Evaluation of Effectiveness and Safety of Antegrade and Retrograde Approach of Percutaneous Coronary Intervention for Chronic Total Occlusions

Study Overview
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Brief Summary
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Objective of this study is to 1) analyze the clinical, anatomical and periprocedural differences of patients who underwent a procedure related to coronary CTO through the antergrade approach and retrograde approach; 2) analyze the success rate of the procedures and the incidence and patterns of complications; 3) compare and analyze long-term performances after the successful procedure; and 4) identify the independent factors that require a retrograde approach and the prognostic factor regarding long-term performances after use of each approach.

Official Title
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Evaluation of Effectiveness and Safety of Antegrade and Retrograde Approach of Percutaneous Coronary Intervention for Chronic Total Occlusions; Systemic Chronic Total Occlusion Revascularization Korea Research-Chronic Total Occlusion (STRIKE-CTO) Study

Conditions
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Chronic Total Occlusion of Coronary Artery

Intervention / Treatment
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* Procedure: antegrade and retrograde approach


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients aged>=19 Patients who have a CTO lesion in at least one or more epicardial coronary artery 2.5 mm in blood vessel diameter Patients who have symptoms of angina or objectively proven myocardial ischemia (asymptomatic myocardial ischemia, stable or unstable angina, non - -ST-segment elevation myocardial infarction) Patients who voluntarily agreed to the protocol and the clinical follow-up plan (or let their representative do this), and signed the informed consent form approved by the IRB of each study institute Exclusion Criteria: Patients who are pregnant or lactating or have childbearing potential Patients in whom contrast medium and heparin are contraindicated or who are hypersensitive to them Patients in whom aspirin, clopidogrel, ticagrelor and prasugrel, cilostazol are contraindicated Patients scheduled to undergo a surgery, etc. that requires discontinuance of an antiplatelet drug within 12 months after participation in the study Acute ST elevation myocardial infarction at the time of hospitalization Terminally ill patients with their life expectancy < one year Patients who have serious diseases other than cardiac diseases that may affect limitation of residual life time or observation of the protocol (e.g. oxygen-independent chronic obstructive pulmonary disease, persisting hepatitis or serious hepatic insufficiency, severe renal disease, etc. Be left up to the discretion of the investigator.)

Ages Eligible for Study
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Minimum Age: 19 Years

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

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Observational<br> | Procedure: antegrade and retrograde approach<br>* This study intends to identify and compare the clinical, anatomical and periprocedural factors of the patients who used only the antergrade approach and the patients who needed the retrograde approach among the patients with coronary CTO<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Death | Death | 12-month after PCI | 
| myocardial infarction | the periprocedural myocardial infarction under the SCAI definition or the non-lethal myocardial infarction during the follow-up observations | 12-month after PCI | 
| the complex endpoints of target vessel revascularization/reocclusion occurrence | including chronic total occlusion and angiostenosis | 12-month after PCI | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Procedure success rate | A procedure success defined as the case where a final vessel diameter stenosis < 30% is achieved after the stent insertion | every 1-year up-to 5-year | 
| Myocardial infarction | Q-wave VS non-Q-wave, periprocedural myocardial infarction VS follow-up myocardial infarction (spontaneous myocardial infarction | every 1-year up-to 5-year |