Comparison of Clinical Outcomes Between Incomplete and Complete Revascularization in NSTEMI Patients With Multivessel Disease

BACKGROUND: The optimal revascularization strategy for patients with non-ST-segment elevation myocardial infarction (NSTEMI) and multivessel disease remains controversial. OBJECTIVES: This study aimed to compare the 3-year clinical outcomes of incomplete revascularization (IR) vs complete revascularization (CR) in NSTEMI patients with multivessel disease. METHODS: Among 29,625 patients enrolled in the nationwide pooled registry of the KAMIR-NIH (Korea Acute Myocardial Infarction Registry-National Institutes of Health) and KAMIR-V, 6,987 NSTEMI patients with multivessel disease who underwent percutaneous coronary intervention were analyzed. CR was defined as residual stenosis <30% in all vessels ≥2.25 mm with TIMI flow grade 3. The primary endpoint was major adverse cardiac events at 3 years, a composite of all-cause death, recurrent myocardial infarction, unplanned repeat revascularization, and hospitalization for heart failure. RESULTS: Of 6,987 patients, 3,072 underwent CR and 3,915 IR. The majority of patients underwent percutaneous coronary intervention for non-infarct-related artery during index procedure (6,144 of 6,987; 88.0%). CR was associated with a lower 3-year risk of major adverse cardiac events compared with IR (18.6% vs 26.9%; adjusted HR: 0.75; 95% CI: 0.66-0.85; P < 0.001), driven by reductions in cardiac death or recurrent myocardial infarction (6.9% vs 10.4%; adjusted HR: 0.76; 95% CI: 0.60-0.95; P = 0.015) and unplanned repeat revascularization (8.6% vs 13.1%; adjusted HR: 0.68; 95% CI: 0.56-0.82; P < 0.001). Findings were consistent after adjustment using propensity score matching and inverse probability weighting. CONCLUSIONS: In NSTEMI patients with multivessel disease, CR was associated with significantly improved 3-year clinical outcomes compared with IR.