The findings are important because coronary artery disease patients can see a significant benefit with a successful procedure. The resulting weight loss is also followed by an improvement in blood pressure, cholesterol, blood sugar and sleep apnea, all factors linked to coronary artery disease.

"In essence, obese patients with coronary artery disease might be those who need this surgery the most, but get it the least," says Francisco Lopez-Jimenez, M.D., Mayo Clinic cardiologist and lead author of the study.

The study is the first report about the safety and efficacy of bariatric surgery in patients with a history of coronary artery disease, the authors say.

"Roux-en-Y bariatric surgery appears to be an important alternative in treating patients with coronary artery disease and obesity who cannot lose weight with standard approaches," says Dr. Lopez-Jimenez. "The surgery appears to be safe in properly evaluated patients with cardiovascular disease."

But Dr. Lopez-Jimenez says additional research is needed to determine the effect of bariatric surgery on cardiovascular events among these patients. The analysis by the Mayo researchers included 52 patients who were identified with coronary artery disease, who underwent bariatric surgery at Mayo Clinic Rochester between March 1995 and January 2002. The effects on body weight and other cardiovascular risk factors were analyzed after surgery. After an average follow-up of 2.5 years with patients, the researchers found significant decreases in weight loss, body mass index and blood pressure. Blood analysis showed decreases in key indicators, as well.

MayoClinic notes that coronary artery disease is the most common type of heart disease, affecting about 13 million Americans. The cause of coronary artery disease is atherosclerosis -- the gradual buildup of plaque in the arteries that feed the heart. Each year, more than 500,000 Americans die of complications of coronary artery disease.

The failure of conventional techniques to treat severe obesity successfully sparked interest in surgical strategies. In 1991, the National Institutes of Health Consensus Conference officially acknowledged the efficacy of bariatric surgery in producing short-term and long-term weight loss.

The use of these procedures has gained acceptance and is now considered an option that physicians discuss with their obese patients when other weight loss options have failed.

However, Dr. Lopez-Jimenez said diet and increased physical activity should remain as the initial approach in the treatment of obesity in patients with coronary artery disease. Bariatric surgery should not be considered first for treatment of obese patients with coronary artery disease because of its high cost and the potential risk of long-term complications in the digestive system.

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