Illness Trajectories After Revascularization in Patients With Peripheral Artery Disease: A Unified Approach to Understanding the Risk of Major Amputation and Death.

BACKGROUND: The aim of this study was to investigate the illness trajectories of patients with peripheral artery disease (PAD) after revascularization and estimate the independent risks of major amputation and death (from any cause) and their interaction. METHODS: Data from Hospital Episode Statistics Admitted Patient Care were used to identify patients (≥50 years of age) who underwent lower limb revascularization for PAD in England from April 2013 to March 2020. A Markov illness-death model was developed to describe patterns of survival after the initial lower limb revascularization, if and when patients experienced major amputation, and survival after amputation. The model was also used to investigate the association between patient characteristics and these illness trajectories. We also analyzed the relative contribution of deaths after amputation to overall mortality and how the risk of mortality after amputation was related to the time from the index revascularization to amputation. RESULTS: The study analyzed 94 690 patients undergoing lower limb revascularization for PAD from 2013 to 2020. The majority were men (65.6%), and the median age was 72 years (interquartile range, 64-79). One-third (34.8%) of patients had nonelective revascularization, whereas others had elective procedures. For nonelective patients, the amputation rate was 15.2% (95% CI, 14.4-16.0) and 19.9% (19.0-20.8) at 1 and 5 years after revascularization, respectively. For elective patients, the corresponding amputation rate was 2.7% (95% CI, 2.4-3.1) and 5.3% (4.9-5.8). Overall, the risk of major amputation was higher among patients who were younger, had tissue loss, diabetes, greater frailty, nonelective revascularization, and more distal procedures. The mortality rate at 5 years after revascularization was 64.3% (95% CI, 63.2-65.5) for nonelective patients and 33.0% (32.0-34.1) for elective patients. After major amputation, patients were at an increased risk of mortality if they underwent major amputation within 6 months after the index revascularization. CONCLUSIONS: The illness-death model provides an integrated framework to understand patient outcomes after lower limb revascularization for PAD. Although mortality increased with age, the study highlights patients <60 years of age were at increased risk of major amputation, particularly after nonelective revascularization.

Editor's Choice - Vascular Registries Contributing to VASCUNET Collaborative Abdominal Aortic Aneurysm Outcome Projects: A Scoping Review.

OBJECTIVE: Vascular surgery registries report on procedures and outcomes to promote patient safety and drive quality improvement. International registries have contributed significantly to the VASCUNET collaborative abdominal aortic aneurysm (AAA) outcome projects. This scoping review aimed to outline the national registries in vascular surgery that currently participate in the VASCUNET collaborative AAA projects. METHODS: A scoping review of all published VASCUNET AAA studies and validation reports between 1997 and 2024 was undertaken. A survey was conducted among representatives of the international vascular registries contributing to VASCUNET collaborative AAA projects. RESULTS: Currently, vascular registries from 10 countries (Australia, Denmark, Finland, Hungary, Iceland, New Zealand, Norway, Sweden, Switzerland, and the UK) contribute to the current VASCUNET collaborative AAA project, of which eight have national coverage. In the past, three countries (Germany, Malta, and Italy) have participated in previous VASCUNET AAA projects, and a further three countries (Serbia, Greece, and Portugal) have planned participation in future projects. External validity is high for all current registries, with most reporting rates of > 90%. The majority have internal validation processes to assess data accuracy. VASCUNET mediated validation has also been performed by the consortium for five countries to date (Hungary, Sweden, Denmark, Malta, and Switzerland), for which a high degree of external and internal validity was identified. Most registries have established mechanisms for data linkage with national administrative datasets or insurance claims datasets and contribute to quality improvement through regular reporting to participating centres. CONCLUSION: National vascular registries from nations participating in the VASCUNET collaborative AAA projects are largely comprehensive, with high case ascertainment rates and good quality data with internal quality assurance. This provides a template for new registries wishing to join the VASCUNET collaboration and a benchmark for future research.

Editor's Choice - Outcomes Following Intact and Ruptured Aneurysm Repair across Nations: Analysis of International Registry Data from the VASCUNET Collaboration 2014 - 2019.

OBJECTIVE: To determine the peri-operative mortality rate for intact and ruptured abdominal aortic aneurysm (AAA) repair in 10 countries and to compare practice and outcomes over a six year period by age, sex, and geographic location. METHODS: This VASCUNET study used prospectively collected data from vascular registries in 10 countries on primary repair of intact and ruptured AAAs undertaken between January 2014 and December 2019. The primary outcome was peri-operative death (30 day or in hospital). Logistic regression models were used to estimate the association between peri-operative death, patient characteristics, and type of procedure. Factors associated with the use of endovascular aortic aneurysm repair (EVAR) were also evaluated. RESULTS: The analysis included 50 642 intact and 9 453 ruptured AAA repairs. The proportion of EVARs for intact repairs increased from 63.4% in 2014 to 67.3% in 2016 before falling to 62.3% in 2019 (p < .001), but practice varied between countries. EVAR procedures were more common among older patients (p < .001) and men (p < .001). Overall peri-operative mortality after intact AAA repair was 1.4% (95% confidence interval [CI] 1.3 - 1.5%) and did not change over time. Mortality rates were stable within countries. Among ruptured AAA repairs, the proportion of EVARs increased from 23.7% in 2014 to 35.2% in 2019 (p < .001). The average aortic diameter was 7.8 cm for men and 7.0 cm for women (p < .001). The overall peri-operative mortality rate was 31.3% (95% CI 30.4 - 32.2%); the rates were 36.0% (95% CI 34.9 - 37.2%) for open repair and 19.7% (95% CI 18.2 - 21.3%) for EVAR. This difference and shift to EVAR reduced peri-operative mortality from 32.6% (in 2014) to 28.7% (in 2019). CONCLUSION: The international practice of intact AAA repair was associated with low mortality rates in registry reported data. There remains variation in the use of EVAR for intact AAAs across countries. Overall peri-operative mortality remains high after ruptured AAA, but an increased use of EVAR has reduced rates over time.

Outcomes after minor lower limb amputation for peripheral arterial disease and diabetes: population-based cohort study.

BACKGROUND: Patients with diabetes and peripheral arterial disease are at increased risk of minor amputation. The aim of study was to assess the rate of re-amputations and death after an initial minor amputation, and to identify associated risk factors. METHODS: Data on all patients aged 40 years and over with diabetes and/or peripheral arterial disease, who underwent minor amputation between January 2014 and December 2018, were extracted from Hospital Episode Statistics. Patients who had bilateral index procedures or an amputation in the 3 years before the study were excluded. Primary outcomes were ipsilateral major amputation and death after the index minor amputation. Secondary outcomes were ipsilateral minor re-amputations, and contralateral minor and major amputations. RESULTS: In this study of 22 118 patients, 16 808 (76.0 per cent) were men and 18 473 (83.5 per cent) had diabetes. At 1 year after minor amputation, the estimated ipsilateral major amputation rate was 10.7 (95 per cent c.i. 10.3 to 11.1) per cent. Factors associated with a higher risk of ipsilateral major amputation included male sex, severe frailty, diagnosis of gangrene, emergency admission, foot amputation (compared with toe amputation), and previous or concurrent revascularization. The estimated mortality rate was 17.2 (16.7 to 17.7) per cent at 1 year and 49.4 (48.6 to 50.1) per cent at 5 years after minor amputation. Older age, severe frailty, comorbidity, gangrene, and emergency admission were associated with a significantly higher mortality risk. CONCLUSION: Minor amputations were associated with a high risk of major amputation and death. One in 10 patients had an ipsilateral major amputation within the first year after minor amputation and half had died by 5 years.

Editor's Choice - Outcomes of Surgery for Patients with Peripheral Arterial Disease During the COVID-19 Pandemic in the United Kingdom: A Population Based Study.

OBJECTIVE: There is limited information on changes in the patterns of care and outcomes for patients who had vascular procedures after the first wave of the COVID-19 pandemic. The aim of this population based study was to examine the patterns of care and outcomes for vascular lower limb procedures in the UK during the COVID-19 pandemic. METHODS: Lower limb revascularisations and major amputations performed from January 2019 to April 2021 in the UK and entered in the National Vascular Registry were included in the study. The primary outcome was in hospital post-operative death and secondary outcomes were complications and re-interventions. The study was divided into Pre-pandemic (1 January 2019 - 29 February 2020), Wave 1 (1 March - 30 June 2020), Respite (1 July - 31 October 2020), Wave 2/3 (1 November 2020 - 30 April 2021). RESULTS: The study included 36 938 procedures (7 245 major amputations, 16 712 endovascular, 12 981 open revascularisations), with 15 501 procedures after March 2020, a 27.7% reduction compared with pre-pandemic. The proportion of open surgical procedures performed under general anaesthetic was lower in Wave 1 and after compared with pre-pandemic (76.7% vs. 81.9%, p < .001). Only 4.6% of patients in the cohort had SARS-CoV-2 infection (n = 708), but their in hospital post-operative mortality rate was 25.0% (n = 177), six times higher than patients without SARS-CoV-2 (adjusted odds ratio 5.88; 95% CI 4.80 - 7.21, p < .001). The in hospital mortality rate was higher during the pandemic than pre-pandemic after elective open and endovascular revascularisation (respectively 1.6% vs. 1.1%, p = .033, and 0.9% vs. 0.5%, p = .005) and after major amputations (10.4% during Wave 2/3 vs. 7.7% pre-pandemic, p = .022). CONCLUSION: There was excess post-operative mortality rate for patients undergoing lower limb vascular procedures during the pandemic, which was associated with SARS-CoV-2 infections. Further research should be conducted on long term outcomes of patients operated on during the COVID-19 pandemic period.

The Impact of Pre-Operative Anaemia on One Year Amputation Free Survival and Re-Admissions in Patients Undergoing Vascular Surgery for Peripheral Arterial Disease: a National Vascular Registry Study.

OBJECTIVE: Anaemia is common among patients undergoing surgery, but its association with post-operative outcomes in patients with peripheral arterial disease (PAD) is unclear. The aim of this observational population based study was to examine the association between pre-operative anaemia and one year outcomes after surgical revascularisation for PAD. METHODS: This study used data from the National Vascular Registry, linked with an administrative database (Hospital Episode Statistics), to identify patients who underwent open surgical lower limb revascularisation for PAD in English NHS hospitals between January 2016 and December 2019. The primary outcome was one year amputation free survival. Secondary outcomes were one year re-admission rate, 30 day re-intervention rate, 30 day ipsilateral major amputation rate and 30 day death. Flexible parametric survival analysis and generalised linear regression were performed to assess the effect of anaemia on one year outcomes. RESULTS: The analysis included 13 641 patients, 57.9% of whom had no anaemia, 23.8% mild, and 18.3% moderate or severe anaemia. At one year follow up, 80.6% of patients were alive and amputation free. The risk of one year amputation or death was elevated in patients with mild anaemia (adjusted HR 1.3; 95% CI 1.15 - 1.41) and moderate or severe anaemia (aHR 1.5; 1.33 - 1.67). Patients with moderate or severe anaemia experienced more re-admissions over one year (adjusted IRR 1.31; 1.26 - 1.37) and had higher odds of 30 day re-interventions (aOR 1.22; 1.04 - 1.45), 30 day ipsilateral major amputation (aOR 1.53; 1.17 - 2.01), and 30 day death (aOR 1.39; 1.03 - 1.88) compared with patients with no anaemia. CONCLUSION: Pre-operative anaemia is associated with lower one year amputation free survival and higher one year re-admission rates following surgical revascularisation in patients with PAD. Research is required to evaluate whether interventions to correct anaemia improve outcomes after lower limb revascularisation.

Editor's Choice - The VASCUNExplanT Project: An International Study Assessing Open Surgical Conversion of Failed Non-Infected Endovascular Aortic Aneurysm Repair.

OBJECTIVE: The need for open surgical conversion (OSC) after failed endovascular aortic aneurysm repair (EVAR) persists, despite expanding endovascular options for secondary intervention. The VASCUNExplanT project collected international data to identify risk factors for failed EVAR, as well as OSC outcomes. This retrospective cross sectional study analysed data after OSC for failed EVAR from the VASCUNET international collaboration. METHODS: VASCUNET queried registries from its 28 member countries, and 17 collaborated with data from patients who underwent OSC (2005 - 2020). Any OSC for infection was excluded. Data included demographics, EVAR, and OSC procedural details, as well as post-operative mortality and complication rates. RESULTS: There were 348 OSC patients from 17 centres, of whom 33 (9.4%) were women. There were 130 (37.4%) devices originally deployed outside of instructions for use. The most common indication for OSC was endoleak (n = 143, 41.1%); ruptures accounted for 17.2% of cases. The median time from EVAR to OSC was 48.6 months [IQR 29.7, 71.6]; median abdominal aortic aneurysm diameter at OSC was 70.5 mm [IQR 61, 82]. A total of 160 (45.6%) patients underwent one or more re-interventions prior to OSC, while 63 patients (18.1%) underwent more than one re-intervention (range 1 - 5). Overall, the 30 day mortality rate post-OSC was 11.8% (n = 41), 11.1% for men and 18.2% for women (p = .23). The 30 day mortality rate was 6.1% for elective cases, and 28.3% for ruptures (p < .0001). The predicted 90 day survival for the entire cohort was 88.3% (95% CI 84.3 - 91.3). Multivariable analysis revealed rupture (OR 4.23; 95% CI 2.05 - 8.75; p < .0001) and total graft explantation (OR 2.10; 95% CI 1.02 - 4.34; p = .04) as the only statistically significant predictive factors for 30 day death. CONCLUSION: This multicentre analysis of patients who underwent OSC shows that, despite varying case mix and operative techniques, OSC is feasible but associated with significant morbidity and mortality rates, particularly when performed for rupture.

Delays to revascularization for patients with chronic limb-threatening ischaemia.

BACKGROUND: Vascular services in England are organized into regional hub-and-spoke models, with hubs performing arterial surgery. This study examined time to revascularization for chronic limb-threatening ischaemia (CLTI) within and across different care pathways, and its association with postrevascularization outcomes. METHODS: Three inpatient and four outpatient care pathways were identified for patients with CLTI undergoing revascularization between April 2015 and March 2019 using Hospital Episode Statistics data. Differences in times from presentation to revascularization across care pathways were analysed using Cox regression. The relationship between postoperative outcomes and time to revascularization was evaluated by logistic regression. RESULTS: Among 16 483 patients with CLTI, 9470 had pathways starting with admission to a hub or spoke hospital, whereas 7013 (42.5 per cent) were first seen at outpatient visits. Among the inpatient pathways, patients admitted to arterial hubs had shorter times to revascularization than those admitted to spoke hospitals (median 5 (i.q.r. 2-10) versus 12 (7-19) days; P < 0.001). Shorter times to revascularization were also observed for patients presenting to outpatient clinics at arterial hubs compared with spoke hospitals (13 (6-25) versus 26 (15-35) days; P < 0.001). Within most care pathways, longer delays to revascularizsation were associated with increased risks of postoperative major amputation and in-hospital death, but the effect of delay differed across pathways. CONCLUSION: For patients with CLTI, time to revascularization was influenced by presentation to an arterial hub or spoke hospital. Generally, longer delays to revascularization were associated with worse outcomes, but the impact of delay differed across pathways.

Outcomes in Men From the NHS Abdominal Aortic Aneurysm Screening Programme With a Large Aneurysm Referred for Intervention.

OBJECTIVE: The NHS Abdominal Aortic Aneurysm Screening Programme (NAAASP) has been implemented since 2013. Men with a large aneurysm >54 mm, either at first screen or during surveillance, are referred for intervention. The aim of the present study was to explore outcomes in these men and to see whether there was any regional variation in treatment rates and type of repair. METHODS: The study cohort included all men referred to a vascular network with a large abdominal aortic aneurysm (AAA). Basic demographic information, nurse assessment details, as well as outcome data were extracted from the national NAAASP IT system, AAA SMaRT, for analysis. RESULTS: Some 3 026 men were referred for possible intervention (48% first screen, 52% surveillance). Some 448 men (13.3%) either declined (63, 2.1%), or were turned down for early intervention for various reasons (385, 12.7%). Some 8% were declined for medical reasons (true turn down rate). Men referred from surveillance were older, and more likely not to have had elective surgery within three months (16.0 vs. 11.2%; HR 1.37, 95% CI 1.07-1.75, p = .011). Turn down rates did not vary among local programmes, when surveillance men were taken into account. Some 2 624 (87%) men had planned AAA repair, with a peri-operative mortality of 1.3%. Thirty day surgical mortality was lower after EVAR: 0.4% compared with 2.1% after open repair. The method of repair remained consistent year on year, with roughly equal numbers undergoing endovascular (50%) and open surgical repair (48%); 2% unknown. There was regional variation in the proportion treated by endovascular repair: from 20% to 97%. CONCLUSION: The turn down rate after referral for treatment with a screen detected AAA was low, but there remains considerable regional variation in the proportion undergoing endovascular repair. Procedures were undertaken with low peri-operative mortality.

Carotid Endarterectomy Following Intravenous Thrombolysis in the UK.

OBJECTIVE: The aim of this study was to evaluate the effect of pre-operative intravenous thrombolytic therapy (ivTT) on short term outcomes after carotid endarterectomy (CEA) among patients who presented with ischaemic stroke. METHODS: A retrospective study using a large population based dataset from the National Vascular Registry in the United Kingdom (UK-NVR). The cohort included adult patients who underwent CEA for ischaemic stroke between 1 January 2014 and 31 December 2019. NVR records provided information on patient demographics, Rankin score, medication, time from onset of symptoms to surgery and whether the patient received ivTT prior to surgery. Logistic regression was used to evaluate the relationship between ivTT and rates of any stroke at 30 days after CEA and in hospital complication rates for neck haematoma. Secondary outcomes included in hospital cardiac and respiratory complications, and cranial nerve injury. RESULTS: Between 2014 and 2019, 9 030 patients presented with a stroke and underwent CEA, of whom 1 055 (11.7%) had received pre-operative ivTT. Those receiving ivTT were younger (mean 70.6 vs. 72.0 years, p < .001). The median (IQR) time from symptom to CEA was 10 days (6 - 17) for ivTT patients and 11 days (7 - 20) for CEA patients not receiving ivTT. Post-operative rates of 30 day stroke were similar between the no ivTT (2.1%) and ivTT (1.8%) cohorts (p = .48). In hospital neck haematomas were statistically significantly more common in CEA patients receiving ivTT (3.7%) vs. no ivTT (2.3%) (p = .006). There was no statistically significant association between 30 day stroke and neck haematoma complications when stratified for delays from symptom onset to CEA, but the overall cohort contained few adverse events for analysis during the very early time period. CONCLUSION: The use of ivTT before CEA in stroke patients was not associated with an increased risk of 30 day stroke, but there was an increase in the risk of neck haematoma.

Blunt Thoracic Aortic Injury and Acute Trauma: The Effect on Aortic Diameter and the Consequences for Stent-graft Sizing.

BACKGROUND: Blunt thoracic aortic injury (BTAI) is associated with a high mortality and large trauma burden. Trauma and resuscitation after injury affect cardiovascular status, which may in turn affect aortic diameter. Measurement of aortic diameter is necessary to guide stent-graft sizing as part of BTAI management. Inaccurate measurement may lead to stent-graft complications. This pilot study aimed to assess the effect of acute major trauma on stent-graft sizing and stent-graft complications, in the context of BTAI and to assess whether any effect could be predicted. METHODS: Patients who were admitted to a UK major trauma center between January 2007 and December 2017, and were diagnosed with BTAI, were identified. The thoracic aortic diameter was measured at six points on initial and surveillance computed tomography imaging. Data on patient demographics, admission heart rate, mean arterial pressure (MAP), and serum lactate were gathered. RESULTS: Thirty-two patients were identified. Twenty met inclusion criteria. Of these, 12 were managed operatively and eight nonoperatively. The mean age was 40, the mean injury severity score was 43, and 85% were male. A mean increase in diameter between initial trauma scan and surveillance scan was noted throughout the thoracic aorta (P < 0.05). Stent-graft oversizing relative to aortic diameter changed significantly from initial trauma imaging to surveillance imaging (P < 0.05). Admission heart rate, MAP, and serum lactate were not predictive of the percentage change in aortic diameter. There were no complications at surveillance imaging (mean 45 days) or during medium term follow-up (mean 532 days). CONCLUSIONS: Aortic diameter is affected by BTAI, acute major trauma, and resuscitation in a significant and variable manner. Measurements of the aorta in a patient with BTAI in the acute trauma setting should be viewed with uncertainty. A lack of complications in the short term is suggestive of a wide tolerance range regarding stent-graft sizing, but long-term results are unknown.

Early and Late Outcomes of Surgery for Neurogenic Thoracic Outlet Syndrome in Adolescents.

BACKGROUND: Neurogenic thoracic outlet syndrome is a condition that is both complex to diagnose and manage successfully. The aim of our study was to present our experience and outcomes of surgical management of thoracic outlet syndrome in adolescents. METHODS: We performed a retrospective analysis of a prospectively held database of consecutive adolescents (age 10-19 years) who underwent surgery for neurogenic thoracic outlet syndrome between 2005 and 2017 at our university hospital. RESULTS: Fourteen patients were identified (19 operations), with a mean age of 16.5 years (SD: 1.9). All patients had symptomatic relief with surgery with low complication rates (1 pneumothorax). Median hospital stay was 2 days (IQR: 1). There were no early recurrences but 5 late ones which occurred 2, 2.5, 3, 4 and 10 years after surgery (20%). None required a second procedure and were managed successfully with physiotherapy. CONCLUSIONS: Surgical intervention for thoracic outlet syndrome in the adolescent population results in excellent outcomes in the short term. However, we found that recurrence of symptoms in this population is common and patients need to be counseled clearly about this prior to surgical intervention. However in our experience these do not require further surgery.

Impact of Frailty on Outcomes in Patients Undergoing Open Abdominal Aortic Aneurysm Repair.

BACKGROUND: Frailty is a global state that does not relate directly to comorbidities and is prevalent among patients with vascular disease. The Clinical Frailty Scale (CFS) is a rapid assessment tool to identify vulnerable and frail patients. In this study, we sought to evaluate whether the preoperative CFS score could be used to independently predict mortality and morbidity after elective open abdominal aortic aneurysm (AAA) repair. METHODS: We retrospectively reviewed our institutional National Vascular Registry (NVR) data to identify all patients who underwent an elective open juxta or infrarenal AAA repair between January 2014 and December 2018. The NVR data set included preoperative risk factors, imaging findings, intraprocedural variables, and postprocedural outcomes. RESULTS: A total of 184 patients were assessed using the CFS before they underwent elective open AAA repair. Among 26 (14%) individuals categorized as vulnerable using the CFS, there was no significant difference in age or preoperative cardiac and respiratory testing compared with nonfrail patients. However, vulnerable patients were significantly more likely to have a longer length of stay (12.2 days vs. 8.8 days, P-value 0.044), suffer from respiratory complications (35% vs. 15%, P-value 0.022) and renal failure (23% vs. 6%, P-value 0.013), or die (23% vs. 2%, P-value 0.0003). The regression analysis identified a vulnerable frailty score to be the only significant predictor of mortality (odds ratio = 36.7, P < 0.001), all other factors were not shown to be independent predictors. CONCLUSIONS: The CFS is a practical tool for assessing preoperative frailty among patients undergoing elective open AAA repair and can be used to predict mortality and morbidity after surgery.

The Transposed Femoral Vein Fistula: The Native Choice in Desperate Vascular Access.

BACKGROUND: This is a review of our experience in creating transposed femoral vein (TFV) fistulas and some of the lessons we have learnt while performing this challenging procedure over the last 5 years. METHODS: This is retrospective review of patients who underwent TFV fistula formation between January 2013 and December 2017. RESULTS: Fifteen patients underwent FV fistula formation with 4 cases being excluded from analysis. Median follow-up was 1.17 years (interquartile range 0.19-3.59 years). Primary and primary-assisted patency rates were 75% and 100% at 6 months, respectively, and 66.7% and 100% at 1 year. CONCLUSIONS: Our patient group showed good fistula patency at 1 year and did not experience any incidence of ischemic steal syndrome. We believe this to be due to careful preoperative patient assessment and meticulous surgical technique. Our experience suggests that such procedures should be performed by surgeons with vascular expertise wherever possible to reduce the incidence of complications.

Screening for Abdominal Aortic Aneurysm During Transthoracic Echocardiography: A Systematic Review and Meta-analysis.

BACKGROUND: Screening for abdominal aortic aneurysm (AAA) during transthoracic echocardiography (TTE) may be an effective targeted screening strategy. OBJECTIVE: The aim was to assess the feasibility of AAA screening during TTE and to estimate the prevalence of AAA in patients undergoing TTE. METHODS: Electronic bibliographic sources were interrogated using a combination of free text and controlled vocabulary searches to identify studies reporting on AAA screening during TTE. The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement standards. Fixed effect or random effects models were used to calculate pooled prevalence estimates. RESULTS: Twenty observational cohort studies were identified reporting a total of 43,341 participants (23,291 men and 20,050 women). Hypertension was reported in 41% (95% CI 38-43), hypercholesterolemia in 31% (95% CI 29-32), diabetes mellitus in 20% (95% CI 19-22), and tobacco use in 37% (95% CI 35-38). The aorta was visualised in 86% (95% CI 84-88) of the screened population. The pooled prevalence of AAA in the entire screened population was 0.033 (95% CI 0.024-0.044). The pooled prevalence of AAA in men was 0.046 (95% CI 0.032-0.065) and in women it was 0.014 (95% CI 0.008-0.022). The mean age of participants in whom an AAA was detected ranged across the studies from 66 to 85 years. The mean diameter of the aneurysm identified ranged across the studies from 35 mm to 45 mm. Clinical outcomes in participants with a detected AAA were poorly reported. CONCLUSIONS: Screening for AAA during TTE may identify a population group with a high risk of AAA in whom targeted screening may be beneficial. Further research is required to investigate the cost-effectiveness and clinical benefits of AAA screening in this setting.

Role of compression therapy in pathophysiology of the venous system in lower limbs.

The management of varicose veins and their sequelae are estimated to cost the NHS approximately £400-600 m annually. Along with interventional procedures, the National Institute for Health and Care Excellence (NICE) also recommends the use of compression therapy. With the vast array of different compression therapies available, prescribing the correct method can be challenging, with patients receiving incorrect compression being a matter of concern. This review summarises the key principles underpinning the management of these patients with particular emphasis on the pathophysiology and different classes of compression.

Simultaneous Iliac Vein Bovine Pericardial Patch Venoplasty and Creation of PTFE Lower Limb Arteriovenous Fistula Graft for Rescue Vascular Access.

BACKGROUND: We present a case of external iliac vein patch venoplasty to accommodate rescue vascular access via a polytetrafluoroethylene loop arteriovenous fistula graft (AVG) for a patient with multiple central venous stenoses. METHODS: A 35-year-old female with anti-glomerular basement membrane antibody disease required rescue vascular access for hemodialysis. Repeated occlusion and/or thrombosis of long-term central venous access cannulae, to facilitate dialysis, had caused stenosis of brachiocephalic veins: right external iliac vein and occlusion of the left common iliac vein. A previous right brachiobasilic fistula had occluded within 1 year. No other upper limb options for arteriovenous fistula (AVF) were available. A right external iliac vein bovine patch angioplasty concurrently with a polytetrafluoroethylene AV graft between common femoral artery and common femoral vein was performed to restore venous patency and allow rescue dialysis access. RESULTS: At 3-year follow-up, the fistula remains widely patent with 2 L/min flow rates and no recurrent stenosis to the treated iliac vein. She has not required any further surgical or interventional radiological procedures to maintain fistula or central venous patency. Central venous stenosis or occlusion is common for patients requiring dialysis, especially those with multiple previous long-term central venous cannulations. If restriction of outflow is present, AVF may fail. Venous patch angioplasty in these cases is a successful technique, allowing AVF formation and long-term patency. CONCLUSION: Central venous stenosis can be treated successfully with patch venoplasty to accommodate AVF/AVG formation for rescue vascular access; this is a potentially lifesaving intervention for patients requiring dialysis.