2011 ACC: CABG Carries the Lead over Medical Therapy for Heart Failure

Studies comparing CABG and medical therapy in patients with heart failure show that viable myocardium has no effect on mortality.

NEW ORLEANS — April 4, 2011 – Bypass surgery surpassed a medical therapy regimen in patients with heart failure, researchers reported here today in a late-breaking news conference at the American College of Cardiology’s (ACC) 60th Annual Scientific Session and ACC.i2 Summit.

Eric J. Velazquez, MD, associate professor of medicine and director of the cardiac and diagnostic unit and echocardiogic laboratories at Duke University Medical Center, Durham, NC, presented “Medical Therapy with or without Coronary Artery Bypass Graft Surgery in Patients with Ischemic Cardiomyopathy: Results of the Surgical Treatment of Ischemic Heart Failure.”

The take-home message is that patients with viable hearts did better with CABG than medical therapy, with a reduced risk of cardiovascular death (19%) and combined risk of any cause plus hospitalization by 26% (p=0.005). “Although there is a wealth of information that supports CABG, there is an early hazard, and the fairest approach is to evaluate each patient’s prognosis. If they have a low likelihood of living two years, you don’t want to take the risk of having surgery, and medical therapy may not be the better option,” said Velazquez.

When data was analyzed on the groups that included crossovers, the reduced risk was 25% (p=0.005), and when data was analyzed according to the treatment, the patients’ risk from any cause was 30 to 50%. “STICH is the largest randomized controlled study ever to compare CABG plus the best possible medical therapy to aggressive medical therapy alone in patients with coronary artery disease and heart failure,” according to Valazquez. The disease affects about six million people and about third have blockages their coronaries.

The study randomized 602 patients to ideal medical therapy and 610 to CABG plus ideal medical therapy. The study included patients from 99 medical centers in 22 countries and followed them for about five years. Bypass surgery reduced the risk of death from any cause by 14% when compared to medical therapy, but the finding was not statistically significant.

Robert Bonow, MD, professor of medicine and director of the Center for Cardiovascular Innovation at Northwestern Feinberg School of Medicine, Chicago, presented “Influence of Myocardial Viability on Outcome of Patients with Coronary Artery Disease and Left Ventricular Dysfunction Undergoing Medical Therapy with and without Surgical Revascularization: Results of the Surgical Treatment for Ischemic Heart Failure Trial.”

For the study, researchers conducted a substudy using a cohort from the Surgical Treatment for Ischemic Heart Failure (STICH) trial to determine whether nuclear perfusion scan or dobutamine echocardiology could provide clues to myocardial viability, which is basically heart tissue that can be salvaged if provided with adequate blood supply. According to Bonow, in this five-year study of 601 patients, imaging “did provide valuable information and the likelihood of long term survival.” Bonow also said that “Patients with living heart tissue were 40 % less likely to die during follow up when compared with patients with irreversible heart damage,” but cautioned that “this was not helpful in identifying which patients will benefit from surgery.”

The STICH and STICH Viability substudies were funded by the NHLBI. No conflict was reported by the authors.