One in Five Defibrillator Implants (ICDs) May Be Outside the Guidelines

Chicago, ILAccording to a new study out Wednesday in the Journal of the American Medical Association as many as one in five patients, or 22 percent, may have had heart implantable cardioverter-defibrillators (ICDs) implanted when they shouldn't have, in conflict with the national guidelines.

Further, those patients who had the implants off-guideline had a significantly higher risk of in-hospital death and other adverse events.

ICDs can be implanted in patients with advanced heart failure to shock the heart back into a normal rhythm if it gets off track and beats irregularly. However, to date researchers have not found a benefit in implanting these devices in other patients, those who've suffered a recent heart attack, or have recently undergone bypass surgery. Consequently, the guidelines don't recommend implanting defibrillators in those patients newly diagnosed with heart failure, or in people who have very limited life expectancy.

The new study, retrospectively looked at four years of national data on from approximately 112,000 patients between 2006-2009. Lead author of the study, Dr. Sana Al-Khatib of Duke University School of Medicine in Durham, North Carolina, and fellow researchers found that the patients who received the implants according to the national guidelines had a reduced risk of death in hospital, and were less likely to suffer complications compared with people whose surgeries clearly fell outside the guidelines. The researchers found that 22 percent of the implant surgeries were in patients who fit one of the categories not recommended for the implant procedure.

Dr. Sana Al-Khatib said that while some of those implants may have been appropriate, it's likely that many were done despite the research evidence. "It's lack of knowledge. It's ignorance. It's not keeping track of the guidelines," she told MSNBC.com. "And we may have some physicians who don't agree with the guidelines or don't think the guidelines apply to their patients."

And, the surgeries are expensive, costing thousands of dollars, which raises the issue of wasted medical resources, Al-Khatib said.

Dr. Douglas Zipes of the Indiana University School of Medicine in Indianapolis, who helped write the research-based guidelines for the defibrillators, said the 22 percent rate is disturbingly high. He wasn't involved in the study.