ABSTRACT
INTRODUCTION: Use of the left internal mammary artery to bypass the left anterior descending coronary artery reduces cardiac events and increases survival. However, there is some controversy as to the benefits of using both mammary arteries. OBJECTIVES: To assess the long-term outcome of the use of both mammary arteries in comparison with the use of only one. PATIENTS AND METHOD: A retrospective cohort study with a mean follow-up of 9.0 +/- 4.2 years was performed including 108 patients consecutively revascularized using both mammary arteries (II) and 108 patients randomly chosen in whom one mammary artery (I) was used for this purpose. RESULTS: Both groups were similar. There were no differences between the groups in operative morbidity or mortality. The survival at 10 years was similar (II: 84.61 +/- 4%; I: 85.18 +/- 3.8%), whereas recurrence of angina (II: 29.63 +/- 5.3%; I: 47.55 +/- 5.6%) (p = 0.012), the requirement for percutaneous angioplasty (II: 3.98 +/- 2%; I: 12.99 +/- 4.1%) (p = 0.009) and cardiologic events (II: 33.48 +/- 5.5%; I: 48.48 +/- 5.5%)(p = 0.022) were all lower in the group in which both mammary arteries were used. In the multivariate analysis, the use of both mammary arteries was an independent protective factor against angina recurrence (RR = 0.55), angioplasty (RR = 0.18) and cardiologic event (RR = 0.60). CONCLUSIONS: The use of both mammary arteries for revascularization does not increase operative morbidity. Since this procedure acts as an independent factor against angina recurrence, angioplasty and cardiologic event