Cardiac devices approved without scrutiny

SAN FRANCISCO, Dec. 31 (UPI) -- Cardiovascular devices are often based on studies that lack adequate strength or may have been prone to bias, U.S. researchers say.

Dr. Sanket S. Dhruva of the University of California, San Francisco, and colleagues analyzed the type and quality of study evidence used by the Food and Drug Administration for the pre-market approval of cardiovascular devices.

These types of devices were included in the study because it was expected they would undergo the most stringent approval process, given their increasing usage and potential impact on illness and risk of death.

"In 2008, at least 350,000 pacemakers, 140,000 implantable cardioverter-defibrillators, and 1,230,000 stents were implanted," study authors said in a statement.

The authors conducted a systematic review of 123 summaries of safety and effectiveness data for 78 pre-market approvals for high-risk cardiovascular devices that received pre-market approval between January 2000 and December 2007, examining the methodological characteristics and primary end points.

The study, published in the Journal of the American Medical Association, found that of nearly 80 high-risk devices, the majority received approval based on data from a single study.