To evaluate medium-term clinical results of two major methods of myocardial revascularization, we compared 80 consecutive patients with multivessel percutaneous transluminal coronary angioplasty (PTCA) with 80 consecutive patients with coronary surgery using both internal mammary arteries in all and additional venous grafts in some. Patients in the surgical group had a higher extent of coronary artery disease. In patients with PTCA a mean of 2.2 vessels per patient were attempted, and in patients with surgery 2.7 distal anastomoses per patient were performed. Primary success for PTCA and surgery was 86% vs 94% and complications occurred in 7% vs 6%, respectively. Control angiograms, done in 86% of patients (59/69) after successful PTCA, showed a recurrence in 42% (25/59). Repeat PTCA was done in 15, elective surgery in seven, and a medical treatment was pursued in 3% patients with restenosis. Recurrence of symptoms after successful surgery was found in three patients (4%). They were treated with PTCA. Clinical follow-up was available for all patients, at a mean of 12 +/- 6 months after PTCA and 16 +/- 9 months after surgery. Mean improvement was 1.5 NYHA functional classes after successful PTCA and 2.1 after surgery; 60% (48/80) vs 89% (48/80), respectively, were in class I (p less than .0001). There were fewer PTCA patients than surgical patients without antianginal drugs at follow-up (19% [11/58] vs 37% [18/48]; p less than .05), and their double product during exercise testing was inferior (272 +/- 56 vs 295 +/- 47 mm Hg X beats/min/100; p less than .05). Medium-term clinical outcome appears better after successful surgery with both internal mammary arteries than after successful multivessel PTCA