NEW YORK (Reuters Health) – Cardiac resynchronization therapy added to optimal medical therapy or in addition to an implantable cardioverter defibrillator (ICD) reduces mortality significantly in mild to moderate congestive heart failure, Canadian investigators report.

Their conclusion is based on results of a meta-analysis. Writing in the Canadian Medical Association Journal online January 31, Dr. George Wells, at the University of Ottawa Heart Institute, and colleagues point out that a mortality benefit of adding cardiac resynchronization to an ICD had not been demonstrated until the recent “Resynchronization/Defibrillation for Ambulatory Heart Failure Trial” (RAFT).

“We performed a meta-analysis including the RAFT trial to determine the effect of cardiac resynchronization therapy with or without an implantable defibrillator on mortality,” the authors explain. The meta-analysis included 12 relevant studies.

The researchers found that, in general, the relative mortality risk was reduced by 22% when cardiac resynchronization was added to prior therapy.

Specifically, cardiac resynchronization therapy plus optimal medical therapy significantly reduced mortality compared with optimal medical therapy alone (relative risk [RR] 0.73), according to the report.

Similarly, compared to an ICD alone, the addition of cardiac resynchronization again reduced mortality (RR 0.83). On further analysis, this benefit was seen to be confined to patients with NYHA class I or II heart failure.

“Our findings indicate an unequivocal benefit of cardiac resynchronization therapy in addition to optimal medical therapy or an implantable cardioverter defibrillator in reducing all-cause mortality,” Dr. Wells and colleagues conclude.

They add, “Cardiac resynchronization therapy may now be extended to a much wider proportion of patients with heart failure, improving long-term outcomes in this growing population.”

Reference:

Cardiac resynchronization therapy: a meta-analysis of randomized controlled trials


CMAJ 2011;