Long-term Outcome of Unprotected Left Main Stenting: A Canadian Tertiary Care Experience

BACKGROUND: Coronary stenting is increasingly used to treat unprotected left main disease in selected patients. However, there is a paucity of data on the long-term outcome of these patients in a Canadian context outside of clinical trials. METHODS: We retrospectively reviewed all provincially-insured patients undergoing left main coronary stenting at a large tertiary referral centre from 2000-2011. Pre-procedural angiograms were reviewed to identify the location of left main disease, and extent of concomitant coronary disease quantified by calculating Synergy Between Percutaneous Coronary Intervention With TAXUS Drug-Eluting Stent and Cardiac Surgery (SYNTAX) scores for each patient. In-hospital death and major adverse cardiac event (MACE) rates were evaluated as were long-term death and MACE rates obtained via linkage of our institutional registry with the Ontario health claims database. RESULTS: Two hundred twenty-one patients underwent unprotected left main stenting with 29 (13.1%) in-hospital death and 34 (15.4%) a MACE. At an average follow-up of 3.1 ± 2.8 years, 109 patients (49.3%) died and 151 (68.3%) experienced a MACE. Higher SYNTAX tertile and use of bare metal rather than drug-eluting stents was associated with increased rates of in-hospital and long-term death. CONCLUSIONS: This study reports, to our knowledge, the largest Canadian cohort of unprotected left main stenting over more than a decade. Coronary stenting was associated with acceptable in-hospital event rates, but poor long-term outcomes, reflecting the higher-risk population traditionally selected for this procedure.