Real-world long-term survival after non-emergent percutaneous coronary intervention to unprotected left main coronary artery - From the Melbourne Interventional Group (MIG) registry.

Background: Current evidence suggests that percutaneous coronary intervention for unprotected left main coronary artery disease (LMPCI) in selected patients is a safe alternative to coronary artery bypass grafting. However, real-world long-term survival data is limited.

Methods: We analyzed 24,644 patients from the MIG (Melbourne Interventional Group) registry between 2005 and 2020. We compared baseline clinical and procedural characteristics, in-hospital and 30-day outcomes, and long-term survival between unprotected LMPCI and non-LMPCI among patients without ST-segment elevation myocardial infarction, cardiogenic shock, or cardiac arrest.

Results: Unprotected LMPCI patients (n = 185) were significantly older (mean age 72.0 vs. 64.6 years, p < 0.001), had higher prevalence of impaired ejection fraction (EF <50 %; 27.3 % vs. 14.9 %, p < 0.001) and lower estimated glomerular filtration rate < 60 ml/min/1.73m (40.9 % vs. 21.5 %, p < 0.001), and had greater use of intravascular ultrasound (21 % vs. 1 %, p < 0.001) and drug-eluting stents (p < 0.001). LMPCI was associated with longer hospital stay (4 days vs. 2 days, p < 0.001). There was no significant difference in other in-hospital outcomes, 30-day mortality (0.6 % vs. 0.6 %, p = 0.90), and major adverse cardiac events (1.7 % vs. 3 %, p = 0.28). Although the unadjusted Kaplan-Meier survival to 8 years was significantly less with LMPCI compared to non-LMPCI (p < 0.01), LMPCI was not a predictor of long-term survival up to 8 years after Cox regression analysis (HR 0.67, 95 % CI 0.40-1.13, p = 0.13).

Conclusion: In this study, non-emergent unprotected LMPCI was uncommonly performed, and IVUS was underutilized. Despite greater co-morbidities, LMPCI patients had comparable 30-day outcomes to non-LMPCI, and LMPCI was not an independent predictor of long-term mortality.