Experience with intracoronary streptokinase in 36 patients with acute evolving myocardial infarction

Acute angiography was performed in 36 consecutive patients withevolving myocardial infarction admitted within 3 h after onsetof symptoms. No fatal complication occurred. Angiography revealeda total occlusion in 32 patients (89%), a subtotal stenosisin three (8%), and a 90% stenosis in one patient (3%). Anteriorinfarction was exclusively related to left anterior descending,and inferior infarction to right coronary or circumflex obstruction.After identification of the ‘infarct-vessel’, nifedipine10 mg was administered sublingually. In no patient was anterogradeflow affected with this treatment. In 35 patients an attempt to lyse clot was made with intracoronarystreptokinase; an infusion of 2000–4000 U/min, precededby a bolus of 10 000–20 000 U was infused into the ‘infarct-vessel’. In 26 patients (74%) reperfusion was achieved, two combinedwith guidewire perforation. The mean duration of onset of symptomsto reperfusion was 3.6 h (range 1.8–5.6). The mean durationof lysis was 1.2 h (range 0.3–3), and the mean dosageof streptokinase was 200 000 U (50 000–400 000 U]. In25 out of 26 patients (96%) a high degree of obstruction remainedimmediately after lysis and at repeat angiography 6–8weeks after the acute event. Despite treatment with aspirin200 mg daily and nifedipine 30 mg daily four re-occlusions occurred.Coronary bypass surgery was performed electively in five patients. Thus, we conclude that in patients with evolving myocardialinfarction, the infarct-vessel can be recanalized in 74% ofpatients by intracoronary streptokinase. The true benefit ofthis treatment must await a controlled study.