Validation of the Global Limb Anatomic Staging System in first-time lower extremity revascularization.

The Global Limb Anatomic Staging System (GLASS) was developed as a new anatomic classification scheme to grade the severity of chronic limb threatening ischemia. We evaluated the ability of this anatomic grading system to determine major adverse limb events after lower extremity revascularization. We performed a single-institutional retrospective review of 1060 consecutive patients who had undergone 1180 first-time open or endovascular revascularization procedures for chronic limb threatening ischemia from 2005 to 2014. Using the review of angiographic images, the limbs were classified as GLASS stage 1, 2, or 3. The primary composite outcome was reintervention, major amputation (below- or above-the-knee amputation), and/or restenosis (>3.5× step-up by duplex criteria) events (RAS). The secondary outcomes included all-cause mortality, failure to cross the lesion by endovascular methods, and a comparison between bypass vs endovascular intervention. Kaplan-Meier estimates were used to determine the event rates at 1 and 5 years, and Cox regression analysis was used to adjust for baseline differences among the GLASS stages. Of all patients undergoing first-time revascularization, imaging studies were available for 1180 procedures (91%) for GLASS grading. Of these procedures, 552 were open bypass (47%) and 628 were endovascular intervention (53%). Compared with GLASS stage 1 disease (n = 267, 23%), stage 2 (n = 367; 31%) and stage 3 (n = 546; 42%) disease were associated with a greater risk of RAS at 1 year (stage 1, 33% vs stage 2, 48% vs stage 3, 53%) and 5 years (stage 1, 45% [reference]; stage 2, 65%; hazard ratio [HR], 1.7; 95% confidence interval [CI], 1.3-2.2; P < .001; stage 3, 69%; HR, 2.3; 95% CI, 1.7-2.9; P < .001). These differences were mainly driven by reintervention and restenosis rather than by major amputation. The 5-year mortality was similar for stage 2 and 3 compared with stage 1 disease (stage 1, 40% [reference]; stage 2, 45%; HR, 1.1; 95% CI, 0.8-1.4; P = .69; stage 3, 49%; HR, 1.2; 95% CI, 1.0-1.6; P = .11). For all attempted endovascular interventions, failure to cross a target lesion increased with advancing GLASS stage (stage 1, 4.5% vs stage 2, 6.3% vs stage 3, 13.3%; P < .01). Compared with open bypass (n = 552; 46.8%), endovascular intervention (n = 628; 53.3%) was associated with a higher rate of 5-year RAS for GLASS stage 1 (49% vs 34%; HR, 1.9; 95% CI, [1.1-3.5; P = .03), stage 2 (69% vs 52%; HR, 1.7; 95% CI, 1.2-2.5; P < .01), and stage 3 (83% vs 61%; HR, 1.5; 95% CI, 1.2-2.0; P < .01) disease. For patients undergoing first-time lower extremity revascularization, the GLASS can be used to predict for reintervention and restenosis. Bypass resulted in better long-term outcomes compared with endovascular intervention for all GLASS stages.

Liang P ，Marcaccio CL ，Darling JD ，Kong D ，Rao V ，St John E ，Wyers MC ，Hamdan AD ，Schermerhorn ML ... -  《-》

Predictive ability of the Society for Vascular Surgery Wound, Ischemia, and foot Infection (WIfI) classification system after first-time lower extremity revascularizations.

The Society for Vascular Surgery (SVS) Wound, Ischemia and foot Infection (WIfI) classification system was proposed to predict 1-year amputation risk and potential benefit from revascularization. Our goal was to evaluate the predictive ability of this scale in a real-world selection of patients undergoing a first-time lower extremity revascularization for chronic limb-threatening ischemia (CLTI). From 2005 to 2014, 1336 limbs underwent a first-time lower extremity revascularization for CLTI, of which 992 had sufficient data to classify all three WIfI components (wound, ischemia, and foot infection). Limbs were stratified into the SVS WIfI clinical stages (from 1 to 4) for 1-year amputation risk estimation, a novel WIfI composite score from 0 to 9 (that weighs all WIfI variables equally), and a novel WIfI mean score from 0 to 3 (that can incorporate limbs missing any of the three WIfI components). Outcomes included major amputation; revascularization, major amputation, or stenosis (>3.5× step-up by duplex; RAS) events; and death. Predictors were identified using Cox regression models and Kaplan-Meier survival estimates. Of the 1336 first-time procedures performed, 992 limbs were classified in all three WIfI components (524 endovascular and 468 bypass; 26% rest pain and 74% tissue loss). Cox regression demonstrated that a one-unit increase in the WIfI clinical stage increases the risk of major amputation (hazard ratio [HR], 2.4; 95% confidence interval [CI], 1.7-3.2) and RAS events in all limbs (HR, 1.2; 95% CI, 1.1-1.3). Separate models of the entire cohort, a bypass-only cohort, and an endovascular-only cohort showed that a one-unit increase in the WIfI mean score is associated with an increase in the risk of major amputation (all three cohorts: HR, 5.3 [95% CI, 3.6-6.8], 4.1 [2.4-6.9], and 6.6 [3.8-11.6], respectively) and RAS events (all three cohorts: HR, 1.7 [95% CI, 1.4-2.0], 1.9 [1.4-2.6], and 1.4 [1.1-1.9], respectively). The novel WIfI composite and WIfI mean scores were the only consistent predictors of death among the three cohorts, with the WIfI mean score proving most strongly predictive in the entire cohort (HR, 1.4; 95% CI, 1.1-1.7), the bypass-only cohort (HR, 1.5; 95% CI, 1.1-1.9), and the endovascular-only cohort (HR, 1.4; 95% CI, 1.0-1.8). Although the individual WIfI wound component was able to predict mortality among all patients (HR, 1.1; 95% CI, 1.0-1.2) and bypass-only patients (HR, 1.2; 95% CI, 1.1-1.3), neither the additional individual WIfI components nor the WIfI clinical stage were able to significantly predict mortality among any cohort. This study supports the ability of the SVS WIfI classification system to predict major amputation; however, the novel WIfI mean and WIfI composite scores predict amputation, RAS events, and mortality more consistently than any other current WIfI scoring system. The WIfI mean score allows inclusion of all limbs, and both novel scoring systems are easier to conceptualize, give equal weight to each WIfI component, and may provide clinicians more effective comparisons in outcomes between patients.

Darling JD ，McCallum JC ，Soden PA ，Guzman RJ ，Wyers MC ，Hamdan AD ，Verhagen HJ ，Schermerhorn ML ... -  《-》

Predictors of major adverse lower limb events in patients with tissue loss secondary to critical limb-threatening ischemia.

Chronic limb-threatening ischemia (CLTI) is the end-stage of peripheral arterial disease (PAD) posing a high risk for limb loss and mortality. This study aims to evaluate and list possible predictors of major adverse limb events (MALEs) in CLTI patients with tissue loss. This retrospective study included all Rutherford-Becker stage 5 or 6 patients who required foot debridement and revascularization in our department from January 2016 to December 2018. The limbs were classified according to the TASC II, GLASS and WiFI grading systems. The primary composite outcome was MALEs at 2 years. The secondary outcomes included all-cause mortality, primary patency, freedom from reintervention, and major amputation. Kaplan-Meier estimates were used to determine the event rates, and Cox proportional hazards model with the index MALE as a time-dependent covariate was used to search for MALEs predictors. Of 241 included patients, 19 underwent open surgeries (7.9 %) 207 had endovascular interventions (85.9 %) and 15 required a hybrid approach (6.2 %). On univariate analysis, patients who experienced MALEs (n = 111) more often required hemodialysis (25 vs 15; p = .02), presented with more complex lesions (TASC D on femoropopliteal (p = .05) or below the knee (BTK) arteries (p = .006) with increasing infra-inguinal GLASS Stage (p < .0001)), a history of index limb open (p = .009) or endovascular (p = .049) revascularization, an occluded tibial artery (p = .002 for the posterior tibial and p = .052 for the anterior tibial), or a "desert foot" (p = .02). The CRP level was also higher at admission (p = .001). Technical success of BTK revascularization significantly reduced MALEs (p < .0001) along with the number of patent BTK vessels (p = .0007). Independent predictors of MALEs included hemodialysis (HR = 2.00; 95%CI: 1.14 to 3.39), pulsatile arterial pressure (HR = 1.01; 95%CI: 1.00 to 1.03) and the infra-inguinal GLASS Stage (HR = 2.50; 95%CI: 1.17 to 5.82). We could not correlate our results with the WiFI scores for amputation risk and revascularization benefit. For patients with CLTI at the stage of trophic disorders, with or without a history of index limb revascularization, the GLASS successfully predicted MALEs. Hemodialysis and high pulsatile arterial pressure increased the risk of MALEs. The WiFI score did not demonstrate its interest in this subgroup of patients.

Vosgin-Dinclaux V ，Bertucat P ，Dari L ，Webster C ，Foussard N ，Mohammedi K ，Ducasse E ，Caradu C ... -  《-》

The Global Limb Anatomic Staging System is associated with outcomes of infrainguinal revascularization in chronic limb threatening ischemia.

The Global Limb Anatomic Staging System (GLASS) has been proposed to facilitate clinical decision-making regarding revascularization for chronic limb threatening ischemia (CLTI). The purpose of the present study was to define its relationship to the treatment outcomes in CLTI. Consecutive patients who had undergone peripheral angiography for rest pain or tissue loss from January 2017 to July 2019 at a tertiary referral center with a dedicated limb preservation program were reviewed. Subjects with significant aortoiliac disease, previous infrainguinal stenting or functioning bypass grafts, or GLASS stage 0 were excluded. The GLASS score was assigned from the preintervention angiography findings, and the treating surgeon determined the primary infrapopliteal target artery pathway for the limb at risk. The demographic data, procedural details, and clinical outcomes were analyzed. The study cohort included 167 patients and 194 limbs, of which 175 of 194 limbs (90%) had presented with tissue loss and 149 of 182 limbs (83%) with WIfI (Wound, Ischemia and foot Infection) stage 3 or 4. The GLASS stage was GLASS 1 in 14%, GLASS 2 in 18%, and GLASS 3 in 68%. GLASS 3 anatomy was present in 85% of 52 limbs treated by bypass and 55% of 108 limbs treated by endovascular intervention (EVI; P < .001). Revascularization was not performed in 34 limbs, most of which were GLASS 3 (85%). Immediate technical failure for EVI (ie, failure to establish target artery pathway) occurred exclusively in the setting of GLASS 3 anatomy (n = 13; 22%). After a median follow-up of 10 months, limb-based patency after EVI was significantly lower in GLASS 3 than in GLASS 1 or 2 limbs (42% vs 59%; P = .018). GLASS 3 was associated with reduced major adverse limb events-free survival in both the EVI group (P = .002) and the overall revascularized cohort (P = .001). GLASS 3 was also associated with significantly reduced overall survival, amputation-free survival, and reintervention-free survival. In a Cox proportional hazards model, GLASS 3 (hazard ratio, 2.35; 95% confidence interval, 1.30-4.24; P = .005) and WIfI wound grade 3 (hazard ratio, 2.64; 95% confidence interval, 1.26-5.53; P = .010) were independent predictors of reduced major adverse limb events-free survival after revascularization. GLASS stage 3 was strongly associated with major adverse clinical outcomes after revascularization in patients with CLTI.

El Khoury R ，Wu B ，Edwards CT ，Lancaster EM ，Hiramoto JS ，Vartanian SM ，Schneider PA ，Conte MS ... -  《-》

Society for Vascular Surgery limb stage and patient risk correlate with outcomes in an amputation prevention program.

Clinical decision making and accurate outcomes comparisons in advanced limb ischemia require improved staging systems. The Society for Vascular Surgery Lower Extremity Threatened Limb Classification System (Wound extent, Ischemia, and foot Infection [WIfI]) was designed to stratify limb outcomes based on three major factors-wound extent, ischemia, and foot infection. The Project or Ex-Vivo vein graft Engineering via Transfection III (PREVENT) III (PIII) risk score was developed to stratify patients by expected amputation-free survival (AFS) after surgical revascularization. This study was designed to prospectively assess limb and patient-based staging for predicting outcomes of hospitalized patients in an amputation prevention program. This study undertook a retrospective analysis of prospectively gathered registry data of consecutive patients with limb-threatening conditions admitted to a fully integrated vascular/podiatry service over a 16-month period. Upon admission, limb risk was stratified using the WIfI system and patient risk was categorized using PIII classification. Patients were assessed for perioperative and postdischarge outcomes, and their relationship to staging at admission was analyzed. There were 174 threatened limbs (143 hospitalized patients) stratified by WIfI stage (1%-12%, 2%-28%, 3%-24%, 4%-28%, 5%-3%, unstaged-5%) and PIII risk (34% low, 49% moderate, and 17% high risk). Diabetes and end-stage renal disease were associated with WIfI stage (P = .006 and P = .018) and PIII risk (P = .003 and P < .001). Perioperative (30-day) events included 3% mortality, 8% major adverse cardiovascular events and 2.4% major amputation. There were 119 limbs (71%) that underwent revascularization, including 108 infrainguinal reconstructions (endovascular or open revascularization). Rate of revascularization increased with WIfI stage (P < .001), concomitant with the number of podiatric procedures, minor amputations, and initial hospital duration of stay (all P < .001). Increased WIfI stage was associated with major adverse limb events (P = .018), reduced limb salvage (P = .037), and decreased AFS (P = .048). In contrast, PIII risk category was associated with mortality (P < .001) and AFS (P < .001). Among infrainguinal reconstruction procedures, there was a similar distribution of endovascular (46%) and surgical (54%) interventions. Freedom from major adverse limb events was best for autogenous vein bypass (P = .025), and surgical revascularization was associated with improved limb salvage among the most severely threatened limbs (WIfI stage 4: 95% limb salvage for open bypass vs 68% limb salvage for endovascular; P = .026). Among patients hospitalized with limb-threatening conditions and treated by a multidisciplinary amputation prevention team, PIII risk correlates with mortality whereas WIfI stage strongly predicts initial hospital duration of stay, and key mid-term limb outcomes. Surgical revascularization performed best in the limbs at greatest risk (WIfI stage 4), and autogenous vein bypass was the preferred conduit for open bypass. These data support the use of WIfI and PIII as complementary staging tools in the management of chronic limb-threatening ischemia.

Causey MW ，Ahmed A ，Wu B ，Gasper WJ ，Reyzelman A ，Vartanian SM ，Hiramoto JS ，Conte MS ... -  《-》