susceptibility loci for atrial fibrillation

    PubMed Central

    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

    2012-01-01

    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

  6. Atrial fibrillation and coronary bypass surgery - what can be risk factors for its' appearance?

    PubMed

    Straus, Slavenka; Kacila, Mirsad; Omerbasic, Edin; Mujicic, Ermina

    2010-02-01

    The main goal of our study was to evaluate possible perioperative risk factors for occurrence of atrial fibrillation in the postoperative period in patients after CABG operations. The study included 140 patients after CABG, divided into two groups - Group I - 64 patients with new onset of POAF and Group II - 76 patients without postoperative atrial fibrillation occurrence. In both groups possible risk factors for atrial fibrillation onset (preoperative and postoperative) were analyzed.Results showed that we can predict new onset of atrial fibrillation after CABG if the following preoperative factors are present - low ejection fraction (less than 40%), LAd > 40mm, higher body mass index (BMI over 30), presence of COPD and older age. Important perioperative factors for onset of atrial fibrillation in our study were longer extracorporeal circulation, increased dose/number of inotropic drugs, blood transfusion and elevated WBC count postoperatively.

  7. Assessment of atrial fibrosis for the rhythm control of atrial fibrillation.

    PubMed

    Begg, Gordon A; Holden, Arun V; Lip, Gregory Y H; Plein, Sven; Tayebjee, Muzahir H

    2016-10-01

    Rhythm control of atrial fibrillation (AF) remains challenging, with modest long-term success rates. Atrial fibrosis has been associated with AF, but the clinical utility of assessment of this fibrosis has yet to be fully elucidated. In this paper we review the current state of understanding of the pathophysiology of atrial fibrosis in AF, and its impact upon the instigation and propagation of the arrhythmia. Fibrosis causes an increase in volume of dysfunctional extracellular matrix, and is associated with cellular alterations such as hypertrophy, apoptosis and membrane dysfunction within the atrial myocardium. In turn, these cause pathological alterations to atrial conduction, such as increased anisotropy, conduction block and re-entry, which can lead to AF. We review current methods of assessing atrial fibrosis and their impact upon the prediction of success of interventional rhythm control strategies such as ablation and cardioversion. We focus particularly on circulating biomarkers of fibrosis and scar formation; their role in the fibrotic process, and their value in the prediction of rhythm control success. We also review imaging and invasive electrocardiographic mapping techniques that may identify fibrosis, and again assess their potential predictive value. In this area there exist many unanswered questions, but further work will help to refine techniques to reliably identify and treat those patients who are most likely to benefit from rhythm control treatment strategies. PMID:27389440

  8. Current results of minimally invasive surgical ablation for isolated atrial fibrillation.

    PubMed

    Mack, Michael J

    2009-12-01

    The Cox maze surgical ablation operation is a highly effective treatment for patients with atrial fibrillation, but adoption has been limited by procedure complexity and invasiveness. Minimally invasive approaches using nonsternotomy limited access and eliminating cardiopulmonary bypass have been developed. All published series of minimally invasive surgical ablation for isolated, atrial fibrillation were reviewed. Series were analyzed for method of access, energy source, procedure success, and complications. Outcomes were compiled based on type of atrial fibrillation, method and length of follow-up, and freedom from atrial fibrillation with and without antiarrhythmic drugs. There are 14 published series with outcomes reported in 604 unique patients. Most procedures are performed through bilateral minithoracotomies with video assistance, although in later series a totally thoracoscopic approach is more commonly used. Bipolar radiofrequency is the predominant energy source used, and bilateral pulmonary vein isolation the most common lesion set, with some reports adding ganglionic plexi ablation and more extensive ablation lines. Approximately 53% of the procedures were performed for paroxysmal and 47% for persistent/long-standing persistent atrial fibrillation. Overall freedom from atrial fibrillation at 6-12 months is 84% (59%-91%), with 89% (79%-100%) in paroxysmal and 62% (25%-87%) in persistent/long-standing persistent patients. Overall freedom from atrial fibrillation off of antiarrhythmic drugs is 65% (57%-87%). Results approximating those of the Cox maze procedure are achieved with minimally invasive surgical ablation of atrial fibrillation in patients with paroxysmal atrial fibrillation. Further developments are necessary to further simplify and standardize the procedure, to replicate the results in larger series from more centers, to standardize the reporting of results, and to define a more effective procedure for persistent and long-standing persistent

  9. Atrial Fibrillation and Hypertension: Mechanistic, Epidemiologic, and Treatment Parallels

    PubMed Central

    Ogunsua, Adedotun A.; Shaikh, Amir Y.; Ahmed, Mohamed; McManus, David D.

    2015-01-01

    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. PMID:27057292

  10. [Pulmonary vein ablation in atrial fibrillation. Initial experience].

    PubMed

    Velarde, José Luis; Martellotto, Ricardo; Scanavacca, Mauricio; Arévalo, Aldo; Colque, Roberto; Jiménez, Marcelo

    2002-05-01

    Despite the progress in the knowledge of the pathophysiology of the atrial fibrillation (AF), the pharmacologic and non pharmacologic approach to prevent and control this arrhythmia has been shown to be discouraging. In the past few years a new type of AF has been described, of which the focal mechanism -especially bound to the pulmonary veins- allows ablation treatment through the radiofrequency (RF) with a catheter. We present our initial experience with this type of method, in two young patients who suffered from multiples episodes of AF and resistance to the conventional treatment. In both patients the RF ablation was done in the left superior pulmonary vein. One of them received an ablation in only one focus, and the other needed a veno-atrial disconnection through the elimination of the pulmonary venous potential from this vein. After three month of follow-up, patients remain asymptomatic with no relapse. PMID:12015937

  11. Atrial Fibrillation and Hypertension: Mechanistic, Epidemiologic, and Treatment Parallels.

    PubMed

    Ogunsua, Adedotun A; Shaikh, Amir Y; Ahmed, Mohamed; McManus, David D

    2015-01-01

    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. PMID:27057292

  12. Is Warfarin Really Underused in Patients with Atrial Fibrillation?

    PubMed Central

    Weisbord, Steven D; Whittle, Jeff; Brooks, Robert C

    2001-01-01

    CONTEXT There is agreement that warfarin decreases stroke risk in patients with atrial fibrillation (AF), but prior studies suggest that warfarin is markedly underused, for unclear reasons. OBJECTIVE To determine if warfarin is underused in the treatment of patients with atrial fibrillation. DESIGN Cross-sectional. SETTING Tertiary care VA hospital. PATIENTS All patients with a hospital or outpatient diagnosis of AF between 10/1/95 and 5/31/98. DATA COLLECTION One or more physician investigators reviewed pertinent records for each patient. When any of the 3 investigators thought warfarin might be indicated, the patient's primary care provider completed a survey regarding why warfarin was not used. RESULTS Of 1,289 AF patients, 844 (65%) had filled at least 1 warfarin prescription. Of the 445 remaining, 19 had died, 5 had inadequate medical records, and 54 received warfarin elsewhere, leaving 367 patients. Of these, 160 had no documented AF, 53 had only a history of AF, and 49 had only transient AF. Of the remaining 105 patients, 17 refused warfarin therapy and 72 had documented contraindications to warfarin use including bleeding risk or history, fall risk, alcohol abuse, or other compliance problems. The reasons for not using warfarin among the 16 patients remaining included provider oversight (n = 4) and various reasons suggesting provider knowledge deficits. CONCLUSION In contrast to prior studies that suggested that warfarin is markedly underused, we found that few patients with AF and no contraindication to anticoagulation were not receiving warfarin. We believe that differing study methodologies, including the use of physician review and provider survey, may explain our markedly different rate of warfarin underutilization, although local institutional factors cannot be excluded. The findings suggest that primary providers may be far more compliant with the standard of care for patients with atrial fibrillation than previously believed. PMID:11722687

  13. Personalized management of atrial fibrillation: Proceedings from the fourth Atrial Fibrillation competence NETwork/European Heart Rhythm Association consensus conference.

    PubMed

    Kirchhof, Paulus; Breithardt, Günter; Aliot, Etienne; Al Khatib, Sana; Apostolakis, Stavros; Auricchio, Angelo; Bailleul, Christophe; Bax, Jeroen; Benninger, Gerlinde; Blomstrom-Lundqvist, Carina; Boersma, Lucas; Boriani, Giuseppe; Brandes, Axel; Brown, Helen; Brueckmann, Martina; Calkins, Hugh; Casadei, Barbara; Clemens, Andreas; Crijns, Harry; Derwand, Roland; Dobrev, Dobromir; Ezekowitz, Michael; Fetsch, Thomas; Gerth, Andrea; Gillis, Anne; Gulizia, Michele; Hack, Guido; Haegeli, Laurent; Hatem, Stephane; Häusler, Karl Georg; Heidbüchel, Hein; Hernandez-Brichis, Jessica; Jais, Pierre; Kappenberger, Lukas; Kautzner, Joseph; Kim, Steven; Kuck, Karl-Heinz; Lane, Deirdre; Leute, Angelika; Lewalter, Thorsten; Meyer, Ralf; Mont, Lluis; Moses, Gregory; Mueller, Markus; Münzel, Felix; Näbauer, Michael; Nielsen, Jens Cosedis; Oeff, Michael; Oto, Ali; Pieske, Burkert; Pisters, Ron; Potpara, Tatjana; Rasmussen, Lars; Ravens, Ursula; Reiffel, James; Richard-Lordereau, Isabelle; Schäfer, Herbert; Schotten, Ulrich; Stegink, Wim; Stein, Kenneth; Steinbeck, Gerhard; Szumowski, Lukasz; Tavazzi, Luigi; Themistoclakis, Sakis; Thomitzek, Karen; Van Gelder, Isabelle C; von Stritzky, Berndt; Vincent, Alphons; Werring, David; Willems, Stephan; Lip, Gregory Y H; Camm, A John

    2013-11-01

    The management of atrial fibrillation (AF) has seen marked changes in past years, with the introduction of new oral anticoagulants, new antiarrhythmic drugs, and the emergence of catheter ablation as a common intervention for rhythm control. Furthermore, new technologies enhance our ability to detect AF. Most clinical management decisions in AF patients can be based on validated parameters that encompass type of presentation, clinical factors, electrocardiogram analysis, and cardiac imaging. Despite these advances, patients with AF are still at increased risk for death, stroke, heart failure, and hospitalizations. During the fourth Atrial Fibrillation competence NETwork/European Heart Rhythm Association (AFNET/EHRA) consensus conference, we identified the following opportunities to personalize management of AF in a better manner with a view to improve outcomes by integrating atrial morphology and damage, brain imaging, information on genetic predisposition, systemic or local inflammation, and markers for cardiac strain. Each of these promising avenues requires validation in the context of existing risk factors in patients. More importantly, a new taxonomy of AF may be needed based on the pathophysiological type of AF to allow personalized management of AF to come to full fruition. Continued translational research efforts are needed to personalize management of this prevalent disease in a better manner. All the efforts are expected to improve the management of patients with AF based on personalized therapy.

  14. Personalized management of atrial fibrillation: Proceedings from the fourth Atrial Fibrillation competence NETwork/European Heart Rhythm Association consensus conference.

    PubMed

    Kirchhof, Paulus; Breithardt, Günter; Aliot, Etienne; Al Khatib, Sana; Apostolakis, Stavros; Auricchio, Angelo; Bailleul, Christophe; Bax, Jeroen; Benninger, Gerlinde; Blomstrom-Lundqvist, Carina; Boersma, Lucas; Boriani, Giuseppe; Brandes, Axel; Brown, Helen; Brueckmann, Martina; Calkins, Hugh; Casadei, Barbara; Clemens, Andreas; Crijns, Harry; Derwand, Roland; Dobrev, Dobromir; Ezekowitz, Michael; Fetsch, Thomas; Gerth, Andrea; Gillis, Anne; Gulizia, Michele; Hack, Guido; Haegeli, Laurent; Hatem, Stephane; Häusler, Karl Georg; Heidbüchel, Hein; Hernandez-Brichis, Jessica; Jais, Pierre; Kappenberger, Lukas; Kautzner, Joseph; Kim, Steven; Kuck, Karl-Heinz; Lane, Deirdre; Leute, Angelika; Lewalter, Thorsten; Meyer, Ralf; Mont, Lluis; Moses, Gregory; Mueller, Markus; Münzel, Felix; Näbauer, Michael; Nielsen, Jens Cosedis; Oeff, Michael; Oto, Ali; Pieske, Burkert; Pisters, Ron; Potpara, Tatjana; Rasmussen, Lars; Ravens, Ursula; Reiffel, James; Richard-Lordereau, Isabelle; Schäfer, Herbert; Schotten, Ulrich; Stegink, Wim; Stein, Kenneth; Steinbeck, Gerhard; Szumowski, Lukasz; Tavazzi, Luigi; Themistoclakis, Sakis; Thomitzek, Karen; Van Gelder, Isabelle C; von Stritzky, Berndt; Vincent, Alphons; Werring, David; Willems, Stephan; Lip, Gregory Y H; Camm, A John

    2013-11-01

    The management of atrial fibrillation (AF) has seen marked changes in past years, with the introduction of new oral anticoagulants, new antiarrhythmic drugs, and the emergence of catheter ablation as a common intervention for rhythm control. Furthermore, new technologies enhance our ability to detect AF. Most clinical management decisions in AF patients can be based on validated parameters that encompass type of presentation, clinical factors, electrocardiogram analysis, and cardiac imaging. Despite these advances, patients with AF are still at increased risk for death, stroke, heart failure, and hospitalizations. During the fourth Atrial Fibrillation competence NETwork/European Heart Rhythm Association (AFNET/EHRA) consensus conference, we identified the following opportunities to personalize management of AF in a better manner with a view to improve outcomes by integrating atrial morphology and damage, brain imaging, information on genetic predisposition, systemic or local inflammation, and markers for cardiac strain. Each of these promising avenues requires validation in the context of existing risk factors in patients. More importantly, a new taxonomy of AF may be needed based on the pathophysiological type of AF to allow personalized management of AF to come to full fruition. Continued translational research efforts are needed to personalize management of this prevalent disease in a better manner. All the efforts are expected to improve the management of patients with AF based on personalized therapy. PMID:23981824

  15. The Intrinsic Autonomic Nervous System in Atrial Fibrillation: A Review

    PubMed Central

    He, Bo; Scherlag, Benjamin J.; Nakagawa, Hiroshi; Lazzara, Ralph; Po, Sunny S.

    2012-01-01

    The procedure of catheter ablation for the treatment of drug resistant atrial fibrillation (AF) has evolved but still relies on lesion sets intended to isolate areas of focal firing, mainly the myocardial sleeves of the pulmonary veins (PVs), from the rest of the atria. However the success rates for this procedure have varied inversely with the type of AF. At best success rates have been 20 to 30% below that of other catheter ablation procedures for Wolff-Parkinson-White syndrome, atrioventricular junctional re-entrant tachycardia and atrial flutter. Basic and clinical evidence has emerged suggesting a critical role of the ganglionated plexi (GP) at the PV-atrial junctions in the initiation and maintenance of the focal form of AF. At present the highest success rates have been obtained with the combination of PV isolation and GP ablation both as catheter ablation or minimally invasive surgical procedures. Various lines of evidence from earlier and more recent reports provide that both neurally based and myocardially based forms of AF can separately dominate or coexist within the context of atrial remodeling. Future studies are focusing on non-pharmacological, non-ablative approaches for the prevention and treatment of AF in order to avoid the substantive complications of both these regimens. PMID:22778995

  16. The exploitation of spatial topographies for atrial signal extraction in atrial fibrillation ECGs.

    PubMed

    Bonizzi, Pietro; Phlypo, Ronald; Zarzoso, Vicente; Meste, Olivier

    2008-01-01

    The accuracy in the extraction of the atrial activity (AA) from electrocardiogram (ECG) signals recorded during atrial fibrillation (AF) episodes plays an important role in the analysis and characterization of atrial arrhythmias. The present contribution puts forward a method for AA signal extraction based on a blind source separation (BSS) formulation. The latter exploits spatial information on the different components in the ECG related or not to AF. The source directions or spatial topographies of the components not related to AF are used to determine the nullspace of the AA, so that the topographies related to AA become more suitable to describe AF sources. The comparative performance of the method is evaluated on real data recorded from patients with noticeable AF. The AA extraction quality of the proposed technique is comparable to that of previous algorithms.

  17. Is percutaneous closure of the left atrial appendage comparable to anticoagulants for atrial fibrillation?

    PubMed

    Uslar, Thomas; Anabalón, Jaime

    2015-01-01

    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. PMID:26335602

  18. Is percutaneous closure of the left atrial appendage comparable to anticoagulants for atrial fibrillation?

    PubMed

    Uslar, Thomas; Anabalón, Jaime

    2015-08-17

    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.

  19. Acute atrial fibrillation in emergency surgery: Is it rare?

    PubMed

    Ankichetty, Saravanan; Nandhakumar, Amar; Subramanyam, Rajeev; Venkatraghavan, Lashmi

    2011-05-01

    Atrial fibrillation (AF) is a common arrhythmia with an estimated clinical prevalence of approximately 1% in the general population and as high as 9% in individuals by the age of 80 years. The aetiology is multifactorial. Systemic disease, e.g., inflammatory processes, sarcoidosis, autoimmune disorders, has also been linked to the development of AF. Myocardial dysfunction observed in sepsis could contribute to arrhythmias and inflammation per se could induce or provoke AF. We describe the successful management of an acute AF in an elderly patient scheduled for emergency laparotomy and closure of hollow viscous perforation.

  20. [Oral anticoagulation in chronic kidney disease with atrial fibrillation].

    PubMed

    Expósito, Víctor; Seras, Miguel; Fernández-Fresnedo, Gema

    2015-05-21

    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.

  1. Non-Vitamin K Antagonist Oral Anticoagulants in Atrial Fibrillation.

    PubMed

    Plitt, Anna; Ruff, Christian T; Giugliano, Robert P

    2016-10-01

    For more than 50 years, vitamin K antagonists (VKAs) have been the standard of care for treatment of atrial fibrillation (AF). However, the numerous limitations of VKAs have led to the development of non-VKA oral anticoagulants (NOACs). There are 4 NOACs currently approved for prevention of thromboembolism in patients with nonvalvular AF. This article provides an overview of AF, summarizes basic properties of NOACs, and reviews the landmark trials. Current data on use of NOACs in special populations and specific clinical scenarios are also presented. Lastly, recommendations from experts on controversial topics of bleeding management and reversal are described. PMID:27637305

  2. Early detection of occult atrial fibrillation and stroke prevention.

    PubMed

    Keach, Joseph Walker; Bradley, Steven M; Turakhia, Mintu P; Maddox, Thomas M

    2015-07-01

    Atrial fibrillation (AF) is a very common arrhythmia and significantly increases stroke risk. This risk can be mitigated with oral anticoagulation, but AF is often asymptomatic, or occult, preventing timely detection and treatment. Accordingly, occult AF may cause stroke before it is clinically diagnosed. Currently, guidelines for the early detection and treatment of occult AF are limited. This review addresses recent advancements in occult AF detection methods, identification of populations at high risk for occult AF, the treatment of occult AF with oral anticoagulation, as well as ongoing trials that may answer critically important questions regarding occult AF screening.

  3. Emerging Tools for Stroke Prevention in Atrial Fibrillation.

    PubMed

    Voukalis, Christos; Lip, Gregory Y H; Shantsila, Eduard

    2016-02-01

    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

  4. [Oral anticoagulation in chronic kidney disease with atrial fibrillation].

    PubMed

    Expósito, Víctor; Seras, Miguel; Fernández-Fresnedo, Gema

    2015-05-21

    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. PMID:24889748

  5. Emerging Tools for Stroke Prevention in Atrial Fibrillation

    PubMed Central

    Voukalis, Christos; Lip, Gregory Y.H.; Shantsila, Eduard

    2016-01-01

    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

  6. Ablation Technology for the Surgical Treatment of Atrial Fibrillation

    PubMed Central

    Melby, Spencer J.; Schuessler, Richard B.; Damiano, Ralph J.

    2014-01-01

    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

  7. Dronedarone for the treatment of atrial fibrillation and atrial flutter: approval and efficacy

    PubMed Central

    Wolbrette, Deborah; Gonzalez, Mario; Samii, Soraya; Banchs, Javier; Penny-Peterson, Erica; Naccarelli, Gerald

    2010-01-01

    Dronedarone, a new Class III antiarrhythmic agent, has now been approved by the US Food and Drug Administration for use in patients with atrial fibrillation or atrial flutter. Approval came in March 2009 due to the positive results of the ATHENA trial showing significant reductions in all-cause mortality and cardiovascular hospitalization with dronedarone use. A post hoc analysis of the ATHENA data also suggested a decrease in stroke risk with this agent. However, due to safety concerns in the heart failure population in the earlier ANDROMEDA trial, dronedarone is not recommended for patients with an ejection fraction <35% and recent decompensated heart failure. Dronedarone is an amiodarone analog with multichannel blocking electrophysiologic properties similar to those of amiodarone, but several structural differences. Dronedarone’s lack of the iodine moiety reduces its potential for thyroid and pulmonary toxicity. Preliminary data from the DIONYSOS trial, and an indirect meta-analysis comparing amiodarone with dronedarone, showed amiodarone to be more effective in maintaining sinus rhythm, while dronedarone was associated with fewer adverse effects resulting in early termination of the drug. Dronedarone is the first antiarrhythmic drug for the treatment of atrial fibrillation and atrial flutter shown to reduce cardiovascular hospitalizations. In patients with structural heart disease who have an ejection fraction >35% and no recent decompensated heart failure, dronedarone should be considered earlier than amiodarone in the treatment algorithm. PMID:20730068

  8. Localized reentrant tachycardia in the aorta contiguity region mimicking perimitral atrial flutter in the context of atrial fibrillation ablation.

    PubMed

    Ejima, Koichiro; Shoda, Morio; Miyazaki, Shinsuke; Yashiro, Bun; Wakisaka, Osamu; Manaka, Tetsuyuki; Hagiwara, Nobuhisa

    2013-07-01

    We describe a case with a focal atrial tachycardia (AT) masquerading as perimitral atrial flutter revealed after circumferential pulmonary vein antral isolation for atrial fibrillation. It was successfully terminated and became noninducible by a point ablation on the left atrial anterior wall (LAAW) near the mitral annulus in contact with the aortic root and on the left superior pulmonary vein-left atrial appendage ridge, without any linear ablation, using electroanatomical mapping and conventional precise mapping with a maximum amplified gain within the low-voltage area. The AT revealed in our case was an LAAW-aorta contiguity area-related AT.

  9. Incidence and prognostic significance of atrial fibrillation in acute myocardial infarction: the GISSI-3 data

    PubMed Central

    Pizzetti, F; Turazza, F; Franzosi, M; Barlera, S; Ledda, A; Maggioni, A; Santoro, L; Tognoni, G

    2001-01-01

    BACKGROUND—Atrial fibrillation is the most common supraventricular arrhythmia in patients with acute myocardial infarction. Recent advances in pharmacological treatment of myocardial infarction may have changed the impact of this arrhythmia.
OBJECTIVE—To assess the incidence and prognosis of atrial fibrillation complicating myocardial infarction in a large population of patients receiving optimal treatment, including angiotensin converting enzyme (ACE) inhibitors.
METHODS—Data were derived from the GISSI-3 trial, which included 17 944 patients within the first 24 hours after acute myocardial infarction. Atrial fibrillation was recorded during the hospital stay, and follow up visits were planned at six weeks and six months. Survival of the patients at four years was assessed through census offices.
RESULTS—The incidence of in-hospital atrial fibrillation or flutter was 7.8%. Atrial fibrillation was associated with indicators of a worse prognosis (age > 70 years, female sex, higher Killip class, previous myocardial infarction, treated hypertension, high systolic blood pressure at entry, insulin dependent diabetes, signs or symptoms of heart failure) and with some adverse clinical events (reinfarction, sustained ventricular tachycardia, ventricular fibrillation). After adjustment for other prognostic factors, atrial fibrillation remained an independent predictor of increased in-hospital mortality: 12.6% v 5%, adjusted relative risk (RR) 1.98, 95% confidence interval (CI) 1.67 to 2.34. Data on long term mortality (four years after acute myocardial infarction) confirmed the persistent negative influence of atrial fibrillation (RR 1.78, 95% CI 1.60 to 1.99).
CONCLUSIONS—Atrial fibrillation is an indicator of worse prognosis after acute myocardial infarction, both in the short term and in the long term, even in an unselected population.


Keywords: atrial fibrillation; acute myocardial infarction; prognosis PMID:11602545

  10. Internal cardioversion of persistent atrial fibrillation using rectilinear biphasic waveform.

    PubMed

    Mairesse, Georges H; Raepers, Monique; Legrand, Isabelle; Baroud, Imad; Deheneffe, Yvon; Emonts, Michel; Paquay, Jean-Louis; Mitri, Kamal

    2003-12-01

    Internal electrical cardioversion is currently used in patients with persistent atrial fibrillation resistant to external electrical cardioversion. In external cardioversion, biphasic waveforms have shown a greater efficacy than monomorphic waveforms. The present study aimed to test the safety and efficacy of rectilinear biphasic waveform in converting patients with persistent atrial fibrillation to sinus rhythm using internal electrical cardioversion, and to compare it with that of classical monophasic waveform. Twenty-seven consecutive patients with persistent AF received 31 internal cardioversions, using monophasic waveform in 11 (group I), and rectilinear biphasic waveform in 20 cases (group II). Baseline patients characteristics were similar in both groups. Multipolar catheters were positioned in the distal coronary sinus and in the high right atrium. Synchronised shocks were delivered using an escalating protocol of 2, 5, 10, 15, 20, 30, and 50 Joules. In group I, 1 patient was resistant to maximal energy (success rate 91%). The mean energy of the maximal shock was 18 +/- 13 J. In group II, all patients were converted to sinus rhythm. The mean energy of the maximal shock was 9 +/- 5 J (p < 0.01 vs. group I). No significant complications occurred. At 3 months follow-up, 45% of group I and 60% of group II patients remained in sinus rhythm (p = NS). We conclude that internal cardioversion using rectilinear biphasic waveform is feasible and safe, and requires less energy than classical monophasic waveforms. PMID:14618059

  11. Totally implantable robot to treat chronic atrial fibrillation.

    PubMed

    Tozzi, Piergiorgio; Hayoz, Daniel; Thévenaz, Pierrick; Roulet, Jean-Yves; Salchli, Francois; von Segesser, Ludwig K

    2008-09-01

    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

  12. Fish, Marine n−3 Fatty Acids, and Atrial Fibrillation – Experimental Data and Clinical Effects

    PubMed Central

    Rix, Thomas Andersen; Mortensen, Lotte Maxild; Schmidt, Erik Berg

    2012-01-01

    Marine n−3 polyunsaturated fatty acids (PUFA) may have beneficial effects in relation to atrial fibrillation (AF) with promising data from experimental animal studies, however, results from studies in humans have been inconsistent. This review evaluates the mechanisms of action of marine n−3 PUFA in relation to AF based on experimental data and provides a status on the evidence obtained from observational studies and interventional trials. In conclusion, there is growing evidence for an effect of marine n−3 PUFA in prevention and treatment of AF. However, further studies are needed to establish which patients are more likely to benefit from n−3 PUFA, the timing of treatment, and dosages. PMID:22654766

  13. Atrial Fibrillation Ablation by Use of Electroanatomical Mapping: Efficacy and Recurrence Factors

    PubMed Central

    Kalil, Carlos; Bartholomay, Eduardo; Borges, Anibal; Gazzoni, Guilherme; de Lima, Edimar; Etchepare, Renata; Moraes, Rafael; Sussenbach, Carolina; Andrade, Karina; Kalil, Renato

    2014-01-01

    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

  14. Change in P wave morphology after convergent atrial fibrillation ablation.

    PubMed

    Shrestha, Suvash; Chen, On; Greene, Mary; John, Jinu Jacob; Greenberg, Yisachar; Yang, Felix

    2016-01-01

    Convergent atrial fibrillation ablation involves extensive epicardial as well as endocardial ablation of the left atrium. We examined whether it changes the morphology of the surface P wave. We reviewed electrocardiograms of 29 patients who underwent convergent ablation for atrial fibrillation. In leads V1, II and III, we measured P wave duration, area and amplitude before ablation, and at 1, 3 and 6 months from ablation. After ablation, there were no significant changes in P wave amplitude, area, or duration in leads II and III. There was a significant reduction in the area of the terminal negative deflection of the P wave in V1 from 0.38 mm(2) to 0.13 mm(2) (p = 0.03). There is also an acute increase in the amplitude and duration of the positive component of the P wave in V1 followed by a reduction in both by 6 months. Before ablation, 62.5% of the patients had biphasic P waves in V1. In 6 months, only 39.2% of them had biphasic P waves. Hybrid ablation causes a reduction of the terminal negative deflection of the P wave in V1 as well as temporal changes in the duration and amplitude of the positive component of the P wave in V1. This likely reflects the reduced electrical contribution of the posterior left atrium after ablation as well as anatomical and autonomic remodeling. Recognition of this altered sinus P wave morphology is useful in the diagnosis of atrial arrhythmias in this patient population. PMID:27485559

  15. Noninvasive characterization of atrioventricular conduction in patients with atrial fibrillation.

    PubMed

    Corino, Valentina D A; Sandberg, Frida; Mainardi, Luca T; Platonov, Pyotr G; Sörnmo, Leif

    2015-01-01

    The atrioventricular (AV) node plays a fundamental role in patients with atrial fibrillation (AF), acting as a filter to the numerous irregular atrial impulses which bombard the node. A phenomenological approach to better understand AV nodal electrophysiology is to analyze the ventricular response with respect to irregularity. In different cohorts of AF patients, such analysis has been performed with the aim to evaluate the association between ventricular response characteristics and long-term clinical outcome and to determine whether irregularity is affected by rate-control drugs. Another approach to studying AV nodal characteristics is to employ a mathematical model which accounts for the refractory periods of the two AV nodal pathways. With atrial fibrillatory rate and RR intervals as input, the model has been considered for analyzing data during (i) rest and head-up tilt test, (ii) tecadenoson and esmolol, and (iii) rate-control drugs. The present paper provides an overview of our recent work on the characterization and assessment of AV nodal conduction using these two approaches. PMID:26324177

  16. The role of the autonomic ganglia in atrial fibrillation

    PubMed Central

    Stavrakis, Stavros; Nakagawa, Hiroshi; Po, Sunny S.; Scherlag, Benjamin J.; Lazzara, Ralph; Jackman, Warren M.

    2015-01-01

    Recent experimental and clinical studies have shown that the epicardial autonomic ganglia play an important role in the initiation and maintenance of atrial fibrillation (AF). In this review, we present the current data on the role of the autonomic ganglia in the pathogenesis of AF and discuss potential therapeutic implications. Experimental studies have demonstrated that acute autonomic remodeling may play a crucial role in AF maintenance in the very early stages. The benefit of adding ablation of the autonomic ganglia to the standard pulmonary vein (PV) isolation procedure for patients with paroxysmal AF is supported by both experimental and clinical data. The interruption of axons from these hyperactive autonomic ganglia to the PV myocardial sleeves may be an important factor in the success of PV isolation procedures. The vagus nerve exerts an inhibitory control over the autonomic ganglia and attenuation or loss of this control may allow these ganglia to become hyperactive. Autonomic neuromodulation using low-level vagus nerve stimulation inhibits the activity of the autonomic ganglia and reverses acute electrical atrial remodeling during rapid atrial pacing and may provide an alternative non-ablative approach for the treatment of AF, especially in the early stages. This notion is supported by a preliminary human study. Further studies are warranted to confirm these findings. PMID:26301262

  17. Catheter ablation of atrial fibrillation in the elderly

    PubMed Central

    Lioni, Louiza; Letsas, Konstantinos P.; Efremidis, Michael; Vlachos, Konstantinos; Giannopoulos, Georgios; Kareliotis, Vasileios; Deftereos, Spyridon; Sideris, Antonios

    2014-01-01

    Background Atrial fibrillation (AF) catheter ablation has emerged as a promising treatment strategy for AF, but has not been widely adopted in the elderly population. The present study aimed to determine the safety and efficacy of AF catheter ablation in the elderly population. Methods and Results The study population consisted of 316 patients with paroxysmal AF who underwent left atrial ablation. Ninety-five patients were ≥ 65 years (48 males, mean age 68.9 ± 3.0 years old) and 221 patients were < 65 years old (130 males, mean age 52.5 ± 10.4 years old). After a mean follow-up period of 34.0 ± 15.1 months, 55 (57.9%) patients in the elderly group were free from arrhythmia recurrence compared with 149 (67.4%) patients in the younger group (P = 0.169). Procedural complications were uncommon in both study groups. In logistic regression analysis, left atrial diameter (P = 0.003), hypertension (P = 0.001), dyslipidemia (P = 0.039), and coronary artery disease (P = 0.018) were independent predictors of AF recurrence in the elderly population. Conclusions Catheter ablation of AF is safe and effective in older patients. Invasive strategies should be considered as an alternative choice in symptomatic elderly patients with AF. PMID:25593577

  18. Prolonged and fractionated right atrial electrograms during sinus rhythm in patients with paroxysmal atrial fibrillation and sick sinus node syndrome.

    PubMed

    Tanigawa, M; Fukatani, M; Konoe, A; Isomoto, S; Kadena, M; Hashiba, K

    1991-02-01

    Intraatrial catheter mapping of the right atrium was performed during sinus rhythm in 92 patients: Group I = 43 control patients without paroxysmal atrial fibrillation or sick sinus node syndrome; Group II = 31 patients with paroxysmal atrial fibrillation but without sick sinus node syndrome; and Group III = 18 patients with both paroxysmal atrial fibrillation and sick sinus node syndrome. Atrial electrograms were recorded at 12 sites in the right atrium. The duration and number of fragmented deflections of the atrial electrograms were quantitatively measured. The mean duration and number of fragmented deflections of the 516 atrial electrograms in Group I were 74 +/- 11 ms and 3.9 +/- 1.3, respectively. The criteria for an abnormal atrial electrogram were defined as a duration of greater than or equal to 100 ms or eight or more fragmented deflections, or both. Abnormal atrial electrograms were observed in 10 patients (23.3%) in Group I, 21 patients (67.7%) in Group II and 15 patients (83.3%) in Group III (Group II versus Group I, p less than 0.001; Group III versus Group I, p less than 0.001). The mean number of abnormal electrograms per patient with an abnormal electrogram was 1.3 +/- 0.7 in Group I, 2.5 +/- 1.9 in Group II and 3.5 +/- 2.5 in Group III (Group I versus Group II, p less than 0.01; Group II versus Group III, p less than 0.05). A prolonged and fractionated atrial electrogram characteristic of paroxysmal atrial fibrillation can be closely related to the vulnerability of the atrial muscle.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. A prospective randomized study to assess the efficacy of rate and site of atrial pacing on long-term development of atrial fibrillation.

    PubMed

    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

    2009-09-01

    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. PMID:19460078

  20. Fifty-Year Trends in Atrial Fibrillation Prevalence, Incidence, Risk Factors, and Mortality in the Community

    PubMed Central

    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

    2015-01-01

    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

  1. Atrial fibrillation and heart failure: natural history and pharmacological treatment.

    PubMed

    Savelieva, Irina; John Camm, A

    2004-09-01

    Atrial fibrillation (AF) is the most common sustained arrhythmia. Congestive heart failure (CHF), an increasingly frequent cardiovascular disorder affecting millions of people world-wide, has become the most important risk factor of AF in developed countries, as a result of ageing populations. Approximately two thirds of patients with CHF are >65 years of age and likely to have AF as a coexistent complication. Epidemiological surveys and large clinical trials in CHF provide strong evidence that AF is a marker of increased mortality. AF may compromise LV systolic function and worsen CHF through poor rate control, irregularity of ventricular response, and loss of atrial systolic activity. Furthermore, enhanced adrenergic stimulation in the setting of CHF facilitates AV conduction and promotes the progression of cardiomyopathy, and AF may worsen CHF as a consequence of the negative inotropic effects of drugs used to control the heart rate of rhythm, or of the proarrhythmic effects of drugs used to maintain sinus rhythm. This article reviews the putative mechanisms behind atrial remodelling due to long-standing AF, and the role of neuro-hormonal alterations in the atrial electrophysiologic and structural changes which facilitate its perpetuation. It also reviews and discusses various controlled trials of angiotensin-converting enzyme inhibitors and AT-1 receptor blockade in the perspective of AF treatment and prevention. Finally the role of specific antiarrhythmic drugs, the respective advantages and shortcomings of rate versus rhythm control in patients with AF and CHF, and the important issue of chronic anticoagulation are presented in the light of time-tested therapies, as well as new promising therapeutic approaches.

  2. Common Genetic Variants and Response to Atrial Fibrillation Ablation

    PubMed Central

    Shoemaker, M. Benjamin; Bollmann, Andreas; Lubitz, Steven A.; Ueberham, Laura; Saini, Harsimran; Montgomery, Jay; Edwards, Todd; Yoneda, Zachary; Sinner, Moritz F.; Arya, Arash; Sommer, Philipp; Delaney, Jessica; Goyal, Sandeep K.; Saavedra, Pablo; Kanagasundram, Arvindh; Whalen, S. Patrick; Roden, Dan M.; Hindricks, Gerhard; Ellis, Christopher R.; Ellinor, Patrick T.; Darbar, Dawood; Husser, Daniela

    2016-01-01

    Background Common single nucleotide polymorphisms (SNPs) at chromosomes 4q25 (rs2200733, rs10033464 near PITX2), 1q21 (rs13376333 in KCNN3), and 16q22 (rs7193343 in ZFHX3) have consistently been associated with the risk of atrial fibrillation (AF). Single-center studies have shown that 4q25 risk alleles predict recurrence of AF after catheter ablation of AF. Here, we performed a meta-analysis to test the hypothesis that these 4 AF susceptibility SNPs modulate response to AF ablation. Methods and Results Patients underwent de novo AF ablation between 2008 and 2012 at Vanderbilt University, the Heart Center Leipzig, and Massachusetts General Hospital. The primary outcome was 12-month recurrence, defined as an episode of AF, atrial flutter, or atrial tachycardia lasting >30 seconds after a 3-month blanking period. Multivariable analysis of the individual cohorts using a Cox proportional hazards model was performed. Summary statistics from the 3 centers were analyzed using fixed effects meta-analysis. A total of 991 patients were included (Vanderbilt University, 245; Heart Center Leipzig, 659; and Massachusetts General Hospital, 87). The overall single procedure 12-month recurrence rate was 42%. The overall risk allele frequency for these SNPs ranged from 12% to 35%. Using a dominant genetic model, the 4q25 SNP, rs2200733, predicted a 1.4-fold increased risk of recurrence (adjusted hazard ratio, 1.3 [95% confidence intervals, 1.1–1.6]; P=0.011). The remaining SNPs, rs10033464 (4q25), rs13376333 (1q21), and rs7193343 (16q22) were not significantly associated with recurrence. Conclusions Among the 3 genetic loci most strongly associated with AF, the chromosome 4q25 SNP rs2200733 is significantly associated with recurrence of atrial arrhythmias after catheter ablation for AF. PMID:25684755

  3. Atrial Fibrillation Ablation in Systolic Dysfunction: Clinical and Echocardiographic Outcomes

    PubMed Central

    Lobo, Tasso Julio; Pachon, Carlos Thiene; Pachon, Jose Carlos; Pachon, Enrique Indalecio; Pachon, Maria Zelia; Pachon, Juan Carlos; Santillana, Tomas Guillermo; Zerpa, Juan Carlos; Albornoz, Remy Nelson; Jatene, Adib Domingos

    2015-01-01

    Background Heart failure and atrial fibrillation (AF) often coexist in a deleterious cycle. Objective To evaluate the clinical and echocardiographic outcomes of patients with ventricular systolic dysfunction and AF treated with radiofrequency (RF) ablation. Methods Patients with ventricular systolic dysfunction [ejection fraction (EF) <50%] and AF refractory to drug therapy underwent stepwise RF ablation in the same session with pulmonary vein isolation, ablation of AF nests and of residual atrial tachycardia, named "background tachycardia". Clinical (NYHA functional class) and echocardiographic (EF, left atrial diameter) data were compared (McNemar test and t test) before and after ablation. Results 31 patients (6 women, 25 men), aged 37 to 77 years (mean, 59.8±10.6), underwent RF ablation. The etiology was mainly idiopathic (19 p, 61%). During a mean follow-up of 20.3±17 months, 24 patients (77%) were in sinus rhythm, 11 (35%) being on amiodarone. Eight patients (26%) underwent more than one procedure (6 underwent 2 procedures, and 2 underwent 3 procedures). Significant NYHA functional class improvement was observed (pre-ablation: 2.23±0.56; postablation: 1.13±0.35; p<0.0001). The echocardiographic outcome also showed significant ventricular function improvement (EF pre: 44.68%±6.02%, post: 59%±13.2%, p=0.0005) and a significant left atrial diameter reduction (pre: 46.61±7.3 mm; post: 43.59±6.6 mm; p=0.026). No major complications occurred. Conclusion Our findings suggest that AF ablation in patients with ventricular systolic dysfunction is a safe and highly effective procedure. Arrhythmia control has a great impact on ventricular function recovery and functional class improvement. PMID:25387404

  4. Atrial fibrillation in rats induced by rapid transesophageal atrial pacing during brief episodes of asphyxia: a new in vivo model.

    PubMed

    Haugan, Ketil; Lam, Henrik Rye; Knudsen, Carsten Boye; Petersen, Jørgen Søberg

    2004-07-01

    Non-pharmacological in vivo models of atrial fibrillation (AF) have been developed in large animals only. We aimed to develop and characterize a new small animal non-pharmacological in vivo model of AF. AF was induced by transesophageal atrial burst pacing during 35 seconds periods of asphyxia in anesthetized male Sprague-Dawley rats. AF was reproducibly induced in 81% of the rats. The presence of AF was associated with an increased heart rate, and a decreased blood pressure. Treatment with amiodarone, D,L-sotalol, flecainide, and propranolol all reduced duration of AF, whereas verapamil treatment was associated with a marked profibrillatory effect. Increasing gap junction intracellular communication using the antiarrhythmic peptide analogue AAP10 did not affect AF duration. Basal plasma level of epinephrine and norepinephrine were increased 5- to 20-fold relative to values reported by others, but unchanged following 35 seconds of asphyxia. The results from our study demonstrate that the rat model shares several clinical key characteristics with human AF: (1) hemodynamic response to AF; (2) increased autonomic tone; (3) antiarrhythmic effects of clinically used drugs; (4) profibrillatory effect of verapamil. Relative to existing models of AF in larger animals, this model offers rapid, predictive, and inexpensive testing of antiarrhythmic/profibrillatory effects of new drugs.

  5. Effects of Electrical and Structural Remodeling on Atrial Fibrillation Maintenance: A Simulation Study

    PubMed Central

    Krogh-Madsen, Trine; Abbott, Geoffrey W.; Christini, David J.

    2012-01-01

    Atrial fibrillation, a common cardiac arrhythmia, often progresses unfavourably: in patients with long-term atrial fibrillation, fibrillatory episodes are typically of increased duration and frequency of occurrence relative to healthy controls. This is due to electrical, structural, and contractile remodeling processes. We investigated mechanisms of how electrical and structural remodeling contribute to perpetuation of simulated atrial fibrillation, using a mathematical model of the human atrial action potential incorporated into an anatomically realistic three-dimensional structural model of the human atria. Electrical and structural remodeling both shortened the atrial wavelength - electrical remodeling primarily through a decrease in action potential duration, while structural remodeling primarily slowed conduction. The decrease in wavelength correlates with an increase in the average duration of atrial fibrillation/flutter episodes. The dependence of reentry duration on wavelength was the same for electrical vs. structural remodeling. However, the dynamics during atrial reentry varied between electrical, structural, and combined electrical and structural remodeling in several ways, including: (i) with structural remodeling there were more occurrences of fragmented wavefronts and hence more filaments than during electrical remodeling; (ii) dominant waves anchored around different anatomical obstacles in electrical vs. structural remodeling; (iii) dominant waves were often not anchored in combined electrical and structural remodeling. We conclude that, in simulated atrial fibrillation, the wavelength dependence of reentry duration is similar for electrical and structural remodeling, despite major differences in overall dynamics, including maximal number of filaments, wave fragmentation, restitution properties, and whether dominant waves are anchored to anatomical obstacles or spiralling freely. PMID:22383869

  6. Atrial Fibrillation: A Review of Recent Studies with a Focus on Those from the Duke Clinical Research Institute

    PubMed Central

    Rao, Meena P.; Pokorney, Sean D.; Granger, Christopher B.

    2014-01-01

    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

  7. Chronic spinal cord stimulation modifies intrinsic cardiac synaptic efficacy in the suppression of atrial fibrillation

    PubMed Central

    Ardell, Jeffrey L.; Cardinal, René; Beaumont, Eric; Vermeulen, Michel; Smith, Frank M.; Armour, J. Andrew

    2014-01-01

    We sought to determine whether spinal cord stimulation (SCS) therapy, when applied chronically to canines, imparts long-lasting cardio-protective effects on neurogenic atrial tachyarrhythmia induction and, if so, whether its effects can be attributable to i) changes in intrinsic cardiac (IC) neuronal transmembrane properties vs ii) modification of their interneuronal stochastic interactivity that initiates such pathology. Data derived from canines subjected to long-term SCS [(group 1 studied after 3–4 weeks SCS; n=5) (group 2: studied 5 weeks SCS; n=11)] were compared to data derived from 10 control animals (including 4 sham SCS electrode implantations). During terminal studies conducted under anesthesia, chronotropic and inotropic responses to vagal nerve or stellate ganglion stimulation were similar in all 3 groups. Chronic SCS suppressed atrial tachyarrhythmia induction evoked by mediastinal nerve stimulation. When induced, arrhythmia durations were shortened (controls: median of 27s; SCS 3–4 weeks: median of 16s; SCS 5 weeks: median of 7s). Phasic and accommodating right atrial neuronal somata displayed similar passive and active membrane properties in vitro, whether derived from sham or either chronic SCS groups. Synaptic efficacy was differentially enhanced in accommodating (not phasic) IC neurons by chronic SCS. Taken together these data indicate that chronic SCS therapy modifies IC neuronal stochastic inter-connectivity in atrial fibrillation suppression by altering synaptic function without directly targeting the transmembrane properties of individual IC neuronal somata. PMID:25301713

  8. [Modern drug therapy of atrial fibrillation: selection of treatment strategy, antiarrhythmic preparations, and schemes of treatment].

    PubMed

    Kanorskiĭ, S G

    2012-01-01

    This review presents novel literature data on drug treatment of atrial fibrillation. We discuss here choice of strategy of therapy, antiarrhythmic drugs, and algorithms of preventive measures aimed at prevention of recurrences of this arrhythmia.

  9. 78 FR 11207 - Clinical Study Designs for Surgical Ablation Devices for Treatment of Atrial Fibrillation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-15

    ... clinical trial designs for surgical ablation devices intended for the treatment of atrial fibrillation... September 14, 2009 (74 FR 46996), FDA announced the availability of the draft guidance document....

  10. Atrial fibrillation in a healthy adolescent after heavy smoking of contraband cigarettes.

    PubMed

    Ozyilmaz, Isa; Ozyilmaz, Sinem; Tosun, Oyku; Tola, Hasan Tahsin; Saygi, Murat; Ergul, Yakup

    2015-08-01

    The use of contraband cigarettes is a serious public health problem. We present a case of atrial fibrillation in a healthy adolescent suspected to be caused by smoking contraband cigarettes. A 15-year-old man was admitted to our emergency department experiencing syncope and palpitations. He was a cigarette smoker, but he had never smoked any illicit tobacco products before. He had finished a pack of counterfeit cigarettes (20 pieces) in 1.5 h. His electrocardiogram showed atrial fibrillation with a rapid ventricular response and irregular RR intervals. The patient had no history of alcohol use, surgery, palpitations, hypertension, chronic bronchitis, or any infectious diseases. His atrial fibrillation was converted to a normal sinus rhythm after the cardioversion treatment. Our patient was discharged from the pediatric cardiology service and advised to quit smoking cigarettes, strictly warning against illicit tobacco products. In conclusion, intensive smoking of counterfeit cigarettes may lead to occurrences of atrial fibrillation.

  11. Clinical strategies for selecting oral anticoagulants in patients with atrial fibrillation

    PubMed Central

    Sherwood, Matthew W.; Becker, Richard C.

    2014-01-01

    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

  12. Personalizing oral anticoagulant treatment in patients with atrial fibrillation.

    PubMed

    Capranzano, Piera; Miccichè, Eligio; D'Urso, Lucia; Privitera, Fiorella; Tamburino, Corrado

    2013-08-01

    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. PMID:23957907

  13. Signal processing techniques for atrial fibrillation source detection.

    PubMed

    Ambadkar, Minal; Leonelli, Fabio M; Sankar, Ravi

    2014-01-01

    In clinical practice, Atrial Fibrillation (AF) is the most common and critical cardiac arrhythmia encountered. The treatment that can ensure permanent AF removal is catheter ablation, where cardiologists destroy the affected cardiac muscle cells with RF or Laser. In this procedure it is necessary to know exactly from which part of the heart AF triggers are originated. Various signal processing algorithms provide a strong tool to track AF sources. This study proposes, signal processing techniques that can be exploited for characterization, analysis and source detection of AF signals. These algorithms are implemented on Electrocardiogram (ECG) and intracardiac signals which contain important information that allows the analysis of anatomic and physiologic aspects of the whole cardiac muscle. PMID:25570578

  14. Antithrombotic treatment in elderly patients with atrial fibrillation.

    PubMed

    Suárez Fernández, C; Camafort, M; Cepeda Rodrigo, J M; Díez-Manglano, J; Formiga, F; Pose Reino, A; Tiberio, G; Mostaza, J M

    2015-04-01

    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. PMID:25618495

  15. Antithrombotic treatment in elderly patients with atrial fibrillation.

    PubMed

    Suárez Fernández, C; Camafort, M; Cepeda Rodrigo, J M; Díez-Manglano, J; Formiga, F; Pose Reino, A; Tiberio, G; Mostaza, J M

    2015-04-01

    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.

  16. Current clinical practice guidelines in atrial fibrillation: a review.

    PubMed

    Galvez-Olortegui, José Kelvin; Álvarez-Vargas, Mayita Lizbeth; Galvez-Olortegui, Tomas Vladimir; Godoy-Palomino, Armando; Camacho-Saavedra, Luis

    2016-01-14

    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.

  17. The management of atrial fibrillation in heart failure.

    PubMed

    Bala, Rupa; Callans, David J

    2006-08-01

    The development of atrial fibrillation (AF) can greatly complicate the course of heart failure (HF). Although recent trials have indicated the nonsuperiority of a rhythm control strategy in the general population with AF, this may not apply to patients with HF. We feel strongly that AF be treated aggressively in patients with HF, defaulting toward an initial rhythm control strategy, to avoid the hemodynamic detriment of irregular rapid ventricular response and the development of tachycardia-related myopathy. The index episode is treated with cardioversion and antiarrhythmic therapy. If significant benefit is demonstrated, the rhythm control strategy is maintained, to the point of catheter ablation for AF if necessary. If there is no change in cardiac performance or symptoms after cardioversion, strict rate control is enforced, to the point of atrioventricular node ablation and pacing if necessary.

  18. Current clinical practice guidelines in atrial fibrillation: a review.

    PubMed

    Galvez-Olortegui, José Kelvin; Álvarez-Vargas, Mayita Lizbeth; Galvez-Olortegui, Tomas Vladimir; Godoy-Palomino, Armando; Camacho-Saavedra, Luis

    2016-01-01

    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. PMID:26939036

  19. Emerging directions in the genetics of atrial fibrillation.

    PubMed

    Tucker, Nathan R; Ellinor, Patrick T

    2014-04-25

    Atrial fibrillation (AF) is the most common arrhythmia and is associated with increased morbidity. As the population ages and the prevalence of AF continues to rise, the socioeconomic consequences of AF will become increasingly burdensome. Although there are well-defined clinical risk factors for AF, a significant heritable component is also recognized. To identify the molecular basis for the heritability of AF, investigators have used a combination of classical Mendelian genetics, candidate gene screening, and genome-wide association studies. However, these avenues have, as yet, failed to define the majority of the heritability of AF. The goal of this review is to describe the results from both candidate gene and genome-wide studies, as well as to outline potential future avenues for creating a more complete understanding of AF genetics. Ultimately, a more comprehensive view of the genetic underpinnings for AF will lead to the identification of novel molecular pathways and improved risk prediction of this complex arrhythmia. PMID:24763465

  20. [Afobasol efficacy in a model of vagotonic atrial fibrillation].

    PubMed

    Stoliaruk, V N; Vititnova, M B; Tsorin, I B; Kryzhanovskiĭ, S A

    2010-01-01

    The new anxiolytic agent afobasol (Russia) was introduced into clinical practice by V. V. Zakusov Research Institute of Pharmacology. When administered to cats with vagotonic atrial fibrillation afobasol (7.5 mg/kg v/v) exhibited anti-arrhythmic activity at least as high as that of class 1 and III anti-arrhythmic agents (etacisin and cardiocyclide respectively) (Vaughan Williams classification). However, duration of its action was much smaller. These experimental findings were confirmed in clinical studies involving patients with severe psychosomatic pathology associated with paroxysmal flutter. It is supposed that afobasol activates cytosolic sigma-1 receptors in cardiomyocytes and may be used to manage psychoasthenic conditions accompanied by cardioneuroses and/or cardiophobias with disturbed rhythmic activity of the heart.

  1. Surgical perspectives in the management of atrial fibrillation

    PubMed Central

    Kyprianou, Katerina; Pericleous, Agamemnon; Stavrou, Antonio; Dimitrakaki, Inetzi A; Challoumas, Dimitrios; Dimitrakakis, Georgios

    2016-01-01

    Atrial fibrillation (AF) is the most common cardiac arrhythmia and a huge public health burden associated with significant morbidity and mortality. For decades an increasing number of patients have undergone surgical treatment of AF, mainly during concomitant cardiac surgery. This has sparked a drive for conducting further studies and researching this field. With the cornerstone Cox-Maze III “cut and sew” procedure being technically challenging, the focus in current literature has turned towards less invasive techniques. The introduction of ablative devices has revolutionised the surgical management of AF, moving away from the traditional surgical lesions. The hybrid procedure, a combination of catheter and surgical ablation is another promising new technique aiming to improve outcomes. Despite the increasing number of studies looking at various aspects of the surgical management of AF, the literature would benefit from more uniformly conducted randomised control trials. PMID:26839656

  2. [Social impact of stroke due to atrial fibrillation].

    PubMed

    Santamarina, E; Alvarez Sabín, J

    2012-03-01

    Atrial fibrillation (AF) is the most frequent heart arrhythmia and causes a substantial proportion of ischemic strokes. AF has a marked impact on stroke severity, as well as on morbidity and mortality in these patients. The importance of AF as an etiologic factor of stroke increases in the elderly and in the last few years its detection has increased. The presence of AF leads to more severe initial neurological involvement, longer hospitalization, greater disability and a lower probability of discharge to home. In addition, AF is an independent risk factor for mortality, especially in women and the elderly. All these factors lead to a higher social and economic impact among stroke patients with AF.

  3. Lone or idiopathic atrial fibrillation, messenger of misery in sight.

    PubMed

    Weijs, B; Crijns, H J G M

    2014-12-20

    This editorial refers to 'Gender-related differences in risk of cardiovascular morbidity and all-cause mortality in patients hospitalized with incident atrial fibrillation without concomitant diseases: a nationwide cohort study of 9519 patients' by T. Andersson et al. In order to adequately describe root causes and adverse consequences of apparently idiopathic AF, the requested study population has to be large and be followed for a very long time. Andersson et al. adequately deployed the excellent national Swedish health registries in order to cover the hiatus of aforementioned studies in the current idiopathic AF literature. Considering the notion that patients with idiopathic or lone AF have comparable prospects as AF patients overall but are only caught early in their 'arrhythmia and vascular career', the study by Andersson et al. should trigger physicians to give high priority to exposing predisposing factors or early stages of underlying cardiovascular disease in such a way that preventative measures can be accurately deployed in these patients.

  4. [Anticoagulation for patients with non-valvular atrial fibrillation].

    PubMed

    Mizoguchi, Tadataka; Yasaka, Masahiro

    2016-04-01

    Non-valvular atrial fibrillation (NVAF) is the most common cardiac source of emboli in cardioembolic stroke which occupies from 1/4 to 1/3 of acute brain infarction in Japan. Non-vitamin K antagonist oral anticoagulants (NOAC) have been used widely because they are easy to use, their effect in preventing ischemic stroke is higher than or as high as warfarin, their incidence of major hemorrhage is lower than or as low as warfarin, and their incidence of intracranial hemorrhage is much lower than warfarin. However, there seem several issues to address regarding NOAC treatment, such as reversal of anticoagulation, antidotes, monitoring of anticoagulation, rt-PA treatment for acute stroke patients treated with NOACs. In this review, current strategies and issues of anticoagulation for prevention of stroke in NVAF are discussed. PMID:27333751

  5. Signal processing techniques for atrial fibrillation source detection.

    PubMed

    Ambadkar, Minal; Leonelli, Fabio M; Sankar, Ravi

    2014-01-01

    In clinical practice, Atrial Fibrillation (AF) is the most common and critical cardiac arrhythmia encountered. The treatment that can ensure permanent AF removal is catheter ablation, where cardiologists destroy the affected cardiac muscle cells with RF or Laser. In this procedure it is necessary to know exactly from which part of the heart AF triggers are originated. Various signal processing algorithms provide a strong tool to track AF sources. This study proposes, signal processing techniques that can be exploited for characterization, analysis and source detection of AF signals. These algorithms are implemented on Electrocardiogram (ECG) and intracardiac signals which contain important information that allows the analysis of anatomic and physiologic aspects of the whole cardiac muscle.

  6. Management of atrial fibrillation in the emergency department.

    PubMed

    Crozier, I; Melton, I; Pearson, S

    2003-04-01

    Abstract Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and is a frequent cause for presentation to the emergency department. With an understanding of the pathophysiology and types of AF, efficient and effective management strategies for AF can be formulated. Patients with paroxysmal AF will often revert spontaneously and can initially be managed on an outpatient basis, unless an antiarrhythmic is commenced. In patients with AF and severe underlying heart disease, the management is primarily directed at the underlying heart disease, supplemented with rate-controlling measures, and prevention of thromboembolic complications. In patients with persistent AF good rate control, early cardioversion and initiation of an antiarrhythmic are likely to reduce the risk of recurrence. PMID:12680985

  7. Physician's Fear of Anticoagulant Therapy in Nonvalvular Atrial Fibrillation

    PubMed Central

    Dahlberg, Katherine Willett

    2014-01-01

    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

  8. Anti-Thrombotic Management of Atrial Fibrillation in the Elderly

    PubMed Central

    Edholm, Karli; Ragle, Nathan; Rondina, Matthew T.

    2014-01-01

    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

  9. Personalizing oral anticoagulant treatment in patients with atrial fibrillation.

    PubMed

    Capranzano, Piera; Miccichè, Eligio; D'Urso, Lucia; Privitera, Fiorella; Tamburino, Corrado

    2013-08-01

    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.

  10. The occurrence of postoperative atrial fibrillation according to different surgical settings in cardiac surgery patients

    PubMed Central

    Jakubová, Marta; Mitro, Peter; Stančák, Branislav; Sabol, František; Kolesár, Adrián; Cisarik, Paul; Nagy, Vincent

    2012-01-01

    OBJECTIVES Atrial fibrillation is the most common arrhythmia after cardiac surgery. The pathogenesis of postoperative atrial fibrillation is multifactorial. The aim of the study was to analyse preoperative, intraoperative and postoperative factors and their relationships with the occurrence and duration of atrial fibrillation. METHODS One hundred and ninety-six patients with coronary heart disease (152 men, age 62.7 ± 10.1 years) underwent surgical revascularization. Extracorporeal circulation was used in 64 patients and minimal extracorporeal circulation was used in 75 patients. Fifty-seven patients underwent surgery without extracorporeal circulation. During the first three postoperative days, subjects were monitored for the duration and incidence of atrial fibrillation, laboratory markers of inflammation (C-reactive protein, leucocytes) and serum potassium. RESULTS Demographic data and associated cardiovascular diseases in the groups were not statistically different. The overall incidence of atrial fibrillation was 56% (110 patients). The highest incidence of atrial fibrillation was found in the extracorporeal circulation subgroup, with a significantly lower incidence using minimal extracorporeal circulation, and in patients operated on without extracorporeal circulation (75 vs 47 vs 46%, P <0.001). The longest duration of atrial fibrillation was found in patients operated on with extracorporeal circulation compared with minimal extracorporeal circulation, and without extracorporeal circulation (9.7 ± 11.6 vs 4.9 ± 8.3 vs 3.1 ± 5.2, P ≤0.001). The incidence of postoperative atrial fibrillation significantly correlated with elevation of inflammatory markers (C-reactive protein, leucocytes) compared with patients who were free of atrial fibrillation (P ≤0.001, P ≤0.05). The values of serum potassium were not significantly different. The relationship between postoperative atrial fibrillation and echocardiographic parameters was not confirmed

  11. New classification scheme for atrial fibrillation symptom severity and burden.

    PubMed

    Koci, Florian; Forbes, Peter; Mansour, Moussa C; Heist, E Kevin; Singh, Jagmeet P; Ellinor, Patrick T; Ruskin, Jeremy N

    2014-07-15

    Although atrial fibrillation (AF) symptom severity is used to guide clinical care, a simple, standardized assessment tool is not available for routine clinical use. We sought to develop and validate a patient-generated score and classification scheme for AF-related symptom severity and burden. Atrial Fibrillation Symptom and Burden, a simple 2-part questionnaire, was designed to assess (1) AF symptom severity using 8 questions to determine how symptoms affect daily life and (2) AF burden using 6 questions to measure AF frequency, duration, and health-care utilization. The resulting score was used to classify patients into 4 classes of symptom and burden severity. Patients were asked to complete the questionnaire, a survey evaluating the questionnaire, and an Short Form-12v2 generic health-related quality-of-life form. Validation of the questionnaire included assessments of its reliability and construct and known groups validity. The strength of interrater agreement between patient-generated and blinded provider-generated classifications of AF symptom severity was also assessed. The survey had good internal consistency (Cronbach α>0.82) and reproducibility (intraclass correlation coefficient=0.93). There was a good linear correlation with health-related quality-of-life aggregates measured by Pearson correlation coefficient (r=0.62 and 0.42 vs physical component summary and mental component summary, respectively). Compared with physical and mental component summary scores, the patient-generated symptom severity classification scheme showed robust discrimination between mild and moderate severity (p<0.0001 and p=0.0009) and between moderate and severe groups (p=0.0001 and p=0.012). In conclusion, this simple patient-generated AF classification scheme is robust, internally consistent, reproducible, and highly correlated with standardized quality-of-life measures. PMID:24878121

  12. Nonpharmacologic management of atrial fibrillation: role of the pulmonary veins and posterior left atrium.

    PubMed

    Shivkumar, Kalyanam; Buch, Eric; Boyle, Noel G

    2009-12-01

    Nonpharmacologic approaches for the management of atrial fibrillation are rapidly emerging as the mainstay for definitive management of this arrhythmia. Over the past several years, numerous studies reported in the literature have highlighted various aspects of the pathophysiologic mechanisms underlying atrial fibrillation. The purpose of this review is to place the current approaches being used for arrhythmia management in the context of the current knowledge of about arrhythmia mechanisms.

  13. Usefulness of transoesophageal echocardiography before cardioversion in patients with atrial fibrillation and different anticoagulant regimens

    PubMed Central

    Maltagliati, A; Galli, C A; Tamborini, G; Calligaris, A; Doria, E; Salehi, R; Pepi, M

    2006-01-01

    Objectives To evaluate the prevalence of atrial thrombi in patients with atrial fibrillation undergoing different anticoagulation regimens before cardioversion; to evaluate the usefulness of transoesophageal echocardiography (TOE) guided cardioversion to prevent thromboembolic complications; and to correlate the presence of atrial thrombi with clinical and echocardiographic data. Methods 757 consecutive patients admitted as candidates for cardioversion of atrial fibrillation were enrolled in the study. They were divided into four groups: effective conventional oral anticoagulation, short term anticoagulation, ineffective oral anticoagulation or subtherapeutic anticoagulation, and effective oral anticoagulation with a duration of < 3 weeks for various clinical reasons. All patients underwent TOE before cardioversion; in the presence of atrial thrombi or extreme left atrial echo contrast, cardioversion was postponed. The incidence of thromboembolic events was evaluated after cardioversion. Results Atrial thrombi were detected in 48 of the 757 (6.3%) patients. No significant differences in the percentage of atrial thrombosis were found in the four study groups. Patients with atrial thrombosis were older and had a higher percentage of mitral prosthetic valves, lower left ventricular ejection fraction, more severe atrial spontaneous echo contrast, and lower Doppler left atrial appendage velocities. 648 patients were scheduled for cardioversion. Cardioversion was successful in 89% of patients without any major thromboembolic event. Conclusions The prevalence of atrial thrombosis before cardioversion despite different treatments with anticoagulants is about 7% and a TOE guided approach may prevent the risk of embolic events. PMID:16284221

  14. Disrupted calcium release as a mechanism for atrial alternans associated with human atrial fibrillation.

    PubMed

    Chang, Kelly C; Bayer, Jason D; Trayanova, Natalia A

    2014-12-01

    Atrial fibrillation (AF) is the most common cardiac arrhythmia, but our knowledge of the arrhythmogenic substrate is incomplete. Alternans, the beat-to-beat alternation in the shape of cardiac electrical signals, typically occurs at fast heart rates and leads to arrhythmia. However, atrial alternans have been observed at slower pacing rates in AF patients than in controls, suggesting that increased vulnerability to arrhythmia in AF patients may be due to the proarrythmic influence of alternans at these slower rates. As such, alternans may present a useful therapeutic target for the treatment and prevention of AF, but the mechanism underlying alternans occurrence in AF patients at heart rates near rest is unknown. The goal of this study was to determine how cellular changes that occur in human AF affect the appearance of alternans at heart rates near rest. To achieve this, we developed a computational model of human atrial tissue incorporating electrophysiological remodeling associated with chronic AF (cAF) and performed parameter sensitivity analysis of ionic model parameters to determine which cellular changes led to alternans. Of the 20 parameters tested, only decreasing the ryanodine receptor (RyR) inactivation rate constant (kiCa) produced action potential duration (APD) alternans seen clinically at slower pacing rates. Using single-cell clamps of voltage, fluxes, and state variables, we determined that alternans onset was Ca2+-driven rather than voltage-driven and occurred as a result of decreased RyR inactivation which led to increased steepness of the sarcoplasmic reticulum (SR) Ca2+ release slope. Iterated map analysis revealed that because SR Ca2+ uptake efficiency was much higher in control atrial cells than in cAF cells, drastic reductions in kiCa were required to produce alternans at comparable pacing rates in control atrial cells. These findings suggest that RyR kinetics may play a critical role in altered Ca2+ homeostasis which drives proarrhythmic

  15. Genetic Loci Associated With Atrial Fibrillation: Relation to Left Atrial Structure in the Framingham Heart Study

    PubMed Central

    Magnani, Jared W.; Yin, Xiaoyan; McManus, David D.; Chuang, Michael L.; Cheng, Susan; Lubitz, Steven A.; Arora, Garima; Manning, Warren J.; Ellinor, Patrick T.; Benjamin, Emelia J.

    2014-01-01

    Background Atrial fibrillation (AF) results in significant morbidity and mortality. Genome‐wide association studies (GWAS) have identified genetic variants associated with AF. Whether genetic variants associated with AF are also associated with atrial structure, an intermediate phenotype for AF, has had limited investigation. We sought to investigate associations between single nucleotide polymorphisms (SNPs) and atrial structure obtained by cardiovascular imaging in the Framingham Heart Study. Methods and Results We selected 11 SNPs that have been associated with AF in GWAS. We examined the SNPs' relations to cross‐sectional left atrial (LA) dimensions (determined by transthoracic echocardiography) and LA volume (determined by cardiovascular magnetic resonance [CMR]) employing linear regression. The total sample included 1555 participants with CMR LA volume (age 60±9 years, 53% women) and 6861 participants with echocardiographic LA diameter (age 48±13 years, 52% women) measured. We employed a significance threshold of P<0.0023 to account for multiple testing of the 11 SNPs and 2 LA measures. In a primary analysis, no SNPs were significantly related to the LA measures. Likewise, in secondary analyses excluding individuals with prevalent AF (n=77, CMR sample; n=105, echocardiography sample) no SNPs were related to LA volume or diameter. Conclusion In a community‐based cohort, we did not identify a statistically significant association between selected SNPs associated with AF and measures of LA anatomy. Further investigations with larger longitudinally assessed samples and a broader array of SNPs may be necessary to determine the relation between genetic loci associated with AF and atrial structure. PMID:24695651

  16. Prevalence of left atrial abnormalities in atrial fibrillation versus normal sinus patients

    PubMed Central

    Ketai, Loren H; Teague, Shawn D; Rissing, Stacy M

    2016-01-01

    Background Atrial fibrillation (AF) may be the cause or sequela of left atrial abnormalities and variants. Purpose To determine the prevalence of left atrial (LA) abnormalities in AF patients compared to normal sinus rhythm (NSR) patients. Material and Methods We retrospectively reviewed 281 cardiac CT examinations from 2010 to 2012, excluding patients with prior pulmonary vein ablation, known coronary artery disease, prior coronary stent placement, or coronary artery bypass grafts. The first group consisted of 159 AF patients undergoing cardiac CT prior to pulmonary vein ablation and the second group consisted of 122 NSR patients evaluated with coronary CT angiography. Demographic data were collected. LA abnormalities were analyzed. Left atrial diameter was measured on an axial view. Results A total of 281 patients were included. The male gender has significantly higher prevalence of AF than female gender, P value <0.001. Patients with AF were significantly older (mean age, 57.4 years; standard deviation [SD], 11.8 years) than NSR patients (mean age, 53.4 years; SD, 13.6 years), P value, 0.01. The left atrial diameter was greater in the AF patients (mean diameter, 4.3 cm; SD, 0.82 cm) versus the NSR patients (3.4 cm; SD, 0.58 cm), P value, <0.0001. LA diverticulum was the most prevalent variant, occurring in 28.4% of the entire patient population followed by LA pouch, occurring in 24%. There was no significant between group differences in the prevalence of these or the remainder of the LA variants. Conclusion AF patients differed significantly from NSR patients in LA size, gender, and mean age. There was no statistical significance between the two groups with regard to the LA morphologic abnormalities other than size. PMID:27358747

  17. Aberrant sodium influx causes cardiomyopathy and atrial fibrillation in mice

    PubMed Central

    Wan, Elaine; Abrams, Jeffrey; Weinberg, Richard L.; Katchman, Alexander N.; Bayne, Joseph; Zakharov, Sergey I.; Yang, Lin; Morrow, John P.; Garan, Hasan; Marx, Steven O.

    2015-01-01

    Increased sodium influx via incomplete inactivation of the major cardiac sodium channel NaV1.5 is correlated with an increased incidence of atrial fibrillation (AF) in humans. Here, we sought to determine whether increased sodium entry is sufficient to cause the structural and electrophysiological perturbations that are required to initiate and sustain AF. We used mice expressing a human NaV1.5 variant with a mutation in the anesthetic-binding site (F1759A-NaV1.5) and demonstrated that incomplete Na+ channel inactivation is sufficient to drive structural alterations, including atrial and ventricular enlargement, myofibril disarray, fibrosis and mitochondrial injury, and electrophysiological dysfunctions that together lead to spontaneous and prolonged episodes of AF in these mice. Using this model, we determined that the increase in a persistent sodium current causes heterogeneously prolonged action potential duration and rotors, as well as wave and wavelets in the atria, and thereby mimics mechanistic theories that have been proposed for AF in humans. Acute inhibition of the sodium-calcium exchanger, which targets the downstream effects of enhanced sodium entry, markedly reduced the burden of AF and ventricular arrhythmias in this model, suggesting a potential therapeutic approach for AF. Together, our results indicate that these mice will be important for assessing the cellular mechanisms and potential effectiveness of antiarrhythmic therapies. PMID:26595809

  18. Post-operative atrial fibrillation: a maze of mechanisms

    PubMed Central

    Maesen, Bart; Nijs, Jan; Maessen, Jos; Allessie, Maurits; Schotten, Ulrich

    2012-01-01

    Post-operative atrial fibrillation (POAF) is one of the most frequent complications of cardiac surgery and an important predictor of patient morbidity as well as of prolonged hospitalization. It significantly increases costs for hospitalization. Insights into the pathophysiological factors causing POAF have been provided by both experimental and clinical investigations and show that POAF is ‘multi-factorial’. Facilitating factors in the mechanism of the arrhythmia can be classified as acute factors caused by the surgical intervention and chronic factors related to structural heart disease and ageing of the heart. Furthermore, some proarrhythmic mechanisms specifically occur in the setting of POAF. For example, inflammation and beta-adrenergic activation have been shown to play a prominent role in POAF, while these mechanisms are less important in non-surgical AF. More recently, it has been shown that atrial fibrosis and the presence of an electrophysiological substrate capable of maintaining AF also promote the arrhythmia, indicating that POAF has some proarrhythmic mechanisms in common with other forms of AF. The clinical setting of POAF offers numerous opportunities to study its mechanisms. During cardiac surgery, biopsies can be taken and detailed electrophysiological measurements can be performed. Furthermore, the specific time course of POAF, with the delayed onset and the transient character of the arrhythmia, also provides important insight into its mechanisms. This review discusses the mechanistic interaction between predisposing factors and the electrophysiological mechanisms resulting in POAF and their therapeutic implications. PMID:21821851

  19. The history of atrial fibrillation: the last 100 years.

    PubMed

    Prystowsky, Eric N

    2008-06-01

    Atrial fibrillation (AF) has had a rich history that has touched the careers of many of the great clinicians and investigators of the 20th century. More recently, there has been an explosion of research into various aspects of the mechanisms and therapy for AF, as evidenced by over 8,000 publications on AF from 2000 to 2007. A century of research and clinical observations, coupled with modern investigative technologies, has enabled modern investigators to have their own "fantastic voyage" as they travel beyond the cell borders into the ionic mechanisms responsible for AF and its many atrial perturbations. One can only imagine the satisfaction of Wenckebach, MacKenzie, and Lewis if they could see how their seeds of wisdom have grown into such sturdy ideas, or how delighted Scherf would be to learn that his ectopic focus theory for AF has been given new life. This paper on 100 years of AF was initially prepared for presentation as the Plenary Lecture at the AFib Summit for Heart Rhythm 2007 in Denver, Colorado. I have tried to provide the reader with some of the most important observations on AF, realizing that it would be impossible to include all or even most of the major research done during this time frame. I apologize to my many colleagues whose research has helped us to understand better the clinical and basic aspects of AF, yet who could not be cited for lack of space.

  20. New technologies in treatment of atrial fibrillation in cardiosurgical patients

    NASA Astrophysics Data System (ADS)

    Evtushenko, A. V.; Evtushenko, V. V.; Bykov, A. N.; Sergeev, V. S.; Syryamkin, V. I.; Kistenev, Yu. V.; Anfinogenova, Ya. D.; Smyshlyaev, K. A.; Kurlov, I. O.

    2015-11-01

    The article is devoted to the evaluation of the results of clinical application of penetrating radiofrequency ablation techniques on atrial myocardium. Total operated on 241 patients with valvular heart disease and coronary heart disease complicated with atrial fibrillation. All operations were performed under cardiopulmonary bypass and cardioplegia. The main group consists of 141 patients which were operated using penetrating technique radiofrequency exposure. The control group consisted of 100 patients who underwent surgery with the use of "classical" monopolar RF-ablation technique. Both groups were not significantly different on all counts before surgery. Patients with previous heart surgery were excluded during the selection of candidates for the procedure, due to the presence of adhesions in the pericardium, that do not allow good visualization of left atrium, sufficient to perform this procedure. Penetrating technique has significantly higher efficiency compared to the "classic" technique in the early and long-term postoperative periods. In the early postoperative period, its efficiency is 93%, and in the long term is 88%. The efficacy of "classical" monopolar procedure is below: 86% and 68% respectively.

  1. Multifractal analysis for grading complex fractionated electrograms in atrial fibrillation.

    PubMed

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

    2015-11-01

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

  2. Pitx2, an Atrial Fibrillation Predisposition Gene, Directly Regulates Ion Transport and Intercalated Disc Genes

    PubMed Central

    Tao, Ye; Zhang, Min; Li, Lele; Bai, Yan; Zhou, Yuefang; Moon, Anne M.; Kaminski, Henry J.; Martin, James F.

    2014-01-01

    Background Pitx2 is the homeobox gene located in proximity to the human 4q25 familial atrial fibrillation locus. When deleted in the mouse germline, Pitx2 haploinsufficiency predisposes to pacing induced atrial fibrillation indicating that reduced Pitx2 promotes an arrhythmogenic substrate. Previous work focused on Pitx2 developmental functions that predispose to atrial fibrillation. Although Pitx2 is expressed in postnatal left atrium, it is unknown whether Pitx2 has distinct postnatal and developmental functions. Methods and Results To investigate Pitx2 postnatal function, we conditionally inactivated Pitx2 in the postnatal atrium while leaving its developmental function intact. Unstressed adult Pitx2 homozygous mutant mice display variable R-R interval with diminished P-wave amplitude characteristic of sinus node dysfunction, an atrial fibrillation risk factor in human patients. An integrated genomics approach in the adult heart revealed Pitx2 target genes encoding cell junction proteins, ion channels, and critical transcriptional regulators. Importantly, many Pitx2 target genes have been implicated in human atrial fibrillation by genome wide association studies. Immunofluorescence and transmission electron microscopy studies in adult Pitx2 mutant mice revealed structural remodeling of the intercalated disc characteristic of human atrial fibrillation patients. Conclusions Our findings, revealing that Pitx2 has genetically separable postnatal and developmental functions, unveil direct Pitx2 target genes that include channel and calcium handling genes as well as genes that stabilize the intercalated disc in postnatal atrium. PMID:24395921

  3. Prediction of atrial fibrillation development and progression: Current perspectives

    PubMed Central

    Vlachos, Konstantinos; Letsas, Konstantinos P; Korantzopoulos, Panagiotis; Liu, Tong; Georgopoulos, Stamatis; Bakalakos, Athanasios; Karamichalakis, Nikolaos; Xydonas, Sotirios; Efremidis, Michael; Sideris, Antonios

    2016-01-01

    Atrial fibrillation (AF) is the most common arrhythmia in clinical practice. Several conventional and novel predictors of AF development and progression (from paroxysmal to persistent and permanent types) have been reported. The most important predictor of AF progression is possibly the arrhythmia itself. The electrical, mechanical and structural remodeling determines the perpetuation of AF and the progression from paroxysmal to persistent and permanent forms. Common clinical scores such as the hypertension, age ≥ 75 years, transient ischemic attack or stroke, chronic obstructive pulmonary disease, and heart failure and the congestive heart failure, hypertension, age ≥ 75 years, diabetes mellitus, stroke/transient ischemic attack, vascular disease, age 65-74 years, sex category scores as well as biomarkers related to inflammation may also add important information on this topic. There is now increasing evidence that even in patients with so-called lone or idiopathic AF, the arrhythmia is the manifestation of a structural atrial disease which has recently been defined and described as fibrotic atrial cardiomyopathy. Fibrosis results from a broad range of factors related to AF inducing pathologies such as cell stretch, neurohumoral activation, and oxidative stress. The extent of fibrosis as detected either by late gadolinium enhancement-magnetic resonance imaging or electroanatomic voltage mapping may guide the therapeutic approach based on the arrhythmia substrate. The knowledge of these risk factors may not only delay arrhythmia progression, but also reduce the arrhythmia burden in patients with first detected AF. The present review highlights on the conventional and novel risk factors of development and progression of AF. PMID:27022458

  4. Improvements in atrial fibrillation detection for real-time monitoring.

    PubMed

    Babaeizadeh, Saeed; Gregg, Richard E; Helfenbein, Eric D; Lindauer, James M; Zhou, Sophia H

    2009-01-01

    Electrocardiographic (ECG) monitoring plays an important role in the management of patients with atrial fibrillation (AF). Automated real-time AF detection algorithm is an integral part of ECG monitoring during AF therapy. Before and after antiarrhythmic drug therapy and surgical procedures require ECG monitoring to ensure the success of AF therapy. This article reports our experience in developing a real-time AF monitoring algorithm and techniques to eliminate false-positive AF alarms. We start by designing an algorithm based on R-R intervals. This algorithm uses a Markov modeling approach to calculate an R-R Markov score. This score reflects the relative likelihood of observing a sequence of R-R intervals in AF episodes versus making the same observation outside AF episodes. Enhancement of the AF algorithm is achieved by adding atrial activity analysis. P-R interval variability and a P wave morphology similarity measure are used in addition to R-R Markov score in classification. A hysteresis counter is applied to eliminate short AF segments to reduce false AF alarms for better suitability in a monitoring environment. A large ambulatory Holter database (n = 633) was used for algorithm development and the publicly available MIT-BIH AF database (n = 23) was used for algorithm validation. This validation database allowed us to compare our algorithm performance with previously published algorithms. Although R-R irregularity is the main characteristic and strongest discriminator of AF rhythm, by adding atrial activity analysis and techniques to eliminate very short AF episodes, we have achieved 92% sensitivity and 97% positive predictive value in detecting AF episodes, and 93% sensitivity and 98% positive predictive value in quantifying AF segment duration. PMID:19608194

  5. Phase synchrony reveals organization in human atrial fibrillation.

    PubMed

    Vidmar, David; Narayan, Sanjiv M; Rappel, Wouter-Jan

    2015-12-15

    It remains unclear if human atrial fibrillation (AF) is spatially nonhierarchical or exhibits a hierarchy of organization sustained by sources. We utilize activation times obtained at discrete locations during AF to compute the phase synchrony between tissue regions, to examine underlying spatial dynamics throughout both atria. We construct a binary synchronization network and show that this network can accurately define regions of coherence in coarse-grained in silico data. Specifically, domains controlled by spiral waves exhibit regions of high phase synchrony. We then apply this analysis to clinical data from patients experiencing cardiac arrhythmias using multielectrode catheters to simultaneously record from a majority of both atria. We show that pharmaceutical intervention with ibutilide organizes activation by increasing the size of the synchronized domain in AF and quantify the increase in temporal organization when arrhythmia changes from fibrillation to tachycardia. Finally, in recordings from 24 patients in AF we show that the level of synchrony is spatially broad with some patients showing large spatially contiguous regions of synchronization, while in others synchrony is localized to small pockets. Using computer simulations, we show that this distribution is inconsistent with distributions obtained from simulations that mimic multiwavelet reentry but is consistent with mechanisms in which one or more spatially conserved spiral waves is surrounded by tissue in which activation is disorganized. PMID:26475585

  6. Digoxin: A systematic review in atrial fibrillation, congestive heart failure and post myocardial infarction

    PubMed Central

    Virgadamo, Sebastiano; Charnigo, Richard; Darrat, Yousef; Morales, Gustavo; Elayi, Claude S

    2015-01-01

    AIM: To review digoxin use in systolic congestive heart failure, atrial fibrillation, and after myocardial infarction. METHODS: A comprehensive PubMed search was performed using the key words “digoxin and congestive heart failure”, “digoxin and atrial fibrillation”, “digoxin, atrial fibrillation and systolic congestive heart failure”, and “digoxin and myocardial infarction”. Only articles written in English were included in this study. We retained studies originating from randomized controlled trials, registries and included at least 500 patients. The studies included patients with atrial fibrillation or heart failure or myocardial infarction and had a significant proportion of patients (at least 5%) on digoxin. A table reviewing the different hazard ratios was developed based on the articles selected. Our primary endpoint was the overall mortality in the patients on digoxin vs those without digoxin, among patients with atrial fibrillation and also among patients with atrial fibrillation and systolic heart failure. We reviewed the most recent international guidelines to discuss current recommendations. RESULTS: A total of 18 studies were found that evaluated digoxin and overall mortality in different clinical settings including systolic congestive heart failure and normal sinus rhythm (n = 5), atrial fibrillation with and without systolic congestive heart failure (n = 9), and myocardial infarction (n = 4). Overall, patients with systolic congestive heart failure with normal sinus rhythm, digoxin appears to have a neutral effect on mortality especially if close digoxin level monitoring is employed. However, most of the observational studies evaluating digoxin use in atrial fibrillation without systolic congestive heart failure showed an increase in overall mortality when taking digoxin. In the studies evaluated in this systematic review, the data among patients with atrial fibrillation and systolic congestive heart failure, as well as post myocardial

  7. [In recurrent atrial fibrillation should a sinus rhythm always try to be maintained? How?].

    PubMed

    de Sousa, J

    1999-10-01

    This paper presents the therapeutic options for recurrent paroxysmal atrial fibrillation. In the majority of patients, sinus rhythm should be maintained in order to improve cardiac function and decrease the risk of systemic embolism. Therapeutic options include serial pharmacological agents (with repeated external cardioversion) or non-pharmacological therapy: catheter or surgical ablation and atrial pacing.

  8. Minimally Invasive Repair of Mitral Valve Prolapse and Concomitant Atrial Fibrillation Ablation in a Heart Transplant.

    PubMed

    Martens, Thomas; Caes, Frank; De Pauw, Michel; Hens, Lineke; Bove, Thierry

    2016-10-01

    Significant mitral valve disease with atrial fibrillation after heart transplantation is unusual. We report the diagnosis and minimally invasive surgical treatment 17 years after transplantation, in which mitral valve repair together with left atrial ablation was performed, resulting in a satisfying clinical and echocardiographic improvement. PMID:27645968

  9. 77 FR 11121 - Scientific Information Request on Treatment of Atrial Fibrillation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-24

    ... HUMAN SERVICES Agency for Healthcare Research and Quality Scientific Information Request on Treatment of... information is being solicited to inform our Comparative Effectiveness Review of the Treatment of Atrial... effectiveness review of the evidence for the treatment of atrial fibrillation. The EHC Program is dedicated...

  10. Dual-chamber implantable cardioverter-defibrillator. Is it useful in patient with permanent atrial fibrillation?

    PubMed

    Porres-Aracama, José M; Cerezuela, José Luis; García-Urra, Francisco; Luque-Lezcano, Oscar; Herrero, Vicente

    2016-08-01

    In patients with permanent atrial fibrillation (AF) and implantable cardioverter-defibrillator (ICD) implant indication, a single-chamber device is the choice because AF does not provide interesting information for the treatment. It is very unusual to find patients with permanent AF that coexist with atrial tachycardia with various degree of Atrioventricular block. PMID:27525075

  11. A left atrial ablation with bipolar irrigated radio-frequency for atrial fibrillation during minimally invasive mitral valve surgery.

    PubMed

    Solinas, Marco; Bevilacqua, Stefano; Karimov, Jamshid H; Glauber, Mattia

    2010-04-01

    Minimally invasive mitral valve surgery is becoming increasingly popular worldwide. Mitral valve disease is often associated with atrial fibrillation (AF), also due to the ageing of the population. We present a technique to perform a left atrial ablation with bipolar irrigated radio-frequency (RF) through a single right thoracotomy. We have operated on eight patients: six female with a mean age 68+/-8 years. Six patients suffered from permanent AF and other two from paroxysmal AF. PMID:19942447

  12. A porcine model of early atrial fibrillation using a custom-built, radio transmission-controlled pacemaker.

    PubMed

    Schwarzl, Michael; Alogna, Alessio; Zweiker, David; Verderber, Jochen; Huber, Stefan; Manninger, Martin; Scherr, Daniel; Antoons, Gudrun; Pieske, Burkert M; Post, Heiner; Lueger, Andreas

    2016-01-01

    Mechanisms underlying atrial remodeling toward atrial fibrillation (AF) are incompletely understood. We induced AF in 16 pigs by 6weeks of rapid atrial pacing (RAP, 600bpm) using a custom-built, telemetrically controlled pacemaker. AF evolution was monitored three times per week telemetrically in unstressed, conscious animals. We established a dose-response relationship between RAP duration and occurrence of sustained AF >60minutes. Left atrial (LA) dilatation was present already at 2weeks of RAP. There was no evidence of left ventricular heart failure after 6weeks of RAP. As a proof-of-principle, arterial hypertension was induced in 5/16 animals by implanting desoxycorticosterone acetate (DOCA, an aldosterone-analog) subcutaneously to accelerate atrial remodeling. RAP+DOCA resulted in increased AF stability with earlier onset of sustained AF and accelerated anatomical atrial remodeling with more pronounced LA dilatation. This novel porcine model can serve to characterize effects of maladaptive stimuli or protective interventions specifically during early AF. PMID:26803554

  13. Compromised redox homeostasis, altered nitroso–redox balance, and therapeutic possibilities in atrial fibrillation

    PubMed Central

    Simon, Jillian N.; Ziberna, Klemen; Casadei, Barbara

    2016-01-01

    Although the initiation, development, and maintenance of atrial fibrillation (AF) have been linked to alterations in myocyte redox state, the field lacks a complete understanding of the impact these changes may have on cellular signalling, atrial electrophysiology, and disease progression. Recent studies demonstrate spatiotemporal changes in reactive oxygen species production shortly after the induction of AF in animal models with an uncoupling of nitric oxide synthase activity ensuing in the presence of long-standing persistent AF, ultimately leading to a major shift in nitroso–redox balance. However, it remains unclear which radical or non-radical species are primarily involved in the underlying mechanisms of AF or which proteins are targeted for redox modification. In most instances, only free radical oxygen species have been assessed; yet evidence from the redox signalling field suggests that non-radical species are more likely to regulate cellular processes. A wider appreciation for the distinction of these species and how both species may be involved in the development and maintenance of AF could impact treatment strategies. In this review, we summarize how redox second-messenger systems are regulated and discuss the recent evidence for alterations in redox regulation in the atrial myocardium in the presence of AF, while identifying some critical missing links. We also examine studies looking at antioxidants for the prevention and treatment of AF and propose alternative redox targets that may serve as superior therapeutic options for the treatment of AF. PMID:26786158

  14. Compromised redox homeostasis, altered nitroso-redox balance, and therapeutic possibilities in atrial fibrillation.

    PubMed

    Simon, Jillian N; Ziberna, Klemen; Casadei, Barbara

    2016-04-01

    Although the initiation, development, and maintenance of atrial fibrillation (AF) have been linked to alterations in myocyte redox state, the field lacks a complete understanding of the impact these changes may have on cellular signalling, atrial electrophysiology, and disease progression. Recent studies demonstrate spatiotemporal changes in reactive oxygen species production shortly after the induction of AF in animal models with an uncoupling of nitric oxide synthase activity ensuing in the presence of long-standing persistent AF, ultimately leading to a major shift in nitroso-redox balance. However, it remains unclear which radical or non-radical species are primarily involved in the underlying mechanisms of AF or which proteins are targeted for redox modification. In most instances, only free radical oxygen species have been assessed; yet evidence from the redox signalling field suggests that non-radical species are more likely to regulate cellular processes. A wider appreciation for the distinction of these species and how both species may be involved in the development and maintenance of AF could impact treatment strategies. In this review, we summarize how redox second-messenger systems are regulated and discuss the recent evidence for alterations in redox regulation in the atrial myocardium in the presence of AF, while identifying some critical missing links. We also examine studies looking at antioxidants for the prevention and treatment of AF and propose alternative redox targets that may serve as superior therapeutic options for the treatment of AF.

  15. The diagnostic accuracy of the MyDiagnostick to detect atrial fibrillation in primary care

    PubMed Central

    2014-01-01

    Background Atrial fibrillation is very common in people aged 65 or older. This condition increases the risk of death, congestive heart failure and thromboembolic conditions. Many patients with atrial fibrillation are asymptomatic and a cerebrovascular accident (CVA) is often the first clinical presentation. Guidelines concerning the prevention of CVA recommend monitoring the heart rate in patients aged 65 or older. Recently, the MyDiagnostick (Applied Biomedical Systems BV, Maastricht, The Netherlands) was introduced as a new screening tool which might serve as an alternative for the less accurate pulse palpation. This study was designed to explore the diagnostic accuracy of the MyDiagnostick for the detection of atrial fibrillation. Methods A phase II diagnostic accuracy study in a convenience sample of 191 subjects recruited in primary care. The majority of participants were patients with a known history of atrial fibrillation (n = 161). Readings of the MyDiagnostick were compared with electrocardiographic recordings. Sensitivity and specificity and their 95% confidence interval were calculated using 2x2 tables. Results A prevalence of 54% for an atrial fibrillation rhythm was found in the study population at the moment of the study. A combination of three measurements with the MyDiagnostick for each patient showed a sensitivity of 94% (95% CI 87 – 98) and a specificity of 93% (95% CI 85 – 97). Conclusion The MyDiagnostick is an easy-to-use device that showed a good diagnostic accuracy with a high sensitivity and specificity for atrial fibrillation in a convenience sample in primary care. Future research is needed to determine the place of the MyDiagnostick in possible screening or case-finding strategies for atrial fibrillation. PMID:24913608

  16. Automated Detection of Atrial Fibrillation from the Electrocardiogram Channel of Polysomnograms

    PubMed Central

    Monahan, Ken; Song, Yanna; Loparo, Ken; Mehra, Reena; Harrell, Frank E; Redline, Susan

    2016-01-01

    Purpose Accurate identification of atrial fibrillation episodes from polysomnograms is important for research purposes, but requires manual review of a large number of long electrocardiographic tracings. As automated assessment of these tracings for atrial fibrillation may improve efficiency, this study aimed to evaluate this approach in polysomnogram-derived electrocardiographic data. Methods A previously described algorithm to detect atrial fibrillation from single-lead electrocardiograms was applied to polysomnograms from a large epidemiologic study of obstructive sleep apnea in older men (Osteoporotic Fractures in Men [MrOS] Sleep Study). Atrial fibrillation status during each participant's PSG was determined by independent manual review. Models to predict atrial fibrillation status from a combination of algorithm output and clinical/polysomnographic characteristics were developed and their accuracy was evaluated using standard statistical techniques. Results Derivation and validation cohorts each consisted of 1395 individuals; 5% of each group had atrial fibrillation. Model parameters were optimized for the derivation cohort using the Akaike Information Criterion. Application to the validation cohort of these optimized models revealed high sensitivity (85-90%) and specificity (90-95%) as well as good predictive ability, as assessed by the C statistic (> 0.9) and generalized R2 values (∼ 0.6). Addition of cardiovascular or polysomnogram data to the models did not improve their performance. Conclusions In a research setting, automated detection of atrial fibrillation from polysomnogram-derived electrocardiographic signals appears feasible and agrees well with manual identification. Future studies can evaluate the utility of this technique as applied to clinical polysomnograms and ambulatory electrocardiographic monitoring. PMID:26092280

  17. Long-term risk of atrial fibrillation after the death of a partner

    PubMed Central

    Graff, Simon; Fenger-Grøn, Morten; Christensen, Bo; Pedersen, Henrik Søndergaard; Christensen, Jakob; Li, Jiong; Vestergaard, Mogens

    2016-01-01

    Objectives Severe psychological stress is generally associated with an increased risk of acute cardiovascular diseases, such as myocardial infarction, but it remains unknown whether it also applies to atrial fibrillation. We conducted a population-based case–control study using nationwide Danish health registers to examine the risk of atrial fibrillation after the death of a partner. Methods From 1995 through 2014, we identified 88 612 cases with a hospital diagnosis of atrial fibrillation and 886 120 age-matched and sex-matched controls based on risk-set sampling. The conditional logistic regression model was used to calculate adjusted ORs of atrial fibrillation with 95% CIs. Results Partner bereavement was experienced by 17 478 cases and 168 940 controls and was associated with a transiently higher risk of atrial fibrillation; the risk was highest 8–14 days after the loss (1.90; 95% CI 1.34 to 2.69), after which it gradually declined. One year after the loss, the risk was almost the same as in the non-bereaved population. Overall, the OR of atrial fibrillation within 30 days after bereavement was 1.41 (95% CI 1.17 to 1.70), but it tended to be higher in persons below the age of 60 years (2.34; 95% CI 1.02 to 5.40) and in persons whose partner had a low predicted mortality 1 month before the death, that is, ≤5 points on the age-adjusted Charlson Comorbidity Index (1.57; 95% CI 1.13 to 2.17). Conclusions The severely stressful life event of losing a partner was followed by a transiently increased risk of atrial fibrillation lasting for 1 year, especially for the least predicted losses. PMID:27099762

  18. The QT Interval and Risk of Incident Atrial Fibrillation

    PubMed Central

    Mandyam, Mala C.; Soliman, Elsayed Z.; Alonso, Alvaro; Dewland, Thomas A.; Heckbert, Susan R.; Vittinghoff, Eric; Cummings, Steven R.; Ellinor, Patrick T.; Chaitman, Bernard R.; Stocke, Karen; Applegate, William B.; Arking, Dan E.; Butler, Javed; Loehr, Laura R.; Magnani, Jared W.; Murphy, Rachel A.; Satterfield, Suzanne; Newman, Anne B.; Marcus, Gregory M.

    2013-01-01

    BACKGROUND Abnormal atrial repolarization is important in the development of atrial fibrillation (AF), but no direct measurement is available in clinical medicine. OBJECTIVE To determine whether the QT interval, a marker of ventricular repolarization, could be used to predict incident AF. METHODS We examined a prolonged QT corrected by the Framingham formula (QTFram) as a predictor of incident AF in the Atherosclerosis Risk in Communities (ARIC) study. The Cardiovascular Health Study (CHS) and Health, Aging, and Body Composition (Health ABC) study were used for validation. Secondary predictors included QT duration as a continuous variable, a short QT interval, and QT intervals corrected by other formulae. RESULTS Among 14,538 ARIC participants, a prolonged QTFram predicted a roughly two-fold increased risk of AF (hazard ratio [HR] 2.05, 95% confidence interval [CI] 1.42–2.96, p<0.001). No substantive attenuation was observed after adjustment for age, race, sex, study center, body mass index, hypertension, diabetes, coronary disease, and heart failure. The findings were validated in CHS and Health ABC and were similar across various QT correction methods. Also in ARIC, each 10-ms increase in QTFram was associated with an increased unadjusted (HR 1.14, 95%CI 1.10–1.17, p<0.001) and adjusted (HR 1.11, 95%CI 1.07–1.14, p<0.001) risk of AF. Findings regarding a short QT were inconsistent across cohorts. CONCLUSIONS A prolonged QT interval is associated with an increased risk of incident AF. PMID:23872693

  19. Galectin 3 and incident atrial fibrillation in the community

    PubMed Central

    Ho, Jennifer E.; Yin, Xiaoyan; Levy, Daniel; Vasan, Ramachandran S.; Magnani, Jared W.; Ellinor, Patrick T.; McManus, David D.; Lubitz, Steven A.; Larson, Martin G.; Benjamin, Emelia J.

    2014-01-01

    Background Galectin 3 (Gal-3) is a potential mediator of cardiac fibrosis, and Gal-3 concentrations predict incident heart failure. The same mechanisms that lead to cardiac fibrosis in heart failure may influence development of atrial fibrosis and atrial fibrillation (AF). We examined the association of Gal-3 and incident AF in the community. Methods Plasma Gal-3 concentrations were measured in 3,306 participants of the Framingham Offspring cohort who attended the sixth examination cycle (1995–1998, mean age 58 years, 54% women). Cox proportional hazards regression models were used to assess the association of baseline Gal-3 concentrations and incident AF. Results Over a median follow-up period of 10 years, 250 participants developed incident AF. Crude incidence rates of AF by increasing sex-specific Gal-3 quartiles were 3.7%, 5.9%, 9.1%, and 11.5% (log-rank test P < .0001). In age- and sex-adjusted analyses, each 1-SD increase in loge-Gal-3 was associated with a 19% increased hazard of incident AF (hazard ratio 1.19, 95% CI 1.05–1.36, P = .009). This association was not significant after adjustment for traditional clinical AF risk factors (hazard ratio 1.12, 95% CI 0.98–1.28, P = .10). Conclusion Higher circulating Gal-3 concentrations were associated with increased risk of developing AF over the subsequent 10 years in age- and sex-adjusted analyses but not after accounting for other traditional clinical AF risk factors. Our results do not support a role for Gal-3 in AF risk prediction. Further studies are needed to evaluate whether Gal-3 plays a role in the development of AF substrate similar to HF. PMID:24766984

  20. Paroxysmal atrial fibrillation prediction method with shorter HRV sequences.

    PubMed

    Boon, K H; Khalil-Hani, M; Malarvili, M B; Sia, C W

    2016-10-01

    This paper proposes a method that predicts the onset of paroxysmal atrial fibrillation (PAF), using heart rate variability (HRV) segments that are shorter than those applied in existing methods, while maintaining good prediction accuracy. PAF is a common cardiac arrhythmia that increases the health risk of a patient, and the development of an accurate predictor of the onset of PAF is clinical important because it increases the possibility to stabilize (electrically) and prevent the onset of atrial arrhythmias with different pacing techniques. We investigate the effect of HRV features extracted from different lengths of HRV segments prior to PAF onset with the proposed PAF prediction method. The pre-processing stage of the predictor includes QRS detection, HRV quantification and ectopic beat correction. Time-domain, frequency-domain, non-linear and bispectrum features are then extracted from the quantified HRV. In the feature selection, the HRV feature set and classifier parameters are optimized simultaneously using an optimization procedure based on genetic algorithm (GA). Both full feature set and statistically significant feature subset are optimized by GA respectively. For the statistically significant feature subset, Mann-Whitney U test is used to filter non-statistical significance features that cannot pass the statistical test at 20% significant level. The final stage of our predictor is the classifier that is based on support vector machine (SVM). A 10-fold cross-validation is applied in performance evaluation, and the proposed method achieves 79.3% prediction accuracy using 15-minutes HRV segment. This accuracy is comparable to that achieved by existing methods that use 30-minutes HRV segments, most of which achieves accuracy of around 80%. More importantly, our method significantly outperforms those that applied segments shorter than 30 minutes. PMID:27480743

  1. Quality of life variables in the selection of rate versus rhythm control in patients with atrial fibrillation: observations from the Canadian Trial of Atrial Fibrillation.

    PubMed

    Dorian, Paul; Mangat, Iqwal

    2003-09-01

    Many patients with atrial fibrillation develop symptoms attributable to the cardiac arrhythmia itself. These symptoms may be improved either by restoring sinus rhythm or by controlling the rapid and irregular ventricular response that often accompanies this arrhythmia. One of the principal goals of therapy of atrial fibrillation management is improvement of patient symptoms; it is important to quantify these symptoms by some form of quality of life analysis. The Canadian Trial of Atrial Fibrillation (CTAF) was a multi-centre randomized clinical trial of amiodarone compared with either propafenone or sotalol in patients with recent atrial fibrillation. The quality of life (QOL) substudy of CTAF was a prospective, comprehensive assessment of quality of life of patients enrolled in CTAF. Summary measures of physical and mental health on the generic QOL scale (SF-36) improved significantly with treatment from baseline to 3 months (41.9 +/- 9.6 to 43.7 +/- 9.2, p = 0.001 for the physical component and 47.5 +/- 10.4 to 49.0 +/- 9.8, p = 0.023 for the mental component). On an arrhythmia specific scale (SCL), a significant and larger improvement was noted from baseline to 3 months in both arrhythmia symptom frequency and severity (symptom frequency from 20.4 +/- 9.4 to 16.2 +/- 9.5, symptom severity from 16.7 +/- 8.2 to 12.9 +/- 7.6, both p < 0.001). The quality of life improvements were similar in the amiodarone group compared to the sotalol or propafenone groups, both for the SF-36 and the disease-specific symptom checklist (SCL) measures. In contrast, an atrial fibrillation severity scale (AFSS) did show differences between the assigned drug therapies, which were associated with different rates of arrhythmia recurrence in the parent study. By 3 months global well-being was significantly worse for patients who had recurrent atrial fibrillation compared to those who did not (6.9 +/- 1.8 versus 7.4 +/- 1.8, p = 0.04). Similarly, symptom severity at 3 months was 11.8 +/- 7

  2. Effect of β-Blockers on the Risk of Atrial Fibrillation in Patients with Acute Myocardial Infarction

    PubMed Central

    Pesaro, Antonio Eduardo; de Matos Soeiro, Alexandre; Serrano, Carlos Vicente; Giraldez, Roberto Rocha; Ladeira, Renata Teixeira; Nicolau, José Carlos

    2010-01-01

    INTRODUCTION: Oral β-blockers improve the prognosis of patients with acute myocardial infarction, while atrial fibrillation worsens the prognosis of this population. The reduction of atrial fibrillation incidence in patients treated with β-blockers could at least in part explain the benefits of this drug. OBJECTIVE: To investigate the effect of β-blockers on the incidence of atrial fibrillation in patients with acute myocardial infarction. METHODS: We analyzed 1401 patients with acute myocardial infarction and evaluated the occurrence or absence of atrial fibrillation, the use of oral β-blockers and mortality during the first 24 hours. RESULTS: a) The use of β-blockers was inversely correlated with the presence of atrial fibrillation (ρ = 0.004; OR = 0.54). b) Correlations with mortality were as follows: 31.5% in patients with atrial fibrillation, 9.2% in those without atrial fibrillation (ρ < 0.001; Odds Ratio = 4.52), and 17.5% in patients not treated with β-blockers and 6.7% in those who received the drug (ρ < 0.001; OR = 0.34). c) Adjusted Models: The presence of atrial fibrillation was independently correlated with mortality (OR = 2.48, ρ = 0.002). The use of β-blockers was inversely and independently correlated with mortality (OR = 0.53; ρ = 0.002). The patients who used β-blockers showed a lower risk of atrial fibrillation (OR = 0.59; ρ = 0.029) in the adjusted model. CONCLUSION: The presence of atrial fibrillation and the absence of oral β-blockers increased in-hospital mortality in patients with acute myocardial infarction. Oral β-blockers reduced the incidence of atrial fibrillation, which might be at least partially responsible for the drug’s benefit. PMID:20360916

  3. Renal Denervation Suppresses the Inducibility of Atrial Fibrillation in a Rabbit Model for Atrial Fibrosis.

    PubMed

    Wei, Yong; Xu, Juan; Zhou, Genqing; Chen, Songwen; Ouyang, Ping; Liu, Shaowen

    2016-01-01

    Renal denervation (RD) was reported to reduce the susceptibility of atrial fibrillation (AF), but the underlying mechanism has not been well understood. This study was performed to investigate the effect of RD on the inducibility of AF in a rabbit model for atrial fibrosis and to explore the potential mechanisms. Thirty-five rabbits were randomly assigned into sham-operated group (n = 12), abdominal aortic constriction (AAC) group (n = 12) and AAC with RD (AAC-RD) group (n = 11). The incidence of AF induced by burst pacing in atriums was determined. Blood was collected to measure the levels of rennin, angiotensin II and aldosterone. Atrial samples were preserved to evaluate protein and gene expression of collagen, connective tissue growth factor (CTGF) and transforming growth factor-β1 (TGF-β1). Our data suggested cardiac structure remodeling and atrial fibrosis were successfully induced by AAC. Compared with the AAC group, the AAC-RD rabbits had smaller ascending aortic diameter and left ventricular end-systolic diameter. For burst pacing at the left atrium (LA), AF was induced in two of the 12 rabbits in the sham-operated group, 10 of the 12 rabbits in the AAC group, and 2 of the 11 rabbits in the AAC-RD group, with great difference among the three groups (P = 0.001). The percentage of LA burst stimulations with induced AF achieved 47.2% in the AAC group, which was higher than those in both the AAC-RD (12.1%) and the Sham-operated (5.6%) groups. Significantly increasing intercellular space in the AAC group (P<0.001) compared with the sham-operated rabbits. RD clearly decreased the volume fraction of collagen in LA and right atrium compared with that of the AAC group (P< 0.01). AAC-induced elevation of collagen I, CTGF and TGF-β1 was suppressed by RD. In conclusion, RD suppressed the inducibility of AF in a rabbit model for pressure associated atrial fibrosis, potentially by modulating renin-angiotensin-aldosterone system and decreasing pro-fibrotic factors

  4. Renal Denervation Suppresses the Inducibility of Atrial Fibrillation in a Rabbit Model for Atrial Fibrosis

    PubMed Central

    Zhou, Genqing; Chen, Songwen; Ouyang, Ping; Liu, Shaowen

    2016-01-01

    Renal denervation (RD) was reported to reduce the susceptibility of atrial fibrillation (AF), but the underlying mechanism has not been well understood. This study was performed to investigate the effect of RD on the inducibility of AF in a rabbit model for atrial fibrosis and to explore the potential mechanisms. Thirty-five rabbits were randomly assigned into sham-operated group (n = 12), abdominal aortic constriction (AAC) group (n = 12) and AAC with RD (AAC-RD) group (n = 11). The incidence of AF induced by burst pacing in atriums was determined. Blood was collected to measure the levels of rennin, angiotensin II and aldosterone. Atrial samples were preserved to evaluate protein and gene expression of collagen, connective tissue growth factor (CTGF) and transforming growth factor-β1 (TGF-β1). Our data suggested cardiac structure remodeling and atrial fibrosis were successfully induced by AAC. Compared with the AAC group, the AAC-RD rabbits had smaller ascending aortic diameter and left ventricular end-systolic diameter. For burst pacing at the left atrium (LA), AF was induced in two of the 12 rabbits in the sham-operated group, 10 of the 12 rabbits in the AAC group, and 2 of the 11 rabbits in the AAC-RD group, with great difference among the three groups (P = 0.001). The percentage of LA burst stimulations with induced AF achieved 47.2% in the AAC group, which was higher than those in both the AAC-RD (12.1%) and the Sham-operated (5.6%) groups. Significantly increasing intercellular space in the AAC group (P<0.001) compared with the sham-operated rabbits. RD clearly decreased the volume fraction of collagen in LA and right atrium compared with that of the AAC group (P< 0.01). AAC-induced elevation of collagen I, CTGF and TGF-β1 was suppressed by RD. In conclusion, RD suppressed the inducibility of AF in a rabbit model for pressure associated atrial fibrosis, potentially by modulating renin-angiotensin-aldosterone system and decreasing pro-fibrotic factors

  5. Comparing the 2010 North American and European atrial fibrillation guidelines.

    PubMed

    Gillis, Anne M; Skanes, Allan C

    2011-01-01

    This article compares the important differences in the American College of Cardiology Foundation (ACCF)/American Heart Association (AHA)/Heart Rhythm Society (HRS), Canadian Cardiovascular Society (CCS), and European Society of Cardiology (ESC) 2010 guidelines on atrial fibrillation (AF). All guidelines recommend more lenient targets for ventricular rate control although the CCS guidelines recommend a target heart rate at rest <100 bpm whereas the the ACCF/AHA/HRS and ESC guidelines accept a target heart rate at rest <110 bpm with provisos. All the guidelines recommend that the choice of antiarrhythmic drug for maintenance of sinus rhythm be based on the underlying cardiovascular disease state. However, the CCS guidelines do not recommend that the use of Class IC drugs or sotalol be restricted in the presence of left ventricular hypertrophy alone. All the guidelines have incorporated dronedarone into their recommendations of antiarrhythmic drug therapy for maintenance of sinus rhythm. However, the CCS guidelines do not make a specific recommendation that the use of dronedarone is reasonable to decrease the risk of hospitalization for cardiovascular causes in patients with AF. The ACCF/AHA/HRS update makes a strong recommendation for catheter ablation in patients with paroxysmal AF who have failed a single anti-arrhythmic drug whereas the CCS and ESC guidelines make this a conditional recommendation. The CCS guidelines are the only guidelines at present that recommend dabigitran for prevention of stroke in high risk patients and suggest that dabigatran is preferred to warfarin for stroke prevention in most patient groups.

  6. Measurement of ventricular function by ECG gating during atrial fibrillation

    SciTech Connect

    Bacharach, S.L.; Green, M.V.; Bonow, R.O.; Findley, S.L.; Ostrow, H.G.; Johnston, G.S.

    1981-03-01

    The assumptions necessary to perform ECG-gated cardiac studies are seemingly not valid for patients in atrial fibrillation (AF). To evaluate the effect of AF on equilibrium gated scintigraphy, beat-by-beat measurements of left-ventricular function were made on seven subjects in AF (mean heart rate 64 bpm), using a high-efficiency nonimaging detector. The parameters evaluated were ejection fraction (EF), time to end-systole (TES), peak rates of ejection and filling (PER,PFR), and their times of occurrence (TPER, TPFR). By averaging together single-beat values of EF, PER, etc., it was possible to determine the true mean values of these parameters. The single-beam mean values were compared with the corresponding parameters calculated from one ECG-gated time-activity curve (TAC) obtained by superimposing all the single-beat TACs irrespective of their length. For this population with slow heart rates, we find that the values for EF, etc., produced from ECG-gated time-activity curves, are very similar to those obtained from the single-beat data. Thus use of ECG gating at low heart rates may allow reliable estimation of average cardiac function even in subjects with AF.

  7. Atrial fibrillation in heart failure: what should we do?

    PubMed Central

    Kotecha, Dipak; Piccini, Jonathan P.

    2015-01-01

    Heart failure (HF) and atrial fibrillation (AF) are two conditions that are likely to dominate the next 50 years of cardiovascular (CV) care. Both are increasingly prevalent and associated with high morbidity, mortality, and healthcare cost. They are closely inter-related with similar risk factors and shared pathophysiology. Patients with concomitant HF and AF suffer from even worse symptoms and poorer prognosis, yet evidence-based evaluation and management of this group of patients is lacking. In this review, we evaluate the common mechanisms for the development of AF in HF patients and vice versa, focusing on the evidence for potential treatment strategies. Recent data have suggested that these patients may respond differently than those with HF or AF alone. These results highlight the clear clinical need to identify and treat according to best evidence, in order to prevent adverse outcomes and reduce the huge burden that HF and AF are expected to have on global healthcare systems in the future. We propose an easy-to-use clinical mnemonic to aid the initial management of newly discovered concomitant HF and AF, the CAN-TREAT HFrEF + AF algorithm (Cardioversion if compromised; Anticoagulation unless contraindication; Normalize fluid balance; Target initial heart rate <110 b.p.m.; Renin–angiotensin–aldosterone modification; Early consideration of rhythm control; Advanced HF therapies; Treatment of other CV disease). PMID:26419625

  8. Atrial Fibrillation and Non-cardiovascular Diseases: A Systematic Review.

    PubMed

    Ferreira, Cátia; Providência, Rui; Ferreira, Maria João; Gonçalves, Lino Manuel

    2015-11-01

    Atrial fibrillation (AF) is the most common cardiac arrhythmia and is associated with an unfavorable prognosis, increasing the risk of stroke and death. Although traditionally associated with cardiovascular diseases, there is increasing evidence of high incidence of AF in patients with highly prevalent noncardiovascular diseases, such as cancer, sepsis, chronic obstructive pulmonary disease, obstructive sleep apnea and chronic kidney disease. Therefore, considerable number of patients has been affected by these comorbidities, leading to an increased risk of adverse outcomes.The authors performed a systematic review of the literature aiming to better elucidate the interaction between these conditions.Several mechanisms seem to contribute to the concomitant presence of AF and noncardiovascular diseases. Comorbidities, advanced age, autonomic dysfunction, electrolyte disturbance and inflammation are common to these conditions and may predispose to AF.The treatment of AF in these patients represents a clinical challenge, especially in terms of antithrombotic therapy, since the scores for stratification of thromboembolic risk, such as the CHADS2 and CHA2DS2VASc scores, and the scores for hemorrhagic risk, like the HAS-BLED score have limitations when applied in these conditions.The evidence in this area is still scarce and further investigations to elucidate aspects like epidemiology, pathogenesis, prevention and treatment of AF in noncardiovascular diseases are still needed. PMID:26577719

  9. Atrial fibrillation in heart failure: what should we do?

    PubMed

    Kotecha, Dipak; Piccini, Jonathan P

    2015-12-01

    Heart failure (HF) and atrial fibrillation (AF) are two conditions that are likely to dominate the next 50 years of cardiovascular (CV) care. Both are increasingly prevalent and associated with high morbidity, mortality, and healthcare cost. They are closely inter-related with similar risk factors and shared pathophysiology. Patients with concomitant HF and AF suffer from even worse symptoms and poorer prognosis, yet evidence-based evaluation and management of this group of patients is lacking. In this review, we evaluate the common mechanisms for the development of AF in HF patients and vice versa, focusing on the evidence for potential treatment strategies. Recent data have suggested that these patients may respond differently than those with HF or AF alone. These results highlight the clear clinical need to identify and treat according to best evidence, in order to prevent adverse outcomes and reduce the huge burden that HF and AF are expected to have on global healthcare systems in the future. We propose an easy-to-use clinical mnemonic to aid the initial management of newly discovered concomitant HF and AF, the CAN-TREAT HFrEF + AF algorithm (Cardioversion if compromised; Anticoagulation unless contraindication; Normalize fluid balance; Target initial heart rate <110 b.p.m.; Renin-angiotensin-aldosterone modification; Early consideration of rhythm control; Advanced HF therapies; Treatment of other CV disease). PMID:26419625

  10. Addressing Disparities in Stroke Prevention for Atrial Fibrillation: Educational Opportunities.

    PubMed

    Karcher, Rachel; Berman, Adam E; Gross, Hartmut; Hess, David C; Jauch, Edward C; Viser, Paul E; Solenski, Nina J; Wolf, Andrew M D

    2016-07-01

    Disparities in atrial fibrillation (AF)-related stroke and mortality persist, especially racial disparities, within the US "Stroke Belt." This study identified barriers to optimal stroke prevention to develop a framework for clinician education. A comprehensive educational needs assessment was developed focusing on clinicians within the Stroke Belt. The mixed qualitative-quantitative approach included regional surveys and one-on-one clinician interviews. Identified contributors to disparities included implicit racial biases, lack of awareness of racial disparities in AF stroke risk, and lack of effective multicultural awareness and training. Additional barriers affecting disparities included patient medical mistrust and clinician-patient communication challenges. General barriers included lack of consistency in assessing stroke and anticoagulant-related bleeding risk, underuse of standardized risk assessment tools, discomfort with novel anticoagulants, and patient education deficiencies. Effective cultural competency training is one strategy to reduce disparities in AF-related stroke and mortality by improving implicit clinician bias, addressing medical mistrust, and improving clinician-patient communication. PMID:25788477

  11. Novel biomarkers in cardiology: MicroRNAs in atrial fibrillation.

    PubMed

    Orenes-Piñero, Esteban; Quintana-Giner, Miriam; Romero-Aniorte, Ana I; Valdés, Mariano; Marín, Francisco

    2015-01-01

    Atrial fibrillation (AF) is the most common sustained chronic cardiac arrhythmia in clinical practice, which increases the risk of stroke and thromboembolism and is an independent predictor of mortality. The underlying mechanisms involved in the development of AF have yet to be fully elucidated. However, once initiated, AF tends to self-perpetuate, owing to structural and electrical remodeling in the atria. MicroRNAs (miRNAs) represent a sizable sub-group of small non-coding RNAs, which degrades or inhibits the translation of their target mRNAs, thus regulating gene expression and playing an important role in a wide range of biologic processes. Clinically, there is increasing evidence of the potential diagnostic role of miRNAs as biomarkers, representing a novel therapeutic target in AF. The aim of this review is to provide an exhaustive overview of the role of miRNAs in AF and to discuss the diagnostic and therapeutic potential of miRNAs in this arrhythmia.

  12. Cost-of-illness studies of atrial fibrillation: methodological considerations.

    PubMed

    Becker, Christian

    2014-10-01

    Atrial fibrillation (AF) is the most common heart rhythm arrhythmia, which has considerable economic consequences. This study aims to identify the current cost-of-illness estimates of AF; a focus was put on describing the studies' methodology. A literature review was conducted. Twenty-eight cost-of-illness studies were identified. Cost-of-illness estimates exist for health insurance members, hospital and primary care populations. In addition, the cost of stroke in AF patients and the costs of post-operative AF were calculated. The methods used were heterogeneous, mostly studies calculated excess costs. The identified annual excess costs varied, even among studies from the USA (∼US$1900 to ∼US$19,000). While pointing toward considerable costs, the cost-of-illness studies' relevance could be improved by focusing on subpopulations and treatment mixes. As possible starting points for subsequent economic studies, the methodology of cost-of-illness studies should be taken into account using methods, allowing stakeholders to find suitable studies and validate estimates.

  13. Gender Differences of Thromboembolic Events in Atrial Fibrillation.

    PubMed

    Cheng, Emily Y; Kong, Melissa H

    2016-03-15

    Atrial fibrillation (AF) is the most common clinically relevant arrhythmia and increases the risk of thromboembolism and stroke; however, these risks are not the same for women and men. This review examines the evidence and clinical significance of increased thromboembolic risk in women with AF. The balance of results from over 30 recent studies suggests that female gender is an independent stroke risk factor in AF, and the inclusion of female gender in stroke risk stratification models, such as CHA2DS2-VASc, has improved risk assessment. Reasons for the increased thrombogenicity in women remain incompletely elucidated, but biological factors including increased hypertension, renal dysfunction, and hyperthyroidism in female patients with AF; cardiovascular remodeling; increased hypercoagulability, and estrogen hormone replacement therapy in women have been proposed. More importantly, gender differences exist in medical management of patients with AF, and compared with men, women have been found to have greater thromboembolic risk when not on anticoagulants, but may benefit from greater risk reduction when systemically anticoagulated. In conclusion, increased clinician awareness of these gender differences may help to improve the management of patients with AF. PMID:26923085

  14. Stroke Prevention in Atrial Fibrillation and Valvular Heart Disease

    PubMed Central

    Ahmad, Saad; Wilt, Heath

    2016-01-01

    There is a clinically staggering burden of disease stemming from cerebrovascular events, of which a majority are ischemic in nature and many are precipitated by atrial fibrillation (AF). AF can occur in isolation or in association with myocardial or structural heart disease. In the latter case, and when considering health at an international level, congenital and acquired valve-related diseases are frequent contributors to the current pandemic of AF and its clinical impact. Guidelines crafted by the American Heart Association, American College of Cardiology, European Society of Cardiology and Heart Rhythm Society underscore the use of vitamin K antagonists (VKAs) among patients with valvular heart disease, particularly in the presence of concomitant AF, to reduce the risk of ischemic stroke of cardioembolic origin; however, the non-VKAs, also referred to as direct, target-specific or new oral anticoagulants (NOACs), have not been actively studied in this particular population. In fact, each of the new agents is approved in patients with AF not caused by a valve problem. The aim of our review is to carefully examine the available evidence from pivotal phase 3 clinical trials of NOACs and determine how they might perform in patients with AF and concomitant valvular heart disease. PMID:27347228

  15. Elevated liver enzymes associated with dronedarone for atrial fibrillation

    PubMed Central

    2013-01-01

    A 51-year-old male with documented atrial fibrillation who was taking dronedarone 400 mg twice daily for approximately 3 months returned to the cardiologist for an ablation procedure. Baseline liver enzymes were within normal range prior to starting the medication and increased after the 3 months of therapy. Aspartate aminotransferase increased from 31 IU/L to 98 IU/L, and alanine aminotransferase increased from 21 IU/L to 101 IU/L. Two and a half months after discontinuation of the medication, liver enzymes normalized (aspartate aminotransferase: 30 IU/L and alanine aminotransferase: 25 IU/L). The Food and Drug Administration has now alerted health-care professionals of the potential for liver injury based upon post-marketing surveillance. The chronological course of elevated liver enzymes noted in our patient is suggestive of a dronedarone-induced problem. Clinicians should have a heightened awareness of the potential for liver enzyme elevation and injury with dronedarone and should monitor enzymes periodically, especially within the first 6 months of use. PMID:27489632

  16. Stroke Prevention in Atrial Fibrillation and Valvular Heart Disease.

    PubMed

    Ahmad, Saad; Wilt, Heath

    2016-01-01

    There is a clinically staggering burden of disease stemming from cerebrovascular events, of which a majority are ischemic in nature and many are precipitated by atrial fibrillation (AF). AF can occur in isolation or in association with myocardial or structural heart disease. In the latter case, and when considering health at an international level, congenital and acquired valve-related diseases are frequent contributors to the current pandemic of AF and its clinical impact. Guidelines crafted by the American Heart Association, American College of Cardiology, European Society of Cardiology and Heart Rhythm Society underscore the use of vitamin K antagonists (VKAs) among patients with valvular heart disease, particularly in the presence of concomitant AF, to reduce the risk of ischemic stroke of cardioembolic origin; however, the non-VKAs, also referred to as direct, target-specific or new oral anticoagulants (NOACs), have not been actively studied in this particular population. In fact, each of the new agents is approved in patients with AF not caused by a valve problem. The aim of our review is to carefully examine the available evidence from pivotal phase 3 clinical trials of NOACs and determine how they might perform in patients with AF and concomitant valvular heart disease. PMID:27347228

  17. Stroke prevention in atrial fibrillation: an Asian perspective.

    PubMed

    Chiang, Chern-En; Wang, Kang-Ling; Lip, Gregory Y H

    2014-05-01

    Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. In 2050, it is estimated that there will be 72 million AF patients in Asia, accounting for almost 2.9 million patients suffering from AF-associated stroke. Asian AF patients share similar risk factor profiles as non-Asians, except that more Asians have a history of previous stroke. Clinical challenges are evident in the field of stroke prevention in AF, amongst Asians. Existing stroke and bleeding risk scores have not been well-validated in Asians. Asians are prone to bleeding when treated with warfarin, and the optimal international normalised ratio (INR) for warfarin use is yet to be determined in Asians, though Asian physicians tend to keep it in a lower range (e.g. INR 1.6-2.6) for elderly patients despite limited evidence to justify this. In general, warfarin is 'difficult' to use in Asians due to higher risk of bleeding and higher stroke rate in Asians than in non-Asians, as shown in randomised controlled trials. Excess of bleeding was not found in Asians when novel oral anticoagulants (NOACs) were used. Besides, the superiority of NOACs to warfarin in reducing thromboembolism was maintained in Asians. Therefore NOACs are preferentially indicated in Asians in terms of both efficacy and safety. Also, some preliminary data suggest that Asian patients with AF might not be the same. Future prospective randomised trials are needed for the selection of NOACs according to different ethnic background.

  18. Simple Model for Identifying Critical Regions in Atrial Fibrillation

    NASA Astrophysics Data System (ADS)

    Christensen, Kim; Manani, Kishan A.; Peters, Nicholas S.

    2015-01-01

    Atrial fibrillation (AF) is the most common abnormal heart rhythm and the single biggest cause of stroke. Ablation, destroying regions of the atria, is applied largely empirically and can be curative but with a disappointing clinical success rate. We design a simple model of activation wave front propagation on an anisotropic structure mimicking the branching network of heart muscle cells. This integration of phenomenological dynamics and pertinent structure shows how AF emerges spontaneously when the transverse cell-to-cell coupling decreases, as occurs with age, beyond a threshold value. We identify critical regions responsible for the initiation and maintenance of AF, the ablation of which terminates AF. The simplicity of the model allows us to calculate analytically the risk of arrhythmia and express the threshold value of transversal cell-to-cell coupling as a function of the model parameters. This threshold value decreases with increasing refractory period by reducing the number of critical regions which can initiate and sustain microreentrant circuits. These biologically testable predictions might inform ablation therapies and arrhythmic risk assessment.

  19. Addressing Disparities in Stroke Prevention for Atrial Fibrillation: Educational Opportunities.

    PubMed

    Karcher, Rachel; Berman, Adam E; Gross, Hartmut; Hess, David C; Jauch, Edward C; Viser, Paul E; Solenski, Nina J; Wolf, Andrew M D

    2016-07-01

    Disparities in atrial fibrillation (AF)-related stroke and mortality persist, especially racial disparities, within the US "Stroke Belt." This study identified barriers to optimal stroke prevention to develop a framework for clinician education. A comprehensive educational needs assessment was developed focusing on clinicians within the Stroke Belt. The mixed qualitative-quantitative approach included regional surveys and one-on-one clinician interviews. Identified contributors to disparities included implicit racial biases, lack of awareness of racial disparities in AF stroke risk, and lack of effective multicultural awareness and training. Additional barriers affecting disparities included patient medical mistrust and clinician-patient communication challenges. General barriers included lack of consistency in assessing stroke and anticoagulant-related bleeding risk, underuse of standardized risk assessment tools, discomfort with novel anticoagulants, and patient education deficiencies. Effective cultural competency training is one strategy to reduce disparities in AF-related stroke and mortality by improving implicit clinician bias, addressing medical mistrust, and improving clinician-patient communication.

  20. Emerging Directions in the Genetics of Atrial Fibrillation

    PubMed Central

    Tucker, Nathan R.; Ellinor, Patrick T.

    2014-01-01

    Atrial fibrillation (AF) is the most common arrhythmic disorder, and currently affects nearly 3 million Americans, 8.8 million Europeans, and an estimated 30 million individuals worldwide. The clinical risk factors for AF are numerous, with age, sex, hypertension, obesity, and ischemic heart disease among the most prevalent. Over the last ten years, a preponderance of evidence also suggests a large genetic contribution to AF. The earliest report of familial AF dates to the early 1940s1. Since then, it has become apparent that AF in referral populations2,3 and in the community is heritable4,5. Indeed, having a family member with AF is associated with a 40% increased risk for the arrhythmia6. Once the heritability was recognized, traditional genetics techniques for the discovery of rare, monogenic causes of AF were used to identify the initial AF genes. These studies in turn, informed candidate gene screening in AF cohorts. To identify additional sources of heritability for AF, large-scale analyses of common variation through genome wide association studies (GWAS) has recently yielded data identifying risk loci in many regions of the genome. In spite of these advances, the combination of these techniques has, as yet, failed to completely identify the heritability of AF in the population. It is the goal of this review to examine the previous studies on rare variants, address the findings of the recent GWAS studies, and describe future avenues towards defining the heritability of AF. PMID:24763465

  1. Predictors of Atrial Fibrillation Recurrence in Hyperthyroid and Euthyroid Patients

    PubMed Central

    Gürdoğan, Muhammet; Ari, Hasan; Tenekecioğlu, Erhan; Arı, Selma; Bozat, Tahsin; Koca, Vedat; Melek, Mehmet

    2016-01-01

    Background Atrial fibrillation (AF) is the most common arrhythmia in adults, and is encountered in 10-15% of the patients with hyperthyroidism. Unless euthyroidism is restored, pharmacological or electrical cardioversion is controversial in patients with AF who remain hyperthyroid. Objective The aim of this study was to assess the efficacy of electrical cardioversion and predictors of AF recurrence in hyperthyroid and euthyroid patients. Methods The study included 33 hyperthyroid (21 males) and 48 euthyroid (17 males) patients with persistent AF. The patients were sedated with intravenous midazolam before undergoing electrical cardioversion delivered by synchronized biphasic shocks. Rates of AF recurrence were recorded. Results Mean follow-up was 23.63 ± 3.74 months in the hyperthyroid group and 22.78 ± 3.15 months in the euthyroid group (p = 0.51). AF recurred in 14 (43.8%) and 21 (44.7%) patients in each group, respectively (p = 0.93). Multivariate regression analysis in each group showed that AF duration was the only predictor of AF recurrence, with odds ratios of 1.38 (95% confidence interval [CI] = 1.05 - 1.82, p = 0.02) in the hyperthyroid group and 1.42 (95% CI = 1.05 - 1.91, p= 0.02) in the euthyroid group. Conclusion Rates of long-term AF recurrence were similar in successfully cardioverted hyperthyroid and euthyroid patients. The only predictor of AF recurrence in both groups was AF duration. PMID:26815460

  2. The changing circumstance of atrial fibrillation - progress towards precision medicine.

    PubMed

    Camm, A J; Savelieva, I; Potpara, T; Hindriks, G; Pison, L; Blömstrom-Lundqvist, C

    2016-05-01

    The prevalence of atrial fibrillation (AF) in the general population is between 1% and 2% in the developed world and is higher in men than in women. The arrhythmia occurs much more commonly in the elderly, and the estimated lifetime risk of developing AF is one in four for men and women aged 40 years and above. Projected data from multiple population-based studies in the USA and Europe predict a two- to threefold increase in the number of AF patients by 2060. The high lifetime risk of AF and increased longevity underscore the important public health burden posed by this arrhythmia worldwide. AF has multiple aetiologies and a broad variety of presentations. The primary pathologies underlying or promoting the occurrence of AF vary more than for any other cardiac arrhythmia, ranging from autonomic imbalance to organic heart disease and metabolic disorders, such as diabetes mellitus, metabolic syndrome, hyperthyroidism and kidney disease, and lifestyle factors such as smoking, alcohol consumption and participation in endurance sports. Biomarkers are increasingly being investigated and, together with clinical and genetic factors, will eventually lead to a clinically valuable detailed classification of AF which will also incorporate pathophysiological determinants and mechanisms of the arrhythmia. In turn, this will allow the development and application of precision medicine to this troublesome arrhythmia.

  3. An unusual complication of atrial fibrillation ablation: case report.

    PubMed

    Petrela, Mentor; Rroji, Arben; Enesi, Eugen; Xhumari, Artur; Lame, Artid

    2015-12-01

    The authors report a complication of catheter ablation that, to their knowledge, has never been previously reported. A 63-year-old man had undergone successful transvenous catheter thermoablation for atrial fibrillation. The patient remained well until 3 days prior to further admission when he noticed itching in the right frontal area of his scalp. On palpating his scalp, he discovered a metallic body projecting out of it and he proceeded to extract 20 cm of wire from his head. The following day a progressive left hemiplegia developed, and the patient experienced a deteriorating level of consciousness. A CT scan of the brain showed a right frontotemporal intraparenchymal hemorrhage and revealed a metallic structure in the middle of the hematoma. The hematoma was evacuated and a decompressive craniotomy was performed. The guidewire was identified, but it was only possible to extract part of it. It was covered by fibrous tissue, secondary to inflammatory reaction. To the authors' knowledge, this is the first report of guidewire-induced brain hemorrhage. The guidewire apparently had not been removed and had spontaneously migrated from the heart to the brain and beyond to the scalp where it then exited the patient's head. The patient had been well before he attempted to pull out the wire. Earlier identification of the iatrogenic complication of a retained guidewire might have prevented the fatal outcome in this case. PMID:26047416

  4. The changing circumstance of atrial fibrillation - progress towards precision medicine.

    PubMed

    Camm, A J; Savelieva, I; Potpara, T; Hindriks, G; Pison, L; Blömstrom-Lundqvist, C

    2016-05-01

    The prevalence of atrial fibrillation (AF) in the general population is between 1% and 2% in the developed world and is higher in men than in women. The arrhythmia occurs much more commonly in the elderly, and the estimated lifetime risk of developing AF is one in four for men and women aged 40 years and above. Projected data from multiple population-based studies in the USA and Europe predict a two- to threefold increase in the number of AF patients by 2060. The high lifetime risk of AF and increased longevity underscore the important public health burden posed by this arrhythmia worldwide. AF has multiple aetiologies and a broad variety of presentations. The primary pathologies underlying or promoting the occurrence of AF vary more than for any other cardiac arrhythmia, ranging from autonomic imbalance to organic heart disease and metabolic disorders, such as diabetes mellitus, metabolic syndrome, hyperthyroidism and kidney disease, and lifestyle factors such as smoking, alcohol consumption and participation in endurance sports. Biomarkers are increasingly being investigated and, together with clinical and genetic factors, will eventually lead to a clinically valuable detailed classification of AF which will also incorporate pathophysiological determinants and mechanisms of the arrhythmia. In turn, this will allow the development and application of precision medicine to this troublesome arrhythmia. PMID:27029018

  5. [New anticoagulants for stroke prevention in atrial fibrillation].

    PubMed

    Diener, H C; Hajjar, K; Frank, B; Perrey, M

    2012-06-01

    Oral anticoagulation with vitamin K antagonists (warfarin, phenprocoumon) is successful in both primary and secondary stroke prevention for patients with atrial fibrillation (AF), yielding a 60-70% relative reduction in stroke risk compared with placebo and a mortality reduction of 26%. However, these agents have a number of well documented shortcomings. This review describes the current landscape and developments in stroke prevention in patients with AF 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 these new agents including higher efficacy and significantly lower incidences of intracranial bleeding compared with warfarin. The new substances show similar results in secondary as well as in primary stroke prevention in patients with AF. The new anticoagulants add to the therapeutic options for patients with AF and offer a number of advantages over warfarin for both clinician and patient, including a favorable bleeding profile and convenience of use. Consideration of these new anticoagulants will improve clinical decision-making. PMID:22539096

  6. Role of neural modulation in the pathophysiology of atrial fibrillation

    PubMed Central

    Male, Shailesh; Scherlag, Benjamin J.

    2014-01-01

    Atrial-fibrillation (AF) is the most common clinically encountered arrhythmia affecting over 1 per cent of population in the United States and its prevalence seems to be moving only in forward direction. A recent systemic review estimates global prevalence of AF to be 596.2 and 373.1 per 100,000 population in males and females respectively. Multiple mechanisms have been put forward in the pathogenesis of AF, however; multiple wavelet hypothesis is the most accepted theory so far. Similar to the conduction system of the heart, a neural network exists which surrounds the heart and plays an important role in formation of the substrate of AF and when a trigger is originated, usually from pulmonary vein sleeves, AF occurs. This neural network includes ganglionated plexi (GP) located adjacent to pulmonary vein ostia which are under control of higher centers in normal people. When these GP become hyperactive owing to loss of inhibition from higher centers e.g. in elderly, AF can occur. We can control these hyperactive GP either by stimulating higher centers and their connections, e.g. vagus nerve stimulation or simply by ablating these GP. This review provides detailed information about the different proposed mechanisms underlying AF, the exact role of autonomic neural tone in the pathogenesis of AF and the possible role of neural modulation in the treatment of AF. PMID:24927337

  7. Long-term results of the corridor operation for atrial fibrillation.

    PubMed Central

    van Hemel, N. M.; Defauw, J. J.; Kingma, J. H.; Jaarsma, W.; Vermeulen, F. E.; de Bakker, J. M.; Guiraudon, G. M.

    1994-01-01

    OBJECTIVE--To investigate the long-term results of the corridor operation in the treatment of symptomatic atrial fibrillation refractory to drug treatment. BACKGROUND--The corridor operation is designed to isolate from the left and right atrium a conduit of atrial tissue connecting the sinus node area with the atrioventricular node region in order to preserve physiological ventricular drive. The excluded atria can fibrillate without affecting the ventricular rhythm. This surgical method offers an alternative treatment when atrial fibrillation becomes refractory to drug treatment. PATIENTS--From 1987 to 1993, 36 patients with drug refractory symptomatic paroxysmal atrial fibrillation underwent surgery. The in hospital rhythm was followed thereafter by continuous rhythm monitoring and with epicardial electrograms. After discharge Holter recording and stress testing were regularly carried out to evaluate the sinus node function and to detect arrhythmias; whereas Doppler echocardiography was used to measure atrial contraction and size. MAIN OUTCOME MEASURES--Maintained absence of atrial fibrillation without drug treatment after operation; preservation of normal chronotropic response in the sinus node. RESULTS--The corridor procedure was successful in 31 (86%) of the 36 patients. After a mean (SD) follow up of 41 (16) months 25 (69%) of the 36 patients were free of arrhythmias without taking drugs (mean (SE) actuarial freedom at four years 72 (9)%)). Paroxysmal atrial fibrillation recurred in three patients; paroxysmal atrial flutter (two patients) and atrial tachycardia (one patient) developed in the corridor in three others. Among the 31 patients in whom the operation was successful sinus node function at rest and during exercise remained undisturbed in 26 and 25 patients respectively (mean (SE) actuarial freedom of sinus node dysfunction at four years (81(7)%)). Pacemakers were needed in five (16%) of the 31 patients for insufficient sinus node rhythm at rest only

  8. Percutaneous left atrial appendage occlusion for stroke prevention in atrial fibrillation: an update

    PubMed Central

    De Backer, O; Arnous, S; Ihlemann, N; Vejlstrup, N; Jørgensen, E; Pehrson, S; Krieger, T D W; Meier, P; Søndergaard, L; Franzen, O W

    2014-01-01

    Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia encountered in clinical practice. One of its most devastating complications is the development of thromboembolism leading to fatal or disabling stroke. Oral anticoagulation (OAC, warfarin) is the standard treatment for stroke prevention in patients with AF with an increased stroke risk. However, there are several obstacles to long-term OAC therapy, including the risk of serious bleeding, several drug–drug interactions and the need for frequent blood testing. Although newer oral anticoagulants have been developed, these drugs also face issues of major bleeding and non-compliance. Therefore, alternative treatment options for stroke prevention in patients with AF with a high stroke risk are needed. Percutaneous left atrial appendage (LAA) occlusion is an evolving therapy, which should be taken into consideration in those patients with non-valvular AF with a high stroke risk and contraindications for OAC. This article aims to discuss the rationale for LAA closure, the available LAA occlusion devices and their clinical evidence until now. Moreover, we discuss the importance of proper patient selection, the role of various imaging techniques and the need for a more tailored postprocedural antithrombotic therapy. PMID:25332785

  9. Morbidity and treatment in patients with atrial fibrillation and chronic kidney disease.

    PubMed

    Reinecke, Holger; Nabauer, Michael; Gerth, Andrea; Limbourg, Tobias; Treszl, Andras; Engelbertz, Christiane; Eckardt, Lars; Kirchhof, Paulus; Wegscheider, Karl; Ravens, Ursula; Meinertz, Thomas; Steinbeck, Gerhard; Breithardt, Günter

    2015-01-01

    Chronic kidney disease (CKD) is associated with increased cardiovascular morbidity and mortality but there are few studies available about atrial fibrillation, the most frequent arrhythmia in CKD, and the applied treatment. Based on the prospective German Competence NETwork on Atrial Fibrillation, data of 3138 patients with atrial fibrillation were analyzed and categorized by their estimated glomerular filtration rate (stages 1-3 and 4 plus 5). With advanced CKD, significantly more patients suffered from a more severe form of atrial fibrillation. Despite significantly higher CHADS2 scores in advanced CKD, oral anticoagulation was not prescribed more frequently while antiarrhythmic drugs and catheter ablations were used significantly less often, in contrast to more pacemaker implantations. However, in multivariate hierarchical logistic regression analyses of in-hospital treatments and complications, only hemorrhages and pacemaker implantations turned out to be independently and significantly associated with higher CKD stages. This nationwide study shows that patients with CKD and atrial fibrillation suffer from a markedly higher comorbidity. Thus, while CKD patients have received cardioversions, ablations, antiarrhythmic, or anticoagulation drugs significantly less often in their history, current treatments were not different if adjusted for multiple comorbidities. This might indicate an improvement in the often reported therapeutic nihilism in CKD. PMID:24897032

  10. Health-related quality of life in atrial fibrillation patients over 65 years: A review.

    PubMed

    Zhang, Ling; Gallagher, Robyn; Neubeck, Lis

    2015-08-01

    Atrial fibrillation is the most common sustained cardiac arrhythmia affecting 1-2% of the population; the prevalence of atrial fibrillation increases with ageing. The condition is associated with high morbidity and mortality, as well as reduced health-related quality of life, particularly in older people. A PubMed, CINAHL, EMBASE and CENTRAL search (January 2003 to April 2013) was conducted using the search terms atrial fibrillation, quality of life, health-related quality of life, older, aged, and over 65 years. In total, 572 papers were identified of which 15 were eligible, including three observational studies, five descriptive comparative studies and seven randomized control trials. Older atrial fibrillation patients (≥65 years) were significantly impaired in their health-related quality of life in both physical and mental domains compared to the general population or patients with sinus rhythm. Increasing age, being female or having severe symptoms resulted in poorer health-related quality of life particularly in the physical domain. The review also found that the current treatment of AF including rate and rhythm control strategies improved some aspects of health-related quality of life in atrial fibrillation patients but no specific strategy had a superior effect.

  11. Left atrial speckle tracking analysis in patients with mitral insufficiency and history of paroxysmal atrial fibrillation.

    PubMed

    Cameli, Matteo; Lisi, Matteo; Righini, Francesca Maria; Focardi, Marta; Alfieri, Ottavio; Mondillo, Sergio

    2012-10-01

    The occurrence of atrial fibrillation (AF), especially in patients with mitral regurgitation (MR), is related to the degree of left atrial (LA) myopathy, remodeling and fibrosis, that are responsible of LA electrical inhomogeneity and abnormal conduction velocities. Speckle tracking echocardiography (STE) has recently enabled the quantification of longitudinal myocardial LA deformation dynamics. Our aim was to investigate by STE the effects of the occurrence of paroxysmal AF on LA myocardial deformation, in a population of patients with asymptomatic chronic MR. We compared two groups of a total of 197 patients with MR: 54 with history of paroxysmal AF and 143 with MR alone. Subgroups were created according to MR degree. Peak atrial longitudinal strain (PALS) was measured in all subjects. Values were obtained by averaging all segments (global PALS), measured in the 4-chamber and 2-chamber views. Compared to the mild MR group (46.1 ± 4.9%), global PALS was lower in moderate MR group (22.1 ± 5.8%) and further reduced in the severe MR group (13.9 ± 4.2%; overall P < 0.0001 by ANOVA, P < 0.05 for all pair-wise comparisons). Besides, in each MR group, patients with history of paroxysmal AF presented a global PALS significantly reduced (overall P < 0.0001 by ANOVA). After multivariate analysis, global PALS was significantly and independently associated with paroxysmal AF. STE enables noninvasive quantification of LA dysfunction due to MR and paroxysmal AF. MR have a major negative impact on LA function. In patients with MR, the history of paroxysmal AF is associated to a further impair of LA myocardial reservoir function. PMID:22130899

  12. Right Ventricular and Right Atrial Involvement Can Predict Atrial Fibrillation in Patients with Hypertrophic Cardiomyopathy?

    PubMed Central

    Doesch, Christina; Lossnitzer, Dirk; Rudic, Boris; Tueluemen, Erol; Budjan, Johannes; Haubenreisser, Holger; Henzler, Thomas; Schoenberg, Stefan O.; Borggrefe, Martin; Papavassiliu, Theano

    2016-01-01

    Objectives and Background: Atrial fibrillation (AF) is associated with clinical deterioration, stroke and disability in patients with hypertrophic cardiomyopathy (HCM). Therefore, the objective of this study was to evaluated cardiac magnetic resonance (CMR)-derived determinants for the occurrence of AF in patients with HCM. Methods: 98 Patients with HCM and 30 healthy controls underwent CMR and were followed-up for 6±3 years. Results: 19 (19.4%) patients presented with AF at initial diagnosis, 19 (19.4%) developed AF during follow-up and 60 (61.2%) remained in sinus rhythm (SR). Compared to healthy controls, patients with HCM who remained in SR presented with significantly increased left ventricular mass, an elevated left ventricular remodeling index, enlarged left atrial volumes and reduced septal mitral annular plane systolic excursion (MAPSE) compared to healthy controls. Whereas HCM patients who presented with AF at initial diagnosis and those who developed AF during follow-up additionally presented with reduced tricuspid annular plane systolic excursion (TAPSE) and right atrial (RA) dilatation. Receiver-operator curve analysis indicated good predictive performance of TAPSE, RA diameter and septal MAPSE (AUC 0.73, 0.69 and 0.71, respectively) to detect patients at risk of developing AF. Conclusion: Reduced MAPSE measurements and enlarged LA volumes seems to be a common feature in patients with HCM, whereas reduced TAPSE and RA dilatation only seem to be altered in patients with history of AF and those developing AF. Therefore, they could serve as easy determinable markers of AF in patients with HCM. PMID:26812947

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

    PubMed

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

    2016-09-01

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

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

    PubMed

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

    2016-09-01

    Catheter tissue contact force (CF) is an important factor for durable lesion formation during radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF). Since CF varies in the beating heart, atrial rhythm during RFCA may influence CF. A high-density map and RFCA points were obtained in 25 patients undergoing RFCA of AF using a CF-sensing catheter (Tacticath, St. Jude Medical). The operators were blinded to the CF information. Contact type was classified into three categories: constant, variable, and intermittent contact. Average CF and contact type were analyzed according to atrial rhythm (SR vs. AF) and anatomical location. A total of 1364 points (891 points during SR and 473 points during AF) were analyzed. Average CFs showed no significant difference between SR (17.2 ± 11.3 g) and AF (17.2 ± 13.3 g; p = 0.99). The distribution of points with an average CF of ≥20 and <10 g also showed no significant difference. However, the distribution of excessive CF (CF ≥40 g) was significantly higher during AF (7.4 %) in comparison with SR (4.2 %; p < 0.05). At the anterior area of the right inferior pulmonary vein (RIPV), the average CF during AF was significantly higher than during SR (p < 0.05). Constant contact was significantly higher during AF (32.2 %) when compared to SR (9.9 %; p < 0.01). Although the average CF was not different between atrial rhythms, constant contact was more often achievable during AF than it was during SR. However, excessive CF also seems to occur more frequently during AF especially at the anterior part of RIPV. PMID:26498938

  15. Dominant Frequency Increase Rate Predicts Transition from Paroxysmal to Long-Term Persistent Atrial Fibrillation

    PubMed Central

    Martins, Raphael P.; Kaur, Kuljeet; Hwang, Elliot; Ramirez, Rafael J.; Willis, B. Cicero; Filgueiras-Rama, David; Ennis, Steven R.; Takemoto, Yoshio; Ponce-Balbuena, Daniela; Zarzoso, Manuel; O’Connell, Ryan P.; Musa, Hassan; Guerrero-Serna, Guadalupe; Avula, Uma Mahesh R.; Swartz, Michael F.; Bhushal, Sandesh; Deo, Makarand; Pandit, Sandeep V.; Berenfeld, Omer; Jalife, José

    2014-01-01

    Background Little is known about the mechanisms underlying the transition from paroxysmal to persistent atrial fibrillation (AF). In an ovine model of long-standing persistent AF (LS-PAF) we tested the hypothesis that the rate of electrical and/or structural remodeling, assessed by dominant frequency (DF) changes, determines the time at which AF becomes persistent. Methods and Results Self-sustained AF was induced by atrial tachypacing. Seven sheep were sacrificed 11.5±2.3 days after the transition to persistent AF and without reversal to sinus rhythm (SR); 7 sheep were sacrificed after 341.3±16.7 days of LS-PAF. Seven sham-operated animals were in SR for 1 year. DF was monitored continuously in each group. RT-PCR, western blotting, patch-clamping and histological analyses were used to determine changes in functional ion channel expression and structural remodeling. Atrial dilatation, mitral valve regurgitation, myocyte hypertrophy, and atrial fibrosis occurred progressively and became statistically significant after the transition to persistent AF, with no evidence for left ventricular dysfunction. DF increased progressively during the paroxysmal-to-persistent AF transition and stabilized when AF became persistent. Importantly, the rate of DF increase (dDF/dt) correlated strongly with the time to persistent AF. Significant action potential duration (APD) abbreviation, secondary to functional ion channel protein expression changes (CaV1.2, NaV1.5 and KV4.2 decrease; Kir2.3 increase), was already present at the transition and persisted for one-year follow up. Conclusions In the sheep model of LS-PAF, the rate of DF increase predicts the time at which AF stabilizes and becomes persistent, reflecting changes in APD and densities of sodium, L-type calcium and inward rectifier currents. PMID:24463369

  16. Novel approaches for pharmacological management of atrial fibrillation.

    PubMed

    Ehrlich, Joachim R; Nattel, Stanley

    2009-01-01

    In the light of the progressively increasing prevalence of atrial fibrillation (AF), medical awareness of the need to develop improved therapeutic approaches for the arrhythmia has also risen over the last decade. AF reduces quality of life and is associated with increased morbidity and mortality. Despite several setbacks as a result of negative results from rhythm control trials, the potential advantages of sinus-rhythm (SR) maintenance have motivated continued efforts to design novel pharmacological options aiming to terminate AF and prevent its recurrence, with a hope that optimized medical therapy will improve outcomes in AF patients. Pathophysiologically, AF is associated with electrical and structural changes in the atria, which increase the propensity to arrhythmia perpetuation but may eventually allow for new modalities for therapeutic intervention. Antiarrhythmic drug therapy has traditionally targeted ionic currents that modulate excitability and/or repolarization of cardiac myocytes. Despite efficacious suppression of ventricular and supraventricular arrhythmias, traditional antiarrhythmic drugs present problematic risks of pro-arrhythmia, potentially leading to excess mortality in the case of Na+-channel blockers or IKr (IKr=the rapid component of the delayed rectifier potassium current) blockers. New anti-AF agents in development do not fit well into the classical Singh and Vaughan-Williams formulation, and are broadly divided into 'atrial-selective compounds' and 'multiple-channel blockers'. The prototypic multiple-channel blocker amiodarone is the most efficient presently available compound for SR maintenance, but the drug has extra-cardiac adverse effects and complex pharmacokinetics that limit widespread application. The other available drugs are not nearly as efficient for SR maintenance and have a greater risk of proarrhythmia than amiodarone. Two new antiarrhythmic drugs are on the cusp of introduction into clinical practice. Vernakalant affects

  17. Management and 1-year outcomes of patients with atrial fibrillation in the Middle East: Gulf survey of atrial fibrillation events.

    PubMed

    Zubaid, Mohammad; Rashed, Wafa A; Alsheikh-Ali, Alawi A; Al-Zakwani, Ibrahim; AlMahmeed, Wael; Shehab, Abdullah; Sulaiman, Kadhim; Qudaimi, Ahmed Al; Asaad, Nidal; Amin, Haitham

    2015-05-01

    We describe management and outcomes of patients with nonvalvular atrial fibrillation (AF) in the Middle East. Consecutive patients with AF presenting to emergency departments (EDs) were prospectively enrolled. Among 1721 patients with nonvalvular AF, mean age was 59 ± 16 years and 44% were women. Comorbidities were common such as hypertension (59%), diabetes (33%), and coronary artery disease (33%). Warfarin was not prescribed to 40% of patients with Congestive heart failure, Hypertension, Age, Diabetes mellitus, Stroke/TIA2 score of ≥2. One-year rates of stroke/transient ischemic attack (TIA) and all-cause mortality were 4.2% and 15.3%, respectively. Warfarin use at hospital-ED discharge was independently associated with lower 1-year rate of stroke/TIA (odds ratio [OR], 0.38; 95% confidence interval [CI], 0.17-0.85; P = .015) and all-cause mortality (OR, 0.51; 95% CI, 0.32-0.83; P = .006). Prior history of heart failure and peripheral vascular disease was independent mortality predictors. Our patients are relatively young with significant cardiovascular risk. Their anticoagulation treatment is suboptimal, and 1-year all-cause mortality and stroke/TIA event rates are relatively high.

  18. Management and 1-year outcomes of patients with atrial fibrillation in the Middle East: Gulf survey of atrial fibrillation events.

    PubMed

    Zubaid, Mohammad; Rashed, Wafa A; Alsheikh-Ali, Alawi A; Al-Zakwani, Ibrahim; AlMahmeed, Wael; Shehab, Abdullah; Sulaiman, Kadhim; Qudaimi, Ahmed Al; Asaad, Nidal; Amin, Haitham

    2015-05-01

    We describe management and outcomes of patients with nonvalvular atrial fibrillation (AF) in the Middle East. Consecutive patients with AF presenting to emergency departments (EDs) were prospectively enrolled. Among 1721 patients with nonvalvular AF, mean age was 59 ± 16 years and 44% were women. Comorbidities were common such as hypertension (59%), diabetes (33%), and coronary artery disease (33%). Warfarin was not prescribed to 40% of patients with Congestive heart failure, Hypertension, Age, Diabetes mellitus, Stroke/TIA2 score of ≥2. One-year rates of stroke/transient ischemic attack (TIA) and all-cause mortality were 4.2% and 15.3%, respectively. Warfarin use at hospital-ED discharge was independently associated with lower 1-year rate of stroke/TIA (odds ratio [OR], 0.38; 95% confidence interval [CI], 0.17-0.85; P = .015) and all-cause mortality (OR, 0.51; 95% CI, 0.32-0.83; P = .006). Prior history of heart failure and peripheral vascular disease was independent mortality predictors. Our patients are relatively young with significant cardiovascular risk. Their anticoagulation treatment is suboptimal, and 1-year all-cause mortality and stroke/TIA event rates are relatively high. PMID:24904179

  19. Left Atrial Remodeling Assessed by Transthoracic Echocardiography Predicts Left Atrial Appendage Flow Velocity in Patients With Paroxysmal Atrial Fibrillation.

    PubMed

    Watanabe, Atai; Suzuki, Shinya; Kano, Hiroto; Matsuno, Syunsuke; Takai, Hideaki; Kato, Yuko; Otsuka, Takayuki; Uejima, Tokuhisa; Oikawa, Yuji; Nagashima, Kazuyuki; Kirigaya, Hajime; Kunihara, Takashi; Sagara, Koichi; Yamashita, Naohide; Sawada, Hitoshi; Aizawa, Tadanori; Yajima, Junji; Yamashita, Takeshi

    2016-01-01

    Atrial fibrillation (AF) is associated with an increased risk of stroke and other thromboembolic events. Left atrial (LA) thrombus formation is closely related to LA dysfunction, particularly to decreased LA appendage flow velocity (LAA-FV) in patients with AF. We estimated LAA-FV using parameters noninvasively obtained by transthoracic echocardiography (TTE) in patients with paroxysmal AF.Echocardiographic and clinical parameters were assessed in 190 patients with nonvalvular paroxysmal AF showing sinus heart rhythm during transesophageal echocardiography (TEE) and TTE.LAA-FV (60 ± 22 cm/s) significantly correlated with the time interval between the initiation of the P-wave on ECG and that of the A-wave of transmitral flow on TTE (PA-TMF, correlation coefficient, -0.32; P < 0.001), LA dimension (LAD, -0.31; P < 0.001), septal a' velocity of tissue Doppler imaging (TDI, 0.35; P < 0.001), E/e' ratio (-0.28, P < 0.001), E velocity of transmitral flow (-0.20, P = 0.008), E/A ratio of transmitral flow (-0.18, P = 0.02), CHA2DS2-VASc score (-0.15, P = 0.04), and BNP plasma level (-0.32, P = 0.002). Multivariate analysis revealed that PA-TMF (standardized partial regression coefficient, -0.17; P = 0.03), a' velocity (0.24, P = 0.004), and LAD (-0.20, P = 0.01) were independent predictors of LAA-FV (multiple correlation coefficient R, 0.44; P < 0.001).Parameters of atrial remodeling, ie, decreased a' velocity, increased LAD, and PA-TMF during sinus rhythm may be useful predictors of LA blood stasis in patients with nonvalvular PAF. LAA-FV can be estimated using these TTE parameters instead of TEE.

  20. [GASTROINTESTINAL COMPLICATIONS OF ANTICOAGULANT THERAPY IN PATIENTS WITH NON-VALVULAR ATRIAL FIBRILLATION].

    PubMed

    Novikova, N A; Volovchenko, A N; Oldakovsky, V I

    2015-01-01

    Non-valvular atrial fibrillation is the most common cardiac source of emboli and cardioembolic stroke. Anticoagulants are recommended for preventing stroke in patients with non-valvular atrial fibrillation. Warfarin reduces the risk of stroke in patients with AF by approximately two-thirds. Several novel anticoagulants that can overcome the limitations of warfarin have been introduced in the market or are under development. The NOACs are at least as effective as warfarin for stroke prevention in AF. Bleeding complications, including gastrointestinal bleeding, are common complication of anticoagulant treatment. The NOACs therapy are associated with an increased risk of major gastrointestinal bleeding compared with warfarin, and dabigatran is associated with an increased risk of non-bleeding upper GI symptoms such as dyspepsia and heartburn. This review provides information on the safety and risks of using NOACs, methods of treatment of gastrointestinal complications events in patients with non-valvular atrial fibrillation. PMID:26817106

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

    PubMed

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

    2013-09-01

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

  2. Multiple Biomarkers and Atrial Fibrillation in the General Population

    PubMed Central

    Schnabel, Renate B.; Wild, Philipp S.; Wilde, Sandra; Ojeda, Francisco M.; Schulz, Andreas; Zeller, Tanja; Sinning, Christoph R.; Kunde, Jan; Lackner, Karl J.

    2014-01-01

    Background Different biological pathways have been related to atrial fibrillation (AF). Novel biomarkers capturing inflammation, oxidative stress, and neurohumoral activation have not been investigated comprehensively in AF. Methods and Results In the population-based Gutenberg Health Study (n = 5000), mean age 56±11 years, 51% males, we measured ten biomarkers representing inflammation (C-reactive protein, fibrinogen), cardiac and vascular function (midregional pro adrenomedullin [MR-proADM], midregional pro atrial natriuretic peptide [MR-proANP], N-terminal pro-B-type natriuretic peptide [Nt-proBNP], sensitive troponin I ultra [TnI ultra], copeptin, and C-terminal pro endothelin-1), and oxidative stress (glutathioneperoxidase-1, myeloperoxidase) in relation to manifest AF (n = 161 cases). Individuals with AF were older, mean age 64.9±8.3, and more often males, 71.4%. In Bonferroni-adjusted multivariable regression analyses strongest associations per standard deviation increase in biomarker concentrations were observed for the natriuretic peptides Nt-proBNP (odds ratio [OR] 2.89, 99.5% confidence interval [CI] 2.14–3.90; P<0.0001), MR-proANP (OR 2.45, 99.5% CI 1.91–3.14; P<0.0001), the vascular function marker MR-proADM (OR 1.54, 99.5% CI 1.20–1.99; P<0.0001), TnI ultra (OR 1.50, 99.5% CI 1.19–1.90; P<0.0001) and. fibrinogen (OR 1.44, 99.5% CI 1.19–1.75; P<0.0001). Based on a model comprising known clinical risk factors for AF, all biomarkers combined resulted in a net reclassification improvement of 0.665 (99.3% CI 0.441–0.888) and an integrated discrimination improvement of >13%. Conclusions In conclusion, in our large, population-based study, we identified novel biomarkers reflecting vascular function, MR-proADM, inflammation, and myocardial damage, TnI ultra, as related to AF; the strong association of natriuretic peptides was confirmed. Prospective studies need to examine whether risk prediction of AF can be enhanced beyond clinical risk

  3. Long-term Prognosis of Paroxysmal Atrial Fibrillation and Predictors for Progression to Persistnt or Chronic Atrial Fibrillation in the Korean Population.

    PubMed

    Im, Sung Ii; Chun, Kwang Jin; Park, Seung-Jung; Park, Kyoung-Min; Kim, June Soo; On, Young Keun

    2015-07-01

    Little is known about the long-term prognosis of or predictors for the different clinical types of atrial fibrillation (AF) in Korean populations. The aim of this study was to validate a risk stratification to assess the probability of AF progression from paroxysmal AF (PAF) to persistent AF (PeAF) or permanent AF. A total of 434 patients with PAF were consecutively enrolled (mean age; 71.7 ± 10.7 yr, 60.6% male). PeAF was defined as episodes that are sustained > 7 days and not self-terminating, while permanent AF was defined as an ongoing long-term episode. Atrial arrhythmia during follow-up was defined as atrial premature complex, atrial tachycardia, and atrial flutter. During a mean follow-up of 72.7 ± 58.3 months, 168 patients (38.7%) with PAF progressed to PeAF or permanent AF. The mean annual AF progression was 10.7% per year. In univariate analysis, age at diagnosis, body mass index, atrial arrhythmia during follow-up, left ventricular ejection fraction, concentric left ventricular hypertrophy, left atrial diameter (LAD), and severe mitral regurgitation (MR) were significantly associated with AF progression. In multivariate analysis, age at diagnosis (P = 0.009), atrial arrhythmia during follow-up (P = 0.015), LAD (P = 0.002) and MR grade (P = 0.026) were independent risk factors for AF progression. Patients with younger age at diagnosis, atrial arrhythmia during follow-up, larger left atrial chamber size, and severe MR grade are more likely to progress to PeAF or permanent AF, suggesting more intensive medical therapy with close clinical follow-up would be required in those patients.

  4. Second harmonic generation imaging of the collagen in myocardium for atrial fibrillation diagnosis

    NASA Astrophysics Data System (ADS)

    Tsai, Ming-Rung; Chiou, Yu-We; Sun, Chi-Kuang

    2009-02-01

    Myocardial fibrosis, a common sequela of cardiac hypertrophy, has been shown to be associated with arrhythmias in experimental models. Some research has indicated that myocardial fibrosis plays an important role in predisposing patients to atrial fibrillation. Second harmonic generation (SHG) is an optically nonlinear coherent process to image the collagen network. In this presentation, we observe the SHG images of the collagen matrix in atrial myocardium and we analyzed of collagen fibers arrangement by using Fourier-transform analysis. Moreover, comparing the SHG images of the collagen fibers in atrial myocardium between normal sinus rhythm (NSR) and atrial fibrillation (AF), our result indicated that it is possible to realize the relation between myocardial fibrosis and AF.

  5. Effect of RAAS blockers on adverse clinical outcomes in high CVD risk subjects with atrial fibrillation

    PubMed Central

    Chaugai, Sandip; Sherpa, Lhamo Yanchang; Sepehry, Amir A.; Arima, Hisatomi; Wang, Dao Wen

    2016-01-01

    Abstract Recent studies have demonstrated that atrial fibrillation significantly increases the risk of adverse clinical outcomes in high cardiovascular disease risk subjects. Application of renin–angiotensin–aldosterone system blockers for prevention of recurrence of atrial fibrillation and adverse clinical outcomes in subjects with atrial fibrillation is a theoretically appealing concept. However, results of clinical trials evaluating the effect of renin–angiotensin–aldosterone blockers on adverse clinical outcomes in high cardiovascular disease risk subjects with atrial fibrillation remain inconclusive. A pooled study of 6 randomized controlled trials assessing the efficacy of renin–angiotensin–aldosterone blockers on subjects with atrial fibrillation was performed. A total of 6 randomized controlled trials enrolled a total of 53,510 patients followed for 1 to 5 years. RAAS blockade therapy was associated with 14% reduction in the incidence of heart failure (OR: 0.86, [95%CI: 0.76– 0.97], P=0.018) and 17% reduction in the incidence of CVE (OR: 0.83, [95%CI: 0.70–0.99], P = 0.038). The corresponding decline in absolute risk against heart failure (ARR: 1.4%, [95%CI: 0.2–2.6%], P = 0.018) and CVE (ARR: 3.5%, [95%CI: 0.0–6.9%], P = 0.045) in the AF group was much higher than the non-AF group for heart failure (ARR: 0.4%, [95%CI: 0.0–0.7%], P = 0.057) and CVE (ARR: 1.6%, [95%CI: –0.1% to 3.3%], P = 0.071). No significant effect was noted on all-cause or cardiovascular mortality, stroke, or myocardial infarction. This study suggests that RAAS blockade offers protection against heart failure and cardiovascular events in high cardiovascular disease risk subjects with atrial fibrillation. PMID:27368043

  6. Signal Transducer and Activator of Transcription 3/MicroRNA-21 Feedback Loop Contributes to Atrial Fibrillation by Promoting Atrial Fibrosis in a Rat Sterile Pericarditis Model

    PubMed Central

    Huang, Zhengrong; Chen, Xiao-jun; Qian, Cheng; Dong, Qian; Ding, Dan; Wu, Qiong-feng; Li, Jing; Wang, Hong-fei; Li, Wei-hua; Xie, Qiang; Cheng, Xiang; Liao, Yu-hua

    2016-01-01

    Background— Postoperative atrial fibrillation is a frequent complication in cardiac surgery. The aberrant activation of signal transducer and activator of transcription 3 (STAT3) contributes to the pathogenesis of atrial fibrillation. MicroRNA-21 (miR-21) promotes atrial fibrosis. Recent studies support the existence of reciprocal regulation between STAT3 and miR-21. Here, we test the hypothesis that these 2 molecules might form a feedback loop that contributes to postoperative atrial fibrillation by promoting atrial fibrosis. Methods and Results— A sterile pericarditis model was created using atrial surfaces dusted with sterile talcum powder in rats. The inflammatory cytokines interleukin (IL)-1β, IL-6, transforming growth factor-β, and tumor necrosis factor-α, along with STAT3 and miR-21, were highly upregulated in sterile pericarditis rats. The inhibition of STAT3 by S3I-201 resulted in miR-21 downregulation, which ameliorated atrial fibrosis and decreased the expression of the fibrosis-related genes, α-smooth muscle actin, collagen-1, and collagen-3; reduced the inhomogeneity of atrial conduction; and attenuated atrial fibrillation vulnerability. Meanwhile, treatment with antagomir-21 decreased STAT3 phosphorylation, alleviated atrial remodeling, abrogated sterile pericarditis–induced inhomogeneous conduction, and prevented atrial fibrillation promotion. The culturing of cardiac fibroblasts with IL-6 resulted in progressively augmented STAT3 phosphorylation and miR-21 levels. S3I-201 blocked IL-6 induced the expression of miR-21 and fibrosis-related genes in addition to cardiac fibroblast proliferation. Transfected antagomir-21 decreased the IL-6–induced cardiac fibroblast activation and STAT3 phosphorylation. The overexpression of miR-21 in cardiac fibroblasts caused the upregulation of STAT3 phosphorylation, enhanced fibrosis-related genes, and increased cell numbers. Conclusions— Our results have uncovered a novel reciprocal loop between STAT3

  7. Prediction of sinus rhythm maintenance following DC-cardioversion of persistent atrial fibrillation – the role of atrial cycle length

    PubMed Central

    Meurling, Carl J; Roijer, Anders; Waktare, Johan EP; Holmqvist, Fredrik; Lindholm, Carl J; Ingemansson, Max P; Carlson, Jonas; Stridh, Martin; Sörnmo, Leif; Olsson, S Bertil

    2006-01-01

    Background Atrial electrical remodeling has been shown to influence the outcome the outcome following cardioversion of atrial fibrillation (AF) in experimental studies. The aim of the present study was to find out whether a non-invasively measured atrial fibrillatory cycle length, alone or in combination with other non-invasive parameters, could predict sinus rhythm maintenance after cardioversion of AF. Methods Dominant atrial cycle length (DACL), a previously validated non-invasive index of atrial refractoriness, was measured from lead V1 and a unipolar oesophageal lead prior to cardioversion in 37 patients with persistent AF undergoing their first cardioversion. Results 32 patients were successfully cardioverted to sinus rhythm. The mean DACL in the 22 patients who suffered recurrence of AF within 6 weeks was 152 ± 15 ms (V1) and 147 ± 14 ms (oesophagus) compared to 155 ± 17 ms (V1) and 151 ± 18 ms (oesophagus) in those maintaining sinus rhythm (NS). Left atrial diameter was 48 ± 4 mm and 44 ± 7 mm respectively (NS). The optimal parameter predicting maintenance of sinus rhythm after 6 weeks appeared to be the ratio of the lowest dominant atrial cycle length (oesophageal lead or V1) to left atrial diameter. This ratio was significantly higher in patients remaining in sinus rhythm (3.4 ± 0.6 vs. 3.1 ± 0.4 ms/mm respectively, p = 0.04). Conclusion In this study neither an index of atrial refractory period nor left atrial diameter alone were predictors of AF recurrence within the 6 weeks of follow-up. The ratio of the two (combining electrophysiological and anatomical measurements) only slightly improve the identification of patients at high risk of recurrence of persistent AF. Consequently, other ways to asses electrical remodeling and / or other variables besides electrical remodeling are involved in determining the outcome following cardioversion. PMID:16533393

  8. Randomised trial of two approaches to screening for atrial fibrillation in UK general practice.

    PubMed Central

    Morgan, Stephen; Mant, David

    2002-01-01

    BACKGROUND: Atrial fibrillation is a common and treatable cause of stroke that often remains unrecognised. Screening has been suggested but there is very little evidence concerning the uptake of screening in the elderly population at risk, nor of the optimal method of screening in a general practice setting AIM: To compare the uptake and effectiveness of two methods of screening for atrial fibrillation in general practice--systematic nurse-led screening and prompted opportunistic case finding. DESIGN OF STUDY: Randomised controlled trial. SETTING: Patients aged 65 to 100 years (n = 3,001) from four general practices within the MRC general practice framework. METHOD: Each of the four study practices were selected from one quartile, after ranking all framework practices according to the small area standardised mortality ratio of the geographical area served. Patients were randomised either to nurse-led screening or to prompted opportunistic casefinding. The proportion of patients assessed and the proportion found to have atrial fibrillation were compared. The sensitivity and specificity of clinical assessment of pulse are also reported. RESULTS: Substantially more patients had their pulse assessed through systematic screening by invitation (1,099/1,499 [73%]) than through opportunistic case finding (439/1,502 [29%], difference = 44%, 95% confidence interval [CI] = 41% to 47%). Atrial fibrillation was detected in 67 (4.5%) and 19 (1.3%) patients respectively (difference = 3.2%, 95% CI= 2.0 to 4.4). Invitation to nurse-led screening achieved significantly higher assessment rates than case finding in all practices; however, the proportion of patients assessed in the case-finding arm varied markedly between practices (range = 8% to 52%). The number needed to screen to identify one additional patient with atrial fibrillation was 31 (95% CI = 23 to 50). The proportion of screened patients with atrial fibrillation receiving anticoagulation treatment was 25%, although in the

  9. An accessory bypass tract masked by the presence of atrial fibrillation in a horse.

    PubMed

    Jesty, Sophy A; Kraus, Marc S; Johnson, Amy L; Gelzer, Anna R M; Bartol, Jacqueline

    2011-03-01

    Accessory bypass tracts are rarely documented in horses. Here, we present a case of an accessory bypass tract which was initially masked by the presence of atrial fibrillation. Evidence of ventricular pre-excitation was recognized after cardioversion to normal sinus rhythm and the horse was diagnosed with Wolff-Parkinson-White Syndrome. In people, atrial fibrillation in the presence of an accessory bypass tract is considered dangerous due to the risk of sudden cardiac death. Although we did not consider this horse safe to ride, he continues to compete successfully and has not had recurrence of clinically significant tachyarrhythmias.

  10. Spontaneous normal sinus rhythm conversion using integrative medicine in atrial fibrillation.

    PubMed

    Farrar, Wendy S; Fyfe-Johnson, Amber L; Baechler, Courtney J; Dusek, Jeffery A

    2012-05-01

    The relationship between acute life stress and the development of atrial fibrillation (AF) has been noted in the literature. However, the use of integrative medicine (IM) in restoring cardiac rhythm has not been adequately studied. This case report describes how an IM approach was used in a patient with atrial fibrillation and acute pain. Spontaneous cardioversion to normal sinus rhythm occurred during the IM session, in addition to marked decreases in self-reported pain, anxiety, and nausea at the conclusion of IM treatment. These results provide initial support that for some cases of AF, IM therapies can help to reduce costs via avoidance of additional hospitalization, electrocardioversion, and general anesthesia.

  11. Acute renal infarction secondary to atrial fibrillation - mimicking renal stone picture.

    PubMed

    Salih, Salih Bin; Al Durihim, Huda; Al Jizeeri, Ahmed; Al Maziad, Ghassan

    2006-06-01

    Acute renal infarction presents in a similar clinical picture to that of a renal stone. We report a 55-year-old Saudi female, known to have atrial fibrillation secondary to mitral stenosis due to rheumatic heart disease. She presented with a two day history of right flank pain that was treated initially as a renal stone. Further investigations confirmed her as a case of renal infarction. Renal infarction is under-diagnosed because the similarity of its presentation to renal stone. Renal infarction should be considered in the differential diagnosis of loin pain, particularly in a patient with atrial fibrillation.

  12. Mortality of atrial fibrillation in a population selected to be free of major cardiovascular impairments.

    PubMed

    Iacovino, J R

    1999-01-01

    The magnitude of additional mortality produced by the development of atrial fibrillation not associated with major cardiovascular risk factors is demonstrated. In a community-based population followed for 10 years, men aged 55-74 years had a mortality ratio of 260% and an excess death rate of 57. Women in the same age group had a mortality ratio of 335% and an excess death rate of 59. Were one to use an industry expected life table instead of the author's selected community population, the mortality ratios and excess death rates would be higher. Charging an extra premium for individuals with atrial fibrillation is supported by this increased mortality risk.

  13. Late Sodium Current in Human Atrial Cardiomyocytes from Patients in Sinus Rhythm and Atrial Fibrillation

    PubMed Central

    Poulet, Claire; Wettwer, Erich; Grunnet, Morten; Jespersen, Thomas; Fabritz, Larissa; Matschke, Klaus; Knaut, Michael; Ravens, Ursula

    2015-01-01

    Slowly inactivating Na+ channels conducting “late” Na+ current (INa,late) contribute to ventricular arrhythmogenesis under pathological conditions. INa,late was also reported to play a role in chronic atrial fibrillation (AF). The objective of this study was to investigate INa,late in human right atrial cardiomyocytes as a putative drug target for treatment of AF. To activate Na+ channels, cardiomyocytes from transgenic mice which exhibit INa,late (ΔKPQ), and right atrial cardiomyocytes from patients in sinus rhythm (SR) and AF were voltage clamped at room temperature by 250-ms long test pulses to -30 mV from a holding potential of -80 mV with a 100-ms pre-pulse to -110 mV (protocol I). INa,late at -30 mV was not discernible as deviation from the extrapolated straight line IV-curve between -110 mV and -80 mV in human atrial cells. Therefore, tetrodotoxin (TTX, 10 μM) was used to define persistent inward current after 250 ms at -30 mV as INa,late. TTX-sensitive current was 0.27±0.06 pA/pF in ventricular cardiomyocytes from ΔKPQ mice, and amounted to 0.04±0.01 pA/pF and 0.09±0.02 pA/pF in SR and AF human atrial cardiomyocytes, respectively. With protocol II (holding potential -120 mV, pre-pulse to -80 mV) TTX-sensitive INa,late was always larger than with protocol I. Ranolazine (30 μM) reduced INa,late by 0.02±0.02 pA/pF in SR and 0.09±0.02 pA/pF in AF cells. At physiological temperature (37°C), however, INa,late became insignificant. Plateau phase and upstroke velocity of action potentials (APs) recorded with sharp microelectrodes in intact human trabeculae were more sensitive to ranolazine in AF than in SR preparations. Sodium channel subunits expression measured with qPCR was high for SCN5A with no difference between SR and AF. Expression of SCN8A and SCN10A was low in general, and lower in AF than in SR. In conclusion, We confirm for the first time a TTX-sensitive current (INa,late) in right atrial cardiomyocytes from SR and AF patients at room

  14. Late Sodium Current in Human Atrial Cardiomyocytes from Patients in Sinus Rhythm and Atrial Fibrillation.

    PubMed

    Poulet, Claire; Wettwer, Erich; Grunnet, Morten; Jespersen, Thomas; Fabritz, Larissa; Matschke, Klaus; Knaut, Michael; Ravens, Ursula

    2015-01-01

    Slowly inactivating Na+ channels conducting "late" Na+ current (INa,late) contribute to ventricular arrhythmogenesis under pathological conditions. INa,late was also reported to play a role in chronic atrial fibrillation (AF). The objective of this study was to investigate INa,late in human right atrial cardiomyocytes as a putative drug target for treatment of AF. To activate Na+ channels, cardiomyocytes from transgenic mice which exhibit INa,late (ΔKPQ), and right atrial cardiomyocytes from patients in sinus rhythm (SR) and AF were voltage clamped at room temperature by 250-ms long test pulses to -30 mV from a holding potential of -80 mV with a 100-ms pre-pulse to -110 mV (protocol I). INa,late at -30 mV was not discernible as deviation from the extrapolated straight line IV-curve between -110 mV and -80 mV in human atrial cells. Therefore, tetrodotoxin (TTX, 10 μM) was used to define persistent inward current after 250 ms at -30 mV as INa,late. TTX-sensitive current was 0.27±0.06 pA/pF in ventricular cardiomyocytes from ΔKPQ mice, and amounted to 0.04±0.01 pA/pF and 0.09±0.02 pA/pF in SR and AF human atrial cardiomyocytes, respectively. With protocol II (holding potential -120 mV, pre-pulse to -80 mV) TTX-sensitive INa,late was always larger than with protocol I. Ranolazine (30 μM) reduced INa,late by 0.02±0.02 pA/pF in SR and 0.09±0.02 pA/pF in AF cells. At physiological temperature (37°C), however, INa,late became insignificant. Plateau phase and upstroke velocity of action potentials (APs) recorded with sharp microelectrodes in intact human trabeculae were more sensitive to ranolazine in AF than in SR preparations. Sodium channel subunits expression measured with qPCR was high for SCN5A with no difference between SR and AF. Expression of SCN8A and SCN10A was low in general, and lower in AF than in SR. In conclusion, We confirm for the first time a TTX-sensitive current (INa,late) in right atrial cardiomyocytes from SR and AF patients at room

  15. Atrial fibrillation in the elderly -- not a benign condition.

    PubMed

    Lee, Geraldine A; Stub, Dion; Ling, Han

    2012-10-01

    Atrial fibrillation (AF) is the most commonly seen arrhythmia and its prevalence increases with age. In the general population, rates of 1-2% are reported but in older patients, the rates increase to over 10% (in those aged 85years or older). Many older patients present to the emergency department (ED) with complaints that could be caused or associated with AF including valvular heart disease, hypertension, heart failure, an underlying infection (urinary or chest) and thyroid disorder. The most devastating complication of AF is stroke and early detection of AF and initiation of treatment (specifically the use of anti-coagulant medication) can significantly reduce the risk. AF is associated with high healthcare costs and has significant impacts on disability and quality of life especially if a stroke occurs. This review aims to describe the aetiology and treatment options for patients with newly diagnosed and previously diagnosed AF with an emphasis on how ED staff can manage older patients with AF and ensure optimal care is given. The treatment of AF has three main considerations (i) appropriateness for thromboembolic prophylaxis, (ii) rate control (including anti-arrhythmics, cardiac glycosides, B blockers and calcium channel blockers) and (iii) rhythm control with traditional cardioversion (either electrically or pharmacologically) or utilising interventional means to maintain sinus rhythm with cardiac surgery and more recently radio-frequency ablation. As anti-coagulation is widely implemented, the risks and benefits associated with warfarin and the newer agents will be described. Given that more than half of those with AF are over 75years and 30% of AF is diagnosed incidentally, there is an imperative for prompt diagnosis to reduce the risk of debilitating complications especially stroke. AF should not be viewed as yet another concomitant "benign" condition. Emergency staff are well placed to detect AF and ensure appropriate treatment is commenced to reduce the

  16. Emerging anticoagulant therapies for atrial fibrillation: new options, new challenges.

    PubMed

    Mangiafico, R A; Mangiafico, M

    2012-01-01

    Atrial fibrillation (AF), the most common cardiac arrhythmia, is associated with an increased risk of stroke and systemic embolism. Oral anticoagulation with vitamin K antagonists (VKAs), such as warfarin, has historically been the mainstay of long-term thromboprophylaxis in AF patients. However, although highly effective, VKAs have a number of limitations that make their use difficult and cumbersome in clinical practice. They have a slow onset and offset of action, narrow therapeutic window, marked dose-response variability, and multiple food and drug interactions, and require frequent coagulation monitoring and dose adjustments. To overcome VKA drawbacks, several new oral anticoagulants have been recently developed for use in AF, and three of them, the direct thrombin inhibitor dabigatran etexilate and the direct factor Xa inhibitors rivaroxaban and apixaban, have completed phase III trials. New agents have proven to be noninferior or superior to warfarin for AF-related stroke prevention, with similar or better safety profiles. These new drugs, with their predictable anticoagulant effect that allows for fixed dosing with no need for coagulation monitoring, have the potential to greatly simplify anticoagulation therapy for AF. Dabigatran etexilate and rivaroxaban are already approved in the United States and Europe for stroke prevention in nonvalvular AF, and dabigatran etexilate has entered current AF guidelines as an alternative to warfarin. However, some issues with new compounds are still unresolved, such as the lack of antidotes and standardized tests to measure drug activity. Active postmarketing monitoring surveillance of effectiveness and safety is required in the implementation of new anticoagulant therapies. PMID:22830344

  17. Dabigatran and Rivaroxaban Use in Atrial Fibrillation Patients on Hemodialysis

    PubMed Central

    Chan, Kevin E.; Edelman, Elazer R.; Wenger, Julia B.; Thadhani, Ravi I.; Maddux, Franklin W.

    2015-01-01

    Background Dabigatran and rivaroxaban are new oral anticoagulants that are eliminated through the kidneys. Their use in dialysis patients is discouraged because these drugs can bio-accumulate to precipitate inadvertent bleeding. We wanted to determine if prescription of dabigatran or rivaroxaban was occurring in the dialysis population and if these practices were safe. Methods and Results Prevalence plots were used to describe the point prevalence (monthly) of dabigatran and rivaroxaban use among 29,977 hemodialysis patients with atrial fibrillation (AF). Poisson regression compared the rate of bleeding, stroke, and arterial embolism in patients who started dabigatran, rivaroxaban, or warfarin. The first record of dabigatran prescription among hemodialysis patients occurred 45 days after the drug became available in the US. Since then, dabigatran and rivaroxaban use in the AF-ESRD population has steadily risen where 5.9% of anti-coagulated dialysis patients are started on dabigatrian or rivaroxaban. In covariate adjusted Poisson regression, dabigatran (RR=1.48; 95% CI 1.21-1.81, p=0.0001) and rivaroxaban (RR=1.38; 95% CI 1.03-1.83, p=0.04) associated with a higher risk of hospitalization or death from bleeding when compared to warfarin. The risk of hemorrhagic death was even larger with dabigatran (RR=1.78; 95% CI 1.18-2.68, p=0.006) and rivaroxaban (RR=1.71; 95% CI 0.94-3.12, p=0.07) relative to warfarin. There were too few events in the study to detect meaningful differences in stroke and arterial embolism between the drug groups. Conclusions More dialysis patients are being started on dabigatran and rivaroxaban, even when their use is contraindicated and there are no studies to support the benefits outweigh the risks of these drugs in ESRD. PMID:25595139

  18. Automated planning of ablation targets in atrial fibrillation treatment

    NASA Astrophysics Data System (ADS)

    Keustermans, Johannes; De Buck, Stijn; Heidbüchel, Hein; Suetens, Paul

    2011-03-01

    Catheter based radio-frequency ablation is used as an invasive treatment of atrial fibrillation. This procedure is often guided by the use of 3D anatomical models obtained from CT, MRI or rotational angiography. During the intervention the operator accurately guides the catheter to prespecified target ablation lines. The planning stage, however, can be time consuming and operator dependent which is suboptimal both from a cost and health perspective. Therefore, we present a novel statistical model-based algorithm for locating ablation targets from 3D rotational angiography images. Based on a training data set of 20 patients, consisting of 3D rotational angiography images with 30 manually indicated ablation points, a statistical local appearance and shape model is built. The local appearance model is based on local image descriptors to capture the intensity patterns around each ablation point. The local shape model is constructed by embedding the ablation points in an undirected graph and imposing that each ablation point only interacts with its neighbors. Identifying the ablation points on a new 3D rotational angiography image is performed by proposing a set of possible candidate locations for each ablation point, as such, converting the problem into a labeling problem. The algorithm is validated using a leave-one-out-approach on the training data set, by computing the distance between the ablation lines obtained by the algorithm and the manually identified ablation points. The distance error is equal to 3.8+/-2.9 mm. As ablation lesion size is around 5-7 mm, automated planning of ablation targets by the presented approach is sufficiently accurate.

  19. Adherence to guideline recommendations for antiarrhythmic drugs in atrial fibrillation

    PubMed Central

    Allen LaPointe, Nancy M.; Lokhnygina, Yuliya; Sanders, Gillian D.; Peterson, Eric D.; Al-Khatib, Sana M.

    2013-01-01

    Background Atrial fibrillation (AF) guideline recommendations for antiarrhythmic drugs (AADs) are based upon the effectiveness and safety of the AAD in patients with selected, concomitant heart disease. It is unknown to what extent these recommendations are being implemented in clinical practice. Methods Using commercial health claims, patients with AF were identified and then categorized into mutually exclusive, guideline-established subgroups based upon their most serious concurrent heart disease: heart failure, coronary artery disease (CAD), hypertension, no heart disease. AAD use following the first AF encounter and the identified concurrent heart disease encounter was determined from prescription claims, and this was compared with guideline recommendations. Results From January 2006 through December 2010, a total of 331,274 AF patients aged <65 years were identified: 18% heart failure, 23% CAD, 33% hypertension, and 25% no heart disease. Of these, 78,877 (24%) patients filled ≥1 qualifying AAD prescription. The median age was 57 years (interquartile range 52, 61), and 69% were male. A total of 74,191 patients had AADs after both the AF and concurrent heart disease encounters: 27% with heart failure, 25% with CAD, 21% with hypertension, and 19% with no heart disease. In the heart failure and CAD subgroups, 45% and 31% of AADs were inconsistent with first- or second-line guideline recommendations, respectively. Conclusion More than one-third of the AADs used in AF patients with CAD or heart failure did not conform to guideline recommendations. This highlights the potential need for increased clinician education and intervention to improve the safe use of AADs for AF management. PMID:24176443

  20. Stroke prevention in atrial fibrillation--an Asian stroke perspective.

    PubMed

    Tse, Hung-Fat; Wang, Yong-Jun; Ahmed Ai-Abdullah, Moheeb; Pizarro-Borromeo, Annette B; Chiang, Chern-En; Krittayaphong, Rungroj; Singh, Balbir; Vora, Amit; Wang, Chun-Xue; Zubaid, Mohammad; Clemens, Andreas; Lim, Paul; Hu, Dayi

    2013-07-01

    Despite relatively lower prevalence of atrial fibrillation (AF) in Asians (~1%) than in Caucasians (~2%), Asia has a much higher overall disease burden because of its proportionally larger aged population. For example, on the basis of reported age-adjusted prevalence rates and projected population figures in China, there will be an estimated 5.2 million men and 3.1 million women with AF older than 60 years by year 2050. Stroke is a disabling complication of AF that is of increasing cause for concern in Asians patients. Implementing consensus expert recommendations for managing stroke risk in patients with AF can considerably reduce stroke rates. However, caution is necessary when aligning management of Asian patients with AF to that of their Caucasian counterparts. Current international guidelines and risk stratification tools for AF management are based on findings in predominantly Caucasian populations and may therefore have limited relevance, in certain respects, to Asian patients. Oral anticoagulants play an important role in preventing AF-related stroke. The vitamin K antagonist warfarin is recommended for reducing the risk of stroke and thromboembolism in high-risk patients with nonvalvular AF; however, warfarin interacts with many drugs and food ingredients, which may pose significant challenges in administration and monitoring among Asian patients. Further research is needed to inform specific guidance on the implications of different stroke and bleeding profiles in Asians vs Caucasians. Moreover, there is scope to improve physician perceptions and patient knowledge, as well as considering alternative new oral anticoagulants, for example, direct thrombin inhibitors or factor Xa inhibitors.

  1. The changing characteristics of atrial fibrillation patients treated with warfarin

    PubMed Central

    Gu, Xiaokui; Haymart, Brian; Kline-Rogers, Eva; Almany, Steve; Kozlowski, Jay; Krol, Gregory D.; Kaatz, Scott; Froehlich, James B.; Barnes, Geoffrey D.

    2016-01-01

    It has been suggested that direct oral anticoagulants are being preferentially used in low risk atrial fibrillation (AF) patients. Understanding the changing risk profile of new AF patients treated with warfarin is important for interpreting the quality of warfarin delivery through an anticoagulation clinic. Six anticoagulation clinics participating in the Michigan Anticoagulation Quality Improvement Initiative enrolled 1293 AF patients between 2010 and 2014 as an inception cohort. Abstracted data included demographics, comorbidities, medication use and all INR values. Risk scores including CHADS2, CHA2DS2-VASc, HAS-BLED, SAMe-TT2R2, and Charlson comorbidity index (CCI) were calculated for each patient at the time of warfarin initiation. The quality of anticoagulation was assessed using the Rosendaal time in the therapeutic range (TTR) during the first 6 months of treatment. Between 2010 and 2014, patients initiating warfarin therapy for AF had an increasing mean CHADS2 (2.0 ± 1.1 to 2.2 ± 1.4, p = 0.02) and CCI (4.7 ± 1.8 to 5.1 ± 2.0, p = 0.03), and a trend towards increasing mean CHA2DS2-VASc, HAS-BLED, and SAMe-TT2R2 scores. The actual TTR remained unchanged over the study period (62.6 ± 18.2 to 62.7 ± 17.0, p = 0.98), and the number of INR checks did not change (18.9 ± 5.2 to 18.5 ± 5.1, p = 0.06). Between 2010 and 2014, AF patients newly starting warfarin had mild increases in risk for stroke and death with sustained quality of warfarin therapy. PMID:26130229

  2. Asian strategy for stroke prevention in atrial fibrillation.

    PubMed

    Chiang, Chern-En; Wang, Kang-Ling; Lin, Shing-Jong

    2015-10-01

    Atrial fibrillation (AF) has become a major health burden in Asia. It is estimated that in year 2050 Asia will have 72 million AF patients, and 2.9 million among them will suffer from AF-associated stroke. Asian AF patients have similar cardiovascular co-morbidities as westerns, and the recently developed CHA2DS2-VASc score remains valid in predicting stroke risk in Asians, outperforming other scoring systems. There is little evidence supporting a role of aspirin in preventing AF-associated stroke in Asians. Warfarin is effective for the prevention of stroke in Asians, but is very difficult to use. Warfarin-induced bleeding events are more common in Asians. Four major clinical trials have been performed to test non-vitamin K antagonist oral anticoagulants (NOACs) vs. warfarin in the stroke prevention in AF. Warfarin produced higher risk of major bleeding and intra-cranial haemorrhage in Asians compared with those in non-Asians, even though anticoagulation intensity was lower in Asians. All these trials consistently demonstrated that NOACs were superior or non-inferior to warfarin. The benefits of NOACs were especially robust in Asians. The relative risk reduction in most of the efficacy endpoints and the safety endpoints was numerically greater in Asians than in non-Asians. There was no evidence of increased risk of gastro-intestinal bleeding associated with NOACs in Asians. Unless in a few conditions when NOACs are contraindicated, NOACs are preferred medications in the stroke prevention for AF in Asians. PMID:26842113

  3. Relation of vigorous exercise to risk of atrial fibrillation.

    PubMed

    Aizer, Anthony; Gaziano, J Michael; Cook, Nancy R; Manson, Joann E; Buring, Julie E; Albert, Christine M

    2009-06-01

    Limited data suggest that athletes may have a higher risk of developing atrial fibrillation (AF); however, there has been no large prospective assessment of the relation between vigorous exercise and AF. Logistic regression analyses stratified by time were used to assess the association between frequency of vigorous exercise and risk of developing AF in 16,921 apparently healthy men in the Physicians' Health Study. During 12 years of follow-up, 1,661 men reported developing AF. With increasing frequency of vigorous exercise (0, 1, 1 to 2, 3 to 4, 5 to 7 days/week), multivariate relative risks for the full cohort were 1.0 (referent), 0.90, 1.09, 1.04, and 1.20 (p = 0.04). This risk was not significantly increased when exercise habits were updated or in models excluding variables that may be in the biological pathway through which exercise influences AF risk. In subgroup analyses, this increased risk was observed only in men <50 years of age (1.0, 0.94, 1.20, 1.05, 1.74, p <0.01) and joggers (1.0, 0.91, 1.03, 1.30, 1.53, p <0.01), where risks remained increased in all analyses. In conclusion, frequency of vigorous exercise was associated with an increased risk of developing AF in young men and joggers. This risk decreased as the population aged and was offset by known beneficial effects of vigorous exercise on other AF risk factors.

  4. New anticoagulants for the prevention of stroke in atrial fibrillation.

    PubMed

    Höchtl, Thomas; Huber, Kurt

    2012-02-01

    Oral anticoagulation in atrial fibrillation is obligatory to lower the risk of spontaneous cerebrovascular and systemic thromboembolism. For this purpose, vitamin K antagonists (coumarins) have been recommended as the most effective drugs for a long time. However, problems with the practical use of these agents, e.g. the need for frequent and regular coagulation controls, the inter-individual differences in maintaining a stable therapeutic range, as well as drug or food interactions, have led to the search and investigation of alternative compounds characterized by a more simple use (e.g. without regular controls of therapeutic levels), high efficacy, as well as low risk of bleeding. The direct thrombin inhibitor dabigatran and the direct factor Xa inhibitors rivaroxaban and apixaban have recently been investigated to prove whether they fulfill the high expectancy of an ideal anticoagulant with respect to a more favorable efficacy/safety profile and without the need for coagulation controls, thereby improving quality of life. Dabigatran (RE-LY) achieved an impressive reduction in stroke and non-central nervous system (non-CNS) embolism (110 mg: 1.5%/year; 150 mg: 1.1%/year) in contrast to warfarin (1.7%/year; P = 0.34 and P < 0.001) with a favorable action on bleeding hazards. The results of rivaroxaban which were obtained in the ROCKET AF study (on treatment analysis: stroke and non-CNS embolism: 1.7%/year vs. 2.15%/year with warfarin; P = 0.015; primary safety endpoint major and minor bleeding: 14.91 vs. 14.52%; P = 0.442) point in the same direction. And finally, compared to aspirin, apixaban reduced the combined primary efficacy endpoint by 52% with comparable rates of bleeding (AVERROES). This review gives a summary of the current knowledge about these agents and their potential future importance. PMID:21883447

  5. Spectral characteristics of ventricular response to atrial fibrillation.

    PubMed

    Hayano, J; Yamasaki, F; Sakata, S; Okada, A; Mukai, S; Fujinami, T

    1997-12-01

    To investigate the spectral characteristics of the fluctuation in ventricular response during atrial fibrillation (AF), R-R interval time series obtained from ambulatory electrocardiograms were analyzed in 45 patients with chronic AF and in 30 age-matched healthy subjects with normal sinus rhythm (SR). Although the 24-h R-R interval spectrum during SR showed a 1/f noise-like downsloping linear pattern when plotted as log power against log frequency, the spectrum during AF showed an angular shape with a breakpoint at a frequency of 0.005 +/- 0.002 Hz, by which the spectrum was separated into long-term and short-term components with different spectral characteristics. The short-term component showed a white noise-like flat spectrum with a spectral exponent (absolute value of the regression slope) of 0.05 +/- 0.08 and an intercept at 10(-2) Hz of 4.9 +/- 0.3 log(ms2/Hz). The long-term component had a 1/f noise-like spectrum with a spectral exponent of 1.26 +/- 0.40 and an intercept at 10(-4) Hz of 7.0 +/- 0.3 log(ms2/Hz), which did not differ significantly from those for the spectrum during SR in the same frequency range [spectral exponent, 1.36 +/- 0.06; intercept at 10(-4) Hz, 7.1 +/- 0.3 log(ms2/Hz)]. The R-R intervals during AF may be a sequence of uncorrelated values over the short term (within several minutes). Over the longer term, however, the R-R interval fluctuation shows the long-range negative correlation suggestive of underlying regulatory processes, and spectral characteristics indistinguishable from those for SR suggest that the long-term fluctuations during AF and SR may originate from similar dynamics of the cardiovascular regulatory systems. PMID:9435618

  6. Syndecan-4 shedding is involved in the oxidative stress and inflammatory responses in left atrial tissue with valvular atrial fibrillation

    PubMed Central

    Wu, Han; Zhou, Qing; Xie, Jun; Li, Guan-Nan; Chen, Qin-Hua; Kang, Li-Na; Xu, Biao

    2015-01-01

    Oxidative stress and inflammation play critical roles in the development and maintenance of atrial fibrillation (AF). In addition, syndecan-4 (Synd4) shedding induced by oxidative stress or inflammation plays a role in the migration of inflammatory cells. Therefore, we hypothesized that Synd4 shedding was also involved in the inflammatory response in atrial fibrillation patients with valvular heart disease. To confirm this suppose, left atrial appendages and clinical data were obtained from 65 patients with valvular disease undergoing valve surgery. Ten left atrial appendages obtained from healthy heart donors were used as controls. Analyses including histopathology, western blotting, and enzyme kinetics were performed to assess the oxidative injury, inflammation responses, and Synd4 shedding. The results showed that the inflammatory response and oxidative injury were increased significantly, whereas as levels of the Synd4 ectodomain was decreased significantly in AF patients. Furthermore, Synd4 ectodomain levels were correlated with atrial oxidative and inflammatory markers. The results showed that Synd4 shedding is a molecular pathological alteration in the development and maintenance of inflammation-associated AF. PMID:26261514

  7. Left Atrial Appendage Morphology in Patients with Suspected Cardiogenic Stroke without Known Atrial Fibrillation

    PubMed Central

    Korhonen, Miika; Muuronen, Antti; Arponen, Otso; Mustonen, Pirjo; Hedman, Marja; Jäkälä, Pekka; Vanninen, Ritva; Taina, Mikko

    2015-01-01

    The left atrial appendage (LAA) is the typical origin for intracardiac thrombus formation. Whether LAA morphology is associated with increased stroke/TIA risk is controversial and, if it does, which morphological type most predisposes to thrombus formation. We assessed LAA morphology in stroke patients with cryptogenic or suspected cardiogenic etiology and in age- and gender-matched healthy controls. LAA morphology and volume were analyzed by cardiac computed tomography in 111 patients (74 males; mean age 60 ± 11 years) with acute ischemic stroke of cryptogenic or suspected cardiogenic etiology other than known atrial fibrillation (AF). A subgroup of 40 patients was compared to an age- and gender-matched control group of 40 healthy individuals (21 males in each; mean age 54 ± 9 years). LAA was classified into four morphology types (Cactus, ChickenWing, WindSock, CauliFlower) modified with a quantitative qualifier. The proportions of LAA morphology types in the main stroke group, matched stroke subgroup, and control group were as follows: Cactus (9.0%, 5.0%, 20.0%), ChickenWing (23.4%, 37.5%, 10.0%), WindSock (47.7%, 35.0%, 67.5%), and CauliFlower (19.8%, 22.5%, 2.5%). The distribution of morphology types differed significantly (P<0.001) between the matched stroke subgroup and control group. The proportion of single-lobed LAA was significantly higher (P<0.001) in the matched stroke subgroup (55%) than the control group (6%). LAA volumes were significantly larger (P<0.001) in both stroke study groups compared to controls patients. To conclude, LAA morphology differed significantly between stroke patients and controls, and single-lobed LAAs were overrepresented and LAA volume was larger in patients with acute ischemic stroke of cryptogenic or suspected cardiogenic etiology. PMID:25751618

  8. Early Experience Using a Left Atrial Appendage Occlusion Device in Patients with Atrial Fibrillation

    PubMed Central

    Kim, Yung Ly; Joung, Boyoung; On, Young Keun; Shim, Chi Young; Lee, Moon Hyoung; Kim, Young-Hoon

    2012-01-01

    Purpose Atrial fibrillation (AF) is one of the major risk factors for ischemic stroke, and 90% of thromboembolisms in these patients arise from the left atrial appendage (LAA). Recently, it has been documented that an LAA occlusion device (OD) is not inferior to warfarin therapy, and that it reduces mortality and risk of stroke in patients with AF. Materials and Methods We implanted LAA-ODs in 5 Korean patients (all male, 59.8±7.3 years old) with long-standing persistent AF or permanent AF via a percutaneous trans-septal approach. Results 1) The major reasons for LAA-OD implantation were high risk of recurrent stroke (80%), labile international neutralizing ratio with hemorrhage (60%), and 3/5 (60%) patients had a past history of failed cardioversion for rhythm control. 2) The mean LA size was 51.3±5.0 mm and LAA size was 25.1×30.1 mm. We implanted the LAA-OD (28.8±3.4 mm device) successfully in all 5 patients with no complications. 3) After eight weeks of anticoagulation, all patients switched from warfarin to anti-platelet agent after confirmation of successful LAA occlusion by trans-esophageal echocardiography. Conclusion We report on our early experience with LAA-OD deployment in patients with 1) persistent or permanent AF who cannot tolerate anticoagulation despite significant risk of ischemic stroke, or 2) recurrent stroke in patients who are unable to maintain sinus rhythm. PMID:22187236

  9. Oxidative Stress in Atrial Fibrillation: An Emerging Role of NADPH Oxidase

    PubMed Central

    Youn, Ji-Youn; Zhang, Jun; Zhang, Yixuan; Chen, Houzao; Liu, Depei; Ping, Peipei; Weiss, James N.; Cai, Hua

    2013-01-01

    Atrial fibrillation (AF) is the most common cardiac arrhythmia. Patients with AF have up to seven-fold higher risk of suffering from ischemic stroke. Better understanding of etiologies of AF and its thromboembolic complications are required for improved patient care, as current anti-arrhythmic therapies have limited efficacy and off target effects. Accumulating evidence has implicated a potential role of oxidative stress in the pathogenesis of AF. Excessive production of reactive oxygen species (ROS) is likely involved in the structural and electrical remodeling of the heart, contributing to fibrosis and thrombosis. In particular, NADPH oxidase (NOX) has emerged as a potential enzymatic source for ROS production in AF based on growing evidence from clinical and animal studies. Indeed, NOX can be activated by known upstream triggers of AF such as angiotensin II and atrial stretch. In addition, treatments such as Statins, antioxidants, ACEI or AT1RB have been shown to prevent post-operative AF; among which ACEI/AT1RB and Statins can attenuate NOX activity. On the other hand, detailed molecular mechanisms by which specific NOX isoform(s) are involved in the pathogenesis of AF and the extent to which activation of NOX plays a causal role in AF development remains to be determined. The current review discusses causes and consequences of oxidative stress in AF with a special focus on the emerging role of NOX pathways. PMID:23643589

  10. Identifying Future Research Priorities Using Value of Information Analyses: Left Atrial Appendage Occlusion Devices in Atrial Fibrillation

    PubMed Central

    Micieli, Andrew; Bennell, Maria C.; Pham, Ba’; Krahn, Murray; Singh, Sheldon M.; Wijeysundera, Harindra C.

    2014-01-01

    Background Left atrial appendage occlusion devices are cost effective for stroke prophylaxis in atrial fibrillation when compared with dabigatran or warfarin. We illustrate the use of value‐of‐information analyses to quantify the degree and consequences of decisional uncertainty and to identify future research priorities. Methods and Results A microsimulation decision‐analytic model compared left atrial appendage occlusion devices to dabigatran or warfarin in atrial fibrillation. Probabilistic sensitivity analysis quantified the degree of parameter uncertainty. Expected value of perfect information analyses showed the consequences of this uncertainty. Expected value of partial perfect information analyses were done on sets of input parameters (cost, utilities, and probabilities) to identify the source of the greatest uncertainty. One‐way sensitivity analyses identified individual parameters for expected value of partial perfect information analyses. Population expected value of perfect information and expected value of partial perfect information provided an upper bound on the cost of future research. Substantial uncertainty was identified, with left atrial appendage occlusion devices being preferred in only 47% of simulations. The expected value of perfect information was $8542 per patient and $227.3 million at a population level. The expected value of partial perfect information for the set of probability parameters represented the most important source of uncertainty, at $6875. Identified in 1‐way sensitivity analyses, the expected value of partial perfect information for the odds ratio for stroke with left atrial appendage occlusion compared with warfarin was calculated at $7312 per patient or $194.5 million at a population level. Conclusion The relative efficacy of stroke reduction with left atrial appendage occlusion devices in relation to warfarin is an important source of uncertainty. Improving estimates of this parameter should be the priority

  11. Assessing bleeding risk in 4824 Asian patients with atrial fibrillation: The Beijing PLA Hospital Atrial Fibrillation Project.

    PubMed

    Guo, Yu-Tao; Zhang, Ye; Shi, Xiang-Min; Shan, Zhao-Liang; Wang, Chun-Jiang; Wang, Yu-Tang; Chen, Yun-Dai; Lip, Gregory Y H

    2016-01-01

    The risks of major bleeding and intracranial hemorrhage (ICH) are higher in Asian patients with atrial fibrillation (AF) compared to non-Asians. We aimed to investigate risk factors for bleeding, and validate the predictive value of available bleeding risk scores (mOBRI, HEMORR2HAGES, Shireman, HAS-BLED, ATRIA and ORBIT) in a large cohort of Chinese inpatients with AF. Using hospital electronic medical databases, we identified 4824 AF patients (mean age 67 years; 34.9% female) from January 1, 1995 to May 30, 2015, with median (interquartile) in-hospital days of 10 (7-16) days. On multivariate analysis, prior bleeds, vascular disease, anemia, prior stroke, and liver dysfunction were independent risk factors of major bleeding (all p < 0.05). C-statistics (95%CI) of the HAS-BLED score were 0.72 (0.65-0.79) for major bleeding events and 0.83 (0.75-0.91) for ICH (all p < 0.001). Compared to other risk scores, the HAS-BLED score was significantly better in predicting major bleeding events (Delong test, all P < 0.05, apart from mOBRI, HEMORR2HAGES) and ICH (all p < 0.05), and additionally, resulted in a net reclassification improvement (NRI) of 17.1-65.5% in predicting major bleeding events and 29.5-67.3% in predicting ICH (all p < 0.05). We conclude that the HAS-BLED score had the best predictive and discriminatory ability for major bleeding and ICH in an Asian/Chinese AF population. PMID:27557876

  12. Assessing bleeding risk in 4824 Asian patients with atrial fibrillation: The Beijing PLA Hospital Atrial Fibrillation Project

    PubMed Central

    Guo, Yu-tao; Zhang, Ye; Shi, Xiang-min; Shan, Zhao-liang; Wang, Chun-jiang; Wang, Yu-tang; Chen, Yun-dai; Lip, Gregory Y. H.

    2016-01-01

    The risks of major bleeding and intracranial hemorrhage (ICH) are higher in Asian patients with atrial fibrillation (AF) compared to non-Asians. We aimed to investigate risk factors for bleeding, and validate the predictive value of available bleeding risk scores (mOBRI, HEMORR2HAGES, Shireman, HAS-BLED, ATRIA and ORBIT) in a large cohort of Chinese inpatients with AF. Using hospital electronic medical databases, we identified 4824 AF patients (mean age 67 years; 34.9% female) from January 1, 1995 to May 30, 2015, with median (interquartile) in-hospital days of 10 (7–16) days. On multivariate analysis, prior bleeds, vascular disease, anemia, prior stroke, and liver dysfunction were independent risk factors of major bleeding (all p < 0.05). C-statistics (95%CI) of the HAS-BLED score were 0.72 (0.65–0.79) for major bleeding events and 0.83 (0.75–0.91) for ICH (all p < 0.001). Compared to other risk scores, the HAS-BLED score was significantly better in predicting major bleeding events (Delong test, all P < 0.05, apart from mOBRI, HEMORR2HAGES) and ICH (all p < 0.05), and additionally, resulted in a net reclassification improvement (NRI) of 17.1–65.5% in predicting major bleeding events and 29.5–67.3% in predicting ICH (all p < 0.05). We conclude that the HAS-BLED score had the best predictive and discriminatory ability for major bleeding and ICH in an Asian/Chinese AF population. PMID:27557876

  13. Dynamic approximate entropy electroanatomic maps detect rotors in a simulated atrial fibrillation model.

    PubMed

    Ugarte, Juan P; Orozco-Duque, Andrés; Tobón, Catalina; Kremen, Vaclav; Novak, Daniel; Saiz, Javier; Oesterlein, Tobias; Schmitt, Clauss; Luik, Armin; Bustamante, John

    2014-01-01

    There is evidence that rotors could be drivers that maintain atrial fibrillation. Complex fractionated atrial electrograms have been located in rotor tip areas. However, the concept of electrogram fractionation, defined using time intervals, is still controversial as a tool for locating target sites for ablation. We hypothesize that the fractionation phenomenon is better described using non-linear dynamic measures, such as approximate entropy, and that this tool could be used for locating the rotor tip. The aim of this work has been to determine the relationship between approximate entropy and fractionated electrograms, and to develop a new tool for rotor mapping based on fractionation levels. Two episodes of chronic atrial fibrillation were simulated in a 3D human atrial model, in which rotors were observed. Dynamic approximate entropy maps were calculated using unipolar electrogram signals generated over the whole surface of the 3D atrial model. In addition, we optimized the approximate entropy calculation using two real multi-center databases of fractionated electrogram signals, labeled in 4 levels of fractionation. We found that the values of approximate entropy and the levels of fractionation are positively correlated. This allows the dynamic approximate entropy maps to localize the tips from stable and meandering rotors. Furthermore, we assessed the optimized approximate entropy using bipolar electrograms generated over a vicinity enclosing a rotor, achieving rotor detection. Our results suggest that high approximate entropy values are able to detect a high level of fractionation and to locate rotor tips in simulated atrial fibrillation episodes. We suggest that dynamic approximate entropy maps could become a tool for atrial fibrillation rotor mapping.

  14. Optimization of Catheter Ablation of Atrial Fibrillation: Insights Gained from Clinically-Derived Computer Models

    PubMed Central

    Zhao, Jichao; Kharche, Sanjay R.; Hansen, Brian J.; Csepe, Thomas A.; Wang, Yufeng; Stiles, Martin K.; Fedorov, Vadim V.

    2015-01-01

    Atrial fibrillation (AF) is the most common heart rhythm disturbance, and its treatment is an increasing economic burden on the health care system. Despite recent intense clinical, experimental and basic research activity, the treatment of AF with current antiarrhythmic drugs and catheter/surgical therapies remains limited. Radiofrequency catheter ablation (RFCA) is widely used to treat patients with AF. Current clinical ablation strategies are largely based on atrial anatomy and/or substrate detected using different approaches, and they vary from one clinical center to another. The nature of clinical ablation leads to ambiguity regarding the optimal patient personalization of the therapy partly due to the fact that each empirical configuration of ablation lines made in a patient is irreversible during one ablation procedure. To investigate optimized ablation lesion line sets, in silico experimentation is an ideal solution. 3D computer models give us a unique advantage to plan and assess the effectiveness of different ablation strategies before and during RFCA. Reliability of in silico assessment is ensured by inclusion of accurate 3D atrial geometry, realistic fiber orientation, accurate fibrosis distribution and cellular kinetics; however, most of this detailed information in the current computer models is extrapolated from animal models and not from the human heart. The predictive power of computer models will increase as they are validated with human experimental and clinical data. To make the most from a computer model, one needs to develop 3D computer models based on the same functionally and structurally mapped intact human atria with high spatial resolution. The purpose of this review paper is to summarize recent developments in clinically-derived computer models and the clinical insights they provide for catheter ablation. PMID:25984605

  15. A roadmap to improve the quality of atrial fibrillation management: proceedings from the fifth Atrial Fibrillation Network/European Heart Rhythm Association consensus conference.

    PubMed

    Kirchhof, Paulus; Breithardt, Günter; Bax, Jeroen; Benninger, Gerlinde; Blomstrom-Lundqvist, Carina; Boriani, Giuseppe; Brandes, Axel; Brown, Helen; Brueckmann, Martina; Calkins, Hugh; Calvert, Melanie; Christoffels, Vincent; Crijns, Harry; Dobrev, Dobromir; Ellinor, Patrick; Fabritz, Larissa; Fetsch, Thomas; Freedman, S Ben; Gerth, Andrea; Goette, Andreas; Guasch, Eduard; Hack, Guido; Haegeli, Laurent; Hatem, Stephane; Haeusler, Karl Georg; Heidbüchel, Hein; Heinrich-Nols, Jutta; Hidden-Lucet, Francoise; Hindricks, Gerd; Juul-Möller, Steen; Kääb, Stefan; Kappenberger, Lukas; Kespohl, Stefanie; Kotecha, Dipak; Lane, Deirdre A; Leute, Angelika; Lewalter, Thorsten; Meyer, Ralf; Mont, Lluis; Münzel, Felix; Nabauer, Michael; Nielsen, Jens C; Oeff, Michael; Oldgren, Jonas; Oto, Ali; Piccini, Jonathan P; Pilmeyer, Art; Potpara, Tatjana; Ravens, Ursula; Reinecke, Holger; Rostock, Thomas; Rustige, Joerg; Savelieva, Irene; Schnabel, Renate; Schotten, Ulrich; Schwichtenberg, Lars; Sinner, Moritz F; Steinbeck, Gerhard; Stoll, Monika; Tavazzi, Luigi; Themistoclakis, Sakis; Tse, Hung Fat; Van Gelder, Isabelle C; Vardas, Panagiotis E; Varpula, Timo; Vincent, Alphons; Werring, David; Willems, Stephan; Ziegler, André; Lip, Gregory Y H; Camm, A John

    2016-01-01

    At least 30 million people worldwide carry a diagnosis of atrial fibrillation (AF), and many more suffer from undiagnosed, subclinical, or 'silent' AF. Atrial fibrillation-related cardiovascular mortality and morbidity, including cardiovascular deaths, heart failure, stroke, and hospitalizations, remain unacceptably high, even when evidence-based therapies such as anticoagulation and rate control are used. Furthermore, it is still necessary to define how best to prevent AF, largely due to a lack of clinical measures that would allow identification of treatable causes of AF in any given patient. Hence, there are important unmet clinical and research needs in the evaluation and management of AF patients. The ensuing needs and opportunities for improving the quality of AF care were discussed during the fifth Atrial Fibrillation Network/European Heart Rhythm Association consensus conference in Nice, France, on 22 and 23 January 2015. Here, we report the outcome of this conference, with a focus on (i) learning from our 'neighbours' to improve AF care, (ii) patient-centred approaches to AF management, (iii) structured care of AF patients, (iv) improving the quality of AF treatment, and (v) personalization of AF management. This report ends with a list of priorities for research in AF patients.

  16. A roadmap to improve the quality of atrial fibrillation management: proceedings from the fifth Atrial Fibrillation Network/European Heart Rhythm Association consensus conference.

    PubMed

    Kirchhof, Paulus; Breithardt, Günter; Bax, Jeroen; Benninger, Gerlinde; Blomstrom-Lundqvist, Carina; Boriani, Giuseppe; Brandes, Axel; Brown, Helen; Brueckmann, Martina; Calkins, Hugh; Calvert, Melanie; Christoffels, Vincent; Crijns, Harry; Dobrev, Dobromir; Ellinor, Patrick; Fabritz, Larissa; Fetsch, Thomas; Freedman, S Ben; Gerth, Andrea; Goette, Andreas; Guasch, Eduard; Hack, Guido; Haegeli, Laurent; Hatem, Stephane; Haeusler, Karl Georg; Heidbüchel, Hein; Heinrich-Nols, Jutta; Hidden-Lucet, Francoise; Hindricks, Gerd; Juul-Möller, Steen; Kääb, Stefan; Kappenberger, Lukas; Kespohl, Stefanie; Kotecha, Dipak; Lane, Deirdre A; Leute, Angelika; Lewalter, Thorsten; Meyer, Ralf; Mont, Lluis; Münzel, Felix; Nabauer, Michael; Nielsen, Jens C; Oeff, Michael; Oldgren, Jonas; Oto, Ali; Piccini, Jonathan P; Pilmeyer, Art; Potpara, Tatjana; Ravens, Ursula; Reinecke, Holger; Rostock, Thomas; Rustige, Joerg; Savelieva, Irene; Schnabel, Renate; Schotten, Ulrich; Schwichtenberg, Lars; Sinner, Moritz F; Steinbeck, Gerhard; Stoll, Monika; Tavazzi, Luigi; Themistoclakis, Sakis; Tse, Hung Fat; Van Gelder, Isabelle C; Vardas, Panagiotis E; Varpula, Timo; Vincent, Alphons; Werring, David; Willems, Stephan; Ziegler, André; Lip, Gregory Y H; Camm, A John

    2016-01-01

    At least 30 million people worldwide carry a diagnosis of atrial fibrillation (AF), and many more suffer from undiagnosed, subclinical, or 'silent' AF. Atrial fibrillation-related cardiovascular mortality and morbidity, including cardiovascular deaths, heart failure, stroke, and hospitalizations, remain unacceptably high, even when evidence-based therapies such as anticoagulation and rate control are used. Furthermore, it is still necessary to define how best to prevent AF, largely due to a lack of clinical measures that would allow identification of treatable causes of AF in any given patient. Hence, there are important unmet clinical and research needs in the evaluation and management of AF patients. The ensuing needs and opportunities for improving the quality of AF care were discussed during the fifth Atrial Fibrillation Network/European Heart Rhythm Association consensus conference in Nice, France, on 22 and 23 January 2015. Here, we report the outcome of this conference, with a focus on (i) learning from our 'neighbours' to improve AF care, (ii) patient-centred approaches to AF management, (iii) structured care of AF patients, (iv) improving the quality of AF treatment, and (v) personalization of AF management. This report ends with a list of priorities for research in AF patients. PMID:26481149

  17. Atrial Substrate Modification in Atrial Fibrillation: Targeting GP or CFAE? Evidence from Meta-Analysis of Clinical Trials

    PubMed Central

    Qin, Mu; Liu, Xu; Wu, Shao-Hui; Zhang, Xiao-Dong

    2016-01-01

    Several clinically relevant outcomes post atrial substrate modification in patients with atrial fibrillation (AF) have not been systematically analyzed among published studies on adjunctive cardiac ganglionated plexi (GP) or complex fractionated atrial electograms (CFAE) ablation vs. pulmonary vein isolation (PVI) alone. Out of 176 reports identified, the present meta-analysis included 14 randomized and non-randomized controlled trials (1613 patients) meeting inclusion criteria. Addition of GP ablation to PVI significantly increased freedom from atrial tachyarrhythmia in short- (OR: 1.72; P = 0.003) and long-term (OR: 2.0, P = 0.0006) follow-up, while adjunctive CFAE ablation did not after one or repeat procedure (P<0.05). The percentage of atrial tachycardia or atrial flutter (AT/AFL) after one procedure was higher for CFAE than GP ablation. In sub-analysis of non-paroxysmal AF, relative to PVI alone, adjunctive GP but not CFAE ablation significantly increased sinus rhythm maintenance (OR: 1.88, P = 0.01; and OR:1.24, P = 0.18, respectively). Meta regression analysis of the 14 studies indicated that sample size was significant source of heterogeneity either in outcomes after one or repeat procedure. In conclusion, in patients with AF, adjunctive GP but not CFAE ablation appeared to significantly add to the beneficial effects on sinus rhythm maintenance of PVI ablation alone; and CFAE ablation was associated with higher incidence of subsequent AT/AFL. PMID:27764185

  18. Ablation of left atrial flutter in a patient surgically treated for atrial fibrillation. Does it indicate a possible hybrid approach?

    PubMed

    Barbato, Gaetano; Marinelli, Giuseppe; Carinci, Valeria; Chiappini, Bruno; Pergolini, Francesco; Bracchetti, Daniele; Di Pasquale, Giuseppe

    2004-12-01

    Surgical treatment of atrial fibrillation (AF) has a high success rate and nowadays simpler and faster procedures have been proposed. The following is a description of the case of a patient who, after a modified Maze procedure, developed an atypical left atrial flutter and underwent a successful radiofrequency ablation procedure. A 71-year-old male underwent surgical biological valve replacement and a concomitant modified Maze procedure. After surgery the patient developed a persistent atrial arrhythmia with severe symptoms and refractory to any drug. For this reason, an electrophysiological study was planned. We performed a three-dimensional atrial mapping using the real-time position management system (Boston Scientific). Right atrial mapping indicated an early activation area on the septum. After transseptal puncture, left atrial mapping showed a reentry circuit around the mitral annulus with positive entrainment. A linear lesion was made between the mitral annulus and the superior right pulmonary vein and sinus rhythm was restored. After 7 months of follow-up the patient is asymptomatic and still in stable sinus rhythm. In conclusion, the follow-up of surgical AF may be improved by close collaboration between the surgeon and electrophysiologist. The available data suggest that a combined surgical and percutaneous approach could be the strategy of choice.

  19. Pulmonary vein isolation during atrial fibrillation using a circumferential cryoablation catheter.

    PubMed

    Rostock, Thomas; Weiss, Christian; Ventura, Rodolfo; Willems, Stephan

    2004-07-01

    Pulmonary vein (PV) isolation for the treatment of atrial fibrillation is limited by procedure related complications, such as PV stenosis and occlusions. We report about a PV isolation using a circumferential cryoablation catheter which applies the ablation energy simultaneously at the entire circumference by cooling down to a minimal temperature of -80 degrees C.

  20. The evolving role of stroke prediction schemes for patients with atrial fibrillation.

    PubMed

    Ha, Andrew; Healey, Jeff S

    2013-10-01

    Our approach to managing patients with atrial fibrillation has changed substantially over the past 10 years, as a result of numerous high-quality observation studies and randomized trials. In this article, we will provide practical guidance for the use of oral anticoagulation therapy in patients with atrial fibrillation. We will review the evolution of stroke and bleeding risk prediction schemes and discuss their role in patient care. Initially, stroke prediction schemes were used to identify patients with atrial fibrillation at the highest risk of stroke, in whom the use of oral anticoagulant therapy was believed to be the most important. However; with the advent of new, safer, and more convenient oral anticoagulant drugs, the role of these schemes has shifted to the identification of the lowest risk patients, representing the minority of patients with atrial fibrillation, in whom oral anticoagulant therapy is not recommended. At the same time, schemes were developed to predict bleeding, the major risk of oral anticoagulant therapy. However; use of these schemes has been limited by their complexity and significant correlation with stroke schemes. In general, it is advisable to base the decision to use oral anticoagulation on the patient's stroke risk and use bleeding schemes to identify absolute contraindications or modifiable risk factors for bleeding. Prediction schemes have been useful clinical tools, invaluable in the design of clinical trials, and have assisted greatly in economic analyses. However, the nature and role of such schemes is now adapting to the current era of novel oral anticoagulant agents.

  1. Atrial Fibrillation in Acute St-Elevation Myocardial Infarction: Clinical and Prognostic Features

    PubMed Central

    Gorenek, Bulent; Kudaiberdieva, Gulmira

    2012-01-01

    Atrial fibrillation (AF) is a common arrhythmia in the setting of acute coronary syndrome and acute ST-elevation myocardial infarction (STEMI). This review summarizes recent evidence on the clinical and prognostic significance of pre-existent and new-onset AF in acute STEMI patients and highlights new emerging predictors of AF development in the era of contemporary treatment. PMID:22920476

  2. A useful trick for difficult transseptal access during cryoballoon ablation for atrial fibrillation.

    PubMed

    Conte, Giulio; Chierchia, Gian-Battista; Brugada, Pedro

    2014-02-01

    A 76-year-old man with history of coronary artery bypass graft surgery was referred to our department for cryoballoon ablation of symptomatic drug-resistant paroxysmal atrial fibrillation. Thick septum can complicate such procedures; we describe a useful maneuver to circumvent this problem.

  3. Two Cases of Acute Renal Infarction in the Setting of Atrial Fibrillation

    PubMed Central

    Yousuf, Tariq; Ziffra, Jeffrey; Iqbal, Hina; Said, Albara; Oyama, Joseph H.; Lerma, Edgar V.; Chadaga, Amar R.

    2016-01-01

    Background: Acute renal infarction (ARI) is an uncommon and often overlooked diagnosis in patients presenting with acute kidney injury and abdominal pain. Case Reports: We present 2 cases of ARI in the setting of atrial fibrillation along with a review of medical literature pertaining to ARI. Conclusion: This article should aid clinicians in the diagnosis of ARI.

  4. Renal function in atrial fibrillation patients switched from warfarin to a direct oral anticoagulant.

    PubMed

    Minhas, Anum S; Jiang, Qingmei; Gu, Xiaokui; Haymart, Brian; Kline-Rogers, Eva; Almany, Steve; Kozlowski, Jay; Krol, Gregory D; Kaatz, Scott; Froehlich, James B; Barnes, Geoffrey D

    2016-11-01

    All available direct oral anticoagulants (DOACs) are at least partially eliminated by the kidneys. These agents are increasingly being used as alternatives to warfarin for stroke prevention in patients with atrial fibrillation. The aim of this study was to identify changes in renal function and associated DOAC dosing implications in a multicenter cohort of atrial fibrillation patients switched from warfarin to DOAC treatment. We included all patients in the Michigan Anticoagulation Quality Improvement Initiative cohort who switched from warfarin to a DOAC with atrial fibrillation as their anticoagulant indication between 2009 and 2014, and who had at least two creatinine values. Compliance with FDA-recommended dosing based on renal function was assessed. Of the 189 patients switched from warfarin to a DOAC, 34 (18.0 %) had a baseline creatinine clearance <50 mL/min and 23 (12.2 %) experienced important fluctuations in renal function. Of these 23 patients, 6 (26.1 %) should have impacted the DOAC dosing, but only 1 patient actually received an appropriate dose adjustment. Additionally, 15 (7.9 %) of patients on DOACs had a dose change performed, but only one patient demonstrated a change in renal function to justify the dose adjustment. Most atrial fibrillation patients who switched from warfarin to a DOAC had stable renal function. However, the majority of patients who had a change in renal function did not receive the indicated dose change. As the use of DOACs expands, monitoring of renal function and appropriate dose adjustments are critical.

  5. Comparative effects of carvedilol and amiodarone on conversion and recurrence rates of persistent atrial fibrillation.

    PubMed

    Kanoupakis, Emmanuel M; Manios, Emmanuel G; Mavrakis, Hercules E; Tzerakis, Panos G; Mouloudi, Helen K; Vardas, Panos E

    2004-09-01

    Pretreatment with antiarrhythmic agents could improve cardioversion and recurrence rates in patients with persistent atrial fibrillation. In a prospective controlled trial, 145 patients were randomly assigned to treatment with carvedilol, amiodarone, or placebo for 4 weeks before electrical cardioversion. Although the 2 drugs had similar effects on cardioversion rates, amiodarone was superior in terms of sinus rhythm maintenance after conversion.

  6. Case report: Atrial fibrillation following exposure to ambient air pollution particles

    EPA Science Inventory

    CONTEXT: Exposure to air pollution can result in the onset of atrial fibrillation. CASE PRESENTATION: We present a case of a 58 year old woman who volunteered to participate in a controlled exposure to concentrated ambient particles (CAPs). Twenty minutes into the exposure, there...

  7. Two Cases of Acute Renal Infarction in the Setting of Atrial Fibrillation

    PubMed Central

    Yousuf, Tariq; Ziffra, Jeffrey; Iqbal, Hina; Said, Albara; Oyama, Joseph H.; Lerma, Edgar V.; Chadaga, Amar R.

    2016-01-01

    Background: Acute renal infarction (ARI) is an uncommon and often overlooked diagnosis in patients presenting with acute kidney injury and abdominal pain. Case Reports: We present 2 cases of ARI in the setting of atrial fibrillation along with a review of medical literature pertaining to ARI. Conclusion: This article should aid clinicians in the diagnosis of ARI. PMID:27660583

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

    PubMed Central

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

    2014-01-01

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

  9. Nonvalvular atrial fibrillation: evidence for a prothrombotic state

    PubMed Central

    Kahn, S R; Solymoss, S; Flegel, K M

    1997-01-01

    OBJECTIVE: To determine whether patients with nonvalvular atrial fibrillation (NVAF) have prothrombotic changes compared with patients in sinus rhythm. DESIGN: Cross-sectional study. Hemostatic function compared in NVAF patients without prior embolic event (transient ischemic attack or embolic stroke) and control subjects without prior thrombotic stroke, and in NVAF patients with prior embolic event and control subjects with prior thrombotic stroke. SETTING: Internal medicine outpatient group practice and anticoagulation clinic in 2 teaching hospitals. PATIENTS: A total of 75 NVAF patients (50 without and 25 with prior embolic event) and 42 control patients (31 without and 11 with prior thrombotic stroke) recruited concurrently over 18 months during 1990-91. OUTCOME MEASURES: Platelet count, prothrombin time (PT), partial thromboplastin time (PTT), and plasma levels of hemoglobin, fibrinogen, von Willebrand factor antigen, factor VIII, fibrin D-dimer, antithrombin III, protein C, protein S, fibrinopeptide A and prothrombin fragment F1+2. All statistical analyses were performed after adjustments for age and sex. RESULTS: The NVAF patients without a prior embolic event had significantly higher mean hemoglobin and fibrinogen levels (p < 0.001 and p = 0.05, respectively) than the control subjects without prior thrombotic stroke. The 29 NVAF patients not taking warfarin (none had had an embolic event) had significantly lower mean protein C and protein S levels (p = 0.012 and p < 0.001, respectively) and a significantly higher fibrinopeptide A level (p = 0.03, after exclusion of outliers) than the control subjects without prior stroke. The NVAF patients with a prior embolic event had alterations in the hemostatic variables similar to those seen in the control patients with a prior thrombotic stroke. The latter had significantly higher fibrinogen, von Willebrand factor antigen and factor VIII levels (p = 0.04, 0.002 and 0.002, respectively) and significantly lower protein

  10. Atrial fibrillation detection using an iPhone 4S.

    PubMed

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

    2013-01-01

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

  11. The Role of Inflammation and Oxidative Stress in Atrial Fibrillation

    PubMed Central

    Li, Jie; Solus, Joseph; Chen, Qingxia; Rho, Young Hee; Milne, Ginger; Stein, C. Michael; Darbar, Dawood

    2010-01-01

    BACKGROUND Atrial fibrillation (AF) is the most common arrhythmia in clinical practice. There is increasing evidence that inflammation and oxidative stress contribute to the pathogenesis of AF, but their role remains poorly defined. Furthermore, it is unclear if inflammation and oxidative stress are associated with particular types of AF. OBJECTIVE The purpose of this study was to define the role of inflammation and oxidative stress in AF. METHODS Using a case-control study design, 305 patients with AF were compared to 150 control patients. AF was categorized into lone and typical AF, and further sub-categorized as paroxysmal, persistent or permanent AF. Serum concentrations of interleukin (IL)-6, IL-8, IL-10, tumor necrosis factor (TNF)-α, monocyte chemotactic protein (MCP)-1, vascular endothelial growth factor (VEGF) and N-terminal pro-brain natriuretic peptide (NTpBNP) and urinary F2-isoprostanes, a measure of oxidative stress, were measured. RESULTS IL-6, IL-8, IL-10, TNF-α, MCP1, VEGF and NTpBNP concentrations were independently associated with AF (all P values <0.05), but F2-isoprostane excretion was not elevated (P=0.50). There was a graded increase in TNF-α (median [interquartile range (IQR)]: 6.8 [3.4–11.3], 8.0 [5.6–10.9], 10.1 [5.7–12.4] pg/ml, P<0.05) and NTpBNP (170.6 [67.3–481.9], 681.39 [310.3–1439.0], 1179.9 [653.1–2096.0] pg/ml, P<0.001) among the subgroups of paroxysmal, persistent and permanent AF, respectively. CONCLUSIONS This study shows that inflammatory biomarkers were significantly increased in patients with AF, supporting a strong association between inflammation and the arrhythmia. Surprisingly, urinary F2-isoprostanes, a sensitive index of systemic oxidative stress in vivo, were not increased in AF overall, or in different subtypes of AF. PMID:20153266

  12. Management of atrial fibrillation: focus on the role of dronedarone

    PubMed Central

    Cheng, Judy WM

    2011-01-01

    Background: Dronedarone is an amiodarone derivative that was approved in the US in July 2009 to reduce the risk of cardiovascular hospitalization in patients with paroxysmal or persistent atrial fibrillation (AF), who are in sinus rhythm (SR), or who will be cardioverted. Objective: This article reviews the pharmacology, adverse effects, and clinical evidence available to date on the use of dronedarone in the management of AF and its potential role in the emergency department setting. Results: In the EURIDIS and ADONIS studies evaluating the efficacy of dronedarone in maintaining SR, dronedarone significantly reduced the risk of recurrence of AF compared to placebo, by 22% and 27%, respectively. The ERATO study examined the ability of dronedarone to control ventricular rate in permanent AF. The DIONYSOS study demonstrated that recurrences of AF were more frequent with dronedarone. However, discontinuation of therapy due to intolerance was more frequent with amiodarone. Furthermore, the ATHENA study demonstrated that dronedarone reduced mortality and cardiovascular hospitalization by 24% (P < 0.05) in patients in SR but with other associated risks and a history of AF. However, the ANDROMEDA study, evaluating the use of dronedarone in patients with recent decompensated heart failure, and the PALLAS study, evaluating the use of dronedarone in patients with chronic AF, were both terminated prematurely due to a trend toward an increased risk of cardiovascular events. Conclusion: Dronedarone has been demonstrated to be effective in reducing the incidence of AF recurrence. It appears to be less effective but better tolerated than amiodarone. Dronedarone appears to have a low proarrhythmic risk and is the first anti-arrhythmic that has been demonstrated to reduce cardiovascular mortality and cardiovascular hospitalization in clinically stable patients with other risk factors for recurrent AF. Therefore, dronedarone can be recommended as an anti-arrhythmic of choice in

  13. Assessment of left and right atrial 3D hemodynamics in patients with atrial fibrillation: a 4D flow MRI study.

    PubMed

    Markl, Michael; Carr, Maria; Ng, Jason; Lee, Daniel C; Jarvis, Kelly; Carr, James; Goldberger, Jeffrey J

    2016-05-01

    Atrial fibrillation (AF) is associated with embolic stroke due to thrombus formation in the left atrium (LA). Based on the relationship of atrial stasis to thromboembolism and the marked disparity in pulmonary versus systemic thromboembolism in AF, we tested the hypothesis that flow velocity distributions in the left (LA) versus right atrium (RA) in patients with would demonstrate increased stasis. Whole heart 4D flow MRI was performed in 62 AF patients (n = 33 in sinus rhythm during imaging, n = 29 with persistent AF) and 8 controls for the assessment of in vivo atrial 3D blood flow. 3D segmentation of the LA and RA geometry and normalized velocity histograms assessed atrial velocity distribution and stasis (% of atrial velocities <0.2 m/s). Atrial hemodynamics were similar for RA and LA and significantly correlated (mean velocity: r = 0.64; stasis: r = 0.55, p < 0.001). RA and LA mean and median velocities were lower in AF patients by 15-33 % and stasis was elevated by 11-19 % compared to controls. There was high inter-individual variability in LA/RA mean velocity ratio (range 0.5-1.8) and LA/RA stasis ratio (range 0.7-1.7). Patients with a history of AF and in sinus rhythm showed most pronounced differences in atrial flow (reduced mean velocities, higher stasis in the LA). While there is no systematic difference in LA versus RA flow velocity profiles, high variability was noted. Further delineation of patient specific factors and/or regional atrial effects on the LA and RA flow velocity profiles, as well as other factors such as differences in procoagulant factors, may explain the more prevalent systemic versus pulmonary thromboembolism in patients with AF. PMID:26820740

  14. Role of Calcium-activated Potassium Channels in Atrial Fibrillation Pathophysiology and Therapy.

    PubMed

    Diness, Jonas G; Bentzen, Bo H; Sørensen, Ulrik S; Grunnet, Morten

    2015-11-01

    Small-conductance Ca(2+)-activated potassium (SK) channels are relative newcomers within the field of cardiac electrophysiology. In recent years, an increased focus has been given to these channels because they might constitute a relatively atrial-selective target. This review will give a general introduction to SK channels followed by their proposed function in the heart under normal and pathophysiological conditions. It is revealed how antiarrhythmic effects can be obtained by SK channel inhibition in a number of species in situations of atrial fibrillation. On the contrary, the beneficial effects of SK channel inhibition in situations of heart failure are questionable and still needs investigation. The understanding of cardiac SK channels is rapidly increasing these years, and it is hoped that this will clarify whether SK channel inhibition has potential as a new anti-atrial fibrillation principle. PMID:25830485

  15. Role of Calcium-activated Potassium Channels in Atrial Fibrillation Pathophysiology and Therapy.

    PubMed

    Diness, Jonas G; Bentzen, Bo H; Sørensen, Ulrik S; Grunnet, Morten

    2015-11-01

    Small-conductance Ca(2+)-activated potassium (SK) channels are relative newcomers within the field of cardiac electrophysiology. In recent years, an increased focus has been given to these channels because they might constitute a relatively atrial-selective target. This review will give a general introduction to SK channels followed by their proposed function in the heart under normal and pathophysiological conditions. It is revealed how antiarrhythmic effects can be obtained by SK channel inhibition in a number of species in situations of atrial fibrillation. On the contrary, the beneficial effects of SK channel inhibition in situations of heart failure are questionable and still needs investigation. The understanding of cardiac SK channels is rapidly increasing these years, and it is hoped that this will clarify whether SK channel inhibition has potential as a new anti-atrial fibrillation principle.

  16. Incidence, Predictors, and Impact of Postoperative Atrial Fibrillation after Coronary Artery Bypass Grafting in Military Veterans

    PubMed Central

    Cornwell, Lorraine D.; Bakshi, Ankur; Rachlin, Eric; Preventza, Ourania; Rosengart, Todd K.; Coselli, Joseph S.; LeMaire, Scott A.; Petersen, Nancy J.; Pattakos, Greg; Bakaeen, Faisal G.

    2016-01-01

    Little is known about the frequency and clinical implications of postoperative atrial fibrillation in military veterans who undergo coronary artery bypass grafting (CABG). We examined long-term survival data, clinical outcomes, and associated risk factors in this population. We retrospectively reviewed baseline, intraoperative, and postoperative data from 1,248 consecutive patients with similar baseline risk profiles who underwent primary isolated CABG at a Veterans Affairs hospital from October 2006 through March 2013. Multivariable logistic regression identified predictors of postoperative atrial fibrillation. Kaplan-Meier analysis was used to evaluate long-term survival (the primary outcome measure), morbidity, and length of hospital stay. Postoperative atrial fibrillation occurred in 215 patients (17.2%). Independent predictors of this sequela were age ≥65 years (odds ratios [95% confidence intervals], 1.7 [1.3–2.4] for patients of age 65–75 yr and 2.6 [1.4–4.8] for patients >75 yr) and body mass index ≥30 kg/m2 (2.0 [1.2–3.2]). Length of stay was longer for patients with postoperative atrial fibrillation than for those without (12.7 ± 6.6 vs 10.3 ± 8.9 d; P ≤0.0001), and the respective 30-day mortality rate was higher (1.9% vs 0.4%; P=0.014). Seven-year survival rates did not differ significantly. Older and obese patients are particularly at risk of postoperative atrial fibrillation after CABG. Patients who develop the sequela have longer hospital stays than, but similar long-term survival rates to, patients who do not. PMID:27777519

  17. A mutation in the atrial-specific myosin light chain gene (MYL4) causes familial atrial fibrillation

    PubMed Central

    Orr, Nathan; Arnaout, Rima; Gula, Lorne J.; Spears, Danna A.; Leong-Sit, Peter; Li, Qiuju; Tarhuni, Wadea; Reischauer, Sven; Chauhan, Vijay S.; Borkovich, Matthew; Uppal, Shaheen; Adler, Arnon; Coughlin, Shaun R.; Stainier, Didier Y. R.; Gollob, Michael H.

    2016-01-01

    Atrial fibrillation (AF), the most common arrhythmia, is a growing epidemic with substantial morbidity and economic burden. Mechanisms underlying vulnerability to AF remain poorly understood, which contributes to the current lack of highly effective therapies. Recognizing mechanistic subtypes of AF may guide an individualized approach to patient management. Here, we describe a family with a previously unreported syndrome characterized by early-onset AF (age <35 years), conduction disease and signs of a primary atrial myopathy. Phenotypic penetrance was complete in all mutation carriers, although complete disease expressivity appears to be age-dependent. We show that this syndrome is caused by a novel, heterozygous p.Glu11Lys mutation in the atrial-specific myosin light chain gene MYL4. In zebrafish, mutant MYL4 leads to disruption of sarcomeric structure, atrial enlargement and electrical abnormalities associated with human AF. These findings describe the cause of a rare subtype of AF due to a primary, atrial-specific sarcomeric defect. PMID:27066836

  18. Simultaneously Presented Acute Ischemic Stroke and Non-ST Elevation Myocardial Infarction in a Patient with Paroxysmal Atrial Fibrillation

    PubMed Central

    Kim, Hack-Lyoung; Seo, Jae-Bin; Chung, Woo-Young; Zo, Joo-Hee; Kim, Myung-A

    2013-01-01

    Although atrial fibrillation is the most frequent cause of embolic stroke, coronary embolism from atrial fibrillation is a very rare cause of acute myocardial infarction. Therefore, simultaneously presented acute ischemic stroke and acute myocardial infarction due to atrial fibrillation in the same patient has not been documented. The present report describes the case of a 58-year-old man with paroxysmal atrial fibrillation who initially presented with a large cerebral infarction due to embolic occlusion of the left middle cerebral artery. Four hours after the diagnosis of cerebral embolism, he was subsequently diagnosed with acute myocardial infarction due to concurrent coronary embolism. He underwent successful coronary revascularization with a drug-eluting stent. The possibility of combined coronary embolism as a rare etiology should be kept in mind when a patient with acute embolic stroke presents, especially when there is evidence of acute myocardial infarction. PMID:24363753

  19. [Should we add antiplatelet therapy to oral anticoagulation in patients with atrial fibrillation and vascular disease? Review of available evidence].

    PubMed

    Andreu, José Manuel; Roldán, Vanessa; García-Navarro, Miguel; Ruipérez, Juan Antonio; Valdés, Mariano; Marín, Francisco

    2012-01-01

    Current recommendation is to add antiplatelet drug to oral anticoagulation in patients with atrial fibrillation (AF) and vascular disease. However, it is debatable to join both antithrombotic drugs in stable vascular disease.

  20. Sex differences in the treatment of patients with atrial fibrillation: population-based study in a local health district.

    PubMed

    Riesgo, Alba; Sant, Elisenda; Benito, Luisa; Hoyo, Jordi; Miró, Oscar; Mont, Lluís; Bragulat, Ernest; Coll-Vinent, Blanca

    2011-03-01

    Differences in the treatment of atrial fibrillation between men and women were investigated by using patients in a local health district as a reference population. The study included 688 patients (359 female) who presented with atrial fibrillation. Women were older, more frequently had heart failure, and were more often functionally dependent than men. With regards to the management of atrial fibrillation, women were prescribed digoxin more frequently than men, but underwent electrical cardioversion less often, were less frequently seen by a cardiologist, and understood less about their treatment. After stratifying the findings by age and adjusting for heart failure and the degree of functional dependence, it was observed that women aged over 85 years were prescribed digoxin more often than men, while women aged under 65 years underwent cardioversion less often than men. In conclusion, gender differences observed in the treatment of atrial fibrillation cannot be fully explained by differences in clinical characteristics between men and women in the population.

  1. Phosphodiesterase4D (PDE4D)--A risk factor for atrial fibrillation and stroke?

    PubMed

    Jørgensen, Carina; Yasmeen, Saiqa; Iversen, Helle K; Kruuse, Christina

    2015-12-15

    Mutations in the gene encoding phosphodiesterase 4D (PDE4D) enzyme are associated with ischemic stroke; however the functional implications of such mutations are not well understood. PDE4D is part of a complex protein family modulating intracellular signalling by cyclic nucleotides. The PDE4 family includes subtypes A-D, all of which show unique intracellular, cellular and tissue distribution. PDE4D is the major subtype expressed in human atrial myocytes and involved in the pathophysiology of arrhythmias, such as atrial fibrillation. The PDE4D enzyme hydrolyses cyclic adenosine monophosphate (cAMP). Though diverging results are reported, several population based studies describe association of various PDE4D single nucleotide polymorphisms (SNP) with cardio-embolic stroke in particular. Functionally, a down regulation of PDE4D variants has been reported in stroke patients. The anti-inflammatory and vasodilator properties of PDE4 inhibitors make them suitable for treatment of stroke and cardiovascular disease. PDE4D has recently been suggested as factor in atrial fibrillation. This review summarizes the possible function of PDE4D in the brain, heart, and vasculature. Further, association of the described SNPs, in particular, with cardioembolic stroke, is reviewed. Current findings on the PDE4D mutations suggest functionality involves an increased cardiac risk factor as well as augmented risk of atrial fibrillation. PMID:26671126

  2. New implantable therapeutic device for the control of an atrial fibrillation attack using the Peltier element.

    PubMed

    Yambe, Tomoyuki; Sumiyoshi, Taketada; Koga, Chihiro; Shiraishi, Yasuyuki; Miura, Hidekazu; Sugita, Norihiro; Tanaka, Akira; Yoshizawa, Makoto

    2012-01-01

    For the development of the new therapeutic device for the atrial fibrillation, implantable cooling device using Peltier element was developed in this study. An implantable cooling device had been consisted from Peltier element with transcutaneous energy transmission system (TETS). 1st coil can be contacted from outside of the body, when the patients will feel palpitation. Electrical current will be induced to the implanted 2nd coil. Peltier element will able to cool the surface of the atrium. For the confirmation of the effect of the cooling device, trial manufacture model was developed. Animal experiments using six healthy adult goats after animal ethical committee allowance was carried out. Fourth intercostals space had been opened after anesthesia inhalation, and various sensors had been inserted. AF was induced by the electrical current with battery. As the results, AF had been recovered to the normal sinus rhythm after cooling in all six goats. So, this cooling system for the control of AF showed evident effect in these experiments. Smaller size cooling device has been under development aiming at totally implantable type. Catheter type cooling device for the insertion by the use of fiber-scope type is now under planning for the clinical application. This new type device may be able to become good news for the patients with uncontrollable AF. PMID:23367233

  3. Twenty-eight day Holter monitoring is poorly tolerated and insensitive for paroxysmal atrial fibrillation detection in cryptogenic stroke.

    PubMed

    Tu, H T; Spence, S; Kalman, J M; Davis, S M

    2014-05-01

    This pilot study in a prospective cohort of 20 cryptogenic stroke patients showed that a significant proportion has paroxysmal atrial fibrillation undetected by 24-h Holter monitoring. However, longer monitoring with 28-day Holter was poorly tolerated and still insufficiently sensitive for paroxysmal atrial fibrillation detection. Further studies are urgently needed to elucidate the optimal timing, method and duration of cardiac rhythm monitoring following ischaemic stroke.

  4. Paroxysmal Atrial Fibrillation and Brain Freeze: A Case of Recurrent Co-Incident Precipitation From a Frozen Beverage

    PubMed Central

    Lugovskaya, Nelya; Vinson, David R.

    2016-01-01

    Patient: Male, 29 Final Diagnosis: Paroxysmal atrial fibrillation • cold-stimulus headache Symptoms: Palpitations • headache Medication: Diltiazem • Ibutilide Clinical Procedure: None Specialty: Emergency Medicine • Internal Medicine Objective: Unknown ethiology • Rare disease Background: Episodes of paroxysmal atrial fibrillation may be precipitated by the rapid ingestion of ice-cold foods and beverages. This condition has received little research attention, and its true prevalence is poorly described. Treating physicians may not identify cold ingestion as a causal factor of paroxysmal atrial fibrillation, thus compromising both history taking and patient education. Case Report: We report a case of a healthy young-adult man who drank a slushed ice beverage that immediately induced atrial fibrillation and a brain freeze headache simultaneously. This occurred on two separate occasions, years apart. During both episodes, the acute brain freeze self-resolved quickly, but the new-onset palpitations occasioned a visit to the emergency department for diagnosis and treatment. The emergency physicians failed to make the causal link between the cold drink and the atrial dysrhythmia. Though the brain freeze headache and paroxysmal atrial fibrillation were both precipitated by rapid ingestion of an ice-cold beverage, the mediating mechanisms are distinct. We review these two cold-induced conditions, their prevalence, and their probable mechanisms. Conclusions: The recurrent simultaneous occurrence of brain-freeze headache with paroxysmal atrial fibrillation identifies the ingestion of a frozen beverage as the precipitant of the atrial dysrhythmia. Increasing physician awareness of cold ingestion as a cause of paroxysmal atrial fibrillation will improve history taking and patient education. PMID:26757615

  5. The effect of internal DC shocks on the atrial fibrillation frequency.

    PubMed

    Diaz, J; Castro, N; Escalona, O; Anderson, J McC; Glover, B M; Adgey, J A

    2007-01-01

    The objective of this study, was to investigate the effect of internal DC shocks on the atrial fibrillation frequency (AFF). AFF has previously been shown to predict the success and energy requirements in patients undergoing internal cardioversion (IC) of atrial fibrillation (AF). However the possibility that unsuccessful shocks during IC may influence the AFF has not been before studied. Thirty eight patients with AF, suggested for DC cardioversion at the Royal Victoria Hospital in Belfast, were included in our study. Two catheters were positioned in the right atrial appendage (RAA) and the coronary sinus (CS), to deliver a biphasic shock waveform, synchronized with the R wave of the electrocardiogram (ECG) signal. A voltage step-up protocol (50-300 V) was used for patient cardioversion. The ECG was analyzed for a mean of 52,8+/-10.1 seconds (corresponding to segments before and after nonsuccessful shocks). Atrial fibrillatory activity was extracted by means of bandpass filtering and ventricular activity (QRST) cancellation. QRST complexes were cancelled using a recursive least squared (RLS) adaptive filter. FFT was applied to the residual atrial fibrillatory signal. AFF was estimated from the dominant frequency within the 3-12 Hz band of the power spectrum. R-R intervals during the segments were also analyzed. A total of 26 patients were successfully cardioverted, employing 167 shocks (141 nonsuccessful). AFF, computed with 10 s of signal, showed significant reduction (mean 0.3052 +/- 1.1055 Hz, P=0.028) comparing segments immediately before and after shocks, and AFF significantly increases (mean 0.2582 +/- 0.609 Hz, P=0.007) between segments immediately after shocks and those 35 s after. AFF showed distinct behavior according to the energy level of the shocks. In conclusion, intracardiac electric shocks could cause transitory changes in the AFF of patients with atrial fibrillation.

  6. Examining warfarin underutilization rates in patients with atrial fibrillation: Detailed chart review essential to capture contraindications to warfarin therapy

    PubMed Central

    Srivastava, Ajay; Hudson, Michael; Hamoud, Ihab; Cavalcante, Joao; Pai, Chetan; Kaatz, Scott

    2008-01-01

    Introduction Atrial fibrillation affects an estimated 2.5 million Americans and incurs an average annual stroke risk of 4.5% per year. Despite warfarin reducing stroke risk by approximately 66%, prior studies show warfarin usage rates to be about 50%. However, the methods that define warfarin as "inappropriate underutilization" might not be sensitive enough to pick up relative contraindications. We assessed the inappropriate underutilization of warfarin in atrial fibrillation patients at our hospital by abstracting individual patient charts. Methods Medical records were reviewed to determine stroke risk factors, warfarin use, and documented contraindications to warfarin use in 364 consecutive patients with atrial fibrillation. Results Amongst 364 atrial fibrillation patients, 54.6% received warfarin anticoagulation. Overall, 29.5 % of patients had documented reasons for not prescribing warfarin. Primary reasons listed by treating physicians included: gastrointestinal bleed 10.7%, secondary/transient atrial fibrillation 8.2%, and fall risk 6.3%. Only 7.1% of the patients had no documented reasons for the lack of warfarin use. Conclusion Consistent with previous reports, 45.4% of patients in this atrial fibrillation cohort were not prescribed warfarin. However, after reviewing medical charts for documented reasons why warfarin was not used, the inappropriate underutilization rate was only 7.1%. These findings suggest that studies utilizing administrative database and ICD-9 CM coding might overestimate warfarin underutilization. PMID:18522741

  7. Mechanisms of termination and prevention of atrial fibrillation by drug therapy.

    PubMed

    Workman, A J; Smith, G L; Rankin, A C

    2011-08-01

    Atrial fibrillation (AF) is a disorder of the rhythm of electrical activation of the cardiac atria. It is the most common cardiac arrhythmia, has multiple aetiologies, and increases the risk of death from stroke. Pharmacological therapy is the mainstay of treatment for AF, but currently available anti-arrhythmic drugs have limited efficacy and safety. An improved understanding of how anti-arrhythmic drugs affect the electrophysiological mechanisms of AF initiation and maintenance, in the setting of the different cardiac diseases that predispose to AF, is therefore required. A variety of animal models of AF has been developed, to represent and control the pathophysiological causes and risk factors of AF, and to permit the measurement of detailed and invasive parameters relating to the associated electrophysiological mechanisms of AF. The purpose of this review is to examine, consolidate and compare available relevant data on in-vivo electrophysiological mechanisms of AF suppression by currently approved and investigational anti-arrhythmic drugs in such models. These include the Vaughan Williams class I-IV drugs, namely Na(+) channel blockers, β-adrenoceptor antagonists, action potential prolonging drugs, and Ca(2+) channel blockers; the "upstream therapies", e.g., angiotensin converting enzyme inhibitors, statins and fish oils; and a variety of investigational drugs such as "atrial-selective" multiple ion channel blockers, gap junction-enhancers, and intracellular Ca(2+)-handling modulators. It is hoped that this will help to clarify the main electrophysiological mechanisms of action of different and related drug types in different disease settings, and the likely clinical significance and potential future exploitation of such mechanisms.

  8. Mechanisms of termination and prevention of atrial fibrillation by drug therapy

    PubMed Central

    Workman, AJ; Smith, GL; Rankin, AC

    2011-01-01

    Atrial fibrillation (AF) is a disorder of the rhythm of electrical activation of the cardiac atria. It is the most common cardiac arrhythmia, has multiple aetiologies, and increases the risk of death from stroke. Pharmacological therapy is the mainstay of treatment for AF, but currently available anti-arrhythmic drugs have limited efficacy and safety. An improved understanding of how anti-arrhythmic drugs affect the electrophysiological mechanisms of AF initiation and maintenance, in the setting of the different cardiac diseases that predispose to AF, is therefore required. A variety of animal models of AF has been developed, to represent and control the pathophysiological causes and risk factors of AF, and to permit the measurement of detailed and invasive parameters relating to the associated electrophysiological mechanisms of AF. The purpose of this review is to examine, consolidate and compare available relevant data on in-vivo electrophysiological mechanisms of AF suppression by currently approved and investigational anti-arrhythmic drugs in such models. These include the Vaughan Williams class I-IV drugs, namely Na+ channel blockers, β-adrenoceptor antagonists, action potential prolonging drugs, and Ca2+ channel blockers; the “upstream therapies”, e.g., angiotensin converting enzyme inhibitors, statins and fish oils; and a variety of investigational drugs such as “atrial-selective” multiple ion channel blockers, gap junction-enhancers, and intracellular Ca2+-handling modulators. It is hoped that this will help to clarify the main electrophysiological mechanisms of action of different and related drug types in different disease settings, and the likely clinical significance and potential future exploitation of such mechanisms. PMID:21334377

  9. Managing atrial fibrillation in the very elderly patient: challenges and solutions

    PubMed Central

    Karamichalakis, Nikolaos; Letsas, Konstantinos P; Vlachos, Konstantinos; Georgopoulos, Stamatis; Bakalakos, Athanasios; Efremidis, Michael; Sideris, Antonios

    2015-01-01

    Atrial fibrillation (AF) is the most common arrhythmia affecting elderly patients. Management and treatment of AF in this rapidly growing population of older patients involve a comprehensive assessment that includes comorbidities, functional, and social status. The cornerstone in therapy of AF is thromboembolic protection. Anticoagulation therapy has evolved, using conventional or newer medications. Percutaneous left atrial appendage closure is a new invasive procedure evolving as an alternative to systematic anticoagulation therapy. Rate or rhythm control leads to relief in symptoms, fewer hospitalizations, and an improvement in quality of life. Invasive methods, such as catheter ablation, are the new frontier of treatment in maintaining an even sinus rhythm in this particular population. PMID:26604772

  10. Anticoagulant and Antiplatelet Therapy in Patients with Atrial Fibrillation and Coronary Artery Disease

    PubMed Central

    Mischke, Karl; Knackstedt, Christian; Marx, Nikolaus

    2012-01-01

    Anticoagulation represents the mainstay of therapy for most patients with atrial fibrillation. Patients on oral anticoagulation often require concomitant antiplatelet therapy, mostly because of coronary artery disease. After coronary stent implantation, dual antiplatelet therapy is necessary. However, the combination of oral anticoagulation and antiplatelet therapy increases the bleeding risk. Risk scores such as the CHA2DS2-Vasc score and the HAS-BLED score help to identify both bleeding and stroke risk in individual patients. The guidelines of the European Society of Cardiology provide a rather detailed recommendation for patients on oral anticoagulation after coronary stent implantation. However, robust evidence is lacking for some of the recommendations, and especially for new oral anticoagulants and new antiplatelets few or no data are available. This review addresses some of the critical points of the guidelines and discusses potential advantages of new anticoagulants in patients with atrial fibrillation after stent implantation. PMID:22577538

  11. Electrocution-induced atrial fibrillation: a novel cause of a familiar arrhythmia.

    PubMed

    Langford, Alex; Dayer, Mark

    2012-04-04

    A previously fit and well 40-year-old man presented to the emergency department with palpitations after suffering an 11 000 volt electrical shock from overhead power cables through a mobile crane which he was operating. His ECG demonstrated the presence of new atrial fibrillation at a rate of 80 beats per min. He was haemodynamically stable, and had otherwise only sustained a small exit burn to his left great toe. Routine blood tests including creatine kinase and troponin T were normal. A bolus of intravenous flecainide failed to restore sinus rhythm, but an amiodarone infusion was successful. An electrical shock is a rare cause of atrial fibrillation. There is no consensus over optimal medical management. Numerous treatment plans have been previously employed with varying degrees of success.

  12. Déjà vu in the theories of atrial fibrillation dynamics

    PubMed Central

    Jalife, José

    2011-01-01

    This brief review looks back to the major theoretical, experimental, and clinical work on the dynamics and mechanisms of atrial fibrillation (AF). Its goal is to highlight the most important issues, controversies, and advances that have driven the field of investigation into AF mechanisms at any given time during the last ∼100 years. It emphasizes that while the history of AF research has been full of controversies from the start, such controversies have led to new information, and individual scientists have learned from those that have preceded them. However, in the face of the most common sustained cardiac arrhythmia seen in clinical practice, we are yet to fully understand its fundamental mechanisms and learn how to treat it effectively. Future research into AF dynamics and mechanisms should focus on the development and validation of new numerical and animal models. Such models should be relevant to and accurately reproduce the important substrates associated with ageing and with diseases such as hypertension, heart failure, and ischaemic heart disease which cause AF in the vast majority of patients. Knowledge derived from such models may help to greatly advance the field and hopefully lead to more effective prevention and therapy. PMID:21097807

  13. [ANALYSIS OF ARACHIDONIC ACID RELATIVE CONTENT CHANGES IN ERYTHROCYTES AND PLATELETS PHOSPHOLIPIDS MEMBRANES FEATURES IN CORONARY HEART DISEASE WITH ATRIAL FIBRILLATION PATIENTS].

    PubMed

    Lizogub, V G; Zavalska, T V; Merkulova, I O; Bryuzgina, T S

    2015-01-01

    Erythrocytes and platelets phospholipid membranes fatty acid spectrum was detected in coronary heart disease and atrial fibrillation patients and in patients with coronary heart disease without atrial fibrillation. 87 patients were investigated. Significant decrease in the arachidonic acid relative content in coronary heart disease patients compared with healthy individuals was related. As well as a significant decrease in the arachidonic acid relative content in coronary heart disease and atrial fibrillation patients compared with coronary heart disease patients without atrial fibrillation was related too. These dates may indicate that decreasing relative content arachidonic acid can be possible pathogenetic link in the development of arrhythmias.

  14. Warfarin and atrial fibrillation: from ideal to real the warfarin affaire

    PubMed Central

    2014-01-01

    Vitamin K Antagonists (VKAs) are widely used in clinical practice and nearly 1% of the entire population receives oral anticoagulation at least once in life. However, the rate of prescription of anticoagulation is low, compared to what it should be. No more than 50-60% of patients affected by atrial fibrillation (AF) receive anticoagulation. In the setting of AF, VKAs are safe and effective when properly managed, reducing stroke and systemic embolism by more than 60%. VKAs safety and effectiveness are closely related to the quality of anticoagulation (e.g. time in therapeutic range), and anticoagulation clinics offer the best management of anticoagulant therapy. However, a sizeable proportion of patients are managed elsewhere. In clinical practice, in the setting of AF, a low prescription rate of VKAs is frequently observed and this is due also to difficulties in managing laboratory monitoring and drug dose adjustment. The suboptimal management of therapy with VKAs leads to a lesser efficacy than that reported in clinical trials, and to an increase in adverse reactions. VKAs still remain the first and only available therapy for a number of diseases (e.g. valvular atrial fibrillation and mechanical prosthetic heart valves). Now, since approval of the new oral anticoagulants (NOAs), the choice of anticoagulant therapy in definite settings, such as stroke prevention in non-valvular atrial fibrillation (SPAF) or treatment of venous thromboembolism, has surely become more intriguing but also more problematic. In light of these new therapeutic options, we reviewed VKAs therapy, in the setting of atrial fibrillation, focusing on VKAs impact in real life. We analyzed the data about efficacy and safety of warfarin at three levels: clinical trial and real life, outside and inside anticoagulation clinics. PMID:24548437

  15. Chronic atrial fibrillation in presence of aortic stenosis in a patient with polysplenia syndrome.

    PubMed

    Bronte, E; Trovato, Rl; Di Miceli, R; Sucato, V; Candela, P; Brancatelli, G; Novo, S

    2013-01-01

    We report a rare case of "situs viscerum ambiguous" with polysplenia syndrome, in a 69 year old female patient with aortic stenosis and chronic atrial fibrillation. The presenting symptom was dyspnoea on moderate exertion and an ECG showed supra ventricular arrhythmia. Patients trans-thoracic echocardiogram revealed a dilated left atrium, reduced ejection fraction, mild tricuspid regurgitation, moderate-severe pulmonary hypertension and severe aortic stenosis. The patient was successfully treated with a replacement of her aortic valve and ascending aorta.

  16. Contraindications to Anticoagulation Therapy and Eligibility for Novel Anticoagulants in Older Patients With Atrial Fibrillation

    PubMed Central

    Steinberg, Benjamin A.; Greiner, Melissa A.; Hammill, Bradley G.; Curtis, Lesley H.; Benjamin, Emelia J.; Heckbert, Susan R.; Piccini, Jonathan P.

    2015-01-01

    Aims Oral anticoagulation therapy prevents stroke and improves survival in patients with atrial fibrillation, but the therapy is underutilized. We sought to identify the prevalence of contraindications for oral anticoagulation and the proportion of patients potentially eligible for different agents. Methods We identified patients with nonacute atrial fibrillation in a nationally representative 5% sample of 2009 Medicare data. We divided the population into patients ineligible for any oral anticoagulant, patients eligible for warfarin only, and patients eligible for any anticoagulant. We compared patient characteristics and the use of anticoagulation among the subgroups. Results Among 86,671 patients with atrial fibrillation, 1872 (2.2%) were ineligible for anticoagulation because of an absolute contraindication, most frequently a history of intracranial hemorrhage (60%). Patients ineligible for any anticoagulant were the same age as the overall group (mean age, 80.5 vs 80.4 years). However, they had higher rates of dementia (19% vs 8.6%) and heart failure (59% vs 43%) and higher mean CHADS2 scores (3.8 vs 2.8). Of the remaining 84,799 patients eligible for anticoagulation, 7146 (8.4%) had were eligible for warfarin only (most commonly because of mechanical heart valves [66%] and end-stage renal disease [12%]). Sixty-five percent of patients eligible for anticoagulation received warfarin, and the proportion was similar for patients with a relatively high risk of bleeding. Conclusions Older adults with atrial fibrillation rarely have absolute contraindications to oral anticoagulation therapy. Among patients without contraindications, most appeared to be eligible for any anticoagulant, and relatively high-risk features appeared not to influence warfarin use. PMID:25930214

  17. Prolonged atrial fibrillation precipitated by new-onset seizures and marijuana abuse.

    PubMed

    Singh, Dinesh; Huntwork, Margaret; Shetty, Varun; Sequeira, Gina; Akingbola, Olugbenga

    2014-02-01

    We report a case of prolonged atrial fibrillation (AF) precipitated by new-onset generalized tonic-clonic convulsions and marijuana abuse in a developmentally normal 18-year-old adolescent with a structurally normal heart. Our case highlights an interesting association and a unique pathophysiology between generalized tonic-clonic convulsions, marijuana abuse, and AF. We suggest that seizures and marijuana abuse should be considered in the differential diagnosis of the etiology of AF in children. PMID:24420812

  18. New oral anticoagulants: their role in stroke prevention in high-risk patients with atrial fibrillation.

    PubMed

    Ferns, Sunita J; Naccarelli, Gerald V

    2015-07-01

    Based on efficacy, safety, and ease of use, novel oral anticoagulants will likely replace VKAs for many if not most patients with atrial fibrillation. Novel anticoagulants have a lower rate of intracranial hemorrhage compared with vitamin K antagonists. The incidence of other life-threatening bleeds is similar if not lower. Dose adjustments need to be made based on renal function and advanced age. There is at present a need for an antidote for these new drugs.

  19. Natriuretic Peptides as Predictors of Atrial Fibrillation Recurrences Following Electrical Cardioversion.

    PubMed

    Zografos, Theodoros A; Katritsis, Demosthenes G

    2013-11-01

    Electrical cardioversion (ECV) can be effective in restoring sinus rhythm (SR) in the majority of patients with atrial fibrillation (AF). Several factors that predispose to AF recurrences, such as age, AF duration and left atrial size have been used to guide a decision for cardioversion, but increasing evidence suggests that they may be rather poor markers of left atrial structural remodeling that determines the long-term success of a rhythm control strategy. In this context, the use of easily obtainable biomarkers, such as the levels of atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP), to predict AF recurrences may be preferable. Since ANP production is associated with the extent of functional atrial myocardium, and both ANP and BNP reflect atrial pressure and mechanical stretching, these peptides are good candidate biomarkers to assess predisposition to AF recurrences. In this review we focus on the pathophysiological mechanisms and the available clinical evidence regarding the prediction of AF recurrences following successful ECV from pre-procedural ANP and BNP levels.

  20. Natriuretic Peptides as Predictors of Atrial Fibrillation Recurrences Following Electrical Cardioversion

    PubMed Central

    Zografos, Theodoros A; Katritsis, Demosthenes G

    2013-01-01

    Electrical cardioversion (ECV) can be effective in restoring sinus rhythm (SR) in the majority of patients with atrial fibrillation (AF). Several factors that predispose to AF recurrences, such as age, AF duration and left atrial size have been used to guide a decision for cardioversion, but increasing evidence suggests that they may be rather poor markers of left atrial structural remodeling that determines the long-term success of a rhythm control strategy. In this context, the use of easily obtainable biomarkers, such as the levels of atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP), to predict AF recurrences may be preferable. Since ANP production is associated with the extent of functional atrial myocardium, and both ANP and BNP reflect atrial pressure and mechanical stretching, these peptides are good candidate biomarkers to assess predisposition to AF recurrences. In this review we focus on the pathophysiological mechanisms and the available clinical evidence regarding the prediction of AF recurrences following successful ECV from pre-procedural ANP and BNP levels. PMID:26835050

  1. Long-term biatrial recordings in post-operative atrial fibrillation.

    PubMed

    Masè, M; Graffigna, A; Sinelli, S; Pallaoro, G; Nollo, G; Ravelli, F

    2010-01-01

    Although atrial fibrillation (AF) is a common complication of cardiac surgery, its pathophysiology remains unclear. The study of post-operative AF demands for the recording of cardiac electrical activity in correspondence of AF onset and progression. Long-term recordings in post-surgery patients could provide this information, but, to date, have been limited to surface signals, which precludes a characterization of the arrhythmic triggers and substrate. In this study we demonstrate the feasibility of a continuous long-term recording of atrial electrical activities from the right and left atria in post-surgery patients. Local atrial epicardial electrograms are acquired by positioning temporary pacing wires in the right and left atria at the end of the intervention, while three day recordings are obtained by a digital holter recorder, adapted to epicardial signal features. The capability of the system to map local atrial activity and the possibility to obtain quantitative information on atrial rate and synchronization from the processed epicardial signals are proven in representative examples. The quantitative description of local atrial properties opens new perspective in the investigation of post-surgery AF.

  2. Mathematical Approaches to Understanding and Imaging Atrial Fibrillation: Significance for Mechanisms and Management

    PubMed Central

    Trayanova, Natalia A

    2014-01-01

    Atrial fibrillation (AF) is the most common sustained arrhythmia in humans. The mechanisms that govern AF initiation and persistence are highly complex, of dynamic nature, and involve interactions across multiple temporal and spatial scales in the atria. This articles aims to review the mathematical modeling and computer simulation approaches to understanding AF mechanisms and aiding in its management. Various atrial modeling approaches are presented, with descriptions of the methodological basis and advancements in both lower-dimensional and realistic geometry models. A review of the most significant mechanistic insights made by atrial simulations is provided. The article showcases the contributions that atrial modeling and simulation have made not only to our understanding of the pathophysiology of atrial arrhythmias, but also to the development of AF management approaches. A summary of the future developments envisioned for the field of atrial simulation and modeling is also presented. The review contends that computational models of the atria assembled with data from clinical imaging modalities that incorporate electrophysiological and structural remodeling could become a first line of screening for new AF therapies and approaches, new diagnostic developments, and new methods for arrhythmia prevention. PMID:24763468

  3. Role of the Autonomic Nervous System in Atrial Fibrillation: Pathophysiology and Therapy

    PubMed Central

    Chen, Peng-Sheng; Chen, Lan S.; Fishbein, Michael C.; Lin, Shien-Fong; Nattel, Stanley

    2014-01-01

    Autonomic nervous system activation can induce significant and heterogeneous changes of atrial electrophysiology and induce atrial tachyarrhythmias, including atrial tachycardia (AT) and atrial fibrillation (AF). The importance of the autonomic nervous system in atrial arrhythmogenesis is also supported by circadian variation in the incidence of symptomatic AF in humans. Methods that reduce autonomic innervation or outflow have been shown to reduce the incidence of spontaneous or induced atrial arrhythmias, suggesting that neuromodulation may be helpful in controlling AF. In this review we focus on the relationship between the autonomic nervous system and the pathophysiology of AF, and the potential benefit and limitations of neuromodulation in the management of this arrhythmia. We conclude that autonomic nerve activity plays an important role in the initiation and maintenance of AF, and modulating autonomic nerve function may contribute to AF control. Potential therapeutic applications include ganglionated plexus ablation, renal sympathetic denervation, cervical vagal nerve stimulation, baroreflex stimulation, cutaneous stimulation, novel drug approaches and biological therapies. While the role of the autonomic nervous system has long been recognized, new science and new technologies promise exciting prospects for the future. PMID:24763467

  4. Relationship between plasma level of vitamin D and post operative atrial fibrillation in patients undergoing CABG

    PubMed Central

    Shadvar, Kamran; Ramezani, Fariba; Sanaie, Sarvin; Maleki, Taher Entezari; Arbat, Babak Kazemi; Nagipour, Bahman

    2016-01-01

    Objective: Atrial fibrillation is the most common arrhythmia after cardiac surgery. Several studies have shown the impact of vitamin D on heart disease; however, there have been few studies for the incidence of AF and its relationship with vitamin D levels. According to the different results of these studies, we decided to evaluate the relation of plasma levels of vitamin D and postoperative atrial fibrillation in patients undergoing coronary artery bypass surgery (CABG). Methods: This cross-sectional study was performed on 50 patients after CABG surgery. Simple random sampling was done. Twenty five patients who developed AF within 48 hours after CABG with Cardiopulmonary bypass (CPB) were enrolled in the case group and 25 patients who did not develop AF within 48 hours after CABG with CPB were enrolled in the control group. Plasma levels of vitamin D in both groups of patients were recorded. Collected data were analyzed by the SPSS software version 17. Results: There was no significant difference in terms of demographic characteristics, comorbidities, lipid profile and kidney function between two groups. The mean plasma level of vitamin D was 27.4 ± 2.22 ng/ml in the case group and was 28.2 ± 1.18 ng/ml in the control group it (p= 0.803). Conclusions: Plasma levels of vitamin D were almost the same in both groups and there was no statistically significant difference between the groups with and without atrial fibrillation following CABG.

  5. Atrial fibrillation and flutter following coronary artery bypass graft surgery: A retrospective study and review

    PubMed Central

    Premaratne, Ishani D; Fernando, Naomi D; Williams, Lashira; Hasaniya, Nahidh W

    2016-01-01

    Introduction and objectives Atrial fibrillation is a common arrhythmia following coronary artery bypass graft surgery. Its incidence can range from 10 to 60% of patients undergoing coronary artery bypass graft. This rhythm can result in shorter or longer intervals between beats. Methods Medical records of 143 patients from the Queen’s Medical Center, Kuakini Medical Center, Saint Francis Medical Center, and Straub Hospital and Clinic, all of which are located in Honolulu, Hawaii were reviewed. An additional 39 records of patients who did not develop these complications were also reviewed as a control group. Patients were selected according to the ICD codes for atrial fibrillation/flutter and coronary artery bypass graft. Both anomalies can lead to increased health care costs, morbidity, and mortality. In this study, possible predisposing factors to these complications were investigated. The time of onset, weight gain, elapsed time, fluid status (in/out), hematocrit, and drug regimens were compared between the two groups. Results The differences in weight gain, fluid status, and hematocrit between the groups were not significant. There were a total of 17 different drugs prescribed to the group as a whole but not every patient received the same regimen. Conclusions Atrial fibrillation and flutter were found to be more common in males, particularly between the ages of 60 and 69 years. There were no other significant findings. PMID:27123238

  6. Use of Anticoagulant Warfarin in Patients Presenting With Atrial Fibrillation in a Tertiary Level Hospital.

    PubMed

    Islam, M S; Islam, M A; Azad, A K; Banerjee, S K; Ahmed, C M; Haque, H; Ahmed, M K; Rumki, R S; Mahmood, M; Rashid, F B

    2016-07-01

    Atrial fibrillation (AF) is the most common sustained arrhythmia in the World, occurring in approximately 0.4% of the general population. The purpose of the present study was to see the trend of use of warfarin in hospital admitted patients with atrial fibrillation. It was conducted in the department of cardiology, University Cardiac Centre, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh from January 2008 to January 2009. A total of 150 patients with atrial fibrillation were enrolled in this study. Out of them, male were 60(40%) and female 90(60%); age range 22-79 years. Most common presenting symptoms were palpitation (80%) & dyspnoea (70%). Chronic rheumatic heart disease (Mitral stenosis) (33%) was found in most cases followed by IHD (22%), hypertension (21%). According to CHADS₂ score, most of the patients belonged to moderate risk group (47%) and 32% in low risk group. Anticoagulation with warfarin was used in 40% cases of valvular AF & 25% patients with non valvular AF. Among non valvular AF, it was prescribed for 38% in high risk group, 34% in moderate risk & 3% in low risk group. The study states that warfarin is underused in both valvular & non valvular AF. PMID:27612901

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

    PubMed

    ElMaghawry, Mohamed

    2015-01-01

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

  8. Evaluation of patients' attitudes towards stroke prevention and bleeding risk in atrial fibrillation.

    PubMed

    Lahaye, S; Regpala, S; Lacombe, S; Sharma, M; Gibbens, S; Ball, D; Francis, K

    2014-03-01

    Patient's values and preferences regarding the relative importance of preventing strokes and avoiding bleeding are now recognised to be of great importance in deciding on therapy for the prevention of stroke due to atrial fibrillation (SPAF). We used an iPad questionnaire to determine the minimal clinically important difference (Treatment Threshold) and the maximum number of major bleeding events that a patient would be willing to endure in order to prevent one stroke (Bleeding Ratio) for the initiation of antithrombotic therapy in 172 hospital in-patients with documented non-valvular atrial fibrillation in whom anticoagulant therapy was being considered. Patients expressed strong opinions regarding SPAF. We found that 12% of patients were "medication averse" and were not willing to consider antithrombotic therapy; even if it was 100% effective in preventing strokes. Of those patients who were willing to consider antithrombotic therapy, 42% were identified as "risk averse" and 15% were "risk tolerant". Patients required at least a 0.8% (NNT=125) annual absolute risk reduction and 15% relative risk reduction in the risk of stroke in order to agree to initiate antithrombotic therapy, and patients were willing to endure 4.4 major bleeds in order to prevent one stroke. In conclusion, there was a substantial amount of inter-patient variability, and often extreme differences in opinion regarding tolerance of bleeding risk in the context of stroke prevention in atrial fibrillation. These findings highlight the importance of considering patient preferences when deciding on SPAF therapy.

  9. Relationship between plasma level of vitamin D and post operative atrial fibrillation in patients undergoing CABG

    PubMed Central

    Shadvar, Kamran; Ramezani, Fariba; Sanaie, Sarvin; Maleki, Taher Entezari; Arbat, Babak Kazemi; Nagipour, Bahman

    2016-01-01

    Objective: Atrial fibrillation is the most common arrhythmia after cardiac surgery. Several studies have shown the impact of vitamin D on heart disease; however, there have been few studies for the incidence of AF and its relationship with vitamin D levels. According to the different results of these studies, we decided to evaluate the relation of plasma levels of vitamin D and postoperative atrial fibrillation in patients undergoing coronary artery bypass surgery (CABG). Methods: This cross-sectional study was performed on 50 patients after CABG surgery. Simple random sampling was done. Twenty five patients who developed AF within 48 hours after CABG with Cardiopulmonary bypass (CPB) were enrolled in the case group and 25 patients who did not develop AF within 48 hours after CABG with CPB were enrolled in the control group. Plasma levels of vitamin D in both groups of patients were recorded. Collected data were analyzed by the SPSS software version 17. Results: There was no significant difference in terms of demographic characteristics, comorbidities, lipid profile and kidney function between two groups. The mean plasma level of vitamin D was 27.4 ± 2.22 ng/ml in the case group and was 28.2 ± 1.18 ng/ml in the control group it (p= 0.803). Conclusions: Plasma levels of vitamin D were almost the same in both groups and there was no statistically significant difference between the groups with and without atrial fibrillation following CABG. PMID:27648036

  10. The developing pulmonary veins and left atrium: implications for ablation strategy for atrial fibrillation.

    PubMed

    Sherif, Hisham M F

    2013-11-01

    The majority of cases of atrial fibrillation (AF) are the result of triggers originating in the area of the pulmonary veins. The reason for the predilection for that area remains unclear. We sought to examine the different mechanisms responsible for this observation through an extensive search of the medical literature, examining the development of the pulmonary veins, genetics of AF and left to -right cardiac chamber differentiation. Results confirm that the LAA is anatomically and embryologically different from other areas of the atrial walls and develops under distinct genetic and transcriptional pathways. Findings support an ablation strategy whose primary focus should be the creation of a 'box' lesion set, plus additional lines to prevent propagation to the left atrial appendage, the isthmus of the left atrium and the right atrium are likely to be more effective than simple pulmonary vein isolation.

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

    PubMed Central

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

    2012-01-01

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

  12. Atrial fibrillation disorganization is reduced by catheter ablation: a standard ECG study.

    PubMed

    Bonizzi, Pietro; Meste, Olivier; Zarzoso, Vicente; Latcu, Decebal Gabriel; Popescu, Irina; Ricard, Philippe; Saoudi, Nadir

    2010-01-01

    Selection of candidates to catheter ablation (CA) of long-lasting persistent atrial fibrillation (AF) is challenging, since success is not guaranteed. In this study, we put forward an automated method for noninvasively evaluating the reduction of the complexity of the AF organization following CA. Complexity is meant as the amount of disorganization observed on the ECG, supposed to be directly correlated to the number and interactions of atrial wavefronts. By means of PCA, the complexity of the AF organization is evaluated quantitatively from a 12-lead ECG recording. Preliminary results show that CA is able to reduce the complexity of AF organization in the atrial wavefront pattern propagation, despite the persistence of AF in most cases. This can be viewed as a first clinical validation of this parameter. Whether AF complexity and its reduction by CA are predictive of long-term outcome is thus still to be determined.

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

    PubMed

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

    2015-01-01

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

  14. The European Network for Translational Research in Atrial Fibrillation (EUTRAF): objectives and initial results.

    PubMed

    Schotten, Ulrich; Hatem, Stephane; Ravens, Ursula; Jaïs, Pierre; Müller, Frank-Ulrich; Goette, Andres; Rohr, Stephan; Antoons, Gudrun; Pieske, Burkert; Scherr, Daniel; Oto, Ali; Casadei, Barbara; Verheule, Sander; Cartlidge, David; Steinmeyer, Klaus; Götsche, Thorsten; Dobrev, Dobromir; Kockskämper, Jens; Lendeckel, Uwe; Fabritz, Larissa; Kirchhof, Paulus; Camm, A John

    2015-10-01

    Atrial fibrillation (AF) is the most common sustained arrhythmia in the general population. As an age-related arrhythmia AF is becoming a huge socio-economic burden for European healthcare systems. Despite significant progress in our understanding of the pathophysiology of AF, therapeutic strategies for AF have not changed substantially and the major challenges in the management of AF are still unmet. This lack of progress may be related to the multifactorial pathogenesis of atrial remodelling and AF that hampers the identification of causative pathophysiological alterations in individual patients. Also, again new mechanisms have been identified and the relative contribution of these mechanisms still has to be established. In November 2010, the European Union launched the large collaborative project EUTRAF (European Network of Translational Research in Atrial Fibrillation) to address these challenges. The main aims of EUTRAF are to study the main mechanisms of initiation and perpetuation of AF, to identify the molecular alterations underlying atrial remodelling, to develop markers allowing to monitor this processes, and suggest strategies to treat AF based on insights in newly defined disease mechanisms. This article reports on the objectives, the structure, and initial results of this network. PMID:26364316

  15. Atrial fibrillation: relation between clinical risk factors and transoesophageal echocardiographic risk factors for thromboembolism

    PubMed Central

    Illien, S; Maroto-Järvinen, S; von der Recke, G; Hammerstingl, C; Schmidt, H; Kuntz-Hehner, S; Lüderitz, B; Omran, H

    2003-01-01

    Objective: To correlate clinical risk factors for thromboembolism with transoesophageal echocardiography (TOE) markers of a thrombogenic milieu. Design: Clinical risk factors for thromboembolism and TOE markers of a thrombogenic milieu were assessed in consecutive patients with non-rheumatic atrial fibrillation. The following TOE parameters were assessed: presence of spontaneous echo contrast, thrombi, and left atrial appendage blood flow velocities. A history of hypertension, diabetes mellitus, or thromboembolic events, patient age > 65 years, and chronic heart failure were considered to be clinical risk factors for thromboembolism. Setting: Tertiary cardiac care centre. Patients: 301 consecutive patients with non-rheumatic atrial fibrillation scheduled for TOE. Results: 255 patients presented with clinical risk factors. 158 patients had reduced left atrial blood flow velocities, dense spontaneous echo contrast, or both. Logistic regression analysis showed that a reduced left ventricular ejection fraction and age > 65 years were the only independent predictors of a thrombogenic milieu (both p < 0.0001). The probability of having a thrombogenic milieu increased with the number of clinical risk factors present (p < 0.0001). 17.4% of the patients without clinical risk factors had a thrombogenic milieu whereas 41.2% of the patients presenting one or more clinical risk factors had none. Conclusion: There is a close relation between clinical risk factors and TOE markers of a thrombogenic milieu. In addition, TOE examination allows for the identification of patients with a thrombogenic milieu without clinical risk factors. PMID:12527668

  16. Atrial Mechanical Function Before and After Electrical or Amiodarone Cardioversion in Atrial Fibrillation: Assessment by Transesophageal Echocardiography and Pulsed Doppler.

    PubMed

    Maria Amuchastegui, Luis; Cravero, Cecilia; Salomone, Oscar; Amuchastegui, Marcos

    1996-03-01

    In some patients with atrial fibrillation (AF), it has been suggested that left atrial mechanical dysfunction can develop after successful electrical cardioversion, justifying postcardioversion anticoagulant treatment. The purpose of this study was to investigate differences in left atrial appendage peak flow velocities and the incidence of left atrial spontaneous echo contrast in patients with AF before and after electrical cardioversion or intravenous amiodarone, studied using transesophageal echocardiography (TEE) and pulsed Doppler. We performed a control TEE in 7 patients in the electrical group and 6 in the amiodarone group, with no significant clinical differences between both groups. A second TEE was performed immediately in the 7 patients with successful electrical cardioversion. The peak flow velocities in the appendage before and after the procedure were: filling 43.3 +/- 22 vs 27.7 +/- 28 cm/sec (P = 0.01) and emptying 35.5 +/- 22 vs 23.6 +/- 17 cm/sec (P = 0.01), respectively. The spontaneous echo contrast increased in 4 of the 7 patients. In 4 patients of the amiodarone group, the peak flow velocities in the appendage during AF and within the first 24 hours after restoration of sinus rhythm were: filling 37.4 +/- 12 vs 37.8 +/- 18 cm/sec and emptying 36.4 +/- 18 vs 35.9 +/- 18 cm/sec, respectively (P = NS). There was no change in spontaneous echo contrast. In conclusion, patients with AF reverted to sinus rhythm using amiodarone did not show changes in left atrial mechanical function; however, patients with electrical cardioversion showed mechanical dysfunction. Further investigations on the effects of amiodarone and other drugs on the mechanical function of the atria are needed to determine if patients reverted pharmacologically require anticoagulation post reversion. (ECHOCARDIOGRAPHY, Volume 13, March 1996)

  17. Cost effectiveness of left atrial appendage closure with the Watchman device for atrial fibrillation patients with absolute contraindications to warfarin

    PubMed Central

    Reddy, Vivek Y.; Akehurst, Ronald L.; Armstrong, Shannon O.; Amorosi, Stacey L.; Brereton, Nic; Hertz, Deanna S.; Holmes, David R.

    2016-01-01

    Aims Atrial fibrillation (AF) patients with contraindications to oral anticoagulation have had few options for stroke prevention. Recently, a novel oral anticoagulant, apixaban, and percutaneous left atrial appendage closure (LAAC) have emerged as safe and effective therapies for stroke risk reduction in these patients. This analysis assessed the cost effectiveness of LAAC with the Watchman device relative to apixaban and aspirin therapy in patients with non-valvular AF and contraindications to warfarin therapy. Methods and results A cost-effectiveness model was constructed using data from three studies on stroke prevention in patients with contraindications: the ASAP study evaluating the Watchman device, the ACTIVE A trial of aspirin and clopidogrel, and the AVERROES trial evaluating apixaban. The cost-effectiveness analysis was conducted from a German healthcare payer perspective over a 20-year time horizon. Left atrial appendage closure yielded more quality-adjusted life years (QALYs) than aspirin and apixaban by 2 and 4 years, respectively. At 5 years, LAAC was cost effective compared with aspirin with an incremental cost-effectiveness ratio (ICER) of €16 971. Left atrial appendage closure was cost effective compared with apixaban at 7 years with an ICER of €9040. Left atrial appendage closure was cost saving and more effective than aspirin and apixaban at 8 years and remained so throughout the 20-year time horizon. Conclusions This analysis demonstrates that LAAC with the Watchman device is a cost-effective and cost-saving solution for stroke risk reduction in patients with non-valvular AF who are at risk for stroke but have contraindications to warfarin. PMID:26838691

  18. β1-Adrenergic and M2 Muscarinic Autoantibodies and Thyroid Hormone Facilitate Induction of Atrial Fibrillation in Male Rabbits.

    PubMed

    Li, Hongliang; Murphy, Taylor; Zhang, Ling; Huang, Bing; Veitla, Vineet; Scherlag, Benjamin J; Kem, David C; Yu, Xichun

    2016-01-01

    Activating autoantibodies to the β1-adrenergic and M2 muscarinic receptors are present in a very high percentage of patients with Graves' disease and atrial fibrillation (AF). The objective of this study was to develop a reproducible animal model and thereby to examine the impact of these endocrine-like autoantibodies alone and with thyroid hormone on induction of thyroid-associated atrial tachyarrhythmias. Five New Zealand white rabbits were coimmunized with peptides from the second extracellular loops of the β1-adrenergic and M2 muscarinic receptors to produce both sympathomimetic and parasympathomimetic antibodies. A catheter-based electrophysiological study was performed on anesthetized rabbits before and after immunization and subsequent treatment with thyroid hormone. Antibody expression facilitated the induction of sustained sinus, junctional and atrial tachycardias, but not AF. Addition of excessive thyroid hormone resulted in induced sustained AF in all animals. AF induction was blocked acutely by the neutralization of these antibodies with immunogenic peptides despite continued hyperthyroidism. The measured atrial effective refractory period as one parameter of AF propensity shortened significantly after immunization and was acutely reversed by peptide neutralization. No further decrease in the effective refractory period was observed after the addition of thyroid hormone, suggesting other cardiac effects of thyroid hormone may contribute to its role in AF induction. This study demonstrates autonomic autoantibodies and thyroid hormone potentiate the vulnerability of the heart to AF, which can be reversed by decoy peptide therapy. These data help fulfill Witebsky's postulates for an increased autoimmune/endocrine basis for Graves' hyperthyroidism and AF. PMID:26517045

  19. Treatment of lone atrial fibrillation: minimally invasive pulmonary vein isolation, partial cardiac denervation and excision of the left atrial appendage

    PubMed Central

    2014-01-01

    Since 1999, my colleagues and I have diligently pursued a minimally invasive surgical, beating-heart, left atrial isolation technique that is offered to patients with lone atrial fibrillation (AF). We began clinical cases in 2003. In 2005, we reported our initial experience with video-assisted bilateral pulmonary vein (PV) isolation and left atrial appendage (LAA) exclusion for the minimally invasive treatment of AF (Wolf technique). From our experience in over 1,000 cases there have been many lessons learned in the evaluation, selection and minimally invasive surgical treatment of patients with lone AF. In our experience we have had zero mortality and no conversions to sternotomy. Recently we reviewed 157 patients who are now 1 to 9 years out from the Wolf technique. The patients’ ages ranged from 15 to 87 years old. The AF-free rate for paroxysmal AF was 92%, for persistent AF 85%, and for long-standing persistent AF 75%. The follow-up included 7-day continuous monitoring. There were no deaths (personal review). The Wolf technique is a safe and effective treatment for selected patients with lone AF. PMID:24516806

  20. Intensity of Left Atrial Spontaneous Echo Contrast as a Correlate for Stroke Risk Stratification in Patients with Nonvalvular Atrial Fibrillation

    PubMed Central

    Zhao, Yuanping; Ji, Lijing; Liu, Jian; Wu, Juefei; Wang, Yan; Shen, Shuxin; Guo, Shengcun; Jian, Rong; Chen, Gangbin; Wei, Xuan; Liao, Wangjun; Kutty, Shelby; Liao, Yulin; Bin, Jianping

    2016-01-01

    The intensity of left atrial spontaneous echo contrast (LASEC) by transesophageal echocardiography (TEE) has been proposed as an important variable in the stratification of thromboembolic risk, particularly in patients with nonvalvular atrial fibrillation (NVAF). We hypothesized that the quantification of LASEC by ultrasound will improve its utility in predicting subsequent stroke events in patients with NVAF. Patients (n = 206) with definite NVAF receiving TEE were included for this prospective cohort study. Baseline clinical risk factors of stroke, CHADS2 score and CHA2DS2-Vasc, left atrial thrombus (LAT), the five-grades of LASEC and video intensity (VI) value of LASEC were measured. During 2 years follow-up, 20 patients (9.7%) developed stroke. VI value of LASEC in the patients with stroke was higher compared to patients without stroke (25.30 ± 3.61 vs. 8.65 ± 0.81, p < 0.001). On logistic regression analysis, LAT, qualitative LASEC, graded LASEC, VI value of LASEC and CHADS2 and CHA2DS2-Vasc score were independent predictors of stroke. Among them, the highest area under the curve of receiver operating characteristic (ROC) in predicting stroke was VI value of LASEC (p < 0.05). These results show that quantification of LASEC by VI value is the most favorable predictor of stroke in patients with NVAF, and calls for improving the utility of LASEC in predicting subsequent stroke events. PMID:27277939

  1. Macro-reentrant atrial tachycardia conducting through a left superior vena cava after catheter ablation in a patient with paroxysmal atrial fibrillation.

    PubMed

    Kurotobi, Toshiya; Kino, Naoto; Tonomura, Daisuke; Shimada, Yoshihisa

    2015-01-01

    A left superior vena cava can be a cause of cardiac rhythm or conduction abnormalities, and can also be the arrhythmogenic source of atrial fibrillation (AF) with connections to the coronary sinus and left atrium. In the present study, we report a case with a macro re-entrant atrial tachycardia that coursed through the left superior vena cava after a previous AF ablation, which successfully ablated paroxysmal AF.

  2. Arrhythmias, elicited by catecholamines and serotonin, vanish in human chronic atrial fibrillation.

    PubMed

    Christ, Torsten; Rozmaritsa, Nadiia; Engel, Andreas; Berk, Emanuel; Knaut, Michael; Metzner, Katharina; Canteras, Manuel; Ravens, Ursula; Kaumann, Alberto

    2014-07-29

    Atrial fibrillation (AF) is the most common heart rhythm disorder. Transient postoperative AF can be elicited by high sympathetic nervous system activity. Catecholamines and serotonin cause arrhythmias in atrial trabeculae from patients with sinus rhythm (SR), but whether these arrhythmias occur in patients with chronic AF is unknown. We compared the incidence of arrhythmic contractions caused by norepinephrine, epinephrine, serotonin, and forskolin in atrial trabeculae from patients with SR and patients with AF. In the patients with AF, arrhythmias were markedly reduced for the agonists and abolished for forskolin, whereas maximum inotropic responses were markedly blunted only for serotonin. Serotonin and forskolin produced spontaneous diastolic Ca(2+) releases in atrial myocytes from the patients with SR that were abolished or reduced in myocytes from the patients with AF. For matching L-type Ca(2+)-current (ICa,L) responses, serotonin required and produced ∼ 100-fold less cAMP/PKA at the Ca(2+) channel domain compared with the catecholamines and forskolin. Norepinephrine-evoked ICa,L responses were decreased by inhibition of Ca(2+)/calmodulin-dependent kinase II (CaMKII) in myocytes from patients with SR, but not in those from patients with AF. Agonist-evoked phosphorylation by CaMKII at phospholamban (Thr-17), but not of ryanodine2 (Ser-2814), was reduced in trabeculae from patients with AF. The decreased CaMKII activity may contribute to the blunting of agonist-evoked arrhythmias in the atrial myocardium of patients with AF. PMID:25024212

  3. Serum Galectin-3 Levels Predict Recurrences after Ablation of Atrial Fibrillation

    PubMed Central

    Clementy, Nicolas; Benhenda, Nazih; Piver, Eric; Pierre, Bertrand; Bernard, Anne; Fauchier, Laurent; Pages, Jean-Christophe; Babuty, Dominique

    2016-01-01

    Galectin-3 is a biomarker of fibrosis and atrial remodeling, involved in the mechanisms of initiation and maintenance of atrial fibrillation (AF). We sought to study the accuracy of galectin-3 level in predicting recurrences of AF after ablation. Serum concentrations of galectin-3 were determined in a consecutive series of patients addressed for AF ablation in our center. After a 3-month blanking period, recurrences of atrial arrhythmias were collected during the first year in all patients, using Holter monitoring at 3, 6 months and 12 months. A total of 160 patients were included, with a mean galectin-3 rate was 14.4 ± 5.6 ng/mL. At 12-month, 55 patients (34%) had reexperienced sustained atrial arrhythmia. Only higher galectin-3 level (HR = 1.07 [1.01–1.12], p = 0.02) and larger left atrial diameter (HR = 1.07 [1.03–1.12], p = 0.001) independently predicted recurrence. Patients with both galectin-3 level <15 ng/mL and left atrial diameter <40 millimeters had a 1-year arrhythmia-free survival rate − after a single procedure without anti-arrhythmic drug − of 91%, as compared with 41% in patients with galectin-3 ≥ 15 and left trial diameter ≥40 (p < 0.0001), whether AF was paroxysmal or persistent. Galectin-3 and left atrial diameters, rather than clinical presentation of AF, predict recurrences after ablation. PMID:27677964

  4. Epidemiology of atrial fibrillation in France: extrapolation of international epidemiological data to France and analysis of French hospitalization data.

    PubMed

    Charlemagne, Agnès; Blacher, Jacques; Cohen, Ariel; Collet, Jean-Philippe; Diévart, François; de Groote, Pascal; Hanon, Olivier; Leenhardt, Antoine; Pinel, Jean-François; Pisica-Donose, George; Le Heuzey, Jean-Yves

    2011-02-01

    The prevalence of atrial fibrillation is steadily increasing throughout the world because of ageing populations and better management of coronary heart disease. An international literature review was conducted to estimate the prevalence and incidence of atrial fibrillation in France. A review of the literature on comorbidities was also performed. Finally, French mortality and hospitalization data were analysed using the PMSI database. The prevalence of atrial fibrillation is estimated to be between 600,000 and 1 million people; of these, two-thirds are aged >75 years. The incidence is estimated at between 110,000 and 230,000 new cases per year. In 2008, 412,000 hospitalized patients had a diagnosis of atrial fibrillation; this figure increased by 26% in the 3-year period between 2005 and 2008. These findings highlight the importance of targeting therapy, of upstream therapy, and of therapy that provides clear clinical and economic advantages over the well-established reductions already achieved in atrial fibrillation morbidity, mortality and cost. In addition, new prevention strategies should be developed, particularly secondary prevention strategies in patients with cardiovascular diseases. PMID:21402346

  5. NOX4-Dependent Hydrogen Peroxide Overproduction in Human Atrial Fibrillation and HL-1 Atrial Cells: Relationship to Hypertension

    PubMed Central

    Zhang, Jun; Youn, Ji Youn; Kim, Antony Y.; Ramirez, Rafael J.; Gao, Ling; Ngo, Doan; Chen, Peng; Scovotti, Jennifer; Mahajan, Aman; Cai, Hua

    2012-01-01

    Background/Objectives: Atrial fibrillation (AF) is the most common type of cardiac arrhythmia with patients dying frequently of stroke. In view of the unclear etiologies of AF and a potential role of oxidative stress, the present study examined cardiac reactive oxygen species production and NADPH oxidase (NOX) expression in AF patients. Methods and Results: Patients with AF were older than those without (58.8 ± 11.7 vs. 47.8 ± 19.2, p = 0.047). Whereas total O2∙- production (determined by electron spin resonance) was similar in patients with and without AF, H2O2 production was more than doubled in AF patients (149.8 ± 26.28 vs. 66.9 ± 7.14 pmol/mg/min, p = 0.0055), which correlated well with a doubling in NOX isoform 4 (NOX4) expression. AF patients with co-existing hypertension had three-fold higher H2O2 production compared to those without (239.0 ± 125.1 vs. 83.6 ± 51.3 pmol/mg/min, p = 0.003). Treatment of HL-1 atrial cells with angiotensin II, a known modulator of atrial structural remodeling, resulted in upregulation of NOX4 and H2O2 production, further implicating a potential role of NOX4 in atrial remodeling. Conclusion: Our data represent the first implication that NOX4-derived H2O2 may play an important role in the etiologies of AF. PMID:22679437

  6. Left atrial longitudinal strain parameters predict postoperative persistent atrial fibrillation following mitral valve surgery: a speckle tracking echocardiography study.

    PubMed

    Candan, Ozkan; Ozdemir, Nihal; Aung, Soe Moe; Dogan, Cem; Karabay, Can Yucel; Gecmen, Cetin; Omaygenç, Onur; Güler, Ahmet

    2013-10-01

    Postoperative atrial fibrillation (POAF) is common after cardiac surgery and is associated with increased morbidity, mortality, and prolonged hospital stay. Speckle tracking echocardiography (STE) has been applied recently for evaluation of LA function. The purpose of this study was to examine whether left atrial longitudinal strain measured by STE is a predictor for the development of POAF following mitral valve surgery for severe mitral regurgitation. We studied 53 patients undergoing mitral valve surgery in sinus rhythm at the time of surgery. Echocardiography with evaluation of LA strain by STE was performed. Detection of POAF was based on documentation of AF episodes by continuous telemetry throughout hospitalization. Patients who did not develop POAF were taken as group 1 and those who had POAF constituted group 2. The echocardiographic and clinical predictors of POAF were investigated. POAF occurred in 28.3% of subjects. Mean age, LAVi and BNP were found higher in group 2 while peak atrial longitudinal strain (PALS) (13.9 ± 3.8% vs. 24.8 ± 7.3%; P < 0.001), peak atrial contraction strain (PACS) (7.6 ± 1.95% vs. 11.3 ± 3.5%; P < 0.001) were significantly lower. By multivariate logistic regression analysis, PALS and LAVi were independent predictor of POAF development. LA longitudinal strain was found to predict POAF in patients undergoing mitral valve surgery. It could be used to better identify patients at greater risk of developing POAF, and thus to guide in risk stratification and to take appropriate intensive prophylactic therapy.

  7. The management of patients with atrial fibrillation undergoing percutaneous coronary intervention with stent implantation: in-hospital-data from the Atrial Fibrillation undergoing Coronary Artery Stenting study.

    PubMed

    Schlitt, Axel; Rubboli, Andrea; Lip, Gregory Y H; Lahtela, Heli; Valencia, Josè; Karjalainen, Pasi P; Weber, Michael; Laine, Mika; Kirchhof, Paulus; Niemelä, Matti; Vikman, Saila; Buerke, Michael; Airaksinen, K E Juhani

    2013-12-01

    Current recommendations on the management of patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention with stent (PCI-S) essentially derive from small, single-center, retrospective datasets. To obtain larger and better quality data, we carried out the prospective, multicenter Atrial Fibrillation undergoing Coronary Artery Stenting (AFCAS) study. Therefore, consecutive patients with history of or ongoing AF undergoing PCI-S were enrolled, and occurrence of adverse ischemic and bleeding events recorded during 12 months follow-up. In this article, we report the in-hospital observations. Out of the 963 patients, in the majority of cases (49.1%) AF was permanent. The associated risk of stroke, as defined by a CHADS2 -score ≥2, was in 70% of patients moderate to high. Upon enrollment in the registry, 69.3% of patients were on VKA therapy. Overall occurrence of in-hospital major adverse cardiac events was 4.5% (cardiovascular death 1.9%, urgent revascularization in 1.5%, and stroke/arterial thromboembolism in 0.6%). Bleeding complications occurred in 7.1% of patients, being severe in 2.5%. In a logistic regression analysis, no risk factor was independently associated with bleeding events, whereas Clopidogrel treatment decreased and female gender/treatment with gpIIb/IIIa-antagonists, respectively increased the risk for the combined ischemic endpoint. The majority of AF patients undergoing PCI-S are at high stroke risk, and therefore VKA treatment should not be withdrawn and combined anticoagulant and antiplatelet treatment is warranted. Current management appears largely in accordance with current recommendations, whereby accounting for the limited occurrence of in-hospital adverse ischemic and bleeding events.

  8. The role of gap junctions in stretch-induced atrial fibrillation

    PubMed Central

    Ueda, Norihiro; Yamamoto, Mitsuru; Honjo, Haruo; Kodama, Itsuo; Kamiya, Kaichiro

    2014-01-01

    Aims The aim of this study was to investigate the role of gap junctions in atrial fibrillation (AF) by analysing the effects of a gap junction enhancer and blocker on AF vulnerability and electrophysiological properties of isolated hearts. Methods and results The acute atrial stretch model of AF in the isolated rabbit heart was used. Sustained AF (SAF) was induced by a burst of high-frequency stimulation of the Bachmann's bundle. The effective refractory period (ERP) was measured, and the total conduction time (TCT) and the pattern of conduction of the anterior surface of the left atrium were monitored by using an optical mapping system. The effect of enhancing gap junction function by 100–1000 nM rotigaptide (ZP123) and block by 30 μM carbenoxolone on these parameters was measured. SAF inducibility was increased with an elevation of intra-atrial pressure. Enhanced gap junction conductance induced by treatment with 100–1000 nM rotigaptide reduced SAF inducibility, and the gap junction blocker carbenoxolone increased SAF inducibility. In the absence of gap junction enhancer or blocker, normal conduction was observed at 0 cmH2O. When intra-atrial pressure was raised to 12 cmH2O, the conduction pattern was changed to a heterogeneous zig-zag pattern and TCT was prolonged. Conduction pattern was not affected by either agent. Rotigaptide shortened TCT, whereas carbenoxolone prolonged TCT. ERP was significantly shortened with an increase in intra-atrial pressure, but ERP was unaffected by either agent. Conclusion Gap junction modulators changed AF inducibility through their effects on atrial conduction, not by altering ERP. PMID:25183791

  9. Inhibition of the renin-angiotensin system for prevention of atrial fibrillation.

    PubMed

    Zografos, Theodoros; Katritsis, Demosthenes G

    2010-10-01

    Atrial fibrillation (AF) is a source of considerable morbidity and mortality. There has been compelling evidence supporting the role of renin-angiotensin system (RAS) in the genesis and perpetuation of AF through atrial remodeling, and experimental studies have validated the utilization of RAS inhibition for AF prevention. This article reviews clinical trials on the use of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) for the prevention of AF. Results have been variable, depending on the clinical background of treated patients. ACEIs and ARBs appear beneficial for primary prevention of AF in patients with heart failure, whereas they are not equally effective in hypertensive patients with normal left ventricular function. Furthermore, the use of ACEIs or ARBs for secondary prevention of AF has been found beneficial only after electrical cardioversion. Additional data are needed to establish the potential clinical role of renin-angiotensin inhibition for prevention of AF.

  10. [Unexpected atrial fibrillation when monitoring in operating room. Case of the trimester].

    PubMed

    2014-05-01

    A real case reported to the SENSAR database of incidents is presented. In a patient scheduled for nose fracture repair surgery an unexpected atrial fibrillation was found when monitored in the operating room. The operation was not delayed. After induction of general anaesthesia heart rate suddenly increased and hemodinamic situation was impaired. Cardioversion was required. Two electric countershocks were given but sinus rhythm was not restored. Heart rate was controlled with amiodarone infusion. Optimal defibrillation characteristics are described in these cases. Increased risk of thromboembolism (1-2%) following cardioversion is present even if atrial thrombi are ruled out. The mainstay therapies of are rhythm and rate control and prevention of thromboembolic complications. We describe recommendations on the management of these critical situations with emphasis in learning through the creation of protocols and training practice in simulation.

  11. Inflammation fueling atrial fibrillation substrate: seeking ways to "cool" the heart.

    PubMed

    Giannopoulos, Georgios; Cleman, Michael W; Deftereos, Spyridon

    2014-01-01

    Atrial fibrillation (AF) is the most common chronic arrhythmia and a source of significant morbidity and mortality. Previous studies have identified numerous risk factors for the development of AF, including hypertension, diabetes mellitus and heart failure, which have known pathophysiologic links with inflammatory processes. The importance of inflammation in inducing and perpetuating AF has been highlighted not only by experimental, epidemiological and cohort observational studies, but also by clinical trials providing evidence that inflammatory pathways are involved in AF pathogenesis. Local and systemic measurements of biomarkers and inflammatory mediators, as well as atrial biopsy studies have also given insight as to the purported relationship between this arrhythmia and inflammation. However, the link between inflammation and AF is still poorly defined and several issues remain unresolved. The present review offers an overview of existing evidence supporting the "inflammatory" hypothesis for AF pathophysiology and potential therapeutic means for counteracting this "foul interplay" between arrhythmia and inflammation.

  12. [Unexpected atrial fibrillation when monitoring in operating room. Case of the trimester].

    PubMed

    2014-05-01

    A real case reported to the SENSAR database of incidents is presented. In a patient scheduled for nose fracture repair surgery an unexpected atrial fibrillation was found when monitored in the operating room. The operation was not delayed. After induction of general anaesthesia heart rate suddenly increased and hemodinamic situation was impaired. Cardioversion was required. Two electric countershocks were given but sinus rhythm was not restored. Heart rate was controlled with amiodarone infusion. Optimal defibrillation characteristics are described in these cases. Increased risk of thromboembolism (1-2%) following cardioversion is present even if atrial thrombi are ruled out. The mainstay therapies of are rhythm and rate control and prevention of thromboembolic complications. We describe recommendations on the management of these critical situations with emphasis in learning through the creation of protocols and training practice in simulation. PMID:24287084

  13. Sodium Channel Mutations and Susceptibility to Heart Failure and Atrial Fibrillation

    PubMed Central

    Olson, Timothy M.; Michels, Virginia V.; Ballew, Jeffrey D.; Reyna, Sandra P.; Karst, Margaret L.; Herron, Kathleen J.; Horton, Steven C.; Rodeheffer, Richard J.; Anderson, Jeffrey L.

    2007-01-01

    Context Dilated cardiomyopathy (DCM), a genetically heterogeneous disorder, causes heart failure and rhythm disturbances. The majority of identified DCM genes encode structural proteins of the contractile apparatus and cytoskeleton. Recently, genetic defects in calcium and potassium regulation have been discovered in patients with DCM, implicating an alternative disease mechanism. The full spectrum of genetic defects in DCM, however, has not been established. Objectives To identify a novel gene for DCM at a previously mapped locus, define the spectrum of mutations in this gene within a DCM cohort, and determine the frequency of DCM among relatives inheriting a mutation in this gene. Design, Setting, and Participants Refined mapping of a DCM locus on chromosome 3p in a multigenerational family and mutation scanning in 156 unrelated pro-bands with DCM, prospectively identified at the Mayo Clinic between 1987 and 2004. Relatives underwent screening echocardiography and electrocardiography and DNA sample procurement. Main Outcome Measure Correlation of identified mutations with cardiac phenotype. Results Refined locus mapping revealed SCN5A, encoding the cardiac sodium channel, as a candidate gene. Mutation scans identified a missense mutation (D1275N) that cosegregated with an age-dependent, variably expressed phenotype of DCM, atrial fibrillation, impaired automaticity, and conduction delay. In the DCM cohort, additional missense (T220I, R814W, D1595H) and truncation (2550-2551insTG) SCN5A mutations, segregating with cardiac disease or arising de novo, were discovered in unrelated probands. Among individuals with an SCN5A mutation 27% had early features of DCM (mean age at diagnosis, 20.3 years), 38% had DCM (mean age at diagnosis, 47.9 years), and 43% had atrial fibrillation (mean age at diagnosis, 27.8 years). Conclusions Heritable SCN5A defects are associated with susceptibility to early-onset DCM and atrial fibrillation. Similar or even identical mutations may

  14. Atrial Fibrillation in Decompensated Heart Failure: Associated Factors and In-Hospital Outcome

    PubMed Central

    Mendes, Fernanda de Souza Nogueira Sardinha; Atié, Jacob; Garcia, Marcelo Iorio; Gripp, Eliza de Almeida; de Sousa, Andréa Silvestre; Feijó, Luiz Augusto; Xavier, Sergio Salles

    2014-01-01

    Background Studies on atrial fibrillation (AF) in decompensated heart failure (DHF) are scarce in Brazil. Objectives To determine AF prevalence, its types and associated factors in patients hospitalized due to DHF; to assess their thromboembolic risk profile and anticoagulation rate; and to assess the impact of AF on in-hospital mortality and hospital length of stay. Methods Retrospective, observational, cross-sectional study of incident cases including 659 consecutive hospitalizations due to DHF, from 01/01/2006 to 12/31/2011. The thromboembolic risk was assessed by using CHADSVASc score. On univariate analysis, the chi-square, Student t and Mann Whitney tests were used. On multivariate analysis, logistic regression was used. Results The prevalence of AF was 40%, and the permanent type predominated (73.5%). On multivariate model, AF associated with advanced age (p < 0.0001), non-ischemic etiology (p = 0.02), right ventricular dysfunction (p = 0.03), lower systolic blood pressure (SBP) (p = 0.02), higher ejection fraction (EF) (p < 0.0001) and enlarged left atrium (LA) (p < 0.0001). The median CHADSVASc score was 4, and 90% of the cases had it ≥ 2. The anticoagulation rate was 52.8% on admission and 66.8% on discharge, being lower for higher scores. The group with AF had higher in-hospital mortality (11.0% versus 8.1%, p = 0.21) and longer hospital length of stay (20.5 ± 16 versus 16.3 ± 12, p = 0.001). Conclusions Atrial fibrillation is frequent in DHF, the most prevalent type being permanent AF. Atrial fibrillation is associated with more advanced age, non-ischemic etiology, right ventricular dysfunction, lower SBP, higher EF and enlarged LA. Despite the high thromboembolic risk profile, anticoagulation is underutilized. The presence of AF is associated with longer hospital length of stay and high mortality. PMID:25352505

  15. Pharmacological exploration of the resting membrane potential reserve: Impact on atrial fibrillation.

    PubMed

    van der Heyden, Marcel A G; Jespersen, Thomas

    2016-01-15

    The cardiac action potential arises and spreads throughout the myocardium as a consequence of highly organized spatial and temporal expression of ion channels conducting Na(+), Ca(2+) or K(+) currents. The cardiac Na(+) current is responsible for the initiation and progression of the action potential. Altered Na(+) current has been found implicated in a number of different arrhythmias, including atrial fibrillation. In the atrium, the resting membrane potential is more depolarized than in the ventricles, and as cardiac Na(+) channels undergo voltage-dependent inactivation close to this potential, minor changes in the membrane potential have a relatively large impact on the atrial Na(+) current. The atrial resting membrane potential is established following ionic currents through the inwardly rectifying K(+) currents IK1, IK,ACh and IK,Ca and to a lesser extent by other ion channels as well as by exchangers and pumps. This review will focus on the relative and regulated contribution of IK1, IK,ACh and IK,Ca, and on pharmacological modification of the channels underlying these currents in respect to the resting membrane potential, Na(+) channel availability and atrial electrophysiology in health and disease. PMID:26601803

  16. Evaluation of catheter ablation of periatrial ganglionic plexi in patients with atrial fibrillation.

    PubMed

    Danik, Stephan; Neuzil, Petr; d'Avila, Andre; Malchano, Zachary J; Kralovec, Stepan; Ruskin, Jeremy N; Reddy, Vivek Y

    2008-09-01

    Recent data suggests that the cardiac autonomic nervous system has an important role in the initiation and maintenance of atrial fibrillation (AF). This study investigated (1) the feasibility of identifying and targeting these autonomic ganglia using endocardial radiofrequency stimulation and ablation, respectively; (2) the efficacy of endocardial ablation to completely eliminate the vagal response elicited from epicardial stimulation; and (3) the effect of autonomic ablation on the acute inducibility of AF. The study included 18 patients referred for catheter ablation of suspected vagal-mediated AF. The endocardial left atrial surface was stimulated at high frequency (20 to 50 Hz) to elicit a vagal response. In selected patients (n = 5), pericardial access was obtained using a subxyphoid puncture to permit epicardial stimulation. Catheter ablation of the putative autonomic ganglionic sites was performed from the left atrial endocardium using irrigated radiofrequency energy. After ablation of all identifiable autonomic ganglia, high-frequency pacing was repeated to induce AF. In all patients, stimulation at certain endocardial sites elicited a vagal response. Endocardial ablation abrogated this vagal responsiveness. Furthermore, for sites accessible from the pericardium, the vagal response elicited using epicardial stimulation was also eliminated. Despite successful ablation of these ganglia, AF was still inducible in 17 of 18 patients. In conclusion, successful ablation of autonomic ganglia from an endocardial approach can be reliably achieved using an irrigated catheter. In addition, ablation of these structures in patients with vagal-mediated AF is insufficient to prevent its acute reinduction with high-frequency atrial stimulation. PMID:18721515

  17. Effects of Persistent Atrial Fibrillation-Induced Electrical Remodeling on Atrial Electro-Mechanics – Insights from a 3D Model of the Human Atria

    PubMed Central

    Adeniran, Ismail; MacIver, David H.; Garratt, Clifford J.; Ye, Jianqiao; Hancox, Jules C.; Zhang, Henggui

    2015-01-01

    Aims Atrial stunning, a loss of atrial mechanical contraction, can occur following a successful cardioversion. It is hypothesized that persistent atrial fibrillation-induced electrical remodeling (AFER) on atrial electrophysiology may be responsible for such impaired atrial mechanics. This simulation study aimed to investigate the effects of AFER on atrial electro-mechanics. Methods and Results A 3D electromechanical model of the human atria was developed to investigate the effects of AFER on atrial electro-mechanics. Simulations were carried out in 3 conditions for 4 states: (i) the control condition, representing the normal tissue (state 1) and the tissue 2–3 months after cardioversion (state 2) when the atrial tissue recovers its electrophysiological properties after completion of reverse electrophysiological remodelling; (ii) AFER-SR condition for AF-remodeled tissue with normal sinus rhythm (SR) (state 3); and (iii) AFER-AF condition for AF-remodeled tissue with re-entrant excitation waves (state 4). Our results indicate that at the cellular level, AFER (states 3 & 4) abbreviated action potentials and reduced the Ca2+ content in the sarcoplasmic reticulum, resulting in a reduced amplitude of the intracellular Ca2+ transient leading to decreased cell active force and cell shortening as compared to the control condition (states 1 & 2). Consequently at the whole organ level, atrial contraction in AFER-SR condition (state 3) was dramatically reduced. In the AFER-AF condition (state 4) atrial contraction was almost abolished. Conclusions This study provides novel insights into understanding atrial electro-mechanics illustrating that AFER impairs atrial contraction due to reduced intracellular Ca2+ transients. PMID:26606047

  18. The ORBIT bleeding score: a simple bedside score to assess bleeding risk in atrial fibrillation

    PubMed Central

    O'Brien, Emily C.; Simon, DaJuanicia N.; Thomas, Laine E.; Hylek, Elaine M.; Gersh, Bernard J.; Ansell, Jack E.; Kowey, Peter R.; Mahaffey, Kenneth W.; Chang, Paul; Fonarow, Gregg C.; Pencina, Michael J.; Piccini, Jonathan P.; Peterson, Eric D.

    2015-01-01

    Background Therapeutic decisions in atrial fibrillation (AF) are often influenced by assessment of bleeding risk. However, existing bleeding risk scores have limitations. Objectives We sought to develop and validate a novel bleeding risk score using routinely available clinical information to predict major bleeding in a large, community-based AF population. Methods We analysed data from Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF), a prospective registry that enrolled incident and prevalent AF patients at 176 US sites. Using Cox proportional hazards regression, we identified factors independently associated with major bleeding among patients taking oral anticoagulation (OAC) over a median follow-up of 2 years (interquartile range = 1.6–2.5). We also created a numerical bedside risk score that included the five most predictive risk factors weighted according to their strength of association with major bleeding. The predictive performance of the full model, the simple five-item score, and two existing risk scores (hypertension, abnormal renal/liver function, stroke, bleeding history or predisposition, labile INR, elderly, drugs/alcohol concomitantly, HAS-BLED, and anticoagulation and risk factors in atrial fibrillation, ATRIA) were then assessed in both the ORBIT-AF cohort and a separate clinical trial population, Rivaroxaban Once-daily oral direct factor Xa inhibition compared with vitamin K antagonism for prevention of stroke and embolism trial in atrial fibrillation (ROCKET-AF). Results Among 7411 ORBIT-AF patients taking OAC, the rate of major bleeding was 4.0/100 person-years. The full continuous model (12 variables) and five-factor ORBIT risk score (older age [75+ years], reduced haemoglobin/haematocrit/history of anaemia, bleeding history, insufficient kidney function, and treatment with antiplatelet) both had good ability to identify those who bled vs. not (C-index 0.69 and 0.67, respectively). These scores both had

  19. Comparison of Risk of Atrial Fibrillation in Black Versus White Patients After Coronary Artery Bypass Grafting.

    PubMed

    Efird, Jimmy T; Gudimella, Preeti; O'Neal, Wesley T; Griffin, William F; Landrine, Hope; Kindell, Linda C; Davies, Stephen W; Sarpong, Daniel F; O'Neal, Jason B; Crane, Patricia; Nelson, Margaret A; Ferguson, Thomas Bruce; Chitwood, Walter Randolph; Kypson, Alan P; Anderson, Ethan J

    2016-04-01

    Obesity has been identified as a risk factor for postoperative atrial fibrillation (POAF) after coronary artery bypass grafting (CABG). However, no studies have addressed the influence of race on this association. A total of 13,594 patients undergoing first-time, isolated CABG without preoperative AF between 1992 and 2011 were included in our study. The association between body mass index and POAF was compared by race. Relative risk and 95% CIs were computed using maximum likelihood log-binomial regression. Increasing levels of body mass index were associated with higher POAF risk after CABG in black but not white patients (pinteraction = 0.0009).

  20. Prediction and personalised treatment of atrial fibrillation-stroke prevention: consolidated position paper of CVD professionals.

    PubMed

    Helms, Thomas M; Duong, Giang; Zippel-Schultz, Bettina; Tilz, Roland Richard; Kuck, Karl-Heinz; Karle, Christoph A

    2014-01-01

    Atrial fibrillation (AF) is one of the major morbidity and health economic factors in Europe and often associated with several co-morbidities. This paper (1) underlines the importance of highly professional AF management utilising a multi-disciplinary expertise, especially considering the role of AF regarding the stroke risk and prevention, (2) demonstrates the consolidated position of CVD professionals and (3) emphasises those research aspects that could deepen the understanding of the emergence and the treatment of AF and therefore helps to provide a personalised preventive and more effective management of AF. Specialised calls are considered for that within the new European Programme 'Horizon 2020'.

  1. Outcomes of Temporary Interruption of Rivaroxaban Compared With Warfarin in Patients With Nonvalvular Atrial Fibrillation

    PubMed Central

    Sherwood, Matthew W.; Douketis, James D.; Patel, Manesh R.; Piccini, Jonathan P.; Hellkamp, Anne S.; Lokhnygina, Yuliya; Spyropoulos, Alex C.; Hankey, Graeme J.; Singer, Daniel E.; Nessel, Christopher C.; Mahaffey, Kenneth W.; Fox, Keith A. A.; Califf, Robert M.; Becker, Richard C.

    2014-01-01

    Background During long-term anticoagulation in atrial fibrillation, temporary interruptions (TIs) of therapy are common, but the relationship between patient outcomes and TIs has not been well studied. We sought to determine reasons for TI, the characteristics of patients undergoing TI, and the relationship between anticoagulant and outcomes among patients with TI. Methods and Results In the Rivaroxaban Once Daily, Oral, Direct Factor Xa Inhibition Compared With Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF), a randomized, double-blind, double-dummy study of rivaroxaban and warfarin in nonvalvular atrial fibrillation, baseline characteristics, management, and outcomes, including stroke, non–central nervous system systemic embolism, death, myocardial infarction, and bleeding, were reported in participants who experienced TI (3–30 days) for any reason. The at-risk period for outcomes associated with TI was from TI start to 30 days after resumption of study drug. In 14 236 participants who received at least 1 dose of study drug, 4692 (33%) experienced TI. Participants with TI were similar to the overall ROCKET AF population in regard to baseline clinical characteristics. Only 6% (n=483) of TI incidences involved bridging therapy. Stroke/systemic embolism rates during the at-risk period were similar in rivaroxaban-treated and warfarin-treated participants (0.30% versus 0.41% per 30 days; hazard ratio [confidence interval]=0.74 [0.36–1.50]; P=0.40). Risk of major bleeding during the at-risk period was also similar in rivaroxaban-treated and warfarin-treated participants (0.99% versus 0.79% per 30 days; hazard ratio [confidence interval]=1.26 [0.80–2.00]; P=0.32). Conclusions TI of oral anticoagulation is common and is associated with substantial stroke risks and bleeding risks that were similar among patients treated with rivaroxaban or warfarin. Further investigation is needed to determine the optimal

  2. Obesity, Exercise, Obstructive Sleep Apnea, and Modifiable Atherosclerotic Cardiovascular Disease Risk Factors in Atrial Fibrillation.

    PubMed

    Miller, Jared D; Aronis, Konstantinos N; Chrispin, Jonathan; Patil, Kaustubha D; Marine, Joseph E; Martin, Seth S; Blaha, Michael J; Blumenthal, Roger S; Calkins, Hugh

    2015-12-29

    Classically, the 3 pillars of atrial fibrillation (AF) management have included anticoagulation for prevention of thromboembolism, rhythm control, and rate control. In both prevention and management of AF, a growing body of evidence supports an increased role for comprehensive cardiac risk factor modification (RFM), herein defined as management of traditional modifiable cardiac risk factors, weight loss, and exercise. In this narrative review, we summarize the evidence demonstrating the importance of each facet of RFM in AF prevention and therapy. Additionally, we review emerging data on the importance of weight loss and cardiovascular exercise in prevention and management of AF. PMID:26718677

  3. The Presence of a Large Chiari Network in a Patient with Atrial Fibrillation and Stroke

    PubMed Central

    Schwimmer-Okike, Nneka; Niebuhr, Johannes; Schramek, Grit Gesine Ruth; Frantz, Stefan

    2016-01-01

    The Chiari network is an embryological remnant found in the right atrium, mostly without any significant pathophysiological consequences. However, several cardiac associations are reported in the literature including supraventricular tachyarrhythmias. We present a case of a 96-year-old body donor with a stroke episode and intermittent atrial fibrillations. The dissection of the heart revealed the presence of an immense Chiari network with a large central thrombus. The role of a Chiari network in the pathogenesis of stroke and pulmonary embolism is discussed. PMID:27547469

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

    PubMed

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

    2009-08-01

    We conducted meta-analyses of genome-wide association studies for atrial fibrillation (AF) in participants from five community-based cohorts. Meta-analyses of 896 prevalent (15,768 referents) and 2,517 incident (21,337 referents) AF cases identified a new locus for AF (ZFHX3, rs2106261, risk ratio RR = 1.19; P = 2.3 x 10(-7)). We replicated this association in an independent cohort from the German AF Network (odds ratio = 1.44; P = 1.6 x 10(-11); combined RR = 1.25; combined P = 1.8 x 10(-15)).

  5. The first case of atrial fibrillation-related graft kidney infarction following acute pyelonephritis.

    PubMed

    Tsai, Shang-Feng

    2014-01-01

    Native renal infarction is uncommon in patients with atrial fibrillation (AF)-related thromboembolism. Graft infarction is also rare, with such cases mostly occurring in the main graft artery postoperatively. To date, there have been no studies of AF-related graft kidney infarction. We herein describe the first case of AF-related graft kidney infarction. The clinical manifestations of this condition mimic and follow those of acute pyelonephritis; therefore, these diseases should be differentially diagnosed as early as possible using lactic dehydrogenase testing and computed tomography. Aggressive treatment with intravascular thrombolysis should be administered, even when the diagnosis is delayed, in order to restore a viable renal function.

  6. Cerebrovascular Complications Related to Atrial Fibrillation Ablation and Strategies for Periprocedural Stroke Prevention.

    PubMed

    Csanadi, Zoltan; Nagy-Baló, Edina; Danik, Stephan; Barrett, Conor; Burkhardt, J David; Sanchez, Javier; Santangeli, Pasquale; Santoro, Francesco; Di Biase, Luigi; Natale, Andrea

    2014-03-01

    Transcatheter treatment of atrial fibrillation (AF) is a complex intervention performed in patients who are at inherently increased risk of a thromboembolic complication, including stroke. It is therefore not surprising that cerebrovascular accidents have been among the most feared complications since the inception of AF ablation. While improvements have been made to limit the incidence of thromboembolic events during catheter ablation of AF, the optimal strategy to minimize such complications has yet to be determined. It is hoped that larger trials using periprocedural anticoagulation strategies can be undertaken to definitively address these important concerns. PMID:27063826

  7. New Oral Anticoagulants for Stroke Prevention in Atrial Fibrillation: More Choices Bring More Challenges

    PubMed Central

    Howard, Patricia A.

    2013-01-01

    For patients with atrial fibrillation, anticoagulant therapy is essential to reduce the risk of ischemic stroke that is associated with this arrhythmia. Historically, warfarin has been the preferred treatment for patients at moderate to high risk despite many potential limitations. With the development of newer oral anticoagulants, clinicians now have 3 additional options: dabigatran, rivaroxaban, and apixaban. Although these agents clearly offer some advantages over warfarin, they may not be appropriate for all patients. This article will discuss factors that should be considered when selecting among these various anticoagulants. PMID:24421491

  8. Use of novel oral anticoagulant agents in atrial fibrillation: current evidence and future perspective

    PubMed Central

    Madan, Shivanshu; Shah, Shenil; Partovi, Sasan

    2014-01-01

    The increasing availability of novel oral anticoagulants (NOAC) for the prevention of stroke and systemic embolism in patients with nonvalvular atrial fibrillation (AF) offers alternatives for patients currently prescribed warfarin. This article provides a brief overview on the mechanism and clinical use of these drugs as well as a review of the pivotal clinical trials providing the basis for each agent’s safety and efficacy. While these agents are currently Food and Drug Administration (FDA) approved for anticoagulation of patients with nonvalvular AF, additional studies continually emerge offering further insight into the application of these agents in other areas. PMID:25276617

  9. Atrial fibrillation in patients with diabetes: molecular mechanisms and therapeutic perspectives

    PubMed Central

    De Potter, Tom; Cresti, Alberto; Severi, Silva; Breithardt, Günter

    2015-01-01

    Atrial fibrillation (AF) remains the most frequent sustained cardiac arrhythmia worldwide and its incidence increases with ageing, cardiovascular risk factors and comorbidities. Prevalence of diabetes mellitus (DM) is growing fast and is assuming pandemic proportions mostly due to overnutrition and sedentary habits. Experimental and clinical evidences suggest that DM and AF are strongly interconnected. The present review addresses in detail new molecular pathways implicated in the etiology of AF and their relevance for mechanism-based therapeutic strategies in this setting. Advances in risk stratification, drug therapy (i.e., novel anticoagulants) and catheter ablation are also described. PMID:26543823

  10. Left atrial enlargement is an independent predictor of stroke and systemic embolism in patients with non-valvular atrial fibrillation

    PubMed Central

    Hamatani, Yasuhiro; Ogawa, Hisashi; Takabayashi, Kensuke; Yamashita, Yugo; Takagi, Daisuke; Esato, Masahiro; Chun, Yeong-Hwa; Tsuji, Hikari; Wada, Hiromichi; Hasegawa, Koji; Abe, Mitsuru; Lip, Gregory Y. H.; Akao, Masaharu

    2016-01-01

    Controversy exists regarding whether left atrial enlargement (LAE) is a predictor of stroke/systemic embolism (SE) in atrial fibrillation (AF) patients. The Fushimi AF Registry, a community-based prospective survey, enrolled all AF patients in Fushmi-ku, Japan, from March 2011. Follow-up data and baseline echocardiographic data were available for 2,713 patients by August 2015. We compared backgrounds and incidence of events over a median follow-up of 976.5 days between patients with LAE (left atrial diameter > 45 mm; LAE group) and those without in the Fushimi AF Registry. The LAE group accounted for 39% (n = 1,049) of cohort. The LAE group was older and had longer AF duration, with more prevalent non-paroxysmal AF, higher CHADS2/CHA2DS2-VASc score, and oral anticoagulant (OAC) use. A higher risk of stroke/SE during follow-up in the LAE group was found (entire cohort; hazard ratio (HR): 1.92, 95% confidence interval (CI): 1.40–2.64; p < 0.01; without OAC; HR: 1.97, 95% CI: 1.18–3.25; p < 0.01; with OAC; HR: 1.83, 95% CI: 1.21–2.82; p < 0.01). LAE was independently associated with increased risk of stroke/SE (HR: 1.74, 95% CI: 1.25–2.42; p < 0.01) after adjustment by the components of CHA2DS2-VASc score and OAC use. In conclusion, LAE was an independent predictor of stroke/SE in large community cohort of AF patients. PMID:27485817

  11. Combined catheter ablation for atrial fibrillation and Watchman® left atrial appendage occlusion procedures: Five-year experience

    PubMed Central

    Phillips, Karen P.; Walker, Daniel T.; Humphries, Julie A.

    2015-01-01

    Background Patients with atrial fibrillation (AF) may benefit from undergoing concomitant interventions of left atrial catheter ablation and device occlusion of the left atrial appendage (LAA) as a two-pronged strategy for rhythm control and stroke prevention. We report on the outcome of combined procedures in a single center case series over a 5-year timeframe. Methods Ninety-eight patients with non-valvular AF and a mean CHA2DS2-VASc score 2.6±1.0 underwent either first time, or redo pulmonary vein isolation (PVI) procedures, followed by successful implant of a Watchman® device. Results All procedures were generally uncomplicated with a mean case time of 213±40 min. Complete LAA occlusion was achieved at initial implant in 92 (94%) patients. Satisfactory LAA occlusion was achieved in 100% of patients at 12 months, with a complete LAA occlusion rate of 86%. All patients discontinued oral anticoagulation. Persistent late peri-device leaks were more frequently associated with device angulation or shoulder protrusion, and were associated with a significantly lower achieved device compression of 12±3% vs. 15±5% (p<0.01) than complete occlusion. One ischemic stroke was recorded over a mean follow-up time of 802±439 days. Twelve months׳ freedom from detectable AF was achieved in 77% of patients. Conclusions Combined procedures of catheter ablation for AF and Watchman® LAA implant appear to be feasible and safe, with excellent rates of LAA occlusion achieved and an observed stroke rate of 0.5% per year during mid-term follow-up. Incomplete occlusion was associated with lower achieved device compression and was more frequently associated with suboptimal device position. PMID:27092193

  12. Relations between circulating microRNAs and atrial fibrillation: data from the Framingham Offspring Study

    PubMed Central

    McManus, David D.; Lin, Honghuang; Tanriverdi, Kahraman; Quercio, Michael; Yin, Xiaoyan; Larson, Martin G.; Ellinor, Patrick T.; Levy, Daniel; Freedman, Jane E.; Benjamin, Emelia J.

    2014-01-01

    Background MicroRNA (miRNA) expression in atrial tissue has been implicated in pathologic susceptibility to atrial fibrillation (AF). Nevertheless, data are limited on how circulating levels relate to AF. Objective To test the hypothesis that circulating miRNAs would be associated with AF. Methods Among 2445 Framingham Heart Study Offspring participants, we measured the expression of 385 circulating whole blood miRNAs by high-throughput quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR). We related miRNA levels with prevalent and new-onset AF. Results The mean age in the cohort was 66.3 ± 8.9 years and 56% were women; 153 participants had clinically apparent AF at baseline and 107 developed AF during a median of 5.4 years of follow-up. miRNA-328 (miR-328) expression was lower among participants with prevalent AF [8.76 cycle threshold (Ct)] compared to individuals with no AF (7.75 Ct, p <0.001). The association between miR-328 and prevalent AF persisted after adjustment for age, sex, and technical covariates (OR=1.21, P = 1.8 × 10−4) but was attenuated in analyses adjusting for clinical AF risk factors (OR=1.14, P = 0.017). In contrast to the associations between miR-328 and prevalent AF, none of the circulating miRNAs were associated with incident AF. Conclusions Circulating levels of miR-328, a miRNA known to promote atrial electrical remodeling by reducing L-type Ca2+ channel density, were associated with prevalent AF. Adjustment for risk factors that promote atrial remodeling, including hypertension, attenuated the association between miR-328 and AF, potentially implicating miR-328 as a potential mediator of atrial remodeling and AF vulnerability. PMID:24444445

  13. Effects of Anatomical Structure on Initiation and Maintenance of Atrial Fibrillation in a Computer Model of Human Atria

    NASA Astrophysics Data System (ADS)

    Cherry, Elizabeth M.; Fenton, Flavio H.; Hastings, Harold M.; Evans, Steven J.

    2002-03-01

    We analyze the behavior of atrial fibrillation in a simulated model of human atria in order to better understand the role of the intricate atrial structure in arrhythmia initiation and maintenance. A cellular ionic model based on human atrial action potentials is used, with parameter values that reproduce the electrophysiology of both healthy and diseased atrial cells. We illustrate how the interatrial (right-left) connections and other anatomical structures function during sinus rhythm and during arrhythmias. In particular, we show the effects of wavelength and atrial size on the dynamics and stability of reentrant waves using healthy and diseased electrophysiological parameters. Our findings indicate that structural remodeling characteristic of diseased atria is an important destabilizing factor for reentrant waves in this complex geometry, as observed clinically.

  14. Independence and symbolic independence of nonstationary heartbeat series during atrial fibrillation

    NASA Astrophysics Data System (ADS)

    Cammarota, Camillo; Rogora, Enrico

    2005-08-01

    Heartbeat intervals during atrial fibrillation are commonly believed to form a series of almost independent variables. The series extracted from 24 h Holter recordings show a nonstationary behavior. Because of nonstationarity it is difficult to give a quantitative measure of independence. In this paper, we use and compare two methods for this. The first is a classical method which models a nonstationary series using a linear Gaussian state space model. In this framework, the independence is tested on the stationary sequence of the residuals. The second method codes data into permutations and tests the uniformity of their distribution. This test assumes as null hypothesis a weaker form of independence which we call symbolic independence. We discuss some advantages of symbolic independence in the context of heartbeat series. We analyze the time series of heartbeat intervals from 24 h Holter recordings of nine subjects with chronic atrial fibrillation and find that the detrended series is a zero or one memory process for 83% of regular segments and is symbolically independent for 93% of segments.

  15. The Registry of the German Competence NETwork on Atrial Fibrillation: patient characteristics and initial management

    PubMed Central

    Nabauer, Michael; Gerth, Andrea; Limbourg, Tobias; Schneider, Steffen; Oeff, Michael; Kirchhof, Paulus; Goette, Andreas; Lewalter, Thorsten; Ravens, Ursula; Meinertz, Thomas; Breithardt, Günter; Steinbeck, Gerhard

    2009-01-01

    Aims The aim of this study was to describe the characteristics of patients with atrial fibrillation (AF) enrolled in the Central Registry of the German Competence NETwork on Atrial Fibrillation (AFNET) and to assess current medical practice in patients treated at various levels of medical care in Germany. Methods and results From February 2004 to March 2006, 9582 ambulatory and hospitalized patients with ECG-documented AF were enrolled by 194 participating study centres from all levels of medical care in Germany. Clinical type of AF was reported as paroxysmal in 2893, persistent in 1873, and permanent in 3134 patients or classified as a first episode in 1035 patients. Predisposing conditions were common and present in 87.6% of the patients. Most patients were symptomatic with AF (75.1%). Rhythm control in persistent AF was provided to 53.4% of the symptomatic patients and to 47.8% of the patients without symptoms. Anticoagulation for stroke prevention was given to 71.4% of the patients considered eligible by applicable guidelines and to 48.4% of patients with low risk where guidelines do not recommend anticoagulation. Conclusion This registry provides insight into current medical care of patients with AF in Germany. The use of oral anticoagulation in eligible patients was among the highest reported, whereas decisions on rate and rhythm control often do not follow current recommendations. PMID:19153087

  16. Dronedarone: current evidence for its safety and efficacy in the management of atrial fibrillation

    PubMed Central

    Schweizer, Patrick A; Becker, Rüdiger; Katus, Hugo A; Thomas, Dierk

    2011-01-01

    Atrial fibrillation (AF) is the most common sustained arrhythmia. Management of AF includes rate control, rhythm control if necessary, prevention of thromboembolic events, and treatment of the underlying disease. Rate control is usually achieved by pharmacological suppression of calcium currents or by applying β-blockers or digitalis compounds. In contrast, the number of compounds available for rhythm control is still limited. Class Ic agents increase mortality in patients with structural heart disease, and amiodarone harbors an extensive side effect profile despite its efficacy in maintaining sinus rhythm. Furthermore, rhythm control by these compounds has not been shown to reduce patient mortality. Dronedarone is a new anti-arrhythmic drug that has been developed to provide rhythm and rate control in AF patients with fewer side effects compared with amiodarone. This review primarily focuses on clinical trials evaluating efficacy and safety of the novel drug. Conclusions from these studies are critically reviewed, and recommendations for clinical practice are discussed. Dronedarone significantly reduced the incidence of hospitalization due to cardiovascular events or death in high-risk patients with atrial fibrillation (ATHENA trial). However, dronedarone was less efficient than amiodarone in maintaining normal sinus rhythm (DIONYSOS trial) and is contraindicated in severe or deteriorating heart failure (ANDROMEDA trial). In summary, dronedarone represents a valuable addition to the limited spectrum of antiarrhythmic drugs and is currently recommended in patients with paroxysmal and persistent AF to achieve rate and rhythm control, excluding cases of severe or unstable congestive heart failure. PMID:21267357

  17. [Clinical characteristics of patients with persistent atrial fibrillation referred for cardioversion: Spanish Cardioversion Registry (REVERSE)].

    PubMed

    Alegret, Josep M; Viñolas, Xavier; Sagristá, Jaume; Hernández-Madrid, Antonio; Berruezo, Antonio; Moya, Angel; Martínez Sande, José L; Pastor, Agustín

    2008-06-01

    The objectives were to investigate the treatment and clinical characteristics of patients referred for cardioversion in Spain and to compare them with those reported in the AFFIRM (Atrial Fibrillation Follow-up Investigation of Rhythm Management) and RACE (RAte Control versus Electrical cardioversion) studies. The prospective study involved 1515 consecutive patients with persistent atrial fibrillation who were referred for cardioversion at 96 Spanish hospitals. Half of the patients were being treated with Vaughan-Williams group-I or -III antiarrhythmic drugs. The most frequently used approach to anticoagulation was to administer dicoumarins 34 weeks before and after cardioversion. Our patients were younger than those in the AFFIRM and RACE studies. Compared with AFFIRM patients, our patients had a lower prevalence of previous embolism, ischemic heart disease, hypertension, diabetes, and systolic dysfunction. Compared with RACE patients, our patients had a lower prevalence of ischemic heart disease and previous embolism, but a slightly higher prevalence of hypertension and diabetes. We conclude that patients referred for cardioversion in Spain clearly had a lower cardiovascular risk profile than those in the AFFIRM study, and appeared to have a lower risk profile than those in the RACE study.

  18. [Clinical characteristics of patients with persistent atrial fibrillation referred for cardioversion: Spanish Cardioversion Registry (REVERSE)].

    PubMed

    Alegret, Josep M; Viñolas, Xavier; Sagristá, Jaume; Hernández-Madrid, Antonio; Berruezo, Antonio; Moya, Angel; Martínez Sande, José L; Pastor, Agustín

    2008-06-01

    The objectives were to investigate the treatment and clinical characteristics of patients referred for cardioversion in Spain and to compare them with those reported in the AFFIRM (Atrial Fibrillation Follow-up Investigation of Rhythm Management) and RACE (RAte Control versus Electrical cardioversion) studies. The prospective study involved 1515 consecutive patients with persistent atrial fibrillation who were referred for cardioversion at 96 Spanish hospitals. Half of the patients were being treated with Vaughan-Williams group-I or -III antiarrhythmic drugs. The most frequently used approach to anticoagulation was to administer dicoumarins 34 weeks before and after cardioversion. Our patients were younger than those in the AFFIRM and RACE studies. Compared with AFFIRM patients, our patients had a lower prevalence of previous embolism, ischemic heart disease, hypertension, diabetes, and systolic dysfunction. Compared with RACE patients, our patients had a lower prevalence of ischemic heart disease and previous embolism, but a slightly higher prevalence of hypertension and diabetes. We conclude that patients referred for cardioversion in Spain clearly had a lower cardiovascular risk profile than those in the AFFIRM study, and appeared to have a lower risk profile than those in the RACE study. PMID:18570785

  19. Management of atrial fibrillation in the Emergency Department: current approach and future expectations.

    PubMed

    Russo, V; Navarin, S; Zampini, G; Magrini, L; Mann, C; Muiesan, M L; De Caterina, R; Yılmaz, M B; Beton, O; Monzani, V; Kubica, J; Müller, C; Di Somma, S

    2013-12-01

    Atrial fibrillation (AF) is the most common cardiac dysrhythmia and occurs in 3.3%-10% of emergency admissions. It is frequently quoted for people over the age of 75, but the cases of AF in young subjects without structural heart disease are also increasing, therefore, leading to the evaluation of "lonely atrial fibrillation" as a new challenge for the clinician. The first diagnosis and treatment often occur in the emergency room and the emergency physician has therefore to evaluate the initial step towards the therapeutic decisions. Although international standard guidelines are available, AF treatment in the Emergency Department (ED) is still heterogeneous in terms of the management strategy chosen. There are two main strategies for the management of AF: rate and rhythm control. Moreover, antithrombotic treatment is pivotal in AF to prevent cardioembolic stroke and it is considered a primary objective after an accurate assessment of antithrombotic treatment risks and benefits. The introduction of innovative echocardiographic approach, directly in ED, seems to improve the management and risk stratification of patients with AF. This review aims to provide an overview about the current approach and the future expectations in the management of AF in ED. This manuscript represents a synopsis of the lectures on AF management in the ED of the Third Italian GREAT Network Congress, that was hold in Rome, 15-19 October 2012. We decided to use only the most relevant references for each contribution as suggested by each participant at this review.

  20. Atrial Fibrillation Due to Over The Counter Stimulant Drugs in A Young Adult.

    PubMed

    Thyagarajan, Braghadheeswar; Alagusundaramoorthy, Sayee Sundar; Agrawal, Abhinav

    2015-08-01

    The usage of over the counter stimulant drugs and energy drinks is increasing on a day to day basis for various purposes including work, sports and leisure among individuals in all age groups. Multiple formulations are available in the market including pills, liquid capsules and drinks in various flavours. Many of them contain excessively high doses of caffeine along with a variety of stimulant compounds that have multiple effects in different parts of the human body. The consumption of such high amounts of caffeine itself has shown to have caused cardiac arrhythmias in healthy individuals and when it is mixed with a number of stimulant compounds can be associated with a number of adverse effects in the human body. However, the awareness of such life threatening complications associated with these energy drinks does not exist among people who consume it on a day to day basis. We report a case of 25-year-old Caucasian male with no significant past medical history for cardiac diseases, no risk factors for atrial fibrillation, non smoker, occasional alcohol drinker who presents with new onset atrial fibrillation with rapid ventricular response due to the consumption of over the counter stimulant energy capsule which had high doses of caffeine. PMID:26435989

  1. Optimal Duration of Monitoring for Atrial Fibrillation in Cryptogenic Stroke: A Nonsystematic Review

    PubMed Central

    Hariri, Essa; Hachem, Ahmad; Sarkis, Georges; Nasr, Samer

    2016-01-01

    Atrial fibrillation (AF) is the most common form of cardiac arrhythmias and an independent risk factor for stroke. Despite major advances in monitoring strategies, clinicians tend to miss the diagnoses of AF and especially paroxysmal AF due mainly to its asymptomatic presentation and the rather limited duration dedicated for monitoring for AF after a stroke, which is 24 hours as per the current recommended guidelines. Hence, determining the optimal duration of monitoring for paroxysmal atrial fibrillation after acute ischemic stroke remains a matter of debate. Multiple trials were published in regard to this matter using both invasive and noninvasive monitoring strategies for different monitoring periods. The data provided by these trials showcase strong evidence suggesting a longer monitoring strategy beyond 24 hours is associated with higher detection rates of AF, with the higher percentage of patients detected consequently receiving proper secondary stroke prevention with anticoagulation and thus justifying the cost-effectiveness of such measures. Overall, we thus conclude that increasing the monitoring duration for AF after a cryptogenic stroke to at least 72 hours will indeed enhance the detection rates, but the cost-effectiveness of this monitoring strategy compared to longer monitoring durations is yet to be established. PMID:27314027

  2. CTS Trials Network: Surgical ablation of atrial fibrillation during mitral valve surgery - many questions unanswered.

    PubMed

    Afifi, Ahmed

    2015-01-01

    A disease that is associated with stroke and mortality, atrial fibrillation (AF) complicates 30 to 50% of mitral valve disease patients admitted for surgery.(1) Since the introduction of the Cox maze III procedure in 1992 many efforts have been made to come up with modified lesion sets and/or energy sources to surgically treat AF. This lead to the recently published American Heart Association (AHA)- American College of Cardiology (ACC)-Heart Rhythm Society (HRS) guidelines(2) stating that it is reasonable to perform atrial fibrillation ablation in selected patients undergoing other types of cardiac surgery. The effectiveness of different techniques in conversion to sinus rhythm and the clinical impact of freedom from AF remain a question. The CTS Trials Network have undertaken a trial to answer these questions. The first year results of their randomized trial comparing AF ablation at the time of mitral valve surgery with mitral valve surgery alone were published recently in The New England Journal of Medicine.(3).

  3. CTS Trials Network: Surgical ablation of atrial fibrillation during mitral valve surgery - many questions unanswered

    PubMed Central

    Afifi, Ahmed

    2015-01-01

    A disease that is associated with stroke and mortality, atrial fibrillation (AF) complicates 30 to 50% of mitral valve disease patients admitted for surgery.1 Since the introduction of the Cox maze III procedure in 1992 many efforts have been made to come up with modified lesion sets and/or energy sources to surgically treat AF. This lead to the recently published American Heart Association (AHA)– American College of Cardiology (ACC)–Heart Rhythm Society (HRS) guidelines2 stating that it is reasonable to perform atrial fibrillation ablation in selected patients undergoing other types of cardiac surgery. The effectiveness of different techniques in conversion to sinus rhythm and the clinical impact of freedom from AF remain a question. The CTS Trials Network have undertaken a trial to answer these questions. The first year results of their randomized trial comparing AF ablation at the time of mitral valve surgery with mitral valve surgery alone were published recently in The New England Journal of Medicine.3 PMID:26566527

  4. Procainamide conversion of acute atrial fibrillation after open-heart surgery compared with digoxin treatment.

    PubMed

    Hjelms, E

    1992-01-01

    In 30 patients who developed atrial fibrillation after open-heart surgery the efficacy of intravenous procainamide was evaluated and compared with standard acute digoxin digitalisation. The patients were randomized to two groups of 15. One group received procainamide intravenously at a rate of 25 mg/min and with maximum dose 15 mg/kg. In the other group digoxin 0.75-1.0 mg was given intravenously according to renal function and body weight. Conversion to sinus rhythm occurred during or immediately after the infusion in 87% of the procainamide group, but only in 60% of the digoxin group (p < 0.05). The mean time from start of treatment to conversion was 40 min in the procainamide vs. 540 min in the digoxin group (p < 0.002). There were no serious complications of the procainamide treatment. Intravenous procainamide conversion of postoperative atrial fibrillation is concluded to be effective and safe and can be recommended as the treatment of first choice in awake and nonintubated postoperative cardiac patients. PMID:1287833

  5. Estrogen receptor 1 gene (TA)n polymorphism is associated with lone atrial fibrillation in men

    PubMed Central

    Golubić, Karlo; Šmalcelj, Anton; Sertić, Jadranka; Juričić, Ljiljana

    2014-01-01

    Aim To determine the association between the number of thymine-adenine (TA)n dinucleotide repeats in the promoter region of the gene coding for the estrogen receptor alpha (ESR1) and the prevalence of lone atrial fibrillation (AF) in men. Methods We conducted a case-control study involving 89 men with lone AF and 166 healthy male controls. The ESR1 genotype was established by polymerase chain reaction and capillary electrophoresis. To assess the association of ESR1 genotype with AF, logistic regression models were built with AF as outcome. Results Men with lone AF had significantly greater number of (TA)n repeats of single alleles than controls (mean ± standard deviation, 19.2 ± 4.2 vs 18 ± 4.3, P = 0.010). After adjustment for other factors, a unit-increase in (TA)n repeat number was associated with a significantly greater likelihood of AF (odds ratio 1.069; 95% confidence interval 1.024-1.116, P = 0.002). Conclusions Our results indicate that a greater number of (TA)n repeats in the promoter region of ESR1 is associated with a significantly increased likelihood of lone atrial fibrillation in men. PMID:24577825

  6. Atrial Fibrillation Due to Over The Counter Stimulant Drugs in A Young Adult

    PubMed Central

    Alagusundaramoorthy, Sayee Sundar; Agrawal, Abhinav

    2015-01-01

    The usage of over the counter stimulant drugs and energy drinks is increasing on a day to day basis for various purposes including work, sports and leisure among individuals in all age groups. Multiple formulations are available in the market including pills, liquid capsules and drinks in various flavours. Many of them contain excessively high doses of caffeine along with a variety of stimulant compounds that have multiple effects in different parts of the human body. The consumption of such high amounts of caffeine itself has shown to have caused cardiac arrhythmias in healthy individuals and when it is mixed with a number of stimulant compounds can be associated with a number of adverse effects in the human body. However, the awareness of such life threatening complications associated with these energy drinks does not exist among people who consume it on a day to day basis. We report a case of 25-year-old Caucasian male with no significant past medical history for cardiac diseases, no risk factors for atrial fibrillation, non smoker, occasional alcohol drinker who presents with new onset atrial fibrillation with rapid ventricular response due to the consumption of over the counter stimulant energy capsule which had high doses of caffeine. PMID:26435989

  7. Dilemmas in the management of atrial fibrillation in chronic kidney disease.

    PubMed

    Reinecke, Holger; Brand, Eva; Mesters, Rolf; Schäbitz, Wolf-Rüdiger; Fisher, Marc; Pavenstädt, Hermann; Breithardt, Günter

    2009-04-01

    Patients with chronic kidney disease (CKD) have an increased risk for cardiovascular morbidity and mortality. Little attention has been paid to the problem of atrial fibrillation, although this arrhythmia is very frequent with a prevalence of 13 to 27% in patients on long-term hemodialysis. Because of the large number of pathophysiologic mechanisms involved, these patients have a high risk for both thromboembolic events and hemorrhagic complications. Stroke is a frequent complication in CKD: The US Renal Data System reports an incidence of 15.1% in hemodialysis patients compared with 9.6% in patients with other stages of CKD and 2.6% in a control cohort without CKD. The 2-yr mortality rates after stroke in these subgroups were 74, 55, and 28%, respectively. Although oral coumadin is the treatment of choice for atrial fibrillation, its use in patients with CKD is reported only in limited studies, all in hemodialysis patients, and is associated with a markedly increased rate of bleeding compared with patients without CKD. With regard to the high risk for stroke and the conflicting data about oral anticoagulation, an individualized stratification algorithm is presented based on relevant studies.

  8. Alcohol Consumption as a Risk Factor for Atrial Fibrillation: a Systematic Review and Meta-Analysis

    PubMed Central

    Samokhvalov, Andriy V.; Irving, Hyacinth M.; Rehm, Jürgen

    2010-01-01

    Background Alcohol exposure is one of the major risk factors for global burden of disease, but atrial fibrillation (AF) had not yet been included in these estimates. The purpose of this contribution was to examine the dose-response relationship between alcohol consumption and AF and to explore potential causal pathways. Design and methods Systematic literature review and meta-analyses Results Overall, a consistent dose-response relationship between the amount of alcohol consumed daily and the probability of the onset of AF was found. Women consuming 24, 60, and 120 grams of alcohol daily had RRs of 1.07 (95% CI: 1.04,1.10), 1.42 (95% CI: 1.23,1.64) and 2.02 (95% CI: 1.60,2.97) respectively, relative to non-drinkers. Among men, the corresponding RRs were 1.08 (95% CI: 1.04,1.11), 1.44 (95% CI: 1.23,1.69) and 2.09 (95% CI: 1.52,2.86). Based on the categorical analyses, we could not exclude the existence of a threshold (3 drinks a day for men and 2 drinks a day for women). Several pathogenic mechanisms for the development of atrial fibrillation in alcohol users were identified. Conclusions Epidemiological criteria for causality were met to conclude a causal impact of alcohol consumption on the onset of AF with a monotonic dose-response relationship. However, the impact of light drinking is not clear. PMID:21461366

  9. Development of apixaban: a novel anticoagulant for prevention of stroke in patients with atrial fibrillation.

    PubMed

    Hanna, Michael S; Mohan, Puneet; Knabb, Robert; Gupta, Elora; Frost, Charles; Lawrence, John H

    2014-11-01

    The factor Xa inhibitor apixaban is one of the novel anticoagulants to emerge as alternatives to long-standing standards of care that include low-molecular-weight heparin and warfarin. The development of apixaban reflects a strategy to optimize the clinical pharmacology profile, dosing posology, trial designs, and statistical analyses across multiple indications, and to seek alignment with global health authorities. The primary objective of dose selection was to maintain balance between efficacy and bleeding risk. Twice-daily dosing of apixaban, rather than once daily, was chosen to lower peak concentrations and reduce fluctuations between peak and trough levels. Our discussion here focuses on the use of apixaban for stroke prevention in nonvalvular atrial fibrillation (NVAF). Supporting this indication, a pair of registrational trials was conducted that enrolled the full spectrum of patients who, by guidelines, were eligible for anticoagulation. In the AVERROES study of patients who were unsuitable for warfarin therapy, apixaban was superior to aspirin in reducing the risk of stroke or systemic embolism (SSE), without a significant increase in major bleeding (MB). In the ARISTOTLE (Apixaban for Reduction In STroke and Other ThromboemboLic Events in Atrial Fibrillation) study, apixaban was superior to warfarin on the rates of SSE, MB, and all-cause mortality. Overall, these studies have demonstrated a substantially favorable benefit-risk profile for apixaban over warfarin and aspirin in NVAF. PMID:25377080

  10. Usefulness of vernakalant hydrochloride injection for rapid conversion of atrial fibrillation.

    PubMed

    Pratt, Craig M; Roy, Denis; Torp-Pedersen, Christian; Wyse, D George; Toft, Egon; Juul-Moller, Steen; Retyk, Enrique; Drenning, David Humphrey

    2010-11-01

    The objective of the present study was to assess the safety and effectiveness of vernakalant hydrochloride injection (RSD1235), a novel antiarrhythmic drug, for the conversion of atrial fibrillation (AF) or atrial flutter to sinus rhythm (SR). Patients with either AF or atrial flutter were randomized in a 1:1 ratio to receive vernakalant (n = 138) or placebo (n = 138) and were stratified by an arrhythmia duration of >3 hours to ≤7 days (short duration) and 8 to ≤45 days (long duration). The first infusion of placebo or vernakalant (3 mg/kg) was given for 10 minutes followed by a second infusion of placebo or vernakalant (2 mg/kg) 15 minutes later if the arrhythmia had not terminated. A total of 265 patients were randomized and received treatment. The primary end point was conversion of AF to SR for ≥1 minute within 90 minutes of the start of the drug infusion in the short-duration AF group. Of the 86 patients receiving vernakalant in the short-duration AF group, 44 (51.2%) demonstrated conversion to SR compared to 3 (3.6%) of the 84 in the placebo group (p <0.0001). The median interval to conversion of short-duration AF to SR in the responders given vernakalant was 8 minutes. Of the entire AF population (short- and long-duration AF), 47 (39.8%) of the 118 vernakalant patients experienced conversion of AF to SR compared to 4 (3.3%) of the 121 placebo patients (p <0.0001). Transient dysgeusia and sneezing were the most common adverse events in the vernakalant patients. One vernakalant patient who had severe aortic stenosis experienced hypotension and ventricular fibrillation and died. In conclusion, vernakalant demonstrated a rapid and high rate of conversion for short-duration AF and was well tolerated. PMID:21029824

  11. Inducibility of human atrial fibrillation in an in silico model reflecting local acetylcholine distribution and concentration.

    PubMed

    Hwang, Minki; Lee, Hyun-Seung; Pak, Hui-Nam; Shim, Eun Bo

    2016-01-01

    Vagal nerve activity has been known to play a crucial role in the induction and maintenance of atrial fibrillation (AF). However, it is unclear how the distribution and concentration of local acetylcholine (ACh) promotes AF. In this study, we investigated the effect of the spatial distribution and concentration of ACh on fibrillation patterns in an in silico human atrial model. A human atrial action potential model with an ACh-dependent K(+) current (IKAch) was used to examine the effect of vagal activation. A simulation of cardiac wave dynamics was performed in a realistic 3D model of the atrium. A model of the ganglionated plexus (GP) and nerve was developed based on the "octopus hypothesis". The pattern of cardiac wave dynamics was examined by applying vagal activation to the GP areas or randomly. AF inducibility in the octopus hypothesis-based GP and nerve model was tested. The effect of the ACh concentration level was also examined. In the single cell simulation, an increase in the ACh concentration shortened APD90 and increased the maximal slope of the restitution curve. In the 3D simulation, a random distribution of vagal activation promoted wavebreaks while ACh secretion limited to the GP areas did not induce a noticeable change in wave dynamics. The octopus hypothesis-based model of the GP and nerve exhibited AF inducibility at higher ACh concentrations. In conclusion, a 3D in silico model of the GP and parasympathetic nerve based on the octopus model exhibited higher AF inducibility with higher ACh concentrations. PMID:26807030

  12. The serum matrix metalloproteinase-9 level is an independent predictor of recurrence after ablation of persistent atrial fibrillation

    PubMed Central

    Wu, Gang; Wang, Shun; Cheng, Mian; Peng, Bin; Liang, Jingjun; Huang, He; Jiang, Xuejun; Zhang, Lizhi; Yang, Bo; Cha, Yongmei; Jiang, Hong; Huang, Congxin

    2016-01-01

    OBJECTIVES: This study investigated whether the serum matrix metalloproteinase-9 level is an independent predictor of recurrence after catheter ablation for persistent atrial fibrillation. METHODS: Fifty-eight consecutive patients with persistent atrial fibrillation were enrolled and underwent catheter ablation. The serum matrix metalloproteinase-9 level was detected before ablation and its relationship with recurrent arrhythmia was analyzed at the end of the follow-up. RESULTS: After a mean follow-up of 12.1±7.2 months, 21 (36.2%) patients had a recurrence of their arrhythmia after catheter ablation. At baseline, the matrix metalloproteinase-9 level was higher in the patients with recurrence than in the non-recurrent group (305.77±88.90 vs 234.41±93.36 ng/ml, respectively, p=0.006). A multivariate analysis showed that the matrix metalloproteinase-9 level was an independent predictor of arrhythmia recurrence, as was a history of atrial fibrillation and the diameter of the left atrium. CONCLUSION: The serum matrix metalloproteinase-9 level is an independent predictor of recurrent arrhythmia after catheter ablation in patients with persistent atrial fibrillation. PMID:27276393

  13. An evidence-based review of edoxaban and its role in stroke prevention in patients with nonvalvular atrial fibrillation

    PubMed Central

    Acharya, Tushar; Deedwania, Prakash

    2015-01-01

    Atrial fibrillation is the most common arrhythmia in the elderly. It is responsible for significant morbidity and mortality from cardioembolic complications like stroke. As a result, atrial fibrillation patients are risk-stratified using the CHADS2 or CHA2DS2-VASc scoring systems. Those at intermediate-to-high risk have traditionally been treated with therapeutic anticoagulation with warfarin for stroke prevention. Although effective, warfarin use is fraught with multiple concerns, such as a narrow therapeutic window, drug–drug and drug–food interactions, and excessive bleeding. Novel oral anticoagulant agents have recently become available as viable alternatives for warfarin therapy. Direct thrombin inhibitor dabigatran and factor Xa inhibitors like rivaroxaban and apixaban have already been approved by the US Food and Drug Administration (FDA) for stroke prevention in patients with nonvalvular atrial fibrillation. Edoxaban is the latest oral direct factor Xa inhibitor studied in the largest novel oral anticoagulant trial so far: ENGAGE AF-TIMI 48. Treatment with a 30 mg or 60 mg daily dose of edoxaban was found to be noninferior to dose-adjusted warfarin in reducing the rate of stroke and systemic embolism in patients with nonvalvular atrial fibrillation, with a lower incidence of bleeding complications and cardiovascular deaths. Edoxaban was recently reviewed by an FDA advisory committee and recommended as a stroke-prophylaxis agent. Once approved, it promises to provide another useful alternative to warfarin therapy. PMID:26019695

  14. Norepinephrine and acetylcholine changes during electrically-induced atrial fibrillation episodes in canine models.

    PubMed

    Zhang, X; Zhang, Y; Gao, F; Zhang, F; Yang, Z; Ouyang, S; Rao, M; Hou, Y

    2016-01-01

    Atrial fibrillation (AF) is the most prevalent heart rhythm disorder, and autonomic nervous system (ANS) is important to AF. This study aims to identify whether changes in transmitters released by ANS could reflect their activities. The right atrium (RA) groups (1-40V) included RA500 and RA1000. While ANS groups received high-frequency electrical stimulation (1-8V, 20 Hz, 2 ms), including left stellate ganglion stimulation (LSGS) andleft cervical vagus trunk stimulation (LVTS). The induced rate of AF, duration and atrial effective refractory period (AERP) were measured. The blood was drawn for evaluation of norepinephrine (NE) and acetylcholine (Ach) concentrations. At 12-hours, RA tissue was dissected and compared against un-stimulated controls. While AF was induced by all groups, duration and AERP were significantly different between RA pacing groups and ANS-stimulated groups, respectively (P<0.05). Specific changes in profile of NE and Ach were associated with modality of stimulation. RA1000 tended to display most significant changes (P<0.05) compared to other groups while variables concentration levels were observed in other groups. In conclusion, electrically-induced AF initiated by various modalities of stimulation showed different changes in serum and RA tissues. Fast frequency pacing caused significant atrial electrical remodeling, including ANS activity change. PMID:27453277

  15. Ablation for atrial fibrillation during mitral valve surgery: 1-year results through continuous subcutaneous monitoring.

    PubMed

    Bogachev-Prokophiev, Alexandr; Zheleznev, Sergey; Romanov, Alexander; Pokushalov, Evgeny; Pivkin, Alexey; Corbucci, Giorgio; Karaskov, Alexander

    2012-07-01

    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

  16. Efficacy of circumferential pulmonary vein ablation of atrial fibrillation in endurance athletes

    PubMed Central

    Calvo, Naiara; Mont, Lluís; Tamborero, David; Berruezo, Antonio; Viola, Graziana; Guasch, Eduard; Nadal, Mercè; Andreu, David; Vidal, Barbara; Sitges, Marta; Brugada, Josep

    2010-01-01

    Aims Long-term endurance sport practice has been increasingly recognized as a risk factor for lone atrial fibrillation (AF). However, data on the outcome of circumferential pulmonary vein ablation (CPVA) in endurance athletes are scarce. The aim of the study was to evaluate the efficacy of CPVA in AF secondary to endurance sport practice. Methods and results Patients submitted to CPVA answered a questionnaire about lifetime history of endurance sport practice. Endurance athletes were defined as those who engaged in >3 h per week of high-intensity exercise for at least the 10 years immediately preceding their AF diagnosis. A series of 182 consecutive patients was included (51 ± 11 years, 65% with paroxysmal AF, 81% men, 42 ± 6 mm mean left atrial diameter); 107 (59%) patients had lone AF, and 42 of them (23% of the study population) were classified as endurance athletes (lone AF sport group). Freedom from arrhythmia after a single CPVA was similar in the lone AF sport group compared with the remaining patients (P = 0.446). Left atrial size and long-standing AF were the only independent predictors for arrhythmia recurrence after ablation. Conclusion Circumferential pulmonary vein ablation was as effective in AF secondary to endurance sport practice as in other aetiologies of AF. PMID:19923171

  17. Biomarkers and the prediction of atrial fibrillation: state of the art

    PubMed Central

    O’Neal, Wesley T; Venkatesh, Sanjay; Broughton, Stephen T; Griffin, William F; Soliman, Elsayed Z

    2016-01-01

    Atrial fibrillation (AF) is the most common sustained arrhythmia encountered in clinical practice, and it places a substantial burden on the health care system. Despite improvements in our understanding of AF pathophysiology, we have yet to develop targeted preventive therapies. Recently, numerous biological markers have been identified to aid in the prediction of future AF events. Subclinical markers of atrial stress, inflammation, endothelial dysfunction, kidney dysfunction, and atherosclerosis have been linked to AF. The connection between these markers and AF is the identification of subclinical states in which AF propagation is likely to occur, as these conditions are associated with abnormal atrial remodeling and fibrosis. Additionally, several risk scores have been developed to aid in the identification of at-risk patients. The practicing clinician should be aware of these subclinical markers, as several of these markers improve the predictive abilities of current AF risk scores. Knowledge of these subclinical markers also provides clinicians with a better understanding of AF risk factors, and the opportunity to reduce the occurrence of AF by incorporating well-known cardiovascular disease risk factor modification strategies. In this review, we highlight several novel biological markers that have improved our understanding of AF pathophysiology and appraise the utility of these markers to improve our ability to predict future AF events. PMID:27486329

  18. Catheter ablation of persistent atrial fibrillation: The importance of substrate modification

    PubMed Central

    Letsas, Konstantinos P; Efremidis, Michael; Sgouros, Nikolaos P; Vlachos, Konstantinos; Asvestas, Dimitrios; Sideris, Antonios

    2015-01-01

    Accumulating data have shown that elimination of atrial fibrillation (AF) sources should be the goal in persistent AF ablation. Pulmonary vein isolation, linear lesions and complex fractionated atrial electrograms (CFAEs) ablation have shown limited efficacy in patients with persistent AF. A combined approach using voltage, CFAEs and dominant frequency (DF) mapping may be helpful for the identification of AF sources and subsequent focal substrate modification. The fibrillatory activity is maintained by intramural reentry centered on fibrotic patches. Voltage mapping may assist in the identification of fibrotic areas. Stable rotors display the higher DF and possibly drive AF. Furthermore, the single rotor is usually consistent with organized AF electrograms without fractionation. It is therefore quite possible that rotors are located at relatively “healthy islands” within the patchy fibrosis. This is supported by the fact that high DF sites have been negatively correlated to the amount of fibrosis. CFAEs are located in areas adjacent to high DF. In conclusion, patchy fibrotic areas displaying the maximum DF along with high organization index and the lower fractionation index are potential targets of ablation. Prospective studies are required to validate the efficacy of substrate modification in left atrial ablation outcomes. PMID:25810810

  19. I(Kur)/Kv1.5 channel blockers for the treatment of atrial fibrillation.

    PubMed

    Tamargo, Juan; Caballero, Ricardo; Gómez, Ricardo; Delpón, Eva

    2009-04-01

    Atrial fibrillation (AF) is the most common sustained arrhythmia. Anti-arrhythmic drugs remain the mainstay of therapy, but the available class I and III anti-arrhythmic drugs are only moderately effective in long-term restoring/maintaining sinus rhythm (SR) and can produce potentially fatal ventricular pro-arrhythmia. In an attempt to identify safer and more effective anti-arrhythmic drugs, drug discovery efforts have focused on 'atrial selective drugs' that target cardiac ion channel(s) that are exclusively or predominantly expressed in the atria. The ultra-rapid activating delayed rectifier K(+) current (I(Kur)), carried by Kv1.5 channels, is a major repolarizing current in human atria, but seems to play no role in the ventricle. This finding offers the possibility of developing selective I(Kur) blockers to restore and maintain SR without a risk of ventricular pro-arrhythmia. Several I(Kur) blockers are now being developed but clinical data are still limited, so the precise role of these agents in the treatment of AF remains to be defined. In this review we analyze the possible advantages and disadvantages of the developmental I(Kur) blockers as they represent the first step for the development of potential atrial selective drugs for a more effective and safer treatment and prevention of AF.

  20. Impact of tissue geometry on simulated cholinergic atrial fibrillation: A modeling study

    NASA Astrophysics Data System (ADS)

    Comtois, Philippe; Nattel, Stanley

    2011-03-01

    Atrial fibrillation (AF), arising in the cardiac atria, is a common cardiac rhythm disorder that is incompletely understood. Numerous characteristics of the atrial tissue are thought to play a role in the maintenance of AF. Most traditional theoretical models of AF have considered the atrium to be a flat two-dimensional sheet. Here, we analyzed the relationship between atrial geometry, substrate size, and AF persistence, in a mathematical model involving heterogeneity. Spatially periodic properties were created by variations in times required for reactivation due to periodic acetylcholine concentration [ACh] distribution. The differences in AF maintenance between the sheet and the cylinder geometry are found for intermediate gradients of inexcitable time (intermediate [ACh]). The maximum difference in AF maintenance between geometry decreases with increasing tissue size, down to zero for a substrate of dimensions 20 × 10 cm. Generators have the tendency to be anchored to the regions of longer inexcitable period (low [ACh]). The differences in AF maintenance between geometries correlate with situations of moderate anchoring for which rotor-core drifts between low-[ACh] regions occur, favoring generator disappearance. The drift of generators increases their probability of disappearance at the tissue borders, resulting in a decreased maintenance rate in the sheet due to the higher number of no-flux boundaries. These interactions between biological variables and the role of geometry must be considered when selecting an appropriate model for AF in intact hearts.

  1. A proposal for new clinical concepts in the management of atrial fibrillation.

    PubMed

    Camm, A John; Al-Khatib, Sana M; Calkins, Hugh; Halperin, Jonathan L; Kirchhof, Paulus; Lip, Gregory Y H; Nattel, Stanley; Ruskin, Jeremy; Banerjee, Amitava; Blendea, Dan; Guasch, Eduard; Needleman, Matthew; Savelieva, Irina; Viles-Gonzalez, Juan; Williams, Eric S

    2012-09-01

    Atrial fibrillation (AF) represents a growing public health burden. It is a complex condition, involving a number of etiologic factors and arrhythmia mechanisms associated with atrial remodeling. Greater understanding of these mechanisms may improve therapy. Current AF classification schemes are limited by simplicity. A number of risk factors predict AF onset, and additional factors are being evaluated in registry studies. Doppler imaging and Holter monitoring in high-risk patients to predict the onset of AF and progression from paroxysmal to permanent AF are promising. There is a need for a novel multifactorial classification model encompassing AF duration, symptoms, markers of atrial remodeling, and a risk score for AF onset, persistence, progression, and complications to guide treatment and prognostication. Preventing AF onset with upstream therapy is of great interest, but current data are conflicting. More study is needed to optimize rhythm control with antiarrhythmic drugs and targeted ablation to specific patient populations at an earlier stage. There is little consensus on optimal rate control and no information relating to optimum rate control in specific populations. This article highlights new concepts in AF and directions for future research.

  2. Age-related changes in cellular electrophysiology and calcium handling for atrial fibrillation

    PubMed Central

    Xu, Guo-Jun; Gan, Tian-Yi; Tang, Bao-Peng; Chen, Zu-Heng; Jiang, Tao; Song, Jian-Guo; Guo, Xia; Li, Jin-xin

    2013-01-01

    This study was to investigate whether or not the dysfunction of atrial repolarization and abnormality of the intracellular Ca2+ handling protein was augmented with ageing. Four groups of dogs were studied, adult and aged dogs in sinus rhythm (SR) and atrial fibrillation (AF) induced by rapid atrial pacing. We used whole cell patch clamp recording techniques to measure L-type Ca2+ current in cardiomyocytes dispersed from the left atria. Expressions of the Ca2+ handling protein were measured by real-time quantitative reverse transcription-polymerase chain reaction and Western blot methods. Cardiomyocytes from old atria showed longer action potential (AP) duration to 90% repolarization, lower AP plateau potential and peak L-type Ca2+ current densities at both age groups in SR. AF led to a higher maximum diastolic potential, an increase of amplitude of phase 0, decreases of AP duration to 90% repolarization, plateau potential and peak L-type Ca2+ current densities. Compared to the adult group, mRNA and protein expressions of the L-type calcium channel a1c were decreased, whereas expressions of calcium adenosine triphosphatase were increased in the aged group. Compared to SR group, expressions of Ca2+ handling protein except for phospholamban were significantly decreased in both age groups with AF. We conclude that these ageing-induced electrophysiological and molecular changes showed that general pathophysiological adaptations might provide a substrate conducive to AF. PMID:23837844

  3. [Consensus statement: Management of oral anticoagulation for stroke prevention in patients with nonvalvular atrial fibrillation].

    PubMed

    Helms, Thomas Maria; Silber, Sigmund; Schäfer, Andreas; Masuhr, Florian; Palm, Frederick; Darius, Harald; Schrör, Karsten; Bänsch, Dietmar; Bramlage, Peter; Hankowitz, Johannes; Karle, Christoph A; Stargardt, Tom; Weil, Joachim; Geller, Johann Christoph

    2016-09-01

    With the introduction of edoxaban last year in Germany, four nonvitamin K antagonist oral anticoagulants are now available for stroke prevention in patients with nonvalvular atrial fibrillation. These novel oral anticoagulants (NOAC) represent an attractive new option compared to vitamin K antagonists (e.g., warfarin or phenprocoumon) due to simple use and fewer interactions with other drugs or food. Therefore, no INR monitoring and dosage adjustments are required for NOAC. The compelling clinical advantage of NOAC is the dramatic risk reduction of hemorhagic stroke and intracranial bleeding compared to current standard. In addition, total mortality is significantly reduced by 10 %. These effects are demonstrated for all four NOAC (dabigatran, rivaroxaban, apixaban and edoxaban). Therefore, current national and international guidelines recommend NOAC as the preferred option or at least as an attractive alternative compared to the former standard of vitamin K antagonists. The economic impact and reimbursement by Statutory Health Insurance (GKV) is of major importance for treatment in an outpatient setting. For apixaban and edoxaban, an additional benefit was granted by the institution of G‑BA and IQWiG in this clinical setting, whereas dabigatran and rivaroxaban were not assessed due to market entrance prior to 2011 before the AMNOG procedure was initiated. The members of this consensus paper recommend NOAC as the preferred option for patients with nonvalvular atrial fibrillation who are currently not treated with anticoagulant drugs in spite of clear indication for anticoagulation. For new patients with nonvalvular fibrillation, it should be decided on an individual basis which treatment option is adequate for the patient with their respective comorbidities. PMID:27576696

  4. Targeting Inflammation and Oxidative Stress in Atrial Fibrillation: Role of 3-Hydroxy-3-Methylglutaryl-Coenzyme A Reductase Inhibition with Statins

    PubMed Central

    Pinho-Gomes, Ana Catarina; Reilly, Svetlana; Brandes, Ralf P.

    2014-01-01

    Abstract Significance: Atrial fibrillation (AF) is a burgeoning health-care problem, and the currently available therapeutic armamentarium is barely efficient. Experimental and clinical evidence implicates inflammation and myocardial oxidative stress in the pathogenesis of AF. Recent Advances: Local and systemic inflammation has been found to both precede and follow the new onset of AF, and NOX2-dependent generation of reactive oxygen species in human right atrial samples has been independently associated with the occurrence of AF in the postoperative period in patients undergoing cardiac surgery. Anti-inflammatory and antioxidant agents can prevent atrial electrical remodeling in animal models of atrial tachypacing and the new onset of AF after cardiac surgery, suggesting a causal relationship between inflammation/oxidative stress and the atrial substrate that supports AF. Critical Issues: Statin therapy, by redressing the myocardial nitroso-redox balance and reducing inflammation, has emerged as a potentially effective strategy for the prevention of AF. Evidence indicates that statins prevent AF-induced electrical remodeling in animal models of atrial tachypacing and may reduce the new onset of AF after cardiac surgery. However, whether statins have antiarrhythmic properties in humans has yet to be conclusively demonstrated, as data from randomized controlled trials specifically addressing the relevance of statin therapy for the primary and secondary prevention of AF remain scanty. Future Directions: A better understanding of the mechanisms underpinning the putative antiarrhythmic effects of statins may afford tailoring AF treatment to specific clinical settings and patient's subgroups. Larg