Weight loss surgery lowers patients' risks for heart disease, according to a new review of the medical literature.

Based on three studies, the 10-year risk of suffering a heart attack dropped from more than six percent before the procedure—also known as bariatric surgery—to less than four afterwards.

"The bariatric community has recognized the remarkable metabolic benefits of weight loss surgery for several years, so we were not too surprised by the findings reported in this study," said lead researcher Dr. Helen M. Heneghan in an email to Reuters Health.

"However, these findings may surprise cardiologists and physicians who treat obese patients for weight-related illnesses on a daily basis, yet are less familiar with the dramatic metabolic effects of bariatric surgery."

Heneghan, from Ohio's Cleveland Clinic, and colleagues reviewed 52 studies involving 16,867 patients who had weight loss surgery.

After the procedures, patients shed about half their excess weight on average, according to the new report, which appears in the American Journal of Cardiology.

In 68 percent of the cases, patients saw their high blood pressure either disappear or dip, and diabetes improved in three-quarters of them as early as three months after the surgery, lasting at least up to 13 years of follow-up.

In the only study that reported on deaths from heart attacks, surgery appeared to cut the rate by half—from 1.2 percent to 0.65 percent.

"We hope that after reading this review, physicians will recognize that their obese patients with cardiovascular risk factors or established cardiovascular disease would benefit immensely from weight loss surgery," Heneghan said.

Two of the five authors of this study reported financial associations with companies that manufacture equipment used in bariatric surgery.