Implantable defibrillators save lives but may increase heart failure risk

Implantable cardioverter defibrillators (ICDs) reduce the risk of sudden cardiac death but may increase the risk of subsequent heart failure in patients who live longer, according to a study published in Circulation: Journal of the American Heart Association.

“Some patients whose lives were prolonged by ICDs were sicker and more prone to develop heart failure,” said Ilan Goldenberg, M.D., research assistant professor at the University of Rochester Medical Center and lead author of the latest report from the Multicenter Automatic Defibrillator Implantation Trial-II (MADIT-II). “The ICD kept them alive by preventing sudden cardiac death as their heart disease naturally progressed to heart failure.

“Patients who developed heart failure had almost four times the increase in risk of death during follow up. This study should direct more attention to the prevention of heart failure in patients receiving an ICD.”

The MADIT-II trial included 1,232 heart attack patients with an ejection fraction of 30 percent or less who had a heart attack at least a month before enrollment. Researchers randomly assigned patients to ICD (single or dual chamber) or best medical care.

Ejection fraction is a measure of the heart's ability to efficiently pump blood to other parts of the body. An ejection fraction of 60 percent is healthy, so the MADIT-II patients were pumping blood at about half the rate of healthy people.

Compared to patients who received only medical therapy after a heart attack, those who had ICDs implanted were 39 percent more likely to have a first hospitalization for heart failure and 58 percent more likely to be hospitalized for recurrent heart failure during an average 20-month follow up.

The overall survival benefit was 42 percent for patients who received a single chamber ICD and 51 percent for those with a dual chamber. Researchers analyzed data from 1,224 study patients, including 402 who received single-chamber devices and 313 who were implanted with dual-chamber devices.

Twenty-three percent of patients who received ICDs in the MADIT-II trial were hospitalized for HF during 20 months of follow-up versus 17 percent of patients who received only medical therapy.

Patients who received single-chamber devices did not suffer a reduced survival benefit if they developed heart failure. However, patients who were implanted with dual-chamber devices had a significant reduction in survival benefit after heart failure, Goldenberg said.

Media Contact

Karen Astle EurekAlert!

More Information:

http://www.heart.org

All latest news from the category: Medical Engineering

The development of medical equipment, products and technical procedures is characterized by high research and development costs in a variety of fields related to the study of human medicine.

innovations-report provides informative and stimulating reports and articles on topics ranging from imaging processes, cell and tissue techniques, optical techniques, implants, orthopedic aids, clinical and medical office equipment, dialysis systems and x-ray/radiation monitoring devices to endoscopy, ultrasound, surgical techniques, and dental materials.

Back to home

Comments (0)

Write a comment

Newest articles

Lighting up the future

New multidisciplinary research from the University of St Andrews could lead to more efficient televisions, computer screens and lighting. Researchers at the Organic Semiconductor Centre in the School of Physics and…

Researchers crack sugarcane’s complex genetic code

Sweet success: Scientists created a highly accurate reference genome for one of the most important modern crops and found a rare example of how genes confer disease resistance in plants….

Evolution of the most powerful ocean current on Earth

The Antarctic Circumpolar Current plays an important part in global overturning circulation, the exchange of heat and CO2 between the ocean and atmosphere, and the stability of Antarctica’s ice sheets….

Partners & Sponsors