title: Comparison of clinical trials evaluating cardiac resynchronization therapy in mild to moderate heart failure.
abstract: Recently, three large randomized clinical trials: REVERSE, MADIT-CRT, and RAFT were completed aiming to determine the effects of cardiac resynchronization therapy (CRT) or CRT with defibrillator (CRT-D) in less advanced, predominantly NYHA class II heart failure (HF) patients. The REVERSE trial, significantly smaller than the other two trials, could be considered as a phase II study indicating that mild-to-moderate HF patients show symptomatic and hemodynamic improvement in response to CRT. The MADIT-CRT and RAFT are considered as definitive trials with large patient populations of about 1,800 patients each, and HF event/hospitalization or death as the primary endpoint. Both trials showed a significant reduction in the risk of primary endpoints: a 34% reduction in MADIT-CRT and 25% reduction in RAFT. However, RAFT also showed a significant reduction in mortality which was not observed in MADIT-CRT. The clinical characteristics of patients studied in both trials were different despite somewhat similar entry criteria. RAFT enrolled more advanced HF patients (including 20% NYHA class III patients) than MADIT-CRT. In the CRT-D arm, RAFT patients had about 20% two-year mortality in comparison to approximately 6% two-year mortality in MADIT-CRT. Mortality in RAFT was in similar to those observed in CRT-D patients in the COMPANION trial (estimated 25% two-year mortality), and in the CRT arm of the CARE-HF trial (estimated 18% two-year mortality), both older studies which enrolled NYHA class III and IV HF patients. Based on the above comparison, one could conclude that RAFT enrolled moderate-to-advanced HF patients whereas MADIT-CRT enrolled truly mild-to-moderate patients.
authors.affiliation: Cardiology Division, University of Rochester Medical Center, Rochester, New York 14642, USA. wojciech_zareba@urmc.rochester.edu
authors.forename: Wojciech
authors.initials: W
authors.lastname: Zaręba
mesh_terms: D058406:Cardiac Resynchronization Therapy / Q000009:adverse effects / Q000401:mortality; D019317:Evidence-Based Medicine; D006333:Heart Failure / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D006439:Hemodynamics; D006760:Hospitalization; D006801:Humans; D053208:Kaplan-Meier Estimate; D018579:Patient Selection; D016032:Randomized Controlled Trials as Topic / Q000379:methods*; D020127:Recovery of Function; D012107:Research Design; D018570:Risk Assessment; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome