Comparative Outcomes of Left Main and Non-Left Main Percutaneous Coronary Intervention from the Excellence in Coronary Artery Disease (XLCAD) Registry.

Background: There are limited comparative data on real-world outcomes of patients undergoing percutaneous coronary intervention (PCI) of the left main (LM) and non-LM coronary arteries.

Methods: 873 consecutive patients undergoing LM PCI (n=256) and non-LM PCI (n=617) were enrolled between September 2019-March 2023 in the Excellence in Coronary Artery Disease (XLCAD) Registry. Primary outcome was 1-year incidence of major adverse cardiovascular events (MACE), a composite of all-cause death, non-fatal myocardial infarction, clinically driven repeat revascularization and ischemic stroke. The secondary outcome was periprocedural (≤30 days) events.

Results: Study cohort included 68% men, mean age 71.9 ± 10.3 in LM and 67.2 ± 11.1 years in non-LM PCI groups (p<0.001). LM PCI patients had significantly greater co-morbidities (diabetes mellitus, hyperlipidemia, prior stroke, prior myocardial infarction, prior coronary revascularization, peripheral artery disease, chronic lung and kidney disease and heart failure) compared with non-LM. Acute coronary syndrome indication was the most prevalent (69%). Mechanical circulatory support was employed in 3.1% LM vs 1% non-LM PCI patients (p=0.026). Mean number of lesions treated were 2.2 ± 1.0 in LM and 1.4 ± 0.6 in non-LM PCI groups (p<0.001). Multivessel PCI was performed in 68.8% LM and 21% non-LM PCI patients (p<0.001). Overall, drug-eluting stent use (96.7%), bifurcation PCI (24.7%) and atherectomy (2.4%) were similar across groups. Technical and procedural success rates were high across groups, however significantly higher in non-LM group. Periprocedural (≤30 days post-procedure) events included mortality in 3.5% LM and 1.5% non-LM PCI (p=0.334) and MACE 4.7% LM vs 2.4% non-LM PCI (p=0.080) groups. One-year MACE was significantly higher in LM vs. non-LM PCI (12.9% vs. 8.4%, respectively; p=0.043), driven mainly by higher repeat percutaneous revascularization in LM group (12.1% vs 6.2%; p=0.003). Mortality at 1-year in LM vs non-LM PCI were 10.2% vs 5.8% (p=0.074).

Conclusion: In a real-world experience, LM PCI is performed in patients with significantly greater comorbidities compared with non-LM PCI, with high procedural success. Thirty-day mortality and 1-year MACE are significantly higher in LM group.