When a “culprit lesion” can be identified in a patient with unstable angina, it may be possible to achieve clinical improvement with incomplete revascularization. We analyzed actuarial survival free of an event (severe angina, myocardial infarction, coronary artery bypass graft, or death) at 6, 12, 18, and 24 months in 83 patients with multi‐vessel disease and unstable angina who had undergone successful percutaneous transluminal coronary angioplasty (PTCA); revascularization was complete in 31 patients and incomplete in 52. Event‐free survival in 85 patients with single‐vessel disease and unstable angina who had undergone successful PTCA also was analyzed. Event‐free survival at 24 months was worse in the multivessel disease patients than in the single‐vessel disease patients (62% vs 85%; P = 0.001). Multivessel disease patients with complete revascularization had the same event‐free survival as those with incomplete revascularization (63% vs 61%; P NS). Diagnostic angiograms revealed thrombus or an irregular ulcerated lesion in 42 of the multivessel disease patients. The event‐free survival of these 42 patients was not different from that of the multivessel disease patients as a whole (64% vs 60%; P NS). We conclude that in patients with multivessel disease and unstable angina the event‐free survival after PTCA is poorer than in patients with single‐vessel disease and unstable angina. In the former patients, event‐free survival does not necessarily depend on the completeness of revascularization. The outcome of patients who have intra‐coronary thrombus or an irregular ulcerated lesion resembles the outcome of patients who lack these findings. (J I