Application of Coronary Artery Chronic Total Occlusion Scoring Systems

Study Overview
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Brief Summary
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Studying the prediction ability of different CTO scoring systems on Asian CTO PCI population with their relation to technical success and developing a newer stepwise approach depending on these CTO scoring systems for choosing the suggested successful approach considering collateral channel assessment.

Detailed Description
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Study of applying the Japenese CTO, Castle and Progress CTO scores on all coronary CTO PCI cohort done at national Taiwan university hospital (NTUH) Study tools: Basal demographic data collection( age, cardiovascular risk factors, patients clinical data, lesion characteristics, periprocedural complications). The Japanese Chronic Total Occlusion (J-CTO) score calculated for assessment of CTO procedures complexity and predict the likelihood of guide wire crossing within 30 min, as assembled by Morino et al. The J-CTO score is the sum of the following 5 binary parameters: blunt proximal cap, calcification, bending >45°, length of occluded segment >20 mm, and previously failed PCI attempt. Each of these independent variables was assigned a value of 1 when present. With increasing probability of difficulty of wire crossing from 0 as easy till 5 as very difficult. Also, the PROGRESS-CTO score calculated (reference website: https://www.progresscto.org/cto with evaluation of 4 baseline angiographic characteristics (proximal cap ambiguity, absence of retrograde collaterals, moderate or severe tortuosity, and LCX CTO) used to determine the likelihood of technical success with CTO PCI. Each of these independent variables was assigned a value of 1 when present. With increasing probability of difficulty of success from 0 as easy till 5 as very difficult. Euro CTO CASTLE scoring calculation The CASTLE (coronary artery bypass graft history, age, stump anatomy, tortuosity degree, length of occlusion, and extent of calcification) model applied retrospectively on the patients with every item taking 1 point if present And Technical failure rates range from 8% (CASTLE score 0 to 1) to 35% (CASTLE score ≥4). Collateral assessment including type (septal, epicardial or bypass grafts), size by Werner classification [is graded as: 0, no visible connection between the donor and the recipient coronary artery; 1, thread-like connection between the donor and the recipient coronary artery; 2, side-branch like connection between the donor and the recipient coronary artery], tortuosity degree as by the CC scoring system of the NTUH--> Channel tortuosity caculated as the presence of ≥2 high-frequency, successive curves (within 2 mm) in the context of epicardial collaterals and ≥1 high-frequency curve that failed to uncoil in diastole for septal channels (thus a measure of channel distensibility). A high-frequency curve is defined as a curve that is >180° occurring within a segment length <3× the diameter of the collateral. And all these scores references and calculation items are mentioned in the references below….

Official Title
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Application of Coronary Artery Chronic Total Occlusion (CTO) Scoring Systems Detecting Their Prediction Ability on CTO Percutaneous Coronary Intervention (PCI) Procedures

Conditions
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Chronic Total Occlusion of Coronary Artery

Intervention / Treatment
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* Procedure: percutaneous coronary intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All coronary CTO PCI procedures done at national Taiwan university hospital (NTUH) with their data available for analysis from 2015 till the study data collection step. Exclusion Criteria: Patients whom data not completed
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Procedure: percutaneous coronary intervention|doing percutaneous revascularization of chronic coronary total occlusion.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| comparison of the effecacy of using CTO scoring systems (J-CTO scoring, Castle Score and progress scoring along with the CC scoring in prediction of technical success. | comaprling the three CTO scores for all CTO PCI patients done by experienced operator ( J-CTO scoring, Castle Score and progress scoring ) for prediction of technical success with higher scores indicating higher probability of difficulty along with the CC scoring in predicting higher chances of technical success in retrograde CTO PCI patients. | Two months |