MIRACLE EF Clinical Study

Medtronic, Inc. is sponsoring the MIRACLE EF study, a prospective, randomized, controlled, double-blinded, global multi-center, Cardiac Resynchronization Therapy (CRT) in Heart Failure (HF) clinical study. The purpose of this study is to evaluate market released CRT pacemaker (CRT-P) devices in symptomatic HF patients with less severe left ventricular systolic dysfunction, specifically patients with reduced left ventricular ejection fraction (LVEF) in the range of 36% to 50%. This study will support expansion of indications for CRT worldwide. The outcome of this study is expected to support modification of existing U.S. and Japanese labeling for Medtronic's implantable CRT-P devices and to provide further evidence to support changes to cardiology practice guidelines (ACC/AHA, ESC guidelines) regarding the use of CRT in patients with mild to moderate HF. Following enrollment and the baseline assessment, eligible subjects will be implanted with a CRT-P system and randomized in a 2:1 fashion to either treatment (CRT-P ON) or control (CRT-P OFF) groups. Study subjects will be followed for a minimum of 24 months or until study closure, and will remain in their randomized groups until their 60 month visit or until the study is stopped, whichever comes first. The effectiveness of CRT-P in this population will be assessed using a composite endpoint of time to first event, with event defined as All-cause mortality or HF Event. To assess the safety of CRT-P in this population, the primary safety endpoint will measure freedom from system-related complications at 6 months post-implant.