Rationale and design of a randomized controlled trial to assess the safety and efficacy of cardiac resynchronization therapy in patients with asymptomatic left ventricular dysfunction with previous symptoms or mild heart failure - the REsynchronization reVErses Remodeling in Systolic left vEntricular dysfunction (REVERSE) study

Background Cardiac resynchronization therapy (CRT) improves symptoms, reduces heart failure (HF)-related hospitalizations, and reverses left ventricular remodeling in some patients with moderate to severe HF and ventricular dyssynchrony defined by a prolonged QRS duration. The effects of CRT on HF outcomes in patients with asymptomatic left ventricular dysfunction (ALVD) or mild HF remain to be determined. Methods The REsynchronization reVErses Remodeling in Systolic left vEntricular dysfunction (REVERSE) study is a prospective, multicenter, randomized, double-blind, parallel, controlled clinical trial designed to establish whether CRT combined with optimal medical treatment can attenuate HF disease progression compared with optimal medical treatment alone in patients with ALVD New York Heart Association class I American College of Cardiology/American Heart. Association stage C or New York Heart Association class II HF, QRS duration >= 120 milliseconds, left ventricular ejection fraction <= 0.40, and left ventricular end-diastolic diameter >= 55 mm. The primary end point is the HF clinical composite response and left ventricular end-systolic volume index is the first-order secondary end point. Approximately 500 patients from 100 centers in the United States, Canada, and Europe will be randomized to CRT versus no CRT. The follow-up is 5 years in total with the primary and first secondary end points reported at 12 months. Enrollment began in September 2004 and is expected to be completed in 2006. Conclusion REVERSE will assess the safety and efficacy of CRT in patients with ALVD or mild HF and electrocardiographic evidence of ventricular dyssynchrony.