Benefits accruing to grafting of the right internal thoracic artery to the left anterior descending artery in coronary artery bypass grafting.

OBJECTIVES: We have investigated the effects and outcome from grafting the right internal thoracic artery to the left anterior descending artery in coronary artery bypass grafting. METHODS: We analyzed the findings in 185 patients who underwent coronary artery bypass grafting involving right internal thoracic artery-left anterior descending artery bypass. The survival rate, cardiac events related to the right internal thoracic artery-left anterior descending artery graft, and graft patency were investigated. In cardiac catheterization, the production of nitric oxide from the endothelium of the internal thoracic artery was measured as the plasma nitrite and nitrate levels by the Griess reaction. The reactions to acetylcholine infusion (5 micrograms) in the right internal thoracic artery (n = 4) were compared to those in the left internal thoracic artery (n = 9) grafts. RESULTS: The hospital mortality rate was 0.5%. The actuarial survival rate at 11 years after operation was 98.81%. The rate of freedom from cardiac events at 11 years after operation was 92.08%. The rate of patency of the right internal thoracic artery-left anterior descending artery was 97.0% in 133 patients. Nitric oxide production was calculated as (total nitrite plus nitrate production in response to stimulation by acetylcholine-total nitrite plus nitrate level before acetylcholine load)/(total nitrite plus nitrate level before acetylcholine load). There was no significant difference in changes in plasma concentration in response to acetylcholine stimulation between the right internal thoracic artery-left anterior descending artery and left internal thoracic artery-left anterior descending artery groups (20 +/- 29% versus 5 +/- 10%). CONCLUSIONS: The right internal thoracic artery-left anterior descending artery grafts exhibited good patency and release of nitric oxide in response to acetylcholine loading, similar to left internal thoracic artery-left anterior descending artery grafts.