The Bilateral Internal Mammary Artery in Modern Coronary Revascularization: A Paradigm Shift Driven by Technical Evolution

Background: Despite level-A evidence demonstrating superior long-term survival with bilateral internal mammary artery (BIMA) grafting, its global utilization remains dismally low (<10–15%), largely due to historical concerns over deep sternal wound infections (DSWI) and technical complexity. This underutilization persists even as multi-arterial grafting (MAG) adoption stagnates, with recent North American data showing only 16% of coronary artery bypass grafting CABG procedures utilize more than one arterial conduit. Objective: This review synthesizes contemporary evidence demonstrating that modern surgical refinements—particularly skeletonized “no-touch” harvesting—have effectively mitigated these concerns, enabling wider BIMA application. Methods & Results: Over two decades of institutional experience confirm that skeletonized harvesting preserves sternal perfusion and minimizes DSWI risk, even in high-risk patients. Propensity-matched analyses show significant survival benefits of BIMA grafting across age and comorbidity strata (8-year survival: 67.1% BIMA vs. 58.2% single internal mammary artery (SIMA), p < 0.05), rendering previous contraindications relative rather than absolute. Long-term outcomes demonstrate superior 10-year survival for in situ BIMA compared with SIMA (86.1% vs. 78.6%, p < 0.05). Advanced configurations such as sequential skeletonized grafting are safe and further enhance outcomes. In single-vessel left anterior descending artery (LAD) disease, skeletonized left internal mammary artery (LIMA) continues to outperform percutaneous coronary intervention (PCI), underscoring the unmatched durability of arterial conduits. Conclusions: The technical evolution of conduit harvesting has resolved the “BIMA paradox”. Contemporary evidence supports BIMA grafting as a standard of care for a broad CABG population, offering a durable, lifelong solution for coronary artery disease and warranting renewed guideline emphasis on multi-arterial revascularization.