Drug aids failing heart, cuts death rate.

Physicians who treat people suffering from heart failure may soon have a new weapon in their battle against the progressive, fatal decline in heart function. Results of a clinical study indicate that a drug called carvedilol not only increases the heart's ability to pump blood but decreases mortality by 67 percent.

"These are genuinely exciting results," says study investigator Milton Packer of Columbia Presbyterian Medical Center in New York City. "Carvedilol is associated with [overall] improvement in scores of heart function as well as decreasing mortality."

Heart failure, the only cardiac disorder with a rising incidence, affects about 3.5 million people in the United States. The condition comes about when the heart, which has gradually pumped less blood to the body, cannot meet the body's demand for oxygen. As the heart fails, the sympathetic nervous system stimulates it to pump more efficiently, thus providing more oxygen. That stimulation damages the heart muscle.

Physicians routinely give patients digitalis to enhance pumping power, diuretics to eliminate fluid buildup, and drugs known as ACE-inhibitors to dilate blood vessels. In the past decade, they have also begun to prescribe beta-blockers, which block muscle stimulation by the sympathetic nervous system.

An especially effective beta-blocker, carvedilol stops sympathetic stimulation completely. But unlike other such drugs, it also dilates blood vessels and serves as an antioxidant.

Packer, Wilson S. Colucci, formerly of Harvard Medical School in Boston, and Michael R. Bristow of the University of Colorado Health Sciences Center in Denver tested carvedilol in 1,052 people with mild, moderate, or severe heart failure. All participants took either carvedilol or a placebo in addition to their standard heart medications.

As the team reported this week at the American Heart Association meeting in Anaheim, Calif., carvedilol reduced mortality among people with moderate to severe heart failure. Bristow reported that participants' exercise capacity increased with the amount of carvedilol given.

Colucci, now at Boston University Medical Center, led the studies of carvedilol in participants with mild heart failure. Those on the drug enjoyed a 50 percent reduction in the progression of disease, as well as a significant drop in mortality, compared to the group taking the placebo.

Although he finds these results provocative, Barry M. Massie of the University of California, San Francisco points out that the study monitors people for at most 2 years and that "during that time, not many people died." He argues that longer studies are needed to validate carvedilol's early promise.

Packer agrees that further study is needed to determine whether carvedilol will become the standard of care. The Food and Drug Administration recently approved carvedilol for hypertension, but the drug is not yet available.