American College of Cardiology

ACC 49th Annual Scientific Session
Late-Breaking Clinical Trials
in Interventional Cardiology (#72)
Wednesday, March 15, 2000 (10:45 a.m.-12:15 p.m.)

(ANAHEIM, CALIF.)—Prosthetic heart valves surgically implanted in some patients to replace one or more of their own diseased valves fall into two broad categories, each with advantages and disadvantages. Now a multicenter, randomized trial encompassing 15 years of follow-up data has revealed new information that promises to enhance the selection of appropriate prosthetic valves for patients with different needs.

In the Veterans Administration Cooperative Study on Valvular Heart Disease, 575 patients at 13 VA medical centers who needed replacement aortic or mitral heart valves were randomly assigned to receive either mechanical or bioprosthetic implants. Mechanical valves, made of metal and plastic, last a long time but demand that the patient take anticoagulant pills every day to discourage clot formation on them. Such clots can detach from the valve and travel to the brain, causing a stroke. Bioprosthetic valves, often made from the heart valves of pigs, do not last as long but also do not promote clots and so don't require blood thinning.

“So the question in our trial was, at the end of 10 to 15 years, which one comes out ahead and for which patients?” said Dr. Shahbudin H. Rahimtoola, of the Keck School of Medicine at the University of Southern California in Los Angeles. Dr. Rahimtoola will present the 15-year follow-up results of the VA cooperative trial on Wednesday, March 15, at 11:30 a.m. at the American College of Cardiology 49th Annual Scientific Session, in Anaheim, Calif.

“The results of this study will provide better guidelines for the proper choice of prosthetic heart valves in adults of different age groups,” said Dr. Rahimtoola.

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