Implants Protect People With Heart Failure
Advanced Pacemakers, ICDs Reduce Risk of Death for Those With Heart Failure
May 19, 2004 -- For most people with severe heart failure and
irregular heartbeats, a combination of a high-tech pacemaker and implantable
defibrillator may provide the best protection against death, according to new
Researchers say the results of the two major studies published
in this week's New England Journal of Medicine may lead to wider use of
the devices in people with severe heart failure -- a condition in which the
heart cannot pump enough blood to meet the body's needs.
The pacemakers studied not only help the heart keep up when its
natural beat is too slow like traditional pacemakers, but they also make the
heart pump more efficiently. Meanwhile, an implantable cardioverter
defibrillator (ICD) delivers an electrical shock to prevent potentially
dangerous heart rhythm abnormalities.
In the first study, researchers compared the effectiveness of
the advanced pacemaker and implantable defibrillator vs. drug therapy in
preventing hospitalization or death in people with advanced heart failure. They
found the devices offered the greatest benefits, and use of both reduced the
risk of death in patients with severe heart failure by 36%.
The second study showed that implanting a defibrillator in
people with heart failure not caused by coronary artery disease or hardening of
the arteries significantly reduced their risk of sudden death. People with this
type of heart failure often die suddenly due to an irregular heartbeat.
Devices Beat Drug Therapy Along for Heart Failure
The first study looked at whether adding a pacemaker or ICD to
traditional drug therapy for heart failure provided additional health benefits
in reducing the risk of death or hospitalization for more than 1,500 people
with advanced heart failure.
The heart failure patients were randomly assigned to receive
drug therapy (including diuretics, ACE inhibitors, beta-blockers, and others),
alone or in combination with either a pacemaker or a pacemaker-defibrillator
Researchers found that compared with drug therapy alone, use of
a pacemaker reduced the risk of death or hospitalization from any cause by 19%,
and use of both devices reduced the risk by 20%.
Overall, the study showed that use of a pacemaker reduced the
risk of death from any cause by 24%, and the combination
pacemaker-defibrillator reduced the risk by 36%.
ICDs Reduce Sudden Death Risks
In the second study, researchers looked at whether an
implantable defibrillator was useful as a primary prevention tool in people
with a form of heart failure known as nonischemic cardiomyopathy. This type of
heart failure is not caused by coronary artery disease or hardening of the
arteries and commonly causes sudden death due to an irregular heartbeat.
Researchers say treatment with drugs such as ACE inhibitors and
beta-blockers has been shown to prolong the lives of people with this type of
heart failure, but these people are still at risk for sudden death due to