Background: The EXCEL trial reported similar five-year rates of the primary composite outcome of death, myocardial infarction (MI), or stroke after percutaneous coronary intervention (PCI) compared with coronary artery bypass grafting (CABG) for treatment of obstructive left main coronary artery disease (LMCAD).
Aims: We sought to determine whether these outcomes remained consistent regardless of geography of enrolment.
Methods: We performed a prespecified subgroup analysis based on regional enrolment.
Results: Among 1,905 patients randomised to PCI (n=948) or CABG (n=957), 1,075 (56.4%) were recruited at 52 European Union (EU) centres, and 752 (39.5%) were recruited at 67 North American (NA) centres. EU versus NA patients varied according to numerous baseline demographics, anatomy, pharmacotherapy and procedural characteristics. Nonetheless, the relative rates of the primary endpoint after PCI versus CABG were consistent across EU versus NA centres at 30 days and 5 years. However, NA participants had substantially higher late rates of ischaemia-driven revascularisation (IDR) after PCI, driven predominantly by the need for greater target vessel and lesion revascularisation. This culminated in a significant difference in the relative risk of the secondary composite outcome of death, MI, stroke, or IDR at 5 years (pinteraction=0.02).
Conclusions: In the EXCEL trial, the relative risks for the 30-day and five-year primary composite outcome of death, MI or stroke after PCI versus CABG were consistent irrespective of geography. However, five-year rates of IDR after PCI were significantly higher in NA centres, a finding the Heart Team and patients should consider when making treatment decisions. ClinicalTrials.gov identifier: NCT01205776.