Clinical results of double versus single mammary artery myocardic revascularization: 15 years of follow-up

Introduction. Use of the left internal mammary artery to bypass the left an terior descending coronary artery reduces cardiac events and increases surv ival. However, there is some controversy as to the benefits of using both m ammary arteries. Objectives. To assess the long-term outcome of the use of both mammary arte ries 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 revasc ularized 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 gr oups in operative morbidity or mortality. The survival at 10 years was simi lar (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 percu taneous angioplasty (II: 3.98 +/- 2%; I: 12.99 +/- 4.1%) (p = 0.009) and ca rdiologic events (II: 33.48 +/- 5.5%; I: 48.48 +/- 5.5%) (p = 0.022) were a ll lower in the group in which both mammary arteries were used. In the mult ivariate analysis, the use of both mammary arteries was an independent prot ective 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 no t increase operative morbidity. Since this procedure acts as an independent factor against angina recurrence, angioplasty and cardiologic events, its use appears to be justifiable.