Multiple Marker Test Quickly Shows Heart Attack Risk

A multicenter study has found that combining tests seldom used together, and analyzing them much more quickly than is typical, identified many more patients at high risk for a heart attack significantly earlier than standard laboratory testing. The study, conducted by researchers at Duke University (Durham, NC, USA) and five other U.S. medical centers, was presented at the 22nd Annual Congress of the European Society of Cardiology, in Amsterdam (The Netherlands).

The study involved around 1,000 patients who came to emergency rooms complaining of chest pain. A test of two chemical markers of heart damage, completed in about 15 minutes, identified 114 patients with evidence of heart damage, while an even more sensitive combination of three markers found 149 positive patients, including three who died. There were no deaths among patients with negative results.

In comparison, the standard laboratory test given to the same 1,000 patients identified 44 patients at risk, none of whom later died. The average time that elapsed until test results were available was about three hours. The standard test did not identify the three patients who died and who were identified by the triple combination test.

To identify heart patients at high risk of dying, hospitals commonly use one of several blood tests that include creatine-kinase MB (CK-MB), a cardiac troponin, or a test of myoglobin. The researchers note that the first two tests can take six to eight hours to show results, while myoglobin appears in blood much faster and so can be used to assess early heart damage. Some hospitals use two of these tests, but most use only one. Because of the results found in the new study, the researchers conclude that combining all three tests and quickly analyzing them is the best strategy to find evidence of heart damage and determine the risk for complications.

In the study, the Stratus CS Stat device (Dade-Behring Corp.) was used in the testing because it can analyze results at a patient's bedside within 15-20 minutes. The device has been cleared by the U.S. Food and Drug Administration (FDA).