INITIAL HEPARIN THERAPY IN ACUTE MYOCARDIAL INFARCTION.

The administration of heparin during the first 48 hours following acute myocardial infarction is widely practised. Heparin treatment is also recommended for acute coronary insufficiency on the grounds that it may prevent development of an impending myocardial infarction. These measures had been accepted without support of a controlled clinical trial. By random selection, 101 patients hospitalized with a provisional diagnosis of acute myocardial infarction received heparin (100 mg. intravenously every eight hours for 48 hours) and 105 patients were assigned to a control group. Both groups of patients received bishydroxycoumarin (Dicumarol). The mortality in the heparin series was 30% and in the control group, 28%. A significantly large number of the heparin-treated patients developed clinical and laboratory proof of recent myocardial infarction. It is concluded that early intermittent intravenous heparin treatment does not lower the mortality in patients with acute myocardial infarction nor does it prevent impending myocardial infarction in patients with acute coronary insufficiency.