Patients who received two pace-making devices -- one to correct how the heart pumps and another to keep its beats regular -- were more likely to report gains in their overall quality of life after six months than those who got only the rhythm aid. They also were able to exercise better and had a general improvement in their daily activities.
The study, reported in the May 28 Journal of the American Medical Association, was not able to determine if the therapy prolonged life or significantly eased heart failure.
"The combination of [the two pacemakers] does, in fact, yield very nice outcomes," says Dr. Clyde Yancy, a spokesman for the American Heart Association (AHA) who is familiar with the findings.
Quality-of-life issues and the ability to exercise are increasing concerns of people with heart failure, adds Yancy, a cardiologist at the University of Texas Southwestern Medical Center.
Heart failure affects as many as five million Americans, directly and indirectly, accounting for 280,000 deaths each year, according to the AHA. The condition involves a gradual weakening of the heart muscle, depriving the rest of the body of blood. Heart failure often includes a buildup of fluid in the lungs that strains breathing.
Drugs including beta-blockers, diuretics and ACE inhibitors can help ease the symptoms of the ailment, but it has no cure.
About 10 percent of people with heart failure have an electrical anomaly in their ventricles, or pumping chambers, that is a major cause of death. Cardiac resynchronization therapy, or CRT, is intended to reduce that risk by making the muscles contract more efficiently.
Implantable defibrillators (ICDs) even out abnormal heart rhythms that are linked to sudden death. Roughly 5 percent of heart-failure patients in the United States, or about 250,000 people, are good candidates for treatment with both devices.
The study followed 369 men and women with moderate-to-severe heart failure that failed to respond well to medication. Of those, 187 had both CRT and an implantable defibrillator that were functioning, while the rest had a working defibrillator but the CRT hadn't been activated.
After six months, more patients with both pacemakers reported improvements in their quality of life than those with defibrillators alone. They were also more likely to show gains in certain measures of exercise capacity, though unlike in previous studies CRT didn't help people on a test of timed walking.
Not everyone benefited from the combined pacemakers. While 52 percent of people who received the devices showed clinical improvement, one-third worsened. Adding a CRT also raises the risk of complications, which occurred in almost half of those who got both devices.
Still, the study suggests that the dual approach does help patients feel better and doesn't interfere with the action of the defibrillator, the researchers say.
"Patients who get the combined treatment get some of the important benefits of cardiac resynchronization, and at the same time the defibrillator function of the combined devices seems to work well," says Dr. David Bradley, a cardiology fellow at the Johns Hopkins University School of Medicine and author of an editorial accompanying the journal article.
Although the latest study wasn't designed to detect a reduction in death rates with the combination treatment, Bradley says previous studies hint that one exists, at least in the short-term.
"There are some encouraging findings from uncontrolled trials, and patients seem to tolerate this therapy for more than two years. But what we want to see is a long-term randomized trial," he adds.
One such study is now under way.
Implanting a CRT can be tricky, with doctors failing to place the pacing leads in 12 percent of patients, the study found. The devices, which are about the size of a silver dollar, can cost as much a $50,000.
The study was funded by Medtronic Inc., which sells pacemakers.