Effectiveness of Repetitive Hyperbaric Oxygen Therapy for Chronic Limb-Threatening Ischemia.

BACKGROUND: Lower extremity artery disease is strongly associated with morbidity and is typically addressed through revascularization interventions. We assessed the clinical outcomes of patients with chronic limb-threatening ischemia (CLTI) without revascularization who did and did not undergo repetitive hyperbaric oxygen therapy (HBOT). METHODS: Between April 2002 and March 2017, the records of 58 patients with CLTI (Rutherford classification 4 in 19% and 5 in 81%) were evaluated retrospectively. HBOT was performed at 2.8 atm of oxygen (HBOT group). The control group included those who could not continue HBOT and historical controls. Patients in poor general health or with an indication for revascularization therapy were excluded. We examined major adverse events (MAEs) and limb salvage rates. Independent predictors and risk stratification were analyzed using a multivariate regression analysis. RESULTS: The mean age was 71±13 years. Of all patients, 67% had diabetes and 43% were undergoing hemodialysis. The mean follow-up period was 4.3±0.8 years. The overall survival rate was 84.5% and 81.0% at 1 and 3 years, respectively. The Cox regression analysis indicated that high body mass index (odds ratio [OR]: 0.86; 95% confidence interval [CI]: 0.76-0.97; p=0.01), well-nourished (OR: 1.21; 95% CI: 1.01-1.45), and HBOT (OR: 0.05; 95% CI: 0.01-0.26; p<0.001) independently predicted absence of MAEs. For major limb amputation, the ankle-brachial index (OR: 0.2; 95% CI: 0.05-0.86; p=0.03) and HBOT (OR: 0.04; 95% CI: 0.004-0.32; p=0.003) were independent predictors. CONCLUSIONS: Repetitive, stand-alone HBOT was associated with MAE-free survival and limb salvage in patients with CLTI.

A vein bypass first versus a best endovascular treatment first revascularisation strategy for patients with chronic limb threatening ischaemia who required an infra-popliteal, with or without an additional more proximal infra-inguinal revascularisation procedure to restore limb perfusion (BASIL-2): an open-label, randomised, multicentre, phase 3 trial.

BACKGROUND: Chronic limb-threatening ischaemia is the severest manifestation of peripheral arterial disease and presents with ischaemic pain at rest or tissue loss (ulceration, gangrene, or both), or both. We compared the effectiveness of a vein bypass first with a best endovascular treatment first revascularisation strategy in terms of preventing major amputation and death in patients with chronic limb threatening ischaemia who required an infra-popliteal, with or without an additional more proximal infra-inguinal, revascularisation procedure to restore limb perfusion. METHODS: Bypass versus Angioplasty for Severe Ischaemia of the Leg (BASIL)-2 was an open-label, pragmatic, multicentre, phase 3, randomised trial done at 41 vascular surgery units in the UK (n=39), Sweden (n=1), and Denmark (n=1). Eligible patients were those who presented to hospital-based vascular surgery units with chronic limb-threatening ischaemia due to atherosclerotic disease and who required an infra-popliteal, with or without an additional more proximal infra-inguinal, revascularisation procedure to restore limb perfusion. Participants were randomly assigned (1:1) to receive either vein bypass (vein bypass group) or best endovascular treatment (best endovascular treatment group) as their first revascularisation procedure through a secure online randomisation system. Participants were excluded if they had ischaemic pain or tissue loss considered not to be primarily due to atherosclerotic peripheral artery disease. Most vein bypasses used the great saphenous vein and originated from the common or superficial femoral arteries. Most endovascular interventions comprised plain balloon angioplasty with selective use of plain or drug eluting stents. Participants were followed up for a minimum of 2 years. Data were collected locally at participating centres. In England, Wales, and Sweden, centralised databases were used to collect information on amputations and deaths. Data were analysed centrally at the Birmingham Clinical Trials Unit. The primary outcome was amputation-free survival defined as time to first major (above the ankle) amputation or death from any cause measured in the intention-to-treat population. Safety was assessed by monitoring serious adverse events up to 30-days after first revascularisation. The trial is registered with the ISRCTN registry, ISRCTN27728689. FINDINGS: Between July 22, 2014, and Nov 30, 2020, 345 participants (65 [19%] women and 280 [81%] men; median age 72·5 years [62·7-79·3]) with chronic limb-threatening ischaemia were enrolled in the trial and randomly assigned: 172 (50%) to the vein bypass group and 173 (50%) to the best endovascular treatment group. Major amputation or death occurred in 108 (63%) of 172 patients in the vein bypass group and 92 (53%) of 173 patients in the best endovascular treatment group (adjusted hazard ratio [HR] 1·35 [95% CI 1·02-1·80]; p=0·037). 91 (53%) of 172 patients in the vein bypass group and 77 (45%) of 173 patients in the best endovascular treatment group died (adjusted HR 1·37 [95% CI 1·00-1·87]). In both groups the most common causes of morbidity and death, including that occurring within 30 days of their first revascularisation, were cardiovascular (61 deaths in the vein bypass group and 49 in the best endovascular treatment group) and respiratory events (25 deaths in the vein bypass group and 23 in the best endovascular treatment group; number of cardiovascular and respiratory deaths were not mutually exclusive). INTERPRETATION: In the BASIL-2 trial, a best endovascular treatment first revascularisation strategy was associated with a better amputation-free survival, which was largely driven by fewer deaths in the best endovascular treatment group. These data suggest that more patients with chronic limb-threatening ischaemia who required an infra-popliteal, with or without an additional more proximal infra-inguinal, revascularisation procedure to restore limb perfusion should be considered for a best endovascular treatment first revascularisation strategy. FUNDING: UK National Institute of Health Research Health Technology Programme.

Skeletal Muscle Bioenergetics in Critical Limb Ischemia and Diabetes.

INTRODUCTION: Mitochondrial dysfunction is implicated in the metabolic myopathy accompanying peripheral artery disease (PAD) and critical limb ischemia (CLI). Type-2 diabetes mellitus (T2DM) is a major risk factor for PAD development and progression to CLI and may also independently be related to mitochondrial dysfunction. We set out to determine the effect of T2DM in the relationship between CLI and muscle mitochondrial respiratory capacity and coupling control. METHODS: We studied CLI patients undergoing revascularization procedures or amputation, and non-CLI patients with or without T2DM of similar age. Mitochondrial respiratory capacity and function were determined in lower limb permeabilized myofibers by high-resolution respirometry. RESULTS: Fourteen CLI patients (65 ± 10y) were stratified into CLI patients with (n = 8) or without (n = 6) T2DM and were compared to non-CLI patients with (n = 18; 69 ± 5y) or without (n = 19; 71 ± 6y) T2DM. Presence of CLI but not T2DM had a marked impact on all mitochondrial respiratory states in skeletal muscle, adjusted for the effects of sex. Leak respiration (State 2, P < 0.025 and State 4o, P < 0.01), phosphorylating respiration (P < 0.001), and maximal respiration in the uncoupled state (P < 0.001), were all suppressed in CLI patients, independent of T2DM. T2DM had no significant effect on mitochondrial respiratory capacity and function in adults without CLI. CONCLUSIONS: Skeletal muscle mitochondrial respiratory capacity was blunted by ∼35% in patients with CLI. T2DM was not associated with muscle oxidative capacity and did not moderate the relationship between muscle mitochondrial respiratory capacity and CLI.

Measuring Quality of Life in Chronic Limb-threatening Ischemia Patients and Informal Carers: A Scoping Review.

OBJECTIVE: To review quality of life (QOL) instruments for chronic limb-threatening ischemia (CLTI) patients and informal carers, and their use in QOL and cost-utility analysis (CUA) studies. BACKGROUND: CLTI is a global health problem with significant morbidity affecting patients and informal carers. QOL is increasingly measured for holistic outcomes assessment and CUA. However, measurement instruments in CLTI are poorly understood. METHODS: MEDLINE, EMBASE, PsycINFO, CINAHL, COSMIN, PROQOLID, CEA registry, and NHS EED databases were searched for all English language studies up to May 2021. Features of instruments, evidence of measurement property appraisal, and trends in use were assessed. Prospective protocol registration (Open Science Framework: https://doi.org/10.17605/OSF.IO/KNG9U ). RESULTS: A total of 146 studies on QOL instruments (n=43), QOL outcomes (n=97), and CUA (n=9) were included. Four disease-specific QOL instruments are available for lower extremity arterial disease (intermittent claudication or CLTI). VascuQoL-25 and VascuQoL-6 have been used in CLTI. There is no CLTI-specific instrument. Of 14 generic instruments, SF-36, EQ-5D-3L, NHP, and WHOQOL-BREF were most common. Studies reporting partial measurement property appraisal favored VascuQoL-25, VascuQoL-6, and SF-36. Feasibility considerations include mode of administration and responder burden. None of 4 available carer-specific instruments have been used in CLTI. Since 1992, the number of QOL studies has increased considerably, but CUA studies are scarce. Informal carers have not been assessed. CONCLUSIONS: This review provides a comprehensive reference for QOL measurement in CLTI that helps end-users with instrument selection, use, and interpretation. However, a CLTI-specific instrument is needed. There is an opportunity to benefit society through future CUA studies and evaluation of QOL in informal carers.

Therapeutic angiogenesis for patients with no-option critical limb ischemia by adipose-derived regenerative cells: TACT-ADRC multicenter trial.

BACKGROUND: Patients with critical limb ischemia (CLI) still have a high rate of lower limb amputation, which is associated with not only a decrease in quality of life but also poor life prognosis. Implantation of adipose-derived regenerative cells (ADRCs) has an angiogenic potential for patients with limb ischemia. OBJECTIVES: We investigated safety, feasibility, and efficacy of therapeutic angiogenesis by cell transplantation (TACT) of ADRCs for those patients in multicenter clinical trial in Japan. METHODS: The TACT-ADRC multicenter trial is a prospective, interventional, open-labeled study. Patients with CLI (Fontaine class III-IV) who have no other option for standard revascularization therapy were enrolled in this study. Thirty-four target ischemic limbs of 29 patients were received freshly isolated autologous ADRCs implantation. RESULTS: The overall survival rate at a post-operative period and at 6 months follow-up was 100% at any time points. As a primary endpoint for efficacy evaluation, 32 limbs out of 34 (94.1%) were free from major amputation for 6 months. Numerical rating scale (from 6 to 1) as QOL score, ulcer size (from 317 mm2 at to 109 mm2), and 6-min walking distance (from 255 to 369 m) improved in 90.6%, 83.3%, and 72.2% patients, respectively. CONCLUSIONS: Implantation of autologous ADRCs could be safe and effective for the achievement of therapeutic angiogenesis in the multicenter settings, as a result in no major adverse event, optimal survival rate, and limb salvage for patients with no-conventional option against critical limb ischemia. TRN: jRCTb040190118; Date: Nov. 24th, 2015.

Sirolimus-Coated Balloon Angioplasty of Infra-popliteal Lesions for the Treatment of Chronic Limb-Threatening Ischemia: Study Protocol for the Randomized Controlled LIMES Study.

PURPOSE: Evidence on efficacy and long-term safety of paclitaxel-coated devices is still conflicting. Therefore, this study aims to assess whether sirolimus-coated balloon angioplasty is safe and effective for the treatment of infra-popliteal occlusions in patients with chronic limb-threatening ischemia (CLTI). STUDY DESIGN: The randomized controlled, single-blinded, multicentre, investigator-initiated study aims to enrol 230 participants with CLTI and infra-popliteal occlusions at up to 25 centres. Patients will be randomized in a 1:1 ratio to either sirolimus-coated balloon angioplasty or to plain old balloon angioplasty (POBA). Bailout stenting in case of flow-limiting dissection or ≥ 50% residual diameter stenosis is permitted. OUTCOME MEASURES: Primary outcome is the Kaplan-Meier estimate of primary patency at 6 months, defined as the absence of target lesion occlusion with restoration of in-line flow to the ankle. Key secondary outcome is non-inferiority in the proportionate occurrence of major adverse limb events and perioperative all-cause death at 30 days. Overall, participants will be followed for 36 months to assess further secondary efficacy and safety outcomes. ASSUMED GAIN OF KNOWLEDGE: If sirolimus-coated balloon angioplasty turns out to be superior to uncoated-balloon angioplasty regarding patency of infra-popliteal lesions without safety signals, it could become a welcome treatment option for patients with CLTI. Trial Registration ClinicalTrial.gov Identifier: NCT04772300, German Clinical Trials Register: DRKS00024629. Level of Evidence Level 2a, randomized controlled trial.

Twelve-Month Clinical Outcomes of Percutaneous Deep Venous Arterialization with Alternative Techniques and Ordinary Endovascular Therapy Devices for Patients with Chronic Limb-Threatening Ischemia: Results of the DEPARTURE Japan Study.

PURPOSE: A dedicated treatment strategy is not yet established for patients with no-option chronic limb-threatening ischemia. This study aimed to evaluate the clinical outcomes of percutaneous deep venous arterialization in Japanese patients with no-option chronic limb-threatening ischemia. MATERIALS AND METHODS: Data of 18 consecutive patients with chronic limb-threatening ischemia (18 limbs; mean age: 75.5 ± 8.5 years; 14 men) who underwent percutaneous deep venous arterialization between January 2016 and November 2020 were retrospectively reviewed. The limb salvage, amputation-free survival, and wound healing rates were evaluated using the Kaplan-Meier method. RESULTS: Among 18 patients, 14 (77.8%) had diabetes, 6 (33.3%) had a non-ambulatory status, 16 (88.9%) received hemodialysis, and 15 (83.3%) had wound, ischemia, and foot infection of clinical stage 4. Rutherford 5 was observed in 33.7% of the patients and Rutherford 6 in 66.7%. The technical success rate of percutaneous deep venous arterialization was 88.9%. Four patients required major amputation within 30 days; percutaneous deep venous arterialization failed in two of these patients. At 6 and 12 months, the limb salvage rates, amputation-free survival rates, and complete wound healing rates were 72.2 and 72.2%, 55.6 and 49.4%, and 23.0 and 53.2%, respectively. The median time to complete wound healing was 234 (interquartile range, 127-306) days. CONCLUSION: This study presented the clinical outcomes of patients with chronic limb-threatening ischemia who underwent percutaneous deep venous arterialization in Japan. Acceptable, safe, and efficacious results were reported. Before major amputation, percutaneous deep venous arterialization can be considered for patients with no-option chronic limb-threatening ischemia. LEVEL OF EVIDENCE: Level 3. Non-randomized, follow-up study.

Impact of Serum Zinc Level and Oral Zinc Supplementation on Clinical Outcomes in Patients Undergoing Infrainguinal Bypass for Chronic Limb-Threatening Ischemia.

BACKGROUND: Zinc (Zn) has been reported to play an important role in wound healing (WH). Nevertheless, the effect of Zn in chronic limb-threatening ischemia (CLTI) patients is unclear. This study investigated the effect of Zn on the clinical outcomes of CLTI patients undergoing bypass surgery.Methods and Results: This study reviewed 111 consecutive patients who underwent an infrainguinal bypass from 2012 to 2020. Patients with Zn deficiency (serum Zn level <60 µg/dL) received oral Zn supplementation and maintained a normal level until WH. This study aimed to explore: (1) the effect of Zn deficiency; and (2) Zn supplementation in Zn-deficient patients on the clinical outcomes of this cohort. Patients with Zn deficiency, Zn supplementation, and no Zn supplementation despite Zn deficiency accounted for 48, 21, and 42 patients, respectively. (1) Zn deficiency was associated with WH (HR, 0.47; 95% CI, 0.29-0.78: P=0.003), major adverse limb events (MALE) (HR, 2.53; 95% CI, 1.26-5.09: P=0.009), and major amputation or death (HR, 3.17; 95% CI, 1.51-6.63: P=0.002). (2) Zn supplementation was positively related to WH (HR, 2.30; 95% CI, 1.21-4.34: P=0.011). This result was confirmed using propensity score matching (HR, 2.24; 95% CI, 1.02-4.87: P=0.043). CONCLUSIONS: The current study revealed that Zn level was associated with clinical outcomes in CLTI patients after bypass surgery. Oral Zn supplementation could improve WH in these patients.

Astragaloside IV promotes the angiogenic capacity of adipose-derived mesenchymal stem cells in a hindlimb ischemia model by FAK phosphorylation via CXCR2.

BACKGROUND: Therapeutic angiogenesis by transplantation of autologous/allogeneic adipose stem cells (ADSCs) is a potential method for the treatment of critical limb ischemia (CLI). However, the therapeutic efficiency is limited by poor viability, adhesion, migration and differentiation after cell transplantation into the target area. Astragaloside IV (AS-IV), one of the main active components of Astragalus, has been widely used in the treatment of ischemic diseases and can promote cell proliferation and angiogenesis. However, there is no report on the effect of AS-IV on ADSCs and its effect on hindlimb ischemia through cell transplantation. PURPOSE: The purpose of this study was to elucidate that AS-IV pretreatment enhances the therapeutic effect of ADSC on critical limb ischemia, and to characterize the underlying molecular mechanisms. METHODS: ADSCs were obtained and pretreated with the different concentration of AS-IV. In vitro, we analyzed the influence of AS-IV on ADSC proliferation, migration, angiogenesis and recruitment of human umbilical vein endothelial cells (HUVECs) and analyzed the relevant molecular mechanism. In vivo, we injected drug-pretreated ADSCs into a Matrigel or hindlimb ischemia model and evaluated the therapeutic effect by the laser Doppler perfusion index, immunofluorescence, and histopathology. RESULTS: In vitro experiments showed that AS-IV improved ADSC migration, angiogenesis and endothelial recruitment. The molecular mechanism may be related to the upregulation of CXC receptor 2 (CXCR2) to promote the phosphorylation of focal adhesion kinase (FAK). In vivo, Matrigel plug assay showed that ADSCs pretreated with AS-IV have stronger angiogenic potential. The laser Doppler perfusion index of the hindlimbs of mice in the ADSC/AS-IV group was significantly higher than the laser Doppler perfusion index of the hindlimbs of mice of the ADSC group and the control group, and the microvessel density was significantly increased. CONCLUSION: Our results demonstrate that AS-IV pretreatment of ADSC improves their therapeutic efficacy in ameliorating severe limb exclusion symptomology through CXCR2 induced FAK phosphorylation, which will bring new insights into the treatment of severe limb ischemia.

Impact of Longer Hemodialysis Vintage with Higher Serum Phosphorus Level on Clinical Outcomes in Patients with Chronic Limb-Threatening Ischemia Presenting Tissue Loss after Endovascular Therapy.

AIMS: Hemodialysis vintage and serum phosphorus levels adversely affect outcomes in patients on hemodialysis. Whether these factors have a similar prognostic impact on patients who are on hemodialysis and have chronic limb-threatening ischemia (CLTI) has not been systematically studied. We aimed to explore the risk factors, including hemodialysis vintage and serum phosphorus levels, on clinical outcomes after endovascular therapy (EVT) in hemodialysis patients with CLTI. METHODS: The current study rerospectively analyzed 374 hemodialysis patients with CLTI presenting with ischemic tissue loss (age: 72.3±9.0 years, male: 73.3%, diabetes mellitus: 68.2%, Rutherford 5: 75.9%, 6: 24.1%, WIfI stage 4: 50.0%) primarily treated with EVT between April 2007 and December 2016. The primary outcome measure was 1-year amputation-free survival (AFS), while the secondary outcome measure was 1-year wound healing. Predictors for each outcome were evaluated by Cox proportional hazards model. RESULTS: Multivariate analysis significantly associated longer hemodialysis vintages with higher serum phosphorus levels (hazard ratio [HR], 0.599; 95% confidence interval [CI], 0.394-0.910; p=0.016) with 1-year AFS. Longer vintages for hemodialysis with higher serum phosphorus levels were marginally, but not significantly, associated with 1-year wound healing. (HR, 0.684; 95% CI, 0.467-1.000; p=0.050). CONCLUSION: Longer hemodialysis vintages with higher serum phosphorus levels adversely affect outcomes after EVT for hemodialysis patients with CLTI presenting with ischemic tissue loss.

Multi-Level Lower Extremity Arterial Revascularization Via Retrograde Pedal Access Under Local Anesthesia in a Patient With Severe Cardiopulmonary Comorbidities: A Case Report.

BACKGROUND: Chronic limb-threatening ischemia is a severe form of peripheral artery disease that leads to high rates of amputation and mortality if left untreated. Bypass surgery and antegrade endovascular revascularization through femoral artery access from either side are accepted as conventional treatment modalities for critical limb ischemia. The retrograde pedal access revascularization is an alternative treatment modality useful in specific clinical scenarios; however, these indications have not been well described in literature. This case report highlights the use of retrograde pedal access approach as primary treatment modality in a patient with an extensive comorbidities precluding general anesthesia nor supine positioning. CASE PRESENTATION: The patient is a 60-year-old female with multiple severe cardiopulmonary comorbidities presenting with dry gangrene of the right great toe. Her comorbidities and inability to tolerate supine positioning precluded her from receiving open surgery, general anesthesia or monitored sedation, or percutaneous femoral access. Rather, the patient underwent ankle block and retrograde endovascular revascularization via dorsalis pedis artery access without post-operative complications. DISCUSSION: The prevalence of comorbidities related to peripheral artery disease is increasing and with it the number of patients who are not optimal candidates for conventional treatment methods for critical limb ischemia. The retrograde pedal access revascularization as initial treatment modality offers these patients an alternative limb salvaging treatment option.

Impact of Controlling a Nutritional Status Score on Wound Healing in Patients with Chronic Limb-Threatening Ischemia after Endovascular Treatment.

BACKGROUND: Chronic limb-threatening ischemia (CLTI) is the most advanced stage of peripheral artery disease. Therefore, a multidisciplinary approach is necessary to avoid major amputation in CLTI patients. Malnutrition worsens the condition of CLTI patients, and therefore, it may be important to evaluate the nutritional status in patients with CLTI. This study was designed to evaluate the baseline patient characteristics and the influence of the controlling nutritional status (CONUT) score on the clinical results. METHOD AND RESULTS: A retrospective, single-center, non-randomized study was conducted to evaluate the associations of death, major amputation, and wound healing rate at 12 months with the CONUT score on admission. Consecutive CLTI patients (mean age 73.2 ± 10.4 years; 84 males) who underwent endovascular therapy (EVT) for infra-popliteal lesions at Fukuoka University Hospital from January 2014 to May 2019 were enrolled and divided into two groups (higher and lower CONUT score groups). The higher CONUT group showed a higher percentage of dialysis (66.7% vs. 33.9%, p < 0.001) and a higher clinical frailty scale (5.9 ± 1.4 vs. 4.9 ± 1.9, p = 0.005) than the lower CONUT group. Rates of amputation-free survival were 89.5% and 69.8% in the lower and higher CONUT groups, respectively. In addition, rates of wound healing at 12 months were 98.0% and 78.3% in the lower and higher CONUT groups, respectively. Multivariate regression analysis demonstrated that a higher CONUT score was an independent predictor for delayed wound healing (OR: 11.2; 95% CI: 1.29-97.5; p = 0.028). CONCLUSION: An assessment of the nutritional status using the CONUT score could be useful for predicting wound healing, and earlier nutritional intervention may improve the outcome of CLTI patients. Early examination and treatment, along with raising awareness of the issue, may be important for improving the prognosis.

Classificação WifI: o novo sistema de classificação da Society for Vascular Surgery para membros inferiores ameaçados, uma revisão de literatura / WIfI classification: the Society for Vascular Surgery lower extremity threatened limb classification system, a literature review

Resumo A Society for Vascular Surgery propôs nova classificação para o membro inferior ameaçado, baseada nos três principais fatores influenciadores do risco de amputação do membro: ferida (Wound, W), isquemia (Ischemia, I) e infecção do pé (foot Infection, fI): a classificação WIfI. Esta abrange também os diabéticos, anteriormente excluídos do conceito de isquemia crítica do membro devido a seu quadro clínico complexo. O objetivo da classificação era fornecer estratificação de risco precisa e precoce ao paciente com membro inferior ameaçado; auxiliar no manejo clínico, permitindo comparar terapias alternativas; e predizer o risco de amputação em 1 ano e a necessidade de revascularização. O objetivo deste estudo é reunir os principais pontos abordados sobre a classificação WIfI no meio científico. A maior parte dos estudos de validação da classificação demonstram sua associação à predição de salvamento do membro, eventos de reintervenção, amputação e estenose, taxas de amputação maior e menor, sobrevida livre de amputação, e cicatrização de feridas.

Abstract The Society for Vascular Surgery has proposed a new classification system for the threatened lower limb, based on the three main factors that have an impact on limb amputation risk: Wound (W), Ischemia (I) and foot Infection ("fI") - the WIfI classification. The system also covers diabetic patients, previously excluded from the concept of critical limb ischemia because of their complex clinical condition. The classification's purpose is to provide accurate and early risk stratification for patients with threatened lower limbs; assisting with clinical management, enabling comparison of alternative therapies; and predicting risk of amputation at 1 year and the need for limb revascularization. The objective of this study is to collect together the main points about the WIfI classification that have been discussed in the scientific literature. Most of the studies conducted for validation of this classification system prove its association with factors related to limb salvage, such as amputation rates, amputation-free survival, prediction of reintervention, amputation, and stenosis (RAS) events, and wound healing.