Outcomes of left internal mammary artery with saphenous vein composite graft to bypass the left anterior descending artery: a propensity-matched study

Background: This study aimed to evaluate the early and mid-term outcomes of a novel strategy of using the in-situ left internal mammary artery (LIMA) with the great saphenous vein graft (SVG) to bypass the left anterior descending artery (LAD) in coronary artery bypass grafting (CABG). Methods: A total of 979 patients took part in this retrospective observational study; 83 patients were propensity-score matched to the LIMA + SVG group and 83 to the LIMA - LAD group. Early mortality, postoperative complications, mid-term major adverse cardiovascular and cerebrovascular events (MACCE) were compared among the two matched groups after the procedure. Results: No significant differences in early mortality and postoperative complications rates were detected between the two matched groups. For mid-term outcomes, the incidence of MACCE was slightly higher in the LIMA + SVG group, but there was no significant statistical difference (14.9% vs. 12.8%, hazard ratio =1.20, 95% CI, 0.24 to 7.95; P=0.70) between the matched groups. Computed tomography coronary artery angiography (CTCA) images showed a LIMA + SVG composite graft patency rate of 94% (32/34) 25 months after the procedure. Conclusions: Using the in situ LIMA with SVG to revascularize LAD was associated with comparable early and mid-term outcomes. These findings may provide an alternative emergency strategy when in situ LIMA cannot bypass LAD. Further study needs to be conducted to test longer-term outcomes.