Transluminal coronary angioplasty (TCA) has become the treatment of choice of residual stenosis after thrombolysis for myocardial infarction, but the long-term results of TCA are imperfectly evaluated. Seventy patients underwent TCA after thrombolysis on account of a significant (greater than 50 p. 100) residual stenosis of the artery responsible for the infarction. TCA was performed less than 6 hours after the onset of symptoms in 15 patients who had neither clinical nor electrocardiographic evidence of reperfusion; 4 of these patients were in a state of cardiogenic shock. In the remaining patients TCA was performed 1 to 10 days (mean 3.2 days) after thrombolysis. A primary success was obtained in 64 patients (91 p. 100). Two patients had emergency aorto-coronary bypass. During their stay in hospital, 5 patients presented with symptoms of reocclusion which in 4 of them occurred less than 24 hours after TAC, and 2 of these 4 patients had to be reoperated upon; 2 patients died suddenly. During a 6 to 18 months' follow-up period (mean 10.5 months), the infarction recurred in 3 patients; the recurrence took place during the 3rd month in 2 of them (1 had another thrombolysis and later TAC) and during the 6th month in the third one. At 6 months, 4 patients were suffering from exertion angina and 2 asymptomatic patients had a positive exercise test. Fifty-two control coronary arteriographies were performed at 6 months. Thirteen patients (25 p. 100) had an occluded artery which was clinically silent in 11; 39 patients had a patent artery with restenosis in 7.(ABSTRACT TRUNCATED AT 250 WORDS)