An implantable device that shocks an erratically beating heart and works to keep both ventricles beating synchronously reduced hospitalizations for heart failure by 41%, according to results reported Tuesday at the European Society of Cardiology Congress in Barcelona, Spain.
The results, reported online in the New England Journal of Medicine, were significantly better than preliminary results announced in June, when the trial was halted prematurely because of its success.
"This is a real breakthrough" for patients with mild to moderate heart disease, said Dr. Leslie Saxon, a cardiologist at USC's Keck School of Medicine, one of the study sites.
"The results are very encouraging, but we need to take them with a grain of salt," said Dr. Shephal K. Doshi, director of electrophysiology and pacing at St. John's Health Center in Santa Monica. "No one receiving the devices lived longer."
Because of the high price of the devices, he said, it is increasingly important to identify which heart-failure patients are most likely to benefit from them -- something that is not known.
The cellphone-sized combination device, called a CRT-D, incorporates an automated defibrillator and a cardiac resynchronization device that shocks both ventricles of the heart at the correct time to keep them beating properly. The device has been approved by the Food and Drug Administration for patients with severe heart disease, and about 60,000 are implanted each year in such patients.
The new study is focused on patients with a milder form of heart failure that accounts for about 70% of the 5.5 million U.S. heart failure patients. More than a million such patients die every year.
Dr. Arthur J. Moss of the University of Rochester Medical Center and his colleagues studied 1,820 patients at 110 medical centers in the United States, Europe and Canada in the $38-million trial. About a third of the patients received only an implanted defibrillator, and the rest got the combination device. They were followed for an average of 2.7 years.
Overall, the risk of being hospitalized or dying from heart failure was reduced by 41% in patients with the combination device -- from 25.3% in patients with only a defibrillator to 17.2% in those with the CRT-D.
Women's risk dropped even more, about 63%. The risk of dying from heart failure was the same in both groups, about 3% per year.
Adverse events were about the same in both groups. The primary drawback of the CRT-D is its price, at least $30,000 -- compared with about $20,000 for an implantable defibrillator. It costs about $10,000 to $15,000 for the hospitalization and surgery to implant the CRT-D.
In an editorial accompanying the report in the New England Journal of Medicine, Dr. Mariell Jessup of the University of Pennsylvania noted that it would require 12 implants of the device to prevent one hospitalization for heart failure, and asked: "Is this money that could be spent more wisely?"
Saxon, however, noted that hospitalization for heart failure was itself expensive, and that 40% of those hospitalized were rehospitalized. The incremental cost compared with a defibrillator can be easily justified, she argued.
The study was funded by Boston Scientific, which manufactures the CRT-D. Moss has received payments from the company in the past for presenting lectures.