Foot Perfusion Analysis to Predict Limb Salvage

Study Overview
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Brief Summary
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This study aims at evaluating the correlation between foot perfusion on angiographies performed before and after revascularization and limb salvage in patients with critical limb ischemia.

Detailed Description
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Critical limb ischemia (CLI) in diabetic patients is increasing drastically worldwide, and is already recognized as a major health issue. CLI is frequently leading to major amputations. Therefore, one of the key point to prevent limb loss is to restore a good vascularization to the foot, usually thanks to endovascular means. No consensual indicator is currently available to estimate if the limb revascularization will be sufficient or not to prevent amputation, and to help physicians decide if they should be more aggressive during the endovascular procedure. Transcutaneous oximetry and value of the ankle-brachial index (ABI) are commonly used in the ward (not available in the operating room), but have shown poor correlation to wound healing or limb salvage and results are frequently biased because of the arterial wall calcifications due to diabetes. Value of the first toe systolic pressure is currently under evaluation to predict survival without amputation, with promising results, but cannot be applied to patients with wounds at this level or previous minor amputation. The emergence of hybrid rooms in the operating theater offer access to high quality imaging and image post-treatment. Those capabilities could be used to analyze the flow and the tissue perfusion in the foot, and correlate those imaging parameters to positive clinical outcomes, such as wound healing, thus creating a useful tool to guide physicians in daily practice. Differences between foot angiographies performed before and after revascularization could be used to estimate the quality of the revascularization and predict wound healing and limb salvage. This method would be directly available in the operating room and could help physicians to optimize their strategy during the procedure

Official Title
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Perfusion Analysis of the Foot in Patients With Critical Limb Ischemia Before and After Revascularization and Predictive Value on Amputation-free Survival

Conditions
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Critical Limb Ischemia, Peripheral Arterial Disease

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with critical limb ischemia Rutherford 4, 5 and 6, with at least one pre-operative exam (CTA, magnetic resonance angiography or ultrasound) demonstrating a peripheral arterial disease, and requiring an endovascular or hybrid (meaning combined with a surgical technique) revascularization of the lower limb. Exclusion Criteria: Patients not willing to give their consent to study enrollment Patients under 18 years old Patients with severe renal insufficiency (estimated creatinine clearance < 30 mL/min), without dialysis Patients with life threatening septic wounds who would require an amputation at the initial presentation

Ages Eligible for Study
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Minimum Age: 18 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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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of participants with major amputation | Major amputations are defined as below or above the knee amputations on the treated limb. This is a clinical binary criterion (0=Freedom from major amputation, 1=Major amputation) | 1 month | 
| Number of participants with major amputation | Major amputations are defined as below or above the knee amputations on the treated limb. This is a clinical binary criterion (0=Freedom from major amputation, 1=Major amputation) | 3 months | 
| Number of participants with major amputation | Major amputations are defined as below or above the knee amputations on the treated limb. This is a clinical binary criterion (0=Freedom from major amputation, 1=Major amputation) | 6 months | 
| Number of participants with major amputation | Major amputations are defined as below or above the knee amputations on the treated limb. This is a clinical binary criterion (0=Freedom from major amputation, 1=Major amputation) | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Wound Healing | Complete wound Healing at the level of the foot according to the WiFI classification | 1 month | 
| Wound Healing | Complete wound Healing at the level of the foot according to the WiFI classification | 3 months | 
| Wound Healing | Complete wound Healing at the level of the foot according to the WiFI classification | 6 months | 
| Wound Healing | Complete wound Healing at the level of the foot according to the WiFI classification | 1 year | 
| Number of patients with secondary intervention | Number of participants with a secondary intervention. Secondary intervention is defined as all secondary surgical interventions (both endovascular and open repairs) associated to critical limb ischemia on the same limb. It includes secondary angioplasties, bypasses or minor and major amputations. This is a clinical binary criterion (0= Freedom from secondary intervention, 1=At least one secondary intervention) | 1 year | 
| Overall Mortality | Overall Mortality, all-cause included | 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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limb salvage, foot perfusion, hybrid room