Since percutaneous transluminal coronary angiolplasty (PTCA) was introduced by Gruenzig in 1977, this procedure was extended to the multi-vessel lesion, unstable angina, acute myocardial infarction and old myocardial infarction. We performed coronary angiography and PTCA in 17 patients with evolving acute myocardial infarction for the last 21 months from February 1986 to November 1987 at Severance Hospital, Yonsei University. The result are followings: 1) Fifteen of 17 patients (88.2%) with total coronary occlusion underwent successful PTCA, including 15 patients with and 2 patients without previous intravenous or intracoronary urokinase infusion. 2) One patient (6.0%) died due to cardiogenic shock. 3) The delta area decreasing rate and left ventricular end diastolic pressure (LVEDP) were not improved in the left ventriculogram immediate after PTCA, but the LVEDP was significantly decreased in late follow-up left ventriculogram (Fig. 2,3). 4) In-hospital clinical course was stable in the 15 patients with successful PTCA, but 5 of them (33.3%) had angiographically restenosis during follow-up period of 2 days to 2 months. Two patients with angiographically restenosis and been performed repeat PTCA, one of them was successful. During follow-up period of 7 months (1-20 mos) in 15 patients with sucessful initial PTCA, 13 patients were in functional class I, two was functional class II and no death. 5) The patency rate of infarct-related coronary artery after urokinase infusion was 26.7%. The immediate urokinase effects was not remarkable in this study. These data suggest that successful PTCA with sustained patency of an infarct-related artery has a beneficial effect on the salvage of the jeopardized myocardium. In conclusion PTCA with or without thrombolytic therapy can be carried out with safety and is potentially useful therapeutic procedure in management of selected patients in evolving acute myocardial infarction.