Impact of the Extent of Coronary Artery Disease on Outcomes After Revascularization for Unprotected Left Main Coronary Artery Stenosis

Objectives: This study was designed to examine the impact of the extent of coronary disease on long-term outcomes after coronary stenting or coronary artery bypass graft (CABG) surgery for unprotected left main coronary artery (ULMCA) stenosis. Background: The differential outcome of ULMCA revascularization according to the coronary involvement remains uncertain. Methods: From the MAIN-COMPARE (Revascularization for Unprotected Left Main Coronary Artery Stenosis: Comparison of Percutaneous Coronary Angioplasty versus Surgical Revascularization) registry, 2,240 patients with ULMCA stenosis who underwent either stenting or CABG were stratified by number of diseased vessels. Results: Following adjustment with EuroSCORE (European System for Cardiac Operative Risk Evaluation), diabetes mellitus, and bifurcation stenosis, stents and CABG had similar risks of death and major adverse cardiac events including death, Q-wave myocardial infarction, or stroke in all subgroups regardless of the number of diseased vessels over 4 years. In patients with 2-vessel (23.0% vs. 14.2%; hazard ratio [HR]: 1.739; 95% confidence interval [CI]: 1.171 to 2.582; p = 0.006) or 3-vessel (25.0% vs. 17.6%; HR: 1.493; 95% CI: 1.096 to 2.035; p = 0.011) disease, however, stenting was associated with a higher risk of major adverse cardiac and cerebrovascular events including major adverse cardiac events or target vessel revascularization than CABG. Interaction of vascular involvement with type of stent or CABG was not significant. Conclusions: Stenting appears to be a safe alternative to CABG in patients having ULMCA stenosis combined with additional vascular disease. The advantage of CABG over stenting lies principally in the reduction of repeat revascularization across subgroups stratified by the number of diseased vessels.