Ungi, Imre

Background: Predicting technical failure in chronic total occlusion (CTO) percutaneous coronary intervention (PCI) can assist with decision making and planning of the procedure. Methods: We analyzed 6,946 CTO PCIs performed between 2016 and June 2022 at 36 international centers in the Prospective Global Registry for the Study of Chronic Total Occlusion Intervention (PROGRESS-CTO) and created a score for risk of technical failure. Logistic regression prediction modeling was used to identify independently associated variables with technical failure and model were internally validated with bootstrapping. Results: Mean patient age was 64.0±10 years, 82% were men and technical success was 86%. The following variables were independently associated with technical failure and were included in the final model: age (odds ratio [OR]: 1.08, 95% Confidence Intervals [CI]: [1.00-1.15], p=0.039; age≥ 65 years; 1 point), CTO length (OR: 1.13, 95% CI [1.10, 1.17]; length≥ 20 mm; 1 point), moderate/severe calcification (OR: 1.35, 95% CI [1.17, 1.56]; 1 point), proximal cap ambiguity (OR: 2.25, 95% CI [1.95, 2.59]; 2 points), lack of interventional collaterals (OR: 1.60, 95% CI [1.39, 1.84]; 1 point), and lack of good distal landing zone (OR: 1.51, 95% CI [1.31, 1.75]; 1 point). The resulting score showed acceptable performance on receiver-operating characteristic (ROC) curve, AUC: 0.68 (95% CI [0.67-0.71]). Internal validation with bootstrapping of 1000 samples demonstrated a good agreement with the model, observed AUC: 0.68, (95% bias corrected CI [0.67, 0.70]). PROGRESS-CTO technical failure score and corresponding risk percentage and the percentage of patients in the respective risk group within the PROGRESS-CTO registry are represented in Figure 1. Conclusion: The updated PROGRESS CTO score may be useful for assessing the likelihood of technical failure success in CTO PCI.