Usefulness of the presenting electrocardiogram in predicting successful reperfusion with Streptokinase in acute myocardial infarction

The presenting electrocardiogram may contain information indicating the pro bability of successful reperfusion. The relation between 3 parameters in th e presenting electrocardiogram (pathologic Q waves, T-wave inversion, and t he slope of ST elevation) and Thrombolysis in Myocardial Infarction trial ( TIMI) grade 3 flow in the infarct-related artery was assessed angiographica lly 90 minutes after beginning streptokinase in 362 patients. TIMI grade 3 flow was more common in patients without Q waves (55%) than in those with Q waves (35%; p < 0.001), and more common in patients without T-wave inversi on (50%) than in those with T-wave inversion (30%; p < 0.002). There was no relation between the slope of the ST segment or the magnitude of ifs devia tion and the achievement of TIMI grade 3 flow. Only 20% of the 59 patients with both Q waves and T-wave inversion had TIMI grade 3 flow, compared with 50% of the remaining patients (p < 0.0001). Among patients treated within 3 hours, TIMI grade 3 flow was seen in 68% of those without versus 44% of t hose with Q waves (p < 0.01), and in 62% of those without versus 43% of tho se with T-wave inversion (p = 0.06). Among patients treated after 3 hours, TIMI grade 3 flow was seen in 38% of those without versus 30% of those with Q waves (p = NS), and in 38% of those without versus 23% of those with T-w ave inversion (p < 0.05). On multivariate analysis, the absence of Q waves, the time from the onset of chest pain to treatment, and age were independe nt predictors of TIMI grade 3 flow. Pathologic Q waves in the presenting el ectrocardiogram provide valuable information as to the probability of achie ving successful reperfusion following administration of streptokinase, and may be helpful for triage of patients to alternative reperfusion strategies , including percutaneous revascularization. (C) 1999 by Excerpta Medica, In c.