Functional integrity and aging of the left internal thoracic artery after coronary artery bypass surgery

Abstract Objective: To study the endothelial function in the left internal thoracic artery after coronary artery bypass surgery and to identify predictors of early dysfunction, we performed a provocative test with acetylcholine in 23 male patients who underwent routine postoperative coronary angiography. Methods: The change in mean diameter of the proximal thoracic artery was assessed by quantitative angiography after selective injections of acetylcholine and nitroglycerin. Results: The thoracic artery showed a 6.8% ( P P R: 0.88; P P =.001), and acetylcholine-induced vasodilation was inversely correlated to the age of the patient ( R: 0.69; P Conclusions: Endothelium-dependent vasodilative response to acetylcholine administration seems well preserved in the left internal thoracic artery after surgery. Common risk factors, except for age, do not affect the functional integrity of the arterial graft. The vasodilative properties of the graft depend on the age of the patient and do not deteriorate over time after operation. (J Thorac Cardiovasc Surg 2000;120:313-8)