A Double-Vessel Coronary Artery Bypass Grafting Porcine Model using Autologous Internal Mammary Veins

The saphenous vein is one of the most commonly used conduits in coronary artery bypass grafting (CABG). However, the high long-term failure rate limits its clinical efficacy. Although hemodynamic factors are widely believed to drive vein graft failure (VGF), the exact underlying mechanisms remain unclear. Currently, the rat common carotid artery interposition vein graft model serves as the primary animal model for investigating VGF. However, substantial differences in cardiovascular physiology and hemodynamics between rats and humans limit the clinical translation of research findings. Pigs represent an ideal animal model for cardiovascular research because their cardiovascular anatomy and physiology closely resemble those of humans. In this study, three double-vessel CABG porcine models were established using autologous left and right internal mammary veins (IMVs), with one graft anastomosed from the aorta to the left anterior descending coronary artery (LAD) and the other from the aorta to the left circumflex coronary artery (LCX). Intraoperative ultrasonography confirmed flow in both IMV grafts in a representative animal, whereas postoperative computed tomography angiography (CTA) clearly demonstrated patency of the aorta-to-LAD IMV graft. Therefore, this study describes a technically feasible approach for establishing a large-animal CABG model for future studies of VGF.