Systematic Review and Meta-analysis of Direct Versus Indirect Angiosomal Revascularisation of Infrapopliteal Arteries

Successful revascularization of the occluded anterior tibial artery using ultrasound-guided puncture of the occluded dorsal pedal artery: A case report with literature review

A bidirectional approach is necessary for treating critical limb ischemia with complex, multiple lesions. We report an ultrasound-guided bidirectional puncture through an occluded vessel to treat an obstruction extending from the anterior tibial artery to the dorsal foot artery in a patient with toe gangrene and rest pain. This technique effectively restored arterial patency and is a promising approach for managing challenging critical limb ischemia occlusions.

2024 ACC/AHA/AACVPR/APMA/ABC/SCAI/SVM/SVN/SVS/SIR/VESS Guideline for the Management of Lower Extremity Peripheral Artery Disease: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2024 ACC/AHA/AACVPR/APMA/ABC/SCAI/SVM/SVN/SVS/SIR/VESS Guideline for the Management of Lower Extremity Peripheral Artery Disease" provides recommendations to guide clinicians in the treatment of patients with lower extremity peripheral artery disease across its multiple clinical presentation subsets (ie, asymptomatic, chronic symptomatic, chronic limb-threatening ischemia, and acute limb ischemia).

METHODS

A comprehensive literature search was conducted from October 2020 to June 2022, encompassing studies, reviews, and other evidence conducted on human subjects that was published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through May 2023 during the peer review process, were also considered by the writing committee and added to the evidence tables where appropriate.

STRUCTURE

Recommendations from the "2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with peripheral artery disease have been developed.

2024 ACC/AHA/AACVPR/APMA/ABC/SCAI/SVM/SVN/SVS/SIR/VESS Guideline for the Management of Lower Extremity Peripheral Artery Disease: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2024 ACC/AHA/AACVPR/APMA/ABC/SCAI/SVM/SVN/SVS/SIR/VESS Guideline for the Management of Lower Extremity Peripheral Artery Disease" provides recommendations to guide clinicians in the treatment of patients with lower extremity peripheral artery disease across its multiple clinical presentation subsets (ie, asymptomatic, chronic symptomatic, chronic limb-threatening ischemia, and acute limb ischemia).

METHODS

A comprehensive literature search was conducted from October 2020 to June 2022, encompassing studies, reviews, and other evidence conducted on human subjects that was published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through May 2023 during the peer review process, were also considered by the writing committee and added to the evidence tables where appropriate.

STRUCTURE

Recommendations from the "2016 AHA/ACC Guideline on the Management of Patients With Lower Extremity Peripheral Artery Disease" have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with peripheral artery disease have been developed.

Oxygen Saturation Increase in Ischemic Wound Tissues after Direct and Indirect Revascularization

BACKGROUND

The primary approach for treating ischemic wounds is restoring oxygen supply to the ischemic region. While direct angiosomal revascularization is often associated with better post-operative wound healing and limb salvage, its superiority over non-angiosomal revascularization remains controversial. This study aimed to compare intraoperative tissue oxygen saturation changes in ischemic zones following either direct or indirect revascularization in below-the-knee arteries.

METHODS

This prospective observational study included patients undergoing direct and indirect below-the-knee endovascular revascularizations. Assignment to the groups was not randomized. Near-infrared spectroscopy was used to monitor rSO2 changes near the ischemic wounds intraoperatively. The changes were compared between the groups.

RESULTS

15 patients (50%) underwent direct angiosomal revascularization, while an equal number of patients underwent indirect revascularization. Overall, a statistically significant increase in regional oxygen saturation was observed after revascularization (p = 0.001). No statistically significant difference was found between the direct and indirect revascularization groups (p = 0.619).

CONCLUSIONS

This study revealed a minor difference in the oxygen saturation increase between the angiosomal and non-angiosomal revascularization groups. Such a finding indicates that the clinical significance of angiosomal revascularization is negligible and might be concealed by confounding factors, such as the vessel diameter and outflow impact on the restenosis rate.

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.

How much flow is enough: the use of fractional flow reserve in chronic limb-threatening ischemia in a series of patients with isolated occlusive tibial disease

The role of the fractional flow reserve to guide lower extremity peripheral vascular intervention, specifically in chronic limb-threatening ischemia, has remained unclear. This series presents a novel use of the fractional flow reserve in four patients to guide lower extremity endovascular interventions in patients with chronic limb-threatening ischemia.

Analyses of transcutaneous oxygen pressure values stratified for foot angiosomes to predict diabetic foot ulcer healing

AIMS

Previous research suggested that diabetic foot ulcer (DFU) location could affect transcutaneous oxygen pressure (TcPO2) values following the angiosome concept. Up to our knowledge no studies have yet analyzed if the location of a diabetic foot ulcer can be a confounding factor that modifies TcPO2 values. The primary aim of this study was to compare the potential healing prognosis of TcPO2 differentiated for diabetic foot ulcers in different angiosome locations.

METHODS

a 2-years observational cohort prospective study was performed in 81 patients with diabetic foot ulcers. Transcutaneous oxygen pressure measurements were performed at baseline by placing the electrode on two different angiosomes: dorsal zone of the foot (dorsalis pedis angiosome) and between the navicular bone and the tibial malleolus (posterior tibial angiosome). The main outcome was establishing the effectiveness of TcPO2 measurements (dorsalis pedis angiosome and posterior tibial angiosome) for predicting DFU healing.

RESULTS

Transcutaneous oxygen pressure probe placed in the dorsum of the foot (dorsalis pedis angiosome) yielded a sensitivity (S) of 95 % and specificity (SP) of 73 %, and an area under the curve (AUC) of 0.902 (p < 0.001 [0.84-0.96]) for ulcers located in the forefoot and toes; while TcPO2 placed in the posterior tibial angiosome yielded an S of 100 % and SP of 85 % and an AUC of 0.894 (p < 0.001 [0-822-0.966]) for DFU located in the midfoot and heel.

CONCLUSION

This study suggests that angiosome-guided TcPO2 contributes to a prognosis of successful foot ulcer healing.

Chronic Limb-Threatening Ischemia and the Need for Revascularization

BACKGROUND

Patients presenting with critical limb-threatening ischemia (CLTI) have been increasing in number over the years. They represent a high-risk population, especially in terms of major amputation and mortality. Despite multiple guidelines concerning their management, it continues to be challenging. Decision-making between surgical and endovascular procedures should be well established, but there is still a lack of consensus concerning the best treatment strategy. The aim of this manuscript is to offer an overview of the contemporary management of CLTI patients, with a focus on the concept that evidence-based revascularization (EBR) could help surgeons to provide more appropriate treatment, avoiding improper procedures, as well as too-high-risk ones.

METHODS

We performed a search on MEDLINE, Embase, and Scopus from 1 January 1995 to 31 December 2022 and reviewed Global and ESVS Guidelines. A total of 150 articles were screened, but only those of high quality were considered and included in a narrative synthesis.

RESULTS

Global Vascular Guidelines have improved and standardized the way to classify and manage CLTI patients with evidence-based revascularization (EBR). Nevertheless, considering that not all patients are suitable for revascularization, a key strategy could be to stratify unfit patients by considering both clinical and non-clinical risk factors, in accordance with the concept of individual residual risk for every patient. The recent BEST-CLI trial established the superiority of autologous vein bypass graft over endovascular therapy for the revascularization of CLTI patients. However, no-option CLTI patients still represent a critical issue.

CONCLUSIONS

The surgeon's experience and skillfulness are the cornerstones of treatment and of a multidisciplinary approach. The recent BEST-CLI trial established that open surgical peripheral vascular surgery could guarantee better outcomes than the less invasive endovascular approach.

Grades of Below-the-Ankle Arterial Occlusive Disease following the Angiosome Perfusion: A New Morphological Assessment and Correlations with the Inframalleolar GVG Stratification in CLTI Patients

PURPOSE

To assess a specific classification of the foot atherosclerotic disease concerning the angiosomal source arteries, the connected foot arches and attached collaterals for Rutherford 5, CLTI patients. To compare eventual analogies of this novel grading system with previously reported GLASS/GVG inframalleolar patterns of occlusive disease (P0-P2).

MATERIALS AND METHODS

A series of 336 ischemic feet (221 diabetics) were selected and retrospectively analyzed. For each angiographic pattern of inframalleolar atherosclerotic disease, 4 severity classes of targeted angiosomal artery path (TAAP), associating 4 other classes concerning linked foot arches (LFA) and collaterals occlusive disease were described. By associating the 4 TAAP with the 4 others parallel LFA and collaterals classes, 4 novel anatomical "Grades" (A-D) of occlusive disease were described. Limb salvage was studied between groups of diabetic and non-diabetic patients.

RESULTS

Using a primary endovascular approach, limb preservation comparison of grade A/B proved without significance for diabetics (P = 0.032) and non-diabetics (P = 0.226). Comparison in diabetics and/or non-diabetics between A/C (P = 0.045 and 0.046), A/D (P = 0.027 and 0.030, B/C (P = 0.009 and 0.038), and B/D (P = 0.006 and P = 0.042), as well as C/D groups (P = 0.048 and P = 0.034) proved ponderous. Parallel analysis of similar grades (A/A, B/B, etc.) with, or without diabetes appeared without significance (P > 0.05). Further comparison between grades A+B (assigned as P0/GVG), versus C (P1), and D (P2), proved significant (P < 0.0001).

CONCLUSION

The present grading system proposes a useful correlation between the severity of foot angiosomal arteries, arches, and collaterals disease and limb salvage, confirming the clinical significance of P0-P2 GVG severity score. This analysis also points the limits of EVT to be probably avoided in grade D patients.

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.

Effect of Direct Endovascular Revascularization Based on the Angiosome Model on Risk of Major Amputations and Life Expectancy in Type 2 Diabetic Patients with Critical Limb Ischemia and Foot Ulceration

BACKGROUND

We evaluated whether direct or indirect endovascular revascularization based on the angiosome model affects outcomes in type 2 diabetes and critical limb ischemia.

METHODS

From 2010 to 2015, 603 patients with type 2 diabetes were admitted for critical limb ischemia and submitted to endovascular revascularization. Among these patients, 314 (52%) underwent direct and 123 (20%) indirect revascularization, depending on whether the flow to the artery directly feeding the site of ulceration, according to the angiosome model, was successfully acquired; 166 patients (28%) were judged unable to be revascularized. Outcomes were healing, major amputation, and mortality rates.

RESULTS

An overall healing rate of 62.5% was observed: patients who did not receive percutaneous transluminal angioplasty presented a healing rate of 58.4% (P < .02 versus revascularized patients). A higher healing rate was observed in the direct versus the indirect group (82.4% versus 50.4%; P < .001). The major amputation rate was significantly higher in the indirect versus the direct group (9.2% versus 3.2%; P < .05). The overall mortality rate was 21.6%, and it was higher in the indirect versus the direct group (24% versus 14%; P < .05).

CONCLUSIONS

These data show that direct revascularization of arteries supplying the diabetic foot ulcer site by means of the angiosome model is associated with a higher healing rate and lower risk of amputation and death compared with the indirect procedure. These results support use of the angiosome model in type 2 diabetes with critical limb ischemia.

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.

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.

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.

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.

SPECT/CT Imaging: A Noninvasive Approach for Evaluating Serial Changes in Angiosome Foot Perfusion in Critical Limb Ischemia

Objective: To investigate the feasibility of serial radiotracer-based imaging as a noninvasive approach for quantifying volumetric changes in microvascular perfusion within angiosomes of the foot following lower extremity revascularization in the setting of critical limb ischemia (CLI).

Approach: A CLI patient with a nonhealing foot ulcer underwent single-photon emission computed tomography (SPECT)/computed tomography (CT) imaging of the feet before and after balloon angioplasty of the superficial femoral artery (SFA) and popliteal artery. SPECT/CT imaging was used to evaluate serial changes in angiosome perfusion, which was compared to quantitative changes in peripheral vascular anatomy and hemodynamics, as assessed by standard clinical tools that included digital subtraction angiography (DSA), ankle-brachial index (ABI), and toe-brachial index (TBI).

Results: Following revascularization, upstream quantitative improvements in stenosis of the SFA (pre: 35.4% to post: 11.9%) and popliteal artery (pre: 59.1% to post: 21.7%) shown by DSA were associated with downstream angiosome-dependent improvements in SPECT microvascular foot perfusion that ranged from 2% to 16%. ABI measurement was not possible due to extensive arterial calcification, while TBI values decreased from 0.26 to 0.16 following revascularization.

Innovation: This is the first study to demonstrate the feasibility of assessing noninvasive volumetric changes in angiosome foot perfusion in response to lower extremity revascularization in a patient with CLI by utilizing radiotracer-based imaging.

Conclusion: SPECT/CT imaging allows for quantification of serial perfusion changes within angiosomes containing nonhealing ulcers and provides physiological assessment that is complementary to conventional anatomical (DSA) and hemodynamic (ABI/TBI) measures in the evaluation of lower extremity revascularization.

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.

Editor's Choice - Impact of Endovascular Pedal Artery Revascularisation on Wound Healing in Patients With Critical Limb Ischaemia

OBJECTIVE

The present study investigated the impact of endovascular pedal artery revascularisation (PAR) on the clinical outcomes of patients with critical limb ischaemia (CLI).

METHODS

This retrospective analysis of a single centre cohort included 239 patients who underwent endovascular revascularisation of infrapopliteal arteries for a chronic ischaemic wound. PAR was attempted in 141 patients during the procedure. After propensity score matching, there were 87 pairs of patients with and without PAR.

RESULTS

After the matching, the two groups showed balanced baseline clinical and lesion characteristics. PAR was achieved in 60.9% of the PAR group. Direct angiosome flow was more frequently obtained in the PAR group than in the non-PAR group (81.6% vs. 34.5%; p < .001). Subintimal angioplasty (47.1% vs. 29.9%; p = .019) and pedal-plantar loop technique (18.4% vs. 0%; p < .001) were more frequent in the PAR group. At the one year follow up, the PAR group showed greater freedom from major amputation (96.3% vs. 84.2%; p = .009). The wound healing rate, overall survival, major adverse limb event, and freedom from re-intervention did not differ significantly between the two groups. However, the patient subgroup with successful PAR showed a higher wound healing rate than the non-PAR group (76.0% vs. 67.0%; p = .031). In a multivariable Cox proportional hazards regression model, successful PAR (hazard ratio [HR] 1.564, 95% confidence interval [CI] 1.068-2.290; p = .022) was identified as an independent factor associated with improved wound healing, whereas gangrene (HR 0.659, 95% confidence interval [CI] 0.471-0.923; p = .015), C reactive protein >3 mg/dL (HR 0.591, 95% CI 0.386-0.904; p = .015), and pre-procedural absence of pedal arch (HR 0.628, 95% CI 0.431-0.916; p = .016) were associated with impaired wound healing.

CONCLUSION

Successful PAR significantly improved wound healing in patients with CLI. Thus, efforts should be made to revascularise the pedal arteries, especially when the pedal arch is completely absent.

Radiotracer Imaging Allows for Noninvasive Detection and Quantification of Abnormalities in Angiosome Foot Perfusion in Diabetic Patients With Critical Limb Ischemia and Nonhealing Wounds

Background:

Single photon emission computed tomography (SPECT)/computed tomography (CT) imaging allows for assessment of skeletal muscle microvascular perfusion but has not been quantitatively assessed in angiosomes, or 3-dimensional vascular territories, of the foot. This study assessed and compared resting angiosome foot perfusion between healthy subjects and diabetic patients with critical limb ischemia (CLI). Additionally, the relationship between SPECT/CT imaging and the ankle–brachial index—a standard tool for evaluating peripheral artery disease—was assessed.

Methods and Results:

Healthy subjects (n=9) and diabetic patients with CLI and nonhealing ulcers (n=42) underwent SPECT/CT perfusion imaging of the feet. CT images were segmented into angiosomes for quantification of relative radiotracer uptake, expressed as standardized uptake values. Standardized uptake values were assessed in ulcerated angiosomes of patients with CLI and compared with whole-foot standardized uptake values in healthy subjects. Serial SPECT/CT imaging was performed to assess uptake kinetics of technetium-99m-tetrofosmin. The relationship between angiosome perfusion and ankle–brachial index was assessed via correlational analysis. Resting perfusion was significantly lower in CLI versus healthy subjects (P=0.0007). Intraclass correlation coefficients of 0.95 (healthy) and 0.93 (CLI) demonstrated excellent agreement between serial perfusion measurements. Correlational analysis, including healthy and CLI subjects, demonstrated a significant relationship between ankle–brachial index and SPECT/CT (P=0.01); however, this relationship was not significant for diabetic CLI patients only (P=0.2).

Conclusions:

SPECT/CT imaging assesses regional foot perfusion and detects abnormalities in microvascular perfusion that may be undetectable by conventional ankle–brachial index in patients with diabetes mellitus. SPECT/CT may provide a novel approach for evaluating responses to targeted therapies.

Achilles Tendinopathy and Associated Disorders

Degenerative disorders of the Achilles tendon are common, affecting up to 18% of the adult population. A thorough evaluation including a focused history, physical examination, and diagnostic studies helps in choosing the appropriate treatment. Initial treatment is usually nonoperative, consisting of activity modification, bracing, and physical therapy. Patents who fail nonoperative management may be treated operatively with a wide range of procedures from endoscopic surgery to open debridement and tendon transfer. Understanding a patient’s expectations and educating patients about potential treatments and their outcomes enables informed collaborative decision making. This article will review the evaluation and management Achilles tendinopathy and associated disorders.

Clinical Assessment of Peripheral Arterial Disease in the Office: What Do the Guidelines Say?

Lower extremity peripheral arterial disease (PAD) is the manifestation of atherosclerotic disease within the lower extremities. The presentation of PAD is diverse ranging from asymptomatic disease to claudication or to debilitating rest pain, nonhealing ulcers, and gangrene. PAD is associated with significant morbidity, mortality, and healthcare costs. Proper diagnosis and management of PAD is important so as to maintain quality of life and reduce the risk of cardiovascular disease and adverse limb events such as amputation. This document provides a comprehensive outpatient approach to the clinical assessment of PAD that includes risk factors, diagnosis, treatment, and follow-up options.

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.

Angiosome Specific Revascularisation: Does the Evidence Support It?

OBJECTIVE

To explain the angiosome concept and explore the practical application of the angiosome literature to a clinical scenario, in this case a tibial angioplasty for critical ischaemia.

METHODS

Clinical vignette with explanation of the decisions made and subsequent clinical results based on the theory of the angiosome concept and the literature on angiosomal revascularisation; in this case the results of our group's recent update to a systematic review and meta-analysis.

RESULTS

Endovascular combined or direct angiosomal revascularisation if superior to indirect revascularisation. This was borne out in the clinical scenario, where an indirect peroneal reperfusion of the AT angiosome resulted in major amputation. Open surgery is less dependent on the angiosome concept. The presence of adequate collateralisation into a foot arch seems to be the most important factor predicting success of indirect revascularisation. The evidence for both suffers from selection bias and many of the findings in the literature are wholly due to selection bias.

CONCLUSION

The angiosome concept is useful during both open and endovascular tibial revascularisation. However, the runoff in the foot is critical to success and may not follow the 'classic' angiosome model in diabetes.

The Society for Vascular Surgery Wound, Ischemia, and foot Infection (WIfI) classification system predicts wound healing better than direct angiosome perfusion in diabetic foot wounds

OBJECTIVE

Previous studies show conflicting results in wound healing outcomes based on angiosome direct perfusion (DP), but few have adjusted for wound characteristics in their analyses. We have previously shown that the Society for Vascular Surgery Wound, Ischemia, and foot Infection (WIfI) classification correlates with wound healing in diabetic foot ulcers (DFUs) treated by a multidisciplinary team. The aim of this study was to compare WIfI classification vs DP and pedal arch patency as predictors of wound healing in patients presenting with DFU and peripheral arterial disease.

METHODS

We performed a retrospective review of a prospectively maintained database of all patients with peripheral arterial disease presenting to our multidisciplinary DFU clinic who underwent angiography. An angiosome was considered directly perfused if the artery feeding the angiosome was revascularized or was completely patent. Wound healing time at 1 year was compared on the basis of DP vs indirect perfusion, Rutherford pedal arch grade, and WIfI classification using univariable statistics and Cox proportional hazards models.

RESULTS

Angiography was performed on 225 wounds in 99 patients (mean age, 63.3 ± 1.2 years; 62.6% male; 53.5% black) during the entire study period. There were 33 WIfI stage 1, 33 stage 2, 51 stage 3, and 108 stage 4 wounds. DP was achieved in 154 wounds (68.4%) and indirect perfusion in 71 wounds (31.6%). On univariable analysis, WIfI classification was significantly associated with improved wound healing (57.2% for WIfI 3/4 vs 77.3% for WIfI 1/2; P = .02), whereas DP and pedal arch patency were not (both, P ≥ .08). After adjusting for baseline patient and wound characteristics, WIfI stage remained independently predictive of wound healing (WIfI 3/4: hazard ratio [HR], 0.77; 95% confidence interval [CI], 0.67-0.88), whereas DP (HR, 0.82; 95% CI, 0.55-1.21) and pedal arch grade (HR, 0.85; 95% CI, 0.70-1.03) were not.

CONCLUSIONS

In our population of patients treated by a multidisciplinary diabetic foot service, the Society for Vascular Surgery WIfI classification system was a stronger predictor of diabetic foot wound healing than DP or pedal arch patency. Our results suggest that a measure of wound severity should be included in all future studies assessing wound healing as an outcome, as differences in patients' wound characteristics may be a strong contributor to the variation of angiosome-directed perfusion results previously observed.

BAD transmission and SAD distribution: a new scenario for critical limb ischemia

BACKGROUND

Most of the studies on peripheral artery disease (PAD) focused on above-the-ankle artery disease, while less is known about foot artery disease. We hypothesize a scenario were two different diseases can be present in PAD patients, big artery disease (BAD) and small artery disease (SAD), overlapping at the foot level; the aim of this study is to evaluate their prevalence and their correlation with risk factors and critical limb ischemia (CLI) in a large cohort of patients with symptomatic PAD.

METHODS

We retrospectively reviewed 1915 limbs of 1613 patients (502 females, mean age 72.4±10.8 years) who underwent angiography between September 2009 and November 2013. Age, sex, diabetes, smoke history, high blood pressure, dialysis and BMI were considered as risk factors. Logistic regression was performed to test the association of arterial lesions patterns and CLI, and to evaluate the association between risk factors and lesion localization.

RESULTS

SAD was present in 414 patients (25.2%). Patients with disease of any of plantar, dorsalis pedis arteries and SAD faced higher risk of CLI (OR=13.25, 95% CI: 1.69-104.16). SAD was associated with diabetes and dialysis (both: OR=4.85; dialysis only: OR=3.60; diabetes only: OR=1.70; none: reference OR; P<0.01), weight (underweight: OR=1.10; normal: reference OR; overweight: OR=0.81; obese: OR=0.60; P=0.03), while women and tobacco smokers were less likely to have SAD (women: OR=0.68; P<0.01; tobacco use: OR=0.54; P<0.01).

CONCLUSIONS

SAD was strongly and independently associated with CLI, diabetes and dialysis. Thus, SAD should be regarded as a leading actor in CLI.

Pilot Assessment of the Angiosome Concept by Intra-operative Fluorescence Angiography After Tibial Bypass Surgery

OBJECTIVES

The "angiosome" concept as a model for decision making in revascularisation of patients with critical limb ischaemia (CLI) has been subject to lively discussion in recent years. The aim of this prospective pilot study was to use intra-operative fluorescence angiography to provide further data on the angiosome concept on the level of microcirculation after tibial bypass surgery.

DESIGN, MATERIALS, AND METHODS

This was a prospective analysis of 40 patients presenting with CLI Rutherford stage IV to VI before and after tibial bypass surgery. The macrocirculation was measured by the ankle brachial index. Skin microcirculation was assessed by intra-operative fluorescence angiography. The alteration of microcirculation was compared in direct and indirect revascularised angiosomes. Clinical follow-up investigations were performed and the wound healing rate was compared between the different revascularisation methods.

RESULTS

Cumulated microcirculation parameters showed a significant improvement after surgery (ingress, ingress rate p<.001). Likewise, general microcirculatory improvement was observed in each foot angiosome after revascularisation, regardless of the tibial artery revascularised. Furthermore, a comparison of the direct (DR) and the indirect revascularised (IR) angiosomes did not show a significant difference concerning the improvement of microcirculation (difference DR-IR, ingress: 1.69, 95% CI 71.73-75.11; ingress rate: 0.08, 95% CI -12.91 to 13.07). The wound healing rate was similar in both groups, although the time to wound healing was faster by on average 2.5 months in the DR group (p=.083).

CONCLUSION

Microcirculatory improvement was seen over the whole foot after tibial bypass. Therefore, fluorescence angiography is a promising tool to evaluate the angiosome concept in future larger studies. Clinicaltrials.gov: NCT03012750.

The comparative efficacy of angiosome-directed and indirect revascularisation strategies to aid healing of chronic foot wounds in patients with co-morbid diabetes mellitus and critical limb ischaemia: a literature review

BACKGROUND

Ischaemic ulcerations have been reported to persist and/or deteriorate despite technically successful revascularisations; a higher incidence of which affects patients with diabetes and critical limb ischaemia. In the context of wound healing, it is unclear if applications of the angiosome concept in 'direct revascularisation' (DR) would be able to aid the healing of chronic foot ulcerations better than the current 'best vessel' or 'indirect revascularisation' (IR) strategy in patients with co-morbid diabetes and critical limb ischaemia.

METHODS

A literature search was conducted in eight electronic databases, namely AMED, CINAHL, The Cochrane Library, ProQuest Health & Medicine Complete, ProQuest Nursing & Allied Health Source, PubMed, ScienceDirect and TRIP database. Articles were initially screened against a pre-established inclusion and exclusion criteria to determine eligibility and subsequently appraised using the Newcastle-Ottawa Scale.

RESULTS

Five retrospective studies of varying methodological quality were eligible for inclusion in this review. Critical analysis of an aggregated population (n = 280) from methodologically stronger studies indicates better wound healing outcomes in subjects who had undergone DR as compared to IR (p < 0.001; p = 0.04). DR also appears to result in a nearly twofold increase in probability of wound healing within 12 months (hazard ratio, 1.97; 95% CI, 1.34-2.90). This suggests that achieving direct arterial perfusion to the site of ulceration may be important for the healing of chronic diabetic foot ulcerations.

CONCLUSION

Incorporating an angiosome-directed approach in the lower limb revascularisation strategy could be a very useful adjunct to a solely indirect approach, which could increase the likelihood of wound healing. With the limited data currently available, findings appear promising and merit from further investigation. Additional research to form a solid evidence base for this revised strategy in patients with co-morbid diabetes and critical limb ischaemia is warranted.

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.

Percutaneous Therapies for Peripheral Artery Disease

Percutaneous therapies for peripheral artery disease continue to evolve with new techniques and devices. Although guidelines-recommended therapies have impacted cardiovascular morbidity and mortality, endovascular interventions have been shown to reduce limb pain, improve quality of life, and prolong walking distance for those with claudication and to reduce amputation rates among those with critical limb ischemia. Novel devices such as drug-eluting stents and drug-coated balloons have improved patency for moderate-length lesions, whereas others allow treatment of heavily calcified and tortuous segments. New adjunctive devices to cross lesions and reduce or modify associated plaque have also been developed, although level 1 data regarding their efficacy are sparse. There has also been a better mechanistic understanding of lower extremity endovascular treatment using tools such as intravascular ultrasound. This information has highlighted the need for better stent size selection for the femoropopliteal arterial segments and larger balloon diameters for the tibial arteries. Moreover, a wound perfusion approach with direct in-line flow, the so-called angiosome approach, and reconstruction of the pedal loop have been advocated for improved wound healing. Technical advances such as the tibiopedal access and reentry methods have allowed crossing of lesions that were considered no option for the endovascular approach in the past. Collectively, there has been increased awareness, interest, and commitment by various specialty societies and organizations to advance the treatment of peripheral artery disease and critical limb ischemia. This is also evident by the recent coalition of 7 professional societies and organizations that represented >150 000 allied health professionals and millions of patients with peripheral artery disease at the 2015 Centers for Medicaid and Medicare Services Medicare Evidence Development and Coverage Analysis Committee meeting. The percutaneous therapies for peripheral artery disease continue to evolve with longer follow-up with randomized data and larger prospective registries. In the future, it is hopeful that we will treat the lower extremity arteries according to segments, taking into account plaque morphology, luminal versus subintimal crossing, location, and stenotic versus occlusive disease. Until then, we must identify the most cost-effective, efficacious, and safe treatment for each patient. The goal of this article is to aid the practicing vascular specialist consider the optimal choices for the management of patients with vascular disease.

Prevalence of Tibial Artery and Pedal Arch Patency by Angiography in Patients With Critical Limb Ischemia and Noncompressible Ankle Brachial Index

Background—

Approximately 20% of patients undergoing ankle brachial index testing for critical limb ischemia have noncompressible vessels because of tibial artery calcification. This represents a clinical challenge in determining tibial artery patency. We sought to identify the prevalence of tibial artery and pedal arch patency by angiography in these patients.

Methods and Results—

One hundred twenty-five limbs (of 89 patients) with critical limb ischemia and ankle brachial index ≥1.4 who underwent lower extremity angiograms within 1 year were included. Reviewers of angiography were blinded to results of physiological testing. Tibial artery vessels were classified as completely occluded, significantly stenosed (≥50%), or patent (<50% stenosis). The sensitivity of toe brachial index and pulse volume recording to predict tibial artery disease was also determined. Of 125 limbs with noncompressible ankle brachial index, 72 (57.6%) anterior tibial and 80 (64%) posterior tibial arteries were occluded. Another 23 (18.4%) anterior tibial and 13 (10.4%) posterior tibial arteries had ≥50% stenosis. Pulse volume recording was moderate to severely dampened in 54 of 119 (45.4%) limbs. Toe brachial index <0.7 was found in 75 of 83 (90.4%) limbs. Moderate to severe pulse volume recording dampening was 43.6% sensitive, whereas toe brachial index <0.7 was 89.7% sensitive in diagnosing occluded or significantly stenotic tibial artery disease. The pedal arch was absent or incomplete in 86 of 103 (83.5%) limbs.

Conclusions—

Among patients with critical limb ischemia and noncompressible ankle brachial index results, the prevalence of occlusive tibial and pedal arch disease is very high. Toe brachial index <0.7 is more sensitive in diagnosing occluded and significantly stenotic tibial artery disease in these patients compared with ankle pulse volume recording.