Implants Protect People With Heart Failure
Advanced Pacemakers, ICDs Reduce Risk of Death for Those With Heart Failure
ICDs Reduce Sudden Death Risks continued...
ICDs have been used as a preventive measure to protect against
sudden death in people who have already experienced cardiac arrest or rapid and
irregular heartbeats, but researchers say that this was the first large-scale
study to look at whether defibrillators might also provide benefits in
preventing sudden death in people with this type of heart failure.
In the study, researchers randomly assigned 458 people with
this type of heart failure to receive standard drug therapy or drug therapy
plus an ICD. The participants were then followed for nearly two-and-a-half
During that time, 68 deaths occurred, but only 28 of them
occurred in the ICD group compared with 40 in the standard therapy group.
Seventeen of the deaths were sudden deaths caused by an irregular heartbeat:
three in the ICD group and 14 in the drug therapy group.
Based on those results, researchers say it's too soon to
recommend routine implantation of ICDs in all people with heart failure not
related to coronary artery disease. But the apparent benefit of the devices in
certain subgroups suggests that use of these devices should be considered on a
Valuable Information, but Proceed With Caution
In an editorial that accompanies the study, Joseph G. Rogers,
MD, and Michael E. Cain, MD, of Washington University School of Medicine, say
these studies add critical new information about the use of the new generation
of advanced pacemakers and implantable defibrillators to prevent future
They say that until now, trials evaluating this approach have
been small and evaluated the quality of life, exercise performance, and other
heart performance factors. This new data on their health benefits in reducing
illness and death is needed as doctors begin to use these relatively expensive
therapies in a larger group of patients.
In another commentary, Mark Hlatky, MD, of Stanford University
School of Medicine, says that the release of this new data will likely put
pressure on insurance providers, such as Medicare, to expand coverage for these
devices. He says it is also "very likely that the rate of implantation will
increase dramatically, propelled by the same forces that fueled the expansion
of bypass surgery."
However, as with bypass surgery, Hlatky says the key question
regarding preventive use of defibrillators is not just whether it
"works" overall, "but how much the risks, benefits, and costs vary
among the different subgroups of patients with heart disease."
The first study was supported by medical device manufacturer
Guidant, and the second was funded by a grant from St. Jude Medical, which is a