A selective depression of tissue plasminogen activator (t-PA) activity in euglobulins characterises a risk group among survivors of acute myocardial infarction.

Among 29 patients recovering from a first-time acute myocardial infarction (AMI) 9 patients suffered reinfarction during a four year follow-up period. The 9 reinfarction patients were found to belong to a subgroup of 17 patients with a selective depression to near zero of euglobulin t-PA activity. None of the group of 12 patients with marked t-PA activity suffered a relapse. Euglobulin fibrinolytic activity as usually assayed did not distinguish between groups with or without relapse.