Patients who survived sudden cardiac arrest or had a near-fatal fast
heart rhythm, called an arrhythmia, are sometimes treated with an implantable
to prevent future cardiac arrest.
An ICD is placed under the skin and
connected to the heart with wires, which detects when the heartbeat is
irregular and can return the heart rhythm to normal with an electrical
shock - also known as defibrillation.
‘Of patients over age 65 who received an implantable cardioverter-defibrillator after surviving sudden cardiac arrest or a near-fatal arrhythmia, almost 80% survived two years - a higher rate than found in past trials.’
Of patients over age 65 who received an ICD after surviving sudden cardiac arrest
or a near-fatal arrhythmia, almost 80% survived two years - a
higher rate than found in past trials performed to demonstrate the
efficacy of the devices in this situation, according to a study today in
the Journal of the American College of Cardiology
"In this population, there is a very high risk for these cardiac
events to happen again," said the study's lead author, Frederick
Masoudi, professor of medicine at the University of Colorado
Anschutz Medical Campus and the Chief Science Officer of the American
College of Cardiology's National Cardiovascular Data Registry. "I was
surprised to see the survival rates in our study were as high as they
Masoudi said the findings suggest that physicians are doing a good
job of selecting elderly patients for the implantable defibrillators.
Past randomized clinical trials of ICDs were relatively small, were
conducted several decades ago and did not include many older patients.
ICD technology and treatment for underlying heart disease have since
improved, Masoudi said. In an analysis of these clinical trials, the
risk of death for patients at least 75 years of age was approximately 35% among those receiving an ICD, compared with 22% in the
current study, in which 75% of the population was at least 75
"It's important to study older patients, because they often have
other co-existing medical conditions, which may have an impact on their
outcomes," Masoudi said.
Using data from NCDR's ICD Registry, the study included 12,420
Medicare beneficiaries undergoing an ICD implantation after surviving
sudden cardiac arrest or a near-fatal ventricular arrhythmia, between
2006 and 2009 in almost 1,000 U.S. hospitals.
The researchers found 65.4% of patients were hospitalized
during the two years after receiving an ICD, ranging from 60.5%
in those less than age 70 to 71.5% in those 80 and older. In
addition, 13.1% among those less than 70 years old and 21.9% of those 80 and older were admitted to a skilled nursing
facility. The risk of admission to a skilled nursing facility was
greatest in the first 30 days after the procedure. The risks of
hospitalization and admission to skilled nursing facility were all
greater with increasing patient age.
The researchers noted that the high hospitalization and skilled
nursing facility admission rates, particularly among the oldest
patients, indicate there are substantial care needs after an ICD is
"This gives us a good picture of the health care needs of this population after their procedure," Masoudi said.
Limitations include that the study was not designed to evaluate the
effectiveness of ICDs and did not compare the patients receiving the
devices with a control group who did not receive them.
In an editorial accompanying the study, Sumeet S. Chugh, associate director of the Cedars-Sinai Heart Institute, wrote that the
findings from the new study would suggest that although patients over
age 75 implanted with ICDs after a sudden cardiac arrest or near-fatal
ventricular arrhythmia "may have reasonable overall survival, they also
have significantly high rates of admission to hospitals and skilled
nursing facilities, with no clear evidence of mortality benefit from the
He said that until more research is done about the devices in
elderly patients, doctors should consider non-heart-related co-occurring
medical conditions and frailty along with age in their decision-making
process about ICDs. They should provide the patient with a clear
understanding of the rationale and limitations of the ICD, encourage
advance directives and bring up the possibility of deactivating the ICD
if the patient is nearing end of life.