Impact of double internal thoracic artery grafts on long-term outcomes in coronary artery bypass grafting.

We performed this study to determine if bilateral internal thoracic artery grafts provide greater benefit than single internal thoracic artery grafts. Six hundred ninety-four consecutive patients who received 2 coronary grafts in a single operation during 1983-1989 were given 10 years of follow-up and then analyzed retrospectively. Group 1 (n=382) received 2 internal thoracic artery grafts, Group 2 (n= 139) received 1 internal thoracic artery graft and 1 saphenous vein graft, and Group 3 (n= 173) received 2 saphenous vein grafts. Patient demographics, preoperative angiographic findings, and operative indications were the same. Hospital mortality rates were 2.6%, 2.2%, and 2.3%, respectively. Hemorrhage, sternal wound infection, mediastinitis, sternal dehiscence, and prolonged ventilatory support showed no group differences. Follow-up over 10 years was complete in 677 survivors. Mortality rates during follow-up were 1.8%, 2.9%, and 4.7%, respectively. Cardiac-related mortality rates were 71%, 75%, and 88%, respectively (Group 1 vs Group 3, P=0.0412). Ten-year survival was better for Group 1 than for Groups 2 and 3 (P=0.0356 and P <0.0001). Cardiac-event-free survival at 10 years was 93% in Group 1, 84% in Group 2, and 74% in Group 3 (all P <0.0001). The use of 2 internal thoracic artery grafts resulted in significantly lower risk of cardiac death and re-intervention, compared with the use of 1 internal thoracic artery, which in turn was superior to the use of vein grafts. Use of double internal thoracic arteries did not increase postoperative complications.