Long-term outcomes after percutaneous coronary intervention (PCI) to an unprotected left main coronary artery (LMCA): 10 year observations from the Melbourne Interventional Group (MIG) registry.

Abstract

Background: Patients with significant LMCA disease usually proceed to bypass surgery. Recent trials concluded PCI may be an acceptable alternative to coronary artery bypass grafting (CABG) in selected patients. We reviewed the MIG experience on unprotected LMCA stenting.

Method: Excluding patients with previous CABG and cardiogenic shock, all consecutive patients undergoing PCI from the MIG registry between 2005-2016 were analysed, comparing those with unprotected LMCA PCI to non-LMCA PCI.

Results: A total of 17468 patients were included with 49 patients (0.28%) having LMCA PCI. Patients with LMCA PCI were on average 10 years older (73.3years vs 63.8years, p<0.001), had more peripheral vascular disease (24.5% vs 5.3%, p < 0.001), insulin dependent diabetes (14.3% vs 5.2%, p = 0.02), chronic lung disease (30.6% vs 9.9%, p < 0.001) and significant renal dysfunction (8.2% vs 2.5%, p < 0.001). Procedural success rates were high in all patients with no significant difference when performed to an unprotected LMCA (97.9% vs 96.2%, p = 0.56). In-hospital mortality following unprotected LMCA PCI is higher (6.1% vs 0.8%, p < 0.001). On multivariate analysis, unprotected LMCA PCI has a HR of 1.60 for long-term mortality (95% CI 0.98-2.60, p = 0.059).

Conclusion : The higher short- and long-term mortality after PCI to an unprotected LMCA is likely secondary to their underlying comorbidities often posing prohibitive surgical risk. However, high procedural success and acceptable long-term survival can be expected with PCI in this high-risk group.