Left ventricular thrombi diagnosed by echocardiography in patients with acute myocardial infarction treated with intracoronary streptokinase followed by intravenous heparin.

Thirty patients with acute myocardial infarction (AMI) treated with intracoronary streptokinase (7 X 10(5) +/- 3 X 10(5) IU) followed by 10 days of intravenous heparin (800 to 1,500 IU/hour) therapy were prospectively studied by serial 2-dimensional echocardiography for left ventricular (LV) thrombus. Within the first 24 hours, evidence of a thrombolytic state appeared as indicated by fibrin and fibrinogen degradation products (123 +/- 45 mg/dl at 24 hours). Throughout the course of this study partial thromboplastin times were maintained within therapeutic range (40 to 100 seconds). Apical LV thrombus developed in 8 of 30 patients (27%). Apical thrombus developed within 24 hours in 3 patients with anterior AMI and persisted through day 10. By day 10, apical thrombus developed in 3 additional patients with anterior AMI and 2 patients with inferior AMI. In these patients, anterior AMI and apical dysfunction were significant (p less than 0.01 for both) determinants of LV thrombus formation. Hence, the incidence of LV thrombus in patients treated with streptokinase/heparin is similar to that reported earlier in comparable patients not receiving thrombolytic therapy.