title: Clinical Prediction Score for Successful Retrograde Procedure in Chronic Total Occlusion Percutaneous Coronary Intervention.
abstract: OBJECTIVE
  To develop and validate a prediction score for a successful retrograde procedure in chronic total occlusion (CTO) percutaneous coronary intervention (PCI).
  
  
  METHODS
  A total of 228 CTO lesions in 223 patients who underwent PCI by retrograde approach were analyzed. All subjects were randomly grouped to a derivation set and a validation set at a ratio of 2:1. A successful retrograde procedure was set as the end point. Each of the identified predictors for the end point by logistic regression was assigned 1 point and summed.
  
  
  RESULTS
  Independent predictors of a successful retrograde procedure were Werner's score [odds ratio (OR) 4.841, 95% confidence interval (CI) 1.952-12.005, p = 0.001], diameter of distal CTO segment (OR 5.263, 95% CI 2.067-13.398, p < 0.001) and tortuous collateral (type b; OR 0.119, 95% CI 0.032-0.444, p = 0.002). The predictive model developed in the derivation set stratified the difficulty of achieving a successful retrograde procedure into 4 grades - very difficult (10.5%), difficult (23.7%), intermediate (50.7%) and easy (15.1%) - and was demonstrated significantly in the validation set: very difficult (15.8%), difficult (18.4%), intermediate (47.4%) and easy (18.4%). The area under the receiver-operating characteristic curve was 0.832 ± 0.042 for the derivation set and 0.912 ± 0.041 for the validation set with an almost equal performance.
  
  
  CONCLUSIONS
  According to the experience of our center, this model performed excellently in predicting the difficulty in achieving a successful retrograde procedure.
authors.affiliation: 2nd Section of the Cardiology Department, Guangdong Cardiovascular Institute, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.
authors.forename: Wei-Lu
authors.initials: WL
authors.lastname: Chai
authors.forename: Francis
authors.initials: F
authors.lastname: Agyekum
authors.forename: Bin
authors.initials: B
authors.lastname: Zhang
authors.forename: Hong-Tao
authors.initials: HT
authors.lastname: Liao
authors.forename: Dun-Liang
authors.initials: DL
authors.lastname: Ma
authors.forename: Zhi-An
authors.initials: ZA
authors.lastname: Zhong
authors.forename: Pei-Ning
authors.initials: PN
authors.lastname: Wang
authors.forename: Li-Jun
authors.initials: LJ
authors.lastname: Jin
mesh_terms: D000368:Aged; D002908:Chronic Disease; D054059:Coronary Occlusion / Q000175:diagnosis / Q000209:etiology / Q000601:surgery*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D062645:Percutaneous Coronary Intervention; D012372:ROC Curve; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome