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 haven't found a benefit for other patients.
Patients who've had a recent heart attack or recent bypass surgery aren't good candidates for defibrillators, for example. Guidelines don't recommend them for people newly diagnosed with heart failure either, and those so sick that they have very limited life expectancies won't be helped.
But in the study, which examined nearly four years of national data, 22 percent of implant surgeries were in patients in one of those categories.
Some may have been appropriate, said lead author Dr. Sana Al-Khatib of Duke Uni-versity School of Medicine in Durham, N.C., but 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 said.
The study, appearing in today's Journal of the American Medical Association, examined national registry data from nearly 112,000 patients in 2006-09.
The surgeries cost thousands of dollars, raising questions about wasted resources, Al-Khatib said. "It's all about improving the quality of care," she said.