Percutanous transluminal coronary angioplasty (PTCA) was performed in 190 patients with 250 diseased vessels and 278 lesions from Dec. 1987 to Feb. 1994. All the patients had unstable angina (UA). There were 52 (18.7%) type A lesions, 175 (62.9%) type B lesions and 51 (18.3%) type C lesions. Of the 190 patients undergoing PTCA, 134 (70.5%) patients had dilatation of a single vessel, 46 (24.2%) of two vessels and 10 (5.3%) of three or more vessels. In 121 patients with multivessel disease, 98 (81.0%) had incomplete revascularization of the ischemia-related vessel (the culprit vessel) and only 23 (19.0%) had complete vessel revascularization. Kissing balloon technique was used in six patients and autoperfusion balloon in five. There were four patients undergoing directional coronary atherectomy (DCA) and four intracoronary stent. The clinical (patient) success rate was 94.7% (180/190) and technical (vessel) success rate 95.2% (238/250). The average degree of vessel stenosis was 88.7% +/- 8.3% before PTCA and the residual tenosis was 17.9% +/- 9.2% after PTCA. Acute vascular complications occurred in 18 (6.5%) lesions. 15 were managed successfully, two developed Q wave myocardial infarct and one died. None needed emergency coronary bypass operation. PTCA was not successful in 10 patients. In 180 patients with successful PTCA, 165 (91.7%) were free from UA, 15 (8.3%) patients had symptoms improved and oxygen need reduced. During a six-month follow-up, 26 patients had chest pain again with confirmed restenosis, repeated PTCA was performed successfully.