Atrial fibrillation in recipients of cardiac resynchronization therapy device: 1-year results of the randomized MASCOT trial

• Published in: The American heart journal Vol. 156; no. 3; pp. 520 - 526
• Main Authors: Padeletti, Luigi, MD, Muto, Carmine, MD, Maounis, Themistoclis, MD, Schuchert, Andreas, MD, Bongiorni, Maria-Grazia, MD, Frank, Robert, MD, Vesterlund, Thomas, MD, Brachmann, Johannes, MD, Vicentini, Alfredo, MD, Jauvert, Gaël, MD, Tadeo, Giorgio, MD, Gras, Daniel, MD, Lisi, Francesco, MD, Dello Russo, Antonio, MD, Rey, Jean-Luc, MD, Boulogne, Eric, MS, Ricciardi, Giuseppe, MD
• Format: Journal Article
• Language: English
• Published: New York, NY Mosby, Inc 01-09-2008; Elsevier; Elsevier Limited
• Subjects: Aged; Algorithms; Atrial Fibrillation - epidemiology; Atrial Fibrillation - mortality; Atrial Fibrillation - prevention & control; Atrial Function; Biological and medical sciences; Cardiac arrhythmia; Cardiac dysrhythmias; Cardiac Pacing, Artificial - adverse effects; Cardiac Pacing, Artificial - methods; Cardiology. Vascular system; Cardiovascular; Drug therapy; Female; Follow-Up Studies; Heart; Heart attacks; Heart Failure - mortality; Heart Failure - therapy; Humans; Incidence; Male; Medical sciences; Middle Aged; Mortality; Pacemaker, Artificial; Prostheses and Implants; Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects); Single-Blind Method; Stroke Volume; Treatment Outcome; Ventricular Function; Cardiac resynchronization; Prognosis; Arrhythmia; Device; Atrial fibrillation; Instrumentation therapy; Cardiovascular disease; Long term; Excitability disorder; Instrumental stimulation; Randomization; Heart disease; Circulatory system; Cardiology
• ISSN: 0002-8703; 1097-6744
• DOI: 10.1016/j.ahj.2008.04.013

Background Atrial fibrillation (AF) is associated with increased morbidity and mortality in patients suffering from heart failure (HF). Patients in New York Heart Association HF classes III or IV, with systolic dysfunction and a wide QRS, are candidates for cardiac resynchronization therapy (CRT), and might benefit from atrial overdrive pacing (AOP). Methods The Management of Atrial fibrillation Suppression in AF-HF COmorbidity Therapy (MASCOT) trial enrolled 409 CRT device recipients (79% men), who were randomly assigned to AOP ON (n = 197), versus AOP OFF (n = 197) and followed up for 1 year. Their mean age was 68 ± 10 years, left ventricular ejection fraction 25 ± 6%, QRS duration 163 ± 29 milliseconds. New York Heart Association class III was present in 86% of patients and 19% had a history of paroxysmal AF. The primary study end point was incidence of permanent AF at 1 year. Results Atrial overdrive pacing increased the percentage of atrial pacing from 30% to 80% ( P < .0001), was well tolerated, and did not interfere with ( a ) delivery of CRT (95% mean ventricular pacing in both groups), ( b ) response to CRT (70% responders in the control vs 67% in the treatment group), or ( c ) cardiac function (left ventricular ejection fraction increased from 24.5% ± 6.2% to 32.7% ± 10.9% in the control and from 25.8% ± 6.8% to 33.1% ± 12.6% in the treatment group). The incidence of permanent AF was 3.3% in both groups. By logistic regression analysis, a history of AF ( P < .001) and absence of antiarrhythmic drugs ( P = .002) were associated with permanent AF. Conclusions In this first trial of a specific AF prevention algorithm in CRT recipients, AOP was safe and did not worsen HF. The prevention algorithm did not lower the 1-year incidence of AF.