Percutaneous coronary intervention for left main stem disease: Impact of diabetes mellitus on mortality

OBJECTIVES: We assessed the impact of diabetes mellitus (DM) on mortality after percutaneous coronary intervention (PCI) for left main stem (LMS) disease. Second, we compared mortality outcomes between non‐insulin treated (NITDM) and insulin treated diabetes (ITDM) in different clinical settings. BACKGROUND: There is a paucity of “real world” outcomes data in diabetic patients undergoing LMS PCI. METHODS: We undertook a retrospective analysis of consecutive patients undergoing unprotected LMS PCI at 2 high volume tertiary centers. Diabetic status and clinical setting for PCI were recorded. The primary outcome measure was all‐cause 30‐day and long‐term mortality (up to 36 months) post index PCI. RESULTS: Between 2003 and 2017, 2,675 patients undergoing index LMS PCI were analyzed. Of those, 77.1% were non‐DM, 15.8% NITDM, and 7.1% ITDM. Overall, DM status was not associated with higher 30‐day mortality (OR 1.39, 95% CI 0.89–2.16, p = .15). During a median follow‐up of 36 months, there was a borderline statistical association of DM with long‐term mortality in all PCI settings (HR 1.31, 95% CI 1.00–1.71, p = .05). Compared to non‐DM, ITDM but not NITDM was associated with short‐ and long‐term mortality in all clinical presentations. CONCLUSIONS: Overall, DM did not impact on 30‐day mortality and had only a borderline statistical association with long‐term mortality. It did not have an influence on mortality in non‐emergency LMS PCI. The impact of DM on mortality outcomes following LMS PCI was only significant in the insulin treated patients.