Reduced incidence of left ventricular thrombi with intravenous streptokinase in acute anterior myocardial infarction: prospective evaluation by cross-sectional echocardiography.

Forty-five consecutive patients with transmural anterior acute myocardial infarction were prospectively studied to determine the effect of intravenous streptokinase on the incidence of left ventricular thrombi. Three patients died. The remaining patients were divided into 2 groups. Group 1 patients (n = 22) received 750,000 units of intravenous streptokinase within 6 hours of onset of symptoms. Neither thrombolytic therapy or anticoagulants were administered to 18 patients in group 2. Cross-sectional echocardiography was performed 8 to 10 days following acute myocardial infarction to detect left ventricular thrombus. Technically satisfactory echocardiography was not possible in 2 patients. Apical akinesia or dyskinesia was observed in all patients. No patient in the treated group developed left ventricular thrombus compared with 8 of 18 (44.4%) in group 2 (P less than 0.05). One patient in the control group sustained an embolic cerebrovascular accident. Thus intravenous streptokinase significantly reduces the incidence of left ventricular thrombus formation in patients of transmural anterior acute myocardial infarction.