Rationale and design of a Single-center Randomized Trial to Compare the Graft Patency between the Radial Artery and the No-touch Saphenous Vein in Coronary Artery Bypass Grafting Surgery (GRAFT-CAB Study).

BACKGROUND: Previous studies suggested only the radial artery and the No-touch (NT) technique were effective in reducing graft occlusion after coronary artery bypass grafting (CABG) surgery. However, there is no randomized trial comparing these two graft conduits. The optimum second conduit for CABG remains undetermined.

MATERIALS AND METHODS: This study is a prospective, single-center randomized clinical trial, aiming to compare the graft patency between the radial artery and the NT vein graft. All patients undergoing isolated CABG with left internal mammary artery (LIMA) plus at least two additional grafts will be considered eligible. 774 cases (516 in the radial artery group and 258 in the NT vein group) will be enrolled in over 1 to 2 years. Participants will be randomized and allocated to two bypass strategies: the LIMA plus one radial artery and one conventional vein graft, or the LIMA plus two NT vein grafts. The primary outcome is graft occlusion at 1 year after CABG evaluated by CT angiography. The secondary outcomes include graft occlusion at 3 and 5 years and major adverse cardiac or cerebrovascular events at 1, 3 and 5 years follow-ups.

DISCUSSION: This study will define whether or not the NT vein has a lower graft occlusion rate than the radial artery in short and mid-term follow-ups, and provide new evidence for the second conduit choice in CABG surgery.

TRIAL REGISTRATION: ClinicalTrials.gov NCT06014047. Registered on October 15th, 2023.