Thursday, December 11, 2008

Atrial Fibrillation: a Patient’s Guide to Understanding Drug Therapy


Citation : Ragini Bhakta.Atrial Fibrillation: a Patient’s Guide to Understanding Drug Therapy .JAFIB.2008 Dec;Volume 1 Issue(4): 255-256.

Atrial Fibrillation (AF) as defined by the American Heart Association is an irregular heart beat (rhythm) where the small upper chambers of the heart (atria) beat ineffectively. The atria cannot pump all of the blood out of the chambers, resulting in pooling of the blood or clot formation. Unfortunately, if a part of the clot leaves the atria, it can become lodged in an artery in the brain resulting in an ischemic stroke.

The A That Did Not Fib: Two Roads Both Traveled By


Citation : James C. Hansen,Abraham G. Kocheril.The A That Did Not Fib: Two Roads Both Traveled By .JAFIB.2008 Dec;Volume 1 Issue(4): 250-254.

Case: A 64-year-old woman presented with palpitations. Her 24-hour Holter monitor revealed runs of presumed atrial fibrillation (AF). The patient was referred for EP study and AF ablation.

EPS: At EPS, an anterograde A-H jump was noted. Spontaneous bursts of tachycardia were seen, consisting of sinus atrial beats with dual ventricular responses, each preceded by a His deflection. There was no atrial fibrillation during the study. Radiofrequency ablation of the slow AV node pathway was performed. There were no inducible tachycardias and no A-H jump following the ablation. The patient had no recurrence post-procedure.

Discussion: This case presents a rare example of simultaneous dual anterograde AV-nodal conduction. The conditions leading to this phenomenon include dual AVN pathways, markedly slowed conduction in the slow pathway, and lack of retrograde conduction up either pathway such that reentry was impossible. An irregular, narrow-complex tachycardia resulted, initially interpreted as AF. Slow-pathway ablation was curative.

The Anticoagulated Atrial Fibrillation Patient Who Requires “Curative” Therapy for Prostate Carcinoma: a Bleeding Conundrum


Citation : James A.Reiffel.The Anticoagulated Atrial Fibrillation Patient Who Requires “Curative” Therapy for Prostate Carcinoma: a Bleeding Conundrum .JAFIB.2008 Dec;Volume 1 Issue(4): 248-249.

With the aging of the population, the incidence of both prostate carcinoma (PCa) and atrial fibrillation (AF) has increased. Options for “curative therapy” PCa now include surgery, external beam radiation (EBT), and radioactive seed implantation (RSI). The latter two approaches, especially EBT, can produce radiation proctitis (RP) with rectal bleeding (RB). This poses an issue for anticoagulating the elderly AF patient who develops PCa. The attached case report of a 77 year old male who was treated with a combination of RSI and “low dose” EBT followed by recurrent severe rectal bleeding demonstrates the significance of this problem. In the AF patient with a CHADS2 score of 2 or more, and hence an indication for chronic warfarin therapy, the therapy of subsequently detected PCa requires careful consideration of the risks associated with its therapeutic options.

Is Rhythm Control with Pulmonary Vein Isolation Superior to Rate Control with AV Nodal Ablation in Patients with Heart Failure?


Citation : Dhanunjaya Lakkireddy.Is Rhythm Control with Pulmonary Vein Isolation Superior to Rate Control with AV Nodal Ablation in Patients with Heart Failure? .JAFIB.2008 Dec;Volume 1 Issue(4): 246-247.

BACKGROUND: Pulmonary-vein isolation is increasingly being used to treat atrial fibrillation in patients with heart failure. METHODS: In this prospective, multicenter clinical trial, we randomly assigned patients with symptomatic, drug-resistant atrial fibrillation, an ejection fraction of 40% or less, and New York Heart Association class II or III heart failure to undergo either pulmonary-vein isolation or atrioventricular-node ablation with biventricular pacing. All patients completed the Minnesota Living with Heart Failure questionnaire (scores range from 0 to 105, with a higher score indicating a worse quality of life) and underwent echocardiography and a 6-minute walk test (the composite primary end point). Over a 6-month period, patients were monitored for both symptomatic and asymptomatic episodes of atrial fibrillation. RESULTS: In all, 41 patients underwent pulmonary-vein isolation, and 40 underwent atrioventricular-node ablation with biventricular pacing; none were lost to follow-up at 6 months. The composite primary end point favored the group that underwent pulmonary-vein isolation, with an improved questionnaire score at 6 months (60, vs. 82 in the group that underwent atrioventricular-node ablation with biventricular pacing; P<0.001), a longer 6-minute-walk distance (340 m vs. 297 m, P<0.001), and a higher ejection fraction (35% vs. 28%, P<0.001). In the group that underwent pulmonary-vein isolation, 88% of patients receiving antiarrhythmic drugs and 71% of those not receiving such drugs were free of atrial fibrillation at 6 months. In the group that underwent pulmonary-vein isolation, pulmonary-vein stenosis developed in two patients, pericardial effusion in one, and pulmonary edema in another; in the group that underwent atrioventricular-node ablation with biventricular pacing, lead dislodgment was found in one patient and pneumothorax in another. CONCLUSIONS: Pulmonary-vein isolation was superior to atrioventricular-node ablation with biventricular pacing in patients with heart failure who had drug-refractory atrial fibrillation. (ClinicalTrials.gov number, NCT00599976.) 2008 Massachusetts Medical Society

Do Statins Decrease the Arrhythmia Burden in Patients with Paroxysmal Atrial Fibrillation?


Citation : Dhanunjaya Lakkireddy.Do Statins Decrease the Arrhythmia Burden in Patients with Paroxysmal Atrial Fibrillation? .JAFIB.2008 Dec;Volume 1 Issue(4): 244-245.


Role of the Autonomic Nervous System in the Creation of Substrate for Atrial Fibrillation


Citation : Rishi Arora,Alan H. Kadish.Role of the Autonomic Nervous System in the Creation of Substrate for Atrial Fibrillation .JAFIB.2008 Dec;Volume 1 Issue(4): 236-243.

Atrial fibrillation (AF) is the most common sustained arrhythmia disturbance and is associated with significant morbidity and mortality. In recent years, the pulmonary veins (PVs) and posterior left atrium (PLA) have been shown to play a significant role in the genesis of AF.


These regions have been shown to possess unique structural, electrophysiological and calcium (Ca2+) handling characteristics, all of which appear to contribute to substrate for AF.


The pathophysiology of AF is complex, and several mechanisms have been thought to contribute to the electrophysiologic and structural substrate for this arrhythmia. These mechanisms include fibrosis, stretch, inflammation and oxidative stress. In addition, neurohumoral factors have also been invoked for their possible contribution to the creation of electrophysiologic substrate for AF [3, 4]. An important neurohumoral factor that has been studied fairly extensively for its involvement in AF is the autonomic nervous system.

Typical flutter ablation as an adjunct to catheter ablation of atrial fibrillation


Citation : Dipen Shah.Typical flutter ablation as an adjunct to catheter ablation of atrial fibrillation .JAFIB.2008 Dec;Volume 1 Issue(4): 230-235.

Typical atrial flutter and atrial fibrillation are frequently observed to coexist(1) . In the current context of interventional electrophysiology, curative or at least definitive ablation is available for both arrhythmias. Despite their coexistence, it is not clear whether typical flutter ablation is necessary in all patients undergoing catheter ablation of atrial fibrillation. The following review explores the pathophysiology of both arrhythmias, their interrelationships and the available data pertaining to this theme.

Catheter Ablation for AF: Past, Present, and Future


Citation : David Spragg,Hugh Calkins.Catheter Ablation for AF: Past, Present, and Future .JAFIB.2008 Dec;Volume 1 Issue(4): 221-229.

Atrial fibrillation (AF) is the most common sustained tachyarrhythmia encountered by physicians. The prevalence of AF in patients over the age of 65 is approximately 6%, and approaches 10% in patients over the age of 85. As the median age of the population in the United States becomes older, the epidemiologic burden of AF in this country will likely increase. Currently approximately 2.2 million people in the United States have AF. AF, while typically not a life-threatening arrhythmia per se, is associated with increased risk of stroke, heart failure, and increased mortality. The stroke risk in patients with AF, for instance, is increased between 5- and 7-fold compared to similar patients without AF.

Periablative Anticoagulation Strategies in Patients with Atrial Fibrillation


Citation : Fernanda d’Araujo Costa Ferreira, Eduardo B. Saad.Periablative Anticoagulation Strategies in Patients with Atrial Fibrillation .JAFIB.2008 Dec;Volume 1 Issue(4): 216-220.

Atrial fibrillation is associated with thromboembolic events that may cause important impairment on quality of life. Pulmonary vein isolation is the treatment of choice in cases that are refractory to medical therapy. Once sheaths and catheters are manipulated inside the left atrium, anticoagulation with heparin must be used during the procedure to protect patients from thromboembolic phenomena. Different strategies of anticoagulation are used at different centers. This review summarizes the pathophysiology of thrombus formation in the left atrium, defines which patients are under high risk and describes the main strategies used for anticoagulation.


Extraatrial Disease in Patients with “Lone” Atrial Fibrillation


Citation : Jason Confino,Daniel Edmundowicz,Joan M. Lacomis,Iclal Ocak, Christopher R. Deible,David Schwartzman.Extraatrial Disease in Patients with “Lone” Atrial Fibrillation .JAFIB.2008 Dec;Volume 1 Issue(4): 209-215.

Aims: Lone atrial fibrillation (LAF) is considered by some to be a primary atrial electrophysiologic disorder. However, we have frequently observed evidence of “extraatrial” diseases - atherosclerosis and associated metabolic disorders - in our LAF patients. We sought to characterize and quantify extraatrial disease burden in LAF patients, and to correlate this burden with features of the arrhythmia including pattern (paroxysmal versus persistent) and response to catheter ablation.

Methods and Results: Forty-six consecutive patients with non-familial LAF underwent assessment for evidence of atherosclerosis (computed tomographic vascular calcification and elevated arterial pulse wave velocity) and associated metabolic diseases (dyslipidemia, insulin resistance and inflammation), and then catheter ablation.

The cohort had a significant incidence of atherosclerosis (57%) and metabolic (70%) diseases. Patients with persistent AF tended to have a greater extraatrial disease burden than those with paroxysmal AF. A significant inverse relationship between the rate of ablation success and extraatrial disease burden was demonstrated.

Conclusions: Extraatrial disease was common in this LAF cohort. Correlations between extraatrial disease burden and features of the arrhythmia would, if verified, challenge the notion that LAF is a “primary” electrophysiologic disorder.

Quality of Life, Exercise Capacity and Comorbidity in Old Patients with Permanent Atrial Fibrillation


Citation :Inger Ariansen,Knut Gjesdal, Michael Abdelnoor, Elisabeth Edvardsen, Steve Enger, Arnljot Tveit.Quality of Life, Exercise Capacity and Comorbidity in Old Patients with Permanent Atrial Fibrillation .JAFIB.2008 Dec;Volume 1 Issue(4): 202-208.

Background: The impact of atrial fibrillation (AF) on quality of life (QoL) differs with the AF population studied and is influenced by comorbidity. In hospital-based studies younger and highly symptomatic patients may be overrepresented. We performed an observational cross sectional study in two municipalities, comparing 75 year-old patients with and without permanent atrial fibrillation, with respect to health-related QoL and exercise capacity, with adjustment for the effects of confounders.
Methods: Maximal treadmill exercise testing provided peak oxygen uptake (VO2 peak). Health-related QoL was assessed by self-completed SF-36 questionnaires. The lowest quartile identified poor outcomes.
Results: 27 subjects with permanent AF and 71 subjects in sinus rhythm participated. AF patients had higher prevalence of compensated chronic heart failure (p < 0.001), valvular heart disease (p < 0.001), lower mean VO2 peak (22.7 ± 5.5 vs. 28.6 ± 6.3 ml/kg/min; p < 0.001), and more often poor VO2 peak; crude OR 5.3 (95%CI 1.8, 15.3), adjusted OR 7.5 (2.0, 28.3). Median Physical Component Summary score (with 25th and 75th percentile) was 41 (31, 51) in AF vs. 52 (45, 55) in controls (p < 0.001). Furthermore, the AF group had higher odds for poor physical QoL scores; crude OR 5.0 (1.8, 13.7), adjusted OR 4.3 (1.5, 12.4). Median Mental Component Summary score was 56 (42, 61) in the AF group vs. 57 (51, 60) in controls (p=0.565). The AF group had non-significantly increased odds for poor mental QoL scores; crude OR 2.3 (0.8, 6.2), adjusted OR 2.8 (1.0, 8.4).
Conclusion: Also after adjustment for confounders, older patients with permanent AF had higher odds for poor exercise capacity and poor physical QoL compared to subjects in sinus rhythm.


Leukocyte Atrial Fibrillation Filtration Study


Citation : Albert H. O-Yurvati, Steven Rodriguez, Glen Bell,Damon Kennedy, Robert T. Mallet.Leukocyte Atrial Fibrillation Filtration Study .JAFIB.2008 Dec;Volume 1 Issue(4): 194-201.

Abstract

Purpose: Atrial fibrillation remains the leading postoperative complication following cardiopulmonary bypass. A randomized trial was undertaken to evaluate the effectiveness of leukocyte filtration and aprotinin, applied separately and in combination, on the incidence of post-operative atrial fibrillation. A secondary component of the study was the impact of these adjunct interventions on post-surgical renal and neurological dysfunction.

Methods: A total of 1,220 patients undergoing primary isolated coronary artery bypass grafting were randomly assigned to one of four treatment groups. The control group (305 patients) received standard cardiopulmonary bypass with moderately hypothermic (34ÂșC) cardioplegic arrest. In the filtration group (310 patients) leukocyte reducing filters were incorporated into the bypass circuit. The aprotinin group (285 patients) received full Hammersmith dose aprotinin. The combination therapy group (320 patients) received both aprotinin and leukocyte filtration.

Results: The incidences of atrial fibrillation were 25% in the control group, 16% in the filtration group, 19% in the aprotinin group and 10% in the combination therapy group (P < style=""> Renal dysfunction was detected in 3% of the control group, 2% of the filtration group, 8% of the aprotinin group, and 5% of the combination group (P < style=""> Neurological dysfunction occurred in 2% of the control group, 2% of the filtration group, 1% of the aprotinin group, and 2% of the combination group (P = n.s.).

Conclusions: Combination therapy with aprotinin and leukocyte filtration markedly reduced atrial fibrillation post-cardiopulmonary bypass, and was more effective than the individual treatments. Aprotinin treatment increased the incidence of renal dysfunction, and the addition of leukocyte filtration partially mitigated this detrimental effect of aprotinin.