Contemporary Outcomes Following Coronary Artery Bypass Graft Surgery for Left Main Disease

Abstract

Background: Although results of percutaneous coronary intervention (PCI) have been steadily improving, whether surgical outcomes have improved over time is not fully elucidated.

Objectives: This study sought to compare the current outcomes of patients undergoing coronary artery bypass grafting (CABG) with prior surgical results, in the context of randomized trials including the left main (LM) coronary artery stem.

Methods: The authors performed a propensity-matched analysis of patients randomized to CABG in the SYNTAX (Synergy Between PCI With Taxus and Cardiac Surgery) (enrollment period 2005 to 2007) and EXCEL (Evaluation of XIENCE Versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization) (enrollment period 2010 to 2014) trials. All patients had left main (LM) disease with or without multivessel disease. Adjustment was based on 15 clinical and angiographic variables, including anatomic SYNTAX score, with a 2:1 ratio for the EXCEL and SYNTAX trials, collectively analyzing 909 subjects (n = 580 and n = 329, respectively). The primary endpoint was the composite of all-cause death, myocardial infarction (MI), stroke, or ischemia-driven revascularization at 3 years.

Results: Baseline characteristics, anatomic SYNTAX score, number and types of grafts, and duration of hospitalization for the procedures were similar in both groups. CABG procedures in the EXCEL compared with the SYNTAX trial were more often off-pump (29.6% vs. 15.4%; p < 0.001), and guideline-directed medical therapies were used more frequently in the EXCEL surgical cohort. The primary endpoint occurred in 14.0% and 20.9% (p = 0.008) of patients in the EXCEL and SYNTAX trials, respectively. With the exception of MI (4.1% vs. 3.7%), all nonhierarchical events tended to contribute to the improved outcomes in the more recent trial: all-cause death (5.5% vs. 8.5%), stroke (3.1% vs. 5.1%), and ischemia-driven revascularization (7.1% vs. 9.4%) in the EXCEL and SYNTAX trials, respectively.

Conclusions: Over a 5- to 7-year period, significant improvement in event-free survival after surgical revascularization for LM disease at 3 years was noted between the SYNTAX and EXCEL trials, consistent with improving results with cardiac surgery over time. (Synergy Between PCI With Taxus and Cardiac Surgery [SYNTAX]; NCT00114972; Evaluation of XIENCE Versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization [EXCEL]; NCT01205776).

Keywords: coronary artery bypass graft; drug-eluting stents; left main coronary artery disease.