Adding Cardiac Resynchronization Therapy (CRT) May Prevent Disease Progression in Asymptomatic and Mildly Symptomatic Heart Failure (HF) Patients Already on OMT

Summary

The 24-month results of the European cohort of the Resynchronization Reverses Remodeling in Systolic left ventricular dysfunction [REVERSE; NCT00271154] trial showed that CRT that is combined with optimal medical therapy (OMT) produces improved clinical outcomes, as well as improved ventricular structure and function in persons with NYHA Class I-II HF patients.

  • Interventional Techniques & Devices
  • Heart Failure Clinical Trials

The 24-month results of the European cohort of the Resynchronization Reverses Remodeling in Systolic left ventricular dysfunction (REVERSE; NCT00271154) trial showed that CRT that is combined with optimal medical therapy (OMT) produces improved clinical outcomes, as well as improved ventricular structure and function in persons with NYHA Class I-II HF patients. JeanClaude Daubert, MD, Centre Hospitalier Universitaire, Rennes, France, suggested that CRT may prevent disease progression in these patients.

The 1-year results from REVERSE failed to show that adding CRT to OMT significantly influenced the primary endpoint, which was percentage of worsening. This subset analysis (from the European dataset) included 261 patients with HF that was associated with a QRS duration ≥120 ms, an LVEF ≤40%, and left ventricular end diastolic diameter (LVEDD) ≥55 mm who received a CRT device with or without a defibrillator. Patients in REVERSE were randomly assigned to an active CRT group (CRT on; 180 patients) or a control group (CRT off; 82 patients) for 24 months, while OMT for HF was maintained. The primary endpoint was the HF clinical composite response (including all-cause mortality, HF hospitalizations, crossover due to worsening HF, NYHA class, and the patient global assessment), which compared the proportion of improved, unchanged, or worsened patients in the CRT-off versus CRT-on groups. The prospectively powered secondary endpoint was LV end-systolic volume index (LVESVi).

After 24 months, the clinical composite response was significantly (p=0.01) worsened in more patients in the CRT-off (34%) versus the CRT-on group (p=0.0006). Significant differences were noted at 6 months and remained for the duration of the study. Worsening was attributed to death or HF hospitalization in 69% of patients in the CRT-off group. Compared with patients in the CRT-off group, CRT-on patients experienced a significant reduction in LVESVi (p<0.0001) and other measures of LV remodeling. Time to first HF hospitalization or any death was significantly delayed in CRT on compared with CRT off (HR, 0.38; 95% CI, 0.20 to 0.73; p=0.003). Minnesota living with HF score, 6-minute Hall Walk score, and NYHA class score were not significantly different between the CRT-on and CRT-off groups.

Most of the results of this study concur with the earlier 12-month North American/Canadian arm of the REVERSE study [Linde C et al. J Am Coll Cardiol 2008], except in that analysis, the HF clinical composite response endpoint was not significantly different between patients who worsened in the CRT-on (16%) group compared with those in the CRT-off (21%) group (p=0.10). When questioned about this disparity, Dr. Daubert responded, “It was probably due to differences in study length.”

View Summary