CHICAGO One in five heart defibrillators may be implanted for questionable reasons without solid evidence that the devices will help, according to a first-of-its-kind analysis.
Implanted defibrillators shock the heart back into a normal rhythm when it starts beating irregularly. They can prevent sudden death in people with advanced heart failure, but researchers havent found a benefit for other patients.
Patients whove had a recent heart attack or recent bypass surgery arent good candidates for defibrillators, for example. Guidelines dont recommend them for people newly diagnosed with heart failure, either, and those so sick that they have very limited life expectancies wont be helped.
But in the new study, which examined nearly four years of national data, 22 percent of the implant surgeries were in patients who fit one of those categories.
Some may have been appropriate, said lead author Dr. Sana Al-Khatib of Duke University School of Medicine in Durham, N.C., but its likely that many were done despite the research evidence.
Its lack of knowledge. Its ignorance. Its not keeping track of the guidelines, she said. And we may have some physicians who dont agree with the guidelines or dont think the guidelines apply to their patients.
The study, appearing in last weeks Journal of the American Medical Association, examined national registry data from nearly 112,000 patients in 2006-09.