Implanted heart defibrillators may help elderly heart failure patients live longer, a study released today suggests.

Heart failure is a chronic condition in which the heart muscle is weakened and cannot pump blood efficiently enough to meet all the body's needs -- leading to symptoms like fatigue and breathlessness on exertion.

People older than age 65 account for more than 70 percent of heart failure cases, yet they are underrepresented in trials of implantable cardioverter defibrillators, or ICDs, and so the effectiveness of ICDS has not been clearly established for this group.

Dr. Gregg C. Fonarow, from UCLA Medical Center, Los Angeles, and his co-authors addressed this question by analyzing data from 4,685 elderly men and women with heart failure who participated in a heart failure treatment trial.

A total of 376 patients (8.0 percent) received ICDs during a hospital stay.

At all time points during the 3-year follow-up period, death rates were significantly lower in patients with ICDs than in those without ICDs (20 percent versus 28 percent at 1 year, 31 percent versus 42 percent at 2 years, and 38 percent versus 52 percent at 3 years).

All told, the investigators calculate that ICD use reduced the risk of death at 3 years by 29 percent.

Our findings, which reflect the experiences of a mix of patients with...heart failure in the community, suggest that ICDs are clinically effective in older patients with heart failure up to age 84 years, the researchers conclude.

SOURCE: Circulation: Heart Failure, online December 15, 2009.