Researchers from the Massachusetts General Hospital report that mitral valve prolapse, an abnormality of a heart valve, does not appear to be associated with an increased risk of stroke among young people. Earlier studies, many using outdated imaging techniques, had led to the belief that mitral valve prolapse was a significant risk factor for stroke.
The MGH report appears in the July 1 New England Journal of Medicine. It accompanies a report from the Framingham Heart Study that found mitral valve prolapse to be much less common in the general population than previously believed and less strongly associated with health problems. MGH researchers also were co-authors of the Framingham study, which used techniques developed at the MGH to diagnose mitral valve prolapse accurately.
"As many as 10 to 15 percent of the population have been told they have mitral valve prolapse, that they need to take antibiotics when having dental or other procedures, and that they are at increased risk for stroke, heart failure, heart rhythm abnormalities or other serious problems. Some may have to pay higher insurance premiums because of the diagnosis," says Robert Levine, MD, of the MGH Cardiac Ultrasound Laboratory. "We now know that this condition actually occurs in only about 2 percent of the population." Levine is the senior author of the MGH article and a co-author of the Framingham Study report.
Ferdinando Buonanno, MD, of the MGH Stroke Service, a co-author of the paper, adds, "The studies indicating that mitral valve prolapse was a risk factor for stroke were based on criteria that overdiagnosed the condition in both healthy patients and those who had experienced strokes. It now appears that even those with true mitral valve prolapse have no increased risk of stroke."
The mitral valve - one of four valves controlling the flow of blood through the
heart - lies between the left atrium, which receives oxygenated blood from the
lungs, and the left ven
Contact: Susan McGreevey
Massachusetts General Hospital