MONDAY, Feb. 7 (HealthDay News) -- A therapy to prevent heart failure is twice as effective in women as in men, a new study finds.

It's the first time that a heart treatment has been shown to offer greater benefit to women, the researchers added.

The finding was "unexpected, but extremely important," study author Dr. Arthur J. Moss, a professor of medicine at the University of Rochester Medical Center, said in a news release.

He and his colleagues looked at the effectiveness of cardiac resynchronization therapy with defibrillator (CRT-D) in 1,820 patients in Canada, Europe and the United States. CRT-D combines the benefits of both an implantable cardioverter defibrillator (ICD) and cardiac resynchronization therapy. ICDs prevent sudden, irregular rhythm-related cardiac death, and resynchronization therapy boosts heart function and reduces the risk of heart failure and related symptoms.

CRT-D is approved in the United States to treat patients with severe heart failure and those with mild heart failure to prevent them from progressing to advanced heart failure. The CRT-D device was developed by Boston Scientific, which was a partner in this study.

Among women, CRT-D led to a 70 percent reduction in heart failure and a 72 percent reduction in death. Among men, the treatment led to a 35 percent reduction in heart failure, according to the report published in the Feb. 7 issue of the Journal of the American College of Cardiology.

"It's not that men did poorly in the trial, but rather, women had really fantastic results, likely due to the type of heart disease we see more commonly in women," Moss said in the journal news release.

The women in the study were more likely to have non-ischemic heart disease, which is usually characterized by inflammatory scarring of the heart muscle. Men were more likely to have ischemic heart disease, which occurs when narrowed arteries restrict the flow of blood and oxygen to the heart.

In addition, more women had left bundle branch block, a condition that causes disorganized electrical activity throughout the heart.

The two types of heart disease that were more common among women are more likely to respond to CRT-D, the study authors explained.

More information

WomensHealth.gov has more about heart disease.