Background: Thrombolytic therapy results in reperfusion of the occluded coronary vessel in approximately 75% of treated patients with acute myocardial infarction (AMI). Unsuccessful thrombolysis results in impaired outcome. This study was undertaken to evaluate reperfusion assessments with 12-lead standard static electrocardiography (ECG) and continuous vectorcardiography (VCG) in AMi patients treated with thrombolytic therapy, with particular emphasis on the value of these assessments in relation to long-term outcome. Methods: ST-recovery analysis 90 and 180 min after the start of thrombolytic therapy was performed by repeated ECG and by VCG in 63 AMI patients. Median follow-up was 255 days. Results: No significant differences in long-term outcome were found between patients with or without obtained reperfusion, as assessed by ECG. For VCG, we found significant elevated relative risks for experiencing death (relative risk: 11.00, confidence interval = 2.70-44.90); P = 0.0008 for the group with ST-vector magnitude recovery of less than 50% at 90 min from start of thrombolytic therapy. Conclusion: We demonstrated that early reperfusion assessment with VCG enables the prediction of long-term outcome and is superior to reperfusion assessment with standard static ECG in this regard. We therefore recommend continuous ischemia monitoring of AMI patients treated with thrombolytic therapy as a routine procedure.