Outcomes Among Patients Undergoing Distal Left Main Percutaneous Coronary Intervention

Background: Distal left main (LM) coronary artery bifurcation disease increases percutaneous coronary intervention (PCI) procedural complexity and is associated with worse outcomes than isolated ostial/shaft disease. The optimal treatment strategy for distal LM disease is undetermined. We sought to determine whether outcomes after PCI of LM distal bifurcation lesions are influenced by treatment with a provisional 1-stent versus planned 2-stent technique, and if so, whether such differences are conditioned by the complexity of the LM bifurcation lesion. Methods and Results: The clinical and angiographic characteristics, procedural methods and outcomes, and clinical events through 3-year follow-up were compared in patients undergoing distal LM PCI with a 1-stent provisional versus planned 2-stent technique in the EXCEL trial (Evaluation of XIENCE Versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization). Among 529 patients undergoing planned distal LM PCI, 344 (65.0%) and 185 (35.0%) were treated with intended 1-stent provisional and planned 2-stent techniques, respectively. The primary composite end point rate of death, myocardial infarction, or stroke at 3 years was significantly lower in patients treated with the provisional 1-stent versus planned 2-stent method (14.1% versus 20.7%; adjusted hazard ratio, 0.55; 95% CI, 0.35–0.88; P =0.01), driven by differences in cardiovascular death (3.3% versus 8.3%, P =0.01) and myocardial infarction (7.7% versus 12.8%, P =0.06). The 3-year rate of ischemia-driven revascularization of the LM complex was also lower in the provisional group (7.2% versus 16.3%, P =0.001). In 342 patients with distal LM bifurcation disease that did not involve both major side branch vessels, the 3-year primary end point was lower with a provisional 1-stent versus planned 2-stent technique (13.8% versus 23.3%, P =0.04), whereas no significant difference was present in 182 patients with distal LM bifurcation disease that did involve both side branch vessels (14.3% versus 19.2%, P =0.36). Conclusions: Among patients with distal LM bifurcation disease in the EXCEL trial randomized to PCI, 3-year adverse outcomes were worse with planned 2-stent treatment compared with a provisional 1-stent approach, a difference that was confined to patients without major involvement of both LM side branch vessels. Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT01205776.