Left Anterior Descending Nonculprit Lesions and Clinical Outcomes in Patients With ST-Segment Elevation Myocardial Infarction.

Background: In the COMPLETE (Complete vs Culprit-Only Revascularization to Treat Multi-Vessel Disease After Early PCI for STEMI) trial, complete revascularization in patients with ST-segment elevation myocardial infarction (STEMI) and multivessel disease (MVD) reduced important outcomes compared with culprit-only percutaneous coronary intervention. Whether clinical outcomes in STEMI patients with MVD are influenced by the presence of a left anterior descending (LAD) nonculprit lesion (NCL) remains unknown.

Objectives: This study sought to compare: 1) cardiovascular outcomes among patients with an NCL in the proximal/mid-LAD to patients with an NCL in other locations; and 2) the benefit of NCL revascularization in patients with and without a proximal/mid-LAD NCL.

Methods: The COMPLETE trial enrolled patients presenting with STEMI and MVD to angiography-guided complete revascularization vs a culprit lesion-only strategy. All coronary angiograms were evaluated in a central core laboratory. In this prespecified subanalysis, treatment effect according to proximal/mid-NCL location was determined for the coprimary outcomes of: 1) cardiovascular death or new myocardial infarction; and 2) cardiovascular death, new myocardial infarction, or ischemia-driven revascularization. Cox proportional hazards models were performed with an interaction term for treatment allocation and NCL location.

Results: Of the 4,041 subjects in COMPLETE, 1,666 patients had a proximal/mid-LAD NCL (41.2%). The first coprimary outcome occurred in 8.5% (2.9%/y) of patients with a proximal/mid-LAD NCL vs 9.9% (3.4%/y) in those without (adjusted HR: 0.83; 95% CI: 0.67-1.03). Complete revascularization had a similar benefit in reducing the first coprimary outcome for patients with a proximal/mid-LAD NCL (7.7% vs 9.2%; HR: 0.85; 95% CI: 0.61-1.18) and those without (8.0% vs 11.9%; HR: 0.65; 95% CI: 0.50-0.86), with no differential treatment effect (interaction P = 0.235) CONCLUSIONS: Among patients presenting with STEMI and multivessel CAD, those with a proximal/mid-LAD NCL had similar event rates to those without. The benefit of complete revascularization between the groups was similar, with no evidence of heterogeneity.