A vein bypass first versus a best endovascular treatment first revascularisation strategy for patients with chronic limb threatening ischaemia who required an infra-popliteal, with or without an additional more proximal infra-inguinal revascularisation procedure to restore limb perfusion (BASIL-2): an open-label, randomised, multicentre, phase 3 trial.

BACKGROUND: Chronic limb-threatening ischaemia is the severest manifestation of peripheral arterial disease and presents with ischaemic pain at rest or tissue loss (ulceration, gangrene, or both), or both. We compared the effectiveness of a vein bypass first with a best endovascular treatment first revascularisation strategy in terms of preventing major amputation and death in patients with chronic limb threatening ischaemia who required an infra-popliteal, with or without an additional more proximal infra-inguinal, revascularisation procedure to restore limb perfusion. METHODS: Bypass versus Angioplasty for Severe Ischaemia of the Leg (BASIL)-2 was an open-label, pragmatic, multicentre, phase 3, randomised trial done at 41 vascular surgery units in the UK (n=39), Sweden (n=1), and Denmark (n=1). Eligible patients were those who presented to hospital-based vascular surgery units with chronic limb-threatening ischaemia due to atherosclerotic disease and who required an infra-popliteal, with or without an additional more proximal infra-inguinal, revascularisation procedure to restore limb perfusion. Participants were randomly assigned (1:1) to receive either vein bypass (vein bypass group) or best endovascular treatment (best endovascular treatment group) as their first revascularisation procedure through a secure online randomisation system. Participants were excluded if they had ischaemic pain or tissue loss considered not to be primarily due to atherosclerotic peripheral artery disease. Most vein bypasses used the great saphenous vein and originated from the common or superficial femoral arteries. Most endovascular interventions comprised plain balloon angioplasty with selective use of plain or drug eluting stents. Participants were followed up for a minimum of 2 years. Data were collected locally at participating centres. In England, Wales, and Sweden, centralised databases were used to collect information on amputations and deaths. Data were analysed centrally at the Birmingham Clinical Trials Unit. The primary outcome was amputation-free survival defined as time to first major (above the ankle) amputation or death from any cause measured in the intention-to-treat population. Safety was assessed by monitoring serious adverse events up to 30-days after first revascularisation. The trial is registered with the ISRCTN registry, ISRCTN27728689. FINDINGS: Between July 22, 2014, and Nov 30, 2020, 345 participants (65 [19%] women and 280 [81%] men; median age 72·5 years [62·7-79·3]) with chronic limb-threatening ischaemia were enrolled in the trial and randomly assigned: 172 (50%) to the vein bypass group and 173 (50%) to the best endovascular treatment group. Major amputation or death occurred in 108 (63%) of 172 patients in the vein bypass group and 92 (53%) of 173 patients in the best endovascular treatment group (adjusted hazard ratio [HR] 1·35 [95% CI 1·02-1·80]; p=0·037). 91 (53%) of 172 patients in the vein bypass group and 77 (45%) of 173 patients in the best endovascular treatment group died (adjusted HR 1·37 [95% CI 1·00-1·87]). In both groups the most common causes of morbidity and death, including that occurring within 30 days of their first revascularisation, were cardiovascular (61 deaths in the vein bypass group and 49 in the best endovascular treatment group) and respiratory events (25 deaths in the vein bypass group and 23 in the best endovascular treatment group; number of cardiovascular and respiratory deaths were not mutually exclusive). INTERPRETATION: In the BASIL-2 trial, a best endovascular treatment first revascularisation strategy was associated with a better amputation-free survival, which was largely driven by fewer deaths in the best endovascular treatment group. These data suggest that more patients with chronic limb-threatening ischaemia who required an infra-popliteal, with or without an additional more proximal infra-inguinal, revascularisation procedure to restore limb perfusion should be considered for a best endovascular treatment first revascularisation strategy. FUNDING: UK National Institute of Health Research Health Technology Programme.

Editor's Choice - Bypass versus Angioplasty for Severe Ischaemia of the Leg (BASIL) Prospective Cohort Study and the Generalisability of the BASIL-2 Randomised Controlled Trial.

OBJECTIVE: The Bypass versus Angioplasty in Severe Ischaemia of the Leg-2 (BASIL-2) randomised controlled trial has shown that, for patients with chronic limb threatening ischaemia (CLTI) who require an infrapopliteal (IP) revascularisation a vein bypass (VB) first revascularisation strategy led to a 35% increased risk of major amputation or death when compared with a best endovascular treatment (BET) first revascularisation strategy. The study aims are to place the BASIL-2 trial within the context of the CLTI patient population as a whole and to investigate the generalisability of the BASIL-2 outcome data. METHODS: This was an observational, single centre prospective cohort study. Between 24 June 2014 and 31 July 2018, the BASIL Prospective Cohort Study (PCS) was performed which used BASIL-2 trial case record forms to document the characteristics, initial and subsequent management, and outcomes of 471 consecutive CLTI patients admitted to an academic vascular centre. Ethical approval was obtained, and all patients provided fully informed written consent. Follow up data were censored on 14 December 2022. RESULTS: Of the 238 patients who required an infrainguinal revascularisation, 75 (32%) had either IP bypass (39 patients) or IP BET (36 patients) outside BASIL-2. Seventeen patients were initially randomised to BASIL-2. A further three patients who did not have an IP revascularisation as their initial management were later randomised in BASIL-2. Therefore, 95/471 (20%) of patients had IP revascularisation (16% outside, 4% inside BASIL-2). Differences in amputation free survival, overall survival, and limb salvage between IP bypass and IP BET performed outside BASIL-2 were not subject to hypothesis testing due to the small sample size. Reasons for non-randomisation into the trial were numerous, but often due to anatomical and technical considerations. CONCLUSION: CLTI patients who required an IP revascularisation procedure and were subsequently randomised into BASIL-2 accounted for a small subset of the CLTI population as a whole. For a wide range of patient, limb, anatomical and operational reasons, most patients in this cohort were deemed unsuitable for randomisation in BASIL-2. The results of BASIL-2 should be interpreted in this context.

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 of the present study 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 of 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 of 77 deaths (21%) were classified as probably cardiac compared with 32 of 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 of 344 (18.6%), 40 of 342 (11.7%), and 37 of 344 (10.8%) 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.

Editor's Choice - A Comparison of Clinical Outcomes Between Primary Bypass and Secondary Bypass After Failed Plain Balloon Angioplasty in the Bypass versus Angioplasty for Severe Ischaemia of the Limb (BASIL) Trial.

OBJECTIVE: Chronic limb threatening ischaemia (CLTI) is a growing global health problem. The UK NIHR HTA funded BASIL trial is still the only randomised controlled trial to have compared a "bypass surgery first" with a "plain balloon angioplasty (PBA) first" strategy for the management of CLTI. In patients who were likely to survive for 2 years and had a suitable vein, primary bypass (PB) was associated with better clinical outcomes. Furthermore, PBA was associated with a high technical and clinical failure rate and many went on to have secondary bypass (SB). This study aimed at comparing clinical outcomes following PB and SB in the BASIL trial. METHODS: Demographic, procedural, and outcome data were obtained from the BASIL case report forms. Outcomes were amputation free survival (AFS), limb salvage (LS), overall survival (OS), and freedom from revascularisation (FFR). The SB cohort comprises patients whose first trial intervention was PBA and who subsequently underwent bypass during follow up. The PB cohort comprises those patients whose first trial intervention was bypass. RESULTS: The 190 PB and 49 SB patients were well matched except that the SB patients were more likely to be current smokers. At a median of 7 years, PB was associated with better AFS (PB 60% vs. SB 40%; HR 1.58, p = .04), LS (PB 85% vs. SB 73%, p = .06), and OS (PB 68% vs. 51%, p = .06). FFR was equivalent (PB 53% vs. 53%, p = .3). CONCLUSION: In the BASIL trial, clinical outcomes following PB were significantly better than in patients undergoing SB after failed PBA. Prior to treating patients with CLTI with primary PBA, clinicians should consider that if this should fail, the outcome of attempted subsequent bypass is likely to be significantly worse than if PB were attempted.

Vein bypass first vs. best endovascular treatment first revascularisation strategy for chronic limb-threatening ischaemia due to infra-popliteal disease: the BASIL-2 RCT.

Background: Chronic limb-threatening ischaemia with ischaemic pain and/or tissue loss. Objective: To examine the clinical and cost-effectiveness of a vein bypass-first compared to a best endovascular treatment-first revascularisation strategy in preventing major amputation or death. Design: Superiority, open, pragmatic, multicentre, phase III randomised trial. Setting: Thirty-nine vascular surgery units in the United Kingdom, and one each in Sweden and Denmark. Participants: Patients with chronic limb-threatening ischaemia due to atherosclerotic peripheral arterial disease who required an infra-popliteal revascularisation, with or without an additional more proximal infra-inguinal revascularisation procedure, to restore limb perfusion. Interventions: A vein bypass-first or a best endovascular treatment-first infra-popliteal, with or without an additional more proximal infra-inguinal revascularisation strategy. Main outcome measures: The primary outcome was amputation-free survival. Secondary outcomes included overall survival, major amputation, further revascularisation interventions, major adverse limb event, health-related quality of life and serious adverse events. Methods: Participants were randomised to a vein bypass-first or a best endovascular treatment-first revascularisation strategy. The original sample size of 600 participants (247 events) was based on a hazard ratio of 0.66 with amputation-free survival rates of 0.72, 0.62, 0.53, 0.47 and 0.35 in years 1-5 in the best endovascular treatment-first group with 90% power and alpha at p = 0.05. The sample size was revised to an event-based approach as a result of increased follow-up time due to slower than anticipated recruitment rates. Participants were followed up for a minimum of 2 years. A cost-effectiveness analysis was employed to estimate differences in total hospital costs and amputation-free survival between the groups. Additionally, a cost-utility analysis was carried out and the total cost and quality-adjusted life-years, 2 and 3 years after randomisation were used. Results: Between 22 July 2014 and 30 November 2020, 345 participants were randomised, 172 to vein bypass-first and 173 to best endovascular treatment-first. Non-amputation-free survival occurred in 108 (63%) of 172 patients in the vein bypass-first group and 92 (53%) of 173 patients in the best endovascular treatment-first group [adjusted hazard ratio 1.35 (95% confidence interval 1.02 to 1.80); p = 0.037]. Ninety-one (53%) of 172 patients in the vein bypass-first group and 77 (45%) of 173 patients in the best endovascular treatment-first group died [adjusted hazard ratio 1.37 (95% confidence interval 1.00 to 1.87)]. Over follow-up, the economic evaluation discounted results showed that best endovascular treatment-first was associated with £1690 less hospital costs compared to vein bypass-first. The cost utility analysis showed that compared to vein bypass-first, best endovascular treatment-first was associated with £224 and £2233 less discounted hospital costs and 0.016 and 0.085 discounted quality-adjusted life-year gain after 2 and 3 years from randomisation. Limitations: Recruiting patients to the Bypass versus Angioplasty in Severe Ischaemia of the Leg Trial-2 trial was difficult and the target number of events was not achieved. Conclusions: A best endovascular treatment-first revascularisation strategy was associated with better amputation-free survival, which was largely driven by fewer deaths. Overall, the economic evaluation results suggest that best endovascular treatment-first dominates vein bypass-first in the cost-effectiveness analysis and cost-utility analysis as it was less costly and more effective than a vein bypass-first strategy. Future work: The Bypass versus Angioplasty in Severe Ischaemia of the Leg Trial-2 investigators have a data sharing agreement with the BEst Surgical Therapy in patients with Chronic Limb threatening Ischaemia investigators. One output of this collaboration will be an individual patient data meta-analysis. Study registration: Current Controlled Trials ISRCTN27728689. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 12/35/45) and is published in full in Health Technology Assessment; Vol. 28, No. 65. See the NIHR Funding and Awards website for further award information.

Atherosclerosis, or narrowing of the arteries, can occur as a result of smoking, high blood pressure, diabetes, or high cholesterol in the blood. Atherosclerosis can affect any artery, including those supplying the legs, where the condition is called peripheral arterial disease. The most severe form of peripheral arterial disease is chronic limb-threatening ischaemia which can cause severe pain in the foot as well as ulcers and gangrene. Unless the blood supply to the leg and foot is improved, by a process called revascularisation, people with chronic limb-threatening ischaemia are at high risk of amputation and death. The blood supply can be improved by using a vein from the leg to bypass around the blockages (vein bypass) or by using a balloon (angioplasty) or small metal tubes (stents) to reopen the blocked arteries (best endovascular treatment). There is debate about which type of revascularisation is best in terms of preventing amputation and death, especially in people who need revascularisation of the arteries below the knee. Bypass versus Angioplasty in Severe Ischaemia of the Leg Trial-2 is the first randomised controlled trial to compare vein bypass-first and best endovascular treatment-first in this group of patients. Bypass versus Angioplasty in Severe Ischaemia of the Leg Trial-2 found that people randomised to a vein bypass-first revascularisation strategy were 35% more likely to require a major amputation or die than those randomised to a best endovascular treatment-first strategy. Most of this difference in favour of best endovascular treatment-first was due to a higher number of patients dying in the vein bypass-first group. Best endovascular treatment-first was also cheaper for the National Health Service. The results of this study suggest that in patients with chronic limb-threatening ischaemia due to peripheral arterial disease in the arteries below the knee, who are suitable for both vein bypass and best endovascular treatment and where there is uncertainty as to which is best, best endovascular treatment should be offered first rather than vein bypass.

A Comparison of Contemporary Clinical Outcomes Following Femoro-Popliteal Plain Balloon Angioplasty and Bypass Surgery for Chronic Limb Threatening Ischemia.

INTRODUCTION: Despite the BASIL-1 trial concluding that bypass surgery (BS) was superior to plain balloon angioplasty (PBA) in terms of longer-term amputation free (AFS) and overall survival (OS), CLTI patients are increasingly offered an endovascular-first revascularization strategy. This study investigates whether the results of BASIL-1 are still relevant to current practice by comparing femoro-popliteal (FP) BS with PBA in a series of CLTI patients treated in our unit 10 years after BASIL-1 (1999-2004). METHODS: We retrospectively analyzed prospectively gathered hospital data pertaining to 279 patients undergoing primary FP BS or PBA for CLTI in the period 2009 to 2014. We report baseline characteristics, 30-day morbidity and mortality, major adverse cardiovascular events (MACE) and long-term AFS, limb salvage (LS), OS, major adverse limb events (MALE), and freedom from re-intervention (FFR). RESULTS: 234 (84%) and 45 (16%) patients underwent PBA and BS respectively. PBA patients were significantly older (77 vs 71 years, P = 0.001) and more likely to be female (45% vs 28%, P = 0.026). Bollinger and GLASS anatomic scores were significantly more severe in the BS group. Technical success was better for BS (100% vs 87%, P = 0.007). Index hospital stay was shorter for PBA (9.1 vs 15.6 days, P = 0.035) but there was no difference in hospital days or admissions over the next 12 months. AFS (HR 1.00), LS (HR 1.44), OS (HR 0.81), MALE (HR 1.25) and FFR (HR = 1.00) were not significantly different between PBA and BS. CONCLUSION: Important clinical outcomes following FP BS and PBA for CLTI have not changed significantly in our unit in the 10 years following the BASIL-1 trial. BASIL-1 therefore remains relevant to our current practice and should inform our approach to the management of CLTI going forward.

Changes in health-related quality of life after ultrasound-guided foam sclerotherapy for great and small saphenous varicose veins.

BACKGROUND: Health-related quality of life (HRQOL) improves after superficial venous surgery for varicose veins, but the effect of ultrasound-guided foam sclerotherapy on HRQOL is unknown. The aim of this study was to determine changes in HRQOL after ultrasound-guided foam sclerotherapy for varicose veins. METHODS: Consecutive patients undergoing ultrasound-guided foam sclerotherapy for varicose veins were sent the Short Form 12 (SF-12) questionnaire, a generic measure of HRQOL, and the Aberdeen Varicose Vein Symptom Score (AVSS) questionnaire, a disease-specific measure of HRQOL, 1 week before treatment and 1, 6, and 12 months after treatment. RESULTS: The study enrolled 296 patients (34% male; 395 treated legs) with a median age of 57 years (range, 22-89 years). Of these, 24% had had previous superficial venous surgery, and 66% were CEAP C(2-3) (uncomplicated varicose veins). Questionnaire completion rates were 82%, 73%, and 69% at 1, 6, and 12 months after treatment. The median Physical Component Summary score of the SF-12 (higher score indicates better HRQOL) improved from 47.6 pretreatment to 49.4 at 1 month (P < .008, Wilcoxon signed rank test), to 51.9 at 6 months (P < .0005), and to 52.9 at 12 months (P < .0005). The median AVSS (lower score indicates better HRQOL) improved from 19.0 pretreatment to 16.5 at 1 month (P < .0005), to 8.7 at 6 months (P < .0005), and to 8.6 at 12 months (P < .0005). CONCLUSIONS: Ultrasound-guided foam sclerotherapy for great and small saphenous varicose veins leads to significant improvements in generic and disease-specific HRQOL for at least 12 months after treatment.

A reproducibility study of a TDI-based method to calculate indices of arterial stiffness.

The aim of the study was to investigate the reproducibility of estimation of Young's modulus E and pressure strain elastic modulus Ep, derived from a tissue Doppler imaging (TDI) wall motion technique. Healthy subjects had their arteries insonated at the same sitting by two different observers and at two different sittings by the same observer. From 32 subjects in the reproducibility study, within-scan coefficient of variation (CV) was 4.5%. Intraobserver between-scan CV for E was 12.7% and for Ep 11.0%. Interobserver CVs were 8.3% and 9.3%, respectively. TDI is a reproducible, valid and highly sensitive direct assessment of arterial wall parameters. It is at least as reproducible as other ultrasound based methods for assessing arterial stiffness and also provides increased information about the arterial distension waveform.