Impact of Acute Coronary Syndrome Classification and Procedural Technique on Clinical Outcomes in Patients With Coronary Bifurcation Lesions Treated With Drug‐Eluting Stents

Background: We examined the impact of non–ST‐segment elevation acute coronary syndrome (NSTE‐ACS) on clinical outcomes in patients with bifurcation lesions treated with drug‐eluting stents. Hypothesis: We hypothesized that NSTE‐ACS would be attributable to the increased risk of major adverse cardiac events (MACE) in bifurcation percutaneous coronary intervention. Methods: We enrolled 1668 patients, using data from a multicenter real‐world bifurcation registry. The primary objective was to compare the 2‐year cumulative risk of MACE in patients with NSTE‐ACS to those with stable angina. Major adverse cardiac events were defined as the composite endpoint of cardiac death, myocardial infarction (MI), and target‐lesion revascularization. Results: Non–ST‐segment elevation acute coronary syndrome was seen in 969 (58.1%) patients and stable angina in 699. Major adverse cardiac events occurred in 7.3% of NSTE‐ACS patients and in 5.2% with stable angina (P = 0.042). However, cardiac death, MI, and target‐lesion revascularization were similar between the 2 groups. We stratified patients with NSTE‐ACS into those with non–ST‐segment elevation MI and those with unstable angina. Cumulative risks of 2‐year MACEs were 7.0% in non–ST‐segment elevation MI patients and 7.5% in unstable angina patients (P = 0.87). In the NSTE‐ACS cohort, the baseline lesion length in the side branch (adjusted hazard ratio [HR]: 1.04, 95% confidence interval [CI]: 1.01‐1.07, P = 0.022), paclitaxel‐eluting stents in the main vessel (adjusted HR: 2.02, 95% CI: 1.21‐3.40, P = 0.008), and final kissing ballooning (adjusted HR: 1.88, 95% CI: 1.10‐3.21, P = 0.021) were independent predictors of MACE. Conclusions: Compared with stable angina patients, the NSTE‐ACS patients who underwent bifurcation percutaneous coronary intervention had an increased risk of MACE during the 2‐year follow‐up. Clin. Cardiol. 2012 doi: 10.1002/clc.22020 Drs Pil Sang Song and Dong Ryeol Ryu contributed equally to this work. Coronary Bifurcation Stenting (COBIS) Registry in South Korea, US Department of Health and Human Services, US National Institutes of Health, ClinicalTrials.gov no. NCT00851526. This work was supported by the Korean Society of Interventional Cardiology, Seoul, South Korea. The authors have no other funding, financial relationships, or conflicts of interest to disclose.