RECOVERY OF LEFT-VENTRICULAR FUNCTION AFTER ACUTE MYOCARDIAL-INFARCTION - EFFICACY OF DOMICILIARY THROMBOLYSIS IN THE GRAMPIAN REGION EARLY ANISTREPLASE TRIAL

Background: The objective was to compare the effect of thrombolytic therapy given either at home or in hospital on the recovery of left ventricular function after acute myocardial infarction. Methods: In a randomized double-blind trial, 311 patients with suspected acute myocardial infarction were given 30 units anistreplase intravenously either at home, or later, in hospital. The median time-saving made with domiciliary thrombolysis was 130 min. All patients were admitted to hospital where left ventricular stroke distance was measured daily using a simple bedside ultrasound technique, and expressed as a percentage of the age-predicted normal value. The last recorded inpatient stroke distance measurement was used to assess residual left ventricular function after recovery from myocardial infarction. Results: The mean stroke distance in patients with confirmed myocardial infarction was 74% on the day of admission, rising to 83% on the last inpatient day; it did not change between discharge and 3 months after admission. For 180 patients assigned randomly to treatment within 2 h of the onset of symptoms, mean stroke distance was greater by 6.8% in those given active anistreplase at home rather than in hospital (95% confidence interval 1.0 to 12.7%, P = 0.02), but there was no significant difference in stroke distance following home or hospital thrombolysis in 111 patients assigned treatment after that time (difference - 2.0%, 95% confidence interval - 8.4 to 4.5%, P = 0.54). Conclusions: The efficacy of thrombolytic therapy is enhanced when administered within 2 h of the onset of symptoms.