Newer, Better Tests for Heart Attacks

Aug. 27 -- WEDNESDAY, Aug. 26 (HealthDay News) -- Two new European reports should help doctors decide which tests they choose to use for diagnosing possible heart attacks in emergency room patients, cardiologists say.

Both studies, which appear in the Aug. 27 issue of the New England Journal of Medicine, looked at tests for troponin, a protein released by damaged heart cells. Standard practice in most hospitals now calls for a troponin test when a heart attack or other major coronary problem is suspected, with a variety of tests commercially available for two forms of the protein, designated troponin I and troponin T.

One of the studies, done primarily in Switzerland, compares the accuracy of four new tests with that of a widely used older assay. The other, led by German physicians, compares tests done for the I and T forms of troponin.

"Both of these studies show that newer assays that are becoming available have a much better sensitivity, detecting even smaller amounts of damage," said Dr. E. Magnus Ohman, director of the program for advanced coronary disease at Duke University. Ohman, an expert on coronary diagnosis, was not involved with either study.

But because of the newness of the tests, "most physicians are uncertain about how they should be used," Ohman explained. The new tests will be a matter of intensive discussion by representatives of the American Heart Association, the American College of Cardiology and the European Society of Cardiology at a meeting in Barcelona next week, he added.

The German study compared newer tests of the two forms of the protein with older tests now widely used in suspected heart attacks. The study of 1,818 cases found that the newer troponin I test was more sensitive in detecting heart damage and more specific in determining that the damage was due to a heart attack, a group led by Dr. Stefan Blankenberg of the University Medical Center Mainz reported.

The troponin I test was better than 90 percent sensitive in detecting heart damage and 90 percent specific in determining whether it was due to a heart attack, the study found.