Short versus Long Duration Dual Antiplatelet Therapy after Drug-Eluting Stent for Coronary Chronic Total Occlusion Lesions

Abstract

BACKGROUND The optimal duration of dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) in patients with chronic total lesion (CTO) is still controversial. METHODS From Feb 2003 to May 2015, consecutive patients who underwent CTO-PCI with drug-eluting stents in Asan medical center were analyzed. The primary outcome was a major cardiovascular adverse event (MACE, composite of death, myocardial infarction, stent thrombosis, target vessel revascularization). Propensity-score matching with a 1:3 ratio was used for between-group comparison. RESULTS A total of 1119 CTO patients treated with drug-eluting stents was evaluated. Among excluding 169 patients who were followed up for less than 2 years, a total of 950 patients were included in the analysis. DAPT was used for 6 months or less and more than 6 months in 83 patients and 867 patients, respectively. In the matched cohort, the 5-year risk of MACE for long DAPT, as compared with the short DAPT, was not significantly different (hazard ratio [HR] 0.68, 95% confidence interval [CI]: 0.41-1.13; P=0.14). Similarly, there were no significant differences in the risk of death (HR 0.64, 95% CI, 0.27-1.50, P=0.31], myocardial infarction (HR:0.82, 95% CI 0.49-1.37, p=0.45), and target vessel revascularization (HR: 0.67, 95% CI 0.35-1.28 P=0.23). However, the risk of stent thrombosis was significantly higher with shorter DAPT (HR: 0.06, 95% CI 0.01-0.55, P=0.01). CONCLUSION After CTO-PCI with drug-eluting stents, there was no significant difference in major clinical outcomes between short and long DAPT. However, long DAPT strategy may be preferred considering the increased risk of stent thrombosis.