Impact of Pedal Arch Patency on Tissue Loss and Time to Healing in Diabetic Patients with Foot Wounds Undergoing Infrainguinal Endovascular Revascularization

Clinical efficacy of endovascular revascularization combined with vacuum-assisted closure for the treatment of diabetic foot

BACKGROUND

The diabetic foot is a common cause of disability and death, and comorbid foot infections usually lead to prolonged hospitalization, high healthcare costs, and a significant increase in amputation rates. And most diabetic foot trauma is complicated by lower extremity arteriopathy, which becomes an independent risk factor for major amputation in diabetic foot patients.

AIM

To establish the efficacy and safety of endovascular revascularization (ER) combined with vacuum-assisted closure (VAC) for the treatment of diabetic foot.

METHODS

Clinical data were collected from 40 patients with diabetic foot admitted to the Second Affiliated Hospital of Soochow University from April 2018 to April 2022. Diabetic foot lesions were graded according to Wagner’s classification, and blood flow to the lower extremity was evaluated using the ankle-brachial index test and computerized tomography angiography of the lower extremity arteries. Continuous subcutaneous insulin infusion pumps were used to achieve glycemic control. Lower limb revascularization was facilitated by percutaneous tran-sluminal balloon angioplasty (BA) or stenting. Wounds were cleaned by nibbling debridement. Wound granulation tissue growth was induced by VAC, and wound repair was performed by skin grafting or skin flap transplantation.

RESULTS

Of the 35 cases treated with lower limb revascularization, 34 were successful with a revascularization success rate of 97%. Of these, 6 cases underwent stenting after BA of the superficial femoral artery, and 1 received popliteal artery stent implantation. In the 25 cases treated with infrapopliteal artery revascularization, 39 arteries were reconstructed, 7 of which were treated by drug-coated BA and the remaining 32 with plain old BA. VAC was performed in 32 wounds. Twenty-four cases of skin grafting and 2 cases of skin flap transplantation were performed. Two patients underwent major amputations, whereas 17 had minor amputations, accounting for a success limb salvage rate of 95%.

CONCLUSION

ER in combination with VAC is a safe and effective treatment for diabetic foot that can significantly improve limb salvage rates. The use of VAC after ER simplifies and facilitates wound repair.

In the Loop: Endovascular Pedal Arch Revascularization

Advanced endovascular techniques are increasingly being utilized to treat patients with peripheral arterial disease and chronic limb-threatening ischemia to improve lower extremity arterial perfusion. In diabetic patients, pedal arch patency has been associated with improved wound healing, limb salvage, and overall survival. Pedal-plantar loop revascularization is a technique that can restore arterial inflow between the dorsal and plantar arteries of the foot. This article will describe the inframallelolar arterial anatomy and focus on imaging, percutaneous endovascular techniques, and clinical study outcomes of pedal artery interventions.

Successful Revascularization, Angiosome Concept, and Multivessel Revascularization: Effects on Wound Healing: An Asian Perspective

Endovascular treatment for revascularization in patients with chronic limb-threatening ischemia (CLTI), which is commonly found in patients with diabetes mellitus demonstrates a variable result of vessel patency, wound healing rate, and limb salvage rate. The angiosome concept has been adopted to determine the best target arterial path (TAP) for revascularization for wound healing in CLTI patients. Recent publications demonstrated the benefit of angiosome-targeted revascularization to guide the endovascular treatment in patients CLTI. The best TAP under angiosome concept by direct revascularization with at least 2 of 3 below-the-knee arteries runoff to restore in-line pulsatile blood flow to the ischemic tissue shows the best patency and high rate of wound healing. However, the clinical evidence and application of the angiosome concept in daily practice are difficult and not well established. The vascular territories, collateral vessel, wound area, and locations which associated with angiosome are varied. This article review aims to summarize the concept of angiosome-targeted revascularization and multivessel revascularization for application to the real-world practice under the evidence-based data.

Proximal Arterial Inflow Revascularization Improves Pedal Arch Quality and Its Impact on Ischemic Diabetic Foot Ulcer Healing

BACKGROUND

Arterial perfusion is a key factor in diabetic foot ulcer (DFU) healing. Although it is associated with pedal arch patency, not all patients are amenable to pedal artery angioplasty. This study aims to determine the impact of angiographic improvement of the pedal arch quality after proximal arterial inflow revascularization (PAIR) and its association with wound healing.

METHODS

One hundred and fifty diabetic patients with tissue loss in 163 limbs who had digital subtraction angiography were studied. Cox regression analysis was used to determine independent predictors of wound healing. Wound healing rates in association with pedal arch patency were calculated by Kaplan-Meier analysis.

RESULTS

End-stage renal disease, minor amputation, and complete pedal arch patency were significant independent predictors of wound healing following PAIR with hazard ratios for failure: 3.02 (P = 0.008), 0.54 (P = 0.023), and 0.40 (P = 0.039), respectively. The prevalence of complete pedal arches increased by 24.1% with successful intervention (P < 0.001). The overall rates of wound healing at 6, 12, and 24 months were 36%, 64%, and 72%, respectively. The wound healing rate at 1 year in patients with a complete pedal arch was 73% compared to 45% in those with an absent pedal arch (P = 0.017).

CONCLUSIONS

PAIR increases complete pedal arch patency, a significant predictor of wound healing in DFU.

Validity of the Global Vascular Guidelines in Predicting Outcomes Based on First-Time Revascularization Strategy

BACKGROUND

The Global Vascular Guidelines (GVG) recommend selecting an endovascular versus open-surgical approach to revascularization for chronic limb-threatening ischemia (CLTI), based on the Global Limb Anatomic Staging System (GLASS) and wound, ischemia, and foot infection (WIfI) classification systems. We assessed the utility of GVG-recommended strategies in predicting clinical outcomes.

METHODS

We conducted a single-center, retrospective review of first-time lower-extremity revascularizations within a comprehensive limb-preservation program from 2010 to 2018. Procedures were stratified by (1) treatment concordance with GVG-recommended strategy (concordant versus nonconcordant groups), (2) GLASS stages I-III, and (3) endovascular versus open strategies. The primary outcome was 5-year freedom from major adverse limb events (FF-MALE), defined as freedom from reintervention or major amputation, and secondary outcomes included 5-year overall survival, freedom from major amputation, freedom from reintervention, and immediate technical failure (ITF) during initial revascularization. Kaplan-Meier (KM) survival analysis and multivariate analysis with Cox proportional hazard models were performed on the primary and secondary outcomes.

RESULTS

Of 281 first-time revascularizations for CLTI, 251 (89.3%) were endovascular and 186 (66.2%) were in the concordant group, with a mean clinical follow-up of 3.02 ± 2.40 years. Within the concordant group alone, 167 (89.8%) of revascularizations were endovascular. The concordant group had a higher rate of chronic kidney disease (60.8% vs. 45.3%, P = 0.02), WIfI foot infection grade (0.81 ± 1.1 vs. 0.56 ± 0.80, P = 0.03), and WIfI stage (3.1 ± 0.79 vs. 2.8 ± 1.2, P < 0.01) compared to the non-concordant group. After both KM and multivariate analyses, there were no significant differences in 5-year FF-MALE or overall survival between concordant and non-concordant groups. There was higher freedom from major amputation in the non-concordant group on KM analysis (83.9% vs. 74.2%, P = 0.025), though this difference was non-significant on multivariate analysis (hazard ratio [HR]: 0.49, 95% confidence interval [CI]: 0.21-1.15, P = 0.10). The open group had lower MALE compared to the endovascular group (HR: 0.39, 95% CI: 0.17-0.91, P = 0.029) attributed to a lower reintervention rate in the open group (HR: 0.31, 95% CI: 0.11-0.87, P = 0.026). GLASS stage was not associated with significant differences in outcomes, but the severity of GLASS stage was associated with ITF (2.1% in stage 1, 6.4% in stage 2, and 11.7% in stage 3, P = 0.01).

CONCLUSIONS

In this study, CLTI treatment outcomes did not differ significantly based on whether treatment was received in concordance with GVG-recommended strategy. There was no difference in overall survival between the endovascular and open groups, though there was a higher reintervention rate in the endovascular group. The GVG guidelines are an important resource to help guide the management of CLTI patients. However, in this study, both concordance with GVG guidelines and GLASS staging were found to be indeterminate in differentiating outcomes between complex CLTI patients treated primarily with an endovascular-first approach. The revascularization approach for a CLTI patient is a nuanced decision that must take into account patient anatomy and clinical status, as well as physician skill and experience and institutional resources.

Advanced Endovascular Techniques for Limb Salvage

As the number of patients affected by peripheral arterial disease continues to increase, new technical approaches and devices have been developed to provide effective and durable treatment options that will lead to improved outcomes. While the mainstay of endovascular intervention remains mostly balloon-based, several innovative techniques and technologies are in development that may provide new solutions. This review highlights recent endovascular advancements in the management of chronic limb-threatening ischemia and additional adjunctive devices that are needed to improve lesion patency, reduce the need for reintervention, and lead to better patient-centered functional outcomes.

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.

Non-reversed bifurcated vein graft improves time to healing in ischemic patients undergoing lower limb distal bypass

BACKGROUND

Bifurcated vein grafts have been described in reconstructive microsurgery. No comparative studies have been published in lower limb arterial revascularization. The aim of this study was to compare non-reversed bifurcated vs. single vein graft in patients with critical limb-threatening ischemia (CLTI) undergoing lower limb distal bypass.

METHODS

Between January 2015 and December 2021 193 CLTI patients have been treated at our center with vein bypass, and distal anastomosis on infrapopliteal vessels; 137 patients (71%) received a single graft (Group SIN), and 56 patients (29%) had a bifurcated bypass (Group BIF). Primary outcomes measures were time to healing, primary patency, primary assisted patency, secondary patency, and limb salvage. Two-year outcomes according to Kaplan-Meier curves were evaluated and compared.

RESULTS

Both groups were homogeneous in terms of demographic data, preoperative risk factors, and clinical presentation except for an elderly age in Group BIF (77.5 vs. 71.5 years; P<0.001). Intraoperative technical success was achieved in all patients. Overall median duration of follow-up was 19 months (interquartile range 9-36). Wound healing did not differ between the two groups (77.4% Group SIN vs. 73.2% Group BIF; P=0.33). Mean time to healing was faster in Group BIF (2.4 vs. 6.8 months; P<0.001). At 2-year follow-up there were no differences between the two groups in terms of primary patency (71.4% Group SIN vs. 54% Group BIF; P=0.10), primary assisted patency (81.7% Group SIN vs. 76.4% Group BIF; P=0.53), secondary patency (85.1% Group SIN vs. 80.9% Group BIF; P=0.79), and limb salvage (92.3% Group SIN vs. 87.2% Group BIF; P=0.64).

CONCLUSIONS

Bifurcated graft improved time to healing in CLTI patients undergoing infrapopliteal non-reversed vein bypass. Two-year overall patencies and limb salvage did not differ accordingly to vein graft configuration (single vs. bifurcated).

The Relationship Between the Global Limb Anatomic Staging System Inframalleolar Modifier and the Outcomes of Diabetic Foot Ulcer with Peripheral Artery Disease

BACKGROUND

We aimed to investigate the relationship between the condition of the inframalleolar (IM) arteries, as assessed by the Global Limb Anatomic Staging System Inframalleolar (GLASS IM) modifier, and the outcomes of patients with diabetic foot ulcers.

METHODS

The data of 215 patients, who underwent endovascular therapy from January 2016 to May 2020 at our center, were retrospectively reviewed. Patients were divided into the P0, P1, and P2 groups according to the angiography results. The rates of ulcer healing, limb salvage, survival, and amputation-free survival were compared during the 2-year period after discharge.

RESULTS

Of the 216 affected limbs, 35 (16%) were classed as P0, 122 (57%) as P1, and 59 (27%) as P2. Compared with the P2 group, the P0 + P1 group had a higher ulcer healing rate (P = 0.001), a shorter ulcer healing time (P = 0.004), and a higher survival rate (P = 0.044). GLASS IM Modifier classification P2 was an independent predictor of nonhealing ulcers. No significant difference was observed between the P0 versus P1 groups.

CONCLUSIONS

GLASS IM modifier classification P2 is an independent risk factor for a poor outcome. GLASS IM modifier classification P0 versus P1 demonstrates similar outcomes to each other.

Pedal arterial calcification score is associated with the risk of major amputation in chronic limb-threatening ischemia

OBJECTIVE

The medial arterial calcification (MAC) score is a simple metric that describes the burden of inframalleolar calcification using a plain foot radiograph. We hypothesized that a higher MAC score would be independently associated with the risk of major amputation in patients with chronic limb-threatening ischemia (CLTI).

METHODS

We performed a single-institution, retrospective study of 250 patients who had undergone infrainguinal revascularization for CLTI from January 2011 to July 2019 and had foot radiographs available for MAC score calculation. A single blinded reviewer assigned MAC scores of 0 to 5 using two-view minimum plain foot radiographs, with 1 point each for calcification of >2 cm in the dorsalis pedis, plantar, and metatarsal arteries and >1 cm in the hallux and non-hallux digital arteries.

RESULTS

The MAC score was 0 in 36%, 1 in 5.2%, 2 in 8.4%, 3 in 14%, 4 in 14%, and 5 in 21%. The MAC score was trichotomized to facilitate analysis and clinical utility (mild, MAC score 0-1; moderate, MAC score 2-4; and severe, MAC score 5). The variables independently associated with a higher MAC score were male sex, diabetes, end-stage renal disease, and the global limb anatomic staging system pedal score. The MAC score was not associated with the Society for Vascular Surgery WIfI (wound, ischemia, foot infection) grade or overall WIfI stage (P = .58). The median follow-up was 759 days (interquartile range, 264-1541 days). A higher MAC score was significantly associated with the risk of major amputation (P < .0001). In a Cox proportional hazards multiple regression model for major amputation that included the trichotomized MAC score, diabetes, end-stage renal disease, and WIfI stage (1-3 vs 4). The MAC score (MAC score 5: hazard ratio [HR], 4.9; 95% confidence interval [CI], 1.9-13.1; P = .001; MAC score 2-4: HR, 3.4; 95% CI, 1.3-8.8; P = .01) and WIfI stage (WIfI stage 4: HR, 2.1; 95% CI, 1.1-3.9; P = .03) were significantly associated with the risk of major amputation. In the subsets of patients with the most advanced WIfI stage of 3 to 4 (191 of 250; 76%) and patients with diabetes (185 of 250; 74%), the MAC score further stratified the risk of major amputation on univariate and multivariate analyses.

CONCLUSIONS

The MAC score is a simple, practical tool and a strong independent predictor of major amputation in patients with CLTI. It provides novel clinical data that are currently unmeasured using any validated CLTI staging system. The MAC score is a promising standardized measure of inframalleolar disease burden that can be used in conjunction with the WIfI staging system to help improve outcomes stratification and determine the optimal treatment strategies for patients with CLTI.

Influence of pedal arch quality on 5-year survival and limb salvage in patients with diabetic foot ulcers undergoing peripheral angiography

INTRODUCTION

The aim of this study was to evaluate the influence of pedal arch quality on 5-year survival and limb salvage in diabetic patients with foot wounds undergoing peripheral angiography.

METHODS

Between January 2014 and December 2014, 153 diabetic patients with foot wounds underwent peripheral angiography. Final foot angiograms were used to allocate patients according to pedal arch: complete pedal arch (CPA), incomplete pedal arch (IPA), and absent pedal arch (APA). Five-year survival and limb salvage rates were analyzed with Kaplan-Meier curves and compared by means of Gehan-Breslow-Wilcoxon test. Associations of patient and procedure variables with overall survival and limb salvage outcomes were sought with univariate and multivariate analyses.

RESULTS

A below-the-knee (BTK) artery was the target vessel in 80 cases (52.3%). Five-year Kaplan-Meier rates of survival were similar in all groups (p = 0.1): CPA 30%, IPA 27.5%, and APA 26.4%. Five-year limb salvage rates were significantly better in patients with CPA/IPA (p < 0.001): CPA 95.1%, IPA 94.3%, and APA 67.3%. In the whole population study, multivariate analysis showed significant association of smoking (p = 0.01), chronic renal failure (p = 0.02), and severity of foot wounds (p < 0.001) with survival. Coronary artery disease (p = 0.03), severity of foot wounds (p = 0.001), and pedal arch status (p = 0.05) showed strong association with limb salvage.

CONCLUSIONS

Pedal arch quality significantly affected limb salvage but not survival at 5 years in patients with diabetic foot ulcers. Smoking, chronic renal failure, and severity of foot wounds affected overall survival, whilst coronary artery disease, and severity of foot wounds limb salvage.

Successful Revascularization of Infrapopliteal Chronic Total Occlusions Using the Plantar Arch as a Conduit and Retrograde Pedal Access

Background: With the rising prevalence of critical limb ischemia (CLI), the pedal-plantar loop technique and retrograde access may be needed to increase interventional success.

Case Report: A 63-year-old female with severe peripheral artery disease presented with a 2-month nonhealing wound on the dorsum of her left foot despite wound care. We inserted a 65-cm Destination Guiding Sheath and crossed the right superficial femoral artery (SFA) chronic total occlusion (CTO) that we initially treated with a 4.0-mm Ultraverse balloon. We attempted unsuccessfully to cross the distal anterior tibial artery into the dorsalis pedis artery. We obtained antegrade access of the posterior tibial artery at the level of the ankle with a 2.9-French Cook pedal access kit. We inserted a 90-cm CXI catheter with a 0.014 Fielder XT wire and used the lateral plantar artery as a conduit to cross the dorsalis pedis artery and distal anterior tibial artery CTO with retrograde wire manipulation via lateral plantar artery. Finally, we performed distal anterior tibial and dorsalis pedis CTO balloon angioplasty with a 2.5 × 220-mm Ultraverse balloon and performed SFA percutaneous transluminal angioplasty and stenting with a 7.0 × 120-mm Zilver PTX stent, postdilated with a 6.0-mm Ultraverse balloon. We successfully established in-line flow to the foot with 3-vessel runoff. The patient's wound healed in a month.

Conclusion: Retrograde pedal access can improve the success rate of recanalization of below-the-knee disease in patients with CLI.

Indirect Endovascular Revascularization via Collaterals: A New Classification to Predict Wound Healing and Limb Salvage

BACKGROUND

In the setting of chronic limb ischemia, lower extremity (LE) wounds require revascularization of source arteries for wound healing and limb salvage. Direct revascularization of the source artery is preferred but cannot always be performed. Our objective was to analyze the influence of arterial-arterial connections on clinical outcomes after angiosome-directed endovascular revascularization.

METHODS

Consecutive LE wounds in patients with isolated infra-popliteal disease revascularized endovascularly from 2012 to 2016 within a single center were retrospectively reviewed. Treatment was classified as direct revascularization (DR) if the source artery supplying the wound angiosome was treated, indirect revascularization via collaterals (IR-C) if the source artery angiosome was revascularized by another major artery via arterial connections, or indirect revascularization (IR) if direct revascularization of the source artery angiosome was not possible. Demographics, comorbidities, and patient outcomes were collected.

RESULTS

Of 105 patients with 106 LE wounds, there were 35, 38, and 33 patients in the DR, IR-C, and IR groups, respectively. The mean age was 65.8 years old (standard deviation (SD) 11.9) with 81 males (77.1%) and 24 females (22.9%). Average follow-up was 21.0 months (SD 14.0). Overall wound healing rates were 80.0%, 92.1%, and 63.6% for DR, IR-C, and IR, respectively (P = 0.009). Significant differences were found between all 3 group comparisons, DR versus IR-C (P = 0.010), DR versus IR (P = 0.013), IR-C versus IR (P = 0.008). Overall major amputation-free survival was 85.7%, 89.5%, and 69.7% in DR, IR-C, and IR groups, respectively, with statistically significant differences between the IR-C and IR groups (P = 0.036).

CONCLUSIONS

Treating diseased infra-popliteal arteries and improving blood flow via arterial-arterial connections as per the angiosome model improved wound healing and amputation-free survival in this cohort. Although DR is still the gold standard, revascularization using IR-C may give superior healing results even in highly comorbid patients. This offers an additional avenue for treatment, especially when DR is not possible.

GLASS (Global Limb Anatomic Staging System): a critical appraisal

BACKGROUND

THE Global Vascular Guidelines (GVGs) propose a new Global Anatomic Staging System (GLASS) resulting in three stages of complexity for intervention. The aim of this study was to retrospectively classify a large cohort of CLTI patients according to the GLASS, evaluating its distribution in a real-world setting.

METHODS

Retrospective, single center, observational study enrolling all consecutive CLTI patients submitted to infra-inguinal endovascular revascularization in our institution, between June 2014 and September 2019. Patients were categorized according to the GLASS for femoro-popliteal (FP), infra-popliteal (IP) and infra-malleolar grading. FP and IP grades were merged to get the final GLASS stage for each limb.

RESULTS

The study included 1995 CLTI patients who underwent 2850 endovascular procedures in which 6009 arterial lesions were successfully treated. The FP segment was classified as: 1292 (45.3%) grade 0, 475 (16.6%) grade 1, 159 (5.6%) grade 2, 209 (7.4%) grade 3, and 715 (25.1%) grade 4. The IP segment was classified as: 1529 (53.6%) grade 0, 183 (6.4%) grade 1, 80 (2.8%) grade 2, 207 (7.3%) grade 3, and 851 (29.9%) grade 4. The combination of FP and IP grading led to GLASS stages: 922 (32.3%) stage 1, 375 (13.2%) stage 2, 1472 (51.6%) stage 3.

CONCLUSIONS

The distribution of the FP, IP and final GLASS grading was mainly grouped at the two extremes, letting the intermediate grades rather scarce. The majority of patients present with an absent or severely diseased pedal arch, stressing the need to incorporate infra-malleolar disease into the GLASS.

A Novel Scoring System for Small Artery Disease and Medial Arterial Calcification Is Strongly Associated With Major Adverse Limb Events in Patients With Chronic Limb-Threatening Ischemia

Purpose:

To evaluate the roles of small artery disease (SAD) and medial arterial calcification (MAC) in patients with chronic limb-threatening ischemia (CLTI) and to identify any correlation between these factors and peripheral artery disease (PAD) or outcomes after treatment.

Materials and Methods:

A retrospective review was conducted of 259 limbs with tissue loss among 223 CLTI patients (mean age 72.2±11.4 years; 194 men) having an angiographic foot vessel study, foot radiography, and at least 6 months of follow-up after intervention. SAD and MAC were quantified using a 3-level score (0=absent, 1=moderate, 2=severe) based on angiography for SAD and foot radiographs for MAC. The MAC score was validated and compared with the SAD score, evaluating their associations with PAD distribution and clinical outcomes.

Results:

Based on the MAC score, the 259 limbs were classified as 55 group 0 (21.2%), 89 group 1 (34.4%), and 115 group 2 (44.4%). The SAD score stratified the 259 limbs as 67 group 0 (25.9%), 76 group 1 (29.3%), and 116 group 2 (44.8%). Interobserver reproducibility of the MAC score was high (correlation coefficient 0.96). Sensitivity and specificity of the MAC score in detecting SAD was 100% and 98.1%, respectively, in SAD groups 0 and 2 vs 99.1% and 92.7%, respectively, for SAD group 1. PAD was more proximal in MAC and SAD groups 0 and more distal in groups 1 and 2. Both MAC and SAD scores were able to predict clinical endpoints. Multivariable analysis demonstrated that the MAC score represents an independent risk factor for adverse limb events.

Conclusion:

SAD and MAC must be considered expressions of the same obstructing disease, able to adversely impact the fate of CLTI patients. SAD and MAC scores are powerful prognostic indicators of major adverse limb events in CLTI patients.

A Review and Proposed Classification System for the No-Option Patient With Chronic Limb-Threatening Ischemia

A growing, but poorly defined subset of patients with chronic limb-threatening ischemia (CLTI) have "no option" for revascularization. One notable subgroup includes patients with severe ischemia and advanced pedal artery occlusive disease, termed "desert foot," who are at high risk for major amputation due to a lack of conventional revascularization options. Although new therapies are being developed for no-option patients with desert foot anatomy, this subgroup and the broader group of no-option patients are not well defined, limiting the ability to evaluate outcomes. Based on a systematic review, a classification of the no-option CLTI patient was constructed for use in clinical practice and studies. Several no-option conditions were identified, including type I-severe and pedal occlusive disease (desert foot anatomy) for which there is no accepted method of repair; type II-lack of suitable venous conduit for bypass in the setting of an acceptable target for bypass; type III-extensive tissue loss with exposure of vital structures that renders salvage impossible; type IV-advanced medical comorbidities for which available revascularization options would pose a prohibitive risk; and type V-presence of a nonfunctional limb. While type I and type II patients may have no option for revascularization, type III and type V patients have wounds, infection, comorbidities, or functional status that may leave them with few options for revascularization. As treatment strategies continue to evolve and novel methods of revascularization are developed, the ability to identify no-option patients in a standardized fashion will aid in treatment selection and assessment of outcomes.

2D perfusion DSA with an open-source, semi-automated, color-coded software for the quantification of foot perfusion following infrapopliteal angioplasty: a feasibility study

BACKGROUND

Foot perfusion has been recently implemented as a new tool for optimizing outcomes of peripheral endovascular procedures. A custom-made, two-dimensional perfusion digital subtraction angiography (PDSA) algorithm has been implemented to quantify outcomes of endovascular treatment of critical limb ischemia (CLI), assist intra-procedural decision-making, and enhance clinical outcomes.

METHODS

The study was approved by the Hospital's Ethics Committee. This prospective, single-center study included seven consecutive patients scheduled to undergo infrapopliteal endovascular treatment of CLI. Perfusion blood volume (PBV), mean transit time (MTT), and perfusion blood flow (PBF) maps were extracted by analyzing time-intensity curves and signal intensity on the perfused vessel mask. Mean values calculated from user-specified regions of interest (ROIs) on perfusion maps were employed to evaluate pre- and post-endovascular treatment condition. Measurements were performed immediately after final PDSA.

RESULTS

In total, five patients (aged 54 ± 16 years, mean ± standard deviation) were analyzed, as two patients were excluded due to significant motion artifacts. Post-procedural MTT presented a mean decrease of 19.1% for all patients and increased only in 1 of 5 patients, demonstrating in 4/5 patients an increase in tissue perfusion after revascularization. Overall mean PBF and PBV values were also analogously increased following revascularization (446% and 69.5% mean, respectively) and in the majority of selected ROIs (13/15 and 12/15 ROIs, respectively).

CONCLUSIONS

Quantification of infrapopliteal angioplasty outcomes using this newly proposed, custom-made, intra-procedural PDSA algorithm was performed using PBV, MTT, and PBF maps. Further studies are required to determine its role in peripheral endovascular procedures ( ClinicalTrials.gov Identifier: NCT04356092).

Digital Subtraction Angiography Prior to an Amputation for Critical Limb Ischemia (CLI): An Expert Recommendation Statement From the CLI Global Society to Optimize Limb Salvage

Despite recent guideline updates on peripheral artery disease (PAD) and critical limb ischemia (CLI) treatment, the optimal treatment for CLI is still being debated. As a result, care is inconsistent, with many CLI patients undergoing an amputation prior to what many consider to be mandatory: consultation with an interdisciplinary specialty care team and a comprehensive imaging assessment. More importantly, quality imaging is critical in CLI patients with below-the-knee disease. Therefore, the CLI Global Society has put forth an interdisciplinary expert recommendation for superselective digital subtraction angiography (DSA) that includes the ankle and foot in properly indicated CLI patients to optimize limb salvage. A recommended imaging algorithm for CLI patients is included.

New Innovations and Devices in the Management of Chronic Limb-Threatening Ischemia

As the number of patients afflicted by chronic limb-threatening ischemia (CLTI) continues to grow, new solutions are necessary to provide effective, durable treatment options that will lead to improved outcomes. The diagnosis of CLTI remains mostly clinical, and endovascular revascularization remains mostly balloon-based. Multiple innovative techniques and technologies are in development or in early usage that may provide new solutions. This review categorizes areas of advancement, highlights recent developments in the management of CLTI and looks forward to novel devices that are currently under investigation.

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.