Optimal Duration for Dual Antiplatelet Therapy After Left Main Coronary Artery Stenting

Background: Coronary interventions using drug-eluting stents (DESs) of left main coronary artery (LMCA) lesions have shown favorable clinical outcomes. However, duration of dual antiplatelet therapy (DAPT) after LMCA interventions has not yet been investigated. Methods and Results: From a multicenter Korean Multicenter Angioplasty Team (KOMATE) registry, 1,004 patients who received DES implantations for LMCA lesions and did not experience major adverse cardiovascular events (including major bleeding) for 1 year after coronary intervention were analyzed. Patients were divided into 2 groups; DAPT <= 12 (n=503) and >12 months (n=501). The primary endpoint was number of net clinical adverse events (NACEs), composite of cardiac deaths, myocardial infarctions, stent thrombosis and major bleeding events. During a 4.5-year follow-up period after LMCA interventions, the DAPT >12 months group showed a lower NACE rate than the DAPT <= 12 months group (adjusted-HR 0.53 [0.29-0.99], P=0.045). For patients who maintained DAPT >12 months, rate of cardiac deaths, myocardial infarctions, and stent thrombosis events were lower than in patients who had DAPT <= 12 months (adjusted-HR 0.35 [0.17-0.73], P=0.005) without increased major bleeding (P=0.402). Conclusions: For patients who can continue DAPT without major bleeding events, prolonged DAPT (>12 months) after LMCA stenting demonstrated better long-term efficacy outcomes than DAPT <= 12 months with comparable safety.