Defibrillation In Heart Failure Trial Research Articles

Cost-effectiveness of cardiac resynchronisation therapy for patients with moderate-to-severe heart failure: a lifetime Markov model

ObjectiveTo assess the cost-effectiveness of cardiac resynchronisation therapy (CRT) both with CRT-P (biventricular pacemaker only) and with CRT-D (biventricular pacemaker with defibrillator) in patients with New York Heart Association (NYHA)...

Impact of Cardiac Resynchronization Therapy on Exercise Performance, Functional Capacity, and Quality of Life in Systolic Heart Failure With QRS Prolongation: COMPANION Trial Sub-Study

Background A total of 405 participants in the Comparison of Medical Therapy, Pacing, and Defibrillation in Heart Failure trial were prospectively enrolled in an exercise sub-study designed to study the influence of cardiac resynchronization therapy (CRT) on measures of exercise capacity, functional capacity, and quality of life (QOL). Methods and Results Substudy eligibility included New York Heart Association (NYHA) functional Class III or IV heart failure, left ventricular ejection fraction ≤0.35, QRS interval of ≥120 ms, normal sinus rhythm, a heart failure hospitalization (or equivalent) within 1 year, a peak VO 2 ≤22 mL ·kg ·min, the ability to walk 150 to 425 meters in 6 minutes, forced expiratory volume in 1 second/forced vital capacity ≥50%, and no clinical indication for a pacemaker or implantable cardioverter-defibrillator. Patients were randomized in a 1:4 ratio to optimal medical therapy (OPT) or to OPT plus CRT. Cardiopulmonary exercise testing (peak VO 2 and 6-minute walk distance [6MWD]) and assessment of NYHA functional class and QOL were assessed at baseline and at 3 and 6 months of assigned therapy. There was no significant improvement in peak VO 2 at 6 months in the CRT group compared with the OPT group (+0.63 mL ·kg ·min) by unadjusted analysis ( P = .05) or by analyses adjusted for missing data. Thus the primary end point of the study was not met. There was significantly greater improvement in the 6MWD in the CRT group compared with the OPT group at both 3 and 6 months by both statistical methods ( P ≤ .045). Likewise, a greater proportion of CRT patients improved by 1 or more NYHA functional classes ( P < .01) at 3 months and had better QOL scores ( P < .01) at 3 and 6 months compared with the OPT patients. Baseline peak VO 2 predicted clinical events (time to death, time to death or first hospitalization, or time to death and first heart failure hospitalization: P < .05) in CRT participants. Conclusion CRT patients with moderate to advanced symptoms of systolic heart failure and prolonged QRS intervals benefit from the addition of CRT to OPT in terms of exercise capacity, functional status, and QOL. CRT should be considered standard therapy in this select group of heart failure patients.

Current role of device therapy to reduce sudden cardiac death in heart failure

Sudden cardiac death (SCD) continues to be a major contributor to mortality in patients with heart failure (HF) despite recent advances in medical therapy. Device therapy, including the implantable cardioverter defibrillator (ICD) and cardiac resynchronization therapy (CRT), serves as an adjunct in reducing HF mortality. Several clinical trials support the prophylactic use of the ICD in reducing mortality in certain HF populations and have established the clinical benefits of CRT in advanced HF. More recently, the Comparison of Medical Therapy Pacing and Defibrillation in Heart Failure trial was the first study to demonstrate a survival benefit of CRT alone or in conjunction with an ICD. This article reviews the most pertinent data regarding the role of device therapy in reducing SCD in HF and addresses future challenges faced by device manufacturers and clinicians.