An algorithm for prehospital thrombolysis in acute MI

The gain in survival by thrombolytic therapy in patients with myocardial infarction (MI) is determined by the delay between coronary occlusion and reperfusion. Patient selection requires electrocardiogram (ECG) confirmation of extensive myocardial ischemia. In the REPAIR study a small portable ECG computer system is used to analyze the ECG `on the spot´. A specially developed algorithm is used to identify patients who would benefit most from at-home thrombolysis. Of 1251 ECGs of patients with chest pain, made by the ambulance service, 188 met the criteria for prehospital treatment. These patients could be treated within 23 ± 9 minutes after ambulance arrival. The time gained averaged 47 minutes. There were four false-positive diagnoses (false-positive ratio 0.3%). Specificity was 99.6%, whereas sensitivity in overall detection of infarction was 54%. Computer aided analysis of an ECG made on the spot proves to be both fast and reliable, making rapid initiation of at-home thrombolytic therapy possible