Background—: We developed a model that predicts difficulty of percutaneous coronary intervention for coronary chronic total occlusion (CTO) using coronary computed tomographic angiography. Methods and Results—: A total of 684 CTO lesions with preprocedural computed tomographic angiography were enrolled from 4 centers. Data were randomly divided into derivation and validation datasets at 2:1 ratio. The end point was successful guidewire crossing ≤30 minutes, which was met in 50%. The KCCT (Korean Multicenter CTO CT Registry) score was developed based on independent predictors identified by multivariable analysis, which were proximal blunt entry, proximal side branch, bending, occlusion length ≥15 mm, severe calcification, whole luminal calcification, reattempt, and ≥12 months or unknown duration of occlusion. The KCCT score was compared with the other prediction scores, including angiography-based J-CTO, PROGRESS-CTO, CL-score, and CT-based CT-RECTOR. The probability of guidewire crossing ≤30 minutes declined consistently from 100% to 0% according to the KCCT score ( P <0.01, all). The KCCT score showed higher discriminative performance compared with the other scoring systems (c-statistics=0.78 versus 0.65–0.72, P <0.001, all). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of a KCCT score of <4 for guidewire crossing ≤30 minutes was 70%, 68%, 72%, 73%, and 70%, respectively. The KCCT score also showed consistent results with procedural success ( P <0.05, all). These results could be reproduced in validation data set ( P <0.05, all). Conclusions—: KCCT scoring could predict successful guidewire crossing ≤30 minutes and also procedural success. KCCT scoring may enable noninvasive grading difficulty of CTO percutaneous coronary intervention.

Background—: The aim of this study was to assess whether deferred stenting (DS) reduces infarct size and microvascular obstruction (MVO) compared with immediate stenting (IS) in primary percutaneous coronary intervention for ST-segment–elevation myocardial infarction. Methods and Results—: From February 2013 to August 2015, 114 patients (mean age: 69 years) were randomized into the following 2 groups: DS with an intention to stent 3 to 7 days later or IS after primary reperfusion in 2 centers. The primary and secondary end points were infarct size and the incidence of MVO, respectively, assessed by cardiac magnetic resonance imaging at 30 days after primary reperfusion. The median time to the second procedure in the DS was 72.8 hours. Six patients in the DS group were crossed over to the IS group because of progression of dissection or safety concerns after randomization. In the intention-to-treat analysis, DS did not significantly reduce infarct size (15.0% versus 19.4%; P =0.112) and the incidence of MVO (42.6% versus 57.4%; P =0.196), compared with IS. However, in anterior wall myocardial infarction, infarct size (16.1% versus 22.7%; P =0.017) and the incidence of MVO (43.8% versus 70.3%; P =0.047) were significantly reduced in the DS group. There was no urgent revascularization event during deferral period. Conclusions—: A routine DS did not significantly reduce infarct size and MVO compared with IS, although it was safe. The beneficial effect of DS in patients with anterior myocardial infarction should be confirmed by larger randomized studies. Clinical Trial Registration—: URL: http://www.clinicaltrials.gov . Unique identifier: NCT02324348.

Background: There have been little data about outcomes of percutaneous coronary intervention (PCI) for in-stent restenosis (ISR) chronic total occlusion (CTO) in the drug eluting stent (DES) era. This study aimed to compare the procedural success rate and long-term clinical outcomes of ISR CTO and de novo CTO. Methods and results: Patients who underwent PCI for ISR CTO (n = 164) versus de novo CTO (n = 1208) were enrolled from three centers in Korea between January 2008 and December 2014. Among a total of ISR CTO, a proportion of DES ISR CTO was 79.3% (n = 130). The primary outcome was major adverse cardiac events (MACEs); a composite of all-cause death, non-fatal myocardial infarction (MI), or target lesion revascularization (TLR). Following propensity score-matching (1:3), the ISR CTO group (n = 156) had a higher success rate (84.6% vs. 76.0%, p = 0.035), mainly driven by high success rate of PCI for DES ISR CTO (88.6%), but showed a higher incidence of MACEs [hazard ratio (HR): 2.06; 95% confidence interval (CI) 1.37–3.09; p < 0.001], mainly driven by higher prevalence of MI [HR: 9.71; 95% CI 2.06–45.81; p = 0.004] and TLR [HR: 3.04; 95% CI 1.59–5.81; p = 0.001], during 5 years of follow-up after successful revascularization, as compared to the de novo CTO group (n = 408). Conclusion: The procedural success rate was higher in the ISR CTO than the de novo CTO, especially in DES ISR CTO. However, irrespective of successful revascularization, the long-term clinical outcomes for the ISR CTO were significantly worse than those for the de novo CTO, in terms of MI and TLR. Graphic

Yu CW, et al. Korean Circ J. 2016 Sep;48:e75. https://doi.org/10.4070/kcj.2018.0117

Background: The current guidelines recommend both repeat stenting and drug-coated balloons (DCB) for in-stent restenosis (ISR) lesions, if technically feasible. However, real-world clinical data on the interventional strategies in patients with left main bifurcation (LMB)-ISR have not been elucidated. Methods: Seventy-five patients with LMB-ISR, who underwent percutaneous coronary intervention (PCI) between January 2009 and July 2015, were retrospectively reviewed for the present study (repeat drug eluting stent [DES] implantation [n = 51], DCB angioplasty [n = 24]). Results: Analysis of the baseline characteristics showed that the patients in the DCB group had a lower incidence of non-ST segment elevation myocardial infarction/ST segment elevation myocardial infarction at the index PCI (8.3% vs. 25.5%; p = 0.12), higher low-density lipoprotein-cholesterol level (92.9 mg/dL vs. 81.7 mg/dL; p = 0.09), and more “stent-in-stent” lesions (25% vs. 7.8%; p = 0.07) than those in the DES group. A smaller post-procedural minimal target lesion lumen diameter was also noted in the DCB group than in the DES group (2.71 mm vs. 2.85 mm; p = 0.03). The cumulative incidence rates of major adverse cardiac events (MACEs) were similar between both groups (median follow-up duration, 868 days; MACE rate, 25% in the DCB group vs. 25.5% in the DES group; p = 0.96). The multivariate Cox regression analysis indicated that the true bifurcation of ISR was an independent risk predictor of MACEs (hazard ratio, 4.62; 95% confidence interval, 1.572–13.561; p < 0.01). Conclusions: DES and DCB showed comparable long-term clinical results in patients with LMB-ISR lesions.