Risk Factors and Outcomes in Coronary Chronic Total Occlusion

Study Overview
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Brief Summary
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This study aims to assess the risk factors and evaluate the long-term outcomes of patients with coronary chronic total occlusion (CTO) treated with percutaneous coronary intervention or medical treatment.

Detailed Description
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Coronary artery disease (CAD) is still one of the major contributors to global mortality. CTO is a special lesion type of CAD, defined as complete occlusion of at least one major epicardial coronary artery more than 3 months. Compared to non-CTO patients, those with CTO have worse prognosis. The prognosis of CTO patients is related to many factors including the baseline characteristics, modality of treatment and the degree of coronary collateral formation. Figuring out the factors which can indicate the outcomes of CTO is essential to clinical decision making. In this single center, observational study, we collect patient's clinical characteristics and blood samples to investigate potential factors associated with the development of coronary collateral formation and outcomes in patents with stable coronary artery disease.

Official Title
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Risk Factors and Outcomes in Patients With Stable Coronary Artery Disease and Coronary Chronic Total Occlusion

Conditions
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Chronic Total Occlusion, Coronary Artery Disease

Intervention / Treatment
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* Procedure: Coronary angiography


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥18 years; Patients with angina or silent ischemia and documented ischemia; Patients with CTO ≥ 3months Exclusion Criteria: eGFR<15mL/(min·1.73m2); Chronic heart failure with NYHA grade ≥3; Had a history of coronary artery bypass grafting; Had received a percutaneous coronary intervention within the prior 3 months; Malignant tumor or immune system disorders; Pulmonary heart disease

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients with good coronary collaterals<br>Coronary collateral circulation development was graded according to the Rentrop score, grade 2 (partial filling of the epicardial segment by collateral vessels); grade 3 (complete filling of the epicardial artery by collateral vessels) were defined as good coronary collateral circulation. | Procedure: Coronary angiography<br> <br> |
| Patients with poor coronary collaterals<br>Coronary collateral circulation development was graded according to the Rentrop score, grade 0 (no filling of any collateral vessels) and grade 1 (filling of side branches of the artery to be perfused by collateral vessels without visualization of the epicardial segment) were defined as poor coronary collateral circulation. | Procedure: Coronary angiography<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The degree of collateral estimated visually by Rentrop score during coronary angiography |  | Immediate post-angiography | 
| Composite event of all-cause mortality, non-fatal myocardial infarction, heart failure and repeat revascularization |  | up to 5 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Event of all-cause mortality |  | up to 5 years | 
| Event of death from cardiac causes |  | up to 5 years | 
| Event of heart failure |  | up to 5 years | 
| The change of left ventricular ejection fraction |  | 1 year | 
| Events of repeat revascularization |  | up to 5 years | 
| Event rate of procedural success |  | Immediate post-PCI | 
| Event of procedural outcomes |  | 1 month post-angiography or PCI |