title: Validation of the J-chronic total occlusion score for chronic total occlusion percutaneous coronary intervention in an independent contemporary cohort.
abstract: BACKGROUND
  Chronic total occlusion (CTO) recanalization is a complex and technically challenging procedure. The J-CTO score has been proposed to stratify case complexity and procedural success rates. However, the score has never been tested outside the setting of the original study. Moreover, its predictive value when using a hybrid antegrade or retrograde approach is unknown. We investigated the performance of the J-CTO score for predicting procedure complexity and success in an independent contemporary cohort.
  
  
  RESULTS
  A total of 209 consecutive patients who underwent CTO recanalization by a high-volume operator were included. Clinical and angiographic data were prospectively collected. The J-CTO score was applied for each patient, and discrimination and calibration were evaluated in the whole cohort, and according to the approach (antegrade 47% and retrograde 53%). Clinical and angiographic differences were noted between the original and studied cohort. The mean J-CTO score was 2.18±1.26, and successful guidewire crossing within 30 minutes and final angiographic success were 44.5% and 90.4%, respectively. The J-CTO score demonstrated good discrimination (c statistic, >0.70) and calibration (Hosmer-Lemeshow P>0.1) in the whole cohort and for antegrade and retrograde approaches. However, the final success rate was not associated with the J-CTO score.
  
  
  CONCLUSIONS
  In this independent cohort, the J-CTO score showed good discriminatory and calibration capacity for guidewire CTO crossing within 30 minutes but it does not for final success rate. The J-CTO score helps to predict complexity of CTO recanalization, and the simplicity of the score supports the widespread use as a clinical tool.
authors.affiliation: From the Multidisciplinary Department of Cardiology, Institut Universitaire de Cardiologie et de Pneumologie de Québec (Quebec Heart & Lung Institute), Laval University, Quebec City, Quebec, Canada.
authors.forename: Luis
authors.initials: L
authors.lastname: Nombela-Franco
authors.forename: Marina
authors.initials: M
authors.lastname: Urena
authors.forename: Miguel
authors.initials: M
authors.lastname: Jerez-Valero
authors.forename: Can Manh
authors.initials: CM
authors.lastname: Nguyen
authors.forename: Henrique Barbosa
authors.initials: HB
authors.lastname: Ribeiro
authors.forename: Yoann
authors.initials: Y
authors.lastname: Bataille
authors.forename: Josep
authors.initials: J
authors.lastname: Rodés-Cabau
authors.forename: Stéphane
authors.initials: S
authors.lastname: Rinfret
mesh_terms: D000368:Aged; D002908:Chronic Disease; D015331:Cohort Studies; D054059:Coronary Occlusion / Q000628:therapy*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D062645:Percutaneous Coronary Intervention; D012042:Registries; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D016896:Treatment Outcome
keywords: chronic disease; coronary occlusion; percutaneous coronary intervention