U-M researchers explore far-reaching impacts from new definition of "myocardial infarction"
ORLANDO, FL - One of the most compelling questions regarding the November 2000 hospitalization of Vice President Dick Cheney was whether or not he'd really had a heart attack.
At first, the answer was "no." Then, a check of Cheney's enzyme levels showed he had, in fact, suffered his fourth heart attack.
Why the confusion? It may have been due to the fact that, for the past several years, physicians have been working to pin down the best set of criteria for determining whether a patient has had a heart attack, also known as a myocardial infarction.
In September 2000, a new, widely accepted definition of myocardial infarction was introduced - a definition developed by a joint committee of the European Heart Society and the American College of Cardiology. The most significant change: The definition adds cardiac troponin, an enzyme found only in heart muscle tissue, to the measures already used to determine whether or not a myocardial infarction has occurred.
Researchers at the University of Michigan Health System, including Rajendra Mehta, M.D., clinical assistant professor of cardiology in the UMHS Cardiovascular Center, recently completed a study investigating the significance of this change in definition at UMHS. They found that the new definition will mean a significant increase in the number of myocardial infarction cases at U-M, and implies such an increase nationwide. The information was presented today at the 50th annual Scientific Session of the American College of Cardiology.
"In the United States, nearly a million heart attacks are diagnosed annually," Mehta says. "These data suggest that under the new criteria, 250,000 more will be diagnosed each year. These myocardial infarctions would have been missed by the old criteria." In addition to the far-reaching clinical implications, it's likely that the financia
Contact: Valerie Gliem
University of Michigan Health System