Wound, Ischemia, Foot Infection Research Articles

Association Between the Society for Vascular Surgery (SVS)-WIfI (Wound, Ischemia, Foot Infection) Classification, Wagner-Meggitt Classification, and Amputation Rate in Patients With Diabetic Foot Infection.

Diabetic foot infection (DFI) is a common problem in patients with diabetic foot disease. Amputations and other complications of DFI lead to significant morbidity and mortality. The Society for Vascular Surgery (SVS)-WIfI (wound, ischemia, and foot infection) classification system can evaluate the benefit from revascularization and the risk of amputation in 1 and 3 years. We aimed to evaluate SVS-WIfI and Wagner-Meggitt (WM) prediction of DFI outcome, and to determine factors associated with major amputation and mortality rate. The patients with diabetes who presented between June 2018 and May 2020 with characteristics suggesting a more serious DFI or potential indications for hospitalization were reviewed in this cohort study. Demographic data, clinical characteristics, and type of revascularization were evaluated. One-year and 3-year amputation and mortality rates were the main outcomes. The grading of WM classification and the SVS-WIfI score were compared between amputation and nonamputation groups. Association between mortality and comorbidity were analyzed. One hundred and thirty-one patients admitted with DFI were included in study. And 73.28% had peripheral arterial disease (PAD). The 1-year and 3-year major amputation rates were 16.03% and 26.23%, respectively. Seventy-eight (59.54%) patients required minor amputation to control infection before revascularization. PAD (risk ratio [RR] 1.47: 95% confidence interval [CI] 1.29-1.67, P = .032), benefit from revascularization clinical stage 3 on SVS-WIfI score (RR 4.56: 95%CI 1.21-17.21, P = 0.007), and high WM classification score (RR 9.46: 95% CI 5.65-15.82, P < 0.001) were associated by multivariate analysis with high amputation rates. 1-year & 3-year amputation risk on SVS-WIfI score were not associated with amputation rates in DFI (P = .263 and .496). Only 9 (6.8%) patients were lost to follow up during the 3-year period. WM classification score, SVS-WIfI score on benefit from revascularization, and PAD were strongly associated with major amputation rates in patients with DFI.

The Wound Express System, A Potential Treatment for Patients with Ulcers and Non-Operable Arterial Disease: A Pilot Safety Study

Background: Intermittent pneumatic compression (IPC) devices apply intermittent compression to the thigh, which is thought to facilitate wound healing by improving wound perfusion in patients with chronic limb-threatening ischemia and no option for revascularization. Wound Express is an IPC device but its safety and efficacy are currently unclear. In this study, we aimed to determine the safety of the Wound Express IPC system in this high-risk cohort.Methods: This was a prospective, non-controlled, non-randomized pilot safety study. In total, 19 patients were screened for inclusion and 10 were recruited. IPC was applied for 2 hours per day for 12 weeks. The primary endpoint was any treatment-related adverse event in the first 3 months. Secondary endpoints included pain using the visual analogue scale, limb status assessed using the Wound, Ischemia, Foot Infection (WIFi) score and quality of life using the Vascular Quality of Life Questionnaire (VASUQOL) score.Results: Of the 10 patients who were enrolled, eight completed the 12-week course. There were no treatment-related adverse events. One patient died from coronavirus disease 19-related disease and two withdrew for reasons unrelated to treatment. Median pain scores were reduced from 6 to 0, while median VASUQOL increased from 10 to 16.5. WIFi scores were reduced in three out of eight of participants (37.5%).Conclusion: Wound Express appears to be safe and may decrease pain, improve wound healing and improve quality of life for chronic limb-threatening ischemia patients. Adequately powered, prospectively randomized trials of the Wound Express system to assess its efficacy and safety are warranted.

Adherence to vascular care guidelines for emergency revascularization of chronic limb-threatening ischemia

ObjectiveIn 2022, the National Health Service Commissioning for Quality and Innovation (CQUIN) indicator for vascular surgery, with its pay-for-performance incentive for timely (5-day) revascularization of chronic limb-threatening ischemia (CLTI), was introduced. We sought to assess its effects in terms of (1) changes in the care pathway process measures relating to timing and patient outcomes; and (2) adherence to the Peripheral Arterial Disease Quality Improvement Framework (PAD-QIF) guidelines for patients admitted with CLTI. MethodsA retrospective before-and-after cohort study was performed from January to June 2022 of nonelective admissions for CLTI who underwent revascularization (open, endovascular, or hybrid) at Cambridge University Hospitals National Health Service Foundation Trust, a regional vascular “hub.” The diagnostic and treatment pathway timing-related process measures recommended in the PAD-QIF were compared between two 3-month cohorts—before vs after introduction of the CQUIN. ResultsFor the two cohorts (before vs after CQUIN), 17 of 223 and 17 of 219 total admissions met the inclusion criteria, respectively. After introduction of financial incentives, the percentage of patients meeting the 5-day targets for revascularization increased from 41.2% to 58.8% (P = .049). Improvements were also realized in the attainment of PAD-QIF targets for a referral-to-admission time of ≤2 days (from 82.4% to 88.8%; P = .525) and admission-to-specialist-review time of ≤14 hours (from 58.8% to 76.5%; P = .139). An increase also occurred in the percentage of patients receiving imaging studies within 2 days of referral (from 58.8% to 70.6%; P = .324). The reasons for delay included operating list pressures and unsuitability for intervention (eg, active COVID-19 [coronavirus disease 2019] infection). No statistically significant changes to patient outcomes were observed between the two cohorts in terms of complications (pre-CQUIN, 23.5%; post-CQUIN, 41.2%; P = .086), length of stay (pre-QUIN, 12.0 ± 12.0 days; post-QUIN, 15.0 ± 21.0 days; P = .178), and in-hospital mortality (pre-QUIN, 0%; post-QUIN, 5.9%). Other PAD-QIF targets relating to delivery of care were poorly documented for both cohorts. These included documented staging of limb threat severity with the WIfI (wound, ischemia, foot infection) score (2.9% of patients; target >80%), documented shared decision-making (47.1%; target >80%), documented issuance of written information to patient (5.9%; target 100%), and geriatric assessment (6.3%; target >80%). ConclusionsThe pay-for-performance incentive CQUIN indicators appear to have raised the profile for the need for early revascularization to treat CLTI, engaging senior hospital management, and reducing the time to revascularization in our cohort. Further data collection is required to detect any resultant changes in patient outcomes. Documentation of guideline targets for delivery of care was often poor and should be improved.

Endovascular Revascularization and Outcomes of Critical Limb-Threatening Ischemia in Trinidad and Tobago: The EVENT Pilot Study-Challenges in a Limited-Resource, Caribbean Setting.

This retrospective study investigated major adverse limb events (MALE) and mortality outcomes in critical limb-threatening ischemia (CLTI) patients with tissue loss after an endovascular revascularization-first (EVR-1st) strategy. MALE and mortality were assessed in 157 consecutive patients with CLTI and tissue loss from June 2019 to June 2022 at the Eric Williams Medical Sciences Complex, Trinidad and Tobago. 157 patients underwent the EVR-1st strategy, of whom 20 were pivoted to immediate surgical revascularization (SR). Of the remaining 137 patients, successful EVR was achieved in 112, giving a procedural success of 82% and an all-comer overall success of 71%. The mortality and MALE rates were 2.7% and 8.9% at 2 years, respectively. Males and patients with previous major amputations were at significantly higher risk for MALE (p values of 0.016 and 0.018, respectively). There was a statistically significant difference in successful EVR for both Rutherford-Baker (RB) 5 (minor) and RB 6 (major) classifications: 63 (56%) vs. 5 (20%) and 49 (44%) vs. 20 (80%), both with a p value of 0.01. There were no differences in successful EVR amongst Wound, Ischemia, Foot Infection (WIfI) clinical stages. There were no differences in successful EVR amongst the Trans-Atlantic Inter-Society Consensus (TASC II) classifications. This study may prove clinically informative and applicable for an EVR-1st management strategy for high-risk patients with CLTI in a limited-resource, Caribbean setting. NCT05547022 (retrospectively registered).

A Novel Score Predicts Need of Open Revascularization Following Endovascular Revascularization in Patients with Infrainguinal Chronic Limb-threatening Ischemia

This study aims to assess the ability of a novel score, the infrainguinal successful endovascular treatment (iSET) score in predicting risk of open revascularization in patients undergoing endovascular revascularization (ER) for infrainguinal chronic limb-threatening ischemia (CLTI). A retrospective analysis of consecutive patients undergoing ER for CLTI between January 2015 and December 2018. The iSET is a score between 1 and 63. It combines components of the Global Vascular Guidelines evidence-based revascularization as follows: iSET = Wound, Ischemia, foot Infection (WIfI) × WIFI + inflow disease + 4 × Global limb anatomic staging system (GLASS) FP + 6 × GLASS IP + 3 × IM pedal modifier. It stratifies patients into low (0-21), moderate (22-42), and high (43-63). The primary outcome was freedom from open revascularization at 2 years. Secondary outcomes were 30-day and 1-year endovascular reintervention, major amputations (above the ankle joint), minor amputations (below the ankle joint) and mortality. Kaplan-Meier estimates and Cox proportional hazard model assessed ability of iSET to predict open revascularization risk. A P value < .05 was significant. The study included 159 limbs in 150 patients with 12% (n = 19), 53% (n = 84), and 35% (n = 56) having a low, moderate, and high iSET scores, respectively. Most patients presented with tissue loss (86%), WIfI stage 4 (64%), and GLASS III (47%). Patients with a high iSET were more likely to have received antibiotics prior to ER (odds ratio, 1.35; 95% confidence interval [CI], 1.08-1.70; P = .013) and less likely to have elective ER (odds ratio, 0.36; 95% CI, 0.18-0.72; P = .003). Most ER involved the femoropopliteal segment (84%), with 55% of these including concomitant infrapopliteal revascularization. Kaplan-Meier survival curves showed that 2-year freedom from open revascularization was 100%, 93%, and 79% with low, moderate, and high iSET, respectively (Fig). Mortality, reinterventions, and major amputations were similar at 30 days and 1 year (Table). There was an increase in minor amputations at 1 year with high iSET patients (38%; n = 20) compared with low (6%; n = 1) and moderate (21%; n = 15) iSET (P = .016). High iSET score predicted increased risk of open revascularization (hazard ratio, 4.75; 95% CI, 1.67-13.48; P = .003). The iSET is a novel comprehensive score incorporating guideline-driven parameters. The score correlated significantly with ER failure at 2 years with progressively lower freedom from open revascularization between low, moderate, and high iSET scores. Additionally, a high iSET score independently predicted subsequent open revascularization after ER. Further studies are needed to validate it as an adjunctive decision-making tool in patients with CLTI.TableThirty-day and 1-year outcomes in patients stratified by groupsOverallLowModerateHighP-value30-day Death2 (3)03 (2)2 (1).775 Endovascular reintervention8 (11)08 (6)10 (5).447 Major amputation2 (2)02 (1)3 (1).848 Minor amputation13 (18)6 (1)8 (6)21 (11).0861-year Death11 (15)013 (9)11 (6).334 Endovascular reintervention34 (48)31 (5)33 (24)37 (19).885 Major amputation13 (18)014 (10)15 (8).262 Minor amputation25 (36)6 (1)21 (15)38 (20).016Data is presented as percentage (number). Open table in a new tab

Relationship between WIfI (wound, ischemia, foot infection) stage and quality of life at revascularization in the BEST-CLI (best endovascular versus best surgical therapy in patients with chronic limb threatening ischemia) trial: Presented as an oral podium presentation at the Thirty-seventh Western Vascular Society Annual Meeting, Victoria, BC, Canada, September 17-20, 2022.

Relationship between WIfI (wound, ischemia, foot infection) stage and quality of life at revascularization in the BEST-CLI (best endovascular versus best surgical therapy in patients with chronic limb threatening ischemia) trial: Presented as an oral podium presentation at the Thirty-seventh Western Vascular Society Annual Meeting, Victoria, BC, Canada, September 17-20, 2022.

Presenting limb severity is associated with long-term outcomes after infrainguinal revascularization for chronic limb-threatening ischemia

ObjectiveThe SVS Wound, Ischemia, foot Infection (WIfI) limb staging system was established to estimate risk of major amputation in chronic limb-threatening ischemia (CLTI) and better stratify outcomes comparisons. There is little data on treatment outcomes beyond 1 year based on presenting WIfI stage. MethodsThis is a single-institution retrospective study of 413 patients who underwent infrainguinal revascularization for CLTI (2011-2021) with data available for WIfI staging. Patient characteristics and outcomes were gathered from the electronic medical record. Data were analyzed based on presenting WIfI stage and initial treatment received at our center. ResultsPresenting WIfI stages were 1 to 2 (23%), 3 (27%), and 4 (50%). Index revascularization approach was endoluminal (59%), autogenous vein bypass (29%), or non-autogenous bypass (13%). Operative mortality within 30 days was 2.9% and was not associated with WIfI stage or revascularization approach. Median limb follow-up time was 502 days (interquartile range [IQR], 112-1256 days), and median survival follow-up time was 932 days (IQR, 343-1770 days). Major amputation or death occurred in 19% and 46% of patients at median times of 119 days (IQR, 28-314 days) and 739 days (IQR, 204-1475 days), respectively. WIfI stage was independently associated with major amputation (P = .001), as was initial revascularization approach (P = .01). In a Cox proportional hazards model, factors independently associated with major amputation were male sex (hazard ratio [HR], 1.4; 95% confidence interval [CI], 1.04-2.0; P = .03), diabetes (HR, 1.8; 95% CI, 1.3-2.5; P = .001), WIfI stage 4 (HR, 2.3; 95% CI, 1.5-3.5; P < .001), and non-autogenous bypass (HR, 2.9; 95% CI, 2.1-4.2; P < .001). In a Cox proportional hazards model for mortality, independently associated factors were age (HR, 1.04; 95% CI, 1.02-1.05; P < .001), end-stage renal disease (HR, 2.8; 95% CI, 1.9-4.0; P < .001), congestive heart failure (HR, 1.9; 95% CI, 1.4-2.5; P < .001), chronic obstructive pulmonary disease (HR, 1.5; 95% CI, 1.1-2.1; P = .02), and WIfI stage 4 (HR, 1.6; 95% CI, 1.04-2.2; P = .03). Among those presenting with WIfI stage 4 limbs, Kaplan-Meier estimated rates of freedom from major amputation or death at 2 years were 71% ± 3.7% and 68% ± 3.5%, respectively. In an inverse propensity weighted Cox proportional hazards model, non-white race (HR, 1.5; 95% CI, 1.01-2.2; P = .047), diabetes (HR, 2.0; 95% CI, 1.2-3.3; P = .008), Global Anatomic Staging System infrapopliteal grade (HR, 1.2; 95% CI, 1.05-1.3; P = .005), non-autogenous bypass (HR, 3.2; 95% CI, 1.9-5.3; P < .001), and endoluminal revascularization (HR, 2.6; 95% CI, 1.6-4.3; P < .001) were independently associated with major amputation in the WIfI stage 4 subgroup. ConclusionsPresenting WIfI stage is strongly associated with long-term risks of major amputation and death following infrainguinal revascularization for CLTI and should be used to stratify outcomes comparisons. Effective revascularization is critical in WIfI stage 4 disease, and autogenous vein bypass provides durable long-term limb preservation.

Open revascularization approach is associated with healing and ambulation after transmetatarsal amputation in patients with chronic limb threatening ischemia

BackgroundTransmetatarsal amputation (TMA) allows for maintenance of ambulatory function for patients with significant forefoot tissue loss. Effective revascularization is key to optimizing limb salvage for patients with chronic limb threatening ischemia (CLTI). We hypothesized that CLTI patients requiring TMA will have better healing and functional outcomes with open bypass than with endovascular revascularization. MethodsConsecutive TMAs performed at three affiliated centers between 2008 and 2020 were retrospectively reviewed. The baseline characteristics, including WIfI (wound, ischemia, foot infection) stage, noninvasive vascular studies, healing, and ambulatory outcomes, were collected. Catheter-based angiographic images were evaluated using the GLASS (global limb anatomic staging system). The primary outcomes were TMA healing and community ambulation. The secondary outcomes were TMA that had healed at study end, any ambulatory function postoperatively, major amputation, and mortality. Descriptive statistics and univariate, multivariable, and Kaplan-Meier analyses were performed. ResultsA total of 346 TMAs had been performed in 318 patients, 209 of whom had had peripheral artery disease (PAD). The median follow-up was 2.5 years. Patients with PAD had had significantly lower rates of healing compared with those without PAD (64% vs 77%; P = .007). Revascularization was performed in 185 limbs, with 102 treated endovascularly and 83 with open surgery. The patients who had undergone endovascular surgery were significantly less likely to have had the TMA healed at any point (55% vs 76%; P = .003) and less likely to have remained healed at study end (49% vs 66%; P = .02). Patients with GLASS stage 3 anatomy were significantly more likely to have healed after open surgery (75% vs 45%; P = .003). Long-term ambulation data were available for 72% of the revascularized patients. Endovascular surgery was associated with a lower likelihood of community ambulation after TMA (34% vs 57%; P = .002). On multivariable analysis, open surgery was significantly associated with TMA healing (odds ratio, 2.8; P = .007) and ambulation (odds ratio, 2.9; P = .001). ConclusionsFor patients with CLTI and significant tissue loss requiring TMA, an initial open approach to revascularization was associated with improved healing and higher rates of ambulation compared with endovascular interventions. The metabolic requirement for healing of a TMA in patients with CLTI might be better met by open revascularization.

Pedal arterial calcification score is associated with hemodynamic change and major amputation after infrainguinal revascularization for chronic limb-threatening ischemia.

Pedal medial arterial calcification (pMAC) is associated with major amputation in patients with chronic limb-threatening ischemia (CLTI). We hypothesize that this association would be related to unresolved distal ischemia. We investigated relationships across pMAC score, hemodynamic change, and major amputation after infrainguinal revascularization for CLTI. This is a single-institution, retrospective study of 306 patients who underwent technically successful infrainguinal revascularization for CLTI (2011-2020) and had foot x-rays for blinded pMAC scoring (0-5). A total of 136 (44%) patients had toe pressure measurements performed within 90days before and 60days after revascularization. Ischemia grade (0-3) was assigned using the Society for Vascular Surgery Wound, Ischemia, foot Infection (WIfI) system. The revascularization approach was open bypass in 118 (38%) and endovascular in 188 (62%) patients. pMAC scores were trichotomized (0-1 [125; 41%], 2-4 [116; 38%], 5 [65; 21%]). Post-revascularization WIfI ischemia grade was improved in 78 of 136 (57%) and unchanged/worsened in 58 of 136 (43%). A lower pMAC score was associated with hemodynamicimprovement (P= .004). Failure to improve the ischemia grade was associated with major amputation (P= .0002). In the endovascular subgroup, WIfI ischemia grade was improved in 43 of 90 (48%) with available measurements, and 37 of 188 (20%) underwent major amputation. In a multivariate logistic model, pMAC 5 was the only factor independently associated with unimproved ischemia grade after endovascular treatment (odds ratio: 4.0 [1.1-16.6], P= .04). In a Cox proportional hazards model, factors independently associated with major amputation after endoluminal revascularization were WIfI stage 4 (hazard ratio [HR]: 2.7 [1.3-5.7], P= .007) and pMAC score (pMAC: 2-4: HR: 10.6 [1.4-80.7], P= .02; pMAC: 5: HR: 15.5 [2.0-119], P= .008). In the bypass subgroup, WIfI ischemia grade was improved in 35 of 46 (76%) with available measurements but was not associated with pMAC score (P= .88) or any other baseline patient or limb characteristics. A total of 19 of 118 (16%) patients underwent major amputation. In a Cox proportional hazards model including bypass conduit, WIfI stage, and pMAC score, the only factor independently associated with major amputation after bypass was use of nonautologous conduit (HR: 5.6 [1.8-17.6], P= .003). The pMAC score is independently associated with persistent distal ischemia and major amputation after technically successful revascularization for CLTI. These data suggest that pMAC may be a marker for hemodynamic response to revascularization and risk of limb loss, and it may have a stronger influence on the outcome of endoluminal interventions.

Arterial spin labeling magnetic resonance imaging quantifies tissue perfusion around foot ulcers.

Tools that quantify tissue perfusion of the foot are deficient, contributing to the uncertainty in predicting ulcer healing potential. This pilot study aims to quantify peri-wound foot perfusion at various tissue depths using a novel application of pseudo-continuous arterial spin labeling magnetic resonance imaging. Ten diabetic patients with neuropathic wounds and 20 healthy volunteers without wounds were recruited. Wounds were graded according to the Wound, Ischemia, Foot Infection (WIfI) system. All subjects underwent a noncontrasted ASL MRI of the foot for perfusion measurements. For healthy volunteers, perfusion was compared at rest and during sustained toe flexion between four regions: lateral plantar, medial plantar, lateral calcaneal, and medial calcaneal. Evaluations of diabetic volunteers compared perfusion between four zones: wound, near border, far border, and remote. Remote zone perfusion in diabetics was compared with perfusion in the plantar foot of healthy volunteers. There were 11 wounds, which were located over the metatarsal heads in five, the stump of a transmetatarsal amputation in three, the heel in two, and the mid foot in one. The median WIfI stage was 2. One patient had a WIfI ischemia grade of 1; the remaining patients' grades were 0. The mean ankle-brachial index was 1.0± 0.3. There were two patients with a WIfI foot infection grade of 1; the remaining patients' grades were 0. In healthy volunteers, plantar foot perfusion with sustained toe flexion was 43.9± 1.7mL/100g/min and significantly higher than perfusion at rest (27.3± 2.7mL/100g/min; P< .001). In diabetic patients, perfusion at the wound, near border, far border, and remote regions was 96.1± 10.7, 92.7± 9.4, 73.4± 8.2, and 62.8± 2.7mL/100g/min. Although this perfusion pattern persisted throughout the depth of the wound, perfusion decreased with tissue depth. In the near border, perfusion at 20% of the wound depth was 124.0± 35.6mL/100g/min and 69.9± 10.1mL/100g/min at 100% (P= .006). Lastly, remote perfusion in diabetics was 2.3 times the plantar perfusion in healthy volunteers (27.3± 2.7mL/100g/min; P< .001). The pattern of resting tissue perfusion around nonischemic diabetic foot ulcers was successfully quantified with arterial spin labeling magnetic resonance imaging. Diabetic patients with wounds were hyperemic compared withhealthy volunteers. There was a 1.5-fold increase in peri-wound tissue perfusion relative to the rest of the foot. This study is the first step in developing a tool to assess the perfusion deficit in ischemic wounds.

Analysis of wound healing time and wound-free period in patients with chronic limb-threatening ischemia treated with and without revascularization.

The traditionally reported outcomes for patients with ischemic wounds have centered on amputation-free survival. However, that discounts the importance of other patient-centered outcomes such as the wound healing time (WHT) and wound-free period (WFP). We evaluated the long-term wound outcomes of patients treated for chronic limb-threatening ischemia at our institution. From 2014 to 2017, we identified all patients with chronic limb-threatening ischemia and ischemic wounds using symptomatic and hemodynamic criteria. The primary data included the wound size, wound location, WIfI (wound, ischemia, foot infection) grade, WHT, WFP, minor and major amputation, and death. Wounds were not considered healed if the patient had required a major amputation or had died before wound healing. The WHT was calculated as the interval in days between the diagnosis and determination of a healed wound. The WFP was calculated as the interval in days between a healed wound and wound recurrence, major amputation, death, or the end of the study period. A comparison of the wound healing parameters stratified by revascularization status was performed using the Student t test. A generalized linear model adjusted for age, sex, initial wound size, and WIfI grade was used to evaluate the risk of wound healing with and without revascularization. A total of 256 patients had presented with 372 wounds. Of the 256 patients, 48% had undergone revascularization. During the study period, 97 minor amputations and 100 major amputations had been required, and 132 patients had died. The average wound size was 13.9± 52.0cm2; however, for the 155 wounds that had healed, the average size was only 4.0± 9.6cm2(P= .002). No differences were found in the wound size when stratified by revascularization status (P= .727). Adjusted for the initial wound size, the risk of wound healing was not different when stratified by revascularization (risk ratio, 1.22; 95% confidence interval, 0.80-1.87; P= .354). For those whose wounds had healed, the average WHT and WFP were 173± 169days and 775± 317days, respectively. The WHT was not faster for the revascularized group (155days vs 188days; P= .221). When stratified by revascularization status, the rate of wound recurrence was 4.6 vs 8.9 wounds per 100 person-years for the revascularized and nonrevascularized groups, respectively (P= .125). In our study, we found that, except for patients who presented with severe ischemia, revascularization was not associated with improved rates of wound healing. Among the wounds that healed, regardless of the initial ischemia grade, revascularization was not associated with a faster WHT or longer WFPs.

Relationship between WIfI stage and quality of life at revascularization in the BEST-CLI trial

ObjectiveThe WIfI (Wound, Ischemia, foot Infection) stage measures the extent of wounds, ischemia, and foot infection in patients with chronic limb threatening ischemia (CLTI) and has been associated with the risk of major amputation. Patients with CLTI have impaired health-related quality of life (HRQoL), which can be multifactorial. We hypothesized that the severity of the limb threat (WIfI stage) would be associated with poor HRQoL among patients with CLTI presenting for revascularization. MethodsThe dataset of the BEST-CLI (best endovascular versus best surgical therapy in patients with CLTI) trial, a prospective, randomized trial comparing open and endovascular revascularization strategies, was queried for HRQoL assessments at patient enrollment. The HRQoL assessments included (1) Vascular Quality of Life; (2) 12-item short form survey (SF-12), containing the utility index score (short-form six-dimension R2 utility index, incorporating physical, emotional, and mental well-being) and mental and physical components; and (3) the EQ-5D. Multivariable regression analysis was used to identify the independent associations with the baseline HRQoL assessments. ResultsA total of 1568 patients with complete WIfI data were analyzed, of whom 71.5% were men. The WIfI distribution was 35.5% with stage 4, 29.6% with stage 3, 28.6% with stage 2, and 6.3% with stage 1. Patients presenting with WIfI stage 4, compared with stage 1 to 3, were more often men (74.9% vs 69.6%) and current smokers (25.4% vs. 17.6%), had had end-stage renal disease (13.3% vs 8.5%) and diabetes (83.6% vs 60.2%), were not independently ambulatory (56.8% vs 38.5%), and had had higher median morbidity scores (4 vs 3; P < .05 for all). On multivariable analysis, WIfI stage 4, compared with stage 1 to 3, was associated with lower SF-12 mental component scale scores (estimate, −2.43; 95% confidence interval, −3.73 to −1.13; P < .001) and short-form six-dimension R2 utility index scores (estimate, −0.02; 95% confidence interval, −0.03 to 0.001; P = .04). The WIfI stage was not independently associated with the baseline Vascular Quality of Life, SF-12 physical component scale, or EQ-5D assessments. ConclusionsWIfI stage was independently associated with poorer quality of life because of mental, rather than physical, health for patients with CLTI. Clinicians should be aware of the burden of mental stress borne by those with the greatest limb impairment.

Racial and ethnic disparities in major adverse limb events persist for chronic limb threatening ischemia despite presenting limb threat severity after peripheral vascular intervention

ObjectiveRacial and ethnic disparities have been well-documented in the outcomes for chronic limb threatening ischemia (CLTI). One purported explanation has been the disease severity at presentation. We hypothesized that the disparities in major adverse limb events (MALE) after peripheral vascular intervention (PVI) for CLTI would persist despite controlling for disease severity at presentation using the WIfI (Wound, Ischemia, foot Infection) stage. MethodsThe Vascular Quality Initiative PVI dataset (2016-2021) was queried for CLTI. Patients were excluded if they were missing the WIfI stage. The primary end point was the incidence of 1-year MALE, defined as major amputation (through the tibia or fibula or more proximally) or reintervention (endovascular or surgical) of the initial treatment limb. A multivariate hierarchical Fine-Gray analysis was performed, controlling for hospital variation, competing risk of death, and presenting WIfI stage, to assess the independent association of Black/African American race and Latinx/Hispanic ethnicity with MALE. A Cox proportional hazard regression model was used for the 1-year survival analysis. ResultsOverall, 47,830 patients (60%) had had WIfI scores reported (73% White, 20% Black, and 7% Latinx). The 1-year unadjusted cumulative incidence of MALE was 13.1% (95% confidence interval [CI], 12.6%-13.5%) for White, 14.3% (95% CI, 13.5%-15.3%) for Black, and 17.0% (95% CI, 15.3%-18.9%) for Latinx patients. On bivariate analysis, the occurrence of MALE was significantly associated with younger age, Black race, Latinx ethnicity, coronary artery disease, cerebrovascular disease, congestive heart failure, hypertension, diabetes, dialysis, intervention level, any prior minor or major amputation, and WIfI stage (P < .001). The cumulative incidence of 1-year MALE increased by increasing WIfI stage: stage 1, 11.7% (95% CI, 10.9%-12.4%); stage 2, 12.4% (95% CI, 11.8%-13.0%); stage 3, 14.8% (95% CI, 13.8%-15.8%); and stage 4, 15.4% (95% CI, 14.3%-16.6%). The cumulative incidence also increased by intervention level: inflow, 10.7% (95% CI, 9.8%-11.7%), femoropopliteal, 12.3% (95% CI, 11.7%-12.9%); and infrapopliteal, 14.1% (95% CI, 13.5%-14.8%). After adjustment for WIfI stage only, Black race (subdistribution hazard ratio [SHR], 1.30; 95% CI, 1.17-1.44; P < .001) and Latinx ethnicity (SHR, 1.58; 95% CI, 1.37-1.81; P < .001) were associated with an increased 1-year hazard of MALE compared with White race. On adjusted multivariable analysis, MALE disparities persisted for Black/African American race (SHR, 1.12; 95% CI, 1.01-1.25; P = .028) and Latinx/Hispanic ethnicity (SHR, 1.34; 95% CI, 1.16-1.54; P < .001) compared with White race. ConclusionsBlack/African American and Latinx/Hispanic patients had a higher associated hazard of MALE after PVI for CLTI compared with White patients despite an adjustment for WIfI stage at presentation. These results suggest that disease severity at presentation does not account for disparities in outcomes. Further work should focus on better understanding the underlying mechanisms for disparities in historically marginalized racial and ethnic groups presenting with CLTI.

Severe inframalleolar disease is an independent predictor of adverse limb outcomes after endovascular revascularization in chronic limb-threatening ischemia

ObjectiveIn the present study, we evaluated the effects of inframalleolar (IM) disease on the occurrence of major adverse limb events (MALE) in patients undergoing endovascular revascularization for chronic limb-threatening ischemia (CLTI). MethodsPatients who had undergone endovascular revascularization for CLTI between January 2015 and December 2019 at two university-affiliated hospitals were reviewed retrospectively. Patients with severe IM disease (pedal score of 2) were compared with those with mild to moderate IM disease (score of 0 or 1) using the Global Vascular Guidelines. The primary outcome was MALE (open revascularization, acute leg ischemia, major amputation). The secondary outcomes were mortality, reintervention, major adverse cardiac events, and perioperative complications ≤30 days after endovascular revascularization, primary limb-based patency, and the occurrence of any limb event (defined as any amputation, acute leg ischemia, or open revascularization). Kaplan-Meier estimates were used to compare the primary outcome, and the Cox proportion hazard model was used to assess the effects of IM disease. ResultsThe study included 167 limbs in 149 patients (36% female; mean age, 74 ± 12 years). Severe IM disease was identified in 71 limbs (43%). No differences were found in the baseline characteristics, except for a higher prevalence of dyslipidemia in the patients with severe IM disease (66% vs 43%; P = .003). Most patients in both groups had had a WIfI (Wound, Ischemia, foot Infection) score of 4 (severe IM disease, 64%; vs mild to moderate IM disease, 57%; P = .462) and GLASS (global limb anatomic severity scale) III anatomy (severe IM disease, 54%; vs mild to moderate IM disease, 48%; P = .752). The Kaplan-Meier estimates showed that severe IM disease was associated with lower freedom from MALE (69% vs 82%; P = .026). The Cox proportion hazard regression model showed that severe IM disease was an independent predictor of increased MALE and amputation risk (hazard ratio, 1.715; 95% confidence interval, 1.015-2.896; P = .044) after adjusting for covariates. During follow-up, patients with severe IM disease had had mortality (27% vs 31%; P = .567) and reintervention (42% vs 38%; P = .608) similar to those for patients with mild to moderate IM disease. Primary limb-based patency was also similar (79% vs 84%; P = .593) at a mean follow-up of 3.8 ± 0.8 years. ConclusionsSevere IM disease was prevalent in 43% of limbs that had undergone endovascular revascularization for CLTI and was associated with lower freedom from MALE. Severe IM disease also independently increased the hazard of adverse limb outcomes and amputations in patients with CLTI by >70%, highlighting its importance as a measure of foot perfusion.

Relationship Between WIfI (Wound, Ischemia, Foot Infection) Stage and Quality of Life at Revascularization in Best-CLI (Best Endovascular vs. Best Surgical Therapy in Patients With Critical Limb Ischemia) Trial

The WIfI (wound, ischemia, foot infection) stage measures the extent of wounds, ischemia, and foot infection in patients with chronic limb-threatening ischemia (CLTI) and has been associated with a risk of major amputation. Patients with CLTI will have an impaired quality of life (QOL), which can be multifactorial in nature. We hypothesized that the severity of the limb threat (WIfI) would be associated with QOL for patients with CLTI undergoing revascularization.

The Society for Vascular Surgery WIfI (Wound, Ischemia, Foot Infection) Classification Does not Predict for Successful Healing Following Transmetatarsal Amputation

The Society for Vascular Surgery WIfI (wound, ischemia, foot infection) classification has been shown to accurately predict for limb salvage for patients with chronic limb-threatening ischemia (CLTI). However, its ability to predict for limb salvage after transmetatarsal amputation (TMA) is unknown.

Ankle Brachial Index and Wound Classification Teaching to Providers as Part of a Comprehensive Limb Preservation Outreach Program

The use of evidence-based specialty guidelines is low in primary care settings. However, the early use of ankle brachial index (ABI) testing and a validated wound classification system allows for the prompt referral of patients for specialty care. We implemented a program to teach providers ABI testing and the use of the WIfI (wound, ischemia, foot infection) classification tool. In the present report, we have described the program outcomes.

Limb-based patency as a measure of effective revascularization for chronic limb-threatening ischemia

ObjectiveIn 2019, the Global Vascular Guidelines on chronic limb-threatening ischemia (CLTI) introduced the concept of limb-based patency (LBP) defined as maintained patency of a target artery pathway after intervention. The purpose of this study was to investigate the relationship between LBP and major adverse limb events (MALE) after infrainguinal revascularization for CLTI. MethodsConsecutive patients undergoing revascularization for CLTI between 2016 and 2019 at a single tertiary institution with a dedicated limb preservation team were included. Subjects with aortoiliac disease, prior infrainguinal stents, or existing bypass grafts were excluded. Demographics, Global Limb Anatomic Staging System scores, Wound, Ischemia, foot Infection (WIfI) stages, revascularization details, and limb-specific outcomes were reviewed. LBP was defined by the absence of reintervention, occlusion, critical stenosis (>70%), or hemodynamic compromise with ongoing symptoms of CLTI. MALE included thrombectomy or thrombolysis, new bypass, open surgical graft revision and/or major amputation. ResultsWe analyzed 184 unique limbs in 163 patients. This cohort was composed of 66.9% male patients with a mean age of 72 years. Baseline characteristics included diabetes (66%), tissue loss (91%), and advanced WIfI stages (30% stage 3, 51% stage 4). Global Limb Anatomic Staging System stage 3 anatomic patterns were common (n = 119 [65%]). Sixty limbs were treated with open bypass (65% involving tibial targets) and 124 underwent endovascular intervention (70% including infrapopliteal targets). The 12-month freedom from MALE and loss of LBP were 74.0% ± 3.7% and 48.6% ± 4.2%, respectively. Diabetes (hazard ratio [HR], 2.56; 95% confidence interval [CI], 1.13-5.83; P = .025) and loss of LBP (HR, 4.12; 95% CI, 1.96-8.64; P < .001) were independent predictors of MALE in a Cox proportional hazard model. Loss of LBP was the sole independent predictor of major limb amputation after revascularization (HR, 4.97; 95% CI, 1.89-13.09; P = .001). Loss of LBP impacted both intermediate-risk limbs (HR, 2.85; 95% CI, 1.02-7.97; P = .047 in WIfI stages 1-3) and high-risk limbs (HR, 3.99; 95% CI, 1.32-12.11; P = .014 in WIfI stage 4). However, the loss of LBP had the greatest impact on patients presenting with WIfI stage 4 disease (31% vs 8% major limb amputation at 12 months in limbs without vs with maintained LBP). ConclusionsThe anatomic durability of revascularization, as measured by LBP, is a key determinant of treatment outcomes in CLTI regardless of the initial mode of intervention undertaken. Loss of LBP is most detrimental in patients presenting with advanced limb threat (WIfI stage 4).

WIfI Staging and Long-term Outcomes After Infrainguinal Revascularization for Chronic Limb-threatening Ischemia

The Society for Vascular Surgery wound, ischemia, foot infection (WIfI) limb staging system was established to estimate risk of major amputation in chronic limb-threatening ischemia (CLTI) and to better stratify outcomes comparisons. There is little data on treatment outcomes beyond 1 year based on presenting WIfI stage.

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

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). 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>2cm in the dorsalis pedis, plantar, and metatarsal arteries and >1cm in the hallux and non-hallux digital arteries. 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 759days (interquartile range, 264-1541days). 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. 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.