Outcomes of angiosome and non-angiosome targeted revascularization in critical lower limb ischemia

Comparative Outcomes of Targeted Versus Nontargeted Angiosome Revascularization for Diabetic Foot Wounds Impact of Target Arterial Path on Wound Healing

BACKGROUND

Diabetes is strongly correlated with the development of critical limb ischemia, with a predilection for below-the-knee and below-the-ankle patterns of arterial disease. The angiosome concept, described as a potential framework for targeted revascularization in critical limb ischemia, has generated divergent opinions over the last decades. This study aims to evaluate the implication of angiosome-targeted revascularization in wound healing in diabetic patients.

METHODS

This is a single-center retrospective study including diabetic patients with ischemic ulcers admitted for invasive vascular study and revascularization between January and December 2019. The primary outcome was to evaluate the impact of angiosome-targeted revascularization in wound healing. Limb-based patency and amputation-free survival according to Global Limb Anatomic Staging System stage and revascularization procedures were considered secondary outcomes.

RESULTS

Data from 117 limbs of 114 diabetic patients with neuroischemic diabetic foot were evaluated. There was no significant difference between targeted and nontargeted angiosome-revascularization in wound healing at 12 months. However, angiosome-targeted revascularization was associated with shorter healing times. The severity of the infection was the only variable with an impact on healing time. Endovascular surgery did not show inferior patency to open surgery, even in patients with more complex arterial disease (GLASS III).

CONCLUSIONS

Although angiosome-guided revascularization did not demonstrate significantly higher healing rates at 12 months, there appears to be a trend toward faster healing.

Influence of crural vessel run-off on short- and mid-term outcomes following femoro-popliteal bypass grafting

OBJECTIVES

To determine the influence that the number of patent crural run-off vessels has on short- and mid-term outcomes following femoro-popliteal bypass.

METHODS

All patients undergoing index femoro-popliteal bypass grafting between 2013 and 19 at our unit were included. Preoperative imaging was used to stratify patients into cohorts with either one or ≥2 patent run-off vessels. Primary outcomes measures included bypass patency and limb salvage rates at one and 3 years post-operatively. Survival analysis was performed using Kaplan-Meier curves and Logrank test.

RESULTS

147 bypasses performed on 143 patients were included. 24 patients had one-vessel run-off and 123 had ≥2 vessels patent. Patients with one-vessel run-off had a higher proportion of emergency admissions (54% vs 41%) and diabetes (42% vs 31%). 31% of patients underwent diagnostic angiogram imaging in addition to having duplex ultrasound and/or computed tomography angiography. There were no significant differences in primary, primary-assisted or secondary patency rates between the cohorts at 12 or 36 months. Limb salvage rates were significantly higher amongst those with ≥2 vessel run-off at 12 (86% vs 71%, p = 0.03) and 36 (85% vs 71%, p = 0.04) months. For those with occluded grafts, a higher proportion of patients with ≥2 vessel run-off subsequently had an attempt at redo bypass grafting.

CONCLUSIONS

Femoro-popliteal bypass is a reasonable treatment option for patients with one-vessel run-off. However, whilst patency rates are comparable, clinicians should be aware of the lower successful limb salvage rates for patients with one patent vessel (especially those presenting with tissue loss).

Outcomes for Patients With Chronic Limb-Threatening Ischemia After Direct and Indirect Endovascular and Surgical Revascularization: A Meta-Analysis and Systematic Review

PURPOSE

The purpose of this review and meta-analysis is to determine the clinical outcome differences between patients with chronic limb-threatening ischemia who underwent direct versus indirect angiosome revascularization using either the surgical or endovascular approach.

MATERIALS AND METHODS

The data sources used for article selection included PubMed, Embase/Medline, Cochrane reviews, and Web of Science (All studies were in English and included up to September 2023). All articles included were comparative in design, including retrospective, prospective, and randomized controlled trials that compared the clinical outcomes between direct and indirect angiosome-guided revascularization in chronic limb-threatening ischemia. A random-effects model was used to determine the measure of association between direct revascularization and amputation-free survival, wound healing, and overall survival. Publication bias was assessed with both Begg's and Egger's test, and heterogeneity was calculated using an I2.

RESULTS

Data from 9 articles were analyzed and reported in this review. Direct revascularization was associated with improved amputation-free survival (odds ratio [OR]=2.632, confidence interval [CI]: 1.625, 4.265), binary wound healing (OR=2.262, CI: 1.518, 3.372), and overall survival (OR=1.757, CI: 1.176, 2.625). Time until wound healed was not associated with either direct or indirect revascularization (Standard Mean Difference [SMD]=-2.15, p=0.11). There was a low risk of bias across all studies according to the RoB 2.0 tool.

CONCLUSION

Direct revascularization is associated with improved amputation-free survival, overall survival, and wound healing in chronic limb-threatening ischemic patients compared to the indirect approach.

CLINICAL IMPACT

Preservation of the lower extremity is critical for preventing mortality and maintaining independence. The benefit of angiosome-guided revascularization for chronic limb-threatening ischemia remains controversial. The authors of this article aim to review the current literature and compare direct and indirect angiosome-guided intervention for preserving the lower extremity. Current findings suggest direct angiosome-guided intervention reduces amputation rates and improves survival; however, many trials neglect to address the multifactorial approach needed in wound care management.

Effectiveness of revascularisation for the ulcerated foot in patients with diabetes and peripheral artery disease: A systematic review

INTRODUCTION

Peripheral artery disease (PAD) is associated with an increased likelihood of delayed or non-healing of a diabetes-related foot ulcer, gangrene, and amputation. The selection of the most effective surgical technique for revascularisation of the lower limb in this population is challenging and there is a lack of conclusive evidence to support the choice of intervention. This systematic review aimed to determine, in people with diabetes and tissue loss, if direct revascularisation is superior to indirect revascularisation and if endovascular revascularisation is superior to open revascularisation for the outcomes of wound healing, minor or major amputation, and adverse events including mortality.

METHODS

Title and abstract searches of Medline, Embase, PubMed, and EBSCO were conducted from 1980 to 30th November 2022. Cohort and case-control studies and randomised controlled trials reporting comparative outcomes of direct (angiosome) revascularisation (DR) and indirect revascularisation (IR) or the comparative outcomes of endovascular revascularisation and open or hybrid revascularisation for the outcomes of healing, minor amputation, and major amputation in people with diabetes, PAD and tissue loss (including foot ulcer and/or gangrene) were eligible. Methodological quality was assessed using the Cochrane risk-of-bias tool for randomised trials, the ROBINS-I tool for non-randomised studies, and Newcastle-Ottawa Scale for observational and cohort studies where details regarding the allocation to intervention groups were not provided.

RESULTS

From a total 7086 abstracts retrieved, 26 studies met the inclusion criteria for the comparison of direct angiosome revascularisation (DR) and indirect revascularisation (IR), and 11 studies met the inclusion criteria for the comparison of endovascular and open revascularisation. One study was included in both comparisons. Of the included studies, 35 were observational (31 retrospective and 4 prospective cohorts) and 1 was a randomised controlled trial. Cohort study quality was variable and generally low, with common sources of bias related to heterogeneous participant populations and interventions and lack of reporting of or adjusting for confounding factors. The randomised controlled trial had a low risk of bias. For studies of DR and IR, results were variable, and it is uncertain if one technique is superior to the other for healing, prevention of minor or major amputation, or mortality. However, the majority of studies reported that a greater proportion of participants receiving DR healed compared with IR, and that IR with collaterals may have similar outcomes to DR for wound healing. For patients with diabetes, infrainguinal PAD, and an adequate great saphenous vein available for use as a bypass conduit who were deemed suitable for either surgical procedure, an open revascularisation first approach was superior to endovascular therapy to prevent a major adverse limb event or death (Hazard Ratio: 0.72; 95% CI 0.61-0.86). For other studies of open and endovascular approaches, there was generally no difference in outcomes between the interventions.

CONCLUSIONS

The majority of available evidence for the effectiveness of DR and IR and open and endovascular revascularisation for wound healing and prevention of minor and major amputation and adverse events including mortality in people with diabetes, PAD and tissue loss is inconclusive, and the certainty of evidence is very low. Data from one high quality randomised controlled trial supports the use of open over endovascular revascularisation to prevent a major limb event and death in people with diabetes, infrainguinal disease and tissue loss who have an adequate great saphenous vein available and who are deemed suitable for either approach.

Angiosome-Targeted Infrapopliteal Angioplasty: Impact on Clinical Outcomes-An Observational Study

Background: Revascularization based on the angiosome concept (AC) is a controversial subject because there is currently no clear evidence of its efficacy, due to the heterogeneity of patients (multiple and diverse risk factors and comorbidities, multiple variations in the affected angiosomes). Choke vessels change the paradigm of the AC, and the presence or absence of the plantar arch directly affects the course of targeted revascularization. The aim of this study was to evaluate the effect of revascularization based on the AC in diabetic patients with chronic limb-threatening ischemia (CLTI). Methods: This retrospective analysis included 51 patients (40 men, 11 women), with a mean age of 69 years (66-72) and a total of 51 limbs, who presented with Rutherford 5-6 CLTI, before and after having undergone a drug-coated balloon angioplasty (8 patients) or plain balloon angioplasty (43). Between November 2018 and November 2019, all patients underwent below-the-knee balloon angioplasties and were followed up for an average of 12 months. The alteration of microcirculation was compared between directly and indirectly revascularized angiosomes. The study assessed clinical findings and patient outcomes, with follow-up investigations, comparing wound healing rates between the different revascularization methods. Patient records and periprocedural leg digital subtraction angiographies (DSA) were analyzed. Differences in outcomes after direct revascularization and indirect percutaneous transluminal angioplasty (PTa) were examined using Cox proportional hazards analysis, with the following endpoints: ulcer healing, limb salvage, and also amputation-free survival. Results: Direct blood flow to the angiosome supplying the ulcer area was achieved in 38 legs, in contrast to 13 legs with indirect revascularization. Among the cases, there were 39 lesions in the anterior tibial artery (ATA), 42 lesions in the posterior tibial artery (PTA), and 8 lesions in the peroneal artery (PA). According to a Cox proportional hazards analysis, having fewer than three (<3) affected angiosomes (HR 0.49, 95% CI 0.19-1.25, p = 0.136) was associated with improved wound healing. Conversely, wound healing outcomes were least favorable after indirect angioplasty (p = 0.206). When adjusting the Cox proportional hazard analysis for the number of affected angiosomes, it was found that direct drug-coated angioplasty resulted in the most favorable wound healing (p = 0.091). At the 1-year follow-up, the major amputation rate was 17.7%, and, according to a Cox proportional hazards analysis, atrial fibrillation (HR 0.85, 95% CI 0.42-1.69, p = 0.637), hemodialysis (HR 1.26, 95% CI 0.39-4.04, p = 0.699), and number of affected angiosomes > 3 (HR 0.94, 95% CI 0.63-1.39, p = 0.748) were significantly associated with poor leg salvage. Additionally, direct endovascular revascularization was associated with a lower rate of major amputation compared to indirect angioplasty (HR 1.09, 95% CI 0.34-3.50, p = 0.884). Conclusions: Observing the angiosomes concept in decision-making appears to result in improved rates of arterial ulcer healing and leg salvage, particularly in targeted drug-coated balloon angioplasty for diabetic critical limb ischemia, where multiple angiosomes are typically affected.

Success of transmetatarsal amputation for limb salvage in patients with peripheral artery disease

Limb salvage is a difficult path for patients to travel as there is no guarantee of the outcome, often the major factor is perfusion. For patients who underwent transmetatarsal amputation (TMA), success rate is crucial as the next option is most likely a major amputation. We performed a 10 years (2010-2020) retrospective review of patients that underwent a TMA and had an angiogram or computed tomography angiography (CTA) perioperatively at the Dallas VA Medical Center. Failure after TMA was defined as a patient requiring a proximal amputation within 1 year. There were 125 TMAs performed between 2010 and 2020 at the institution. Forty-four (35.2%) patients had an angiogram/CTA peri-operative and met the inclusion criteria. Seventeen subjects (38.6%) had a higher level of amputation. Of the 17 failures, 2 (11.8%) patients had no patent vessel runoff to the foot, 9 (52.9%) had one vessel, 4 (23.5%) had two vessels, and 2 (11.8%) had three vessels runoff. One vessel runoff to the foot yielded a high rate of poor outcomes (56.3%) defined as a higher level of amputation. Two or more vessels runoff to the foot had over 75% success of limb salvage with a TMA.

Chronic Limb-Threatening Ischemia in Patients with Type 2 Diabetes: Revascularization Index as a Predictor for Primary Endovascular Intervention Outcome

Purpose

Chronic limb-threatening ischemia in patients with diabetes is associated with a high risk of adverse outcomes. The associated co-morbidities, the heterogeneity of foot presentation and the distribution of atherosclerotic lesions led to the emergence of multiple revascularization strategies and scoring systems to improve management outcomes. This study aimed to introduce a new index, the revascularization index (RI), and to assess its predictive value for the outcomes of primary endovascular intervention in patients with type 2 diabetes presenting with chronic limb-threatening ischemia.

Patients and Methods

A retrospective electronic medical records review was conducted for patients with type 2 diabetes presenting with chronic limb-threatening ischemia managed at King Abdullah University Hospital by primary endovascular interventions between January 2014 and August 2019. The RI was analyzed for its predictive value for the treatment outcomes.

Results

A total of 187 patients were included in this study, with a major lower limb amputation rate of 19.3%. The performance of the RI was excellent in predicting secondary revascularization (AUC = 0.80, 95% CI: 0.73-0.86, p-value < 0.001), good to predict major amputation (AUC = 0.76, 95% CI: 0.67-0.85, p-value = 0.047), and poor in predicting death (AUC = 0.46, 95% CI: 0.40-0.55, p-value = 0.398). RI of <1.21 was significantly associated with a higher risk of major lower limb amputation (HR = 5.8, 95% CI: 1.25-26.97, p-value < 0.025), and RI of < 1.3 was associated with a higher risk for secondary revascularization.

Conclusion

The RI can be used to predict major adverse lower limb events (MALE). It might be used as a guide for the extent of endovascular interventions for diabetic chronic limb-threatening ischemia with multi-level outflow atherosclerotic disease.

Assessment of chronic limb threatening ischemia using thermal imaging

OBJECTIVES

Current chronic limb threatening ischemia (CLTI) diagnostics require expensive equipment, using ionizing radiation or contrast agents, or summative surrogate methods lacking in spatial information. Our aim is to develop and improve contactless, non-ionizing and cost-effective diagnostic methods for CLTI assessment with high spatial accuracy by utilizing dynamic thermal imaging and the angiosome concept.

APPROACH

Dynamic thermal imaging test protocol was suggested and implemented with a number of computational parameters. Pilot data was measured from 3 healthy young subjects, 4 peripheral artery disease (PAD) patients and 4 CLTI patients. The protocol consists of clinical reference measurements, including ankle- and toe-brachial indices (ABI, TBI), and a modified patient bed for hydrostatic and thermal modulation tests. The data was analyzed using bivariate correlation.

RESULTS

The thermal recovery time constant was on average higher for the PAD (88%) and CLTI (83%) groups with respect to the healthy young subjects. The contralateral symmetry was high for the healthy young group and low for the CLTI group. The recovery time constants showed high negative correlation to TBI (ρ = -0.73) and ABI (ρ = -0.60). The relation of these clinical parameters to the hydrostatic response and absolute temperatures (|ρ|<0.3) remained unclear.

CONCLUSION

The lack of correlation for absolute temperatures or their contralateral differences with the clinical status, ABI and TBI disputes their use in CLTI diagnostics. Thermal modulation tests tend to augment the signs of thermoregulation deficiencies and accordingly high correlations were found with all reference metrics. The method is promising for establishing the connection between impaired perfusion and thermography. The hydrostatic modulation test requires more research with stricter test conditions.

Choosing the appropriate catheter and wire in peripheral intervention

Endovascular treatment is becoming more common in managing patients with peripheral arterial disease. A carefully planned procedure is crucial for the outcome of the procedure. Several steps are necessary when performing endovascular procedures, including preplanning with vascular imaging using computed tomography angiography (CTA) or magnetic resonance angiography (MRA), choosing the right access and technique, and using the right devices (guidewires, sheaths, catheters). The length, diameter, stiffness, coating, and tip shape of the guidewire should be adjusted according to the initial information and preparation. A sheath is not always necessary but can be beneficial when several catheter changes are planned. There are three types of angiographic catheter (flush, exchange, and selective), each of which should be considered and used wisely according to its function. The guidewire, sheath, and catheter choices will follow from the initial information gathered, the access and technique chosen, and the availability of the devices.

Effectiveness of Sucrose Octasulfate Dressing in the Treatment of Neuro-Ischaemic Diabetic Foot Heel Ulcers: A Retrospective Single arm Study

The study aimed to evaluate the effectiveness of the use of sucrose octasulfate impregnated dressing (TLC-NOSF [Technology Lipido-Colloid-Nano-OligoSaccharide Factor]) in the management of persons with neuro-ischaemic heel diabetic foot ulcers (DFUs). Consecutive patients who referred for an active non-infected neuro-ischaemic heel DFU belonging to grade IC (superficial) or IIC (deep to tendons, muscle or capsule) according to Texas University Classification were included. All patients were managed by a pre-set limb salvage protocol in the respect of International guidelines and the TLC-NOSF dressing was used as primary and specific dressing. Patients were evaluated any 2 to 4 weeks until wound healing or different outcomes. Primary outcome was the rate of complete wound healing after 24 weeks of follow-up. The secondary outcomes assessed the healing time, the rate of wound regression, the re-ulceration in the case of complete healing and the safety. Thirty patients were included. The mean age was 67 ± 11 years, 17 (56.7%) were male, all of them were affected by type 2 diabetes with a mean duration of 18 ± 7 years. Twenty patients (66.7%) showed deep ulcers (grade 2 of Texas University Classification); the mean TcPO2 at the inclusion was 42 ± 7 mm Hg. Twenty-two patients (73.3%) healed by Week 24. The mean time of healing was 84 ± 32 days, 2 (6.7%) patients had ulcer relapse after healing, 28 (93.3%) had wound regression >50%, 2 (6.7%) had mild infection, 1 (3.3%) reported major amputation. No serious adverse events related to TLC-NOSF dressing or local reactions were reported. This current study showed the potential benefit of sucrose octasulfate for treating neuro-ischaemic heel DFUs in addition to the standard of care.

Validation of the correlation between angiosome-based target arterial path, mid-term limb-based patency, and the global limb anatomical staging system

This study aimed to validate the correlation between the Global Limb Anatomical Staging System (GLASS) and limb-based patency (LBP) and angiosome-based target arterial path (TAP) and to detect the predictors of LBP loss. After the publication of the Global Vascular Guidelines in 2019, the evaluation of GLASS and identification of TAP have been recommended. However, there are few reports regarding GLASS. Eighty-three patients with chronic limb-threatening ischemia (CLTI) and tissue loss from 2016 to 2020 were evaluated. The correlation between GLASS and LBP and successful revascularization of angiosome-based TAP was analyzed. We also investigated the predictors of LBP loss. The number of patients in each GLASS stage was as follows: GLASS I, 6 patients; GLASS II, 15 patients; GLASS III, 62 patients. At 6 months, the Kaplan-Meier estimate of LBP was 66.7% in GLASS I, 41.6% in GLASS II, and 16.4% in GLASS III, respectively (p = 0.034). The rate of successful revascularization of angiosome-based TAP was 100% in GLASS I, 86.7% in GLASS II, and 46.8% in GLASS III, respectively (p = 0.002). Multivariate analysis showed that the Wound, Ischemia, and foot Infection (WIfI) stage [hazard ratio (HR) 1.58; 95% confidence interval (CI) 1.07-2.33; p = 0.021] and GLASS infrapopliteal (IP) grade (HR 1.96; 95% CI 1.31-2.95; p = 0.001) were the independent predictors of LBP loss. The GLASS stage was significantly correlated with successful revascularization of angiosome-based TAP and mid-term LBP. The WIfI stage and GLASS IP grade were the independent predictors of loss of LBP.

Evaluation of Peripheral Perfusion in the Presence of Plantar Heel Ulcerations Status After Transmetatarsal Amputation With Achilles Tendon Lengthening

The objective of this study is to evaluate peripheral perfusion in patients who developed plantar heel ulcerations status after transmetatarsal amputation and Achilles tendon lengthening. Peripheral perfusion was assessed via contrast angiography of the 3 crural vessels (anterior tibial, posterior tibial, and peroneal arteries), as well as intact heel blush and plantar arch. The secondary objective is to correlate the arterial flow to time to develop heel ulceration and incidence of minor and major lower-extremity amputation. Diagnostic angiography without intervention was performed on 40% of patients (4/10), and interventional angiography was performed on 60% of patients (6/10). In-line flow was present in 0% (0/10) of the peroneal arteries, 60% (6/10) of the anterior tibial arteries, and 70% (7/10) of the posterior tibial arteries. Heel angiographic contrast blush was present in 60% (6/10), and intact plantar arch was present in 60% (6/10). Patients developed heel ulcerations at a mean time of 7.6 months (range 0.7 to 41.2) postoperatively. The incidence of major lower-extremity amputation was 30% (3/10), with a mean time of 5.2 months (range 3.5 to 8.3) from time of heel wound development. No amputation occurred in 6 patients (60%). Among them, intact anterior tibial inline arterial flow was present in 3, intact posterior tibial inline arterial flow was present in 6, and heel blush was present in 5. Our results demonstrate that an open calcaneal branch of the posterior tibial artery is sufficient to heal plantar heel ulcerations to potentially increase rates of limb salvage.

[General Treatment Strategy for Intervention in Lower Extremity Arterial Disease]

The prevalence of lower extremity disease is increasing with age. With recent technological advancements, endovascular treatment is being performed more frequently. The treatment goal of intermittent claudication is to improve walking and reduce claudication. To achieve these goals, anatomical durability and patency are important. In patients with critical limb ischemia, the lesions are diffuse and particularly severe in below-the-knee arteries. The treatment goal of critical limb ischemia is to promote wound healing and to prevent major amputation, which is evaluated by the limb salvage rate. Primary stenting using covered or bare metal stents is a widely accepted endovascular treatment. While drug-eluting technologies with or without atherectomy are widely used in the treatment of femoropopliteal disease, balloon angioplasty is the mainstay treatment for below-the-knee intervention. CT angiography provides a road map for planning endovascular treatment in patients without absolute contraindications.

A systematic review and meta-analysis of endovascular angiosomal revascularization in the setting of collateral vessels

OBJECTIVE

Endovascular procedures for targeted treatment of lower extremity wounds can be subdivided as direct revascularization (DR), indirect revascularization (IR), and IR via collateral flow (IRc). Although previous systematic reviews assert superiority of DR when compared with IR, the role of collateral vessels in clinical outcomes remains to be defined. This systematic review and meta-analysis aims to define the usefulness of DR, IR, and IRc in treatment of lower extremity wounds with respect to (1) wound healing, (2) major amputation, (3) reintervention, and (4) all-cause mortality.

METHODS

A meta-analysis was performed in accordance with PRISMA guidelines. Ovid MEDLINE was queried for records pertaining to the study question using appropriate Medical Subject Heading terms. Studies were limited to those using DR, IR, or IRc as a primary intervention and reporting information on at least one of the primary outcomes of interest. No limitation was placed on year of publication, country of origin, or study size. Studies were assessed for validity using the Newcastle-Ottawa Scale. Study characteristics and patient demographics were collected. Data representing the primary outcomes-wound healing, major amputation, reintervention, and all-cause mortality-were collected for time points ranging from one month to four years following intervention. A meta-analysis on sample size-weighted data assuming a random effects model was performed to calculate odds ratios (ORs) for the four primary outcomes at various time points.

RESULTS

We identified 21 studies for a total of 4252 limbs (DR, 2231; IR, 1647; IRC, 270). Overall wound healing rates were significantly superior for DR (OR, 2.45; P = .001) and IRc (OR, 8.46; P < .00001) compared with, IR with no significant difference between DR and IRc (OR, 1.25; P = .23). The overall major amputation rates were significantly superior for DR (OR, 0.48; P < .00001) and IRc (OR, 0.44; P = .006) compared with IR, with DR exhibiting significantly improved rates compared with IRc (OR, 0.51; P = .01). The overall mortality rates showed no significant differences between DR (OR, 0.89; P = .37) and IRc (OR, 1.12; P = .78) compared with IR, with no significant difference between DR and IRc (OR, 0.54; P = .18). The overall reintervention rates showed no significant difference between DR and IR (OR, 1.05; P = .81), with no studies reporting reintervention outcomes for IRc.

CONCLUSIONS

Both DR and IRc offer significantly improved wound healing rates and major amputation rates compared with IR when used to treat critical limb ischemia. Although DR should be the preferred method of revascularization, IRc can offer comparable outcomes when DR is not possible. This analysis was limited by a small sample size of IRc limbs, a predominance of retrospective studies, and variability in outcome definitions between studies.

Technical Success and Complication Rates of Retrograde Arterial Access for Endovascular Therapy for Critical Limb Ischaemia: A Systematic Review and Meta-Analysis

OBJECTIVE

Antegrade crossing techniques via transfemoral access are often challenging and may be associated with technical and clinical failure when treating patients with critical limb ischaemia (CLI). The objective of this study was to summarise all available literature regarding retrograde endovascular treatment of patients with CLI and to investigate the technical success and complication rate of retrograde access.

METHODS

A systematic literature search was performed in PubMed, Scopus, and Cochrane Central until May 2020. A meta-analysis of 31 observational studies (29 retrospective and two prospective; 26 and five studies with low and moderate risk of bias, respectively) was conducted with random effects modelling. The incidence of adverse events peri-procedurally and during follow up were calculated.

RESULTS

The 31 studies enrolled 1 910 patients who were treated endovascularly for femoropopliteal and/or infrapopliteal lesions causing CLI. Most of the patients had diabetes while more than half of the overall population had coronary artery disease and dyslipidaemia. All lesions were located in the infra-inguinal segment and most were chronic total occlusions (96%; 95% CI 85%-100%). Seven studies reported moderate or severe calcification in approximately half of the cases (45%; 95% CI 30%-60%). The overall technical success of the retrograde approach was 96% (18 studies; 95% CI 92%-100%). Perforation, flow limiting dissection, distal embolisation, and local haematoma at the retrograde access site were infrequent and observed in 2.1%, 0.6%, 0.1%, and 1.3% of the patients, respectively. The six month primary patency rate was 78% (five studies; 95% CI 46%-99%), the six month limb salvage rate was 77% (four studies; 95% CI 70%-84%).

CONCLUSION

The results indicated that the retrograde or bidirectional antegrade/retrograde approach is safe and effective and facilitates angioplasty when antegrade treatment fails. However, prospective studies with standardised wound care and surveillance protocols are needed to investigate retrograde techniques in patients with CLI who failed antegrade revascularisation, to improve long term limb salvage and survival.

Infrapopliteal endovascular intervention and the angiosome concept: intraoperative real-time assessment of foot regions' blood volume guides and improves direct revascularization

OBJECTIVE

There is no consensus for determining which vessel should be revascularized in patients with multiple diseased infrapopliteal arteries. The angiosome concept may guide a more efficient targeted direct revascularization. Therefore, we conducted a study to assess whether the regional evaluation of foot blood volume may guide direct revascularization (DR) and if it will lead to better perfusion improvement than indirect revascularization (IR).

METHODS

We performed a prospective single-center observational cohort study in patients treated in the Department of Vascular Surgery of Peking Union Medical College Hospital from November 2016 to April 2019. Twenty-seven patients treated with endovascular intervention were included. The intraoperative parenchymal blood volume of different foot regions was obtained for each patient using C-arm CT before and after intervention.

RESULTS

The intervention procedure significantly increased the overall blood volume (48.95 versus 81.97 ml/1000 ml, p = 0.002). Patients with direct revascularization had a 197% blood volume increase while patients with indirect revascularization had a 39% increase (p = 0.028). The preoperative blood volume was higher in patients with mild symptoms than in patients with severe symptoms (58.20 versus 30.45 ml/1000 ml, p = 0.039). However, in regard to postoperative blood volume, no significant difference was discovered between these two groups (75.05 versus 95.01 ml/1000 ml, p = 0.275).

CONCLUSION

Based on quantitative measurements, we conclude that overall blood volume can rise significantly after the intervention. Revascularizing the supplying vessel of the ischemic area directly will result in better perfusion improvement than restoring blood supply through the collateral circulation. Preoperative blood volume is associated with preoperative symptoms.

KEY POINTS

• Flat panel detector CT can obtain intraoperative perfusion status and guide treatment in endovascular intervention. • Revascularizing the supplying vessel of the ischemic area directly will result in better perfusion improvement than restoring the blood supply through the collateral circulation. • Patients with severer clinical manifestations have lower blood volumes.

Foot Angiosomes: Instructions for Use

In the last 15 years an abundance of literature has demonstrated that angiosome-targeted revascularization, either endovascular or open, can lead to better clinical results in patients with chronic limb-threatening ischemia. According to this literature, the angiosome concept should guide our treatment strategy in every chronic limb-threatening ischemia patient. However, in our daily practice, its application is often difficult or impossible. Most foot wounds spread over multiple angiosomes and, moreover, the value of an angiosome-guided revascularization approach can vary according to vascular anatomy, collateral vessel network, type of revascularization, and wound. The aim of this article is to explore values and limits of the angiosome concept, and to propose some “instructions for use” regarding its application in our daily practice.

WIfI Classification Versus Angiosome Concept: A Change in the Infrapopliteal Angioplasties Paradigm

OBJECTIVE

The objective of this study was to determine whether the angiosome concept and WIfI classification in patients undergoing endovascular treatment is associated with the limb salvage rate and wound healing rate in patients with critical limb ischemia(CLI).

METHODS

This was a retrospective, consecutive cohort study of CLI patients who underwent infrapopliteal angioplasty at the Vascular and Endovascular Surgery Service of the Hospital do Servidor Público Estadual, São Paulo, between January 2013 and January 2019. The primary outcome variable was the limb salvage rate and wound healing rate. The secondary outcome variables were patency, survival, time free from reintervention, and operative mortality rate.

RESULTS

Overall, 95 infrapopliteal endovascular procedures were performed in 95 patients. The initial technical success rate was 100%. The mean ± standard deviation outpatient follow-up time was 775 ± 107.5 days. The analyses were performed at 360 days for wound healing rate and 720 days for limb salvage rates, overall survival, and time freedom from reintervention. According to the angiosome concept, there were 54 patients (56.8%) classified in the direct group and 41 patients (43.2%) in the indirect group. Regarding the WIfI classification subanalysis, there were 22 patients WIfI 0-1 (23.2%) and 73 patients WIfI 2-3 (76.8%). Furthermore, the indirect group had a higher ulcer healing rate than the direct group; however, it was not statistically significant (82.9%; 66.7%%, respectively, P = 0.059). However, the time to heal the ulcer was faster in the WIfI 0-1 groups than WIfI 2-3 groups (164.82 days versus 251,48; P = 0.017). The limb salvage rates at 720 days were similar among indirect and direct Groups (92.6% and 85.4%, P = 0.79). Likewise, the freedom from reintervention rates at 720 days were also similar in Indirect and direct groups (74.6% and 64%, P = 0.23). The survival rates at 720 days were similar in both indirect and direct groups (86.8 and 85.6%, respectively; P = 0.82). The amputation free survival rate at 720 days by the Kaplan-Meier method was 91.3% in the indirect group and 85.9% in the direct group, but with no statistical significance between the groups (P = 0.37) CONCLUSIONS: This study concluded that, in endovascular treatment, the angiosome concept is no longer important to limb salvage rates, nor ulcer/wound healing rates. Moreover, the WIfI classification 0-1 is associated with faster and higher wound/ulcer healing rates than WIfI classification 2-3.

Guidelines on multidisciplinary approaches for the prevention and management of diabetic foot disease (2020 edition)

In recent years, as living standards have continued to improve, the number of diabetes patients in China, along with the incidence of complications associated with the disease, has been increasing. Among these complications, diabetic foot disease is one of the main causes of disability and death in diabetic patients. Due to the differences in economy, culture, religion and level of medical care available across different regions, preventive and treatment methods and curative results for diabetic foot vary greatly. In multidisciplinary models built around diabetic foot, the timely assessment and diagnosis of wounds and appropriate methods of prevention and treatment with internal and external surgery are key to clinical practice for this pathology. In 2019, under the leadership of the Jiangsu Medical Association and Chinese Diabetes Society, the writing group for the Guidelines on multidisciplinary approaches for the prevention and management of diabetic foot disease (2020 edition) was established with the participation of scholars from the specialist areas of endocrinology, burn injury, vascular surgery, orthopedics, foot and ankle surgery and cardiology. Drawing lessons from diabetic foot guidelines from other countries, this guide analyses clinical practices for diabetic foot, queries the theoretical basis and grades and gives recommendations based on the characteristics of the pathology in China. This paper begins with assessments and diagnoses of diabetic foot, then describes treatments for diabetic foot in detail, and ends with protections for high-risk feet and the prevention of ulcers. This manuscript covers the disciplines of internal medicine, surgical, nursing and rehabilitation and describes a total of 50 recommendations that we hope will provide procedures and protocols for clinicians dealing with diabetic foot.

Registry number: IPGRP-2020cn124

Angiosome～From the Standpoint of Bypass Surgery

Although several studies showed that angiosome-guided endovascular treatment improved wound healing and major amputation rates in patients with chronic limb-threatening ischemia (CLTI), effectiveness of the angiosome concept to the treatment of ischemic foot remains to be elucidated, especially in bypass surgery. Arterial anatomy of the foot and ankle shows that there are multiple supplementary circulation including arterial–arterial connections and choke nexus, which indicates angiosome concept may carry limited importance in bypass surgery for CLTI. On the other hand, patients with diabetes or renal dysfunction have partial occlusion of arterial–arterial connections and, therefore, quite a few patients with CLTI in Japan may present with limited but impaired supplementary circulation around the ankle. This article reviews the arterial anatomy and circulation of the foot and ankle and discusses availability and limitations of angiosome-guided bypass surgery.

Diagnostic and Therapeutic Approaches in the Management of Infrapopliteal Arterial Disease

Chronic limb-threatening ischemia represents end-stage peripheral artery disease. It is underdiagnosed; it relies on clinical symptoms and traditional noninvasive tests, which significantly underestimate the severity of disease. Innovative techniques, approaches, technologies, and risk-assessment tools have significantly improved our ability to treat these patients and to better understand their complex disease process. For patients with chronic limb-threatening ischemia considered without options, the reengineering of deep venous arterialization procedures has shown promising results. Finally, the creation of interactive and multidisciplinary teams in centers of excellence is of paramount importance to significantly improve the care and outcomes of these patients.

Effectiveness of revascularisation of the ulcerated foot in patients with diabetes and peripheral artery disease: A systematic review

In patients with diabetes, foot ulceration and peripheral artery disease (PAD), it is often difficult to determine whether, when and how to revascularise the affected lower extremity. The presence of PAD is a major risk factor for non-healing and yet clinical outcomes of revascularisation are not necessarily related to technical success. The International Working Group of the Diabetic Foot updated systematic review on the effectiveness of revascularisation of the ulcerated foot in patients with diabetes and PAD is comprised of 64 studies describing >13 000 patients. Amongst 60 case series and 4 non-randomised controlled studies, we summarised clinically relevant outcomes and found them to be broadly similar between patients treated with open vs endovascular therapy. Following endovascular revascularisation, the 1 year and 2 year limb salvage rates were 80% (IQR 78-82%) and 78% (IQR 75-83%), whereas open therapy was associated with rates of 85% (IQR 80-90%) at 1 year and 87% (IQR 85-88%) at 2 years, however these results were based on a varying combination of studies and cannot therefore be interpreted as cumulative. Overall, wound healing was achieved in a median of 60% of patients (IQR 50-69%) at 1 year in those treated by endovascular or surgical therapy, and the major amputation rate of endovascular vs open therapy was 2% vs 5% at 30 days, 10% vs 9% at 1 year and 13% vs 9% at 2 years. For both strategies, overall mortality was found to be high, with 2% (1-6%) perioperative (or 30 day) mortality, rising sharply to 13% (9-23%) at 1 year, 29% (19-48%) at 2 years and 47% (39-71%) at 5 years. Both the angiosome concept (revascularisation directly to the area of tissue loss via its main feeding artery) or indirect revascularisation through collaterals, appear to be equally effective strategies for restoring perfusion. Overall, the available data do not allow us to recommend one method of revascularisation over the other and more studies are required to determine the best revascularisation approach in diabetic foot ulceration.

Healing of Diabetic Neuroischemic Foot Wounds With vs Without Wound-Targeted Revascularization: Preliminary Observations From an 8-Year Prospective Dual-Center Registry

Purpose: To assess the clinical efficacy of endovascular angiosome-oriented wound-targeted revascularization (WTR) vs indirect (wound-indifferent) revascularization (IR) in diabetic patients with neuroischemic foot ulcers. Materials and Methods: Between April 2009 and July 2017, 167 diabetic patients (mean age 72.8 years; 137 men) with chronic limb-threatening ischemia (Rutherford category 5) and foot wounds (Wagner 2-4) in 194 limbs were prospectively registered and scheduled for primary infragenicular endovascular treatment. Specific angiosome source artery reperfusion sustained by patent foot arches or arterial-arterial connections was attempted initially. If this approach failed, topographic revascularization via available collaterals (WTRc) and IR were sequentially attempted. Results: Reperfusion was successful in 176 (91%) of 194 limbs (113 with WTR, 28 with WTRc, and 35 with IR); the global angiosome-oriented technical success (WTR and WTRc) was 73% (141/194). The mean follow-up was 10.9±0.7 months (range 3-12.5). Over 1 year, 102 (58%) of the 176 successfully treated limbs experienced wound healing [79/113 (70%) in the WTR group, 15/28 (54%) in the WTRc group, and 7/35 (20%) in the IR group; p=0.011]. The mean time to healing was 6.8±0.4 months in the WTR group, 7.9±0.6 months in the WTRc group, and 9.8±0.7 months in the IR group (p=0.001). Relapses were noted in 18 (16%) WTR limbs, 5 (18%) WTRc limbs, and 6 (17%) IR limbs. Comparison between WTR and IR and WTRc vs IR showed improved cicatrization in the angiosome-oriented groups (p<0.05). Major adverse limb events (MALE) and limb salvage were different between WTR and WTRc and between WTR and IR groups (p<0.05), while WTRc vs IR was not. Amputation-free survival was not influenced by the revascularization strategy (p=0.093). Conclusion: Wound healing in diabetic patients with chronic limb-threatening ischemia appeared to be improved by intentional wound-targeted revascularization, but no uniform benefit concerning MALE or limb preservation was observed. IR still represents an alternative for limb salvage in cases in which angiosome-guided revascularization fails.

Pilot study on the use of infrared thermal imaging to predict infrainguinal bypass outcome in the immediate post-operative period

Objectives

Early bedside post-operative monitoring of infrainguinal bypass surgery is currently based on subjective clinical findings and handheld Doppler signals. Infrared thermal imaging is an objective and reproducible technique that has been proven to be a reliable and accurate method to measure skin temperature. The aim of this prospective study was to assess infrared thermal imaging as a predicting tool of bypass graft outcome in the immediate post-operative period and assess the angiosome concept.

Methods

This was a prospective cohort study of 25 patients undergoing infrainguinal bypass. Demographic and clinical data were prospectively collected and included gender, age, co-morbidities, pre- and post-operative ankle brachial pressure indices, surgery undertaken and patency of run-off vessels. Infrared thermal imaging was undertaken pre- and post-operatively to assess thermal changes to the feet following revascularisation.

Results

We found that an increase in temperature from pre- to post-operative was significantly associated with bypass patency. An increase in temperature was found to have a positive predictive value of 75%, a negative predictive value of 100%, a sensitivity of 100% and specificity of 89% for predicting graft patency.

Conclusions

Infrared thermal imaging can be used to measure temperature related changes of the microcirculation post-operatively and predict bypass outcomes in the immediate post-operative period.

Multidisciplinary Care for Critical Limb Ischemia: Current Gaps and Opportunities for Improvement

Critical limb ischemia (CLI), defined as ischemic rest pain or nonhealing ulceration due to arterial insufficiency, represents the most severe and limb-threatening manifestation of peripheral artery disease. A major challenge in the optimal treatment of CLI is that multiple specialties participate in the care of this complex patient population. As a result, the care of patients with CLI is often fragmented, and multidisciplinary societal guidelines have not focused specifically on the care of patients with CLI. Furthermore, multidisciplinary care has the potential to improve patient outcomes, as no single medical specialty addresses all the facets of care necessary to reduce cardiovascular and limb-related morbidity in this complex patient population. This review identifies current gaps in the multidisciplinary care of patients with CLI, with a goal toward increasing disease recognition and timely referral, defining important components of CLI treatment teams, establishing options for revascularization strategies, and identifying best practices for wound care post-revascularization.

Angiosome perfusion of the foot: An old theory or a new issue?

The angiosome concept of foot perfusion was conceived based on anatomical studies of arterial circulation and used for planning surgical procedures, tissue reconstruction, and amputation. Its application is relevant in diabetic patients with critical limb ischemia and nonhealing foot ulcer or amputation. An understanding of foot angiosome anatomy is useful for predicting healing and planning arterial revascularization. A review of the literature, including the most recent systematic reviews and meta-analyses, indicates improved wound healing is achieved when the angiosome concept is followed. The greatest value of angiosome-based revascularization is in patients with lesion(s) limited to a single angiosome, or to achieve optimal healing of amputation sites. Future research should focus on proper identification of (imaging) modalities to determine the hemodynamic and functional changes before and after revascularization, thus identifying the "real" angiosome and directing optimal therapy.

Angiosome-Guided Intervention in Critical Limb Ischemia

The goals of treatment for critical limb ischemia (CLI) are alleviation of ischemic rest pain, healing of arterial insufficiency ulcers, and improving quality of life, thereby preventing limb loss and CLI-related mortality. Arterial revascularization is the foundation of a contemporary approach to promote amputation-free survival. Angiosome-directed revascularization has become a popular theory of reperfusion, whereby anatomically directed arterial flow is restored straight to the wound bed. Innovations in endovascular revascularization combined with a multidisciplinary strategy of wound care accelerate progress in CLI management. This article highlights advances in CLI management, including the clinical relevance of angiosome-directed revascularization, and provides considerations for future treatment of CLI.

Predictors of delayed wound healing after successful isolated below-the-knee endovascular intervention in patients with ischemic foot ulcers

OBJECTIVE

The purpose of this study was to explore the predictors of delayed wound healing and their use in risk stratification for endovascular treatment (EVT) of patients with critical limb ischemia (CLI) due to isolated below-the-knee lesions.

METHODS

Wound healing rates were analyzed retrospectively in patients who underwent successful below-the-knee percutaneous transluminal balloon angioplasty for CLI with tissue loss between May 2008 and June 2013. We also analyzed the independent predictors of delayed wound healing and their use in risk stratification.

RESULTS

The cumulative wound healing rates were 13.9%, 43.8%, 57.7%, and 65.7% at 3, 6, 9, and 12 months, respectively. Multivariate Cox proportional hazards analysis revealed the following as independent predictors of wound nonhealing after initial successful EVT: patients with end-stage renal disease receiving dialysis (hazard ratio [HR], 2.6; 95% confidence interval [CI], 1.0-6.3; P  = .04); albumin level <3.0 g/dL (HR, 2.0; 95% CI, 1.1-3.8; P  = .02); C-reactive protein level >5.0 mg/dL (HR, 3.9; 95% CI, 1.6-9.6; P = .003); major tissue loss (HR, 2.1; 95% CI, 1.3-3.4; P = .003); wound infection (HR, 1.9; 95% CI, 1.2-2.9; P = .005); gangrene (HR, 1.8; 95% CI, 1.2-2.8; P = .008); wound depth (University of Texas grade 3; HR, 3.4; 95% CI, 1.4-8.6; P = .009); duration of ulcer (≥2 months; HR, 2.9; 95% CI, 1.0-8.4; P = .048); insulin use (HR, 1.7; 95% CI, 1.0-2.8; P = .04); and lack of below-the-ankle runoff (HR, 1.9; 95% CI, 1.0-3.4; P = .04).

CONCLUSIONS

The general status of the patient and the target limb's condition are important predictors of wound nonhealing. Regarding the limb's condition, information on wound depth and duration in addition to wound extent and infection would further enable the selection of suitable CLI patients for EVT. Such information would also enable optimal wound management, leading to successful wound healing and improved limb salvage and survival rates.

Indocyanine Green Angiography to Prognosticate Healing of Foot Ulcer in Critical Limb Ischemia: A Novel Technique

BACKGROUND

To predict wound healing in patients with critical limb ischemia (CLI) is an ongoing issue. Current methods such as ankle-brachial index (ABI), color Doppler and transcutaneous oxygen pressure (TCPO₂), and computed tomography angiography are lacking in demonstrating regional perfusion. Indocyanine green angiography (ICGA) has the potential to provide regional perfusion information lacking in other methods. This study was conducted to demonstrate successes of revascularization procedure in CLI patients based on ICGA data.

METHODS

A total of 47 patients with grade 2 or grade 3 University of Texas Wound Classification System ischemic foot ulcer undergoing lower limb revascularization procedure were included in this study, from July 2014 to May 2016. ICGA with intravenous 0.1 mg/kg of 0.1% indocyanine green dye was performed before and after revascularization procedure. ICGA data maximum unit, blush time, and blush rate were compared between prerevascularization and postrevascularization data, along with ABI and TCPO₂.

RESULTS

Out of 47 patients (45 males and 2 females), 43 underwent endovascular revascularization and 4 underwent open procedure. Of all, 76.6% of patients were diabetic and 46.8% were hypertensive. Also, 31.9% had coronary artery disease, 21.2% had history of cerebrovascular disease, 23% had chronic kidney disease, and 74.4% were chronic smokers. A total of 37 patients' ulcer healed completely on follow-up with significant improvement (P < 0.05) in preoperative and postoperative ABI, TCPO₂, and ICGA data. Ten patients' ulcer did not heal in the follow-up period. In those 10 patients, preoperative and postoperative ABI and TCPO₂ improved, but ICGA data were not improved postoperatively (P > 0.05).

CONCLUSIONS

ICGA is an evolving tool to quantify regional perfusion in CLI. ICGA parameters provide qualitative real-time visual images of perfusion in area of interest as well as quantitative information of perfusion.

Collateral circulation between angiosomes in the feet of diabetic patients

Objectives The main factor in the healing of foot ulcers in diabetic patients is adequate perfusion. There is no consensus on whether direct or indirect revascularization is more effective in leg revascularization. At the centre of that debate, there is a disagreement about whether collateral circulation is sufficient or not. Our aim is to evaluate collateral circulation activity between angiosomes in the feet of diabetic patients by evaluating the level of occlusion in leg arteries and comparing the angiosome regions that have necrosis. Methods The study included 61 patients. All had undergone CT angiography to the lower extremity prior to any revascularization of the leg arteries between September 2014 and September 2016. Stenosis was evaluated on the anterior tibial artery, the posterior tibial artery and the peroneal artery up to the level of the ankle. The opening of the vessel wall at the narrowest part of the vessel was determined as a percentage. The areas with necrosis were determined according to the angiosomes of the posterior tibial artery, anterior tibial artery and peroneal artery vessels. Results Necrosis of the foot was most common in the posterior tibial artery angiosome. Necrosis in the posterior tibial artery angiosome was independent of the level of posterior tibial artery occlusion; however, it was associated with the occlusion of the anterior tibial artery ( p < 0.05). It was found that anterior tibial artery occlusion over 15% resulted in necrosis in the posterior tibial artery angiosome. Conclusions Collateral circulation between the anterior tibial artery and posterior tibial artery is active and there is almost always occlusion in the posterior tibial artery branches. The posterior tibial artery angiosome is fed by the collateral arteries of the anterior tibial artery even if there is no occlusion of posterior tibial artery at the level of the leg, so indirect revascularization on the anterior tibial artery is sufficient to provide foot circulation.

Axillobifemoral Bypasses: Reappraisal of an Extra-Anatomic Bypass by Analysis of Results and Prognostic Factors

BACKGROUND

Axillobifemoral bypass (AFB) is method of second choice. It is reserved for patients at high operative risk or to bypass infected vessels or grafts. In this study, we analyzed prognostic factors for AFB patency and limb salvage rate to facilitate the choice of procedure.

METHODS

Between Jan 2006 and Aug 2013, 45 patients underwent AFB surgery in our department, 24 for critical limb ischemia (CLI) and 23 for infection. Endpoints of study were graft occlusion, graft infection, amputation and patient's death. Prognostic factors were compared by univariate analysis for each indication group. Mean follow-up was 40.2 (±23.2) months.

RESULTS

Complication rate was significantly higher in infection group (88.0 vs. 54.4%, p = 0.003) and in emergency surgery (83.3 vs. 56.9%, p = 0.023). Overall primary patency rate after AFB procedures was 66.7% after 1, 3, and 5 years, while secondary patency rate was 91.1% after 1 year, 82.2% after 3 years and 80.0% after 5 years. The primary and secondary patency rates did not significantly differ between the both groups (p = 0.059 and p = 0.136). Following prognostic factors showed a statistically significant influence on patency rates in CLI group: >1 previous vascular surgical intervention, patch angioplasty at the distal anastomosis site, complications after previous vascular surgery, and perioperative intake of platelet aggregation inhibitor. Only the employed bypass material had a statistical significant influence on the secondary patency rates in the infection group. Overall limb salvage rate was 82.2% after 1 year, 80.0% after 3 years and 77.8% after 5 years. There were statistically significant differences in the limb salvage rates depending on emergency surgery and a 3-vessel-run-off in the lower leg in both indication groups.

CONCLUSION

AFB have acceptable patency and limb salvage rates. AFB is a good alternative in patients with CLI at high operative risk or with infections of aortoiliac segments, even with endovascular approaches. They remain essential tools in vascular surgeon's repertoire.

Angiosome-directed revascularization in patients with critical limb ischemia

OBJECTIVE

Direct revascularization (DR), according to the angiosome concept, provides direct blood flow to the site of tissue loss in patients with critical limb ischemia (CLI). DR may lead to improved outcomes; however, evidence for this is controversial. This systematic review and meta-analysis investigated the outcomes of surgical and endovascular DR compared with indirect revascularization (IR) in patients with CLI.

METHODS

A systematic review was undertaken using the Cochrane Collaboration specified tool, and a meta-analysis was done according to the MOOSE (Meta-analysis of Observational Studies in Epidemiology) criteria. The electronic databases of MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials were systematically searched for studies of DR compared with IR in patients with CLI with tissue loss. All articles were critically assessed for relevance, validity, and availability of data regarding patient and lesion characteristics and outcomes. When possible, data were systematically pooled, and a meta-analysis was performed for wound healing, major amputation, amputation-free survival, and overall survival.

RESULTS

Of 306 screened abstracts, 19 cohort studies with 3932 patients were included. Nine scored 7 or higher on the Newcastle-Ottawa score. DR significantly improved wound healing (risk ratio [RR], 0.60; 95% confidence interval [CI], 0.51-0.71), major amputation (RR, 0.56; 95% CI, 0.47-0.67), and amputation-free survival rates (RR, 0.83; 95% CI, 0.69-1.00) compared with IR. This significance was lost in major amputation on sensitivity analysis for bypass studies. No significant difference was found in overall survival. In studies stratifying for collaterals, no differences between DR and IR were found in wound healing or major amputations in the presence of collaterals.

CONCLUSIONS

DR significantly improves wound healing and major amputation rates after endovascular treatment in patients with CLI, supporting the angiosome theory. In the presence of collaterals, outcomes after IR are similar to outcomes after DR. Alternatively, patients without collaterals may benefit even more from DR as a primary treatment strategy. The angiosome theory is less applicable in bypass surgery, because bypasses are generally anastomosed to the least affected artery, with runoff passing the ankle to maintain bypass patency.

2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines

Since 1980, the American College of Cardiology (ACC) and American Heart Association (AHA) have translated scientific evidence into clinical practice guidelines with recommendations to improve cardiovascular health. These guidelines, based on systematic methods to evaluate and classify evidence, provide a cornerstone of quality cardiovascular care.

In response to reports from the Institute of Medicine1 ,2 and a mandate to evaluate new knowledge and maintain relevance at the point of care, the ACC/AHA Task Force on Clinical Practice Guidelines (Task Force) modified its methodology.3 –5 The relationships among guidelines, data standards, appropriate use criteria, and performance measures are addressed elsewhere.5

2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines

Since 1980, the American College of Cardiology (ACC) and American Heart Association (AHA) have translated scientific evidence into clinical practice guidelines with recommendations to improve cardiovascular health. These guidelines, based on systematic methods to evaluate and classify evidence, provide a cornerstone of quality cardiovascular care.

In response to reports from the Institute of Medicine1 ,2 and a mandate to evaluate new knowledge and maintain relevance at the point of care, the ACC/AHA Task Force on Clinical Practice Guidelines (Task Force) modified its methodology.3 –5 The relationships among guidelines, data standards, appropriate use criteria, and performance measures are addressed elsewhere.5

Clinical outcome of angiosome-oriented infrapopliteal percutaneous transluminal angioplasty for isolated infrapopliteal lesions in patients with critical limb ischemia

PURPOSE

We aimed to evaluate the clinical usefulness and outcome of angiosome-oriented percutaneous transluminal angioplasty (IP-PTA) and its clinical outcome for isolated infrapopliteal lesions in diabetic critical limb ischemia.

METHODS

We retrospectively reviewed 70 patients (82 limbs) with diabetic critical limb ischemia who had localized disease at the level of the infrapopliteal artery. Patients underwent IP-PTA between January 2011 and December 2013 and were followed up for a mean of 13 months. The primary target arterial lesions were chosen according to the angiosome concept. We evaluated clinical findings, technical success, and patients' clinical outcome. The angiographic outcome of IP-PTA was assessed using the angiosome score. We analyzed the relationship between the angiosome score and the amputation rate.

RESULTS

There were 69 anterior tibial artery (ATA) lesions, 70 posterior tibial artery (PTA) lesions, and 58 peroneal artery (PA) lesions. The primary target arteries were the ATA (n=43), PTA (n=26), PA (n=2), and ATA + PTA (n=11). We divided the treated limbs into target (n=63) and nontarget (n=19) groups. The overall initial technical success rate was 91.4%. Successful wound healing rates were 87.3% (55/63) and 47.3% (9/19) in the target and nontarget groups, respectively (P < 0.05).

CONCLUSION

Angiosome-oriented primary targeted IP-PTA shows a highly effective treatment outcome in diabetic critical limb ischemia. In cases with inadequate angioplastic results of the target artery, IP-PTA of the nontarget artery should be recommended to improve the limb salvage rates.

Clinical effects of single or double tibial artery revascularization in critical limb ischemia patients with tissue loss

OBJECTIVE

The achievement of single vessel inflow to the wound is an acceptable end point of peripheral vascular intervention for patients with critical limb ischemia (CLI) with tissue loss. However, CLI patients often have multitibial artery lesions. We evaluated the clinical effects of single or double tibial artery revascularization for CLI patients.

METHODS

This study was conducted retrospectively in a single center. Between April 2007 and January 2015, we treated 123 CLI patients (137 limbs) who had lesions in both the anterior tibial artery and the posterior tibial artery. Of these, single tibial artery (anterior or posterior tibial artery) revascularization was performed in 84 limbs (group S) and double tibial artery (both anterior and posterior tibial arteries) revascularization was performed in 53 limbs (group D).

RESULTS

The wound healing rate was significantly higher (87% vs 79%; P = .003), the time to wound healing was shorter (median, 83 vs 142 days; P = .01), and the repeat peripheral vascular intervention rate was lower (15% vs 35%; P = .03) in group D than in group S. The wound healing rate was nearly similar between the 2 groups in patients with a low clinical stage as assessed by Society for Vascular Surgery Wound, Ischemia, and foot Infection (90% in group D vs 93% in group S; P = .20); however, the wound healing rate was significantly higher in group D in patients with a high clinical stage (85% vs 72%; P = .007).

CONCLUSIONS

The achievement of double vessel inflows to the wound by double tibial artery revascularization positively affects wound healing, particularly in severe CLI patients.

The Angiosome Concept Evaluated on the Basis of Microperfusion in Critical Limb Ischemia Patients-an Oxygen to See Guided Study

OBJECTIVES

Aim of this clinical study was to evaluate the angiosome concept with regard to the microcirculation of the foot in patients with CLI and to evaluate its relevance by means of combined laser Doppler flowmetrie and white-light tissue spectrophotometry.

METHODS

Twenty-eight patients who underwent leg revascularization in the stage of CLI were prospectively examined. The microperfusion was assessed by light guided spectrophotometry. The measuring points were set according to the angiosome concept into direct and indirect revascularized areas of the foot. Investigations were performed pre and postinterventionally and after 4 and 12 weeks in baseline-position as well as in an elevated position of the leg.

RESULTS

Microcirculation parameters (oxygen saturation, blood flow, velocity) of the revascularized leg showed a significant increase in elevation and baseline position compared to the preoperative values in most analyses. No significant differences between the direct and indirect revascularized angiosome were apparent.

CONCLUSION

The light-guided spectrophotometry measurement proved to be feasible in terms of measuring changes in the microcirculation after leg revascularization. However, our data do not support the value of the "angiosome concept" concerning the individual changes in microperfusion of the foot in patients with CLI.

[Treatment of below the knee lesions: Broadening the limits of vascular surgery]

One third of patients with critical limb ischemia (CLI) has below the knee lesions and requires a restoration of direct blood flow into the foot. However, many of these patients are ineligible for open surgery. The primary goals thus become pain relief and limb salvage over patency. The angiosome concept helps determine the target artery to treat in priority. The endovascular approach has decreased morbidity and mortality rates compared to distal bypass surgery; while subintimal retrograde, trans-collateral and loop techniques push the limits of open surgery by reopening the plantar arch, thereby improving run-off. Early restenosis phenomena after angioplasty have been improved by the use of - limus drug eluting balloons and balloon expandable stents in case of flow limiting dissection or recoil with increased limb salvage rates. Moreover, drug-eluting stents have been proposed, and allow a reduction in reintervention and in-stent restenosis rates in short lesions; however, results on amputation rates or survival are limited. Vessel preparation is a key to overcoming some current limitations, including atherectomy, which increases technical success rates and reduces restenosis rates, especially in calcified lesions, chronic total occlusions and restenosis. These advanced techniques in distal endovascular revascularization have revolutionized limb salvage and support the interest of an endovascular first approach in CLI treatment.