Efficacy of Subintimal vs Intraluminal Approach for Atherosclerotic Chronic Occlusive Femoropopliteal Arterial Disease

Study Overview
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Brief Summary
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There are two ways of approaching atherosclerotic chronic occlusive femoro-popliteal arterial lesion with guide wire. One is the intraluminal approach of passing guide wire through the atheroma, the other is the subintimal approach of passing wire through the subintima of the vessel. Either of these two interventional technique can be chosen depending on the character of the lesions they have their own pros and cons which affects the success of the intervention. The study is limited to retrospective studies to which interventional technique is better for post-procedural recurrence rate, however there is no prospective randomized controlled study.

Detailed Description
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During interventions for atherosclerotic femoro-popliteal arterial lesion, chronic occlusive lesions are commonly encountered. The decision to approach these lesions by either guide wire, intraluminal approach or subintimal approach is by the decision of the operator. The subintimal approach intentionally passes the guide wire through the subintimal layer of vessel which was developed by Dr. Bolia. Through the subintimal approach, the success rate of procedure has increased. However this technique has shown some limitations which are guide wire re-entry, intimal injury, lengthening of the original lesion, periadventitial hematoma, perforated vessel, collateral vascular occlusion and limited usage of atherectomy devices. On the contrary, intimal approach is not only able to overcome the limitations of the subintimal approach, but it has shown an advantage in improving the success rate of the procedure by the variable techniques of anterograde, retrograde and trans-collaterals approach. These techniques however usually require longer procedure time with more exposure to larger amounts of intravenous contrast and radiation. It often cause the need for more interventional devices which results in higher expense such that it is a less cost-effective method. Recently the recommendation is the combination of these 2 interventional techniques depending on the character of lesions. As above, these approaches are chosen depending on the character of the lesion, however there are only limited retrospective studies without prospective randomized controlled study present to decide which method is better in terms of post-procedural recurrence rate.

Official Title
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Safety and Efficacy of Subintimal Versus Intraluminal Approach for Atherosclerotic Chronic Occlusive Femoro-Popliteal Arterial Disease: Prospective, Multicenter, Randomized, Controlled Trial (SCENARIO-FP)

Conditions
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Peripheral Arterial Disease, Atherosclerosis

Intervention / Treatment
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* Procedure: Intentional intraluminal approach
* Procedure: Intentional subintimal approach


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Clinical Criteria Age 20 years of older Symptomatic peripheral-artery disease with (Rutherford 2 - 6); moderate to severe claudication (Rutherford 2-3), chronic critical limb ischemia with pain while at rest (Rutherford 4), or with ischemic ulcers (Rutherford 5-6) Patients with signed informed consent Anatomical Criteria Chronic occlusive lesion in coronary angiography Stenosis of <50% atherosclerotic lesion of the ipsilateral femoropopliteal artery Residual stenosis of <50% atherosclerotic lesion of the ipsilateral femoro-popliteal artery after treatment for >50% of the lesion. Patent (≤50% stenosis) ipsilateral iliac artery or concomitantly treatable ipsilateral iliac lesions (≤30% residual stenosis), At least one patent (less than 50% stenosed) tibioperoneal run-off vessel. Only balloon angioplasty can be performed for popliteal arterial lesion, however if suboptimal or bailout result is expected with sole balloon angioplasty, stent placement is allowed. Bailout or suboptimal result is defined as SFA lesion. Exclusion Criteria: Under 20 years-old or over 85 years-old. Disagree with written informed consent Major bleeding history within prior 2 months Known hypersensitivity or contraindication to any of the following medications: heparin, aspirin, clopidogrel, cilostazol, or contrast agent Acute limb ischemia Previous bypass surgery or stenting of the ipsilateral femoro-popliteal artery Untreated inflow disease of the ipsilateral pelvic arteries (more than 50% stenosis or occlusion) Patients with major amputation (above the ankle amputation) which has been done, is planned or required Patients with life expectancy <1 year due to comorbidity Severe medical or surgical illness limit participating study.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Intentional intraluminal approach<br>Intentional intraluminal approach is the way that the passage of guidewire in chronic total occlusive femoro-popliteal arterial lesion is performed via intraluminal route using various intraluminal devices. in an intraluminal approach, the response to the balloon is more favorable, but the outcome depends on the experience of the surgeon, and the approach requires more time and is more costly. | Procedure: Intentional intraluminal approach<br>* Interventionist performs intentional intraluminal approach to angioplasty. Dedicated 018 and 014 guidewire for Chronic Total Occlusion (CTO) lesion and Chronic Total Occlusion (CTO) devices such as Truepath or Frontrunner can be chosen by interventionist. Methods to confirm successful intraluminal wiring will be selected, as follows; 1) examination for guidewire position in different two angles on fluoroscopy or 2) intravascular ultrasound (IVUS) exam after predilation is performed with an appropriately sized angioplasty balloon. After the guidewire is passed through the lumen of target lesion, predilation of the target lesion with an optimally sized balloon will be performed prior to stent implantation. Provisional stenting should be performed, if the case that optimal ballooning response is not obtained.<br>|
| Active Comparator: Intentional subintimal approach<br>Intentional subintimal approach is the method that recanalization is performed via subintimal route with a 0.035-inch looped guidewire and a supporting catheter at the occlusion site. Due to its simplicity and low cost, this approach has been used for many patients with femoropopliteal occlusion. | Procedure: Intentional subintimal approach<br>* Interventionist performs Intentional subintimal approach to angioplasty. 035 Terumo guidewires will be used. If 035 Terumo guidewire is not able to re-entry, Re-entry devices such as Offroad or OUTBACK catheter can be used. After the guidewire is passed through the subintimal layer of target lesion, predilation of the target lesion with an optimally sized balloon will be performed prior to stent implantation. Provisional stenting should be performed; the case that optimal ballooning response is not obtained should be enrolled. The sub-optimal balloon response is defined as a residual pressure gradient of >15 mmHg, residual stenosis of >30%, and flow-limiting dissection.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The rate of binary restenosis. | the rate of binary restenosis (stenosis of at least 50 percent of the luminal diameter) or PSVR ≥ 2.5 or zero (PSVR=peak systolic velocity within the area of stenosis divided by peak systolic velocity in a normal adjacent proximal artery segment) in the treated segment at 12 months after intervention as determined by catheter angiography or Duplex ultrasound. | One year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Limb salvage rate free of above-the-ankle amputation. |  | One year | 
| Sustained clinical improvement rate. |  | One year | 
| Repeated target lesion revascularization (TLR) rate. |  | One year | 
| Repeated target extremity revascularization (TER) rate. |  | One year | 
| Total reocclusion rate. |  | One year | 
| Comparison of late angiographic restenosis (%). |  | One year | 
| Ankle-brachial index (ABI). |  | One year | 
| The rate of major adverse cardiovascular events (MACE) composed of all-cause death, myocardial infarction and stroke. |  | One year | 
| The duration of the procedure from just before the guidewire enters the lesion, to when it proceeds into the distal normal vessel |  | One year | 
| The amount of contrast from just before the guidewire enters the lesion, to when it proceeds into the distal normal vessel |  | One year | 
| The length of distal normal vessel's injury related to the guidewire or re-entry device. |  | One year | 
| Incidence of vascular perforation with the failure rate of procedure. |  | One year | 
| Death rate related to procedure. |  | One year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Peripheral arterial disease, Atherosclerosis, Intraluminal approach, Subintimal approach