Determinants of graft patency after coronary artery bypass grafting.

Coronary artery bypass grafting (CABG) remains central for multivessel coronary artery disease, but durable benefit depends on graft patency. Patency reflects interacting anatomical, technical, haemodynamic, biological and patient-level determinants. The endothelium offers a useful, metabolically active interface because it regulates vascular tone, thrombosis, inflammation, leukocyte trafficking and repair. This Review examines how conduit choice, harvesting, preservation, anastomotic geometry, target anatomy, operative strategy and comorbidity drive early thrombosis, intermediate intimal hyperplasia and late atherosclerosis. Particular emphasis is placed on oxidative stress, endothelial nitric oxide synthase dysfunction, reduced endothelial nitric oxide (eNO) bioavailability and pathological reactive oxygen species (ROS) signalling. Accordingly, we focus on endothelial nitric oxide synthase (eNOS) dysfunction, reduced eNO bioavailability and pathological ROS signalling, and present an eNO/ROS-centred research framework, requiring local delivery, temporal control and CABG-specific validation.