Long-Term Outcomes of Resynchronization-Defibrillation for Heart Failure.

Area of Science:

• Cardiology
• Medical Devices

Background:

• The Resynchronization-Defibrillation for Ambulatory Heart Failure Trial (RAFT) previously indicated a 5-year mortality benefit for CRT compared to ICDs.
• The long-term survival impact of CRT in heart failure patients remained unknown.

Purpose of the Study:

• To evaluate the long-term survival outcomes of CRT defibrillators (CRT-D) versus implantable cardioverter-defibrillators (ICDs) in heart failure patients.
• To determine if the initial survival benefit of CRT-D is sustained over an extended follow-up period.

Main Methods:

• Randomized assignment of patients with NYHA class II/III heart failure, LVEF ≤30%, and QRS duration ≥120 ms (or paced ≥200 ms) to either ICD or CRT-D.
• Long-term outcomes were assessed in 1050 patients from the eight highest-enrolling sites.
• Primary outcome: all-cause mortality; Secondary outcome: composite of death, heart transplantation, or ventricular assist device implantation.

Main Results:

• Over a median follow-up of 7.7 years (survivors: 13.9 years), CRT-D was associated with a longer time until death compared to ICD (acceleration factor 0.80, P=0.002).
• Mortality occurred in 71.2% of the CRT-D group versus 76.4% of the ICD group.
• Secondary outcome events occurred in 75.4% of the CRT-D group versus 77.7% of the ICD group.

Conclusions:

• The survival benefit of CRT-D over ICD in patients with reduced ejection fraction, widened QRS, and moderate heart failure is sustained long-term.
• The findings suggest CRT-D provides a lasting survival advantage in this patient population, extending beyond initial trial observations.