Major Adverse Limb Events in Patients Undergoing Revascularisation for Lower Limb Peripheral Arterial Disease: A Nationwide Observational Study☠.

OBJECTIVE: Major adverse limb events (MALEs) are frequent in patients with lower extremity peripheral arterial disease (PAD). However, routine care MALE rate estimations after revascularisation are scarce. This study aimed to determine post-procedural MALE rates in revascularised patients with PAD and identify predictors for post-procedural MALEs. METHODS: This was a population based observational study on merged national registry data. Patients with PAD undergoing lower limb revascularisation between 2008 and 2016 were retrieved from the Swedish National Registry for Vascular Surgery. Information on comorbidities, medications, and post-procedural MALE endpoints were identified in national healthcare registries. Primary outcomes of interest were categorised as 2 - 4 point MALE composites that included limb amputation, acute lower limb ischaemia, progression to or relapse of chronic limb threatening ischaemia (CLTI), and ipsilateral re-interventions regardless of indication. Patients with intermittent claudication (IC) and CLTI were analysed separately using Kaplan-Meier estimates. Stepwise Cox proportional hazard models were used for predictor candidate analysis. RESULTS: Overall, 28 021 revascularised patients with PAD were analysed (IC, n = 10 506, 37.5%; CLTI, n = 17 515, 62.5%). During a mean follow up ± standard deviation of 3.2 ± 2.4 years, 5 226 (18.7%), 9 423 (33.6%), and 12 696 (45.3%) patients experienced a 2, 3, and 4 point MALE, respectively. The estimated one year 4 point MALE rates were 21.4% (95% confidence interval [CI] 20.6 - 22.2%) in IC and 46.9% (95% CI 46.1 - 47.7%) in CLTI. Adjusted predictors for experiencing a 4 point MALE in IC were chronic kidney disease (CKD) (hazard ratio [HR] 1.33, 95% CI 1.12 - 1.59) and previous lower limb revascularisation (HR 1.29, 95% CI 1.19 - 1.40). In CLTI, previous contralateral lower limb amputation (HR 1.60, 95% CI 1.47 - 1.73) and CKD (HR 1.25, 95% CI 1.17 - 1.34) were adjusted predictors. CONCLUSION: This study emphasises the very high MALE rates in revascularised patients with lower limb PAD, especially in CLTI. Prior lower limb revascularisation correlated with increased MALE rates in IC patients, while prior lower limb amputation was linked to subsequent MALEs in CLTI. In both IC and CLTI, CKD was associated with poorer outcomes, regardless of applied MALE definition.

Short and Mid Term Outcomes of Percutaneous Deep Venous Arterialisation for No-option Chronic Limb Threatening Ischaemia: A Systematic Review and Meta-Analysis.

OBJECTIVE: Percutaneous deep venous arterialisation (pDVA) is a state of the art technique for treating patients with chronic limb threatening ischaemia (CLTI) with no conventional option for revascularisation. There are limited large scale data examining the clinical effectiveness of pDVA for patients with end stage CLTI. DATA SOURCES: MEDLINE, Embase, Google Scholar, and Cochrane databases. REVIEW METHODS: Four databases were searched from January 2018 to June 2024 to identify studies investigating the feasibility and clinical outcomes of pDVA for patients with CLTI with no conventional revascularisation options. Meta-analysis of time to event outcomes (mean ± standard deviation) was performed for amputation free survival as the primary outcome, and freedom from amputation and overall survival as secondary outcomes. Other secondary outcomes (mean and 95% confidence interval [CI]) were procedural success rate, patency, re-intervention, and complete wound healing. RESULTS: Ten non-randomised studies were included with 351 patients. Mean patient age was 70.3 years, and 67.6% were male. Most procedures utilised the posterior tibial artery. The aggregated rate of amputation free survival at six and 12 months (five studies, 260 patients) was 72.6 ± 2.8% and 66.0 ± 3.1%, respectively, while the overall survival at six and 12 months (five studies, 260 patients) was 85.0 ± 2.3% and 77.7 ± 2.9%, respectively. The procedural success rate (nine studies, 330 patients) was 95.5% (95% CI 92.4 - 98.7%). Primary and secondary patency at six months (four studies, 241 patients) was 23.4% (95% CI 13.6 - 33.2%) and 54.9% (95% CI 34.3 - 75.5%), respectively. The rates of re-intervention (four studies, 190 patients) and complete wound healing (seven studies, 266 patients) at six and 12 months were 15.5% (95% CI 1.4 - 29.6%) and 41.7% (95% CI 25.7 - 57.7%), respectively, for re-intervention, and 19.3% (95% CI 9.6 - 29.0%) and 46.0% (95% CI 31.7 - 60.3%) for wound healing. CONCLUSION: This meta-analysis demonstrated acceptable feasibility for no-option CLTI at highly specialised institutions for patients undergoing pDVA. Meta-analysis of time to event outcomes revealed that pDVA provides reasonable amputation free survival for up to 12 months, albeit with a overall low certainty of evidence. Wider adoption of pDVA may be considered in selective patients with CLTI, although its clinical impact and cost effectiveness require further evaluation.

Recombinant Human Hepatocyte Growth Factor Plasmids for Treating Patients with Chronic Limb Threatening Ischaemia: A Systematic Review and Meta-analysis.

OBJECTIVE: Recombinant human hepatocyte growth factor (HGF) plasmids are novel alternatives to salvage limbs in patients with chronic limb threatening ischaemia (CLTI). A systematic review and meta-analysis of data were conducted to assess the therapeutic efficacy of HGF plasmids in patients with CLTI. DATA SOURCES: Randomised controlled studies evaluating HGF plasmid efficacy in patients with CLTI were identified using Medline, Embase, Cochrane Database of Systematic Reviews, and ClinicalTrials.gov databases. REVIEW METHODS: Meta-analyses of the reported relative risks (RR) or mean differences (MD) were conducted. Subgroup analyses determined the efficacy of HGF plasmids in cohorts excluding Buerger's disease. Certainty of evidence for each outcome was assessed. RESULTS: Seven studies (n = 655) were included. Based on low certainty evidence, patients treated with HGF had a significantly higher complete ulcer healing rate (RR 1.99, 95% CI 1.30 - 3.04; p = .015) than patients treated with placebo. The HGF treatment was associated with reduced visual analogue scale (VAS) scores of pain severity (MD -1.56, 95% CI -2.12 - -1.00; p < .001) vs. placebo in patients with CLTI assessed at the 3 month follow up (low certainty evidence); no significant differences were observed in major amputation (RR 0.91, 95% CI 0.48 - 1.73; p = .77) (low certainty evidence), or all-cause mortality (RR 0.93, 95% CI 0.38 - 2.27; p = .87) (low certainty evidence) between patients treated with HGF and placebo. Low certainty evidence suggested no significant differences in change in ankle-brachial index at 6 months (MD 0.00, 95% CI -0.09 - 0.09; p = 1.0) between patients treated with HGF and placebo. The complete ulcer healing rate and improved 3 month VAS scores of pain severity benefits persisted in subgroup analyses (low certainty evidence). CONCLUSION: Hepatocyte growth factor treatment is associated with an increased complete ulcer healing rate and reduced ischaemic pain in patients with CLTI.

Patient experience of the process to diagnosis of chronic limb-threatening ischaemia: A qualitative study.

INTRODUCTION: Delays exist at each stage of the chronic limb-threatening ischaemia (CLTI) care pathway, but there is little known about patient factors influencing delay to diagnosis of CLTI. This study explores the experiences and perceptions of patients recently diagnosed with CLTI. METHODS: A qualitative interview study was conducted. Sixteen participants underwent semi-structured interviews. Reflexive thematic analysis was performed on the data, aiming to understand factors which can influence delay in the CLTI care pathway. RESULTS: Five interrelated themes were developed: CLTI is a devastating condition; Reluctance to ask for help; When we are empowered we get better care; Luck plays a role in the process to diagnosis; and Vascular units can do better, comprising sub-themes of information transfer-consider communication and arterial versus non-arterial centres-proximity isn't everything. CONCLUSIONS: The five themes generated from the interview data describe factors relevant to delay given meaning by participants who have lived experience of CLTI. Theme content should be noted by clinicians, commissioners and providers looking to improve care pathways for patients with CLTI. The importance of awareness for the public, patients and clinicians linked ideas in some themes and interventions to raise awareness should be considered.

Percutaneous Closure Based on Physiological Assessment of an Arteriovenous Fistula in a Patient With Chronic Limb Threatening Ischaemia.

Introduction: An arteriovenous fistula (AVF) is a potential complication of endovascular therapy (EVT). Arteriovenous fistula steal syndrome sometimes leads to severe limb ischaemia; however, assessment of peripheral perfusion in AVF has not yet been established. Report: A 90 year old woman diagnosed with chronic limb threatening ischaemia underwent EVT. However, subintimal angioplasty of infrapopliteal lesions resulted in AVF formation in the posterior tibial artery (PTA). Revascularisation of the anterior tibial artery and PTA was performed, but severe AVF steal syndrome persisted and wound healing was delayed. An attempt to physiologically assess the effects of AVF closure and perform an AVF closing manoeuvre, if necessary, was performed. The physiological assessment was performed by laser Doppler flowmetry (LDF) and blood flow was temporarily blocked via the AVF at the distal PTA using a 6 F guiding extension catheter. A significant increase in blood flow was observed in the perfused area of the plantar artery. Coil embolisation and covered stent implantation in the PTA completely closed the AVF. During the procedure, peripheral perfusion with LDF gradually increased in the heel and fifth toe. After AVF closure, the skin perfusion pressure values increased significantly, wound healing was accelerated, and complete healing was achieved. Discussion: Laser Doppler flowmetry measurements under simulated AVF closure using a guiding extension catheter may be useful for the physiological assessment of peripheral perfusion before percutaneous AVF closure.

Bypass versus Angioplasty in Severe Ischaemia of the Leg (BASIL)-2 Trial: Analysis of the Timing and Causes of Death in Participants Randomised to an Infrapopliteal Vein Bypass or Best Endovascular Treatment First Revascularisation Strategy.

OBJECTIVE: The Bypass versus Angioplasty in Severe Ischaemia of the Leg (BASIL)-2 trial enrolled participants with chronic limb threatening ischaemia who required an infrapopliteal, with or without a femoropopliteal, revascularisation procedure to restore limb perfusion. Participants randomised to a vein bypass (VB) first revascularisation strategy were over one third more likely than those randomised to a best endovascular treatment (BET) first revascularisation strategy to die from any cause during a median follow up of 40.0 (interquartile range 20.9, 60.6) months. The aim was to describe the timing and causes of death in BASIL-2 as a first step towards trying to better understand why randomisation to a VB first revascularisation strategy was associated with this excess mortality. METHODS: A 10 person international panel comprising vascular and endovascular surgeons as well as vascular interventional radiologists, who had all been principal investigators in BASIL-2, took part in a modified Delphi consensus exercise to adjudicate the primary cause of death and, in particular, whether the cause was primarily cardiac or non-cardiac. RESULTS: In 151/168 deaths (89.9%) the Delphi panel achieved a consensus regarding the cause of death being probably cardiac or non-cardiac. In the BET group, 16/77 deaths (21%) were classified as probably cardiac compared with 32/91 (35%) in the VB group (unadjusted subdistribution hazard ratio 2.16, 95% confidence interval [CI] 1.20 - 3.87; unadjusted cause specific hazard ratio 2.15, 95% CI 1.19 - 3.90). At the point of randomisation, 64/344 (18.6%), 37/344 (10.8%), and 40/342 (9%) participants had a previous myocardial infarction (MI), percutaneous coronary intervention (PCI), and coronary artery bypass graft (CABG), respectively. There was no evidence of varying treatment effects for cause of death in subgroup analyses of previous PCI, CABG, or MI. CONCLUSION: The excess mortality observed in the VB first revascularisation strategy group in BASIL-2 was largely due to deaths that were adjudicated by the Delphi panel as probably primarily cardiac. These excess cardiac deaths were observed throughout follow up and there was no evidence of non-proportional hazards. Further work is ongoing to try to better understand the reasons for these findings.

Impact of Infrapopliteal Revascularisation Establishing In Line Flow to the Wound in Patients with Chronic Limb Threatening Ischaemia.

OBJECTIVE: This study aimed to determine the impact of infrapopliteal (IP) revascularisation establishing in line flow to the wound (IFW) on wound healing in chronic limb threatening ischaemia (CLTI), using a core laboratory assessment for wounds and in line flow. METHODS: The Wound-directed Angiosome RevasculaRIzation apprOach to patients with cRitical limb iSchaemia (WARRIORS) multicentre observational study enrolled patients with CLTI with tissue loss undergoing IP revascularisation in Japan, with scheduled two year follow up. The primary outcome measure was complete wound healing, defined as achievement of complete epithelialisation of all wounds without major amputation. IP revascularisation establishing IFW was defined as revascularisation after which a tibiopedal artery that actually fed an injured pedal unit was patent. The incidence of wound healing was compared between the IFW and non-IFW groups using inverse probability of treatment weighting based on the propensity score. RESULTS: A total of 440 patients with CLTI (median age, 75 years; male, 64.1%; diabetes mellitus, 72.0%; dialysis, 57.7%) with tissue loss (Wound, Ischemia, and foot Infection stage 4, 66.4%) who underwent IP revascularisation (endovascular procedure, n = 304; bypass grafting, n = 136) between October 2017 and June 2020 were registered. During a median follow up of 23.6 months, 51.1% achieved wound healing. Successful IP revascularisation with IFW was achieved in 68.2%. After analysis, the IFW group had a higher incidence of wound healing than the non-IFW group (34.5 vs. 16.1 per 100 person years; p = .030). The association of IFW with wound healing was not statistically different between patients undergoing bypass grafting and those undergoing an endovascular procedure (p for interaction = .38). There was no statistically significant interaction effect between IFW and direct revascularisation for wound healing (p for interaction = .51). CONCLUSION: IP revascularisation establishing IFW was statistically significantly associated with a higher wound healing rate in patients with CLTI.

The Incidence and Outcomes of Major Limb Amputation in New Zealand from 2010 to 2021.

Background: Major limb amputation (MLA) can be a common outcome due to severe peripheral artery disease (PAD) and diabetic foot disease (DFD), and it carries a significant mortality burden. In New Zealand (NZ), there is little documentation of the incidence rate and mortality after MLA. The aim was to report the national crude and standardised rates and the mortality post MLA. Methods: This retrospective observational study included all MLAs that occurred within NZ from 1/1/2010 to 31/12/2021 due to DFD and/or PAD. Two national databases (National Minimum Dataset and the Australasian Vascular Audit) were utilised. The crude rates were calculated as cases per 100,000 in the NZ population per year including all ages (using the 2013 and 2018 NZ census figures). The age-standardised rates used the World Health Organization standard population. Post-operative mortality was calculated from the date of first hospitalisation for MLA. Results: From 2010 to 2021, there were 5293 MLA procedures in 4242 patients. On average, there were 8.5 MLAs per week and 441.1 MLAs annually. The overall crude rate was 9.44 per 100,000, and the standardised rate was 6.12 per 100,000. Over the 12 years, the crude rate decreased by 22% (p < 0.001), and the standardised rate decreased by 20.4% (p < 0.001). After MLA, the 30-day and 1-year mortality was 9.5% and 29.6%, respectively. From 2010 to 2021, the relative reduction in 30-day mortality was 45.1% (p < 0.001), and the reduction in 1-year mortality was 24.5% (p < 0.001). Increasing age, female sex and end-stage renal failure were predictors of 30-day and 1-year mortality. Conclusions: A considerable number of MLAs occur in NZ, with substantial perioperative mortality; however, the national incidence rates and mortality have improved over the last 12 years. This data might serve as benchmark to further reduce MLAs and improve patient outcomes.

Antimicrobial resistance is not increasing in subsequent cases of ischaemic foot infections, a single-centre cohort from 2012 to 2021.

Patients with chronic limb-threatening ischaemia (CLTI) are at risk of foot infections, which is associated with an increase in amputation rates. The use of antibiotics may lead to a higher incidence of antimicrobial resistance (AMR) in subsequent episodes of ischaemic foot infections (IFI). This retrospective single-centre cohort study included 130 patients with IFI undergoing endovascular revascularisation. Staphylococcus aureus and Pseudomonas aeruginosa were the two most common pathogens, accounting for 20.5% and 10.8% of cases, respectively. The prevalence of antimicrobial resistance (AMR) and multi-drug resistance did not significantly increase between episodes (10.2% vs. 13.4%, p = 0.42). In 59% of subsequent episodes, the identified pathogens were unrelated to the previous episode. However, the partial concordance of identified pathogens significantly increased to 66.7% when S. aureus was identified (p = 0.027). Subsequent episodes of IFI in the same patient are likely to differ in causative pathogens. However, in the case of S. aureus, the risk of reinfection, particularly with S. aureus, is increased. Multi-drug resistance does not appear to change between IFI episodes. Therefore, recommendations for empirical antimicrobial therapy should be based on local pathogen and resistance statistics without the need to broaden the spectrum of antibiotics in subsequent episodes.

Magnetic Resonance Imaging and Histological Insights Into Deep Venous Arterialisation.

Introduction: Percutaneous deep venous arterialisation (DVA) is emerging as a promising alternative for limb salvage in chronic limb threatening ischaemia (CLTI) patients without any reasonable anatomical option for conventional revascularisation techniques. However, its mechanism of action remains incompletely understood. This report aimed to find some of the histological alterations occurring in the limb following DVA. Report: This short report presents the case of a 53 year old female who underwent DVA for Rutherford 5 CLTI. Although the intervention was successful and showed evidence of improved blood flow to the foot, the post-operative course was notable due to worsening infection leading to a below knee amputation four weeks later. The blood vessels were harvested for histological analysis, which found features of venous arterialisation such as smooth muscle cell proliferation and neointimal hyperplasia, even in the paired posterior tibial vein that did not undergo DVA. Discussion: This case demonstrated unexpected histological changes occurring in the paired posterior tibial vein that did not undergo DVA. This warrants further investigations to fully understand the mechanisms at play in DVA and to explore the role of the paired vein in sustaining arterialised flow to the foot.

New Horizons in Peripheral Artery Disease.

Peripheral artery disease (PAD) is the lower limb manifestation of systemic atherosclerotic disease. PAD may initially present with symptoms of intermittent claudication, whilst chronic limb-threatening ischaemia (CLTI), the end stage of PAD, presents with rest pain and/or tissue loss. PAD is an age-related condition present in over 10% of those aged ≥65 in high-income countries. Guidelines regarding definition, diagnosis and staging of PAD and CLTI have been updated to reflect the changing patterns and presentations of disease given the increasing prevalence of diabetes. Recent research has changed guidelines on optimal medical therapy, with low-dose anticoagulant plus aspirin recommended in some patients. Recently published randomised trials highlight where bypass-first or endovascular-first approaches may be optimal in infra-inguinal disease. New techniques in endovascular surgery have increased minimally invasive options for ever more complex disease. Increasing recognition has been given to the complexity of patients with CLTI where a high prevalence of both frailty and cognitive impairment are present and a significant burden of multi-morbidity and polypharmacy. Despite advances in minimally invasive revascularisation techniques and reduction in amputation incidence, survival remains poor for many with CLTI. Shared decision-making is essential, and conservative management is often appropriate for older patients. There is emerging evidence of the benefit of specialist geriatric team input in the perioperative management of older patients undergoing surgery for CLTI. Recent UK guidelines now recommend screening for frailty, cognitive impairment and delirium in older vascular surgery patients as well as recommending all vascular surgery services have support and input from specialist geriatrics teams.

The Utility of Sirolimus Eluting Balloons in the Setting of Chronic Limb Threatening Ischaemia in Asian Patients from Singapore - 12 Months Results of the PRISTINE Registry.

PURPOSE: The aim of PRISTINE was to evaluate the 6 and 12 months safety and efficacy of the Selution Sustained Limus Release (SLR)™ sirolimus-coated balloon for treatment of complex lower limb occlusive lesions (TASC II C & D) in patients with chronic limb threatening ischemia (CLTI) from Singapore. METHODS: PRISTINE was a prospective, non-randomized, single arm, observational, multi-investigator, single-center clinical study. Complication-free survival at 30 days was the safety clinical endpoint. Immediate technical success (ability to cross and dilate the lesion and achieve residual angiographic stenosis < 30%), 6-month primary vessel patency, limb salvage, clinically driven target lesion revascularization (TLR) and amputation free survival (AFS) were the efficacy endpoints of interest. RESULTS: Seventy five patients were included. There were 50 (68.0%) males; mean age, 69.0 ± 10.7 years. CLTI severity was based on the Rutherford Scale (R5 = 51; R6 = 17). Significant co-morbidities included diabetes mellitus (n = 68; 91.0%) and end-stage renal failure (n = 28; 37.0%). 112 atherosclerotic lesions were treated (TASC II D = 58 (52%); 76 (67%) de novo). There was 100% technical success. Mean lesion length treated was 22.4 ± 13.9 cm. Primary vessel patencies at 6 and 12 months were 64/86 (74%) and 43/74 (58%) and freedom from clinically driven TLR were 72/86 (84%) and 55/74 (74%) respectively. AFS was 61/73 (84.0%; five deaths and seven major lower extremity amputation) at 6-months. Mean Rutherford score improved from 5.1 ± 0.55 at baseline to 1.1 ± 2.05 (p < 0.05) at one year and there was a wound healing rate of 38/48 (79%) at the same timepoint. CONCLUSIONS: The Selution SLR™ drug eluting balloon is safe and efficacious in treating highly complex infra-inguinal atherosclerotic lesions in an otherwise challenging frail population of CLTI patients with a high incidence of diabetes and end-stage renal failure. It is associated with highly satisfactory acute technical and clinical success, 12-month target lesion patency and AFS. LEVEL OF EVIDENCE: Level 2b, Individual Cohort Study.

Reduction of Major Amputations after Surgery Versus Endovascular Intervention: The BEST-CLI Randomised Trial.

OBJECTIVE: BEST-CLI, an international randomised trial, compared bypass surgery with endovascular treatment in chronic limb threatening ischaemia (CLTI). In this substudy, overall amputation rates and risk of major amputation as an initial or subsequent outcome were evaluated. METHODS: A total of 1 830 patients were randomised to receive surgical or endovascular treatment:(1) patients with adequate single segment great saphenous vein (SSGSV) (n = 1 434); and (2) patients without adequate SSGSV (n = 396). Differences in time to first event and number of amputations were evaluated. RESULTS: In cohort 1, 410 (45.6%) total amputation events occurred in the surgical group vs. 490 (54.4%) in the endovascular group (p = .001) during mean follow up of 2.7 years. Every third patient underwent minor amputation after index revascularisation: 31.5% of the surgical group vs. 34.9% in the endovascular group (p = .17). Subsequent major amputation was required significantly less often in the surgical group compared with the endovascular group (15.0% vs. 25.6%; p = .002). The first amputation was major in 5.6% of patients in the surgical and 6.0% in the endovascular group (p = .72). Major amputation was required in 10.3% (n = 74/718) of patients in the surgical group and 14.9% (n = 107/716) in the endovascular group (p = .008). In cohort 2, 199 amputation events occurred in 132 (33.3%) patients during mean follow up of 1.6 years: 95 (47.7%) in the surgical vs. 104 (52.3%) in the endovascular group (p = .49). Major amputation was required in 15.2% (n = 30/197) of the patients in the surgical and 14.1% (n = 28/199) in the endovascular group (p = .74). CONCLUSION: In patients with CLTI, surgical bypass with SSGSV was more effective than endovascular treatment in preventing major amputations because of a decrease in major amputations subsequent to minor amputations.

Association of Pedal Acceleration Time With Healing and Amputation Free Survival in Patients With Ulceration and Gangrene.

OBJECTIVE: Pedal acceleration time (PAT) is a novel non-invasive perfusion measurement that may be useful in the management of patients with ulceration and gangrene. The objective of this study was to report the association between PAT and wound healing, amputation free survival (AFS), and mortality at one year. METHODS: This prospective observational study reviewed all patients who underwent PAT after presentation with ulceration or gangrene from 1 January 2020 to 30 June 2022. PAT was defined as the time (in milliseconds) from the onset of systole to the peak of systole in the mid artery. The final PAT of a limb was used to assess outcomes (presenting PAT if no revascularisation, or post-revascularisation PAT). Wound healing, major limb amputation, and death at one year were collected. Healing was assessed with Fine-Gray competing risks model, AFS via logistic regression, and survival using Cox proportional hazards model. RESULTS: Overall, 265 patients (307 limbs) were included. The median patient age was 71 years and 74.0% (196/265) had diabetes mellitus. Patient demographics were similar among the final PAT category cohorts. Compared with a final PAT category 1, analysis of one year outcomes showed that the final PAT categories 2 - 4 had lower wound healing (category 2, hazard ratio [HR] 0.62, 95% confidence interval [CI] 0.43 - 0.9, p = .012; category 3, HR 0.21, 95% CI 0.08 - 0.58, p = .002; category 4, HR 0.12, 95% CI 0.04 - 0.34, p < .001), lower AFS (category 2, odds ratio [OR] 2.86, 95% CI 1.64 - 5.0, p < .001; category 3, OR 5.1, 95% CI 1.71 - 15.22, p = .003; category 4, OR 12.59, 95% CI 4.34 - 36.56, p < .001), and lower survival (category 2, HR 1.89, 95% CI 1.17 - 3.03, p =.009; category 3, HR 2.37, 95% CI 1.05 - 5.36, p = .039; category 4, HR 4.52, 95% CI 2.48 - 8.21, p < .001). CONCLUSION: The final PAT measurement is associated with wound healing, AFS, and death at one year. PAT may be a valuable tool to assess perfusion of the foot.

Network Meta-analysis of Randomised Controlled Trials Comparing the Outcomes of Different Endovascular Revascularisation Treatments for Infra-inguinal Peripheral Arterial Disease Causing Chronic Limb Threatening Ischaemia.

OBJECTIVE: The aim of this study was to compare the efficacy of different endovascular revascularisation procedures for treating chronic limb threatening ischaemia (CLTI) using network meta-analysis (NMA). DATA SOURCES: The databases PubMed and Cochrane Central Register for Controlled Trials were searched on 14 March 2023. REVIEW METHODS: A NMA of randomised controlled trials (RCTs) reporting the efficacy of different endovascular revascularisation techniques for treating CLTI was performed according to PRISMA guidelines. The primary and secondary outcomes were major amputation and death, respectively. Random effects models were developed and the results were presented using surface under the cumulative ranking curve plots and forest plots. A p value of ≤ .050 was considered statistically significant. The Cochrane collaborative tool was used to assess risk of bias. RESULTS: A total of 2 655 participants of whom 94.8% had CLTI were included. Eleven trials compared plain balloon angioplasty (PBA) vs. drug coated balloon (DCB) angioplasty (n = 1 771), five trials compared bare metal stent (BMS) vs. drug coated stent (DCS) (n = 466), three trials compared atherectomy vs. DCB (n = 194), two trials compared PBA vs. BMS (n = 70), one trial compared PBA vs. atherectomy (n = 50), and one trial compared BMS vs. DCB (n = 104). None of the revascularisation strategies significantly reduced the risk of major amputation or death compared with PBA. Using the network estimates, GRADE certainty of evidence for improvement in major amputation outcomes for DCB was moderate, for atherectomy and BMS was low, and for DCS was very low compared with PBA. Risk of bias was low in 16 trials, of some concerns in six trials, and high in one trial, respectively. CONCLUSION: There is no current evidence from RCTs to reliably conclude that BMS, DCB, DCS, or atherectomy are superior to PBA in preventing major amputation and death in patients with CLTI. Larger comparative RCTs are needed to identify the best endovascular revascularisation strategy.

Understanding delays in chronic limb-threatening ischaemia care: Application of the theoretical domains framework to identify factors affecting primary care clinicians' referral behaviours.

INTRODUCTION: Patients in the community with suspected Chronic limb-threatening ischaemia (CLTI) should be urgently referred to vascular services for investigation and management. The Theoretical Domains Framework (TDF) allows identification of influences on health professional behaviour in order to inform future interventions. Here, the TDF is used to explore primary care clinicians' behaviours with regards to recognition and referral of CLTI. METHODS: Semi-structured interviews were conducted with 20 podiatrists, nurses and general practitioners in primary care. Directed content analysis was performed according to the framework method. Utterances were coded to TDF domains, and belief statements were defined by grouping similar utterances. Relevance of domains was confirmed according to belief frequency, presence of conflicting beliefs and the content of the beliefs indicating relevance. RESULTS: Nine TDF domains were identified as relevant to primary care clinicians: Knowledge, Environmental context and resources, Memory, Decision and attention processes, Beliefs about capabilities, Skills, Emotions, Reinforcement and Behavioural regulation. Relationships across domains were identified, including how primary care clinician confidence and working in a highly pressurized environment can affect behaviour. CONCLUSION: We have identified key barriers and enablers to timely recognition and referral behaviour. These beliefs identify targets for theory-driven behaviour change interventions to reduce delays in CLTI pathways.

The BioMimics 3D Helical Centreline Nitinol Stent in Chronic Limb Threatening Ischaemia and Complex Lesions: Three Year Outcomes of the MIMICS-3D Registry.

OBJECTIVE: There is a need for improved outcomes in the endovascular treatment of patients suffering from chronic limb threatening ischaemia (CLTI), highly calcified lesions, and chronic total occlusions (CTOs). The helical centreline self expanding BioMimics 3D stent might be particularly useful in these high risk subsets, combining flexibility and fracture resistance with radial strength. Herein, the performance of the BioMimics 3D stent was assessed in these high risk subsets. METHODS: MIMICS-3D is a prospective, multicentre, European real world registry. This was a post hoc analysis, comparing patients with CLTI vs. intermittent claudication (IC), lesions with bilateral calcification vs. those without (peripheral arterial calcium scoring system [PACSS] 3,4 vs. PACSS 0 - 2), and CTO vs. no CTO. Propensity score matching was performed to reduce the impact of baseline variables. The 36 month endpoints were clinically driven target lesion revascularisation (CD-TLR), death, major target limb amputation, and stent patency. RESULTS: A total of 507 patients were enrolled. At 36 months, patients with CLTI had lower freedom from major amputation than patients with IC (92.6% vs. 100%, p < .001). In terms of primary patency, patients with CTO had lower patency rates than those without (63.9% vs. 77.8%, p = .003), but the difference reduced after propensity score matching (70.5% vs. 76.8%, p = .43). Primary patency was not impaired for patients with PACSS 3,4 or patients with CLTI. Freedom from CD-TLR was not significantly different among the groups and was 73.8% for CLTI vs. 78.9% for IC (p = .15), 77.6% for PACSS 3,4 vs. 78.7% for PACSS 0 - 2 (p = .55), and 75.6% for CTO vs. 81.0% for no CTO (p = .11). CONCLUSIONS: The outcome of the MIMICS-3D registry suggests that the BioMimics 3D stent is effective in the endovascular treatment of complex femoropopliteal lesions and in CLTI. Future randomised controlled trials should confirm its non-inferiority or superiority compared with existing alternatives.

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

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

Critical Limb Ischaemia in Octogenarians: Treatment Outcomes Compared With Younger Patients.

Objective: A growing proportion of patients with chronic limb threatening ischaemia (CLTI) are elderly, the most challenging for management decisions. The aim was to study the patient profile and outcome of CLTI in octogenarian patients, comparing them with younger patients. Methods: Retrospective cohort of consecutive patients hospitalised for CLTI with infrainguinal disease in a Spanish centre (2013-2020). Data on age, comorbidity, anatomical characteristics, and treatment were gathered. Patients were stratified according to age (<80 and ≥80 years). The primary outcomes were overall survival and limb salvage (LS), analysed using Kaplan-Meier and Cox regression. Results: : A total of 512 patients were enrolled: 305 were <80 years old with mean age 69.7 ± standard deviation (SD) 8.2 years, and 207 were ≥80 years old with mean age 85.3 ± SD 3.6 years. Smoking and diabetes mellitus were more frequent in younger patients (78.0% vs. 45.4%, p < .001; 68.5% vs. 59.5%, p = .037 respectively). Older patients had a higher prevalence of heart and kidney disease (70.5% vs. 57.0%, p = .002; 39.6% vs. 24.3%, p < .001, respectively). The arterial disease was femoropopliteal or tibial in 68.9% and 31.1% in patients <80 years and 58.9% and 41.1% in patients ≥80 years (p = .021). In younger patients, conservative treatment was indicated in 18.0%, endovascular treatment (ET) in 41.6%, and open or hybrid surgery (OS) in 40.3%; in patients ≥80 years these were 36.9%, 37.4%, and 25.7%, respectively (p <. 001). Mean follow up was 23.3 ± SD 17.4 months. One and two year overall survival was 85.4% and 73.0% in younger patients and 64.1% and 51.3% in patients ≥80 years (p < .001). LS was 83.7% and 79% at the same times in younger patients and 75.3% and 72.1% in older ones (p = .045). In younger patients ET led to worse LS than OS (p = .005) but not in older patients (p = .29). Conclusion: Patients ≥80 years with CLTI have higher comorbidity and lower life expectancy and receive conservative treatment more frequently than younger patients. ET and OS are associated with similar survival and LS in these older patients.