RESUMEN
Patients and methods: One hundred and eight randomly selected patients who received one mammary artery for myocardial revascularization and 108 patients, matched for prognostic factors, who received two mammary arteries were studied. These patients were followed for a mean of 4 years (range 1 to 12 years). Operative complications, hospital mortality and long term probability of being free of disease were compared in both groups. Results: Operative mortality was similar in both groups (0,9 percent). Patients that received two mammary arteries had a higher frequency of operative wound complications. Long term survival was 84 per cente in patients who received one and 83 per cente in patients who received two mammary arteries. The probabilities of being free of myocardial infarction (92 and 82 percent respectively) and angina (94 and 86 percent respectively) were lower in the later group. Conclusions: Patients who received two mammary arteries had a higher probability of a long term disease free survival than patients who received one mammary artery