ANN ARBOR, Mich. -- This year, Medicare will pay for tens of thousands of heart patients to have high-tech devices implanted in their chests. Called ICDs or implantable cardioverter defibrillators, the expensive devices are designed to shock damaged hearts back into rhythm and save patients from sudden cardiac death, which kills 300,000 Americans each year.
But a new study finds that while many of these patients will benefit from their ICDs, a large number won't -- and a simple heart-rhythm test can tell who's who.
In fact, the study suggests that if the test were used on the majority of ICD candidates, as many as one-third could be spared the operation to implant a device, without raising their risk of sudden death. That would mean that Medicare could be spared the additional $90,000 lifetime cost of each device compared to best medical therapy.
The study, published in the January issue of the Journal of the American College of Cardiology, is based on data from 768 patients who were candidates for ICDs at Christ Hospital and the Ohio Heart and Vascular Center in Cincinnati. All of the patients had survived heart attacks but had permanent damage to their heart muscle caused by lack of blood flow -- a condition called ischemic cardiomyopathy.
Each patient received a test called microvolt T-wave alternans or MTWA, along with a battery of other tests, during their evaluation. Half of the patients went on to receive ICDs, although the MTWA test results weren't used in the decision-making process. The patients' health and the causes of any deaths were tracked for up to three years.
After that time, the data were analyzed by researchers from the University of Michigan Cardiovascular Center and VA Ann Arbor Healthcare System, in cooperation with the Ohio team.
In all, 67 percent of patients had positive or inconclusive MTWA test results. Of them, the patients who went on to receive an ICD were 55 percent less
Contact: Kara Gavin
University of Michigan Health System