RIMA-SVG versus Ao-SVG in coronary artery bypass grafting: protocol for a prospective, randomised, double-blind, non-inferiority and single-centre trial.

Abstract

Introduction: Coronary artery bypass grafting (CABG) is a standard treatment for coronary artery disease, particularly in patients with multivessel disease. Connecting the saphenous vein graft (SVG) to the right internal mammary artery (RIMA) instead of the aorta has been proposed as an alternative approach to minimise aortic manipulation and potentially improve graft patency. This study aims to determine whether the RIMA-SVG technique is non-inferior to the conventional Aorta (Ao)-SVG approach in terms of 1-year graft patency, while also comparing perioperative complications and short-term clinical outcomes.

Methods and analysis: This non-inferiority, single-centre, prospective, double-blind, randomised clinical trial will enrol 300 patients undergoing CABG. Participants will be randomised into two surgical groups (RIMA-SVG vs Ao-SVG). The primary outcome is the 1-year SVG patency rate, assessed using coronary CT angiography. Secondary outcomes include perioperative complications, all-cause mortality, major adverse cardiovascular and cerebrovascular events (MACCE), and surgical site infections occurring during hospitalisation and up to 1 year postoperatively. Randomisation will be computer-generated, and all procedures will be performed by experienced surgeons. Patients will be followed up 12 months post-surgery. Non-inferiority will be established if the upper bound of the one-sided 97.5% CI for the difference in graft occlusion rates is less than the prespecified non-inferiority margin of 10%.

Ethics and dissemination: This study has been approved by the Ethics Committee of the Second Hospital of Jilin University (No. 460) and registered at ClinicalTrials.gov (NCT06787651). All participants will provide written informed consent before enrolment. To ensure data integrity and minimise bias, randomisation details will be concealed from researchers until surgery, and data analysts will remain blinded to group assignments. The findings will be disseminated through academic journals and conference presentations to promote knowledge sharing and clinical application in the field of cardiovascular surgery.

Trial registration number: NCT06787651.