The risk of sudden cardiac death faced by people with heart failure is offset more with an implantable defibrillator than with drug treatment, according to a new study.

Sudden cardiac death can occur when the heart stops beating suddenly or goes into a very erratic rhythm, something that can easily happen when the heart is weakened.

An implantable cardioverter-defibrillator (ICD), somewhat similar to a pacemaker, detects such events and delivers a shock to correct the problem quickly.

Conversely, antiarrhythmic drugs such as amiodarone aim to prevent the irregular rhythm developing in the first place.

In the Sudden Cardiac Death in Heart Failure Trial, Dr. Gust H. Bardy, from the Seattle Institute for Cardiac Research, and colleagues assessed the outcomes of some 2500 patients with advanced heart failure. They were randomly assigned to receive conventional therapy plus amiodarone or a placebo drug, or to be fitted with an ICD.

During an average follow-up of nearly four years, the rates of death in the amiodarone and placebo groups hovered around 29 percent, while the rate in the ICD group was significantly lower, at 22 percent.

That is to say, an ICD reduced the risk of death by 23 percent, the investigators report in this week’s New England Journal of Medicine.

The results show that “ICD therapy improves survival beyond the improvement afforded by state-of-the-art drug therapy,” Bardy and colleagues conclude.

Since they used a relatively simple and inexpensive device, they add, “Our approach to ICD therapy is widely applicable and should have a positive public health effect on the population of patients with congestive heart failure.”

SOURCE: New England Journal of Medicine, January 20, 2005.