Mortality following elective abdominal aortic aneurysm repair in women.

BACKGROUND: Previous studies have focused on patient-related risk factors to explain the higher mortality risk in women undergoing elective abdominal aortic aneurysm (AAA) repair. The aim of this study was to evaluate whether hospital-related factors influence outcomes following AAA repair in women. METHODS: Patients undergoing elective AAA repair in 61 hospitals in the Netherlands were identified from the Dutch Surgical Aneurysm Audit registry (2013-2018). A mixed-effects logistic regression analysis was conducted to assess the effect of sex on in-hospital and/or 30-day mortality. This analysis accounted for possible correlation of outcomes among patients who were treated in the same hospital, by adding a hospital-specific random effect to the statistical model. The analysis adjusted for patient-related risk factors and hospital volume of open surgical repair (OSR) and endovascular aneurysm repair (EVAR). RESULTS: Some 12 034 patients were included in the analysis. The mortality rate was higher in women than among men: 53 of 1780 (3.0 per cent) versus 152 of 10 254 (1.5 per cent) respectively. Female sex was significantly associated with mortality after correction for patient- and hospital-related factors (odds ratio 1.68, 95 per cent c.i. 1.20 to 2.37). OSR volume was associated with lower mortality (OR 0.91 (0.85 to 0.95) per 10-procedure increase) whereas no such relationship was identified with EVAR volume (OR 1.03 (1.01 to 1.05) per 10-procedure increase). CONCLUSION: Women are at higher risk of death after abdominal aortic aneurysm repair irrespective of patient- and hospital-related factors.

Patient-Reported Outcomes of Yearly Imaging Surveillance in Patients Following Endovascular Aortic Aneurysm Repair.

Little is known about the impact of standardized imaging surveillance on anxiety levels and well-being of patients after endovascular aortic aneurysm repair (EVAR). We hypothesize that patient anxiety levels increase just before receiving the imaging results compared with standard anxiety levels. METHODS: Prospective cohort study from November 2018 to May 2020 including post-EVAR patients visiting the outpatient clinics of 4 Dutch hospitals for imaging follow-up. The Patient-Reported Outcomes Measurement Information System (PROMIS) was used. Patients completed the PROMIS Anxiety v1.0 Short Form (SF) 4a, PROMIS-Global Health Scale v1.2, and PROMIS-Physical Function v1.2 SF8b at 2 time points: prior to the result of the imaging study (T1: pre-visit) and 6-8 months later (T2: reference measurement). Mean T-scores at T1 were compared to T2, and T2 to the general 65+ Dutch population. RESULTS: Altogether 342 invited patients were eligible, 214 completed the first questionnaire, 189 returned 2 completed questionnaires and 128 patients did not participate. Out of 214 respondents, 195 were male (91.1%) and the mean (standard deviation) age was 75.2 (7.0) years. There were no significant differences between T1 and T2 in anxiety levels (0.48; 95% confidence interval[CI] -0.42-1.38), global mental health (0.27; 95% CI -0.79-0.84), global physical health (0.10; 95% CI -0.38-1.18) and physical function (0.53; 95% CI -0.26-1.32). Compared with the 65+ Dutch population, at T2 patients experienced more anxiety (3.8; 95% CI 2.96-5.54), had worse global physical health (-3.2; 95% CI -4.38 - -2.02) and physical function (-2.4; 95% CI -4.00 - -0.80). Global mental health was similar (-1.0; 95% CI -2.21 - 0.21). CONCLUSIONS: Post-EVAR patients do not experience more anxiety just before receiving surveillance imaging results than outside this period, but do suffer from more anxiety and worse physical outcomes than the 65+ Dutch population.

Systematic review and meta-analysis comparing the autogenous vein bypass versus a prosthetic graft for above-the-knee femoropopliteal bypass surgery in patients with intermittent claudication.

OBJECTIVES: According to guidelines, the autogenous saphenous vein (ASV) is the preferred conduit for femoropopliteal bypass surgery in all patients with peripheral artery disease. However, in contrast to patients with critical limb ischemia (CLI), patients with intermittent claudication (IC) only, tend to have milder disease, and thus a prosthetic graft may be as good as a vein conduit. The objective of this study was to compare patency rates of the ASV and a prosthetic graft in femoropopliteal bypass surgery in patients with IC. METHODS: A systematic literature search was performed in the PubMed, Embase, and Cochrane databases to identify randomized controlled trials comparing prosthetic graft versus ASV in patients with IC. Articles with a mixed IC and CLI study population were included if more than 50% of the study cohort was treated for IC. Primary analysis was performed on IC patients only. Secondary analysis was performed on the mixed group. The primary endpoint was short- and long-term patency and secondary endpoints were complications, limb salvage, and mortality. RESULTS: In total, six studies with 524 patients were included. Only two studies reported solely on patients with IC. All these patients underwent above-the-knee bypasses and average patency rates at one and 5 years were 88% and 76% vs 81% and 68% in the ASV and the PTFE groups, respectively. One and five-year patency was not statistically different between the groups (OR 5.21; 95% CI 0.60-45.36 and OR 2.10; 95% CI 0.88-5.01). In a mixed population of patients with IC and CLI (84% IC patients), 1 year patency was comparable (OR 1.40; 95% CI 0.87-2.25). However, after a follow-up of over 3 years, this mixed group had significantly higher patency rates in favour of the ASV (OR 2.06; 95 % CI 1.30-3.26). Complication and amputation rates were comparable in both groups. CONCLUSIONS: Limited data are available for patients receiving above-the-knee femoropopliteal bypass for intermittent claudication. The ASV remains the conduit of choice for femoropopliteal bypass surgery. However, the prosthetic conduit seems a feasible alternative for patients with intermittent claudication in whom the ASV is not present or unsuitable.

The impact of O2/Ar ratio on morphology and functional properties in reactive sputtering of metal oxide thin films.

Morphology is a critical parameter for various thin film applications, influencing properties like wetting, catalytic performance and sensing efficiency. In this work, we report on the impact of oxygen partial flow on the morphology of ceramic thin films deposited by pulsed DC reactive magnetron sputtering. The influence of O2/Ar ratio was studied on three different model systems, namely Al2O3, CuO and TiO2. The availability of oxygen during reactive sputtering is a key parameter for a versatile tailoring of thin film morphology over a broad range of nanostructures. TiO2 thin films with high photocatalytic performance (up to 95% conversion in 7 h) were prepared, exhibiting a network of nanoscopic cracks between columnar anatase structures. In contrast, amorphous thin films without such crack networks and with high resiliency to crystallization even up to 950 °C were obtained for Al2O3. Finally, we report on CuO thin films with well aligned crystalline nanocolumns and outstanding gas sensing performance for volatile organic compounds as well as hydrogen gas, showing gas responses up to 35% and fast response in the range of a few seconds.

Self-organized nanocrack networks: a pathway to enlarge catalytic surface area in sputtered ceramic thin films, showcased for photocatalytic TiO2.

Sputter deposited photocatalytic thin films offer high adherence and mechanical stability, but typically are outperformed in their photocatalytic properties by colloidal TiO2 nanostructures, which in turn typically suffer from problematic removal. Here we report on thermally controlled nanocrack formation as a feasible and batch applicable approach to enhance the photocatalytic performance of well adhering, reactively sputtered TiO2 thin films. Networks of nanoscopic cracks were induced into tailored columnar TiO2 thin films by thermal annealing. These deep trenches are separating small bundles of TiO2 columns, adding their flanks to the overall catalytically active surface area. The variation of thin film thickness reveals a critical layer thickness for initial nanocrack network formation, which was found to be about 400 nm in case of TiO2. The columnar morphology of the as deposited TiO2 layer with weak bonds between respective columns and with strong bonds to the substrate is of crucial importance for the formation of nanocrack networks. A beneficial effect of nanocracking on the photocatalytic performance was experimentally observed. It was correlated by a simple geometric model for explaining the positive impact of the crack induced enlargement of active surface area on photocatalytic efficiency. The presented method of nanocrack network formation is principally not limited to TiO2 and is therefore seen as a promising candidate for utilizing increased surface area by controlled crack formation in ceramic thin films in general.

The use of thoracic stent grafts for endovascular repair of abdominal aortic aneurysms.

Objectives Stent grafts for endovascular repair of infrarenal aneurysms are commercially available for aortic necks up to 32 mm in diameter. The aim of this study was to evaluate the feasibility of endovascular repair with large thoracic stent grafts in the infrarenal position to obtain adequate proximal seal in wider necks. Methods All patients who underwent endovascular aneurysm repair using thoracic stent grafts with diameters greater than 36 mm between 2012 and 2016 were included. Follow-up consisted of CT angiography after six weeks and annual duplex thereafter. Results Eleven patients with wide infrarenal aortic necks received endovascular repair with thoracic stent grafts. The median diameter of the aneurysms was 60 mm (range 52-78 mm) and the median aortic neck diameter was 37 mm (range 28-43 mm). Thoracic stent grafts were oversized by a median of 14% (range 2-43%). On completion angiography, one type I and two type II endoleaks were observed but did not require reintervention. One patient experienced graft migration with aneurysm sac expansion and needed conversion to open repair. Median follow-up time was 14 months (range 2-53 months), during which three patients died, including one aneurysm-related death. Conclusions Endovascular repair using thoracic stent grafts for patients with wide aortic necks is feasible. In these patients, the technique may be a reasonable alternative to complex endovascular repair with fenestrated, branched, or chimney grafts. However, more experience and longer follow-up are required to determine its position within the endovascular armamentarium.

Systematic review of mortality risk prediction models in the era of endovascular abdominal aortic aneurysm surgery.

BACKGROUND: The introduction of endovascular aneurysm repair (EVAR) has reduced perioperative mortality after abdominal aortic aneurysm (AAA) surgery. The objective of this systematic review was to assess existing mortality risk prediction models, and identify which are most useful for patients undergoing AAA repair by either EVAR or open surgical repair. METHODS: A systematic search of the literature was conducted for perioperative mortality risk prediction models for patients with AAA published since 2006. PRISMA guidelines were used; quality was appraised, and data were extracted and interpreted following the CHARMS guidelines. RESULTS: Some 3903 studies were identified, of which 27 were selected. A total of 13 risk prediction models have been developed and directly validated. Most models were based on a UK or US population. The best performing models regarding both applicability and discrimination were the perioperative British Aneurysm Repair score (C-statistic 0·83) and the preoperative Vascular Biochemistry and Haematology Outcome Model (C-statistic 0·85), but both lacked substantial external validation. CONCLUSION: Mortality risk prediction in AAA surgery has been modelled extensively, but many of these models are weak methodologically and have highly variable performance across different populations. New models are unlikely to be helpful; instead case-mix correction should be modelled and adapted to the population of interest using the relevant mortality predictors.

Improved Adherence to a Stepped-care Model Reduces Costs of Intermittent Claudication Treatment in The Netherlands.

OBJECTIVE/BACKGROUND: A previous budget impact analysis regarding a supervised exercise therapy (SET) first treatment strategy (stepped care model [SCM]) for Dutch patients with intermittent claudication (IC) showed a low referral rate in 2009, despite solid evidence of the effectiveness of SET programs. Recently, several campaigns have stimulated stakeholders in the field to adopt a SET first strategy in patients with IC. The aim of the present study was to reassess SCM adherence after a 2 year period. METHODS: IC related invoices of patients in 2011 were obtained from a large Dutch health insurance company (3.5 million persons). Patients were divided into two groups based on their initial treatment. A SET group had started SET between 12 months before (initiated by general practitioner) and 3 months after (initiated by vascular surgeon) presentation at a vascular surgery outpatient clinic. An intervention (INT) group was treated by revascularisation within 3 months of outpatient presentation. Costs of IC treatment in this 2011 cohort were compared with the earlier 2009 cohort. RESULTS: IC related invoices of 4135 patients were available. In 2011, the initial treatment was SET in 56% (2009: 34%; +22% [p < .001]) and INT in 44% (2009: 66%; -22% [p < .001]) of the IC population. Additional revascularisation was performed in 19% of patients in the SET group (2009: 6%; +13% [p < .001]) and also in 19% of patients in the INT group (2009: 35%; -16% [p < .001]). Later on, 29% of patients in the INT group were referred for SET (2009: 10%; +19% [p < .001]). Average costs of IC treatment per patient in 2011 were 6% lower than in 2009 (€6885 vs. €7300; p = .020). CONCLUSION: A 22% increase in adherence to SET as a first treatment strategy in Dutch patients with IC was attained between 2009 and 2011. This shift suggests successful SCM implementation resulting in lower costs for the national healthcare system.

Venous Arterialisation for Salvage of Critically Ischaemic Limbs: A Systematic Review and Meta-Analysis.

BACKGROUND: Critical limb ischaemia (CLI) is the end stage of peripheral artery disease (PAD) and is associated with high amputation and mortality rates and poor quality of life. For CLI patients with no revascularisation options, venous arterialisation could be a last resort for limb salvage. OBJECTIVE: To review the literature on the clinical effectiveness of venous arterialisation for lower limb salvage in CLI patients with no revascularisation options. METHOD: Different databases were searched for papers published between January 1966 and January 2016. The criteria for eligible articles were studies describing outcomes of venous arterialisation, published in English, human studies, and with the full text available. Additionally, studies were excluded if they did not report limb salvage, wound healing or amputation as outcome measures. The primary outcome measure was post-operative limb salvage at 12 months. Secondary outcome measures were 30 day or in-hospital mortality, survival, patency, technical success, and wound healing. RESULTS: Fifteen articles met the inclusion criteria. The included studies described 768 patients. According to the MINORS score, methodological quality was moderate to poor. The estimated pooled limb salvage rate at one year was 75% (0.75, 95% CI 0.70-0.81). Thirty day or in-hospital mortality was reported in 12 studies and ranged from 0 to 10%. Overall survival was reported in 10 studies and ranged from 54% to 100% with a mean follow-up ranging from 5 to 60 months. Six studies reported on patency of the venous arterialisations performed, with a range of 59-71% at 12 months. CONCLUSION: In this systematic review on venous arterialisation in patients with non-reconstructable critical limb ischaemia, the pooled proportion of limb salvage at 12 months was 75%. Venous arterialisation could be a valuable treatment option in patients facing amputation of the affected limb; however, the current evidence is of low quality.

Adjusted Hospital Outcomes of Abdominal Aortic Aneurysm Surgery Reported in the Dutch Surgical Aneurysm Audit.

OBJECTIVE/BACKGROUND: The Dutch Surgical Aneurysm Audit (DSAA) is mandatory for all patients with primary abdominal aortic aneurysms (AAAs) in the Netherlands. The aims are to present the observed outcomes of AAA surgery against the predicted outcomes by means of V-POSSUM (Vascular-Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity). Adjusted mortality was calculated by the original and re-estimated V(physiology)-POSSUM for hospital comparisons. METHODS: All patients operated on from January 2013 to December 2014 were included for analysis. Calibration and discrimination of V-POSSUM and V(p)-POSSUM was analysed. Mortality was benchmarked by means of the original V(p)-POSSUM formula and risk-adjusted by the re-estimated V(p)-POSSUM on the DSAA. RESULTS: In total, 5898 patients were included for analysis: 4579 with elective AAA (EAAA) and 1319 with acute abdominal aortic aneurysm (AAAA), acute symptomatic (SAAA; n = 371) or ruptured (RAAA; n = 948). The percentage of endovascular aneurysm repair (EVAR) varied between hospitals but showed no relation to hospital volume (EAAA: p = .12; AAAA: p = .07). EAAA, SAAA, and RAAA mortality was, respectively, 1.9%, 7.5%, and 28.7%. Elective mortality was 0.9% after EVAR and 5.0% after open surgical repair versus 15.6% and 27.4%, respectively, after AAAA. V-POSSUM overestimated mortality in most EAAA risk groups (p < .01). The discriminative ability of V-POSSUM in EAAA was moderate (C-statistic: .719) and poor for V(p)-POSSUM (C-statistic: .665). V-POSSUM in AAAA repair overestimated in high risk groups, and underestimated in low risk groups (p < .01). The discriminative ability in AAAA of V-POSSUM was moderate (.713) and of V(p)-POSSUM poor (.688). Risk adjustment by the re-estimated V(p)-POSSUM did not have any effect on hospital variation in EAAA but did in AAAA. CONCLUSION: Mortality in the DSAA was in line with the literature but is not discriminative for hospital comparisons in EAAA. Adjusting for V(p)-POSSUM, revealed no association between hospital volume and treatment or outcome. Risk adjustment for case mix by V(p)-POSSUM in patients with AAAA has been shown to be important.

Development and External Validation of a Model Predicting Death After Surgery in Patients With a Ruptured Abdominal Aortic Aneurysm: The Dutch Aneurysm Score.

OBJECTIVE: The decision whether or not to proceed with surgical intervention of a patient with a ruptured abdominal aortic aneurysm (rAAA) is very difficult in daily practice. The primary objective of the present study was to develop and to externally validate a new prediction model: the Dutch Aneurysm Score (DAS). METHODS: With a prospective cohort of 10 hospitals (n = 508) the DAS was developed using a multivariate logistic regression model. Two retrospective cohorts with rAAA patients from two hospitals (n = 373) were used for external validation. The primary outcome was the combined 30 day and in-hospital death rate. Discrimination (AUC), calibration plots, and the ability to identify high risk patients were compared with the more commonly used Glasgow Aneurysm Score (GAS). RESULTS: After multivariate logistic regression, four pre-operative variables were identified: age, lowest in hospital systolic blood pressure, cardiopulmonary resuscitation, and haemoglobin level. The area under the receiver operating curve (AUC) for the DAS was 0.77 (95% CI 0.72-0.82) compared with the GAS with an AUC of 0.72 (95% CI 0.67-0.77). The DAS showed a death rate in patients with a predicted death rate ≥80% of 83%. CONCLUSIONS: The present study shows that the DAS has a higher discriminative performance (AUC) compared with the GAS. All clinical variables used for the DAS are easy to obtain. Identification of low risk patients with the DAS can potentially reduce turndown rates. The DAS can reliably be used by clinicians to make a more informed decision in dialogue with the patient and their family whether or not to proceed with surgical intervention.

Aortic Curvature Instead of Angulation Allows Improved Estimation of the True Aorto-iliac Trajectory.

OBJECTIVE: Supra- and infrarenal aortic neck angulation have been associated with complications after endovascular aortic aneurysm repair. However, a uniform angulation measurement method is lacking and the concept of angulation suggests a triangular oversimplification of the aortic anatomy. (Semi-)automated calculation of curvature along the center luminal line describes the actual trajectory of the aorta. This study proposes a methodology for calculating aortic (neck) curvature and suggests an additional method based on available tools in current workstations: curvature by digital calipers (CDC). METHODS: Proprietary custom software was developed for automatic calculation of the severity and location of the largest supra- and infrarenal curvature over the center luminal line. Twenty-four patients with severe supra- or infrarenal angulations (≥45°) and 11 patients with small to moderate angulations (<45°) were included. Both CDC and angulation were measured by two independent observers on the pre- and postoperative computed tomographic angiography scans. The relationships between actual curvature and CDC and angulation were visualized and tested with Pearson's correlation coefficient. The CDC was also fully automatically calculated with proprietary custom software. The difference between manual and automatic determination of CDC was tested with a paired Student t test. A p-value was considered significant when two-tailed α < .05. RESULTS: The correlation between actual curvature and manual CDC is strong (.586-.962) and even stronger for automatic CDC (.865-.961). The correlation between actual curvature and angulation is much lower (.410-.737). Flow direction angulation values overestimate CDC measurements by 60%, with larger variance. No significant difference was found in automatically calculated CDC values and manually measured CDC values. CONCLUSION: Curvature calculation of the aortic neck improves determination of the true aortic trajectory. Automatic calculation of the actual curvature is preferable, but measurement or calculation of the curvature by digital calipers is a valid alternative if actual curvature is not at hand.

Shared Decision Making in Vascular Surgery: An Exploratory Study.

OBJECTIVES: Shared decision making (SDM) is a process in which patients and their doctors collaborate in choosing a suitable treatment option by incorporating patient values and preferences, as well as the best available evidence. Particularly in vascular surgery, several conditions seem suitable for SDM because there are multiple treatment options. The objective of this study was to assess the degree of SDM behaviour in vascular surgery. METHODS: Vascular surgeons of four Dutch hospitals selected consultations with patients who were facing a treatment decision. Immediately after the consultation, patients and surgeons completed the (subjective) SDM Q-9 and SDM Q-doc questionnaires respectively, to appreciate the perceived level of SDM behaviour. Two evaluators independently and objectively rated SDM behaviour in the audiotaped consultations, using the Observing Patient Involvement (OPTION-12) scale. RESULTS: Nine vascular surgeons and three vascular surgeons in training conducted 54 consultations. The patients' median SDM Q-9 score was high, 93% (IQR 79-100%), and 16/54 (29.6%) of them gave the maximum score. The surgeons' median score was also high, 84% (IQR 73-92%), while 4/54 (7.4%) gave the maximum score. In contrast, mean OPTION score was 31% (SD 11%). Surgeons hardly ever asked the patients for their preferred approach to receive information, whether they had understood the provided information, and how they would like to be involved in SDM. CONCLUSIONS: Currently, objective SDM behaviour among vascular surgeons is limited, even though the presented disorders allow for SDM. Hence, SDM in vascular surgical consultations could be improved by increasing the patients' and surgeons' awareness and knowledge about the concept of SDM.

Cost-effectiveness of Elective Endovascular Aneurysm Repair Versus Open Surgical Repair of Abdominal Aortic Aneurysms.

OBJECTIVE/BACKGROUND: The aim of this study was to estimate the lifetime cost-effectiveness of endovascular aneurysm repair (EVAR) versus open surgical repair (OSR) in the Netherlands, based on recently published literature. METHODS: A model was developed to simulate a cohort of individuals (age 72 years, 87% men) with an abdominal aortic aneurysm (AAA) diameter of at least 5.5 cm and considered fit for both repairs. The model consisted of two sub-models that estimated the lifetime cost-effectiveness of EVAR versus OSR: (1) a decision tree for the first 30 post-operative days; and (2) a Markov model for the period thereafter (31 days-30 years). RESULTS: In the base case analysis, EVAR was slightly more effective (4.704 vs. 4.669 quality adjusted life years) and less expensive (€24,483 vs. €25,595) than OSR. Improved effectiveness occurs because EVAR can reduce 30 day mortality risk, as well as the risk of events following the procedure, while lower costs are primarily due to a reduction in length of hospital stay. The cost-effectiveness of EVAR is highly dependent on the price of the EVAR device and the reduction in hospital stay, complications, and 30 day mortality. CONCLUSION: EVAR and OSR can be considered equally effective, while EVAR can be cost saving compared with OSR. EVAR can therefore be considered as a cost-effective solution for patients with AAAs.

Changes in Aortoiliac Anatomy After Elective Treatment of Infrarenal Abdominal Aortic Aneurysms with a Sac Anchoring Endoprosthesis.

OBJECTIVE: Endovascular aortic sealing (EVAS) with the Nellix endosystem (Endologix, Irvine, CA, USA) is a new concept to treat infrarenal abdominal aortic aneurysms (AAAs). By sealing the aneurysm, potential endoleaks may be avoided. Early results of EVAS are good, but no data have been published regarding peri-procedural changes in aortoiliac anatomy. In this study, 27 consecutive patients who underwent elective EVAS repair of an AAA were reviewed. METHOD: Specific AAA (diameter, length from renal arteries to aortic bifurcation, supra- and infrarenal neck angulation, AAA volume, thrombus volume, and flow lumen volume), and iliac artery characteristics (length, angulation, location of most severe angulation with reference to the origin of the common iliac artery) were determined from pre- and post-procedural reconstructed computed tomography angiograms. RESULTS: No type I or II endoleaks were seen at 30 day follow up. Total AAA volume, suprarenal and infrarenal angulation, as well as aortic neck diameter did not change significantly post-EVAS. AAA flow lumen increased significantly (mean difference -4.4 mL, 95% CI 2.0 to -8.6 mL) and AAA thrombus volume decreased (mean difference 3.2 mL, 95% CI 2.0 to -1.1 mL). AAA length (125.7 mm vs. 123.1 mm), left common iliac artery length (57.6 mm vs. 55.3 mm), and right and left maximum iliac artery angulation (right 37.4° vs. 32.2°; left: 43.9° vs. 38.4°) were reduced significantly and the location of maximum angulation was further from the iliac artery origin post-EVAS, suggesting slight straightening of the aortoiliac anatomy. CONCLUSION: Most aortoiliac anatomic characteristics remained unchanged post-EVAS. Filling of the endobags to a pressure of 180 mmHg may lead to lost thrombus volume in some patients, probably because liquid is squeezed into lumbar or the inferior mesenteric artery. The absolute differences in pre- and post-EVAS aortoiliac lengths were small, so pre-operative sizing is accurate for determining stent length.

Fate of patients unwilling or unsuitable to undergo surgical intervention for a ruptured abdominal aortic aneurysm.

INTRODUCTION: The primary objective of this study was to assess the duration of in-hospital survival in 57 patients with ruptured abdominal aortic aneurysms (RAAA) who did not undergo surgical intervention. REPORT: Two hours after registration in the emergency room, 58% (95% CI 45-71) of patients were still alive. The median survival was 2.2 hours (interquartile range 1-18). In a subgroup including 26 haemodynamically stable patients, survival after 2 hours was 96% (95% CI 89-100). CONCLUSION: In patients with an RAAA without surgical intervention, the duration of in-hospital survival is limited. However, a group of haemodynamically stable patients can be identified in whom survival is much longer.

Midterm Re-interventions and Survival After Endovascular Versus Open Repair for Ruptured Abdominal Aortic Aneurysm.

OBJECTIVE: To compare the midterm re-intervention and survival rates after EVAR and OR for ruptured abdominal aortic aneurysms (RAAA). METHODS: Observational cohort study including all consecutive RAAA patients between 2004 and 2011 in 10 hospitals in the Amsterdam ambulance region. The primary end point was re-interventions within 5 years of the primary intervention. The secondary end point was death. The outcomes were estimated by survival analyses, compared using the logrank test, and subsequently adjusted for possible confounders using Cox proportional hazard models. Re-interventions were estimated in all patients and in patients who survived their hospital stay. RESULTS: Of 467 patients with a RAAA, 73 were treated by EVAR and 394 by OR. Five years after the primary intervention, the rates of freedom from re-intervention were 55% for EVAR (26/73, 95% CI: 41-69%) and 60% for OR (130/394, 95% CI: 55-66%) (p = .96). After adjustment for age, sex, comorbidity, and pre-operative hemodynamic stability, the risk of re-intervention was similar (HR 1.01, 95% CI: 0.65-1.55). The survival rates were 36% for EVAR (45/73, 95% CI: 24-47%) and 38% for OR (235/394, 95% CI: 33-43%) (p = .83). In 297 patients who survived their hospital stay, the rates of freedom from re-intervention were 66% for EVAR (15/54, 95% CI: 52-81%) and 90% for OR (20/243, 95% CI: 86-95%) (p < .01). After adjustment for age and sex, the risk of re-intervention was higher after EVAR (HR 0.27, 95% CI: 0.14-0.52). CONCLUSIONS: Five years after the primary intervention, endovascular and open repair for ruptured abdominal aortic aneurysm resulted in similar re-intervention and survival rates. However, in patients who survived their hospital stay the re-intervention rate was higher for EVAR than for OR.

Editor's Choice--External Validation of Models Predicting Survival After Ruptured Abdominal Aortic Aneurysm Repair.

OBJECTIVE: Prediction of survival after intervention for ruptured abdominal aortic aneurysms (RAAA) may support case mix comparison and tailor the prognosis for patients and relatives. The objective of this study was to assess the performance of four prediction models: the updated Glasgow Aneurysm Score (GAS), the Vancouver scoring system, the Edinburgh Ruptured Aneurysm Score (ERAS), and the Hardman index. DESIGN, MATERIALS, AND METHODS: This was a retrospective cohort study in 449 patients in ten hospitals with a RAAA (intervention between 2004 and 2011). The primary endpoint was combined 30 day or in hospital death.The accuracy of the prediction models was assessed for discrimination (area under the curve [AUC]). An AUC>0.70 was considered sufficiently accurate. In studies with sufficiently accurate discrimination, correspondence between the predicted and observed outcomes (i.e. calibration) was recalculated. RESULTS: The AUC of the updated GAS was 0.71 (95% confidence interval [CI] 0.66-0.76), of the Vancouver score was 0.72 (95% CI 0.67-0.77), and of the ERAS was 0.58 (95% CI 0.52-0.65). After recalibration, predictions by the updated GAS slightly overestimated the death rate, with a predicted death rate 60% versus observed death rate 54% (95% CI 44-64%). After recalibration, predictions by the Vancouver score considerably overestimated the death rate, with a predicted death rate 82% versus observed death rate 62% (95% CI 52-71%). Performance of the Hardman index could not be assessed on discrimination and calibration, because in 57% of patients electrocardiograms were missing. CONCLUSIONS: Concerning discrimination and calibration, the updated GAS most accurately predicted death after intervention for a RAAA. However, the updated GAS did not identify patients with a ≥95% predicted death rate, and therefore cannot reliably support the decision to withhold intervention.

Effect of regional cooperation on outcomes from ruptured abdominal aortic aneurysm.

BACKGROUND: Care for patients with a ruptured abdominal aortic aneurysm (rAAA) in the Amsterdam ambulance region (The Netherlands) was concentrated into vascular centres with a 24-h full emergency vascular service in cooperation with seven referring regional hospitals. Previous population-based survival after rAAA in the Netherlands was 46 (95 per cent confidence interval (c.i.) 43 to 49) per cent. It was hypothesized that regional cooperation would improve survival. METHODS: This was a prospective observational cohort study carried out simultaneously with the Amsterdam Acute Aneurysm Trial. Consecutive patients with an rAAA between 2004 and 2011 in all ten hospitals in the Amsterdam region were included. The primary outcome was 30-day survival after admission. Multivariable logistic regression, including age, sex, co-morbidity, intervention (endovascular or open repair), preoperative systolic blood pressure, cardiopulmonary resuscitation and year of intervention, was used to assess the influence of hospital setting on survival. RESULTS: Of 453 patients with rAAA from the Amsterdam ambulance region, 61 did not undergo intervention; 352 patients were treated surgically at a vascular centre and 40 at a referring hospital. The regional survival rate was 58.5 (95 per cent c.i. 53.9 to 62.9) per cent (265 of 453). After multivariable adjustment, patients treated at a vascular centre had a higher survival rate than patients treated surgically at a referring hospital (adjusted odds ratio 3.18, 95 per cent c.i. 1.43 to 7.04). CONCLUSION: After regional cooperation, overall survival of patients with an rAAA improved. Most patients were treated in a vascular centre and in these patients survival rates were optimal.

Cost-effectiveness and cost-utility of endovascular versus open repair of ruptured abdominal aortic aneurysm in the Amsterdam Acute Aneurysm Trial.

BACKGROUND: Minimally invasive endovascular aneurysm repair (EVAR) could be a surgical technique that improves outcome of patients with ruptured abdominal aortic aneurysm (rAAA). The aim of this study was to analyse the cost-effectiveness and cost-utility of EVAR compared with standard open repair (OR) in the treatment of rAAA, with costs per 30-day and 6-month survivor as outcome parameters. METHODS: Resource use was determined from the Amsterdam Acute Aneurysm (AJAX) trial, a multicentre randomized trial comparing EVAR with OR in patients with rAAA. The analysis was performed from a provider perspective. All costs were calculated as if all patients had been treated in the same hospital (Onze Lieve Vrouwe Gasthuis, teaching hospital). RESULTS: A total of 116 patients were randomized. The 30-day mortality rate was 21 per cent after EVAR and 25 per cent for OR: absolute risk reduction (ARR) 4·4 (95 per cent confidence interval (c.i.) -11·0 to 19·7) per cent. At 6 months, the total mortality rate for EVAR was 28 per cent, compared with 31 per cent among those assigned to OR: ARR 2·4 (-14·2 to 19·0) per cent. The mean cost difference between EVAR and OR was €5306 (95 per cent c.i. -1854 to 12,659) at 30 days and €10,189 (-2477 to 24,506) at 6 months. The incremental cost-effectiveness ratio per prevented death was €120,591 at 30 days and €424,542 at 6 months. There was no significant difference in quality of life between EVAR and OR. Nor was EVAR superior regarding cost-utility. CONCLUSION: EVAR may be more effective for rAAA, but its increased costs mean that it is unaffordable based on current standards of societal willingness-to-pay for health gains.