Defibrillators may improve survival in non-ischemic cardiomyopathy

November 11, 2003

Research from Northwestern University suggests that implantable cardioverter defibrillators (ICDs) can improve the survival rate of people who have a weakened heart muscle caused by factors unrelated to coronary artery disease - a condition known as non-ischemic cardiomyopathy. Previous studies showed that people whose heart muscle had been weakened as a result of coronary artery disease (ischemic cardiomyopathy) could benefit from ICDs. This research is among the first to indicate that the approximately 200,000 other Americans who suffer from this condition may also benefit.

An ICD is a small device implanted under the skin near the collarbone and connected to the heart with insulated wires called leads. ICDs deliver shocks and other electrical therapies to the ventricles to stop ventricular tachyarrhythmias (abnormally fast heart rhythms originating in the heart's lower chambers).

Initial results from the DEFINITE (Defibrillators in Non-Ischemic Cardiomyopathy Treatment Evaluation) ICD were presented today at the American Heart Association's Scientific Sessions 2003 conference in Orlando, Florida by principal investigator Alan Kadish, M.D., Chester D. and Deborah M. Cooley Professor of Medicine from Feinberg School of Medicine at Northwestern University in Chicago.

The DEFINITE study, initiated in May 1998, followed 458 participants at 48 medical centers in the United States and Israel. Participants were randomized into two groups -- one receiving standard heart failure drug therapy (control group) and the other receiving drug therapy plus an implant of a St. Jude Medical ICD. The goal was to evaluate whether the ICDs offered an overall survival benefit to those who received them.

During the study, overall mortality at two years was 13.8 percent in the standard therapy (control) group versus 8.1 percentin the ICD group. Though these results did not reach the level of statistical significance defined in the study protocol, they do show a strong trend toward reduction of overall mortality. The research did show a statistically significant reduction in the rate of arrhythmic death. Of the 56 total deaths, 11 people in the control group, while only three people in the ICD group, died from cardiac arrest.

"The DEFINITE study showed that ICDs can reduce the risk of sudden cardiac death in non-ischemic cardiomyopathy patients and tend to reduce all-cause mortality," Kadish said. "This finding was especially dramatic in Class III heart failure subjects, consistent with previous studies on preventive use of ICDs in this category of patients."

In cardiomyopathy, a patient's heart is typically enlarged and gradually weakens over time, leaving the patient at risk for life-threatening ventricular tachyarrhythmias (abnormally fast heart rhythms originating in the heart's lower chambers). These tachyarrhythmias include ventricular tachycardia (VT) and ventricular fibrillation (VF) -- common contributors to sudden cardiac arrest and the number one cause of cardiac death in the United States. Sudden cardiac arrest accounts for approximately 300,000 deaths annually.
-end-


Northwestern University

Related Cardiac Arrest Articles from Brightsurf:

Outcomes for out-of-hospital cardiac arrest during COVID-19 pandemic
This study used a large US registry of out-of-hospital cardiac arrests to asses the association between the COVID-19 pandemic and the outcomes of out-of-hospital cardiac arrests, including in areas with low and moderate COVID-19 disease.

Cardiac arrest is common in critically ill patients with COVID-19
Cardiac arrest is common in critically ill patients with covid-19 and is associated with poor survival, particularly among patients aged 80 or older, finds a study published by The BMJ today.

In-hospital cardiac arrest in COVID-19
Outcomes of in-hospital cardiac arrest among patients with COVID-19 are examined in this case series.

New risk tool developed for cardiac arrest patients
Experts have developed a risk score to predict cardiac arrest patient outcomes.

Intravenous sodium nitrite ineffective for out-of-hospital cardiac arrest
Among patients who had an out-of-hospital cardiac arrest, intravenous sodium nitrite given by paramedics during resuscitation did not significantly improve their chances of being admitted to or discharged from the hospital alive, according to research presented at the American College of Cardiology's Annual Scientific Session Together with World Congress of Cardiology (ACC.20/WCC).

Getting to the heart of epinephrine use in pediatric cardiac arrest patients
The effectiveness of epinephrine treatment during resuscitation of adult patients with cardiac arrest is generally promising, but little is known about its effects in pediatric patients.

Bystanders can help more cardiac arrest victims survive
Only 8% of Americans survive cardiac arrest outside a hospital, but that percentage could increase significantly if bystanders recognize cardiac arrest and perform simple lifesaving tasks, a UVA Health physician says in a New England Journal of Medicine article.

Opioid-related cardiac arrest patients differ from other cardiac arrests
People who suffer cardiac arrest due to an opioid overdose are younger, have fewer chronic medical conditions and may be more likely to be to receive bystander CPR, according to a review of emergency response records in Maine.

Selective coronary angiography following cardiac arrest
In the current issue of Cardiovascular Innovations and Applications volume 4, issue 2, pp.

Sudden cardiac arrest in athletes: Prevention and management
It's marathon season, and every so often a news report will focus on an athlete who has collapsed from sudden cardiac arrest.

Read More: Cardiac Arrest News and Cardiac Arrest Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.