Long-term outcomes of coronary artery bypass grafting with the combination of free right internal mammary artery and modified proximal anastomosis: a retrospective study

OBJECTIVES: When a right internal mammary artery is employed as a free graft for aorta-coronary bypass, the small diameter of it may pose technical challenges at the proximal anastomosis. To address this, we developed a dome-shaped configuration of the proximal right internal mammary artery-termed "Pouch technique"-prior to anastomosis to the ascending aorta, aiming to reduce the risk of anastomotic stenosis. This study evaluates the long-term outcomes of coronary artery bypass grafting with the combination of free right internal mammary artery graft and this technique. METHODS: Of 834 patients who underwent coronary artery bypass grafting at our institution between 2014 and 2024, 161 received a free right internal mammary artery graft. Among these, 145 patients were included in the analysis. All included patients underwent proximal anastomosis using Pouch technique. Graft patency was primarily assessed by coronary computed tomography angiography at 1, 5, and 10 years postoperatively. RESULTS: During the follow-up period, six deaths were recorded including the two early postoperative deaths. Major adverse cardiac and cerebrovascular events occurred in 11 patients. Graft-related events were observed in seven patients. At 10-year follow-up, overall survival, and freedom from major adverse cardiac and cerebrovascular events were 93% and 82%, respectively. Cumulative incidence of graft events is 12%. CONCLUSIONS: The combination of free right internal mammary artery graft and Pouch technique demonstrated favourable long-term outcomes with a low incidence of proximal anastomotic complications.