Nomogram to Predict Successful Septal Collateral Crossing during Percutaneous Coronary Intervention of Chronic Total Occlusion by retrograde approach: The Sep-CTO score

Septal collaterals are the main collaterals used in retrograde chronic total occlusion (CTO) percutaneous coronary intervention (PCI). However, there is little evidence regarding the selection of an interventional septal collateral (SC). we aimed to identify the predictors of successful guidewire crossing using clinical and anatomical characteristics. Overall, 216 derivation cases and 86 validation cases that included retrograde CTO PCI were analyzed. The technical success rate was 79.1% and there were no significant differences in the Gensini score, SYNTAX score, J-CTO score and Progress Score between two groups. Multivariate logistic regression analysis revealed that diabetes, small size, corkscrew, and side branch at tortuosity were independent factors of success in crossing SCs. We developed a nomogram to predict the success rate, which demonstrates favorable calibration and formed the Sep-CTO score. The calibration and decision curve analysis also demonstrated the reliability and accuracy of this clinical prediction model. The receiver-operating characteristic area of the nomogram was 0.870. Compared to the aforementioned scoring systems, Sep-CTO score was the most powerful. The nomogram may be a useful clinical tool. We found four independent variables to predict the successful guidewire crossing in septal collaterals.