How multidisciplinary clinics may mitigate socioeconomic barriers to care for chronic limb-threatening ischemia.

OBJECTIVE: Although multidisciplinary clinics improve outcomes in chronic limb-threatening ischemia (CLTI), their role in addressing socioeconomic disparities is unknown. Our institution treats patients with CLTI at both traditional general vascular clinics and a multidisciplinary Limb Preservation Program (LPP). The LPP is in a minority community, providing expedited care at a single facility by a consistent team. We compared outcomes within the LPP with our institution's traditional clinics and explored patients' perspectives on barriers to care to evaluate if the LPP might address them. METHODS: All patients undergoing index revascularization for CLTI from 2014 to 2023 at our institution were stratified by clinic type (LPP or traditional). We collected clinical and socioeconomic variables, including Area Deprivation Index (ADI). Patient characteristics were compared using χ2, Student t, or Mood median tests. Outcomes were compared using log-rank and multivariable Cox analysis. We also conducted semi-structured interviews to understand patient-perceived barriers. RESULTS: From 2014 to 2023, 983 limbs from 871 patients were revascularized; 19.5% of limbs were treated within the LPP. Compared with traditional clinic patients, more LPP patients were non-White (43.75% vs 27.43%; P < .0001), diabetic (82.29% vs 61.19%; P < .0001), dialysis-dependent (29.17% vs 13.40%; P < .0001), had ADI in the most deprived decile (29.38% vs 19.54%; P = .0061), resided closer to clinic (median 6.73 vs 28.84 miles; P = .0120), and had worse Wound, Ischemia, and foot Infection (WIfI) stage (P < .001). There were no differences in freedom from death, major adverse limb event (MALE), or patency loss. Within the most deprived subgroup (ADI >90), traditional clinic patients had earlier patency loss (P = .0108) compared with LPP patients. Multivariable analysis of the entire cohort demonstrated that increasing age, heart failure, dialysis, chronic obstructive pulmonary disease, and increasing WIfI stage were independently associated with earlier death, and male sex was associated with earlier MALE. Ten traditional clinic patients were interviewed via convenience sampling. Emerging themes included difficulty understanding their disease, high visit frequency, transportation barriers, distrust of the health care system, and patient-physician racial discordance. CONCLUSIONS: LPP patients had worse comorbidities and socioeconomic deprivation yet had similar outcomes to healthier, less deprived non-LPP patients. The multidisciplinary clinic's structure addresses several patient-perceived barriers. Its proximity to disadvantaged patients and ability to conduct multiple appointments at a single visit may address transportation and visit frequency barriers, and the consistent team may facilitate patient education and improve trust. Including these elements in a multidisciplinary clinic and locating it in an area of need may mitigate some negative impacts of socioeconomic deprivation on CLTI outcomes.

Impact of wound management strategies after revascularization for chronic limb-threatening ischemia.

OBJECTIVE: There is no established consensus or guidelines for wound management after revascularization for patients with chronic limb-threatening ischemia (CLTI) without severe infection. This study is designed to evaluate the clinical effect of the wound management strategy on toe wounds after revascularization for CLTI. METHODS: This retrospective cohort study was performed at eight institutions affiliated with Keio University School of Medicine in Japan and included 261 patients who underwent revascularization for CLTI between April 2019 and July 2021. We identified 132 patients with toe wounds from the database who had restored in-line blood flow to the foot. Patients were divided into two groups by the timing of toe resection after revascularization, which dictated the wound management policy. Group A (62 patients) underwent early toe amputation for suspected osteomyelitis, whereas group B (70 patients) underwent watchful waiting. The primary outcome was wound healing after revascularization; the secondary outcome was major amputation. We compared outcomes between groups A and B after propensity score matching. RESULTS: Using propensity score matching, each patient in group A (33 patients) was matched with a patient in group B (33 patients). Wound healing in matched group A was significantly better than that in matched group B (respectively: 1-year wound healing rate: 90.0% vs 68.2%, P < .001; median wound healing time: 65 days vs 258 days, P < .01). Although five major amputations were necessary in matched group B, none were required in matched group A (P = .05). The high rate of major amputations in group B was attributed to the sudden exacerbation of infection. Limb salvage rate in matched group A exceeded matched group B (100.0% vs 90.5%: 1-year limb salvage rate, P = .02). CONCLUSIONS: Early toe amputation for highly suspected osteomyelitis in patients with CLTI with toe wounds may expedite wound healing compared with watchful waiting, potentially avoiding unnecessary major amputation. Considering the wound management strategy is crucial when evaluating wound healing outcomes in patients with CLTI with revascularization.

The association of comorbid depression with mortality and amputation risk in patients with chronic limb-threatening ischemia.

OBJECTIVE: There is increasing evidence that depression is a risk factor for worse outcomes in patients with peripheral artery disease. The association of depression in patients with chronic limb-threatening ischemia (CLTI) is not well described, nor is the impact of medical treatment for depression in this patient population. The objective of this study was to investigate the prevalence of depression in patients with CLTI, its association on major amputation and all-cause mortality, and whether medical antidepressant treatment is associated with improvement in these outcomes in patients with depression. METHODS: A retrospective review of all adult patients (≥18 years old) diagnosed with CLTI from January 1, 2007, to December 31, 2018, at a single academic medical center was performed. Collected data included patient demographics, comorbidities, and diagnosis of depression within 6 months of initial CLTI diagnosis. We also collected data on use of antidepressant medications. Outcomes evaluated were need for major lower extremity amputation and all-cause mortality. Multivariable logistic regression models estimated the adjusted effects of comorbid depression and antidepressant medication use on major amputation and all-cause mortality. Kaplan-Meier survival curves illustrated the probabilities of survival and limb salvage over time, stratified by diagnosis of comorbid depression. Multivariable Cox proportional hazards models estimated the adjusted effects of comorbid depression on time to major amputation and all-cause mortality, and the adjusted effect of antidepressant treatment on time to all-cause mortality. RESULTS: A total of 2987 patients with CLTI were identified. Mean age was 68.6 years (standard deviation, 12.9 years); 56.5% were male, and 43.5% were female. Comorbid depression within 6 months of CLTI diagnosis was present in 7.1% of the cohort (212 patients). In multivariable analysis, comorbid depression was associated with a 68% increase in the odds of major amputation (adjusted odds ratio [aOR], 1.68; 95% confidence interval [CI], 1.19-2.37; P < .01), a 164% increase in the odds of all-cause mortality among patients not taking antidepressants (aOR, 2.64; 95% CI, 1.31-5.32; P = .03), and only a 6% increase in the odds of all-cause mortality among patients taking antidepressants (aOR, 1.06; 95% CI, 0.72-1.55; P = .99). The effect of comorbid depression on mortality varied significantly by whether or not the patient was taking an antidepressant medication (P = .02). CONCLUSIONS: Comorbid depression in the patient population with CLTI is associated with a worse prognosis for major lower extremity amputation overall, and a worse prognosis for all-cause mortality among patients not taking an antidepressant. Furthermore, antidepressant treatment in the presence of comorbid depression in this patient population is associated with an improvement in the odds of all-cause mortality, illustrating the potential importance of medical management of depression.

Comparison of outcomes of percutaneous deep venous arterialization in multiple practice settings.

OBJECTIVE: We compared the efficacy of percutaneous deep venous arterialization (pDVA) in patients with no-option chronic limb-threatening ischemia in the hospital vs in office-based laboratory (OBL) settings. METHODS: A retrospective chart review was performed of all patients who underwent pDVA using off-the-shelf devices from January 2018 to March 2023 in a hospital and an OBL. We identified 73 eligible patients, 41 from a hospital setting (59% male; median age, 72 years; interquartile range, 18 years) and 32 from an OBL setting (59% males; 67 years; interquartile range, 16 years). All eligible patients were deemed to have no-option critical limb ischemia, had at least one patent proximal tibial artery available for the creation of an arteriovenous anastomosis, and were classified as having Rutherford classification IV or higher peripheral arterial disease. Patients were ineligible if classified as Rutherford classification III or lower, had active infection, did not have at least one appropriate venous target, and/or had rapidly progressing wounds requiring immediate major amputation. The primary outcome was major amputation-free survival (AFS). Secondary outcomes included technical success, limb salvage, survival, primary patency, reintervention rate, adverse events, and partial and complete wound healing. Outcomes were evaluated using Kaplan-Meier method, log-rank, and two-stage procedure tests. RESULTS: Technical success was achieved in 70 patients (96%) with 1 hospital (2.4%) and 2 OBL (6.3%) patients lost to follow-up. Major AFS estimates at 6 months, 1 year, and 2 years were 51.4%, 40.4%, and 30.2% in the hospital group and 69.4%, 54.0%, and 49.5% in the OBL group, respectively. Partial wound healing estimates at 6 months, 1 year, and 2 years were 27.5%, 71.7%, and 81.2% in the hospital group and 62.7% at all time points in the OBL group. Complete wound healing estimates at 6 months, 1 year, and 2 years were 6.7%, 33.3%, and 33.3% in the hospital group and 5.3%, 37.7%, and 41.6% in the OBL group, respectively. There was no significant difference in major AFS (P = .13), limb salvage (P = .07), survival (P = .69), primary patency (P = .53), partial (P = .08), or complete wound healing (P = .79) between groups. Reintervention was performed in 8 hospital (20.5%) and 14 OBL (45.2%) patients. CONCLUSIONS: pDVA is a feasible and safe procedure for no-option critical limb ischemia in the hospital and OBL setting without significant differences in outcomes at ≤2 years.

Outcomes of Prosthetic and Biological Grafts Compared to Arm Vein Grafts in Patients with Chronic Limb Threatening Ischemia.

OBJECTIVES: The optimal conduit for infrainguinal bypass (IIB) is single segment great saphenous vein (GSV). Unfortunately, GSV is not always available in patients with chronic limb threatening ischemia (CLTI). Other graft choices include arm vein grafts (AV), prosthetic grafts (PG) or biologic grafts (BG). Current data regarding the durability and limb salvage rates of those options is scarce, hence we aimed to investigate the impact of alternative graft types on post-operative and long-term outcomes on IIB in patients with CLTI. METHODS: The Vascular Quality Initiative (VQI) database was queried for patients undergoing IIB from January 2003 to April 2024. Patients were stratified into three groups: arm vein (cephalic, basilic), prosthetic grafts [Dacron, polytetrafluoroethylene (PTFE)], and biologic grafts (cadaveric, homograft, or xenograft). Saphenous vein grafts (greater and lesser saphenous) were excluded. Multivariate logistic regression analyzed postoperative outcomes: 30-day mortality, major adverse cardiovascular events (MACE), graft occlusion, prolonged length of stay >7days (PLOS), packed red blood cell (pRBC) transfusion >2 units, and infection. Cox Regression was used to report one-year outcomes: mortality, major amputation (above-ankle), and major adverse limb events (MALE defined as major amputation, thrombectomy or reintervention). RESULTS: A total of 9165 IIB procedures have been analyzed: AV 417 (4.55%); PG 7520 (82.05%); BG 1228 (13.40%). Compared to AV, patients receiving PG had higher odds of infection (aOR 2.89, p=0.045) and higher hazard of one-year mortality (aHR 1.51, p=0.035). On the other hand, patients receiving BG had higher risk of graft occlusion (aOR 4.55, p=0.040) and infection (aOR 2.78, p=0.046) as well higher hazard of one-year mortality (aHR 1.53, p=0.040), amputation (aHR 1.72, p=0.019) and amputation or death (aHR 1.52, p=0.005) compared to AV. After stratifying by bypass configuration, AV had the highest overall survival and amputation-free survival among the three alternative conduits in below-knee popliteal and tibial bypass targets. CONCLUSIONS: In this large multi-institutional study investigating alternative conduits to GSV, AV are found to be the most resistant to infections and are associated with the best overall survival and limb salvage outcomes compared to PG and BG particularly in below-knee distal targets. In cases where no GSV is available, AV and PG are acceptable alternatives with comparable one-year amputation-free survival and MALE-free survival rates. On the other hand, BG are associated with higher risk of graft occlusion and lower freedom from major amputation and death compared to AV.

Infra-inguinal bypass surgery vs endovascular revascularization for chronic limb-threatening ischemia in average- and high-risk patients.

OBJECTIVE: This study aimed to evaluate treatment outcomes after bypass surgery or endovascular therapy (EVT) in average- and high-risk patients with chronic limb-threatening ischemia (CLTI). METHODS: We retrospectively analyzed multicenter data of patients who underwent infra-inguinal revascularization for CLTI between 2015 and 2022. A high-risk patient was defined as one with estimated 30-day mortality rate ≥5% or 2-year survival rate ≤50%, as determined by the Surgical Reconstruction vs Peripheral Intervention in Patients With Critical Limb Ischemia (SPINACH) calculator. The amputation-free survival (AFS), limb salvage (LS), wound healing, and 30-day mortality were compared separately for the average- and high-risk patients between the bypass and EVT with propensity score matching. RESULTS: We analyzed 239 and 31 propensity score-matched pairs in the average- and high-risk patients with CLTI. In the average-risk patients, the 2-year AFS and LS rates were 78.1% and 94.4% in the bypass group and 63.0% and 87.7% in the EVT group (P < .001 and P = .007), respectively. The 1-year wound healing rates were 88.6% in the bypass group and 76.8% in the EVT group, respectively (P < .001). The 30-day mortality was 0.8% in the bypass surgery and 0.8% in the EVT group (P = .996). In the high-risk patients, there was no differences in the AFS, LS, and wound healing between the groups (P = .591, P = .148, and P = .074). The 30-day mortality was 3.2% in the bypass group and 3.2% in the EVT group (P = .991). CONCLUSIONS: Bypass surgery is superior to EVT with respect to the AFS, LS, and wound healing in the average-risk patients. EVT is a feasible first-line treatment strategy for high-risk patients with CLTI undergoing revascularization, based on the lack of significant differences in the 2-year AFS rate, between the bypass surgery and EVT cohorts.

Comparison of limb outcomes between bypass surgery and endovascular therapy in dialysis-dependent and -independent patients with chronic limb-threatening ischemia.

OBJECTIVE: To examine limb salvage (LS) and wound healing in dialysis-dependent and -independent patients with chronic limb-threatening ischemia (CLTI) after infrainguinal bypass surgery or endovascular therapy (EVT). METHODS: We retrospectively analyzed the multi-center data of patients who underwent infrainguinal revascularization for CLTI with Wound, Ischemia, and foot Infection (WIfI) stage 2 to 4 between 2015 and 2020. The primary endpoint was LS. The secondary endpoint included wound healing, amputation-free survival (AFS), periprocedural complications, and 2-year survival. Comparison of these outcomes were made after propensity score matching. RESULTS: We analyzed 252 dialysis-dependent (318 limbs) and 305 dialysis-independent (354 limbs) patients. Propensity score matching extracted 202 pairs with no significant differences in characteristics. The LS rate in bypass surgery was better than that in EVT in dialysis-dependent patients (P < .001). There was no significant difference in the LS rates between bypass surgery and EVT in dialysis-independent patients (P = .168). The wound healing rate of bypass surgery was better than that of EVT both dialysis-dependent and -independent patients with CLTI. The AFS rate of bypass surgery was better than that of EVT in dialysis-dependent patients (P < .001). There was no significant difference in the AFS rates between bypass surgery and EVT in dialysis-independent patients (P = .099). There was no significant difference in the occurrence of Clavien-Dindo ≥ IV and V between bypass surgery and EVT in dialysis-dependent and -independent patients. Age ≥75 years, serum albumin levels <3.5 g/dL, and non-ambulatory status were risk factors for 2-year mortality in dialysis-dependent patients. The 2-year survival rates in dialysis-dependent patients with risk factors of 0, 1, 2, and 3 were 82.5%, 67.1%, 49.5%, and 10.2%, respectively (P < .001). CONCLUSIONS: For LS and wound healing, bypass surgery was preferred for revascularization in dialysis-dependent patients with WIfI stage 2 to 4. Although dialysis dependency was one of the risk factors for 2-year mortality, dialysis-dependent patients, who have 0 to 1 risk factors, may benefit from bypass surgery, as 2-year survival of >50% is expected.

Influence of inframalleolar modifier P0/P1 on wound healing in bypass surgery vs endovascular therapy in patients with chronic limb-threatening ischemia.

OBJECTIVE: This study aimed to compare the influence of inframalleolar (IM) P0/P1 on wound healing in bypass surgery vs endovascular therapy (EVT) in patients with chronic limb-threatening ischemia (CLTI). METHODS: We retrospectively analyzed the multicenter data of patients who underwent infra-inguinal revascularization for CLTI between 2015 and 2022. IM P represents target artery crossing into foot, with intact pedal arch (P0) and absent or severely diseased pedal arch (P1). The endpoints were wound healing, limb salvage (LS), and postoperative complications. RESULTS: We analyzed 66 and 189 propensity score-matched pairs in the IM P0 and IM P1 cohorts, respectively. In the IM P0 cohort, the 1-year wound healing rates were 94.5% and 85.7% in the bypass surgery and EVT groups, respectively (P = .092), whereas those in the IM P1 cohort were 86.2% and 66.2% in the bypass surgery and EVT groups, respectively (P < .001). In the IM P0 cohort, the 2-year LS rates were 96.7% and 94.1% in the bypass surgery and EVT groups, respectively (P = .625), and those in the IM P1 cohort were 91.8% and 81.5% in the bypass surgery and EVT groups, respectively (P = .004). No significant differences were observed between the bypass surgery and EVT in terms of postoperative complication rates in either the IM P0 or P1 cohorts. CONCLUSIONS: Bypass surgery facilitated better wound healing and LS than EVT in patients with IM P1. Conversely, no differences in wound healing or LS were observed between groups in patients with IM P0. Bypass surgery should be considered a better revascularization strategy than EVT in patients with tissue loss and IM P1 disease.

Bioresorbable Scaffolds for Below-the-Knee Arterial Disease: A Literature Review of New Developments.

This review aimed to explore the therapeutic effect of bioabsorbable stents in the inferior genicular artery, from the emergence of absorbable bare metal stents to the latest technology in polymer and anti-proliferative eluting drugs mixed with coated bioresorbable vascular stents (BVSs). Currently, there are conflicting data regarding the safety and effectiveness of BVSs in infrapopliteal artery interventions, especially compared to the current generation of drug-eluting stents (DESs). This review will cover the existing data on BVSs in reconstructing the infrapopliteal arterial blood flow and active clinical trials for future iterations of BVSs. In terms of primary patency rate and target lesion revascularization rate, the available research on the effectiveness of BVSs in reconstructing the infrapopliteal arterial blood flow suggests that a BVS is compatible with current DESs within 3-12 months; long-term data have not yet been reported. The ABSORB BVS is the most studied BVS in cardiovascular disease (CAD). Initially, the ABSORB BVS showed promising results. Managing intricate regions in peripheral artery disorders, such as branching or lengthy lesions, continues to be a formidable undertaking. In contrast to the advanced narrowing of arteries seen in standard permanent stent procedures, bioabsorbable stents have the potential to promote the expansion and beneficial merging of blood channels in the latter stages. Furthermore, incorporating stents and re-establishing the endothelial function can diminish the probability of restenosis or thrombosis. Nevertheless, the extent to which bioabsorbable stents may simultaneously preserve arterial patency and guarantee their structural integrity remains uncertain. The powerful and intricate mechanical stresses exerted by the blood in the superficial femoral artery and popliteal artery can cause negative consequences on any implant inserted into the vessel, regardless of its composition, even metal. Furthermore, incorporating stents is advantageous for treating persistent occlusive lesions since it does not impact later treatments, including corrective bypass operations. Evidence is scarce about the use of bioabsorbable stents in treating infrapopliteal lesions. Utilizing bioabsorbable stents in minor infrapopliteal lesions can successfully maintain the patency of the blood vessel lumen, whereas balloon angioplasty cannot offer this benefit. The primary focus of testing these materials is determining whether bioabsorbable scaffolds can provide adequate radial force in highly calcified elongated lesions. Indeed, using "-limus" medication elution technology in conjunction with bioabsorbable stents has previously offered clinical benefits in treating the popliteal artery, as evidenced by limited trials.BVSs for peripheral arterial disease (PAD) show promise and have the potential to offer a less inflammatory and more vessel-friendly option compared to permanent metallic stents. However, current evidence does not yet allow for a universal recommendation for their use. Thus, ongoing, and future studies, such as those examining the newer generation of bioresorbable scaffolds (BRSs) with improved mechanical properties and resorption profiles, will be crucial in defining the role of BRSs in managing PAD.

Intravascular Lithotripsy for Peripheral Artery Calcification: 30-Day Outcomes From the Disrupt PAD III Observational Study.

PURPOSE: Intravascular lithotripsy (IVL) has shown promising safety and effectiveness in calcified peripheral artery disease (PAD) in large trials and small real-world experiences. Real-world evidence from a larger cohort is lacking, so we aimed to evaluate the real-world acute performance of IVL in the treatment of calcified PAD. MATERIALS AND METHODS: The Disrupt PAD III Observational Study (OS) is a prospective, multicenter, single-arm study. Patients with claudication or critical limb-threatening ischemia (CLTI) and at least moderate calcification were eligible. Independent predictors of procedural outcomes were assessed by multivariable analysis. RESULTS: Between November 2017 and June 2021 across 30 global sites, 1373 patients with 1677 lesions (1531, 91.3% core lab evaluable) were enrolled. Diameter stenosis and lesion length was 80.6±17.6% and 93.5±74.3 mm, respectively. Target vessels included femoropopliteal (61%), iliac (15.8%), common femoral (10.7%), and infrapopliteal arteries (12.8%). Lesion characteristics included 31.1% chronic total occlusions (CTOs) and 19.3% long lesions (≥15 cm). At final assessment, residual stenosis was 23.8±11.3%, with 0.9% serious angiographic complications, no abrupt closures, distal embolization, no flow, or thrombotic events. Independent predictors of ≤30% residual stenosis were lesion length ≥15 cm (odds ratio [OR]=0.384), female sex (OR=1.850), age ≤75 years (OR=1.625), IVL balloon to artery ratio ≥1.0 (OR=1.538), and CTO lesions (OR=0.638). Lesion length ≥15 cm (OR=16.076) was an independent predictor of procedural complications. CONCLUSIONS: The Disrupt PAD III OS represents the largest assessment of IVL periprocedural outcomes in calcified PAD. It confirmed excellent procedural safety and effectiveness in complex lesions across multiple peripheral vascular beds. CLINICAL IMPACT: This final analysis of the PAD III OS represents the largest report of peripheral IVL utilization in daily clinical practice. The outcomes of this study indicate that previously reported procedural results in clinical trial settings can be translated to a broader patient population. Treatment with peripheral IVL in severely calcified stenotic lower limb lesions demonstrated consistent acute safety and stenosis reduction, even in complex patients across multiple vessel beds. In addition, the importance of proper IVL balloon sizing to achieve excellent acute stenosis reduction was confirmed by multivariate analysis.

Short Term Outcomes of a Prospective Registry in Popliteal and Infrapopliteal Endovascular Interventions for Chronic Limb Threatening Ischaemia.

OBJECTIVE: The prevalence of chronic limb threatening ischaemia (CLTI) is increasing worldwide, resulting in the need for more patients undergoing revascularisation, especially for below the knee pathology. Nevertheless, prospective data on below the knee endovascular interventions are lacking. The aim of the study was to provide large scale, real world data on procedural and short term outcomes of popliteal and infrapopliteal endovascular interventions in patients with CLTI. METHODS: This study is an analysis of the first 1 000 interventions of the Dutch Chronic Lower Limb-Threatening Ischemia Registry (THRILLER). It includes all patients with CLTI undergoing popliteal or infrapopliteal endovascular revascularisation in seven hospitals in the Netherlands. The primary outcomes were limb salvage and amputation free survival (AFS) at three months estimated with the Kaplan-Meier method. Secondary outcomes were procedural complications and primary patency. RESULTS: Between February 2021 and July 2023, 1 000 endovascular procedures were performed in 840 patients (947 limbs), treating 486 popliteal and 1 209 tibial lesions. Wound, Ischemia, and foot Infection (WIfI) stages 1 - 4 were present in 16.8%, 17.2%, 25.4%, and 40.6% of the limbs, respectively. Technical success was hampered by arterial perforation, acute thrombosis, and distal embolisation in 8.7%, 1.0%, and 2.3% of the interventions, respectively. Limb salvage was 100.0%, 96.9%, 94.9%, and 86.1% (p < .001), whereas AFS was 96.9%, 93.2%, 86.6%, and 76.4% for WIfI stages 1 - 4 at three months (p < .001), respectively. Primary patency at the 6 - 8 week visit was 86.4% for popliteal and 74.3% for tibial lesions, respectively. CONCLUSION: THRILLER presents a large prospective database on outcomes of CLTI endovascular interventions. Popliteal and infrapopliteal endovascular revascularisation for CLTI is safe. Interventions with initial technical success have high rates of limb salvage and survival at three months. The WIfI classification provides a reliable instrument to predict limb salvage and AFS independently at three months.

Validation of JCLIMB, SPINACH, and VQI Calculators for Prediction of Two Year Survival in Patients With Chronic Limb Threatening Ischaemia After Infra-Inguinal Surgical or Endovascular Revascularisation.

OBJECTIVE: This study aimed to evaluate three survival prediction models: the JAPAN Critical Limb Ischaemia Database (JCLIMB), Surgical Reconstruction Versus Peripheral Intervention in Patients With Critical Limb Ischaemia (SPINACH), and Vascular Quality Initiative (VQI) calculators. METHODS: Multicentre data of patients who underwent infrainguinal revascularisation for chronic limb threatening ischaemia between 2018 and 2021 were analysed retrospectively. The prediction models were validated using a calibration plot analysis with the intercept and slope. The discrimination was evaluated using area under the curve (AUC) analysis. The observed two year overall survival (OS) was evaluated by the Kaplan - Meier method. The two year OS predicted by each model at < 50%, 50 - 70%, and > 70% was defined as high, medium, and low risk, respectively. RESULTS: A total of 491 patients who underwent infra-inguinal revascularisation were analysed. The rates of surgical revascularisation, endovascular therapy, and hybrid therapy were 26.5%, 70.1%, and 5.5%, respectively. The average age was 75.6 years, and the percentages of patients with diabetes mellitus and dialysis dependent end stage renal disease were 66.6% and 44.6%, respectively. The tissue loss rate was 85.7%. The intercept and slope were -0.13 and 1.18 for the JCLIMB, 0.11 and 0.82 for the SPINACH, and -0.15 and 1.10 for the VQI. The AUC for the two year OS of JCLIMB, SPINACH, and VQI were 0.758, 0.756, and 0.740, respectively. The observed two year OS rates of low, medium, and high risk using the JCLIMB calculator were 80.1%, 61.1%, and 28.5%, respectively (p < .001), using the SPINACH calculator were 81.0%, 57.0%, and 38.1%, respectively (p < .001), and using the VQI calculator were 77.8%, 45.8%, and 49.6%, respectively (p < .001). CONCLUSION: The JCLIMB, SPINACH, and VQI survival calculation models were useful, although the OS predicted by the VQI model appeared to be lower than the observed OS.

Clinical outcomes in patients with critical limb-threatening ischemia and infected ulcers following endovascular therapy are pathogen dependent: A single-center experience from 2012 to 2021.

BACKGROUND: Patients with critical limb-threatening ischemia (CLTI) and infected leg ulcers are at risk of amputation and postinterventional sepsis. METHODS: This retrospective, single-center study included patients with CLTI and infected leg ulcers who underwent endovascular treatment (EVT) between 2012 and 2021. RESULTS: The study included 712 patients, 286 (40.2%) of whom underwent amputation (minor, n = 212; major, n = 74). Gram-negative bacteria (GNB) were significantly more prevalent in amputees (36.4% vs 30.9%, p < 0.05). Patients with gram-positive bacteria (GPB) had a 4-year freedom from any amputation rate of 72% (95% CI 64-81%) compared to 52% (95% CI 42-66%) in patients with GNB identification (p < 0.05). Cox proportional regression analysis showed that GNB, male sex, mean Wound, Ischemia, and foot Infection (WIfI) score, diabetes mellitus, and end-stage renal disease were independently and positively associated with amputation (p < 0.05). The mean WIfI score and end-stage renal disease were independently and positively associated with death from any cause (p < 0.05). Staphylococcus aureus or GNB, end-stage renal disease, and diabetes mellitus were independent risk factors for sepsis after EVT (p < 0.05). Inpatient-administered antibiotic regimes had significantly higher microbiological activity in cases of GPB identification compared to GNB identification (28% vs 9%, p < 0.05). CONCLUSION: Although the isolation of both GNB and S. aureus is a risk factor for sepsis following EVT, the isolation of GNB is independently associated with higher rates of amputation, demonstrating the importance of identifying pathogens to recognize patients at high risk.

Evaluation of short-term mortality in patients with Medicare undergoing endovascular interventions for chronic limb-threatening ischemia.

INTRODUCTION: Patients with chronic limb-threatening ischemia (CLTI) have high mortality rates after revascularization. Risk stratification for short-term outcomes is challenging. We aimed to develop machine-learning models to rank predictive variables for 30-day and 90-day all-cause mortality after peripheral vascular intervention (PVI). METHODS: Patients undergoing PVI for CLTI in the Medicare-linked Vascular Quality Initiative were included. Sixty-six preprocedural variables were included. Random survival forest (RSF) models were constructed for 30-day and 90-day all-cause mortality in the training sample and evaluated in the testing sample. Predictive variables were ranked based on the frequency that they caused branch splitting nearest the root node by importance-weighted relative importance plots. Model performance was assessed by the Brier score, continuous ranked probability score, out-of-bag error rate, and Harrell's C-index. RESULTS: A total of 10,114 patients were included. The crude mortality rate was 4.4% at 30 days and 10.6% at 90 days. RSF models commonly identified stage 5 chronic kidney disease (CKD), dementia, congestive heart failure (CHF), age, urgent procedures, and need for assisted care as the most predictive variables. For both models, eight of the top 10 variables were either medical comorbidities or functional status variables. Models showed good discrimination (C-statistic 0.72 and 0.73) and calibration (Brier score 0.03 and 0.10). CONCLUSION: RSF models for 30-day and 90-day all-cause mortality commonly identified CKD, dementia, CHF, need for assisted care at home, urgent procedures, and age as the most predictive variables as critical factors in CLTI. Results may help guide individualized risk-benefit treatment conversations regarding PVI.

Competing risk analysis to estimate amputation incidence and risk in lower-extremity peripheral artery disease.

Background: Patients with peripheral artery disease face high amputation and mortality risk. When assessing vascular outcomes, consideration of mortality as a competing risk is not routine. We hypothesize standard time-to-event methods will overestimate major amputation risk in chronic limb-threatening ischemia (CLTI) and non-CLTI. Methods: Patients undergoing peripheral vascular intervention from 2017 to 2018 were abstracted from the Vascular Quality Initiative registry and stratified by mean age (⩾ 75 vs < 75 years). Mortality and amputation data were obtained from Medicare claims. The 2-year cumulative incidence function (CIF) and risk of major amputation from standard time-to-event analysis (1 - Kaplan-Meier and Cox regression) were compared with competing risk analysis (Aalen-Johansen and Fine-Gray model) in CLTI and non-CLTI. Results: A total of 7273 patients with CLTI and 5095 with non-CLTI were included. At 2-year follow up, 13.1% of patients underwent major amputation and 33.4% died without major amputation in the CLTI cohort; 1.3% and 10.7%, respectively, in the non-CLTI cohort. In CLTI, standard time-to-event analysis overestimated the 2-year CIF of major amputation by 20.5% and 13.7%, respectively, in patients ⩾ 75 and < 75 years old compared with competing risk analysis. The standard Cox regression overestimated adjusted 2-year major amputation risk in patients ⩾ 75 versus < 75 years old by 7.0%. In non-CLTI, the CIF was overestimated by 7.1% in patients ⩾ 75 years, and the adjusted risk was overestimated by 5.1% compared with competing risk analysis. Conclusions: Standard time-to-event analysis overestimates the incidence and risk of major amputation, especially in CLTI. Competing risk analyses are alternative approaches to estimate accurately amputation risk in vascular outcomes research.

Safety and effectiveness of the Phoenix atherectomy device for endovascular treatment of common femoral and popliteal arteries: Results of the EN-MOBILE trial.

Background: This study aimed to assess the peri- and postprocedural outcomes of atherectomy-assisted endovascular treatment of the common femoral (CFA) and popliteal arteries. Methods: Phoenix atherectomy was used for the treatment of 73 and 53 de novo CFA and popliteal artery lesions, respectively, in 122 consecutive patients. Safety endpoints encompassed perforation and peripheral embolization. Postprocedural endpoints included freedom from clinically driven target lesion revascularization (CD-TLR) and clinical success (an improvement of ⩾ 2 Rutherford category [RC]). In addition, 531 patients treated for popliteal artery stenosis or occlusion without atherectomy were used as a comparator group. Results: Procedural success (residual stenosis < 30% after treatment) was 99.2%. The need for bail-out stenting was 2 (2.7%) and 3 (5.7%) in CFA and popliteal artery lesions, respectively. Only one (1.4%) embolization occurred in the CFA, which was treated by catheter aspiration. No perforations occurred. After 1.50 (IQR = 1.17-2.20) years, CD-TLR occurred in seven (9.2%) and six (14.6%) patients with CFA and popliteal artery lesions, respectively, whereas clinical success was achieved in 62 (91.2%) and 31 (75.6%), respectively. Patients treated with atherectomy and DCB in the popliteal artery after matching for baseline RC, lesion calcification, length, and the presence of chronic total occlusion, exhibited higher freedom from CD-TLR compared to the nondebulking group (HR = 3.1; 95% CI = 1.1-8.5, p = 0.03). Conclusion: Atherectomy can be used safely and is associated with low rates of bail-out stenting in CFA and popliteal arteries. CD-TLR and clinical success rates are clinically acceptable. In addition, for the popliteal artery, atherectomy combined with DCB demonstrates lower CD-TLR rates compared to a DCB alone strategy. (German Clinical Trials Register: DRKS00016708).

Accuracy of maximal acceleration time of pedal arteries to diagnose critical limb-threatening ischemia.

INTRODUCTION: Maximal acceleration time of distal arteries of the foot (ATmax) is correlated to ankle-brachial index (ABI) and toe-brachial index (TBI), and seems very promising in diagnosing severe peripheral artery disease (PAD) and especially critical limb-threatening ischemia (CLTI). Our goal was to confirm the cut-off value of 215 ms to predict a toe pressure (TP) ⩽ 30 mmHg. METHODS: A 4-month retrospective study was conducted on patients addressed for suspicion of PAD. Demographic data, ABI, TBI, and Doppler ultrasound scanning parameters of the dorsal pedis and lateral plantar arteries (DPA and LPA) were recorded. RESULTS: A total of 137 patients with 258 lower limbs were included. ATmax was highly correlated to TBI (r = -0.89, p < 0.001). With the cut-off value of 215 ms, ATmax was effective to diagnose TP ⩽ 30 mmHg with a sensitivity of 93% [95% CI 77-99], a specificity of 96% [95% CI 92-98], a positive predictive value of 73% [95% CI 56-86], a negative predictive value of 99% [95% CI 97-100], and an area under the receiver operating characteristics curve of 0.99 [95% CI 0.98-1.00]. ATmax also showed promising results to rule out PAD in healthy patients. CONCLUSION: ATmax is a reliable diagnostic tool to diagnose low TP and could be a new easily performed hemodynamic criterion for diagnosis of CLTI.

Five-year outcomes of the GORE VIABAHN Endoprosthesis for the treatment of complex femoropopliteal lesions from a Japanese postmarket surveillance study.

Introduction: The safety and effectiveness of the GORE VIABAHN Endoprosthesis for treatment of symptomatic patients with peripheral artery disease (PAD) and complex femoropopliteal (FP) lesions was assessed in a real-world Japanese practice setting. Methods: A prospective, multicenter, postmarket surveillance study was conducted from 2016 to 2017 at 64 sites in Japan. Symptomatic patients with PAD and FP lesions ⩾ 10 cm and reference vessel diameters ranging from 4.0 to 7.5 mm were eligible for enrollment. Outcome measures evaluated at 5 years were primary patency (PP), primary-assisted patency (PAP), secondary patency (SP), freedom from target lesion revascularization (fTLR), occurrence of device- or procedure-related serious adverse events (SAEs), and stent fractures. Results: A total of 321 patients were enrolled and were a mean age of 73.9 ± 8.7 years; 77.3% were men and 26.5% had chronic limb-threatening ischemia (CLTI). The mean lesion length was 23.6 ± 6.6 cm and the frequency with TASC II C/D lesions and chronic total occlusions was 86.6% and 70.4%, respectively. The Kaplan-Meier estimated PP, PAP, SP, and fTLR at 5 years was 62.4%, 74.1%, 82.3%, and 75.9%, respectively. The mean ankle-brachial index was 0.92 ± 0.15 and the mean improvement in Rutherford class was 2.3 ± 1.4, which was maintained through 5 years. The rate of cumulative device- or procedure-related SAEs through 5 years was 19.9% with only 9.3% of those occurring after the first year. No stent fractures were observed through 5 years by x-ray evaluation. Conclusion: The 5-year safety and efficacy outcomes of the endoprosthesis were clinically acceptable for treating complex FP lesions in a real-world cohort of Japanese patients with PAD. (ClinicalTrials.gov Identifier: NCT04706273).

Comparison of endovascular infrapopliteal revascularisation strategies based on the angiosome model in diabetics with CLTI.

Background: Infrapopliteal endovascular interventions (EVT) strategies in diabetic patients are still in debate because the lesions are more likely to be diffuse with a different pattern of collateral arteries ranging from reduced to normal caliber. The aim of this all-comers study was to analyse the outcome of two different infrapopliteal EVT strategies (Group I: angiosome-based direct revascularization - DR vs. Group II: complete (direct + indirect) revascularization strategy - CR) in diabetic patients with chronic limb-threatening ischemia (CLTI) in 2 time-periods. Furthermore we analysed the outcome if DR or CR failed and only indirect revascularization (IR) or no revascularization was possible. Both groups were differentiated in patients with collaterals, defined as an intact pedal arch (immediate or after pedal PTA). Patients and methods: The database includes 91 consecutive EVT with two intrapopliteal interventional strategies performed in 68 diabetic patients (pts. 24 female, 44 male, mean age 73±10 years) between 2013-2016 and 2017-2022. Positive clinical outcome was defined as wound healing with or w/o minor amputation, combined with a symptom improvement to Rutherford category 0 or 1 after 6 months. The clinical outcome proportions were compared using the Fisher's exact test. Results: Successful DR (59%) and successful CR (47%) strategy demonstrated a similar positive clinical outcome (92.6% vs. 90.5%; p=0.594). Indirect revascularization (Group I: 26%; Group II: 44%) showed a significantly lower positive outcome in comparison to a successful DR as well as CR strategy (33.3% vs. 92.6%, p=0.0003; 40% vs 90.5%, p=0.001). IR outcome improved by the presence of collaterals (66.7% vs. 30.8%). Conclusions: In case of successful intervention, both strategies (DR and CR) yielded a similarly high proportion of positive clinical outcome. The role of collaterals and the pedal arch on the clinical outcome are important in patients in whom only IR was possible.

A systematic review of the neutrophil to lymphocyte and platelet to lymphocyte ratios in patients with lower extremity arterial disease.

Lower extremity arterial disease (LEAD) is caused by atherosclerotic plaque in the arterial supply to the lower limbs. The neutrophil to lymphocyte and platelet to lymphocyte ratios (NLR, PLR) are established markers of systemic inflammation which are related to inferior outcomes in multiple clinical conditions, though remain poorly described in patients with LEAD. This review was carried out in accordance with PRISMA guidelines. The MEDLINE database was interrogated for relevant studies. Primary outcome was the prognostic effect of NLR and PLR on clinical outcomes following treatment, and secondary outcomes were the prognostic effect of NLR and PLR on disease severity and technical success following revascularisation. There were 34 studies included in the final review reporting outcomes on a total of 19870 patients. NLR was investigated in 21 studies, PLR was investigated in two studies, and both NLR & PLR were investigated in 11 studies. Relating to increased levels of systemic inflammation, 20 studies (100%) reported inferior clinical outcomes, 13 (92.9%) studies reported increased disease severity, and seven (87.5%) studies reported inferior technical results from revascularisation. The studies included in this review support the role of elevated NLR and PLR as key components influencing the clinical outcomes, severity, and success of treatment in patients with LEAD. The use of these easily accessible, cost effective and routinely available markers is supported by the present review.