Benefits of CRT with and without defibrillator in HF patients found

22 January 2007

COMPANION results indicate that cardiac resynchronization therapy (CRT), both alone and in combination with an implantable cardioverter defibrillator (ICD), provides important benefits in New York Heart Association (NYHA) class IV heart failure (HF) patients.

The findings show significantly increased time to all-cause mortality and reduced hospitalization rates, and a trend towards reduced mortality. The investigators say that these devices should now be considered in similar ambulatory NYHA class IV HF patients.

Researchers led by JoAnn Lindenfeld (University of Colorado, Denver, USA) examined the outcomes of patients enrolled in the COMPANION (Comparison of Medical Therapy, Pacing, and Defibrillation in HF) trial, in which 1520 patients with NYHA class III and IV HF were randomly assigned to receive optimal medical therapy (OPT), OPT plus CRT, or OPT plus CRT and ICD (CRT-D).

It is possible that class IV patients may not benefit from CRT or CRT-D because the implant procedure can destabilize the HF and worsen short-term outcomes before benefits have the time to develop, the team explains.

Among class IV patients (n=217), CRT and CRT-D both significantly improved the primary endpoint of time to death or hospitalization for any cause, with respective hazard ratios (HRs) of 0.64 (p=0.02) and 0.62 (p=0.01) relative to OPT alone.

Time to all-cause death and HF hospitalization was also significantly improved with CRT (HR=0.57, p=0.01) and CRT-D (HR=0.49, p=0.001).

Meanwhile, there was a trend toward an improvement in time to all-cause death with both CRT (HR=0.67) and CRT-D (HR=0.63).

"Our data argue strongly that CRT devices can be employed with an excellent risk-benefit ratio in class IV HF patients who did not require a hospitalization for HF in the preceding month," the authors conclude in the journal Circulation.

Circulation 2007; 115: 204-212