Statins Help Those With Heart Valve Problems

But it apparently has nothing to do with lower cholesterol

TUESDAY, Nov. 19, 2002 (HealthDayNews) -- The cholesterol-lowering drugs known as statins may slow the narrowing of arteries in the heart, but new research suggests their effect has nothing to do with their ability to lower cholesterol.

"We observed that progression of aortic stenosis [AS] is half the speed in patients on statins," says senior author Dr. Maurice E. Sarano, director of the valvular heart clinic at the Mayo Clinic. However, "we noted no association between total cholesterol and AS progression."

Aortic stenosis is a narrowing of the aortic valve opening that often occurs in people older than 60. This causes the left ventricle to pump harder to push the blood forward. Eventually not enough blood gets to the heart, and heart failure may result. Since plaque is thought to narrow the heart's arteries, those with AS are often treated with statins to reduce their cholesterol.

While neither total cholesterol nor low-density lipoprotein, or "bad," cholesterol was found to be significantly associated with AS progression, being on statins was found to be beneficial to patients, Sarano reports.

The study, published in tomorrow's issue of the Journal of the American College of Cardiology, included 156 patients with AS, 38 of whom were on statins. Those on statins had a notably slower rate of progression of the disease, Sarano says. This was true despite the fact that most were on a relatively low dose of statins.

Researchers followed the patients for an average of 3.7 years. In that time, those not taking statins had their aortic valve area reduced by about 7 percent per year. Those on statins had the same area shrink by only about 3 percent annually.

Many of the untreated patients progressed from moderate stenosis to severe stenosis. As a result, some of the untreated patients became candidates for valve-replacement surgery while those on statins avoided the need for surgery.

Sarano says he cannot be sure that cholesterol does not play a role in AS, or that statins do not effectively lower cholesterol. "We cannot discard the effect of cholesterol" as the cholesterol may be exerting its effect in the tissue rather than the blood, Sarano says. However, the real effect of the statins may be that they decrease inflammation in the aorta, or "they slow calcium metabolism, which may also prevent the progression of aortic stenosis," he says. "Statins probably have a combination of effects."

Patients with severe AS may eventually require surgery. However, those needing surgery are usually elderly and not the best candidates for the operation, Sarano says. If there is a way to drastically slow the progression of the disease, as this study indicates statins may do, it is possible that some patients may never require surgery at all, he adds.

Dr. Stephen Smith, inpatient director of cardiology at Henry Ford Hospital in Detroit, says many drugs that come on the market do not end up being widely used for their first indication. He points out that Viagra was originally touted as an anti-anginal drug, and statins may prove to be most beneficial for reasons other than lowering cholesterol.

Although he would like to see the results of more studies before switching patients to statins, this study is very exciting, Smith says: "The best thing would be if we could forestall the operations."

Dr. Rodman Starke, former executive vice president of the American Heart Association, thinks this study "is quite convincing" as is. There are not many serious side effects associated with the use of statins, although a small number of patients have liver abnormalities that return to normal when the medication is stopped, he says. Patients who clearly have AS may benefit from statins, he says: "It would do more good than harm."

Sarano says they are hoping for funds from the National Institutes of Health to start clinical studies. "We should conduct clinical trials that prove the medications work."

What To Do

Learn more about aortic stenosis from the National Institutes of Health or the American Heart Association.

SOURCES: Maurice E. Sarano, M.D., director, Valvular Heart Disease Clinic, Mayo Clinic, Rochester, Minn.; Stephen Smith, M.D., inpatient director, cardiology, Henry Ford Hospital, Detroit; Rodman Starke, M.D., former executive vice president, science and medicine, American Heart Association; Nov. 20, 2002, Journal of the American College of Cardiology
Consumer News