Sex Differences in Outcomes After Percutaneous Coronary Intervention or Coronary Artery Bypass Graft for Left Main Disease: From the DELTA Registries

Background Controversy exists over whether sex has significant interaction with revascularization strategy for unprotected left main coronary artery disease. Higher mortality has been reported among women treated with percutaneous coronary intervention compared with coronary artery bypass grafting. Methods and Results The DELTA (Drug-Eluting Stents for Left Main Coronary Artery Disease) and DELTA-2 registries are international, multicentric registries evaluating the outcomes of subjects undergoing coronary revascularization for unprotected left main coronary artery disease. The primary outcome was a composite of death, myocardial infarction, or cerebrovascular accidents. The population consisted of 6253 patients, including 1689 (27%) women. Women were older and more likely to have diabetes and chronic kidney disease than men (P<0.05). At a median follow-up of 29 months (interquartile range 12-49), a significant interaction between sex and revascularization strategy was observed for the primary end point (p(int)=0.012) and all-cause death (p(int)=0.037). Among women, compared with percutaneous coronary intervention, coronary artery bypass grafting was associated with lower risk of the primary end point (event rate 9.5% versus 15.3%; adjusted hazard ratio [AHR], 0.53; 95% CI, 0.35-0.79, P<0.001) and all-cause death (event rate 5.6% versus 11.7% AHR, 0.50; 95% CI, 0.30-0.82) and no significant differences were observed in men. Conclusions In women undergoing coronary revascularization for unprotected left main coronary artery disease, coronary artery bypass grafting was associated with lower risk of death, myocardial infarction, or cerebrovascular accidents whereas no significant differences between coronary artery bypass grafting and percutaneous coronary intervention were observed in men. Further dedicated studies are needed to determine the optimal revascularization strategy in women with unprotected left main coronary artery disease.