Plasma beta-thromboglobulin in acute myocardial infarction.

Serial measurements of plasma beta-thromboglobulin concentration were made in 25 patients with acute myocardial infarction. The beta-thromboglobulin level was elevated in 18 patients on the day of presentation and the mean beta-thromboglobulin of the patients (83 ng/ml) differed significantly from the normal mean (26 ng/ml; p less than 0.001). When grouped according to the clinical severity, the most severely affected patients had the highest values (mean 128 ng/ml; n = 11). Two patients with a mild or moderate clinical course had a normal beta-thromboglobulin level throughout the study. The patients showed a distinct pattern in the evolution of the plasma beta-thromboglobulin values. The initial elevation was followed by a decrease in beta-thromboglobulin levels (mean 37 ng/ml on day 3), when only the severely affected patients differed from the normals. The beta-thromboglobulin level started to increase thereafter, reaching in many cases the highest and in some cases the only abnormally high values at the end of the second week (mean 75 ng/ml) in the survivors. The levels were mostly normal again 4-6 months after the infarction.