SAN FRANCISCO—Adding cardiac resynchronization therapy (CRT) to implantable cardioverter defibrillator (ICD) therapy reduces mortality in mild to moderate heart failure (HF) patients, according to the results of the RAFT trial presented May 6 at the 32nd annual meeting of the Heart Rhythm Society.
Previous research has shown that the addition of CRT to ICD can prevent HF hospitalization and reduce mortality in HF patients and those with a wide QRS. Researchers during the RAFT trial analyzed the effects of CRT on various modes of death (arrhythmia, HF, MI, cardiac procedure or stroke, among others).
Mario Talajic, MD, cardiac electrophysiologist at the Montreal Heart Institute, and colleagues enrolled 1,768 NYHA Class II or III congestive HF patients who had an ejection fraction less than or equal to 30 percent and a QRS of greater or equal to 120 ms. The patients were randomized to receive either an ICD (904 patients) or both CRT and ICD treatment (894 patients).
Patients had an average age of 60 years, 80 percent were male and 12 percent had a history of atrial fibrillation (AF).
The researchers reported events, both cardiovascular or non-cardiovascular, during the RAFT (Results from the Resynchronization-defibrillation for Ambulatory heart Failure Trial).
Talajic reported that 422 deaths occurred—236 in the ICD group and 186 in the CRT-ICD group—during the duration of the study. Seventy-one percent of deaths were caused by a cardiovascular event, 166 in the ICD arm and 132 deaths in the CRT-ICD arm.
The rates of non-cardiovascular deaths was 29.7 percent in the ICD-alone arm and 29 percent in the CRT-ICD arm.
“The addition of the CRT to the ICD was shown to reduce the composite of death or CHF hospitalization," Talajic noted. However, the researchers also found that there was increased mortality in the ICD arm after one-year.
During the subanalysis, the investigators found that 49 patients in the ICD-alone arm experienced death caused by arrhythmia, 95 experienced deaths associated with HF and 13 patients died of stroke. These numbers in patients who received both CRT and ICD therapy were 43, 81 and 4, respectively.
“The addition of CRT to ICD reduces mortality by 25 percent,” Talajic concluded. “These effects are predominantly mediated by reductions in cardiovascular mortality, which was driven by the reductions of HF, arrhythmic death and stroke.”