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.

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).

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.

Development of a biomarker panel for assessing cardiovascular risk in diabetic patients with chronic limb-threatening ischemia (CLTI): a prospective study.

BACKGROUND: Lower-extremity endovascular revascularization (LER) is often required for diabetic patients with chronic limb threatening ischemia (CLTI). During the post-revascularization period patients may unpredictably experience major adverse cardiac events (MACE) and major adverse limb events (MALE). Several families of cytokines are involved in the inflammatory process that underlies the progression of atherosclerosis. According to current evidence, we have identified a panel of possible biomarkers related with the risk of developing MACE and MALE after LER. The aim was to study the relationship between a panel of biomarkers - Interleukin-1 (IL-1) and 6 (IL-6), C-Reactive Protein (CRP), Tumor Necrosis Factor-α (TNF-α), High-Mobility Group Box-1 (HMGB-1), Osteoprotegerin (OPG), Sortilin and Omentin-1- at baseline, with cardiovascular outcomes (MACE and MALE) after LER in diabetic patients with CLTI. METHODS: In this prospective non-randomized study, 264 diabetic patients with CLTI undergoing endovascular revascularization were enrolled. Serum levels of each biomarker were collected before revascularization and outcomes' incidence was evaluated after 1, 3, 6 and 12 months. RESULTS: During the follow-up period, 42 cases of MACE and 81 cases of MALE occurred. There was a linear association for each biomarker at baseline and incident MACE and MALE, except Omentin-1 levels that were inversely related to the presence of MACE or MALE. After adjusting for traditional cardiovascular risk factors, the association between each biomarker baseline level and outcomes remained significant in multivariable analysis. Receiver operating characteristics (ROC) models were constructed using traditional clinical and laboratory risk factors and the inclusion of biomarkers significantly improved the prediction of incident events. CONCLUSIONS: Elevated IL-1, IL-6, CRP, TNF-α, HMGB-1, OPG and Sortilin levels and low Omentin-1 levels at baseline correlate with worse vascular outcomes in diabetic patients with CLTI undergoing LER. Assessment of the inflammatory state with this panel of biomarkers may support physicians to identify a subset of patients more susceptible to the procedure failure and to develop cardiovascular adverse events after LER.

Outcomes of a bypass-first strategy in chronic limb-threatening ischemia based on the Global Vascular Guidelines.

OBJECTIVE: The Global Vascular Guidelines (GVGs) recommend initial revascularization (bypass or endovascular therapy) for chronic limb-threatening ischemia (CLTI) based on anatomical complexity and limb severity. This decision is made based on a prediction of the outcomes after endovascular intervention. This study was performed to evaluate outcomes after distal bypass in cases recommended for GVG bypass. METHODS: A total of 239 distal bypasses for CLTI were evaluated in 195 patients with a GVG bypass recommendation treated between 2009 and 2020 at a single center in Japan. Comparisons were made between crural and pedal bypass cases. RESULTS: The 195 patients (median age, 77 years; 67% male) underwent 133 crural bypasses (106 patients; 54%) and 106 pedal bypasses (89 patients; 46%). Hemodialysis was more common in pedal cases than in crural cases (P = .03). Hospital deaths occurred in two cases (1%) within 30 days. The whole cohort has a follow-up rate of 96% over a mean of 28 ± 26 months, with 3-year limb salvage rates of 87% and 3-year primary, assisted primary, and secondary patency rates of 40%, 65%, and 67%, all without significant differences between crural and pedal cases. The 1-year wound healing rate was 88% and tended to be higher in crural cases than in pedal cases (P = .068). The 3-year survival rate was 52% in the cohort and did not differ significantly between crural and pedal cases. CONCLUSIONS: Patients with CLTI with a GVG bypass recommendation had acceptable limb salvage, graft patency, wound healing, and survival after distal bypass, regardless of the bypass method. These findings indicate that a GVG bypass recommendation as an initial revascularization method is valid in the real world.

Treatment outcomes between bypass surgery and endovascular therapy in patients with chronic limb-threatening ischemia classified as bypass-preferred category based on Global Vascular Guidelines.

OBJECTIVE: The aim of this study was to examine outcomes between bypass surgery and endovascular therapy (EVT) in patients with chronic limb-threatening ischemia (CLTI), classified as bypass-preferred according to the Global Vascular Guidelines (GVG). METHODS: We retrospectively analyzed the multi-center data of patients who underwent infrainguinal revascularization for CLTI with Wound, Ischemia, and foot Infection (WIfI) Stage 3 to 4 and Global Limb Anatomical Staging System (GLASS) Stage III, which is classified as bypass-preferred category by the GVG between 2015 and 2020. The endpoints were limb salvage and wound healing. RESULTS: We analyzed 301 patients and 339 limbs following 156 bypass surgeries and 183 EVTs. The 2-year limb salvage rates were 92.2% in the bypass surgery group and 76.3% in the EVT group, respectively (P < .01). The 1-year wound healing rates were 86.7% in the bypass surgery group and 67.8% in the EVT group (P < .01). Multivariate analysis shows decreased serum albumin level (P < .01), increased wound grade (P = .04), and EVT (P < .01) were risk factors for major amputation. Decreased serum albumin level (P < .01), increased wound grade (P < .01), GLASS infrapopliteal grade (P = .02), inframalleolar (IM) P grade (P = .01), and EVT (P < .01) were risk factors for impaired wound healing. Subgroup analysis of limb salvage in patients after EVT, decreased serum albumin level (P < .01), increased wound grade (P = .03), increased IM P grade (P = .04), and congestive heart failure (P < .01) were risk factors for major amputation. According to scoring by existence of these risk factors, 2-year limb salvage rates following EVT were 83.0% and 42.8% for the total score of 0 to 2 and of 3 to 4, respectively (P < .01). CONCLUSIONS: Bypass surgery provides better limb salvage and wound healing in patients with WIfI Stage 3 to 4 and GLASS Stage III, which is classified as bypass-preferred category by the GVG. In patients after EVT, serum albumin level, wound grade, IM P grade, and congestive heart failure were related to major amputation. Although bypass surgery may be considered as initial revascularization procedure in patients classified as bypass-preferred category, in case that EVT has to be selected, relatively acceptable outcomes can be expected in patients with less of these risk factors.

Impact of ambulatory status change on survival in patients with chronic limb-threatening ischemia undergoing infrainguinal surgical or endovascular revascularization.

OBJECTIVE: This study aimed to evaluate the influence of change in ambulatory status on the prognosis of patients with chronic limb-threatening ischemia (CLTI) undergoing infrainguinal bypass surgery or endovascular therapy (EVT). METHODS: We retrospectively analyzed data from two vascular centers for patients who underwent revascularization for CLTI between 2015 and 2020. The primary endpoint was overall survival (OS), and the secondary endpoints were changes in ambulatory status and postoperative complications. RESULTS: Throughout the study, 377 patients and 508 limbs were analyzed. In the preoperative nonambulation cohort, the average body mass index (BMI) was lower in the postoperative nonambulatory group than in the postoperative ambulatory group (P < .01). The percentage of cerebrovascular disease (CVD) was higher in the postoperative nonambulatory group than in the postoperative ambulatory group (P = .01). In the preoperative ambulation cohort, the average controlling nutritional status (CONUT) score was higher in the postoperative nonambulatory group than in the postoperative ambulatory group (P < .01). There was no difference in the bypass percentage and the EVT in the preoperative nonambulation (P = .32) and ambulation (P = .70) cohorts. According to the change in ambulatory status before and after revascularization, the 1-year OS rates were 86.8% in the ambulatory → ambulatory group, 81.1% in the nonambulatory → ambulatory group, 54.7% in the nonambulatory → nonambulatory group, and 23.9% in the ambulatory → nonambulatory group (P < .01). On multivariate analysis, increased age (P = .04), higher Wound, Ischemia, and foot Infection stage (P = .02), and increased CONUT score (P < .01) were independent risk factors for the decline in ambulatory status in patients with preoperative ambulation. In patients with preoperative nonambulation, increased BMI (P < .01) and absence of CVD (P = .04) were independent factors related to the improved ambulatory status. The percentages of postoperative complications were 31.0% and 17.0% in the preoperative nonambulation and the preoperative ambulation in the overall cohort (P < .01). Preoperative nonambulatory status (P < .01), CONUT score (P < .01), and bypass surgery (P < .01) were risk factors for postoperative complications. CONCLUSIONS: Improved ambulatory status is associated with better OS in patients with preoperative nonambulatory status after infrainguinal revascularization for CLTI. Although patients with preoperative nonambulatory status have a risk of postoperative complication, some may benefit from revascularization if they have no factors such as low BMI and CVD, improving their ambulatory status.

Integration of palliative care consultation into the management of patients with chronic limb-threatening ischemia.

OBJECTIVE: We assessed the feasibility of integrating palliative care consultation into the routine management of patients with chronic limb-threatening ischemia (CLTI). Additionally, we sought to describe patient-reported outcomes from the palliative care and vascular literature in patients with CLTI receiving a palliative care consultation at our institution. METHODS: This was a single-institution, prospective, observational study that aimed to assess feasibility of incorporating palliative care consultation into the management of patients admitted to our tertiary academic medical center with CLTI by looking at utilization of palliative care before and after implementation of a protocol-based palliative care referral system. A survey comprised of patient-reported outcomes from the palliative care literature was administered to patients before and after palliative consultation. Length of stay and mortality were compared between our study cohort and a historic cohort of patients admitted with CLTI. RESULTS: Over a 14-month enrollment period, 44% of patients (n = 39) with CLTI (rest pain, 36%; tissue loss, 64%) admitted to the vascular service received palliative care consultation, compared with 5% of patients (n = 4) who would have met criteria over the preceding 14 months before our protocol was instituted. The mean age was 69 years, 23% were female, 92% were white, and 49% were able to ambulate independently. Revascularization included bypass (46%), peripheral vascular intervention (23%), and femoral endarterectomy (21%). Additional procedures included minor amputation or wound debridement (26%) and major amputation (15%). No patients received medical management alone. After receiving palliative care consultation, patients reported experiencing less emotional distress than before consultation (P = .03). They also reported being less bothered by uncertainty regarding what to expect from the course of their illness (P = .002). Fewer patients reported being unsure of the purpose of their medical care after palliative care consultation (8%) vs before (18%), although this was not statistically significant (P = .10). Median length of stay was longer in the study group compared with the historic cohort (8 vs 7 days; P = .02). There was no difference in 30-day mortality (3% vs 8%; P = .42) between the study group and the historic cohort (n = 77). CONCLUSIONS: Integrating inpatient palliative care consultation into the routine management of patients with CLTI is feasible and may improve emotional domains of health-related quality of life. This study laid the foundation for future studies on longer term outcomes of patients with CLTI undergoing palliative care consultation as well as the benefit of outpatient palliative care consultation in patients with CLTI.

Distal Endarterectomy Combined With Endovascular Proximal Treatment: The Hybrid DEEP Retrograde Technique for High-Complexity Infrainguinal Disease.

Purpose: We present a hybrid technique for the treatment of chronic limb-threatening ischemia (CLTI) due to complex, multilevel infrainguinal disease. It consists of an open distal endarterectomy combined with endovascular proximal treatment (the DEEP technique). Materials and Methods: This was a prospective cohort study. Thirty-three limbs (30 patients) were treated. Main inclusion criteria were absence of significant disease in femoral bifurcation associated with a complex infrainguinal pattern. This approach was specially considered in absence of suitable vein for bypass, obesity, hostile groin, and overall high surgical risk. Results: Mean age was 72.8 ± 10 years (ranging 50-93). Most cases presented with severe limb threatening onset (90.9% Rutherford >4 and 81.8% WIfi >3) due to high-complexity infrainguinal disease pattern (Global Limb Anatomic Staging System [GLASS] stage III) in 31/33 (93.9%), chronic total occlusions (CTOs) in 24/33 (72.7%), and severe calcification (Peripheral Arterial Calcium Scoring System [PACSS] grade 4) in 22/33 (66.6%). Mean lesion length was 228.2 mm ± 83 (ranging 40-340 mm). In all procedures, a covered-stent (25 cm length Viabahn) was implanted in a retrograde fashion as the endovascular component. Effective revascularization was achieved in all cases, showing significant clinical and hemodynamic improvement (median pre- and postprocedure ankle-brachial index [ABI]: 0.3 and 0.9, respectively). Results at 12 months follow-up were as follows: 93.9% limb salvage ratio, 75.7% primary patency, 84.6% assisted primary patency, and 90.9% secondary patency. Major adverse limb events (MALE) and cardiovascular events (MACE) occurred in 8/33 (24.2%) and 2/33 (6%), respectively. Mean length of postoperative stay was 7.5 ± 6.92 days (3-27). Conclusion: This less invasive hybrid technique has promising short-term results for limb salvage and it is worth to be included in vascular armamentarium for CLTI revascularization in selected patients.

Differential impact of missed initial wound clinic visit on 6-month wound healing by race/ethnicity among patients with chronic limb-threatening ischemia.

Chronic limb-threatening ischemia (CLTI) is associated with significant morbidity, including major limb amputation, and mortality. Healing ischemic wounds is necessary to optimise vascular outcomes and can be facilitated by dedicated appointments at a wound clinic. This study aimed to estimate the association between successful wound care initiation and 6-month wound healing, with specific attention to differences by race/ethnicity. This retrospective study included 398 patients with CLTI and at least one ischaemic wound who scheduled an appointment at our wound clinic between January 2015 and July 2020. The exposure was the completion status of patients' first scheduled wound care appointment (complete/not complete) and the primary outcome was 6-month wound healing (healed/not healed). The analysis focused on how this association was modified by race/ethnicity. We used Aalen-Johansen estimators to produce cumulative incidence curves and calculated risk ratios within strata of race/ethnicity. The final adjustment set included age, revascularization, and initial wound size. Patients had a mean age of 67 ± 14 years, were 41% female, 46% non-White and had 517 total wounds. In the overall cohort, 70% of patients completed their first visit and 34% of wounds healed within 6-months. There was no significant difference in 6-month healing based on first visit completion status for White/non-Hispanic individuals (RR [95% CI] = 1.18 [0.91, 1.45]; p-value = 0.130), while non-White individuals were roughly 3 times more likely to heal their wounds if they completed their first appointment (RR [95% CI] = 2.89 [2.66, 3.11]; p-value < 0.001). In conclusion, non-White patients were approximately three times more likely to heal their wound in 6 months if they completed their first scheduled wound care appointment while White/non-Hispanic individuals' risk of healing was similar regardless of first visit completion status. Future efforts should focus on providing additional resources to ensure minority groups with wounds have the support they need to access and successfully initiate wound care.

Primary results of the SAVAL randomized trial of a paclitaxel-eluting nitinol stent versus percutaneous transluminal angioplasty in infrapopliteal arteries.

BACKGROUND: Effective and durable options for infrapopliteal artery revascularization for patients with chronic limb-threatening ischemia (CLTI) are limited. METHODS: The SAVAL trial is a prospective, multicenter, randomized trial of patients with CLTI and infrapopliteal artery lesions with total lesion length ⩽ 140 mm, stenosis ⩾ 70%, and Rutherford category 4-5 assigned 2:1 to treatment with the SAVAL self-expandable paclitaxel drug-eluting stent (DES) or percutaneous transluminal angioplasty (PTA) with an uncoated balloon. The primary effectiveness endpoint was primary vessel patency (i.e., core lab-adjudicated duplex ultrasound-based flow at 12 months in the absence of clinically driven target lesion revascularization or surgical bypass of the target lesion). The primary safety endpoint was the 12-month major adverse event (MAE)-free rate; MAEs were defined as a composite of above-ankle index limb amputation, major reintervention, and 30-day mortality. The endpoints were prespecified for superiority (effectiveness) and noninferiority (safety) at a one-sided significance level of 2.5%. RESULTS: A total of 201 patients were enrolled and randomly assigned to treatment (N = 130 DES, N = 71 PTA). Target lesion length was 68.1 ± 35.2 mm for the DES group and 68.7 ± 49.2 mm for the PTA group, and 31.0% and 27.6% of patients, respectively, had occlusions. The 12-month primary patency rates were 68.0% for the DES group and 76.0% for the PTA group (Psuperiority = 0.8552). The MAE-free rates were 91.6% and 95.3%, respectively (Pnoninferiority = 0.0433). CONCLUSION: The SAVAL trial did not show benefit related to effectiveness and safety with the nitinol DES compared with PTA in infrapopliteal artery lesions up to 140 mm in length. Continued innovation to provide optimal treatments for CLTI is needed. (ClinicalTrials.gov Identifier: NCT03551496).

Lower-extremity pressure, staging, and grading thresholds to identify chronic limb-threatening ischemia.

INTRODUCTION: The Society for Vascular Surgery Threatened Limb Classification System ('WIfI') is used to predict risk of limb loss and identify peripheral artery disease in patients with foot ulcers or gangrene. We estimated the diagnostic sensitivity of multiple clinical and noninvasive arterial parameters to identify chronic limb-threatening ischemia (CLTI). METHODS: We performed a single-center review of 100 consecutive patients who underwent angiography for foot gangrene or ulcers. WIfI stages and grades were determined for each patient. Toe, ankle, and brachial pressure measurements were performed by registered vascular technologists. CLTI severity was characterized using Global Limb Anatomic Staging System (GLASS stages) and angiosomes. Medial artery calcification in the foot was quantified on foot radiographs. RESULTS: GLASS NA (not applicable), I, II, and III angiographic findings were seen in 21, 21, 23, and 35 patients, respectively. A toe-brachial index < 0.7 and minimum ipsilateral ankle-brachial index < 0.9 performed well in identifying GLASS II and III angiographic findings, with sensitivity rates 97.8% and 91.5%, respectively. The diagnostic accuracy rates of noninvasive measures peaked at 74.7% and 89.3% for identifying GLASS II/III and GLASS I+ angiographic findings, respectively. The presence of medial artery calcification significantly diminished the sensitivity of most noninvasive parameters. CONCLUSIONS: The use of alternative noninvasive arterial testing parameters improves sensitivity for detecting PAD. Abnormal noninvasive results should suggest the need for diagnostic angiography to further characterize arterial anatomy of the affected limb. Testing strategies with better accuracy are needed.

Immunologic profiles in patients with chronic limb-threatening ischemia undergoing endovascular revascularization.

BACKGROUND: Inflammation and immune dysregulation have been associated with adverse outcomes in cardiovascular disease. There is limited understanding of the association of different profiles of white blood cell (WBC) subsets and red cell distribution width (RDW) in patients with chronic limb-threatening ischemia (CLTI). METHODS: Patients with CLTI undergoing endovascular revascularization in our single-center, tertiary care hospital from 2017 to 2019, who had a preceding complete blood count (CBC) with WBC differentials (n =213), were included in the analysis. Patient characteristics, laboratory values, and clinical outcomes were collected. Cox proportional hazards regression models were used to assess for associations between all-cause mortality and leukocyte subset; multivariate analysis was used to account for confounders. Kaplan-Meier curves were generated to depict survival censored at 1 year postrevascularization using baseline CBC indices. RESULTS: Adjusting for confounders, elevated RDW was associated with increased mortality (continuous per % increase, adjusted hazard ratio [HR] 1.33, p < 0.001). Baseline lymphopenia was associated with mortality in univariate analysis. Other leukocyte subtypes were not associated with mortality outcomes in our population. Exploratory analysis showed negative deflections in ∆WBC from pre- to postprocedure day 1 were affiliated with increased mortality when adjusted for age, sex, race, chronic kidney disease, and baseline hemoglobin (∆WBC HR 1.16, p = 0.004). Further exploratory analysis showed an association between RDW and all-comers readmission. CONCLUSIONS: The utilization of a periprocedural WBC subset differential can be a useful adjunct to risk-stratify patients with CLTI undergoing endovascular revascularization. Further studies are needed to understand potential ways to modulate immune dysregulation so as to improve mortality outcomes.

Accuracy of the pedal acceleration time to diagnose limb ischemia in patients with and without diabetes using the WIfI classification.

INTRODUCTION: Evaluation of limb hemodynamics using the ankle-brachial index (ABI) may be difficult due to skin lesions, extensive necrosis, and obesity, such as commonly present in patients with diabetes with chronic limb-threatening ischemia (CLTI). We hypothesized that the pedal acceleration time (PAT) correlates with ABI and Wound, Ischemia, and foot Infection (WIfI) scores in patients with diabetes to serve as a new modality to accurately stage CLTI. METHODS: A single-center, cross-sectional study included patients with and without diabetes > 18 years with CLTI. Limbs were categorized in three grades of ischemia based on the ABI (ABI < 0.8, < 0.6, and < 0.4) and in two classes based on WIfI stages of amputation risk. Receiver operator characteristic (ROC) curves were used to determine PAT sensitivity, specificity, and accuracy to predict lower-limb ischemia. RESULTS: A total of 141 patients (67 nondiabetic and 74 diabetic) and 198 lower limbs (94 nondiabetic and 104 diabetic) met the inclusion criteria. In patients without diabetes, the accuracy of PAT for detecting an ABI < 0.8 was 85%; for detecting an ABI < 0.6 was 85%; and for detecting an ABI < 0.4 was 87%. In patients with diabetes, the accuracy of PAT in detecting an ABI < 0.8 was 91%; for detecting an ABI < 0.6 was 79%; and for detecting an ABI < 0.4 was 88%. In patients without diabetes, the accuracy for detecting WIfI stages of moderate and high amputation risk was 77% and for patients with diabetes was also 77%. CONCLUSIONS: PAT shows high correlation with the ABI as well as with the WIfI stages of amputation risk and the grades of ischemia, with high accuracy.

Contemporary treatment of below-the-knee peripheral arterial disease in patients with chronic limb threatening ischemia: Observations from the Vascular Quality Initiative.

OBJECTIVE: We sought to determine trends in percutaneous transluminal angioplasty (PTA) versus non-PTA interventions over time, as well as factors that influence the decision for non-PTA intervention. BACKGROUND: Although the optimal strategy for revascularization in patients with below-the-knee (BTK) chronic limb-threatening ischemia (CLTI) remains under investigation, PTA has been the preferred endovascular approach. Recently, there has been an increase in the use of non-PTA approaches for revascularization. METHODS: We performed a retrospective analysis of the Vascular Quality Initiative. Between 2011 and 2020, a total of 23,850 procedures corresponding to 33,098 arteries in 19,404 patients with CLTI were included. After application of exclusion criteria and removal of missing variables, 18,644 arteries were included in the study cohort. The primary analysis was factors associated with receiving non-PTA intervention. Secondary analysis included trends in PTA versus non-PTA intervention over time. RESULTS: Throughout the study period, the majority of interventions (72%) were PTA alone. The percentage of non-PTA interventions, on a per-artery basis, increased over the study period from 18% to 33%, p < 0.01. Advanced age, increasing TransAtlantic Inter-Society Consensus classification, and concomitant above-the-knee disease were associated with an increased likelihood for non-PTA intervention. In contrast, longer lesion length, insulin-dependent diabetes mellitus, bilateral disease, and discharge to location other than home were associated with an increased likelihood of PTA. CONCLUSIONS: We observed a significant increase in the percentage of non-PTA interventions for patients with CLTI requiring BTK interventions over the last decade, with lesion- and patient-specific characteristics associated with the type of endovascular approach.

The utility of geriatric nutritional risk index to predict outcomes in chronic limb-threatening ischemia.

OBJECTIVES: To assess geriatric nutritional risk index (GNRI) in patients with chronic limb-threatening ischemia (CLTI). BACKGROUND: The prevalence of CLTI continues to rise, with major amputation and mortality remaining prominent. Frailty is a vital risk factor for adverse outcomes in cardiovascular care. The GNRI is a nutrition-based surrogate for frailty that has been utilized in Southeast Asia to predict adverse events in CLTI. It has not yet been evaluated in a primarily Western population, nor in the context of wound healing. METHODS: Between 8August 2017 and April 2019, we identified patients undergoing endovascular interventions for CLTI at our institution, categorized into low GNRI (≤ 94, frail) versus normal GNRI (> 94, reference). We analyzed the risks of major adverse limb events (MALE), its individual components [mortality, major amputation, and target vessel revascularization (TVR)], amputation free survival (AFS), and wound healing using Kaplan-Meier and multivariate cox-proportional hazard regression analyses. RESULTS: A total of 255 patients were included in the analysis, with follow up of 14 ± 9.1 months. Lower GNRI was associated with higher cumulative event rates for MALE (71.0% vs. 43.3%, p < 0.001), mortality (34.3% vs. 15.2%, p < 0.001), major amputation (31.2% vs. 15.8%, p = 0.002), and freedom from AFS (56.0% vs. 28.2%, p < 0.001). There was a trend toward lower TVR and higher wound healing with higher GNRI score. CONCLUSIONS: Our single-center, retrospective evaluation of GNRI (as a surrogate for frailty) correlated with increased risks of MALE, mortality, and major amputation. Future directions should focus not only on the recognition of these patients, but risk-factor modification to optimize long-term outcomes.