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Objective The aim was to understand why two recently published guidelines for the diagnosis and management of patients with abdominal aortic aneurysm, the National Institute for Health and Care Excellence (NICE) 2020 guidelines and the European Society for Vascular Surgery (ESVS) 2019 guidelines, have discordant recommendations in several important areas. Methods A review of the approach, methodology, and evidence used by the two guideline committees was carried out to understand potential reasons for their differing recommendations in their two final published guidelines. Results NICE guidelines use a multidisciplinary committee to address a limited number of prospectively identified questions, using rigorous methods heavily reliant on evidence from randomised controlled trials (RCTs) supported by in house economic modelling, with the purpose of providing the best, cost-effective health care in the UK in 46 main recommendations. The ESVS guidelines use an expert committee to encourage clinical effectiveness across a range of European health economies. ESVS guideline topics, but not questions, are prospectively identified, assessment of evidence was less rigorous, and 125 recommendations were made. More up to date evidence searches by the ESVS committee partially underscore the differences in recommendations for screening women. The NICE committee did not consider sex specific analysis or evidence for thresholds for intervention but relied on sex specific modelling to support their advice to use endovascular repair (EVAR) for ruptures in women. Their recommendation to use open repair for ruptured abdominal aortic aneurysms (AAAs) in men aged < 71 years was based on in house economic modelling. NICE recommends an open first strategy for non-ruptured AAA mainly based on earlier RCTs and UK specific economic modelling, while the ESVS guidelines recommend an EVAR first strategy after consideration of modern, but lower quality, evidence from observational studies. Similar reasons explain differences in the recommended treatments of juxtarenal aneurysms. Conclusion Differences between the NICE and ESVS guidelines can be explained, at least in part, by their differing perspectives, methodologies, and quality assurance. Future ESVS guidelines may benefit from more multidisciplinary input and prospectively identified questions.

Markov models are often used to evaluate the cost-effectiveness of new healthcare interventions but they are sometimes not flexible enough to allow accurate modeling or investigation of alternative scenarios and policies. A Markov model previously demonstrated that a one-off invitation to screening for abdominal aortic aneurysm (AAA) for men aged 65 y in the UK and subsequent follow-up of identified AAAs was likely to be highly cost-effective at thresholds commonly adopted in the UK (£20,000 to £30,000 per quality adjusted life-year). However, new evidence has emerged and the decision problem has evolved to include exploration of the circumstances under which AAA screening may be cost-effective, which the Markov model is not easily able to address. A new model to handle this more complex decision problem was needed, and the case of AAA screening thus provides an illustration of the relative merits of Markov models and discrete event simulation (DES) models. An individual-level DES model was built using the R programming language to reflect possible events and pathways of individuals invited to screening v. those not invited. The model was validated against key events and cost-effectiveness, as observed in a large, randomized trial. Different screening protocol scenarios were investigated to demonstrate the flexibility of the DES. The case of AAA screening highlights the benefits of DES, particularly in the context of screening studies.

Objective: The aim of the study was to compare long-term total and aneurysm-related mortality in physically frail patients with abdominal aortic aneurysm (AAA) randomized to either early endovascular aneurysm repair (EVAR) or no-intervention. Summary Background Data: EVAR-2 remains the sole randomized trial to identify whether EVAR reduces mortality in patients physically ineligible for open repair. Methods: Between September 1999 and August 2004, 404 patients from 33 centers in the United Kingdom aged ≥60 years with AAA >5.5 cm in diameter were randomized 1:1 using computer-generated sequences of randomly permuted blocks stratified by center to receive either EVAR (197) or no-intervention (207). The primary analysis compared total and aneurysm-related deaths in groups until June 30, 2015 (mean, 12.0 yrs; maximum 14.1 yrs). Results: Mean follow-up until death or censoring was 4.2 years. There were 187 deaths (22.6 per 100 person-yrs) in the EVAR group and 194 (22.1 per 100 person-yrs) in the no-intervention group. By 12 years of follow-up the estimated survival was 5.3% [95% confidence interval (CI), 2.6–9.2] in the EVAR group and 8.5% (95% CI, 5.2–12.9) in the no-intervention group; there was no significant difference in life expectancy between the groups (both 4.2 yrs; P = 0.97). However, overall aneurysm-related mortality was significantly lower in the EVAR group [3.3 deaths per 100 person-yrs compared with 6.5 deaths per 100 person-yrs in the no-intervention group, adjusted hazard ratio 0.55 (95% CI, 0.34–0.91; P = 0.019)]. Patients surviving beyond 8 years were younger, with higher body mass index, estimated glomerular filtration rate, and forced expiratory volume in 1 second. Conclusions: EVAR does not increase overall life expectancy in patients ineligible for open repair, but can reduce aneurysm-related mortality.

Background: Ruptured abdominal aortic aneurysm is a common vascular emergency. The mortality from emergency endovascular repair may be much lower than the 40-50% reported for open surgery. Objectives: To assess whether a strategy of endovascular repair versus open repair reduces 30-day and mid-term mortality (costs and cost-effectiveness) for patients with suspected ruptured abdominal aortic aneurysm. Design: Randomised controlled trial, with computer-generated telephone randomisation of patients in a 1:1 ratio, using variable block size, stratified by centre, without blinding

BACKGROUND: The aim of this study was to develop a 48-h mortality risk score, which included morphology data, for patients with ruptured abdominal aortic aneurysm presenting to an emergency department, and to assess its predictive accuracy and clinical effectiveness in triaging patients to immediate aneurysm repair, transfer or palliative care. METHODS: Data from patients in the IMPROVE (Immediate Management of the Patient With Ruptured Aneurysm: Open Versus Endovascular Repair) randomized trial were used to develop the risk score. Variables considered included age, sex, haemodynamic markers and aortic morphology. Backwards selection was used to identify relevant predictors. Predictive performance was assessed using calibration plots and the C-statistic. Validation of the newly developed and other previously published scores was conducted in four external populations. The net benefit of treating patients based on a risk threshold compared with treating none was quantified. RESULTS: Data from 536 patients in the IMPROVE trial were included. The final variables retained were age, sex, haemoglobin level, serum creatinine level, systolic BP, aortic neck length and angle, and acute myocardial ischaemia. The discrimination of the score for 48-h mortality in the IMPROVE data was reasonable (C-statistic 0·710, 95 per cent c.i. 0·659 to 0·760), but varied in external populations (from 0·652 to 0·761). The new score outperformed other published risk scores in some, but not all, populations. An 8 (95 per cent c.i. 5 to 11) per cent improvement in the C-statistic was estimated compared with using age alone. CONCLUSION: The assessed risk scores did not have sufficient accuracy to enable potentially life-saving decisions to be made regarding intervention. Focus should therefore shift to offering repair to more patients and reducing non-intervention rates, while respecting the wishes of the patient and family.

OBJECTIVE/BACKGROUND: The aim was to describe the re-interventions after endovascular and open repair of rupture, and investigate whether these were associated with aortic morphology. METHODS: In total, 502 patients from the IMPROVE randomised trial (ISRCTN48334791) with repair of rupture were followed-up for re-interventions for at least 3 years. Pre-operative aortic morphology was assessed in a core laboratory. Re-interventions were described by time (0-90 days, 3 months-3 years) as arterial or laparotomy related, respectively, and ranked for severity by surgeons and patients separately. Rare re-interventions to 1 year, were summarised across three ruptured abdominal aortic aneurysm trials (IMPROVE, AJAX, and ECAR) and odds ratios (OR) describing differences were pooled via meta-analysis. RESULTS: Re-interventions were most common in the first 90 days. Overall rates were 186 and 226 per 100 person years for the endovascular strategy and open repair groups, respectively (p = .20) but between 3 months and 3 years (mid-term) the rates had slowed to 9.5 and 6.0 re-interventions per 100 person years, respectively (p = .090) and about one third of these were for a life threatening condition. In this latter, mid-term period, 42 of 313 remaining patients (13%) required at least one re-intervention, most commonly for endoleak or other endograft complication after treatment by endovascular aneurysm repair (EVAR) (21 of 38 re-interventions), whereas distal aneurysms were the commonest reason (four of 23) for re-interventions after treatment by open repair. Arterial re-interventions within 3 years were associated with increasing common iliac artery diameter (OR 1.48, 95% confidence interval [CI] 0.13-0.93; p = .004). Amputation, rare but ranked as the worst re-intervention by patients, was less common in the first year after treatment with EVAR (OR 0.2, 95% CI 0.05-0.88) from meta-analysis of three trials. CONCLUSION: The rate of mid-term re-interventions after rupture is high, more than double that after elective EVAR and open repair, suggesting the need for bespoke surveillance protocols. Amputations are much less common in patients treated by EVAR than in those treated by open repair.

Importance: Risk factors for abdominal aortic aneurysm (AAA) are largely unknown, which has hampered the development of nonsurgical treatments to alter the natural history of disease. Objective: To investigate the association between lipid-associated single-nucleotide polymorphisms (SNPs) and AAA risk. Design, Setting, and Participants: Genetic risk scores, composed of lipid trait–associated SNPs, were constructed and tested for their association with AAA using conventional (inverse-variance weighted) mendelian randomization (MR) and data from international AAA genome-wide association studies. Sensitivity analyses to account for potential genetic pleiotropy included MR-Egger and weighted median MR, and multivariable MR method was used to test the independent association of lipids with AAA risk. The association between AAA and SNPs in loci that can act as proxies for drug targets was also assessed. Data collection took place between January 9, 2015, and January 4, 2016. Data analysis was conducted between January 4, 2015, and December 31, 2016. Exposures: Genetic elevation of low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides (TG). Main Outcomes and Measures: The association between genetic risk scores of lipid-associated SNPs and AAA risk, as well as the association between SNPs in lipid drug targets (HMGCR, CETP, and PCSK9) and AAA risk. Results: Up to 4914 cases and 48 002 controls were included in our analysis. A 1-SD genetic elevation of LDL-C was associated with increased AAA risk (odds ratio [OR], 1.66; 95% CI, 1.41-1.96; P = 1.1 × 10−9). For HDL-C, a 1-SD increase was associated with reduced AAA risk (OR, 0.67; 95% CI, 0.55-0.82; P = 8.3 × 10−5), whereas a 1-SD increase in triglycerides was associated with increased AAA risk (OR, 1.69; 95% CI, 1.38-2.07; P = 5.2 × 10−7). In multivariable MR analysis and both MR-Egger and weighted median MR methods, the association of each lipid fraction with AAA risk remained largely unchanged. The LDL-C–reducing allele of rs12916 in HMGCR was associated with AAA risk (OR, 0.93; 95% CI, 0.89-0.98; P = .009). The HDL-C–raising allele of rs3764261 in CETP was associated with lower AAA risk (OR, 0.89; 95% CI, 0.85-0.94; P = 3.7 × 10−7). Finally, the LDL-C–lowering allele of rs11206510 in PCSK9 was weakly associated with a lower AAA risk (OR, 0.94; 95% CI, 0.88-1.00; P = .04), but a second independent LDL-C–lowering variant in PCSK9 (rs2479409) was not associated with AAA risk (OR, 0.97; 95% CI, 0.92-1.02; P = .28). Conclusions and Relevance: The MR analyses in this study lend support to the hypothesis that lipids play an important role in the etiology of AAA. Analyses of individual genetic variants used as proxies for drug targets support LDL-C lowering as a potential effective treatment strategy for preventing and managing AAA.

BACKGROUND: Although women represent an increasing proportion of those presenting with abdominal aortic aneurysm (AAA) rupture, the current prevalence of AAA in women is unknown. The contemporary population prevalence of screen-detected AAA in women was investigated by both age and smoking status. METHODS: A systematic review was undertaken of studies screening for AAA, including over 1000 women, aged at least 60 years, done since the year 2000. Studies were identified by searching MEDLINE, Embase and CENTRAL databases until 13 January 2016. Study quality was assessed using the Newcastle-Ottawa scoring system. RESULTS: Eight studies were identified, including only three based on population registers. The largest studies were based on self-purchase of screening. Altogether 1 537 633 women were screened. Overall AAA prevalence rates were very heterogeneous, ranging from 0·37 to 1·53 per cent: pooled prevalence 0·74 (95 per cent c.i. 0·53 to 1·03) per cent. The pooled prevalence increased with both age (more than 1 per cent for women aged over 70 years) and smoking (more than 1 per cent for ever smokers and over 2 per cent in current smokers). CONCLUSION: The current population prevalence of screen-detected AAA in older women is subject to wide demographic variation. However, in ever smokers and those over 70 years of age, the prevalence is over 1 per cent.

Objective To assess the three year clinical outcomes and cost effectiveness of a strategy of endovascular repair (if aortic morphology is suitable, open repair if not) versus open repair for patients with suspected ruptured abdominal aortic aneurysm. Design Randomised controlled trial. Setting 30 vascular centres (29 in UK, one in Canada), 2009-16. Participants 613 eligible patients (480 men) with a clinical diagnosis of ruptured aneurysm, of whom 502 underwent emergency repair for rupture. Interventions 316 patients were randomised to an endovascular strategy (275 with confirmed rupture) and 297 to open repair (261 with confirmed rupture). Main outcome measures Mortality, with reinterventions after aneurysm repair, quality of life, and hospital costs to three years as secondary measures. Results The maximum follow-up for mortality was 7.1 years, with two patients in each group lost to follow-up by three years. After similar mortality by 90 days, in the mid-term (three months to three years) there were fewer deaths in the endovascular than the open repair group (hazard ratio 0.57, 95% confidence interval 0.36 to 0.90), leading to lower mortality at three years (48% v 56%), but by seven years mortality was about 60% in each group (hazard ratio 0.92, 0.75 to 1.13). Results for the 502 patients with repaired ruptures were more pronounced: three year mortality was lower in the endovascular strategy group (42% v 54%; odds ratio 0.62, 0.43 to 0.88), but after seven years there was no clear difference between the groups (hazard ratio 0.86, 0.68 to 1.08). Reintervention rates up to three years were not significantly different between the randomised groups (hazard ratio 1.02, 0.79 to 1.32); the initial rapid rate of reinterventions was followed by a much slower mid-term reintervention rate in both groups. The early higher average quality of life in the endovascular strategy versus open repair group, coupled with the lower mortality at three years, led to a gain in average quality adjusted life years (QALYs) at three years of 0.17 (95% confidence interval 0.00 to 0.33). The endovascular strategy group spent fewer days in hospital and had lower average costs of −£2605 (95% confidence interval −£5966 to £702) (about €2813; $3439). The probability that the endovascular strategy is cost effective was >90% at all levels of willingness to pay for a QALY gain. Conclusions At three years, compared with open repair, an endovascular strategy for suspected ruptured abdominal aortic aneurysm was associated with a survival advantage, a gain in QALYs, similar levels of reintervention, and reduced costs, and this strategy was cost effective. These findings support the increasing use of an endovascular strategy, with wider availability of emergency endovascular repair. Trial registration Current Controlled Trials ISRCTN48334791; ClinicalTrials NCT00746122.

Background Prognosis for women with abdominal aortic aneurysm might be worse than the prognosis for men. We aimed to systematically quantify the differences in outcomes between men and women being assessed for repair of intact abdominal aortic aneurysm using data from study periods after the year 2000. Methods In these systematic reviews and meta-analysis, we identified studies (randomised, cohort, or cross-sectional) by searching MEDLINE, Embase, CENTRAL, and grey literature published between Jan 1, 2005, and Sept 2, 2016, for two systematic reviews and Jan 1, 2009, and Sept 2, 2016, for one systematic review. Studies were included if they were of both men and women, with data presented for each sex separately, with abdominal aortic aneurysms being assessed for aneurysm repair by either endovascular repair (EVAR) or open repair. We conducted three reviews based on whether studies reported the proportion morphologically suitable (within manufacturers' instructions for use) for EVAR (EVAR suitability review), non-intervention rates (non-intervention review), and 30-day mortality (operative mortality review) after intact aneurysm repair. Studies had to include at least 20 women (for the EVAR suitability review), 20 women (for the non-intervention review), and 50 women (for the operative mortality review). Studies were excluded if they were review articles, editorials, letters, or case reports. For the operative review, studies were also excluded if they only provided hazard ratios or only reported in-hospital mortality. We assessed the quality of the studies using the Newcastle–Ottawa scoring system, and contacted authors for the provision of additional data if needed. We combined results across studies by random-effects meta-analysis. This study is registered with PROSPERO, number CRD42016043227. Findings Five studies assessed the morphological eligibility for EVAR (1507 men, 400 women). The overall pooled proportion of women eligible (34%) for EVAR was lower than it was in men (54%; odds ratio [OR] 0·44, 95% CI 0·32–0·62). Four single-centre studies reported non-intervention rates (1365 men, 247 women). The overall pooled non-intervention rates were higher in women (34%) than men (19%; OR 2·27, 95% CI 1·21–4·23). The review of 30-day mortality included nine studies (52 018 men, 11 076 women). The overall pooled estimate for EVAR was higher in women (2·3%) than in men (1·4%; OR 1·67, 95% CI 1·38–2·04). The overall estimate for open repair also was higher in women (5·4%) than in men (2·8%; OR 1·76, 95% CI 1·35–2·30). Interpretation Compared with men, a smaller proportion of women are eligible for EVAR, a higher proportion of women are not offered intervention, and operative mortality is much higher in women for both EVAR and open repair. The management of abdominal aortic aneurysm in women needs improvement.

Objective: To systematically quantify the differences in outcomes between men and women being assessed for repair of intact abdominal aortic aneurysm (AAA) in contemporary data (2000 or later). Methods: Three systematic reviews were undertaken, according to PRISMA guidelines of studies reporting separately for men and women the proportion morphologically suitable (within Manufacturers’ Instructions for Use) for endovascular repair (EVAR), non-intervention rates, and 30-day mortality after intact aneurysm repair. The minimum numbers for studies in each review were based on inclusion of 20, 20 and 50 women, respectively. Studies (randomised, cohort or cross-sectional) were identified by searching MEDLINE, Embase, CENTRAL and other sources until 2nd September 2016 and quality assessed using the Newcastle–Ottawa scoring system. Results were combined across studies by random-effects meta-analysis. The reviews are registered in PROSPERO: CRD42016043227. Results: Five studies evaluated the morphological eligibility for EVAR (1507 men, 400 women). The overall proportion of women eligible for EVAR was much lower than in men, 34% versus 54%, odds ratio 0.44 [95%CI 0.32,0.62]. Four single centre studies reported non-intervention rates (1365 men, 247 women). The overall non-intervention rates were higher in women than men, 34% versus 19%, odds ratio 2.27 [95%CI 1.21,4.23]. The review of 30-day mortality included nine studies (52018 men, 10076 women). The overall estimate for EVAR was higher in women than men: 2.3% versus 1.4%, odds ratio 1.67 [95%CI 1.38,2.04]. The overall estimate for open repair also was higher in women: 5.4% versus 2.8% in men, odds ratio 1.76 [95%CI 1.35,2.30]. Interpretation: A smaller proportion of women are eligible for EVAR, a higher proportion of women are not offered intervention, and operative mortality was much higher in women for both EVAR and open repair. The management of AAA in women needs improvement.

Platelet derived growth factor BB (PDGF BB) has an important influence on smooth muscle cell migration and proliferation in restenosis and atherosclerosis. Our understanding of different signal transduction pathways involved in the response of smooth muscle cells to PDGF BB is potentially significant for understanding and manipulating these processes. Prior studies have demonstrated a crucial activation of cytosolic phospholipase A2 (cPLA2) in smooth muscle cells to PDGF BB with the production of arachidonic acid and prostaglandin E2. In this study, we first investigated the role of cPLA2α on human aortic smooth muscle cell (HASMC) migration using modified Boyden chamber assay and under agarose migration studies. AACOCF3 (cPLA2 and iPLA2 inhibitor), 1,2,4-trisubstituted pyrrolidine derivative (cPLA2 inhibitor), and Bromoenol lactone (iPLA2 inhibitor) had no effect on HASMC chemotaxis to PDGF-BB in a modified Boyden chamber. These results were confirmed with specific inhibition of cPLA2α using small interfering RNA (siRNA) showing that HASMC migration was not inhibited in modified Boyden chamber or under agarose migration studies. Using the same siRNA to cPLA2 alpha had very significant inhibition to PDGF-BB dependent HASMC proliferation. These data demonstrate there is a distinct role especially for cPLA2α on human aortic HASMC proliferation and not migration to PDGF-BB.

Summary Background Short-term survival benefits of endovascular aneurysm repair (EVAR) versus open repair of intact abdominal aortic aneurysms have been shown in randomised trials, but this early survival benefit is lost after a few years. We investigated whether EVAR had a long-term survival benefit compared with open repair. Methods We used data from the EVAR randomised controlled trial (EVAR trial 1), which enrolled 1252 patients from 37 centres in the UK between Sept 1, 1999, and Aug 31, 2004. Patients had to be aged 60 years or older, have aneurysms of at least 5·5 cm in diameter, and deemed suitable and fit for either EVAR or open repair. Eligible patients were randomly assigned (1:1) using computer-generated sequences of randomly permuted blocks stratified by centre to receive either EVAR (n=626) or open repair (n=626). Patients and treating clinicians were aware of group assignments, no masking was used. The primary analysis compared total and aneurysm-related deaths in groups until mid-2015 in the intention-to-treat population. This trial is registered at ISRCTN (ISRCTN55703451). Findings We recruited 1252 patients between Sept 1, 1999, and Aug 31, 2004. 25 patients (four for mortality outcome) were lost to follow-up by June 30, 2015. Over a mean of 12·7 years (SD 1·5; maximum 15·8 years) of follow-up, we recorded 9·3 deaths per 100 person-years in the EVAR group and 8·9 deaths per 100 person-years in the open-repair group (adjusted hazard ratio [HR] 1·11, 95% CI 0·97–1·27, p=0·14). At 0–6 months after randomisation, patients in the EVAR group had a lower mortality (adjusted HR 0·61, 95% CI 0·37–1·02 for total mortality; and 0·47, 0·23–0·93 for aneurysm-related mortality, p=0·031), but beyond 8 years of follow-up open-repair had a significantly lower mortality (adjusted HR 1·25, 95% CI 1·00–1·56, p=0·048 for total mortality; and 5·82, 1·64–20·65, p=0·0064 for aneurysm-related mortality). The increased aneurysm-related mortality in the EVAR group after 8 years was mainly attributable to secondary aneurysm sac rupture (13 deaths [7%] in EVAR vs two [1%] in open repair), with increased cancer mortality also observed in the EVAR group. Interpretation EVAR has an early survival benefit but an inferior late survival compared with open repair, which needs to be addressed by lifelong surveillance of EVAR and re-intervention if necessary. Funding UK National Institute for Health Research, Camelia Botnar Arterial Research Foundation.

Increased force generation and smooth muscle remodeling follow the implantation of saphenous vein as an arterial bypass graft. Previously, we characterized and mapped 129 proteins in human saphenous vein medial smooth muscle using two-dimensional (2-D) PAGE and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Here, we focus on actin filament remodeling in response to simulated arterial flow. Human saphenous vein was exposed to simulated venous or arterial flow for 90 min in vitro, and the contractile medial smooth muscle was dissected out and subjected to 2-D gel electrophoresis using a non-linear immobilized pH 3-10 gradient in the first dimension. Proteins were analyzed quantitatively using PDQuest 2-D software. The actin polymerization inhibitor cytochalasin B (1 microm) prevented increases in force generation after 90 min of simulated arterial flow. At this time point, there were several consistent changes in actin filament-associated protein expression (seven paired vein samples). The heat shock protein HSP27, identified as a three-spot charge train, showed a 1.6-fold increase in abundance (p = 0.01), but with reduced representation of the phosphorylated Ser(82) and Ser(15)Ser(82) isoforms (p = 0.018). The abundance of actin-capping protein alpha2 subunit CapZ had decreased 3-fold, p = 0.04. A 19-kDa proteolytic fragment of actin increased 2-fold, p = 0.04. For the four-spot charge train of gelsolin, there was reduced representation of the more acidic isoforms, p = 0.022. The abundance of other proteins associated with actin filaments, including cofilin and destrin, remained unchanged after arterial flow. Actin filament remodeling with differential expression and/or post-translational modification of proteins involved in capping the barbed end of actin filaments, HSP27 and CapZ, is an early response of contractile saphenous vein smooth muscle cells to hemodynamic stress. The observed changes would favor the generation of contractile stress fibers.

Aim To explore areas of consensus and disagreement concerning the interhospital transfer of patients with a clinical diagnosis of ruptured abdominal aortic aneurysm. Methods A three-round Delphi questionnaire approach was used among vascular and endovascular surgery and emergency medicine specialists to explore patient characteristics and clinical management issues for emergency interhospital transfer. Analysis is based on 38 responses to rounds 2 and 3 (19 vascular surgeons, 6 interventional radiologists, 13 emergency care specialists) with agreement reported when 70% of respondents were in agreement. Results Initially there was agreement that transfer patients should be

Aims \ud \ud To investigate whether aneurysm shape and extent, which indicate whether a patient with ruptured abdominal aortic aneurysm (rAAA) is eligible for endovascular repair (EVAR), influence the outcome of both EVAR and open surgical repair.\ud \ud Methods and results \ud \ud The influence of six morphological parameters (maximum aortic diameter, aneurysm neck diameter, length and conicality, proximal neck angle, and maximum common iliac diameter) on mortality and reinterventions within 30 days was investigated in rAAA patients randomized before morphological assessment in the Immediate Management of the Patient with Rupture: Open Versus Endovascular strategies (IMPROVE) trial. Patients with a proven diagnosis of rAAA, who underwent repair and had their admission computerized tomography scan submitted to the core laboratory, were included. Among 458 patients (364 men, mean age 76 years), who had either EVAR (n = 177) or open repair (n = 281) started, there were 155 deaths and 88 re-interventions within 30 days of randomization analysed according to a pre-specified plan. The mean maximum aortic diameter was 8.6 cm. There were no substantial correlations between the six morphological variables. Aneurysm neck length was shorter in those undergoing open repair (vs. EVAR). Aneurysm neck length (mean 23.3, SD 16.1 mm) was inversely associated with mortality for open repair and overall: adjusted OR 0.72 (95% CI 0.57, 0.92) for each 16 mm (SD) increase in length. There were no convincing associations of morphological parameters with reinterventions.\ud \ud Conclusion \ud \ud Short aneurysm necks adversely influence mortality after open repair of rAAA and preclude conventional EVAR. This may help explain why observational studies, but not randomized trials, have shown an early survival benefit for EVAR.\ud \ud Clinical trial registration: ISRCTN 48334791.

BACKGROUND: Small abdominal aortic aneurysms (AAAs; 3.0-5.4 cm in diameter) are usually asymptomatic and managed by regular ultrasound surveillance until they grow to a diameter threshold (commonly 5.5 cm) at which surgical intervention is considered. The choice of appropriate surveillance intervals is governed by the growth and rupture rates of small AAAs, as well as their relative cost-effectiveness. OBJECTIVES: The aim of this series of studies was to inform the evidence base for small AAA surveillance strategies. This was achieved by literature review, collation and analysis of individual patient data, a focus group and health economic modelling. DATA SOURCES: We undertook systematic literature reviews of growth rates and rupture rates of small AAAs. The databases MEDLINE, EMBASE on OvidSP, Cochrane Central Register of Controlled Trials 2009 Issue 4, ClinicalTrials.gov, and controlled-trials.com were searched from inception up until the end of 2009. We also obtained individual data on 15,475 patients from 18 surveillance studies. REVIEW METHODS: Systematic reviews of publications identified 15 studies providing small AAA growth rates, and 14 studies with small AAA rupture rates, up to December 2009 (later updated to September 2012). We developed statistical methods to analyse individual surveillance data, including the effects of patient characteristics, to inform the choice of surveillance intervals and provide inputs for health economic modelling. We updated an existing health economic model of AAA screening to address the cost-effectiveness of different surveillance intervals. RESULTS: In the literature reviews, the mean growth rate was 2.3 mm/year and the reported rupture rates varied between 0 and 1.6 ruptures per 100 person-years. Growth rates increased markedly with aneurysm diameter, but insufficient detail was available to guide surveillance intervals. Based on individual surveillance data, for each 0.5-cm increase in AAA diameter, growth rates increased by about 0.5 mm/year and rupture rates doubled. To control the risk of exceeding 5.5 cm to below 10% in men, on average a 7-year surveillance interval is sufficient for a 3.0-cm aneurysm, whereas an 8-month interval is necessary for a 5.0-cm aneurysm. To control the risk of rupture to below 1%, the corresponding estimated surveillance intervals are 9 years and 17 months. Average growth rates were higher in smokers (by 0.35 mm/year) and lower in patients with diabetes (by 0.51 mm/year). Rupture rates were almost fourfold higher in women than men, doubled in current smokers and increased with higher blood pressure. Increasing the surveillance interval from 1 to 2 years for the smallest aneurysms (3.0-4.4 cm) decreased costs and led to a positive net benefit. For the larger aneurysms (4.5-5.4 cm), increasing surveillance intervals from 3 to 6 months led to equivalent cost-effectiveness. LIMITATIONS: There were no clear reasons why the growth rates varied substantially between studies. Uniform diagnostic criteria for rupture were not available. The long-term cost-effectiveness results may be susceptible to the modelling assumptions made. CONCLUSIONS: Surveillance intervals of several years are clinically acceptable for men with AAAs in the range 3.0-4.0 cm. Intervals of around 1 year are suitable for 4.0-4.9-cm AAAs, whereas intervals of 6 months would be acceptable for 5.0-5.4-cm AAAs. These intervals are longer than those currently employed in the UK AAA screening programmes. Lengthening surveillance intervals for the smallest aneurysms was also shown to be cost-effective. Future work should focus on optimising surveillance intervals for women, studying whether or not the threshold for surgery should depend on patient characteristics, evaluating the usefulness of surveillance for those with aortic diameters of 2.5-2.9 cm, and developing interventions that may reduce the growth or rupture rates of small AAAs. FUNDING: The National Institute for Health Research Health Technology Assessment programme.

We performed a genome-wide association study on 1,292 individuals with abdominal aortic aneurysms (AAAs) and 30,503 controls from Iceland and The Netherlands, with a follow-up of top markers in up to 3,267 individuals with AAAs and 7,451 controls. The A allele of rs7025486 on 9q33 was found to associate with AAA, with an odds ratio (OR) of 1.21 and P = 4.6 x 10(-10). In tests for association with other vascular diseases, we found that rs7025486[A] is associated with early onset myocardial infarction (OR = 1.18, P = 3.1 x 10(-5)), peripheral arterial disease (OR = 1.14, P = 3.9 x 10(-5)) and pulmonary embolism (OR = 1.20, P = 0.00030), but not with intracranial aneurysm or ischemic stroke. No association was observed between rs7025486[A] and common risk factors for arterial and venous diseases-that is, smoking, lipid levels, obesity, type 2 diabetes and hypertension. Rs7025486 is located within DAB2IP, which encodes an inhibitor of cell growth and survival.

There is a marked variation in tendency of different patients to develop hyperglycemia during peritoneal dialysis. These studies demonstrate a wide range of glucose absorption rates from peritoneal dialysis solutions in 13 uremic patients. The maximum serum glucose conceniration produced by a series

Background: One-third of UK deaths from ruptured abdominal aortic aneurysm (AAA) are in women. In men, national screening programmes reduce deaths from AAA and are cost-effective. The benefits, harms and cost-effectiveness in offering a similar programme to women have not been formally assessed. Methods: A discrete event simulation model was set up for AAA screening, surveillance and intervention. Relevant women-specific parameters were obtained from sources including systematic literature reviews, national registry/administrative databases, major AAA surgery trials, and UK National Health Service reference costs. Findings: AAA screening for women, as currently offered to UK men (at age 65, AAA diagnosis at an aortic diameter of ≥3.0cm and elective repair considered at ≥5.5cm) gave, over a 30-yeartime horizon, an estimated incremental cost effectiveness ratio (ICER) of £30,000 (95% CI 12,000 to 87,000) per quality adjusted life-year (QALY) gained, with 3,900 invitations to screening required to prevent one AAA-death and an over-diagnosis rate of 33%. A modified option for women (screening at age 70, diagnosis at 2.5cm and repair at 5.0cm) was estimated to be more cost-effective, with an ICER of £23,000 (9,500 to 71,000) per QALY and 1,800 invitations to screening required to prevent one AAA-death, but an over-diagnosis rate of 55%. There was considerable uncertainty in the ICER, largely driven by uncertainty about AAA prevalence, the distribution of aortic sizes for women at different ages and the impact of screening on quality-of-life. Interpretation: By UK standards an AAA screening programme for women, mimicking that in men, is unlikely to be cost-effective. Further research on the aortic diameter distribution in women and potential quality of life decrements associated with screening are needed to assess the full benefits and harms of modified options., The UK National Institute for Health Research (NIHR) Health Technology Assessment (HTA) programme commissioned this research (project number 14/179/01).

BACKGROUND: The aim of this study was to develop a 48-h mortality risk score, which included morphology data, for patients with ruptured abdominal aortic aneurysm presenting to an emergency department, and to assess its predictive accuracy and clinical effectiveness in triaging patients to immediate aneurysm repair, transfer or palliative care. METHODS: Data from patients in the IMPROVE (Immediate Management of the Patient With Ruptured Aneurysm: Open Versus Endovascular Repair) randomized trial were used to develop the risk score. Variables considered included age, sex, haemodynamic markers and aortic morphology. Backwards selection was used to identify relevant predictors. Predictive performance was assessed using calibration plots and the C-statistic. Validation of the newly developed and other previously published scores was conducted in four external populations. The net benefit of treating patients based on a risk threshold compared with treating none was quantified. RESULTS: Data from 536 patients in the IMPROVE trial were included. The final variables retained were age, sex, haemoglobin level, serum creatinine level, systolic BP, aortic neck length and angle, and acute myocardial ischaemia. The discrimination of the score for 48-h mortality in the IMPROVE data was reasonable (C-statistic 0·710, 95 per cent c.i. 0·659 to 0·760), but varied in external populations (from 0·652 to 0·761). The new score outperformed other published risk scores in some, but not all, populations. An 8 (95 per cent c.i. 5 to 11) per cent improvement in the C-statistic was estimated compared with using age alone. CONCLUSION: The assessed risk scores did not have sufficient accuracy to enable potentially life-saving decisions to be made regarding intervention. Focus should therefore shift to offering repair to more patients and reducing non-intervention rates, while respecting the wishes of the patient and family.