Optical Coherence Tomography of the Saphenous Vein Graft

Within the first year of coronary artery bypass grafting (CABG) surgery, the saphenous vein grafts have a failure rate of 10 to 25%. Visual inspection of the vein graft conduit is the current standard in determining the quality of the vein segment. However, there may be intraluminal abnormalities that are undetectable via a visual inspection. OCT examination, using the ILUMIEN OPTIS NEXT OCT Imaging system, of endoscopically harvested saphenous vein conduits will indicate such pathology and enable the surgeon to assess the quality of the harvested vein at the intravascular level. This study is designed to demonstrate the superiority of OCT-guided saphenous vein CABG in improving the rates of early VGF and the overall outcome of CABG. The study will follow two randomization arms: OCT-guided saphenous vein CABG (interventional arm) vs. visual inspection-guided saphenous vein CABG (standard of care arm). The analysis of subjects will be with respect to their analyzed group. Following enrollment, participants will be followed for up to 10 years. The primary endpoint is per graft incidence of vein graft failure. The assessment of the vein graft will be conducted via coronary CT angiogram (CCTA) at 12 months. In the case where the participant has unplanned angiogram due to clinical reasons, prior to the 12 months, the condition of the graft will be determined via the angiogram. Unless all target grafts have reached the endpoint prior to the 12 month time point, a CCTA will be required. To achieve the power level of 85% at the significance level of 0.025, 760 patients is the anticipated sample size. Analysis will be conducted at the graft level with a Linear Mixed model to account for any potential patient effects.