Comparison of Outcomes of Coronary Artery Bypass Grafting Using Internal Mammary Graft Versus Percutaneous Coronary Intervention for Isolated Proximal Left Anterior Descending Narrowing

There are limited contemporary studies comparing coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) for isolated proximal left anterior descending (LAD) disease. Increasing stent length and decreasing stent diameters are associated with increased risk of restenosis and adverse outcomes after PCI. Whether these parameters influence outcomes when comparing CABG and PCI is unclear. We compared CABG and PCI in 3,473 patients who underwent revascularization for isolated proximal LAD disease from 2004 to 2015 at Harefield Hospital, UK; 3,078 patients (89%) had PCI and 384 patients had CABG (11%). We analyzed all-cause mortality at 3 years. The unadjusted mortality rates were similar (PCI vs CABG: 9.5% vs 7.0%, p = 0.109). PCI was associated with comparable mortality (hazard ratio [HR] 1.15, 95% confidence interval [CI] 0.70 to 1.89, p = 0.593), even when stratified to bare-metal stents (HR 1.58, 95% CI 0.89 to 2.80, p = 0.121); first-generation drug-eluting stents (FDES; HR 1.16, 95% CI 0.67 to 2.02, p = 0.597); and second-generation DES (SDES; HR 0.98, 95% CI 0.53 to 1.82, p = 0.946). Stent diameters did not influence outcomes, but PCI was associated with higher mortality when stent length ≥30 mm (HR 2.12, 95% CI 1.12 to 4.03, p = 0.022). There was a linear association between stent length and mortality, and for every 1-mm increase in stent length, the 3-year mortality increased by 0.32%. In conclusion, for patients with isolated proximal LAD disease, PCI and CABG were associated with similar mortality. Increasing stent length was progressively associated with worse outcomes with PCI. For longer segments of disease requiring stent lengths ≥30 mm, CABG may be associated with better outcomes.