EVALUATION OF A NEW BIOLOGICAL ASSAY FOR EMERGENCY QUANTIFICATION OF SERUM MYOGLOBIN

The usefulness of a nephelometric-based serum myoglobin assay kit in t he early diagnosis of acute myocardial infarction was assessed in 92 c onsecutive patients admitted within 24 hours of the onset of spontaneo us chest pain lasting greater than or equal to 20 minutes. The dischar ge diagnosis was acute myocardial infarction in 37 patients (40.2%), m yocardial infarction lasting greater than or equal to 6 hours in 10, a nd no myocardial infarction in 45 (48.9%). The characteristic curve sh owed that the best differential diagnostic value was a serum myoglobin greater than or equal to 130 mu g/l (sensitivity, 75.6%; specificity, 91.7%; positive-predictive value, 88%; negative-predictive value, 82% ). The initial diagnosis was doubtful in 33 patients (36%) because of an inconclusive electrocardiogram. A serum myoglobin value of greater than or equal to 130 mu g/l would have identified 9 of the 13 patients with acute myocardial infarction and all of the 20 patients without m yocardial infarction, giving an accuracy of 84.8%. These results sugge st that this new rapid, quantitative serum myoglobin assay would be us eful in the evaluation of suspected myocardial infarction, especially in patients with an inconclusive electrocardiogram.