Hidden Benefits of ACE Inhibitors.

Over the last 10 years or so, angiotensin converting enzyme (ACE) inhibitors have become widely prescribed for high blood pressure and are standard care for people with heart failure. There are now many members of this drug family, which includes agents such as captopril (Capoten), enalapril (Vasotec), and lisinopril (Zestril, Prinivil). By helping blood vessels relax and dilate, these drugs lower blood pressure and ease the heart's workload.

The long-term effects can be life saving. The first major study to demonstrate the potential of ACE inhibitors was performed by investigators from Harvard Medical School, including Harvard Heart Letter editorial board member Eugene Braunwald, M.D. This research showed that patients whose hearts had been substantially damaged by a heart attack lived longer if they were treated with the drug captopril instead of a placebo. Other studies with ACE inhibitors have shown similar findings for people whose heart failure is due to damaged left ventricles.

But one of the consistent and intriguing findings from the studies has been that these drugs appear to save even more lives than one would expect solely from lowered blood pressure and a lightened workload for the heart. Some researchers speculate that ACE inhibitors might keep blood vessels healthy in other ways. Huge international trials are underway to explore whether this class of drugs might offer life-saving benefits to people who do not have heart failure and whose left ventricles are working just fine.

If these trials confirm this suspicion, then ACE inhibitors might help prevent heart attacks in a much broader population of people at increased risk. Recently, one of those trials was stopped early because the committee monitoring the results determined that the study's outcome was clear sooner than expected. Sometimes, trials are stopped because the drug being tested is found to be harmful. In this case, the study was stopped because the patients receiving ACE inhibitors were doing so much better that it would have been unethical to withhold the drug from study patients assigned to receive the placebo.

HOPE

Early findings from the Heart Outcomes and Prevention Evaluation (HOPE) trial were presented in August 1999 at the European Society of Cardiology meeting in Barcelona, Spain. In this trial, investigators randomly assigned 9,541 people in 19 different countries to take ramipril or a placebo each day. During the second phase of the research, they assigned an additional 9,540 people to take 400 IU of vitamin E or a placebo daily.

All the study volunteers were at least 55 years old and had some evidence of diseased blood vessels that suggested a high risk of heart attack. More than 80% had known coronary artery disease, and 53% had already had a heart attack. Eleven percent of the participants had had strokes or near-strokes. In addition, 38% had diabetes, 46.5% had high blood pressure, and 66% had high cholesterol levels. ...