ICDs Have a Higher Malfunction Rate than Pacemakers

Photo: A pacemaker device

William H. Maisel, M.D., M.P.H., of Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, and colleagues from the U.S. FDA analysed the manufacturer’s pacemaker and ICD annual reports for the years 1990-2002 to determine the reported number, rate, and reasons for pacemaker and ICD malfunctions and to assess trends in their performance.

The researchers found that from 1990 to 2002, 2.25 million pacemakers and 415,780 ICDs were implanted in the United States. During this period, 17,323 devices (8,834 pacemakers and 8,489 ICDs) were explanted due to confirmed malfunction. The average annual total device malfunction replacement rate was 6.8 per 1,000 device implants. Overall, the annual average ICD malfunction replacement rate was significantly higher than the pacemaker malfunction replacement rate (20.7 vs. 4.6 replacements per 1,000 implants). Battery/capacitor abnormalities and electrical issues accounted for half of the total device failures. Sixty-one deaths (30 pacemaker patients, 31 ICD patients) were attributable to device malfunction.

The researchers write that because ICDs are substantially more sophisticated than pacemakers, it is not surprising that they have a higher device malfunction replacement rate. “Routine device checks at regular intervals remain the best way for physicians to monitor ongoing device performance in individual patients. Technological advances that allow for remote wireless monitoring or monitoring via the Internet may become increasingly important. Despite this newly recognized increase in ICD malfunction replacement rate, ICDs effectively reduce mortality in specific high-risk populations. These devices have prevented innumerable sudden deaths, and they remain an important therapy for patients at high risk for sudden cardiac death,” the authors write.

COMPAMED.de; Source: American Medical Association (AMA)