Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: THURSDAY, September 1, 1994 TAG: 9409010092
SECTION: NATIONAL/INTERNATIONAL PAGE: A-15 EDITION: METRO
SOURCE: Associated Press
DATELINE: BOSTON LENGTH: Medium
The test typically gives an answer within two hours, not 12 to 24 hours as is now required. If it is used the way its inventors hope, the test could vastly reduce the cost of treating heart attacks by allowing doctors to quickly discharge patients with false alarms.
About 5 million people with chest pain go to emergency rooms each year. While some heart attacks are clearly evident from the start, many are not; and ambiguous cases are routinely admitted to coronary care units until doctors know for sure.
As a result, fewer than 30 percent of those admitted to cardiac intensive care actually turn out to have had heart attacks. These units are often the most expensive in the hospital. Rates can be $2,000 a day.
By helping emergency room doctors keep patients out of intensive care, the new test could lead to big savings.
``We estimate that you could save three or four billion dollars a year using this test,'' said Dr. Robert Roberts, one of the developers at Baylor College of Medicine in Houston.
The Baylor team describes its results from using the test on 1,110 emergency room patients in a report in Thursday's today's issue of the New England Journal of Medicine.
``Had this test been used as a screening test, we would have reduced our coronary care unit admission rate by 70 percent,'' said Dr. Peter R. Puleo, the report's principal author.
Often, doctors can tell by electrocardiograms whether people with chest pain are having heart attacks. But when these readings are normal, they frequently have to wait until blood enzymes reveal whether or not a heart attack has occurred.The heart constantly releases very low amounts of this enzyme, called creatine kinase MB. Levels gradually rise after a heart attack. But typically it takes a day or so before they are high enough for doctors to be sure a heart attack has occurred.
The enzyme begins to break down in the bloodstream soon after its release.
Ordinarily, the blood contains equal amounts of the fresh and degraded versions of an enzyme called creatine kinase MB. Soon after a heart attack, though, the ratio changes: The fresh variety outweighs the degraded type, even though the total amount of enzyme in the bloodstream may still be in the normal range.
By measuring changes in the ratio of these two kinds of enzymes, the new test can reveal with 95 percent certainty whether someone has had a heart attack within six hours after symptoms start.
by CNB