CRT Reduces Mortality for Mild-to-Moderate Heart Failure

Cardiac-resynchronization therapy (CRT) implants synchronize and strengthen a fading heartbeat, while reducing risk of death by 24% compared to current treatments.

Researchers at the University of Ottawa Heart Institute (UOHI; Canada), Goethe Universität (Frankfurt, Germany), and 22 other centers in Canada, Australia, and Europe randomly assigned 1,798 patients with New York Heart Association (NYHA) class II or III heart failure, a left ventricular ejection fraction of 30% or less, and an intrinsic QRS duration of 120 ms or more or a paced QRS duration of 200 ms or more to receive either an implantable cardioverter-defibrillator (ICD) alone or an ICD plus CRT. The patients were followed for a mean of 40 months, and the primary outcome was death from any cause or hospitalization for heart failure.

The results showed that the primary outcome occurred in 297 of 894 patients (33.2%) in the ICD-CRT group, compared to 364 of 904 patients (40.3%) in the ICD group. A breakdown of the results showed that in the ICD-CRT group 186 patients died, as compared with 236 in the ICD group, while 174 patients were hospitalized for heart failure, as compared with 236 in the ICD group. However, at 30 days after device implantation, adverse events had occurred in 124 patients in the ICD-CRT group, compared to only 58 in the ICD group. The study was published in the November 14, 2010, issue of the New England Journal of Medicine (NEJM).

"This kind of device brings the potential to save thousands of lives in Canada alone and offers new hope to so many heart patients and their families. Helping the lower chambers of the heart beat strongly and in unison can improve a person's quality of life, keep them out of hospital longer, and reduce their risk of sudden death,” said lead author Anthony Tang, M.D., of the UOHI.

CRT devices, also known as biventricular pacemakers, are a type of pacemaker that can pace both the septal and lateral walls of the left ventricle. By pacing both sides of the ventricle, the pacemaker can resynchronize a heart whose opposing walls do not contract in synchrony, which occurs in approximately in 25% to 50 % of heart failure patients.

Related Links:
University of Ottawa Heart Institute
Goethe Universität