Impact of smoking status on clinical outcomes after successful chronic total occlusion intervention: Korean national registry of CTO intervention

Objectives We sought to evaluate the effect of cigarette smoking on long-term outcomes after successful percutaneous coronary intervention for chronic total occlusion (CTO) lesions. Background Cigarette smoking promotes the progression of atherosclerosis but enhances the antiplatelet effect of clopidogrel. Methods The Korea National Registry of CTO Intervention included 2,167 patients with CTO lesions from 26 centers who were successfully revascularized with drug-eluting stents from 2007 to 2009. Thrombotic events were defined as the composite of cardiac death, nonfatal myocardial infarction, and stent thrombosis. Results Current-smokers had more favorable baseline characteristics such as a younger age and lower prevalence of hypertension and diabetes mellitus. At 1 year, current-smokers had a significantly lower thrombotic event rate (1.1% vs. 2.7%, P = 0.034), but a significantly higher target vessel revascularization (TVR) rate (7.2% vs. 4.2%, P = 0.017) compared with never-smokers. After adjustment, current-smoking was independently associated with a 72% decreased risk for thrombotic events, and 73% increased risk for TVR. Conclusions In patients with a revascularized CTO lesion, cigarette smoking is associated with fewer thrombotic events but with a higher incidence of TVR. Patients with CTO may benefit from smoking cessation to reduce TVR in conjunction with the use of new more potent antiplatelet agents whose effect is independent of cigarette smoking to improve thrombotic events.