Functional Assessment-guided Angioplasty in Patients With Coronary Chronic Total Occlusion

Study Overview
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Brief Summary
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The aim of this study is to investigate the role of functional evaluation for predicting clinical outcome in patients with coronary chronic total occlusion (CTO) undergoing percutaneous coronary intervention (PCI), and to evaluate the clinical evidence for the using of fractional flow reserve (FFR), coronary flow reserve (CFR), index of myocardial resistance (IMR) and dynamic single photon emission computed tomography (D-SPECT) in these patients.

Detailed Description
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PCI for CTO has dramatically changed in recent years. Although, with the improvement of devices and refinement of operator techniques, PCI of CTO can currently be performed with high success and low complication rates at experienced centers, the clinical benefit of recanalization of CTO is still a matter of debate. Accumulating evidence suggests that the improvement of left ventricular functional and prognosis is closely related with the area of viable myocardium, which has the potential for contractile recovery after revascularization. For the majority of interventional cardiologists, coronary angiography is the only invasive test deemed necessary for clinical decision-making, despite its weak ability to predict the functional impact of vascular occlusion on the subtended myocardium. To overcome this limitation, adjunctive diagnostic tools for functional evaluation, such as FFR, CFR, IMR and D-SPECT, have been introduced. In non-CTO patients, physiology-guided revascularization strategy has been definitely proven to be better than angiography-guided strategy in pivotal landmark studies. However, the clinical value of these functional parameters for the PCI of CTO is still unknown. The aim of this study was to determine whether functional evaluation is a better predictor of clinical outcome in patients with CTO undergoing PCI.

Official Title
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Functional Assessment-guided Angioplasty in Patients With Coronary Chronic Total Occlusion (FAGA-CTO)

Conditions
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Coronary Occlusion, Angioplasty, Balloon, Coronary

Intervention / Treatment
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* Procedure: percutaneous coronary intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 18 and ≤80 Patients diagnosed with CTO by coronary angiography Patient planned to receive PCI Diameter of CTO vessel > 2.25 mm Exclusion Criteria: Age >80 or <18 Myocardial infarction with 1 months Inability to give informed consent

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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

| Intervention/Treatment |
| --- |
|Procedure: percutaneous coronary intervention|PCI was performed using standard techniques. Antiplatelet and antithrombotic agents were prescribed according to current PCI guidelines. A procedure was considered successful when achieving TIMI flow grade 3 with <30% angiographic residual stenosis in the CTO vessel. All patients received drug-eluting stents and were discharged on dual antiplatelet therapy with duration of at least on year.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from Baseline FFR at 6 months after CTO PCI | FFR measurement in donor vessels at were performed simultaneously using pressure wires (Abbot) before attempting the CTO vessel. FFR measurement in the CTO vessels were performed after the wire arrived at the distal true lumen through antegrade or retrograde route. The FFR in donor and CTO vessels were measured again after successful stenting of CTO vessels. | At baseline and 6 months after CTO PCI | 
| Change from Baseline FFR at 6 months after CTO PCI | CFR measurement in donor vessels at were performed simultaneously using pressure wires (Abbot) before attempting the CTO vessel. CFR measurement in the CTO vessels were performed after the wire arrived at the distal true lumen through antegrade or retrograde route. The CFR in donor and CTO vessels were measured again after successful stenting of CTO vessels. | At baseline and 6 months after CTO PCI | 
| Change from Baseline Myocardial perfusion at 6 months after CTO PCI | The myocardial perfusion before and after CTO PCI was evaluated by dynamic SPECT. | At baseline and 6 months after CTO PCI | 
| Change from Baseline Myocardial Viability at 6 months after CTO PCI | The myocardial viability before and after CTO PCI was evaluated by PET-MRI. | At baseline and 6 months after CTO PCI | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| MACE | A major adverse cardiac event (MACE) was defined as the occurrence of cardiac death, nonfatal MI, and target lesion revascularization during the follow-up period. | 6 months after CTO PCI | 
| In-stent restenosis | In-stent restenosis was defined as >50% diameter stenosis by quantitative coronary angiography within a previously stented CTO vessel segment. | 6 months after CTO PCI | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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coronary chronic total occlusion, functional evaluation