Comparative Efficacy and Safety of Coronary Artery Bypass Grafts: Insights from a Systematic Review and Meta-Analysis

AbstractO_ST_ABSIntroductionC_ST_ABSOptimal conduit selection in coronary artery bypass grafting (CABG) remains debated. While the left internal mammary artery (LIMA) is standard, the comparative performance of bilateral internal mammary arteries (BIMA), radial artery (RA), right internal mammary artery (RIMA), and saphenous vein grafts (SVGs) has not been comprehensively established. We performed a meta-analysis of observational studies to evaluate the efficacy, safety, and outcomes of different coronary grafts. MethodsA systematic search identified 795 studies, of which 32 observational studies comprising 172,911 patients were included. Data were pooled using random-effects models in STATA. Outcomes included survival, graft occlusion, graft failure, patency, revascularization, mortality, adverse events, wound infection, length of stay, and renal function. ResultsA total of 32 observational studies involving 172,911 patients (69,402 male and 100,658 female; mean follow-up 105.1 months) were included. The most frequently used conduit was the LIMA (66,135 patients), followed by SVG (48,892), BIMA (20,133), RA (8,516), RIMA (2,305), LIMA+SVG (2,339), and LIMA+RA (60). BIMA grafting was associated with significantly improved survival (log OR -0.68; 95% CI -0.93 to -0.44) and reduced graft failure (-0.67; 95% CI -1.02 to -0.32), whereas SVGs demonstrated worse survival (-3.94; 95% CI -4.07 to -3.82) and lower patency (-4.00; 95% CI -4.44 to -3.56). RA grafts reduced cardiac mortality (-1.30; 95% CI -1.89 to -0.71) and adverse events (-0.69; 95% CI -1.09 to - 0.28), while RIMA was associated with increased graft failure (2.50; 95% CI 1.47-3.52) and higher all-cause mortality (1.09; 95% CI 0.60-1.58). SVGs lowered the risk of sternal wound infections (-1.77; 95% CI -2.61 to -0.92), while BIMA showed a nonsignificant increase. BIMA also shortened hospital stay (-0.83 days; 95% CI -1.45 to -0.20). No significant differences were observed across conduits for renal dysfunction. ConclusionThis meta-analysis confirms the superiority of arterial grafts, particularly BIMA and RA, in enhancing survival and reducing adverse outcomes compared with SVGs. LIMA remains the cornerstone graft, while the use of multiple arterial grafting strategies provides durable long-term benefits. Careful patient selection is essential, particularly given the higher wound complication risk with BIMA and variable outcomes with RIMA. These findings reinforce the growing role of total arterial revascularization, though further randomized trials are warranted to refine graft selection strategies.