Transcatheter Arterialization of Deep Veins in Chronic Limb-Threatening Ischemia.

BACKGROUND: Approximately 20% of patients with chronic limb-threatening ischemia have no revascularization options, leading to above-ankle amputation. Transcatheter arterialization of the deep veins is a percutaneous approach that creates an artery-to-vein connection for delivery of oxygenated blood by means of the venous system to the ischemic foot to prevent amputation. METHODS: We conducted a prospective, single-group, multicenter study to evaluate the effect of transcatheter arterialization of the deep veins in patients with nonhealing ulcers and no surgical or endovascular revascularization treatment options. The composite primary end point was amputation-free survival (defined as freedom from above-ankle amputation or death from any cause) at 6 months, as compared with a performance goal of 54%. Secondary end points included limb salvage, wound healing, and technical success of the procedure. RESULTS: We enrolled 105 patients who had chronic limb-threatening ischemia and were of a median age of 70 years (interquartile range, 38 to 89). Of the patients enrolled, 33 (31.4%) were women and 45 (42.8%) were Black, Hispanic, or Latino. Transcatheter arterialization of the deep veins was performed successfully in 104 patients (99.0%). At 6 months, 66.1% of the patients had amputation-free survival. According to Bayesian analysis, the posterior probability that amputation-free survival at 6 months exceeded a performance goal of 54% was 0.993, which exceeded the prespecified threshold of 0.977. Limb salvage (avoidance of above-ankle amputation) was attained in 67 patients (76.0% by Kaplan-Meier analysis). Wounds were completely healed in 16 of 63 patients (25%) and were in the process of healing in 32 of 63 patients (51%). No unanticipated device-related adverse events were reported. CONCLUSIONS: We found that transcatheter arterialization of the deep veins was safe and could be performed successfully in patients with chronic limb-threatening ischemia and no conventional surgical or endovascular revascularization treatment options. (Funded by LimFlow; PROMISE II study ClinicalTrials.gov number, NCT03970538.).

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 direct oral anticoagulants and warfarin in chronic limb-threatening ischemia.

OBJECTIVE: The role of direct oral anticoagulants (DOACs) in chronic limb-threatening ischemia after revascularization is unknown. Current evidence-based guidelines do not provide clear guidance on the role of anticoagulation or the selection of anticoagulant. Current practice is highly varied and based on provider and patient preference. The purpose of this study was to measure the impact of different anticoagulants on the incidence of major adverse limb events (MALEs) after revascularization for chronic limb-threatening ischemia, major adverse cardiovascular events (MACEs), all-cause mortality, and hospitalization for major bleeding events. METHODS: This was a single-center, observational, retrospective cohort study. Subjects were eligible if they were 18 years or older; underwent endovascular or open revascularization for chronic limb-threatening ischemia, rest pain, or tissue loss; and were subsequently prescribed apixaban, rivaroxaban, or warfarin. The primary end point was the incidence of MALEs, including above-ankle amputation or major index-limb reintervention, within 1 year of index event. Secondary end points included the rate of all-cause mortality, MACEs, and incidence of International Society on Thrombosis and Haemostasis (ISTH) major bleeding. RESULTS: From January 1, 2017, to September 20, 2022, 141 patients met the inclusion and exclusion criteria and were reviewed. The median age was 67 years, with 92 patients prescribed apixaban or rivaroxaban and 49 patients prescribed warfarin. Of these, 42 patients were prescribed triple antithrombotic therapy, 88 dual antithrombotic therapy, and 13 anticoagulant monotherapy. The primary outcome of 1-year MALEs occurred in 36.7% of the warfarin group and 33.7% of the DOAC group (relative risk [RR], 1.09; 95% CI, 0.53-2.25; P = .72). Secondary outcomes of 1-year MACEs (10.2% vs 4.3%; RR, 2.35; 95% CI, 0.60-9.18; P = .18) and 1-year all-cause mortality (26.5% vs 16.3%; RR, 1.63; 95% CI, 0.70-3.78; P = .15) did not differ between the groups. The secondary safety outcome of 1-year ISTH major bleeding occurred in 16.3% of the warfarin group and 4.3% of the DOAC group (RR, 3.76; 95% CI, 1.07-13.19; P = .015). CONCLUSIONS: In patients with chronic limb-threatening ischemia who were revascularized and prescribed anticoagulation with apixaban, rivaroxaban, or warfarin on discharge, no difference in MALEs, MACEs, or all-cause mortality was found. However, 1-year admissions for ISTH major bleeding were significantly higher among patients prescribed warfarin. A randomized trial may confirm these findings.

Surgery or endovascular therapy for patients with chronic limb-threatening ischemia requiring infrapopliteal interventions.

OBJECTIVE: The recent publication of randomized trials comparing open bypass surgery to endovascular therapy in patients with chronic limb-threatening ischemia, namely, Best Endovascular vs Best Surgical Therapy in Patients with Critical Limb Ischemia (BEST-CLI) and Bypass versus Angioplasty in Severe Ischaemia of the Leg-2 (BASIL-2), has resulted in potentially contradictory findings. The trials differed significantly with respect to anatomical disease patterns and primary end points. We performed an analysis of patients in BEST-CLI with significant infrapopliteal disease undergoing open tibial bypass or endovascular tibial interventions to formulate a relevant comparator with the outcomes reported from BASIL-2. METHODS: The study population consisted of patients in BEST-CLI with adequate single segment saphenous vein conduit randomized to open bypass or endovascular intervention (cohort 1) who additionally had significant infrapopliteal disease and underwent tibial level intervention. The primary outcome was major adverse limb event (MALE) or all-cause death. MALE included any major limb amputation or major reintervention. Outcomes were evaluated using Cox proportional regression models. RESULTS: The analyzed subgroup included a total of 665 patients with 326 in the open tibial bypass group and 339 in the tibial endovascular intervention group. The primary outcome of MALE or all-cause death at 3 years was significantly lower in the surgical group at 48.5% compared with 56.7% in the endovascular group (P = .0018). Mortality was similar between groups (35.5% open vs 35.8% endovascular; P = .94), whereas MALE events were lower in the surgical group (23.3% vs 35.0%; P<.0001). This difference included a lower rate of major reinterventions in the surgical group (10.9%) compared with the endovascular group (20.2%; P = .0006). Freedom from above ankle amputation or all-cause death was similar between treatment arms at 43.6% in the surgical group compared with 45.3% the endovascular group (P = .30); however, there were fewer above ankle amputations in the surgical group (13.5%) compared with the endovascular group (19.3%; P = .0205). Perioperative (30-day) death rates were similar between treatment groups (2.5% open vs 2.4% endovascular; P = .93), as was 30-day major adverse cardiovascular events (5.3% open vs 2.7% endovascular; P = .12). CONCLUSIONS: Among patients with suitable single segment great saphenous vein who underwent infrapopliteal revascularization for chronic limb-threatening ischemia, open bypass surgery was associated with a lower incidence of MALE or death and fewer major amputation compared with endovascular intervention. Amputation-free survival was similar between the groups. Further investigations into differences in comorbidities, anatomical extent, and lesion complexity are needed to explain differences between the BEST-CLI and BASIL-2 reported outcomes.

Endovascular therapy versus bypass for chronic limb-threatening ischemia in a real-world practice.

OBJECTIVE: The recent Best Endovascular vs Best Surgical Therapy in Patients with Critical Limb Ischemia (BEST-CLI) study showed that bypass was superior to endovascular therapy (ET) in patients with chronic limb-threatening ischemia (CLTI) deemed suitable for either approach who had an available single-segment great saphenous vein (GSV). However, the superiority of bypass among those lacking GSV was not established. We aimed to examine comparative treatment outcomes from a real-world CLTI population using the Vascular Quality Initiative-Medicare-linked database. METHODS: We queried the Vascular Quality Initiative-Medicare-linked database for patients with CLTI who underwent first-time lower extremity revascularization (2010-2019). We performed two one-to-one propensity score matchings (PSMs): ET vs bypass with GSV (BWGSV) and ET vs bypass with a prosthetic graft (BWPG). The primary outcome was amputation-free survival. Secondary outcomes were freedom from amputation and overall survival (OS). RESULTS: Three cohorts were queried: BWGSV (N = 5279, 14.7%), BWPG (N = 2778, 7.7%), and ET (N = 27,977, 77.6%). PSM produced two sets of well-matched cohorts: 4705 pairs of ET vs BWGSV and 2583 pairs of ET vs BWPG. In the matched cohorts of ET vs BWGSV, ET was associated with greater hazards of death (hazard ratio [HR] = 1.34, 95% confidence interval [CI], 1.25-1.43; P < .001), amputation (HR = 1.30, 95% CI, 1.17-1.44; P < .001), and amputation/death (HR = 1.32, 95% CI, 1.24-1.40; P < .001) up to 4 years. In the matched cohorts of ET vs BWPG, ET was associated with greater hazards of death up to 2 years (HR = 1.11, 95% CI, 1.00-1.22; P = .042) but not amputation or amputation/death. CONCLUSIONS: In this real-world multi-institutional Medicare-linked PSM analysis, we found that BWGSV is superior to ET in terms of OS, freedom from amputation, and amputation-free survival up to 4 years. Moreover, BWPG was superior to ET in terms of OS up to 2 years. Our study confirms the superiority of BWGSV to ET as observed in the BEST-CLI trial.

Comparison of mortality and amputation after lower extremity bypass versus peripheral vascular intervention in patients with chronic limb-threatening ischemia and comorbid chronic kidney disease.

OBJECTIVE: Comorbid chronic kidney disease (CKD) is associated with worse outcomes for patients with chronic limb-threatening ischemia (CLTI). However, comparative effectiveness data are limited for lower extremity bypass (LEB) vs peripheral vascular intervention (PVI) in patients with CLTI and CKD. We aimed to evaluate (1) 30-day all-cause mortality and amputation and (2) 5-year all-cause mortality and amputation for LEB vs PVI in patients with comorbid CKD. METHODS: Individuals who underwent LEB and PVI were queried from the Vascular Quality Initiative with Medicare claims-linked outcomes data. Propensity scores were calculated using 13 variables, and a 1:1 matching method was used. The mortality risk at 30 days and 5 years in LEB vs PVI by CKD was assessed using Kaplan-Meier and Cox proportional hazards models, with interaction terms added for CKD. For amputation, cumulative incidence functions and Fine-Gray models were used to account for the competing risk of death, with interaction terms for CKD added. RESULTS: Of 4084 patients (2042 per group), the mean age was 71.0 ± 10.8 years, and 69.0% were male. Irrespective of CKD status, 30-day mortality (hazard ratio [HR]: 0.94, 95% confidence interval [CI]: 0.63-1.42, P = .78) was similar for LEB vs PVI, but LEB was associated with a lower risk of 30-day amputation (sub-HR [sHR]: 0.66, 95% CI: 0.44-0.97, P = .04). CKD status, however, did not modify these results. Similarly, LEB vs PVI was associated with a lower risk of 5-year mortality (HR: 0.79, 95% CI: 0.71-0.88, P < .001) but no difference in 5-year amputation (sHR: 1.03, 95% CI: 0.89-1.20, P = .67). CKD status did not modify these results. CONCLUSIONS: Regardless of CKD status, patients had a lower risk of 5-year all-cause mortality and 30-day amputation with LEB vs PVI. Results may help inform preference-sensitive treatment decisions on LEB vs PVI for patients with CLTI and CKD, who may commonly be deemed too high risk for surgery.

Descriptive Analysis of Amputation-Free Survival After First Time Infra-Inguinal Bypass Occlusion.

INTRODUCTION: Occlusion after infra-inguinal bypass surgery for peripheral artery disease is a major complication with potentially devastating consequences. In this descriptive analysis, we sought to describe the natural history and explore factors associated with long-term major amputation-free survival following occlusion of a first-time infra-inguinal bypass. METHODS: Using a prospective database from a tertiary care vascular center, we conducted a retrospective cohort study of all patients with peripheral artery disease who underwent a first-time infra-inguinal bypass and subsequently suffered a graft occlusion (1997-2021). The primary outcome was longitudinal rate of major amputation-free survival after bypass occlusion. Cox proportional hazard models were used to generate hazard ratios (HRs) and 95% confidence intervals (CIs) to explore predictors of outcomes. RESULTS: Of the 1318 first-time infra-inguinal bypass surgeries performed over the study period, 255 bypasses occluded and were included in our analysis. Mean age was 66.7 (12.6) years, 40.4% were female, and indication for index bypass was chronic limb threatening ischemia (CLTI) in 89.8% (n = 229). 48.2% (n = 123) of index bypass conduits used great saphenous vein, 29.0% (n = 74) prosthetic graft, and 22.8% (n = 58) an alternative conduit. Median (interquartile range) time to bypass occlusion was 6.8 (2.3-19.0) months, and patients were followed for median of 4.3 (1.7-8.1) years after bypass occlusion. Following occlusion, 38.04% underwent no revascularization, 32.94% graft salvage procedure, 25.1% new bypass, and 3.92% native artery recanalization. Major amputation-free survival following occlusion was 56.9% (50.6%-62.8%) at 1 y, 37.1% (31%-43.3%) at 5 y, and 17.2% (11.9%-23.2%) at 10 y. In multivariable analysis, factors associated with lower amputation-free survival were older age, female sex, advanced cardiorenal comorbidities, CLTI at index procedure, CLTI at time of occlusion, and distal index bypass outflow. Initial treatment after occlusion with both a new surgical bypass (HR 0.44, CI: 0.29-0.67) or a graft salvage procedure (HR 0.56, CI: 0.38-0.82) showed improved amputation-free survival. One-year rate of major amputation or death were 59.8% (50.0%-69.6%) for those who underwent no revascularization, 37.9% (28.7%-49.0%) for graft salvage, and 26.7% (17.6%-39.5%) for new bypass. CONCLUSIONS: Long-term major amputation-free survival is low after occlusion of a first-time infra-inguinal bypass. While several nonmodifiable risk factors were associated with lower amputation-free survival, treatment after graft occlusion with either a new bypass or a graft salvage procedure may improve longitudinal outcomes.

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.

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.

Treatment Outcomes in Octogenarians with Chronic Limb-Threatening Ischemia after Infrainguinal Bypass Surgery or Endovascular Therapy.

BACKGROUND: This study aimed to analyze the clinical outcomes after revascularization for chronic limb-threatening ischemia (CLTI) in patients aged ≥ 80 years and < 80 years. METHODS: We retrospectively analyzed multicenter data of 789 patients who underwent infrainguinal revascularization for CLTI between 2015 and 2021. The end points were 2-year overall survival (OS), amputation-free survival (AFS), limb salvage (LS), and postoperative complications. RESULTS: A total of 90 patients aged ≥ 80 years and 200 patients aged < 80 years underwent bypass surgery (BSX), and 205 patients aged ≥ 80 years and 294 patients aged < 80 years underwent endovascular therapy (EVT). Before the propensity score matching, multivariate analyses showed that age ≥ 80 years, lower body mass index and serum albumin levels, nonambulatory status, and end-stage renal disease were independent risk factors for 2-year mortality in the BSX and EVT groups. After propensity score matching, the 2-year OS was better in the < 80 years cohort than in the ≥ 80 years cohort in both the BSX and EVT groups (P = 0.018 and P = 0.035, respectively). There was no difference in the 2-year LS rates between the < 80 years and the ≥ 80 years cohorts in both the BSX and EVT groups (P = 0.621 and P = 0.287, respectively). According to the number of risk factors, except for age ≥ 80 years, there was no difference in the 2-year AFS rates between the < 80 years and ≥ 80 years cohorts for the BSX and EVT groups with 0-1 risk factor (P = 0.957 and P = 0.655, respectively). However, the 2-year AFS rate was poor, especially in the ≥ 80 years cohort in the BSX with 2-4 risk factors (P = 0.015). The Clavien-Dindo ≥ IV complication rates tended to be higher in the ≥ 80 years cohort than in the < 80 years cohort only in the BSX with 2-4 risk factors (P = 0.056). CONCLUSIONS: Patients with CLTI aged ≥ 80 years had poorer OS than those aged < 80 years. However, there was no difference in LS between the ≥ 80 years and < 80 years cohorts in both the BSX and EVT groups. Although age ≥ 80 years was associated with poorer OS, patients with 0-1 risk factor may benefit from revascularization, including BSX, because no difference was observed in AFS or Clavien-Dindo ≥ IV complications.

Long-Term Outcome of Lower Extremity Bypass Surgery in Patients with Chronic Kidney Disease and Critical Limb Ischemia in Germany.

BACKGROUND: The aim of this study is to present short- and long-term outcomes after lower extremity bypass (LEB) surgery in patients with chronic limb-threatening ischemia and chronic kidney disease (CKD), differentiated by peripheral artery disease (PAD) Fontaine stage III and IV. METHODS: Retrospective analysis of anonymized data from a nationwide German health insurance company (AOK). Data from 22,633 patients (14,523 men) who underwent LEB from 2010 to 2015 were analyzed, presenting 18,271 with CKD stage 1/2, 2,483 patients with CKD stage 3, and 1,879 with CKD stage 4/5. RESULTS: Perioperative mortality (60-day mortality) was 7.2% for CKD stage 1/2, 12.4% for CKD stage 3, and 19.8% for CKD stage 4/5. Patients with PAD stage IV had significantly higher perioperative mortality (10.3%) than patients with PAD stage III (4.5%). The perioperative major amputation rate depended significantly on PAD stage IV (odds ratio [OR]: 2.57 confidence interval [CI]: 2.16-3.05, P < 0.001), the LEB level below the knee and crural/pedal (OR: 2.49 CI: 2.14-2.90, P < 0.001), CKD stage 4/5 (OR: 1.28, CI: 1.06-1.54, P = 0.009), and the presence of diabetes mellitus type 2 (OR: 1.19, CI: 1.05-1.36, P = 0.007). Kaplan-Meier estimated long-term survival of up to 9 years after surgery was 31.7% for patients with CKD stage 1 and 2, 14.3% for CKD stage 3, and only 10.1% for CKD stage 4 and 5 (P < 0.001). PAD Fontaine stage IV versus III (hazard ratio: 1.64, CI: 1.56-1.71, P < 0.001), but not bypass level, had an independent adverse influence on long-term survival. CONCLUSION: CKD and PAD stage were equally significant independent predictors of patient survival and major adverse cardiovascular events with higher PAD and CKD stages associated with less favorable long-term outcomes.

The Modified Albumin-Bilirubin (ALBI) Grade Reflect the Fate of Limb Prognosis in Patients with Chronic Limb-Threatening Ischemia.

BACKGROUND: To examine the influence of liver function on patients with chronic limb-threatening ischemia (CLTI), we classified patients with CLTI after revascularization according to their modified albumin-bilirubin (ALBI) grades. METHODS: We retrospectively analyzed single-center data of patients who underwent revascularization for CLTI between 2015 and 2020. Patients were classified with ALBI grades 1, 2a, and 2b and 3 according to the ALBI score, which was calculated, based on serum albumin and total bilirubin levels. The endpoints were the 2-year amputation-free survival (AFS) and 1-year wound healing rates. RESULTS: We included 190 limbs in 148 patients, and 50, 54, and 86 cases were assigned as grade 1, 2a, and 2b and 3, respectively. The 2-year AFS rates for the grade 1, 2a, and 2b and 3 groups were 79 ± 6%, 66% ± 7%, and 45 ± 6%, respectively (P < 0.01). One-year cumulative wound healing rates for grade 1, 2a, and 2b and 3 groups were 68 ± 7%, 69% ± 6%, and 48% ± 5%, respectively (P = 0.01). Multivariate Cox proportional hazard analyses identified age (≥75 years), dependent ambulatory status, and modified ALBI grades 2b and 3 compared with grades 1 and 2a as significant independent predictors of AFS. The dependent ambulatory status and Wound, Ischemia, and foot Infection classification stage 4 were significant negative predictors of wound healing. CONCLUSIONS: Many patients with CLTI had high modified ALBI grades, and impaired liver function classified as modified ALBI grade 2b and 3 is a robust negative predictor of AFS.

Association of Sarcopenia With Mortality in Patients With Chronic Limb-Threatening Ischemia Undergoing Endovascular Revascularization.

INTRODUCTION: Chronic limb-threatening ischemia (CLTI) is the most severe form of peripheral artery disease and leads high mortality. Sarcopenia, characterized by the loss of muscle mass or poor muscle quality, is associated with adverse clinical outcomes. This study aimed to investigate the association between sarcopenia and the long-term outcomes in patients with CLTI after endovascular revascularization. METHODS: We retrospectively reviewed the medical records of all patients with CLTI who underwent endovascular revascularization between January 2015, and December 2021. The skeletal muscle area was calculated at the third lumbar vertebra from computed tomography images using the manual trace method and normalized to patient height. Sarcopenia was defined as a third lumbar skeletal muscle index of <40.8 cm2/m2 in males and <34.9 cm2/m2 in females. The Kaplan-Meier and Cox proportional hazards regression analyses were used for survival analysis and to evaluate the association between sarcopenia and mortality. RESULTS: A total of 137 patients (90 men; mean age 71.7 ± 9.6 y) were enrolled for the study, of whom 56 (40.8%) had sarcopenia. The 3-year overall survival rate in patients with CLTI who underwent endovascular revascularization was 71.2%. The sarcopenic group had a significantly worse 3-year overall survival rate than the nonsarcopenic group (55.3% versus 78.6%, P = 0.001). Multivariate Cox proportional hazard regression analyses revealed that sarcopenia (hazard ratio, 2.262; 95% confidence interval, 1.132-4.518; P = 0.021) and dialysis (hazard ratio, 3.021; 95% confidence interval, 1.337-6.823; P = 0.008) were independently associated with increased risk of all-cause mortality, whereas technical success had significantly opposing correlation with mortality. (hazard ratio, 0.400, 95% confidence interval, 0.194-0.826, P = 0.013). CONCLUSIONS: Sarcopenia can be highly prevalent in patients with CLTI who undergo endovascular revascularization, and is independently associated with long-term mortality. These results may help risk stratification to assist in personalized assessment and clinical decision-making.

Contemporary outcomes of concomitant suprainguinal bypass with infrainguinal revascularization procedures in patients with chronic limb-threatening ischemia.

OBJECTIVE: Combined suprainguinal and infrainguinal revascularization is sometimes necessary in the treatment of patients with chronic limb-threatening ischemia (CLTI). However, data on outcomes of concomitant revascularization procedures are lacking. We studied the outcomes of patients with CLTI who underwent suprainguinal bypass (SIB) alone, SIB with concomitant infrainguinal bypass (IIB), and SIB with concomitant infrainguinal peripheral endovascular intervention (IIPVI). METHODS: We reviewed all patients in the Vascular Quality Initiative with CLTI who underwent SIB from January 2010 to June 2020. Logistic regression, Kaplan-Meier survival estimates, log-rank tests, and Cox regression were used to analyze outcomes. Outcomes were 30-day mortality, perioperative myocardial infarction, perioperative major amputation, 1-year amputation-free survival, and 5-year survival. RESULTS: Of 8037 patients included, 81.3% (n = 6537) underwent SIB alone, 9.7% (n = 783) underwent SIB+IIB, and 8.9% (n = 717) underwent SIB+IIPVI. The indication for surgery was rest pain in 5040 (62.5%) and tissue loss in 3031 (37.6%). There were no significant differences in 30-day mortality and perioperative myocardial infarction rates. However, there was 2.8-fold increased odds of perioperative major amputation in both SIB+IIPVI (odds ratio [OR], 2.76; 95% confidence interval [CI], 1.30-5.88; P = .008) and SIB+IIB (OR, 2.79; 95% CI, 1.38-5.54; P = .004) among patients with rest pain as compared with SIB alone. Comparing SIB+IIPVI with SIB alone, there were no significant differences in 1-year freedom from amputation and amputation-free survival. SIB+IIPVI was associated with a 27% increased risk of 5-year mortality (hazard ratio [HR], 1.27; 95% CI, 1.03-1.55; P = .035). Compared with SIB alone, SIB+IIB was associated with 97% increased risk of 1-year major amputation among patients with rest pain (HR, 1.97; 95% CI, 1.06-3.69; P = .033), but a 47% decreased risk of 1-year major amputation or death for patients with tissue loss (HR, 0.53; 95% CI, 0.37-0.78; P = .001). SIB+IIPVI, compared with SIB+IIB, was associated with a two-fold increased risk of 1-year major amputation or death (HR, 2.04; 95% CI, 1.04-2.23), P = .003) and a 52% increased risk of 5-year mortality (HR,1.52; 95% CI, 1.04-2.24; P = .032) among patients with tissue loss. CONCLUSIONS: This study shows that SIB with concomitant infrainguinal revascularization in patients with rest pain is associated with an increased risk of amputation, whereas SIB+IIB in patients with tissue loss is associated with decreased risk of amputation or death. SIB+IIB outperformed SIB+IIPVI in patients with tissue loss. SIB with infrainguinal revascularization should be limited in patients with rest pain in line with current guidelines, but SIB+IIB may be preferred in patients with tissue loss.

A single center's 15-year experience with palliative limb care for chronic limb threatening ischemia in frail patients.

OBJECTIVE: Our institution's multidisciplinary Prevention of Amputation in Veterans Everywhere (PAVE) program allocates veterans with critical limb threatening ischemia (CLTI) to immediate revascularization, conservative care, primary amputation, or palliative limb care according to previously reported criteria. These four groups align with the approaches outlined by the global guidelines for the management of CLTI. In the present study, we have delineated the natural history of the palliative limb care group of patients and quantified the procedural risks and outcomes. METHODS: Veterans prospectively enrolled into the palliative limb cohort of our PAVE program from January 2005 to January 2020 were analyzed. The primary outcome was mortality. The secondary outcomes included overall and limb-related readmissions, limb loss, and wound healing. The clinical frailty scale (CFS) score was calculated, and the 5-year expected mortality was estimated using the Veterans Affairs Quality Enhancement Research Initiative tool. Regression analysis was performed to establish associations among the following variables: mortality, wound, ischemia, and foot infection (WIfI) score, CFS score, overall admissions, and limb-related admissions. RESULTS: The PAVE program enrolled 1158 limbs during 15 years. Of the 1158 limbs, 157 (13.5%) in 145 patients were allocated to the palliative limb care group. The overall mortality of the group was 88.2% (median interval, 3.5 months; range, 0-91 months). Of the 128 patients who had died, 64 (50%) had died within 3 months of enrollment. The predicted 5-year mortality for the group was 66%. The average CFS score for the group was 6.2, denoting persons moderately to severely frail. Using the CFS score, 106 patients were considered frail and 39 were considered not frail. No differences were found in mortality between the frail and nonfrail patients. However, a statistically significant difference was found in early (<3 months) mortality (56.2% vs 37.5%; P = .032). The 30-day limb-related readmission rate was 4.7%. Eventual major amputation was necessary for 18 limbs (11.5%). Wound healing occurred in 30 patients (20.6%). Regression analysis demonstrated no association between the CFS score and mortality (r = 0.55; P = .159) or between the WIfI score and mortality (r = 0.0165; P = .98). However, a significant association was found between the WIfI score and limb-related admissions (r = 0.97; P < .001). CONCLUSIONS: Frail patients with CLTI had high early mortality and a low risk of limb-related complications. They also had a low incidence of deferred primary amputation or limb-related readmissions. In our cohort, the vast majority of patients had died within a few months of enrollment without requiring an amputation. A comprehensive approach to the treatment of CLTI patients should include a palliative limb care option because a significant proportion of these patients will have limited survival and can potentially avoid unnecessary surgery and major amputation.

The influence of socioeconomic status on outcomes of lower extremity arterial reconstruction.

OBJECTIVE: Although it has been shown that patient socioeconomic status (SES) is associated with the surgical treatments chosen for severe peripheral arterial disease (PAD), the association between SES and outcomes of arterial reconstruction have not been well-studied. The objective of this study was to determine if SES is associated with outcomes following lower extremity arterial reconstruction. METHODS: Patients 40 years and older who had surgical revascularization for severe lower extremity PAD were identified in the Nationwide Readmissions Database, 2010 to 2014. Measures of SES including median household income (MHI) quartiles of patients' residential ZIP codes were extracted. Factors associated with repeat revascularization, subsequent major amputations, hospital mortality, and 30-day all-cause readmission were evaluated using multivariable regression analyses. RESULTS: Of the 131,529 patients identified, the majority (61%) were male, and the average age was 69 years. On unadjusted analyses, subsequent amputations were higher among patients in the lowest MHI quartile compared with patients in the highest MHI quartile (13% vs 10%; overall P < .001). On multivariable analyses, compared with patients in the lowest quartile, those in the highest quartile had lower amputation (adjusted odds ratio [aOR], 0.70; 95% confidence interval (CI), 0.63-0.77; overall P < .001) and readmission (aOR, 0.91; 95% CI, 0.84-0.99; overall P = .028) rates. However, subsequent revascularization (aOR, 1.04; 95% CI, 0.94-1.15) and mortality (aOR, 1.01; 95% CI, 0.79-1.28) rates were not different across the groups. CONCLUSIONS: Lower SES is associated with disproportionally worse outcomes following lower extremity arterial reconstruction for severe PAD. These data suggest that improving outcomes of lower extremity arterial reconstruction may involve addressing socioeconomic disparities.

Long-Term Mortality Predictors Using a Machine-Learning Approach in Patients With Chronic Limb-Threatening Ischemia After Peripheral Vascular Intervention.

BACKGROUND: Patients with chronic limb-threatening ischemia (CLTI) face a high long-term mortality risk. Identifying novel mortality predictors and risk profiles would enable individual health care plan design and improved survival. We aimed to leverage a random survival forest machine-learning algorithm to identify long-term all-cause mortality predictors in patients with CLTI undergoing peripheral vascular intervention. METHODS AND RESULTS: Patients with CLTI undergoing peripheral vascular intervention from 2017 to 2018 were derived from the Medicare-linked VQI (Vascular Quality Initiative) registry. We constructed a random survival forest to rank 66 preprocedural variables according to their relative importance and mean minimal depth for 3-year all-cause mortality. A random survival forest of 2000 trees was built using a training sample (80% of the cohort). Accuracy was assessed in a testing sample (20%) using continuous ranked probability score, Harrell C-index, and out-of-bag error rate. A total of 10 114 patients were included (mean±SD age, 72.0±11.0 years; 59% men). The 3-year mortality rate was 39.1%, with a median survival of 1.4 years (interquartile range, 0.7-2.0 years). The most predictive variables were chronic kidney disease, age, congestive heart failure, dementia, arrhythmias, requiring assisted care, living at home, and body mass index. A total of 41 variables spanning all domains of the biopsychosocial model were ranked as mortality predictors. The accuracy of the model was excellent (continuous ranked probability score, 0.172; Harrell C-index, 0.70; out-of-bag error rate, 29.7%). CONCLUSIONS: Our random survival forest accurately predicts long-term CLTI mortality, which is driven by demographic, functional, behavioral, and medical comorbidities. Broadening frameworks of risk and refining health care plans to include multidimensional risk factors could improve individualized care for CLTI.

Emerging trends in nationwide mortality, limb loss, and resource utilization for critical limb ischemia in young adults.

BACKGROUND/OBJECTIVES: Recent trends indicate a rise in the incidence of critical limb ischemia (CLI) among younger adults. This study examines trends in CLI hospitalization and outcomes among young adults with peripheral arterial disease (PAD) in the United States. METHODS: Adult hospitalizations (18-40 years) for PAD/CLI were analyzed from the 2016-2020 nationwide inpatient sample database using ICD-10 codes. Rates were reported per 1000 PAD or 100,000 cardiovascular disease admissions. Outcomes included trends in mortality, major amputations, revascularization, length of hospital stay (LOS), and hospital costs (THC). We used the Jonckheere-Terpstra tests for trend analysis and adjusted costs to the 2020 dollar using the consumer price index. RESULTS: Approximately 63,045 PAD and 20,455 CLI admissions were analyzed. The mean age of the CLI cohort was 32.7 ± 3 years. The majority (12,907; 63.1 %) were female and white (11,843; 57.9 %). Annual CLI rates showed an uptrend with 3265 hospitalizations (227 per 1000 PAD hospitalizations, 22.7 %) in 2016 to 4474 (252 per 1000 PAD hospitalizations, 25.2 %) in 2020 (Ptrend<0.001), along with an increase in PAD admissions from 14,405 (188 per 100,000, 0.19 %) in 2016 to 17,745 (232 per 100,000, 0.23 %%) in 2020 (Ptrend<0.0001). Annual in-hospital mortality increased from 570 (2.8 %) in 2016 to 803 (3.9 %) in 2020 (Ptrend = 0.001) while amputations increased from 1084 (33.2 %) in 2016 to 1995 (44.6 %) in 2020 (Ptrend<0.001). Mean LOS increased from 5.1 (SD 2.7) days in 2016 to 6.5 (SD 0.9) days in 2020 (Ptrend = 0.002). The mean THC for CLI increased from $50,873 to $69,262 in 2020 (Ptrend<0.001). The endovascular revascularization rates decreased from 11.5 % (525 cases) in 2016 to 10.7 % (635 cases) in 2020 (Ptrend = 0.025). Surgical revascularization rates also increased from 4.9 % (225 cases) in 2016 to 10.4 % (600 cases) in 2020 (Ptrend = 0.041). CONCLUSION: Hospitalization and outcomes for CLI worsened among young adults during the study period. There is an urgent need to enhance surveillance for risk factors of PAD in this age group.