Major Adverse Limb Events Research Articles

Influence of a Novel Morphology-Driven Classification on Limb Salvage after Isolated Tibial Intervention for Chronic Limb Threatening Ischemia

Infra-popliteal interventions for chronic limb-threatening ischemia (CLTI) can be impacted by the morphology of the tibial vessels. The aim of this study was to examine the impact of a novel morphology-driven classification on the outcomes of isolated tibial intervention for CLTI. A database of patients undergoing isolated tibial interventions for CLTI at a single center between 2010 and 2020 was retrospectively queried. Patients with isolated infra-popliteal disease were identified, and their anatomy was scored as present or absent for lesion calcification (1 point), target vessel diameter<3.0mm (1 point), lesion length>300mm (1 point), and poor pedal runoff score (1 point). Patients were then divided into 3 groups: low risk (0 or 1 points), moderate risk (2 points), and high risk (3 or 4 points). Intention to treat analysis by the patient was performed. Limb-based patency (the absence of reintervention, occlusion, critical stenosis [>70%], or hemodynamic compromise with ongoing symptoms of CLTI as it related to the patency of the preoperatively determined target artery pathway) was assessed. Patient-oriented outcomes of amputation-free survival (AFS; survival without major amputation) and freedom from major adverse limb events (MALE; above ankle amputation of the index limb or major reintervention: new bypass graft, jump/interposition graft revision) were evaluated. 1,607 patients (55% male, average age 60years, 3,846 vessels) underwent tibial intervention for CLTI. The majority of the patients were diabetic and of Hispanic origin. Morphologically, 27%, 31%, and 42% of the vessels were categorized as low risk, moderate risk, and high risk, respectively. There was a significant worsening of the infra-popliteal Global Limb Anatomic Staging System (GLASS) grading as the morphological risk increased. The 30-day major adverse cardiac events (MACE) were equivalent across the groups and were under the stated objective performance goal (OPG) of ≤10%. In contrast, both the 30-day MALE and the 30-day major amputations were significantly different across the groups, with the low-risk group remaining under the OPG of ≤9% and ≤4%, respectively, while the moderate risk and high risk exceeded the goal threshold. For the OPG, freedom from MALE was 60±5%, 46±5%, and 22±9% at 5years for low-, moderate-, and high-risk groups, respectively (mean±standard error of the mean; P=0.008). Overall AFS was 55±5%, 37±6%, and 18±7% at 5years for low-, moderate-, and high-risk groups, respectively (mean±standard error of the mean; P=0.003). Tibial anatomic morphology impacts isolated tibial endovascular intervention with adverse morphology associated with poorer short- and long-term outcomes. Risk stratification based on anatomic predictors should be an additional consideration as one intervenes on infra-popliteal vessels for CLTI.

Peripheral artery disease patients with chronic kidney disease have lower muscle strength and mitochondrial function compared to those with normal kidney function

Introduction: Chronic kidney disease is a significant risk factor for both the development of peripheral artery disease (PAD) and major adverse limb events. However, little is known about how the coalescence of these two conditions impacts limb muscle pathophysiology. The objective of the current study was to determine the impact of CKD on skeletal muscle strength and mitochondrial health in patients with and without PAD. Methods: A cross-sectional prospective study design was employed to assess plantar flexor muscle strength, muscle fiber cross-sectional area (CSA), and mitochondrial health in four groups of patients (61 males and 29 females): PAD only (Toe brachial index, TBI&lt;0.5 and eGFR&gt;60 mL/min), CKD only (TBI&gt;0.75 and eGFR:15-45 mL/min), PAD with CKD (TBI&lt;0.5 and eGFR:15-45 mL/min), and adult controls without PAD and CKD (TBI&gt;0.75 and eGFR&gt;60 mL/min). Results: Plantar flexor muscle strength was lowest in PAD patients with CKD compared to adult controls ( P&lt;0.0001), PAD only ( P=0.001), and CKD only ( P=0.003). No differences in the mean muscle fiber CSA were detected. The percentage of COX+ fibers was significantly lower in PAD patients with CKD compared to adult controls ( P=0.03). High resolution respirometry analysis of mitochondrial oxidative phosphorylation (OXPHOS) function demonstrated that CKD has a significant negative impact on muscle bioenergetics. PAD patients with CKD had lower OXPHOS function than adult controls ( P=0.0016) and PAD patients without CKD ( P=0.0015). Notably, CKD patients without PAD also had lower OXPHOS function than adult controls ( P=0.0054) and PAD patients without CKD ( P=0.005). Conclusion: The current results demonstrate a profound negative impact of CKD on the associated myopathy of PAD patients. This study was supported by National Institutes of Health (NIH) grant R01-HL149704 (T.E.R.). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Endovascular Management of Chronic Limb-Threatening Ischemia (CLTI) in the Elderly: A Focus on Frailty, Wound Healing, and Outcomes

In India, a significant scarcity of published data exists regarding chronic limb-threatening ischemia (CLTI) and its management, especially among the elderly population. CLTI, often accompanied by frailty poses a significant healthcare challenge. While endovascular interventions offer hope, there remains a dearth of outcome data for this age group. This study seeks to address this critical gap by investigating the impact of frailty on outcomes, emphasizing amputation-free survival (AFS), wound healing, and health-related quality of life (HRQoL). Our study included 131 elderly CLTI patients aged ≥70 years who underwent infrainguinal endovascular interventions between April 2018 and August 2021, with a follow-up period of 2 years. Among the patients, 93.9% had diabetes mellitus and 82.4% had hypertension. Clinical frailty was assessed using the Clinical Frailty Scale (CFS). Patients were categorized into Group 1 (CFS 1-5) and Group 2 (CFS 6-9). Primary outcomes were AFS, wound healing, HRQoL, and their association with frailty. Secondary outcomes included technical success, procedure-related complications, major adverse limb events (MALE), major adverse cardiovascular events (MACE), vessel patency, re-intervention rates, and mortality rates including peri-procedural and overall mortality. Technical success was achieved in 86.3% of patients, with frailty significantly influencing this outcome. Group 2 exhibited reduced technical success (80.8%) compared to Group 1 (93.1%). The major amputation rate was 9.2%, with higher rates in Group 2 [univariate Hazard Ratio (HR): 5.20; p=0.033]. Similarly, Group 2 showed elevated overall mortality [univariate HR: 5.18; p < 0.001]. AFS at 1 and 2 years were 67.9% and 55% respectively, with higher rates in Group 1. Wound healing was achieved in 76.1% of patients (83/109), with frailty significantly associated with delayed wound healing (p < 0.001). Vessel patency at 1 year was observed in 88.8% of patients. HRQoL significantly improved post-intervention, with VascuQol-6 scores increasing from an average of 9 of 24 at baseline to 20 of 24 at 2 years. Frailty score significantly correlated with VascuQol-6 scores at 1 and 2 years (p < 0.0012). Group 1 exhibited higher VascuQol-6 scores compared to Group 2, indicating improved HRQoL during follow-up. Successful endovascular treatments in high-risk CLTI patients promote improved wound healing and post-treatment quality of life (QoL). Frailty should be assessed before endovascular interventions as it correlates with adverse outcomes, including amputations and mortality. While revascularization holds promise, caution is advised for frailer patients, emphasizing the importance of personalized care and tailored treatments for elderly CLTI patients.

Sex Differences in Mortality Risk after the First Hospitalisation with Lower Extremity Peripheral Arterial Disease

Lower extremity peripheral arterial disease (PAD) is a severe condition that increases the risk of major adverse cardiovascular events, major adverse limb events, and all cause mortality. This study aimed to investigate the mortality risk among females and males hospitalised for the first time with lower extremity PAD. Three cohorts of patients who were admitted for the first time with lower extremity PAD in 2007 - 2010, 2011 - 2014, and 2015 - 2018 were constructed. For the 2007 - 2010 and 2011 - 2014 cohorts, the 28 day, one year, and five year mortality rates were calculated, assessing survival time from date of hospital admission until date of death, end of study period, or censoring. For the 2015 - 2018 cohort, only 28 day and one year mortality were investigated due to lack of follow up data. Mortality rates of these cohorts were compared with the general population using standardised mortality rates (SMRs), and the risk of death between sexes was evaluated using Cox proportional hazards models. Cox models were adjusted for age, cardiovascular disease, and diabetes mellitus to account for potential confounding factors. In total, 7 950, 9 670, and 13 522 patients were included in the 2007 - 2010, 2011 - 2014, and 2015 - 2018 cohorts, respectively. Over 60% of individuals in each cohort were males. Mortality rates at 28 day and one year remained stable across all cohorts, while the five year mortality rate increased for both males and females in the 2011 - 2014 cohort. The SMRs both of females and males with PAD were significantly higher than in the general population. Multivariable regression analyses found no significant differences in mortality risk between sexes at 28 day and one year. However, the five year mortality risk was lower in females, with a hazard ratio of 0.89 (95% confidence interval [CI] 0.83 - 0.97) in the 2007 - 2010 cohort and 0.88 (95% CI 0.82 - 0.94) in the 2011 - 2014 cohort. The five year mortality risk has increased, and females face a lower mortality risk than males. Lower extremity PAD still carries unfavourable long term consequences compared with the general population.

Combined Treatment of Native Femoropopliteal Occlusions in Chronic Limb-Threatening Ischemia Using Atherectomy Debulking and a New Sirolimus Drug-Coated Balloon (SELUTION SLR)

Abstract Objective The aim of this study was to report the primary outcomes of a pilot study investigating the safety and efficacy of sirolimus drug-coated balloons (SELUTION) for endovascular postatherectomy treatment of native occluded femoropopliteal lesions in patients with chronic limb-threatening ischemia (CLTI). Materials and Methods This study analyzes a cohort of CLTI patients with femoropopliteal artery occlusions treated with combined rotational atherectomy and postatherectomy angioplasty using the SELUTION device. The primary outcome measures were amputation-free survival (AFS) defined as time to major limb (above ankle) amputation of the index leg or death from any cause. Secondary outcome measures included technical success, overall survival, major amputation of the index leg, major adverse limb event (MALE) defined as major amputation or any further major revascularization intervention of the treated segment during the follow-up period and primary patency at 12 months. Results Between April 2021 and January 2022, nine patients (mean age: 64.0 ± 8.4, 66.7% male) with femoropopliteal occlusive lesions (mean lesion length: 141.1mm, range: 40–400) were treated with the above-combined approach. Technical success was 100%. At 12 months, the AFS was 88.9%, with one death and zero major amputations (88.9% survival and 100% limb salvage, respectively); only two patients (22.2%) suffered a MALE; primary patency was 75%. No adverse events related to the sirolimus drug-coated balloon nor to the atherectomy device were observed. Conclusion Combining sirolimus drug-coated balloon and atherectomy for treatment of femoropopliteal occlusions in CLTI patients is a safe and effective approach achieving satisfactory patency and adverse event rates.

Evaluation of the efficacy of combined device strategies for long femoropopliteal artery disease.

One of the major problems associated with bare nitinol stent implantation is stent fracture, particularly in the popliteal artery. The purpose of this study was to determine whether drug coated balloons (DCB), interwoven stents (IWS), or plain old balloon angioplasty (POBA) would be suitable for use in distal femoropopliteal (FP) long lesions when an Eluvia stent was implanted proximal to a lesion. This was a multi-center retrospective study enrolling patients undergoing concomitant use of Eluvia with DCB, IWS or POBA for symptomatic atherosclerotic femoropopliteal disease (lesion length > 15cm) [Rutherford category 2-6] between January 2018 and September 2021. 79 patients with 89 femoropopliteal lesions were enrolled in this study. The mean lesion length and the percentage of the popliteal artery involvement was 24.3 ± 6.4cm vs 24.0 ± 9.0cm vs 26.6 ± 6.2cm and 65.8% vs 89.4% vs 67.8% for the Eluvia + DCB, Eluvia + IWS, and Eluvia + POBA groups, respectively. The 1-year Kaplan-Meier estimates of primary patency and freedom from major adverse limb events (MALEs) were 53.3% vs 44.1% vs 24.2% and 62.4% vs 51.0% vs 28.1%, respectively. Eluvia + POBA was associated with a lower rate for 1-year primary patency (HR 2.49; 95% confidence interval (CI): 1.28-4.87; p = 0.007 and HR 2.38; 95% CI: 1.13-5.77; p = 0.04). In SFA long lesions with proximal Eluvia implantation, distal implantations of either a DCB or IWS were comparable, as opposed to POBA alone which generated worse results.

Rationale and design for the randomized placebo-controlled double-blind trial studying the effect of single antiplatelet therapy (clopidogrel) versus dual antiplatelet therapy (clopidogrel/acetylsalicylic acid) on the occurrence of atherothrombotic events following lower extremity peripheral transluminal angioplasty (CLEAR-PATH)

RationaleAntiplatelet therapy (APT) is the standard of care after endovascular revascularization (EVR) in patients with peripheral artery disease (PAD). APT aims to prevent both major adverse cardiovascular events (MACE) and major adverse limb events (MALE). Nonetheless, the rates of MACE and MALE after EVR remain high. In coronary artery and cerebrovascular disease, dual APT (DAPT)compared to acetylsalicylic acid alone has proven to reduce MACE without increasing the risk of major bleeding when applied for a restricted number of weeks. However, within the PAD population, insufficient data are available to understand the potential attributable effect of DAPT over single APT (SAPT). Therefore, prospective randomized studies in targeted study populations are warranted. Trial designCLEAR-PATH is a Dutch multicenter, double-blind, placebo-controlled, randomized trial comparing SAPT (clopidogrel 75mg plus placebo) with DAPT (clopidogrel 75mg plus acetylsalicylic acid 80mg) in patients with PAD undergoing EVR. CLEAR-PATH includes a time-to-event analysis with a follow-up of one year. The primary composite efficacy endpoint consists of all-cause mortality, nonfatal stroke, nonfatal myocardial infarction, severe limb ischemia, (indication for) re-intervention due to any symptomatic restenosis, re-occlusion, or due to acute limb ischemia, and major amputation. The primary safety endpoint contains major bleeding following the Thrombolysis In Myocardial Infarction classification. The enrolment started in August 2022. In total 450 primary efficacy outcome events are required which expectedly amounts to 1696 subjects. Recruitment will take approximately 36 months. ConclusionCLEAR-PATH will assess the efficacy and safety of DAPT compared to SAPT following EVR in PAD patients.

A Systematic Review and Meta-Analysis of Efficacy and Safety of Cilostazol Prescription in Patients With Femoropopliteal Peripheral Artery Disease After Endovascular Therapy.

The purpose of this study is to assess the efficacy and safety of cilostazol prescription in patients with femoropopliteal peripheral artery disease (PAD) after endovascular therapy (EVT). We conducted a systematic review and meta-analysis of all studies reporting the outcomes of cilostazol after femoropopliteal EVT of PAD up to September 2022. Clinical outcomes of interest included primary patency, in-stent restenosis (ISR), vessel re-occlusion, freedom from target lesion revascularization (TLR), repeat revascularization, all-cause mortality, amputation, major adverse cardiovascular events (MACEs) and major adverse limb events (MALEs), and bleeding complication. A total of 4 randomized controlled trials (RCTs) and 8 observational studies containing a total of 4898 patients met the inclusion criteria and were included in this systematic review and meta-analysis. We found that the use of cilostazol was associated with higher primary patency after femoropopliteal artery EVT (odds ratio [OR]=1.67, 95% confidence interval [CI]=1.50-1.87, p<0.001, I2=33.2%), a lower risk of ISR (OR=0.43, 95% CI=0.29-0.63, p<0.001, I2=37.6%), repeat revascularization (OR=0.43, 95% CI=0.24-0.76, p<0.005, I2=27.4%), and vessel re-occlusion (OR=0.59, 95% CI=0.38-0.93, p<0.05, I2=0%). There was an increase in freedom from TLR rate (OR=2.19, 95% CI=1.58-3.05, p<0.001, I2=0%), as well as a reduction in the occurrence of MALEs (OR=0.50, 95% CI=0.29-0.85, p<0.05, I2=0%). However, there was no significant difference in amputation, MACEs, all-cause mortality, and major bleeding complications. Subgroup analysis showed that cilostazol treatment in patients with femoropopliteal drug-eluting stents (DES) implantation remained associated with higher primary patency and a lower risk of ISR. After EVT of femoropopliteal artery lesions, additional oral cilostazol enhances primary patency, reduces the occurrences of ISR and vessel re-occlusion, diminishes the risks associated with MALEs, lowers the need for repeat revascularization, and increases freedom from TLR rates. However, it does not impact amputation, MACEs, all-cause mortality, or major bleeding complications. These findings suggest cilostazol as a potentially safe and effective adjunct therapy in patients with femoropopliteal PAD after EVT. After undergoing endovascular therapy (EVT) for femoropopliteal artery lesions, the addition of cilostazol to antiplatelet therapy can significantly improve primary patency, reducing the incidence of in-stent restenosis, repeat revascularization, vessel re-occlusion, and major adverse limb events while increasing freedom from target lesion revascularization rate. The simultaneous use of drug-eluting stents in the femoropopliteal artery lesions, combined with cilostazol, potentially results in a synergistic anti-stenotic effect. This therapeutic approach does not appear to be associated with an increased risk of major bleeding events or all-cause mortality. These findings provide additional evidence supporting the treatment of anti-stenosis in patients with femoropopliteal artery lesions after EVT.

Development and evaluation of a prediction model for peripheral artery disease-related major adverse limb events using novel biomarker data

ObjectivePrognostic tools for individuals with peripheral artery disease (PAD) remain limited. We developed prediction models for 3-year PAD-related major adverse limb events (MALE) using demographic, clinical, and biomarker data previously validated by our group. MethodsWe performed a prognostic study using a prospectively recruited cohort of patients with PAD (n = 569). Demographic/clinical data were recorded including sex, age, comorbidities, previous procedures, and medications. Plasma concentrations of three biomarkers (N-terminal pro-B-type natriuretic peptide [NT-proBNP], fatty acid binding protein 3 [FABP3], and FABP4) were measured at baseline. The cohort was followed for 3 years. MALE was the primary outcome (composite of open/endovascular vascular intervention or major amputation). We trained three machine learning models with 10-fold cross-validation using demographic, clinical, and biomarker data (random forest, decision trees, and Extreme Gradient Boosting [XGBoost]) to predict 3-year MALE in patients. Area under the receiver operating characteristic curve (AUROC) was the primary model evaluation metric. ResultsThree-year MALE was observed in 162 patients (29%). XGBoost was the top-performing predictive model for 3-year MALE, achieving the following performance metrics: AUROC = 0.88 (95% confidence interval [CI], 0.84-0.94); sensitivity, 88%; specificity, 84%; positive predictive value, 83%; and negative predictive value, 91% on test set data. On an independent validation cohort of patients with PAD, XGBoost attained an AUROC of 0.87 (95% CI, 0.82-0.90). The 10 most important predictors of 3-year MALE consisted of: (1) FABP3; (2) FABP4; (3) age; (4) NT-proBNP; (5) active smoking; (6) diabetes; (7) hypertension; (8) dyslipidemia; (9) coronary artery disease; and (10) sex. ConclusionsWe built robust machine learning algorithms that accurately predict 3-year MALE in patients with PAD using demographic, clinical, and novel biomarker data. Our algorithms can support risk stratification of patients with PAD for additional vascular evaluation and early aggressive medical management, thereby improving outcomes. Further validation of our models for clinical implementation is warranted.

Anticoagulation in Patients with Premature Peripheral Artery Disease Undergoing Lower Extremity Revascularization

ObjectivesPremature peripheral artery disease (PAD), defined by lower extremity revascularization (LER) at age ≤ 50 years, is associated with poor major adverse limb events. The early onset of disease is thought to be influenced by genetic factors that regulate homeostasis of the vascular wall and coagulation. The aim of this study is to investigate the effect of anticoagulation as an adjunct to antiplatelet therapy on the outcomes of LER in patients with premature PAD. MethodsThere were 8,804 patients with premature PAD on pre- and post-operative antiplatelet therapy only and 1,236 patients on pre- and post-operative anticoagulation plus antiplatelet therapy in the Vascular Quality Initiative (VQI) peripheral vascular intervention, infra-, and suprainguinal files. Propensity score matching (2:1) was performed between patients with premature PAD who were on antiplatelet therapy and those on anticoagulation plus antiplatelet therapy. Perioperative and one-year outcomes were analyzed including reintervention, major amputation, and mortality. ResultsPatients on anticoagulation were more likely to have coronary artery disease (48.7% vs 41.2%, P<.001), congestive heart failure (20.2% vs 13.1%, P<.001), and have undergone prior LER (73.9% vs 49.2%, P<.001) compared to patients on antiplatelet therapy only. They were also less likely to be independently ambulatory (74.2% vs 81.8%, P<.001) and be on a statin medication (66.8% vs 74.3%, P<.001) compared to patients on antiplatelet therapy only. Patients on anticoagulation were also less likely to be treated for claudication (38.1% vs 48.6%, P<.001), and less likely to be treated with an endovascular procedure (64.8% vs 73.8%, P<.001). After matching for baseline characteristics, there were 1,256 patients on antiplatelet therapy only and 628 patients on anticoagulation. Patients on anticoagulation were more likely to require a return to the operating room (3.7% vs 1.6%, P<.001) and had higher perioperatively mortality (1.1% vs 0.3%, P=.032), but major amputation was not significantly different (1.8% vs 1.6%, P=.798) compared to patients on antiplatelet therapy alone. At one-year, amputation-free survival was higher in patients on antiplatelets only compared to patients on anticoagulation and antiplatelet medications (87.5% vs 80.9%, log-rank P=.001). ConclusionAnticoagulation in addition to antiplatelet therapy in patients with premature PAD undergoing lower extremity revascularization is associated with increased reintervention and mortality at one year.

“Evolution of Drug-Coated Devices for the Treatment of Chronic Limb Threatening Ischemia”

For patients with Chronic Limb Threatening Ischemia (CLTI), endovascular approaches to revascularization are often employed as a component of multimodality care aimed at limb preservation. However, patients with CLTI are also prone to treatment failure, particularly following balloon angioplasty alone. Drug-coated devices utilizing Paclitaxel were developed to decrease restenosis but have been primarily studied in patients presenting with claudication. In recent years, data have emerged which describe the efficacy of drug-coated devices in the treatment of patients with CLTI. Concurrently, there has been major controversy surrounding the use of drug-coated devices in peripheral arterial disease. A historical narrative of the development and use of drug-coated devices for peripheral arterial disease is presented, along with discussion of major trials. Evidence argues that paclitaxel-based therapies for peripheral arterial disease (PAD) do not increase mortality risk compared to nondrug-coated devices. In CLTI patients, paclitaxel-based balloons and stents provide superior patency and freedom reintervention compared to nondrug-coated devices when treating femoropopliteal disease. However, the use of Paclitaxel-based therapies for below-the-knee (BTK) interventions has not been shown to provide clinically meaningful outcomes compared to nondrug-based therapies. Newer generation antiproliferative agents (Sirolimus, Everolimus) and delivery systems (bioabsorbable scaffolds) hold promise for BTK interventions with early data suggesting decreased rates of major amputation or major adverse limb events.

Medical Optimization of Patients with Symptomatic Peripheral Arterial Disease

Peripheral artery disease (PAD) is a progressive disease associated with the occurrence of major adverse cardiovascular and limb events, and elevated mortality rates. Symptoms of PAD, including claudication and chronic limb threatening ischemia, impair functional capacity and lead to lower quality of life. The focus of current therapies is to minimize symptoms, improve quality of life, and reduce adverse cardiovascular and limb events. Among the medical therapies are antiplatelets, anticoagulants, antihypertensives, cilostazol and pentoxifylline, and novel blood sugar-lowering therapies, plus exercise therapy and smoking cessation. In this review, we discuss these evidence-based medical therapies that are available for patients with symptomatic PAD.

Aortobifemoral bypass vs covered endovascular reconstruction of aortic bifurcation

BackgroundCovered endovascular reconstruction of aortic bifurcation (CERAB) is increasingly used as a first line-treatment in patients with aortoiliac occlusive disease (AIOD). We sought to compare the outcomes of patients who underwent CERAB compared with the gold standard of aortobifemoral bypass (ABF). MethodsThe Vascular Quality Initiative was queried for patients who underwent ABF or CERAB from 2009 to 2021. Propensity scores were generated using demographics, comorbidities, Rutherford class, and urgency. The two groups were matched using 5-to-1 nearest-neighbor match. Our primary outcomes were 1-year estimates of primary patency, major adverse limb events (MALEs), MALE-free survival, reintervention-free survival, and amputation-free survival. Standard statistical methods were used. ResultsA total of 3944 ABF and 281 CERAB cases were identified. Of all patients with AIOD, the proportion of CERAB increased from 0% to 17.9% between 2009 and 2021. Compared with ABF, patients who underwent CERAB were more likely to be older (64.7 vs 60.2; P < .001) and more often had diabetes (40.9% vs 24.1%; P < .001) and end-stage renal disease (1.1% vs 0.3%; P = .03). In the matched analysis (229 CERAB vs 929 ABF), ABF patients had improved MALE-free survival (93.2% [±0.9%] vs 83.2% [±3%]; P < .001) and lower rates of MALE (5.2% [±0.9%] vs 14.1% [±3%]; P < .001), with comparable primary patency rates (98.3% [±0.3%] vs 96.6% [±1%]; P = .6) and amputation-free survival (99.3% [±0.3%] vs 99.4% [±0.6%]; P = .9). Patients in the CERAB group had significantly lower reintervention-free survival (62.5% [±6%] vs 92.9% [±0.9%]; P < .001). Matched analysis also revealed shorter length of stay (1 vs 7 days; P < .001), as well as lower pulmonary (1.2% vs 6.6%; P = .01), renal (1.8% vs 10%; P < .001), and cardiac (1.8% vs 12.8%; P < .001) complications among CERAB patients. ConclusionsCERAB had lower perioperative morbidity compared with ABF with a similar primary patency 1-year estimates. However, patients who underwent CERAB experienced more major adverse limb events and reinterventions. Although CERAB is an effective treatment for patients with AIOD, further studies are needed to determine the long-term outcomes of CERAB compared with the established durability of ABF and further define the role of CEARB in the treatment of AIOD.

Comparison of the Pre-Established and Finally Selected Treatment Strategies for Endovascular Treatment in Femoropopliteal Artery Lesions.

This study aimed to compare lower limb events associated with preplanned and finally selected treatment strategies-the validity and usefulness of the physician-chosen strategy were verified.We examined the data of 1003 patients in the registry of multicenter endovascular treatment for superficial femoral and popliteal artery disease study and prospectively enrolled patients who underwent endovascular treatment (EVT) of the femoropopliteal (FP) artery between February 2017 and June 2018 from 67 Japanese institutes. The outcome measures were major adverse limb events (MALE) and target vessel revascularization.The EVT strategies were classified into balloon angioplasty-alone (37.3%), primary stenting (26.7%), and provisional stenting (36.0%) groups. In the initial strategy analysis for the balloon angioplasty-alone, primary stenting, and provisional stenting groups, two-year rates of freedom from MALE (95% confidence interval) were 0.680 (0.620-0.732), 0.754 (0.688-0.808), and 0.798 (0.746-0.840), respectively. Additionally, the rate of MALE was significantly higher among patients in the balloon angioplasty-alone group than among those in the primary or provisional stenting groups in the initial strategy analysis (P = 0.007). Changes in treatment strategy were more frequent in the primary stenting group than in the other groups. Furthermore, the rate of MALE did not significantly differ among the three groups in the final strategy analysis (P = 0.56).Limb outcomes for the final applied strategy did not differ among the three strategies. Additionally, the physician's selection bias was mostly appropriate in the EVT of the FP artery.

Safety and Feasibility of the BYCROSS® Atherectomy Device for the Treatment of Femoropopliteal Arterial Obstructions: Single-Center Short-Term Outcomes.

Background: Endovascular techniques have gained preference over peripheral arterial bypass surgery due to their minimally invasive nature; however, endovascular treatments often show limited efficacy in arterial segments with a high atherosclerotic load. The use of atherectomy devices enables the removal of calcified plaque material and may promote arterial wall remodeling. This study assessed the technical success, safety, and feasibility of the BYCROSS® atherectomy device in femoropopliteal lesions. Methods: This single-center, retrospective cohort study analyzed elective patients undergoing BYCROSS® atherectomy for chronic peripheral arterial disease from March 2022 to May 2023. Patient data, procedural details, and outcomes were retrospectively collected from electronic patient records. The primary performance endpoints of this study were technical success, complications, and patency rates. Primary safety endpoints included 30-day and short-term major adverse limb events (MALEs), major adverse cardiovascular events (MACEs), and mortality rate. Results: The study included 19 patients (median age, 71 years; 63% male) with Fontaine class IIb (26%), III (21%), or IV (53%). The BYCROSS® atherectomy device was used to treat 22 limbs in the femoropopliteal tract, of which 11 lesions (50%) were occlusions and 11 were stenoses, with a median length of 24 cm (interquartile range: 17-38). Technical success was achieved in all cases: 4.5% required atherectomy only, 50% required additional balloon angioplasties, 41% required balloon angioplasties and stenting, and 4.5% required segments only stenting. Additional treatment of below-the-knee arteries was performed in 12 patients. Procedurally related complications (not limited to the use of the BYCROSS® device) occurred in 23% of limbs, including distal embolization and laceration. At 30 days, mortality was 5%, the MACE rate was 11%, and the MALE rate was 0%. The observed mortality rate was not directly related to the procedure. Patency (<50% restenosis at duplex ultrasound) was 83% at 30 days. Conclusions: The use of the BYCROSS® atherectomy device for the treatment of femoropopliteal lesions appears to be safe and feasible, with high technical success and low MALE and MACE rates in a challenging population with long-segment femoropopliteal lesions. Long-term follow-up in larger patient series is needed to confirm these findings and to determine the durability of this technique.

O57: Tailored risk assessment and forecasting in intermittent claudication using machine learning (TRAFIC-ML)

Abstract Introduction Guidelines recommend cardiovascular risk reduction and supervised exercise therapy as the initial treatment for patients with intermittent claudication(IC). However, implementation challenges and poor patient compliance lead to significant variation in management and therefore outcomes. We propose a precise machine learning derived decision support system that aims to provide personalised outcome predictions across different management strategies. Methods Feature selection was performed using the least absolute shrinkage and selection operator method. The model was developed using a bootstrapped sample of 10,000 patients based on 255 patients from our vascular centre. The model considered 27 baseline characteristics, compliance to best medical therapy/smoking cessation and treatment strategy. The model was validated using a separate dataset of 254 patients. This model was then used to build a prototype interactive decision support system which was evaluated using calibration curves, decision curve analyses and area under the receiver operator characteristic (AUROC) curves. Results The AUROC curves demonstrated excellent discrimination for the risk of progression to chronic limb threatening ischaemia at two years(0.892) and five years(0.866) and likelihood of major adverse cardiovascular events(0.836), major adverse limb events(0.891) and revascularisation(0.896)within 5 years, regardless of the treatment strategy. Calibration curves demonstrated good consistency between predicted and actual outcomes and decision curve analyses confirmed clinical utility. The tool maintained an accuracy of &amp;gt;80% and an effect size of &amp;gt;0.5. Conclusion Our decision support system successfully predicts outcomes in IC regardless of treatment strategy, offering potential for improved risk stratification and patient outcomes.

Machine Learning to Predict Outcomes of Endovascular Intervention for Patients With PAD

Endovascular intervention for peripheral artery disease (PAD) carries nonnegligible perioperative risks; however, outcome prediction tools are limited. To develop machine learning (ML) algorithms that can predict outcomes following endovascular intervention for PAD. This prognostic study included patients who underwent endovascular intervention for PAD between January 1, 2004, and July 5, 2023, with 1 year of follow-up. Data were obtained from the Vascular Quality Initiative (VQI), a multicenter registry containing data from vascular surgeons and interventionalists at more than 1000 academic and community hospitals. From an initial cohort of 262 242 patients, 26 565 were excluded due to treatment for acute limb ischemia (n = 14 642) or aneurysmal disease (n = 3456), unreported symptom status (n = 4401) or procedure type (n = 2319), or concurrent bypass (n = 1747). Data were split into training (70%) and test (30%) sets. A total of 112 predictive features (75 preoperative [demographic and clinical], 24 intraoperative [procedural], and 13 postoperative [in-hospital course and complications]) from the index hospitalization were identified. Using 10-fold cross-validation, 6 ML models were trained using preoperative features to predict 1-year major adverse limb event (MALE; composite of thrombectomy or thrombolysis, surgical reintervention, or major amputation) or death. The primary model evaluation metric was area under the receiver operating characteristic curve (AUROC). After selecting the best performing algorithm, additional models were built using intraoperative and postoperative data. Overall, 235 677 patients who underwent endovascular intervention for PAD were included (mean [SD] age, 68.4 [11.1] years; 94 979 [40.3%] female) and 71 683 (30.4%) developed 1-year MALE or death. The best preoperative prediction model was extreme gradient boosting (XGBoost), achieving the following performance metrics: AUROC, 0.94 (95% CI, 0.93-0.95); accuracy, 0.86 (95% CI, 0.85-0.87); sensitivity, 0.87; specificity, 0.85; positive predictive value, 0.85; and negative predictive value, 0.87. In comparison, logistic regression had an AUROC of 0.67 (95% CI, 0.65-0.69). The XGBoost model maintained excellent performance at the intraoperative and postoperative stages, with AUROCs of 0.94 (95% CI, 0.93-0.95) and 0.98 (95% CI, 0.97-0.99), respectively. In this prognostic study, ML models were developed that accurately predicted outcomes following endovascular intervention for PAD, which performed better than logistic regression. These algorithms have potential for important utility in guiding perioperative risk-mitigation strategies to prevent adverse outcomes following endovascular intervention for PAD.

Effect of a multidisciplinary team approach in patients with diabetic foot ulcers on major adverse limb events (MALEs): systematic review and meta-analysis for the development of the Italian guidelines for the treatment of diabetic foot syndrome.

The treatment of patients with diabetic foot ulcers (DFUs) is extremely complex, requiring a comprehensive approach that involves a variety of different healthcare professionals. Several studies have shown that a multidisciplinary team (MDT) approach is useful to achieve good clinical outcomes, reducing major and minor amputation and increasing the chance of healing. Despite this, the multidisciplinary approach is not always a recognized treatment strategy. The aim of this meta-analysis was to assess the effects of an MDT approach on major adverse limb events, healing, time-to-heal, all-cause mortality, and other clinical outcomes in patients with active DFUs. The present meta-analysis was performed for the purpose of developing Italian guidelines for the treatment of diabetic foot with the support of the Italian Society of Diabetology (Società Italiana di Diabetologia, SID) and the Italian Association of Clinical Diabetologists (Associazione Medici Diabetologi, AMD). The study was performed using the Grading of Recommendations Assessment, Development, and Evaluation approach. All randomized clinical trials and observational studies, with a duration of at least 26weeks, which compared the MDT approach with any other organizational strategy in the management of patients with DFUs were considered. Animal studies were excluded. A search of Medline and Embase databases was performed up until the May 1st, 2023. Patients managed by an MDT were reported to have better outcomes in terms of healing, minor and major amputation, and survival in comparison with those managed using other approaches. No data were found on quality of life, returning-to-walking, and emergency admission. Authors concluded that the MDT may be effective in improving outcomes in patients with DFUs.

Impact of hyperuricemia on 5-year clinical outcomes in patients with critical limb ischemia following percutaneous transluminal angioplasty.

A growing evidence on the correlation between hyperuricemia and cardiovascular disease (CVD) has been previously reported. However, there have been limited data on the impact of hyperuricemia on long-term clinical outcomes in patients with critical limb ischemia (CLI) who underwent percutaneous transluminal angioplasty (PTA). A total of 425 peripheral artery disease patients who underwent PTA for CLI were enrolled. The patients were divided into the hyperuricemia group (n = 101) and the normal group (n = 324). The primary endpoint was major adverse cerebral and cardiovascular event (MACCE), including death, myocardial infarction, any coronary revascularization, and stroke, up to 5 years. The secondary endpoint was a major adverse limb event (MALE), including any repeated PTA, and target extremity surgery. Inverse probability weighting (IPTW) analysis, derived from the logistic regression model, was performed to adjust for potential confounders. After IPTW matching analysis, compared to the normal group, the hyperuricemia group was associated with a higher incidence of MACCE (20.7% vs. 13.6%, hazard ratio [HR], 1.65; 95% confidence interval [CI], 1.15-2.38, P = 0.006) including non-cardiac death (11.7% vs. 6.3%, HR: 1.95, 95% CI: 1.19-3.19, P = 0.006) and MALE (47.7% vs. 36.0%, HR: 1.62, 95% CI: 1.23-2.13, P = 0.001) including non-target extremity revascularization (15.0% vs. 6.8%, HR: 2.42, 95% CI: 1.52-3.84, P < 0.001). In the present study, hyperuricemia was associated with worse clinical outcomes in patients with CLI following PTA during 5-year clinical follow-up. Efficacy of controlling hyperuricemia in improving clinical outcomes should be evaluated in further studies.

Prospective, Multi-center, Single-Arm Study of the Auryon Laser System for Treatment of Below-the-Knee Arteries in Patients With Chronic Limb-Threatening Ischemia: 30-Day Results of the Auryon BTK

The 355 nm Auryon laser has been shown to be effective and safe in treating various morphology lesions in the femoropopliteal arteries. There are limited data on the Auryon laser in treating below the knee (BTK) arteries in patients with chronic limb threatening ischemia (CLTI). We present the 30-day efficacy and safety findings from the ongoing Auryon BTK study.Patients with CLTI were prospectively enrolled in the Auryon BTK study between March 2022 and February 2023 in 4 US centers after obtaining informed consent. The primary safety endpoint included Major Adverse Limb Events (MALE) + Post-Operative Death (POD) at 30 days defined as a composite of all-cause death, major amputation and target vessel revascularization. Demographic, procedural, angiographic and outcome data were collected.A total of 60 patients (61 lesions) were treated. The mean age was 74.6 ± 10.3 years with 65.0 % males, 58.3% diabetics, 43.3% Rutherford Becker (RB) IV and 56.7% RB V. Of the 61 lesions, 59% had severe calcification, 31.1 % were chronic total occlusions and 90.2% were denovo disease. Baseline diameter stenosis was 80.2 ± 16.4%, post laser 57.4 ± 21.7% and post final treatment 24.0 ± 23.1% (p value < 0.0050). The primary performance endpoint showed a procedure success rate of 37/68 (63.8%). Bailout stenting occurred in 1/61 lesions (1.6%). Rutherford Becker category was 100% RB IV or higher at baseline versus 35.3% at 30-day. At 30 days, there was no target vessel revascularization and patency was 88.9% (PSVR ≤ 2.4). In conclusion, the Auryon laser is safe and relatively effective in treating BTK lesions with minimal complications.