Variations in Abdominal Aortic Aneurysm Care: A Report From the International Consortium of Vascular Registries

Pathogenic mechanisms and the potential of drug therapies for aortic aneurysm

Aortic aneurysm is a permanent focal dilation of the aorta. It is usually an asymptomatic disease but can lead to sudden death due to aortic rupture. Aortic aneurysm-related mortalities are estimated at ∼200,000 deaths per year worldwide. Because no pharmacological treatment has been found to be effective so far, surgical repair remains the only treatment for aortic aneurysm. Aortic aneurysm results from changes in the aortic wall structure due to loss of smooth muscle cells and degradation of the extracellular matrix and can form in different regions of the aorta. Research over the past decade has identified novel contributors to aneurysm formation and progression. The present review provides an overview of cellular and noncellular factors as well as enzymes that process extracellular matrix and regulate cellular functions (e.g., matrix metalloproteinases, granzymes, and cathepsins) in the context of aneurysm pathogenesis. An update of clinical trials focusing on therapeutic strategies to slow abdominal aortic aneurysm growth and efforts underway to develop effective pharmacological treatments is also provided.

Regional variation in endovascular treatment rate and in-hospital mortality of abdominal aortic aneurysms in Germany

Summary: Background: Abdominal aortic aneurysms (AAA) can be treated by either open surgery (OAR) or endovascular aortic repair (EVAR). The aim of this study was to analyze regional variations in application of (EVAR) and in-hospital mortality after intact AAA (iAAA) repair. Methods: Using data provided by the German Federal Statistical Office, a nationwide analysis for 2012 to 2014 was conducted. Patients with a diagnosis of iAAA (I71.4) and corresponding procedure codes for OAR (5-384.5/7) or EVAR (5-38a.1) were included. Odds ratios (ORs) for use of EVAR (proportion of EVAR among total EVAR + OAR cases) and mortality were calculated for all regions in Germany. ORs for EVAR use were adjusted for age, sex, and risk (Elixhauser score). ORs for mortality were additionally adjusted for type of procedure (OAR/EVAR). Results: Finally, 31,757 procedures for iAAA were included. Median age of all patients was 73 years (interquartile range 67–78 years) and 87.1 % were male. The mean proportion of EVAR procedures was 72.6 %; however, the application of EVAR for repair of iAAA varied widely depending on region. The lowest unadjusted regional rate of EVAR use was 48.8 %, while the highest was 92.5 %. After adjustment, the lowest regional OR for EVAR use (compared to the nationwide mean) was 0.23 (95 % confidence interval [0.15–0.36]), the highest 5.93 [1.79–19.65]. Overall in-hospital mortality was 2.9 % (OAR 6.2 %; EVAR 1.7 %). The adjusted regional OR for mortality ranged from 0.31 [0.07–1.42] to 4.98 [2.08–11.93]. Conclusions: This study reveals variations in use of EVAR and in-hospital mortality for iAAA treatment in Germany. This may imply that selection of treatment might not only be influenced by patient characteristics, but also by regional location. These results need to be taken into account when discussing centralization of AAA treatment in Germany.

Geographic disparities in the application of endovascular repair of unruptured abdominal aortic aneurysm - Polish population analysis

PURPOSE

Differences between the regions of the same country regarding the management of abdominal aortic aneurysm (AAA) have rarely been published. The aim of the study was to analyze the absolute and relative number of unruptured AAA repairs, utilizing endovascular aneurysm repair (EVAR) vs. open aneurysm repairs (OAR) and compare the AAA patients population from all 16 administrative districts in Poland.

MATERIAL AND METHODS

We used the Polish National Health Fund data of all patients who underwent elective treatment of AAA between 1^st January 2011 and 22^nd March 2016 and analyzed the absolute/relative number of all AAA repairs, OAR, EVAR and incidence of concomitant diseases in distinctive regions. Relationships between the utilization of EVAR and the number of procedures, age, gender and concomitant diseases were studied.

RESULTS

A total of 7805 patients (mean age 70.9 ± 8.1 yrs) underwent OAR (n = 2336) or EVAR (n = 5469). The age and the incidence of concomitant diseases differed significantly between districts. The highest absolute number of all repairs was performed in the Masovian district (n = 1442), while the highest relative number of all repairs in the Lublin district (36.3/100,000 65+/year). The utilization of EVAR ranged from 34.5% to 93.9% and correlated positively with the number of EVAR, age and chronic obstructive pulmonary disease occurrence and negatively with OAR number.

CONCLUSIONS

Striking differences in the relative numbers of unruptured AAA repairs and in the population characteristics in various districts of the country point to the possibility of different health needs in the regions and variations in standards of care.

Artificial intelligence in abdominal aortic aneurysm

OBJECTIVE

Abdominal aortic aneurysm (AAA) is a life-threatening disease, and the only curative treatment relies on open or endovascular repair. The decision to treat relies on the evaluation of the risk of AAA growth and rupture, which can be difficult to assess in practice. Artificial intelligence (AI) has revealed new insights into the management of cardiovascular diseases, but its application in AAA has so far been poorly described. The aim of this review was to summarize the current knowledge on the potential applications of AI in patients with AAA.

METHODS

A comprehensive literature review was performed. The MEDLINE database was searched according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The search strategy used a combination of keywords and included studies using AI in patients with AAA published between May 2019 and January 2000. Two authors independently screened titles and abstracts and performed data extraction. The search of published literature identified 34 studies with distinct methodologies, aims, and study designs.

RESULTS

AI was used in patients with AAA to improve image segmentation and for quantitative analysis and characterization of AAA morphology, geometry, and fluid dynamics. AI allowed computation of large data sets to identify patterns that may be predictive of AAA growth and rupture. Several predictive and prognostic programs were also developed to assess patients' postoperative outcomes, including mortality and complications after endovascular aneurysm repair.

CONCLUSIONS

AI represents a useful tool in the interpretation and analysis of AAA imaging by enabling automatic quantitative measurements and morphologic characterization. It could be used to help surgeons in preoperative planning. AI-driven data management may lead to the development of computational programs for the prediction of AAA evolution and risk of rupture as well as postoperative outcomes. AI could also be used to better evaluate the indications and types of surgical treatment and to plan the postoperative follow-up. AI represents an attractive tool for decision-making and may facilitate development of personalized therapeutic approaches for patients with AAA.

Influence of patient-specific rehearsal on operative metrics and technical success for endovascular aneurysm repair

INTRODUCTION

Patient-specific rehearsal (PsR) is a recent technology within virtual reality (VR) simulation that lets the operators train on patient-specific data in a simulated environment prior to the procedure. Endovascular aneurysm repair (EVAR) is a complex procedure where operative metrics and technical success might improve after PsR.

MATERIAL AND METHODS

We compared technical success and operative metrics (endovascular procedure time, contralateral gate cannulation time, fluoroscopy time, total radiation dose, number of angiograms and contrast medium use) between 30 patients, where the operators performed PsR (the PsR group), and 30 patients without PsR (the control group).

RESULTS

The endovascular procedure time was significantly shorter in the PsR group than in the control group (median 44 versus 55 min, p = .017). The other operative metrics were similar. Technical success rates were higher in the PsR group, 96.7% primary and assisted primary outcome versus 90.0% in the control group. The differences were not significant (p = .076).

CONCLUSIONS

PsR before EVAR reduced endovascular procedure time, and our results indicate that it might improve technical success, but further studies are needed to confirm those results.

Patient information sources when facing repair of abdominal aortic aneurysm

OBJECTIVE

Shared medical decision making is most important when there are competing options for repair such as in treatment of abdominal aortic aneurysm (AAA). We sought to understand the sources of patients' pre-existing knowledge about AAA to better inform treating physicians about patients' needs for preoperative counseling.

METHODS

We performed a multicenter survey of patients facing AAA repair at 20 Veterans Affairs hospitals across the United States as part of the Preferences for Open Versus Endovascular Repair of AAA study. A validated survey instrument was administered to examine the sources of information available and commonly used by patients to learn about their repair options. The survey was administered by study personnel before the patient had any interaction with the vascular surgeon because survey data were collected before the vascular clinic visit.

RESULTS

Preliminary analysis of data from 99 patients showed that our cohort was primarily male (99%) and elderly (mean age 73 years). Patients commonly had a history of hypertension (86%), prior myocardial infarction (32%), diabetes (32%), and were overweight (58%). Patients arrived at their surgeon's office appointment with limited information. A majority of patients (52%) reported that they had not talked to their primary care physician at all about their options for AAA repair, and one-half (50%) reported that their view of the different surgical options had not been influenced by anyone. Slightly less than one-half of patients reported that they did not receive any information about open surgical aneurysm repair and endovascular aortic aneurysm repair (41% and 37%, respectively). Few patients indicated using the internet as their main source of information about open surgical aneurysm repair and endovascular aortic aneurysm repair (10% and 11%, respectively).

CONCLUSIONS

Patients are commonly referred for AAA repair having little to no information regarding AAA pathology or repair options. Fewer than one in five patients searched the internet or had accessed other sources of information on their own. Most vascular surgeons should assume that patients will present to their first vascular surgery appointment with minimal understanding of the treatment options available to them.

Incisional Hernia Following Open Abdominal Aortic Aneurysm Repair: A Contemporary Review of Risk Factors and Prevention

While the endovascular approach has been the treatment of choice for abdominal aortic aneurysm (AAA) repair in the modern era, open AAA repair remains a treatment option and may have a resurgence after the recent release of draft guidelines from the National Institute for Health and Care Excellence (NICE). Incisional hernia is a common long-term complication of open AAA repair and causes significant patient morbidity. As the number of patients undergoing open AAA repair increases, it is imperative that vascular surgeons are aware of and aim to reduce the complications associated with open surgery. This article summarises current evidence, highlighting the risk factors for incisional hernia and the modern surgical techniques that can prevent complications.

Assessment of Pull-out Forces in TEVAR and ANACONDA FEVAR Combination and Early Clinical Results: Creation of a Proximal Landing Zone for FEVAR in Patients with Extent I and Extent IV TAAAs

BACKGROUND

Although recent data on the treatment of thoracoabdominal aortic aneurysms (TAAAs) are promising, in some cases, the paravisceral segment of the aorta may not be suitable for a branched endograft due to space restrictions. A combination of a fenestrated aneurysm repair (FEVAR) with a thoracic aneurysm repair (TEVAR) may represent a feasible treatment option. The current investigation was performed to assess the stability of a fenestrated Anaconda device implanted into a set of thoracic endografts from different manufacturers. We then assessed our clinical results with the FEVAR/TEVAR combination.

METHODS

Pull-out forces were measured in vitro after docking a fenestrated Anaconda graft within the distal end of different TEVAR devices. Anaconda devices were implanted in 28- or 30-mm thoracic tube grafts (oversizing of at least 2 mm: 13.3-21.4; minimum overlap of 15 mm). Continuously increasing longitudinal pull forces of up to 100 N were applied on an Instron Tensile Tester. Initial break point and damage to the endografts were documented. Clinical results of patients treated with such an FEVAR/TEVAR combination at our institution are presented as a second part of this study.

RESULTS

Median pull-out forces ranged from 2.38 N to 55.0 N. The highest stability was achieved with 34-mm Anaconda devices in 28-mm thoracic tube grafts. Grafts with either thinner Dacron material or those featuring a polytetrafluorethylene membrane seemed especially vulnerable to punctures and tears caused by the downward-looking hooks of the Anaconda device. Between April 1, 2013 and December 31, 2018, in 28 of 172 patients treated with a fenestrated Anaconda device, prior implantation of a thoracic tube graft was necessary to create a sufficient proximal landing zone. In 25 cases (89.3%), the aneurysm was successfully treated. Although the 30-day reintervention rate in this subgroup was relatively high at 28.6%, none of these was due to a failure of the FEVAR/TEVAR combination. Upon an average follow-up of 15 months, no failure of the graft connection and no type III endoleak due to membrane damage were observed.

CONCLUSIONS

The combination of a thoracic tube graft and a fenestrated Anaconda device is a viable option for the treatment of patients with Extent I or IV TAAAs with no adequate landing zone above the celiac trunk. Although pull-out testing has shown good stability with most assessed grafts, the thoracic devices with thicker Dacron membranes seemed to be especially suitable.

Ten Years of Urgent Care of Ruptured Abdominal Aortic Aneurysms in a High-Volume-Center

BACKGROUND

The urgent treatment of ruptured abdominal aortic aneurysms (rAAA) remains a challenging condition with devastating morbidity and mortality. Available studies are often limited due to a significant selection bias. This study aims to illuminate real-world evidence using comprehensive data from electronic health records, registries, postmortem findings, and administrative data on all consecutively treated patients presenting with rAAA at a tertiary care center.

METHODS

This is a retrospective cross-sectional cohort study covering consecutively treated patients with rAAA between 2009 and 2018. All noninvasive treatments, fatalities, and invasive repairs were included. Information on patient's characteristics, prehospital, and inpatient care was gathered. Short-term outcomes and long-term survival were analyzed for relevant subgroups.

RESULTS

In total, 139 patients with rAAA (median age 75 years and 20.9% females, 79.9% infrarenal) were treated increasingly frequent by endovascular aortic repair (EVAR) when compared to open-surgical aortic repair (OSR) during the study period (16.7% in 2009 to 33.3% in 2018, P < 0.05). The rate of patients who had been turned down for rAAA repair was 10.8%, and the overall in-hospital mortality was 43.2%. Perioperative morbidity and mortality were similar for EVAR and OSR, although patients treated by OSR presented with a lower mean Glasgow Coma Scale during the prehospital (12.7 vs. 14.3) and inpatient care (12.7 vs. 14.4) (both P < 0.001), higher rates of intubation (12.8% vs. 10.9%, P < 0.001), lower systolic blood pressure (115 mm Hg vs. 127 mm Hg, P = 0.042), and more often had a cardiac arrest before the operation (14.1% vs. 2.3%, P < 0.001). Higher patient's age (Odds Ratio, OR 1.09; Hazard Ratio, HR 1.06), history of stroke or transient ischemic attack (OR 5.30; HR 2.64), higher serum creatinine (OR 1.81; HR 1.31), and occurrence of colonic ischemia (OR 11.31; HR 2.82) were significantly associated with higher odds of dying in hospital and in the longer term, respectively.

CONCLUSIONS

We observed comparable outcomes following OSR and EVAR, although hemodynamically unstable patients were more likely to be treated by OSR. This study also confirmed the impact of colonic ischemia as a devastating complication following rAAA repair emphasizing the need for further reflection by the vascular community.

Juxtarenal Abdominal Aortic Aneurysm: Results of Open Surgery in an Academic Center

BACKGROUND

The objective of the study is to report our experience with conventional surgery for juxtarenal abdominal aortic aneurysms (JRAs) by evaluating incidence of acute renal failure and perioperative mortality. Secondary objectives are to evaluate general morbidity and the need for permanent postoperative dialysis and to assess the influence on long-term survival of preoperative risk factors and deterioration of perioperative renal function.

METHODS

A retrospective cohort study of 110 patients with JRA electively treated by open surgery between March 1992 and March 2018 was made. Data were obtained from clinical records, describing demographics, perioperative variables, and results. Acute kidney injury (AKI) was defined as 50% decrease in glomerular filtration rate or two-fold increase in serum creatinine. Multivariate analysis was performed by logistic regression to establish risk factors for renal failure. The influence of preoperative risk factors and deterioration of perioperative renal function on long-term survival was studied using Cox regression model. Descriptive and inferential statistics were used in the analysis.

RESULTS

110 consecutive patients were treated with an average age of 71 years, 82.7% male; 81% hypertensive and 41% active smokers. 46.3% had stage III or higher preoperative chronic kidney disease. Median diameter of the aneurysm was 5.7 cm. Interruption of bilateral renal flow was required in 73 patients (66.4%) and unilateral in 37 (33.6%). The average renal clamping time was 34.5 min. AKI occurred in 9 patients (8.2%). Two patients (1.8%) required postoperative dialysis, one of them permanent. Median hospital stay was 7 days. Thirty-three patients (30%) had at least one complication. Postoperative mortality was 2.7% (3 patients), two of them developed AKI. Multivariate analysis established a longer operative time and need for renal revascularization as independent risk factors for AKI. In the survival analysis, age, cerebrovascular disease, chronic obstructive pulmonary disease, and perioperative AKI were identified as risk factors for long-term mortality.

CONCLUSIONS

JRA open surgical repair can be performed with low morbidity and mortality. Although transient acute renal dysfunction may be relatively frequent, the need for hemodialysis is low. Our study is a reference point to compare with endovascular repair.

Minimally Invasive Open Conversion for Late EVAR Failure

OBJECTIVE

With the increasing use of endovascular aortic aneurysm repair (EVAR), open repair after aortic stent grafting is of growing interest. The surgical conversion treatment may be a very challenging process with high mortality and in-hospital complication rates. The aim of this article is to present our experience in patients with EVAR failure treated by minimally invasive open conversion (MOC) and its technical aspects.

METHODS

A retrospective study was conducted on a prospectively compiled computerized database of consecutive patients treated by MOC at our institution between May 2014 and June 2018. Indications for treatment were endoleaks with sac growth at least >5 mm in the last 6 months and failure of previous endovascular tentative for aneurysm sealing. Demographics of the patients, reason for conversion, previous endovascular procedures, surgical outcomes, and survival were reviewed. MOC was performed by a small abdominal incision, infrarenal clamping, and partial explantation of the endograft in all patients.

RESULTS

A total of 10 patients were treated during the study period. The mean interval to MOC after EVAR was 45.1 months (range, 14-128). Indications for MOC included type Ia endoleak in three patients (30%), persistent type II EL in four (40%), and type III EL in one patient (10%), indeterminate or type V EL in two (20%). At 30 days, no deaths or reinterventions were reported, and major complication rate was 10% (one postoperative pneumonia). At mean follow-up of 22.9 ± 15.9 months, no reinterventions were described. Death rate was (20%) with one aneurysm-related death (10%) for graft infection 32 months after MOC and one (10%) cardiac event at 18 months.

CONCLUSIONS

Despite the potential high risk of open conversion, MOC appears to be a safe surgical solution for EVAR failure. This potentially challenging operation may be improved with minimally invasive techniques that are presented.

Effect of Endovascular Treatment Rate on Population Level Outcomes and Survival After Intact Abdominal Aortic Aneurysm Repair

OBJECTIVES

The aim was to study outcomes of endovascular aneurysm repair (EVAR) and open surgical repair (OSR) of abdominal aortic aneurysms (AAAs) in four geographically adjacent populations with identical demographics and variable EVAR rates.

METHODS

This was a multicentre cohort study based on local and national registry data from an area of 815 000 inhabitants. The study involved 527 consecutive patients with an intact AAA treated with EVAR (n = 327) or OSR (n = 200) between 2010 and 2016. The catchment area was divided into four health care districts (populations A, B, C, and D) with one central hospital in each district. Each hospital decided independently between OSR and EVAR for patients within their population; OSR was performed in all hospitals while EVAR was centralised in one of them. Patient demographics and treatment outcomes were extracted from local registries. Population demographics, overall AAA incidence, and mortality data were retrieved from a national database.

RESULTS

The rate of new intact AAA diagnosis varied between 20 and 29 per 100 000 inhabitants/year with the highest incidence in population D (p < .001). The intact AAA repair rates were 9.8, 8.9, 9.9, and 8.7 per 100 000 inhabitants/year for populations A, B, C, and D, respectively (p = .64). There were no significant differences in mean age (73.6 ± 8.0 years) or mean aortic diameter (62 ± 13 mm) between the treated patient populations. Groups A and B had high EVAR rates (74% and 72%, respectively) whereas the EVAR rates were lower in groups C and D (50% and 38%, respectively) (p < .001). The 30 day mortality rates were 2%, 2%, 4%, and 1% (p = .55), and complication rates were 17%, 12%, 15%, and 11% (p = .39) for A, B, C and D, respectively. There were no significant differences in mortality, complication or re-intervention rates between the groups during the mean follow up of 3.3 ± 2.0 years.

CONCLUSIONS

At population level, high EVAR rates had no measurable effect compared with lower EVAR rates on the outcomes in patients with intact AAA.

Disparities in Contemporary Treatment Rates of Abdominal Aortic Aneurysms Across Western Countries

OBJECTIVE/BACKGROUND

Several abdominal aortic aneurysm (AAA) screening programs have demonstrated a similar prevalence of this disease in Westerns countries, ranging from 1.2% to 2.8%. However, the annual rate of AAA repair is significantly less even, and its relationship to AAA prevalence is not clear. The objective was to perform a systematic review, describing an international overview in the yearly rate of AAA repairs.

METHODS

The number of elective and emergency AAA repairs was obtained via thorough review of publications indexed in PubMed and Scopus from 2010 to October 2018. Portuguese data were obtained from the national administrative database of health care. Data from the UK were extracted from the National Vascular Registry's 2015 annual report. Each country's population was assessed from published national censuses, thus allowing estimation of the number of AAAs treated per 100,000 habitants.

RESULTS

Data from 14 countries were obtained. The yearly number of elective operations per 100,000 habitants was 2.2 in Hungary, 3.8 in Portugal, 5.3 in Spain, 5.9 in Iceland, 6.5 in Finland, 7.0 in New Zealand, 7.8 in the UK, 10.0 in Denmark, 10.2 in Sweden, 13.3 in the USA, 14.8 in Norway, 15.3 in the Netherlands, 15.6 in Italy, and 17.3 in Germany. The yearly rate of ruptured repairs was 0.5 in Hungary, 1.5 in Portugal, 1.8 in Spain, 1.7 in Iceland, 1.7 in Finland, 1.3 in New Zealand, 1.8 in the UK, 3.3 in Denmark (2013), 2.7 in Sweden (2013), 1.7 in the USA, 2.1 in Norway, 3.1 in the Netherlands, 2.3 in Italy, and 2.7 in Germany.

CONCLUSION

The rate of AAA treatment is highly variable, with a nearly eightfold variance between the countries with the highest and lowest rates of elective repair. Correlation between elective and ruptured repairs was not clear. A deeper understanding of the reasons for the disparities in AAA treatment among Western countries is of the utmost importance.

Surgical publication activity in the English literature over a 10-year interval

Background

Surgical publication activity in the English literature over a 10-year interval may have changed. This study sought to identify which countries make the most contributions and whether significant shifts have occurred in this time.

Methods

Screening of 17 international journals in PubMed was performed for the time periods 2006-2007 and 2016-2017, for papers published by a first author belonging to a general surgical department. Data were collected by country regarding the total number of publications, cumulative impact factors (IFs), publications per inhabitant, IFs per inhabitant, and number of RCTs, meta-analyses and systematic reviews per country in both periods.

Results

A total of 2247 and 3029 papers were found for 2006-2007 and 2016-2017 respectively. In 2006-2007, most papers (605, 26·9 per cent; 2697·3 IFs) came from the USA, followed by Japan (284, 12·6 per cent; 1042·1 IFs) and the UK (197, 8·8 per cent; 923·1 IFs). In 2016-2017, the USA led again with 898 papers (29·6 per cent; 4575·3 IFs), followed by Japan with 414 papers (13·7 per cent; 1556·6 IFs) and the Netherlands with 167 (5·5 per cent; 885·2 IFs). From the top 15 countries, Sweden, the Netherlands and Switzerland contributed the most articles per inhabitant during both time periods. During both periods, the UK published the most RCTs, meta-analyses and systematic reviews.

Conclusion

Surgeons from the USA were the most productive in total number of publications during both time periods. However, smaller European countries were more active than the USA in relation to their population size.

Interaction between frailty and sex on mortality after elective abdominal aortic aneurysm repair

BACKGROUND

Controversy exists surrounding gender outcome disparity and abdominal aortic aneurysm (AAA) repair. Previous reports have demonstrated worse outcomes for women undergoing open aneurysm repair (OAR); however, these differences are less evident with endovascular aneurysm repair (EVAR). Epidemiologic studies have documented that women score higher on most frailty assessment scales but paradoxically have longer life expectancy compared to men. The interaction of gender/frailty and the influence on outcomes and practice patterns surrounding EVAR and OAR is poorly described. This analysis characterizes the association of frailty/sex interactions on mortality as well as patient selection surrounding elective AAA repair in the Society for Vascular Surgery Vascular Quality Initiative.

METHODS

All elective infrarenal AAA (EVAR + OAR; 2003-2017) cases were queried from the Vascular Quality Initiative database. Each patient was assigned a previously published modified frailty index (mFI) score derived from comorbidity and preoperative functional status data. Cox proportional hazard models, adjusted for statistically significant covariates, including procedural complexity, determined associations within full models and sex-stratified models.

RESULTS

A total of 20,750 elective AAA cases were analyzed (EVAR 15,893 [77%]; OAR 4857 [23%]). Thirty-day mortality for EVAR and OAR was 0.7% (n = 115) and 3.5% (n = 169), respectively. Patients who died were significantly more likely to be older (EVAR, 78 vs 73 years; OAR, 74 vs 69 years; P < .0001), have larger AAA diameters (EVAR, 59 vs 56 mm; P = .005; OAR, 62 vs 59 mm; P = .001), higher mFI scores (EVAR, 3.2 vs 2.4; OAR, 3.1 vs 2.2; P < .0001), and be of female sex (EVAR hazard ratio = 1.66 [95% confidence interval, 1.10-2.52]; P = .007; OAR-1.43 [1.02-1.99]; P = .003). Significant differences in the gender distribution of frailty scores among EVAR patients were evident (mean mFI: male 2.42 vs female 2.34; P = .02), but no difference was detected for OAR (male 2.17 vs female 2.22; P = .38). The mFI was a strong independent predictor of mortality (30 days: EVAR hazard ratio = 1.36 [1.22-1.53] and OAR 1.46 [1.32-1.60]; 1 year: EVAR 1.32 [1.25-1.39] and OAR-1.38 [1.28-1.48]). There was no interaction between mFI and gender on the association with mortality. Across frailty strata, male patients were nearly twofold more likely to undergo either elective EVAR or OAR for an AAA below recommended minimum diameter thresholds (male, <5.5 cm; female, <5.0 cm). Greater mFI score did not alter OAR selection but was associated with less frequent EVAR of small AAA.

CONCLUSIONS

Given the strong association between frailty and postoperative mortality, mFI can be used as a predictive tool to aid in surgical planning of patients undergoing elective AAA repair. While mFI can predict postoperative mortality for both men and women, it does not account for the survival disparity between sexes, and further research is warranted to explain this difference. There appear to be significant gender differences in patient selection based on current Society for Vascular Surgery-endorsed treatment thresholds that may have important implications on the appropriateness of AAA care delivery nationally.

Predictors of bleeding or anemia requiring transfusion in complex endovascular aortic repair and its impact on outcomes in health insurance claims

OBJECTIVE

This study aimed to determine predictors and outcomes associated with bleeding or anemia requiring transfusion (BAT) after fenestrated or branched endovascular aneurysm repair (FB-EVAR).

METHODS

Health insurance claims data of Germany's third largest insurance provider, DAK-Gesundheit, were used to investigate BAT in elective FB-EVAR performed between 2008 and 2017. International Classification of Diseases and German Operations and Procedure Key codes were used.

RESULTS

A total of 959 patients (24.8% with BAT) matching the inclusion criteria were identified during the study period. Compared with patients without BAT, patients with BAT were older (74.4 vs 73.0 years; P = .015) and suffered more frequently from congestive heart failure (18.5% vs 9.4%), cardiac arrhythmias (26.9% vs 14.7%), and hereditary or acquired coagulopathy (31.9% vs 6.2%; all P < .001). Coagulopathy (odds ratio [OR], 3.65; 95% confidence interval [CI], 2.29-5.84), female sex (OR, 2.67; 95% CI, 1.78-4.00), and multiple comorbidities (OR, 1.10; 95% CI, 1.07-1.14) were independent predictors of BAT (all P < .001). BAT was associated with higher in-hospital (11.3% vs 2.6%), 30-day (12.2% vs 3.1%), and 90-day (18.5% vs 4.4%) mortality (all P < .001). Furthermore, myocardial infarction (23.9% vs 2.8%) and paraplegia (9.7% vs 0.7%) were more frequent in the BAT group (all P < .001). In multivariable analyses, BAT was associated with worse short-term (OR, 3.19; 95% CI, 1.63-6.33; P = .001) and long-term survival (hazard ratio, 1.62; 95% CI, 1.24-2.11; P < .001).

CONCLUSIONS

Patients with hereditary or acquired coagulopathy, patients with multiple comorbidities, and women are at higher risk for development of BAT after FB-EVAR. The occurrence of this event was strongly associated with higher major complication rates and worse short-term and long-term survival. This emphasizes a need to further illuminate the value of patient blood management in FB-EVAR.

Variation in the choice of elective surgical procedure for abdominal aortic aneurysm in Spain

Objective

The two main surgical treatments for abdominal aortic aneurysm (AAA) are open surgical repair (OSR) and endovascular aneurysm repair (EVAR). The aim of this study was to analyze variation among Spanish hospitals in the use of OSR or EVAR for AAA. A secondary aim was to assess changes in preferences for these two procedures over time.

Methods

This was a retrospective longitudinal study based on discharge data from public hospitals in Spain during 2002–2012. Patient inclusion criteria were: age >18 years, elective admission, primary diagnosis of unruptured AAA, and surgical treatment with OSR or EVAR. The characteristics of the treating center, patients, and in-hospital mortality were recorded.

Results

We included 16,737 patients from 114 hospitals; 6,809 (40.7%) underwent EVAR and 9,928 (59.3%) underwent OSR. The total volume of surgeries increased throughout the period, and the probability that any given procedure was EVAR increased by 20% per year (OR 1.20, P<0.001). The volume and distribution of the two procedures varied highly across the participating hospitals. Overall, in-hospital mortality rate was 3.6% and it decreased during the study period (5.3% in 2002 and 3.2% in 2012), mainly due to a decrease in OSR-related mortality, despite a slight increase in EVAR-related mortality. Hospitals with higher surgical volumes were more likely to use EVAR and have lower in-hospital mortality rates.

Conclusion

This study reveals high variability in the surgical treatment of unruptured AAA across Spanish hospitals. The number of interventions has increased in recent years, with EVAR accounting for a growing percentage of these surgical procedures. Overall in-hospital mortality rates decreased significantly during this period, mainly due to lower mortality among patients undergoing OSR. In-hospital mortality rates were lower in higher-volume centers, regardless of the surgical approach used. Further research on variability and appropriateness of surgical management of AAA is required to assess the suitability of concentrating elective AAA repair in more experienced centers to potentially achieve better outcomes.

GRADE-Based Recommendations for Surgical Repair of Nonruptured Abdominal Aortic Aneurysm

The objective of this study was to provide evidence-based recommendations for endovascular aneurysm repair (EVAR) versus open surgical repair (OSR) for patients with a nonruptured abdominal aortic aneurysm (AAA). We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement and adhered to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework. Both low- and high surgical risk patients treated with EVAR showed decreased 30-day mortality, but the low-risk group had no differences in 4-year mortality. Compared with friendly anatomy, patients with hostile anatomy had an increased risk of type I endoleak. Young patients may prefer OSR. Endovascular aneurysm repair was not cost-effective in Europe. Four conditional recommendations were formulated: (1) OSR for low-risk patients up to 80 years old, (2) EVAR for low-risk patients older than 80 years, (3) EVAR for high-risk patients as long as is anatomically feasible, and (4) OSR in patients in whom it is not anatomically feasible to perform EVAR. Based on GRADE criteria, either OSR or EVAR can be suggested to patients with nonruptured AAA taking into account their surgical risk, hostile anatomy, and age. Given the weakness of the recommendations, personal preferences are determinant.

Predictors of in-hospital adverse events after endovascular aortic aneurysm repair

BACKGROUND

Endovascular aneurysm repair (EVAR) offered outstanding survival benefit but at the expense of cost, periodic radiographic monitoring, and higher reinterventions rates. Perioperative complications, although rare, can occur after EVAR, contributing to longer hospitalization, higher cost, and significant comorbidity and mortality. Therefore, the aim of this study was to identify the predictors of in-hospital events (IHEs) after elective EVAR.

METHODS

The Vascular Quality Initiative database was explored from 2003 to 2017. Patients who had converted to open repair were excluded. IHEs were defined as any in-hospital myocardial infarction, dysrhythmia, congestive heart failure (CHF), stroke, pneumonia, respiratory failure, renal failure, lower extremity ischemia, bowel ischemia, or reoperation. Stepwise backward selection based on the Akaike information criterion statistic was implemented to select the predictors of IHE from the multivariable logistic regression models. Bootstrapping was performed with 1000 replications to internally validate the model and to obtain bias-corrected estimates. Receiver operating characteristic curves (area under the curve [AUC]) and Hosmer-Lemeshow tests were used to assess the discrimination and calibration of the models.

RESULTS

A total of 28,240 patients with full information about IHEs were included. Any IHE took place in 2365 (8.4%) patients. Patients who had an IHE were slightly older (mean age ± standard deviation, 75.6 ± 8.1 years vs 73.3 ± 8.5 years; P < .001]. A higher proportion of women had an IHE (25.6% vs 17.9%; P < .001). Comorbid conditions were more prevalent in patients who developed an IHE (chronic kidney disease, 49.1% vs 33.2%; coronary artery disease, 34.3% vs 29.0%; moderate to severe CHF, 3.9% vs 1.4%; chronic obstructive pulmonary disease, 42.5% vs 31.9%; hypertension, 87.0% vs 83.1%; and diabetes, 18.0% vs 16.1%; all P ≤ .015). An IHE was associated with high in-hospital (5.6% vs 0.03%) and 30-day mortality (6.3% vs 0.3%; both P < .001) and worse 3-year survival beyond the perioperative period (81.1% [79.3%-82.9%] vs 91.1% [90.7%-91.5%]; P < .001). Two models were constructed, one from preoperative factors and the second from preoperative and intraoperative factors. The selected predictors of IHEs were female sex, moderate or severe CHF, chronic kidney disease, coronary artery disease, chronic obstructive pulmonary disease, hypertension, and aneurysm diameter. Intraoperative factors were contrast material volume, operative time, and packed red blood cell transfusion. Nomograms were constructed from the final models. AUC significantly improved after adding intraoperative factors (AUC [95% confidence interval], 0.71 [0.70-0.73] vs 0.65 [0.64-0.66]; P < .001].

CONCLUSIONS

In-hospital adverse events can complicate the perioperative course of EVAR and increase the risk of operative and long-term mortality. Predicting IHEs and identifying their risk factors can potentially mitigate their development in patients at high risk. Predicting IHE risk can have tremendous prognostic value and help disposition planning. This study introduces an internally validated tool to enable vascular surgeons to identify patients' chance of having an IHE.

The state of complex endovascular abdominal aortic aneurysm repairs in the Vascular Quality Initiative

BACKGROUND

Endovascular repair of complex abdominal aortic aneurysms has become increasingly common, but reports have mostly been limited to single centers and single devices.

METHODS

We studied all endovascular repairs of complex abdominal aortic aneurysms (zone 6 or caudal) from 2014 to 2018 in the Vascular Quality Initiative. This included all commercially available fenestrated endovascular aneurysm repair (FEVAR), chimney/snorkel repairs, and physician-modified endografts (PMEGs), exclusive of investigational device exemptions and clinical trial devices. We used inverse probability-weighted multilevel logistic regression to compare rates of perioperative outcomes including death, acute kidney injury (AKI), and major adverse cardiac events (MACEs; the composite of death/stroke/myocardial infarction) and Cox regression for long-term mortality.

RESULTS

During the study period, surgeons performed 1396 complex endovascular repairs: 1308 (94%) elective, 63 (4.5%) for symptomatic aneurysms, and 25 (1.8%) for rupture. The number of centers performing complex endovascular repairs expanded steadily from 39 in 2014 to 81 in 2017. There were 880 FEVAR (63%), 256 PMEG (18%), and 260 chimney/snorkel repairs (19%). In elective cases, 3214 visceral vessels were incorporated and revascularized; 120 repairs (9%) involved one vessel, 481 (38%) repairs involved two vessels, 560 (44%) involved three vessels, and 113 (9%) involved four vessels. The mean number of arteries incorporated was 2.5 ± 0.8, with PMEGs involving the most arteries (3.3 ± 0.8 for PMEG vs 2.5 ± 0.6 for FEVAR and 1.9 ± 0.9 for chimney/snorkel; P < .001). PMEGs were used to treat more extensive aneurysms, and more incorporated the celiac and superior mesenteric arteries. There was no change in aneurysm extent, but the length of proximal seal extended over time. Chimney/snorkel cases employed more arm or neck access, had longer procedure times, and used more contrast material. Rates of perioperative death (3.4% for FEVAR vs 2.7% for PMEG vs 6.1% for chimney/snorkel; P = .13) and AKI (17% vs 18% vs 19%; P = .42) were similar, but chimney/snorkel was associated with higher rates of stroke (0.8% vs 0.9% vs 3.3%; P = .03) and MACEs (6.1% vs 5.4% vs 11.7%; P = .02). After adjustment, rates of perioperative death, AKI, and overall complications remained similar, but chimney/snorkel was associated with significantly higher odds of stroke (odds ratio [OR], 7.3 [1.5-36.4]; P = .015), myocardial infarction (OR, 18.7 [2.6-136.8]; P = .004), and MACEs (OR, 11.1 [2.1-58.9]; P = .005). Overall survival after elective repair was 91% at 1 year and 88% at 3 years, with no difference between repair types in crude or adjusted analysis.

CONCLUSIONS

The Vascular Quality Initiative provides a unique opportunity to study the real-world application and outcomes of complex endovascular aneurysm repair. Perioperative morbidity appears to be higher after chimney/snorkel repair, but further study is needed to confirm these findings and to establish the durability of these novel technologies.

Outcomes of endovascular treatment of endoleak type Ia after EVAR: a systematic review of the literature

INTRODUCTION

Endovascular repair of infra-renal aortic aneurysm (EVAR) has become treatment of choice. However, individuals undergoing EVAR have a high re-intervention rate. The aim of this study is to evaluate the current endovascular treatment modalities of endoleak type Ia (ET Ia) treatment after EVAR and their outcome.

EVIDENCE ACQUISITION

A systematic review and meta-analysis was performed. MEDLINE, EMBASE and Cochrane databases were searched with PRISMA methodology for studies reporting on endovascular treatment of ET Ia after EVAR. Studies presenting treatment of intra-operative ET Ia were excluded.

EVIDENCE SYNTHESIS

Two international registries, fourteen non-randomized retrospective and twelve case-report studies were included reporting on 356 patients. Reported endovascular techniques included fenestrated-, branched-, chimney EVAR, endovascular sealing (EVAS), endoanchors, embolization techniques, cuff and/or "giant" Palmaz stents. Technical success rate ranged from 90% to 100%, with intra-operative mortality rate of 0%. During early period, persistence of ET Ia was 3.4% (9/262) and the re-intervention rate was 3.5% (8/227). The 30-day mortality rate was 2% (7/356). Mean follow-up was 22.4 months±18. Presence of ET Ia was 5.9% (21/356), and the reintervention rate was 5.1% (18/349). The mortality rate was 13% (26/203), while the primary patency rate of TVs ranged from 94.3% to 100%.

CONCLUSIONS

A multitude of techniques for endovascular repair for ET Ia exists. No strong evidence supports one specific technique. The early and mid-term outcomes are encouraging in terms of ET Ia resolution, mortality and morbidity rates.

Correlations Between Branch Vessel Catheterization and Procedural Complexity in Fenestrated and Branched Endovascular Aneurysm Repair

Introduction:

The use of fenestrated and branched endovascular technologies in complex aortic aneurysm repair (F/BEVAR) is increasing, with a trend toward using longer sealing zones and incorporating more target vessels. Successful aneurysm exclusion and prevention of long-term treatment failure need to be balanced against the increased complexity of more extensive procedures. The aim of this study was to analyze relationships between the number of catheterized vessels and multiple operative variables as a means for evaluating procedural complexity.

Methods:

Operative data from consecutive F/BEVAR procedures performed at a single center from 2012 to 2015 were analyzed. An equal number of EVAR procedures, randomly selected, from this period were also analyzed. Only intact aneurysms were included. Complex aneurysms were grouped based on the required number of target vessel catheterization. Ten procedural variables, categorized as perioperative, postoperative, and radiologic-related, were compared. Pearson correlation analysis and regression analysis were performed. The correlation coefficients, r, were classified using Cohen boundaries, r ≥ 0.5 indicating a strong relationship.

Results:

There were 63 EVAR, 40 FEVAR, and 22 BEVAR procedures. There was no significant difference in patient comorbidities between conventional EVAR and complex procedure groups. The complex procedures included 23 two-vessel, 20 three-vessel, and 19 four-vessel catheterizations. Strong linear relationships between the number of branch vessel catheterizations and the following variables were identified: accumulated skin dose ( r = .504), contrast volume ( r = .652), fluoroscopy duration ( r = .598), number of angiography series ( r = .650), anesthesiology duration ( r = .742), procedure duration ( r = .554), and total length of stay ( r = .533).

Conclusion:

The complexity of FEVAR and BEVAR procedures reveals strong correlations between multiple peri- and postoperative variables. These exposures and risks should be borne in mind when considering treatment of complex abdominal aortic aneurysms as well as long-term clinical outcomes.

Episode-based cost reduction for endovascular aneurysm repair

OBJECTIVE

Effective strategies to reduce costs associated with endovascular aneurysm repair (EVAR) remain elusive for many medical centers. In this study, targeted interventions to reduce inpatient EVAR costs were identified and implemented.

METHODS

From June 2015 to February 2016, we analyzed the EVAR practice at a high-volume academic medical center to identify, to rank, and ultimately to reduce procedure-related costs. In this analysis, per-patient direct costs to the hospital were compared before (September 2013-May 2015) and after (March 2016-January 2017) interventions were implemented. Improvement efforts concentrated on three categories that accounted for a majority of costs: implants, rooming costs, and computed tomography scans performed during the index hospitalization.

RESULTS

Costs were compared between 141 EVAR procedures before implementation (PRE period) and 47 EVAR procedures after implementation (POST period). Based on data obtained through the Society for Vascular Surgery EVAR Cost Demonstration Project, it was determined that implantable device costs were higher than those at peer institutions. New purchasing strategies were implemented, resulting in a 30.8% decrease in per-case device costs between the PRE and POST periods. Care pathways were modified to reduce use of and costs for computed tomography scans obtained during the index hospitalization. Compared with baseline, per-case imaging costs decreased by 92.9% (P < .001), including a 99.0% (P = .001) reduction in postprocessing costs. Care pathways were also implemented to reduce preprocedural rooming for patients traveling long distances the day before surgery, resulting in a 50% decrease in utilization rate (35.4% PRE to 17.0% POST; P = .021), without having a significant impact on median postprocedural length of stay (PRE, 2 days [interquartile range, 1-11 days]; POST, 2 days [1-7 days]; P = .185). Medication costs also decreased by 38.2% (P < .001) as a hospital-wide effort.

CONCLUSIONS

Excessive costs associated with EVAR threaten the sustainability of these procedures in health care organizations. Targeted cost reduction efforts can effectively reduce expenses without compromising quality or limiting patients' access.

Simulation training streamlines the real-life performance in endovascular repair of ruptured abdominal aortic aneurysms

OBJECTIVE

Difficulties in distributing endovascular experience among all operating room (OR) personnel prevented full-scale use of endovascular aneurysm repair (EVAR) in emergencies. To streamline the procedure of EVAR for ruptured aneurysm (rEVAR) and to provide this method even to unstable patients, we initiated regular simulation training sessions.

METHODS

This is an observational study of 29 simulation sessions performed between January 2015 and December 2017. We analyzed the development of time from OR door to aortic balloon occlusion during simulations and OR door to needle times in real-life rEVARs as well as the outcome of the 185 ruptured abdominal aortic aneurysm (rAAA) patients who arrived at the university hospital between January 2013 and December 2017. A questionnaire was sent for simulation attendants before and after the simulation session.

RESULTS

In the first simulations, the door to occlusion time was 20 to 35 minutes. After adding a hemodynamic collapse to the simulation protocol, the time decreased to 10 to 13 minutes in the 10 recent simulations, including a 5-minute cardiopulmonary resuscitation (P = .01). The electronic questionnaire performed for attendees before and after the simulation session showed significant improvement in both confidence and knowledge of the OR staff regarding rEVAR procedure. In the real-life rEVARs, 75 of the 185 patients with rAAAs underwent EVAR. Among rEVAR patients, the median OR door to needle time was 65 minutes before and 16 minutes after the onset of simulations (P = .000). The overall 30-day mortality among all rAAA patients was 44.8% and 30.6% accordingly (P = .046). When patients who were turned down from the emergency surgery were excluded, the 30-day operative mortality was 39.2% and 25.1% during the periods, respectively (P = .051). The 30-day mortality was 16.2% after rEVAR and 40.6% after open surgery (P = .001).

CONCLUSIONS

Simulation training for rEVAR significantly improves the treatment process in real-life patients and may enhance the outcome of rAAA patients.

Incidence, Treatment and Mortality in Patients with Abdominal Aortic Aneurysms

BACKGROUND

Aim of this study was to analyze hospital incidence, type of treatment, and hospital mortality rates of patients with abdominal aortic aneurysm (AAA) in Germany from 2005 to 2014.

METHODS

Microdata of the diagnosis-related group (DRG) statistics compiled by the German Federal Statistical Office for the years 2005-2014 were analyzed. Patients who were hospitalized for a ruptured AAA (rAAA, ICD-10 code I71.3, treated either surgically or conservatively) or received surgical treatment for an unruptured AAA (nrAAA, ICD-10-Code I71.4, treated either with open surgery or an endovascular procedure) were included in the analysis. The "European Standard Population 2013" was used for direct standardization of the hospital incidences. In-hospital mortality was calculated with standardization for age and risk.

RESULTS

The standardized overall hospital incidence of AAA was 27.9 and 3.3 cases per 100 000 people for men and women, respectively; over the period of the study, the incidence of rAAA fell by 30% in both sexes and that of nrAAA rose by 16% in men and 42% in women. The percentage of patients receiving endovascular treatment rose from 29% to 75% in patients with nrAAA and from 8% to 36% in patients with rAAA. The age- and risk-standardized in-hospital mortality of nrAAA was 3.3% in men and 5.3% in women. The in-hospital mortality of surgically treated rAAA was 39% in men and 48% in women.

CONCLUSION

The hospital incidence of AAA rose from 2005 to 2014, while that of rAAA fell. Endovascular treatment became more common for nrAAA as well as rAAA, and in-hospital mortality fell for both.

Prospective assessment of health-related quality of life after endovascular repair of pararenal and thoracoabdominal aortic aneurysms using fenestrated-branched endografts

OBJECTIVE

The objective of this study was to investigate changes in health-related quality of life (QOL) in patients treated for pararenal aortic aneurysms (PAAs) and thoracoabdominal aortic aneurysms (TAAAs) with fenestrated-branched endovascular aneurysm repair (F-BEVAR).

METHODS

A total of 159 consecutive patients (70% male; mean age, 75 ± 7 years) were enrolled in a prospective, nonrandomized single-center study using manufactured F-BEVAR (2013-2016). All patients were observed for at least 12 months (mean follow-up time, 27 ± 12 months). Patients' health-related QOL was assessed using the 36-Item Short Form Health Survey questionnaire at baseline (N = 159), 6 to 8 weeks (n = 136), 6 months (n = 129), and 12 months (n = 123). Physical component scores (PCSs) and mental component scores (MCSs) were compared with historical results of patients enrolled in the endovascular aneurysm repair (EVAR) 1 trial who were treated by standard EVAR for simple infrarenal abdominal aortic aneurysms.

RESULTS

There were 57 patients with PAAs and 102 patients with TAAAs (50 extent IV and 52 extent I-III TAAAs). There were no 30-day deaths, in-hospital deaths, conversions to open surgery, or aorta-related deaths. Survival was 96% at 1 year and 87% at 2 years. Major adverse events occurred in 18% of patients, and 1-year reintervention rate was 14%. There were no statistically significant differences between the groups in 30-day outcomes. Patients treated for TAAAs had lower baseline scores compared with those treated for PAAs (P < .05). PCS declined significantly 6 to 8 weeks after F-BEVAR in both groups and returned to baseline values at 12 months in the PAA group but not in the TAAA group. Patients with TAAAs had significantly lower PCSs at 12 months compared with those with PAAs (P < .001). There was no decline in mean MCS. Major adverse events were associated with decline in PCS assessed at 6 to 8 weeks (P = .021) but not in the subsequent evaluations. Reinterventions had no effect on PCS or MCS. Overall, patients treated by F-BEVAR had similar changes in QOL measures as those who underwent standard EVAR in the EVAR 1 trial, except for lower PCS in TAAA patients at 12 months.

CONCLUSIONS

Patients treated for TAAAs had lower scores at baseline in their physical aspect of health-related QOL. F-BEVAR was associated with significant decline in PCSs in both groups, which improved after 2 months and returned to baseline values at 12 months in patients with PAAs but not in those with TAAAs. Patients treated for PAAs had similar changes in QOL compared with those treated for infrarenal aortic aneurysms with standard EVAR.

Abdominal aortic aneurysms

An abdominal aortic aneurysm (AAA) is a localized dilatation of the infrarenal aorta. AAA is a multifactorial disease, and genetic and environmental factors play a part; smoking, male sex and a positive family history are the most important risk factors, and AAA is most common in men >65 years of age. AAA results from changes in the aortic wall structure, including thinning of the media and adventitia due to the loss of vascular smooth muscle cells and degradation of the extracellular matrix. If the mechanical stress of the blood pressure acting on the wall exceeds the wall strength, the AAA ruptures, causing life-threatening intra-abdominal haemorrhage - the mortality for patients with ruptured AAA is 65-85%. Although AAAs of any size can rupture, the risk of rupture increases with diameter. Intact AAAs are typically asymptomatic, and in settings where screening programmes with ultrasonography are not implemented, most cases are diagnosed incidentally. Modern functional imaging techniques (PET, CT and MRI) may help to assess rupture risk. Elective repair of AAA with open surgery or endovascular aortic repair (EVAR) should be considered to prevent AAA rupture, although the morbidity and mortality associated with both techniques remain non-negligible.

Treatment of aortic aneurysms registered in Swedvasc: Development reflected in a national vascular registry with an almost 100% coverage

Swedvasc is a registry for vascular surgical procedures, both open and endovascular. It was started in 1987 and since 1994 the whole population of Sweden is covered, at present around 10 million inhabitants. In a recent external validation, it was found to be highly accurate with abdominal aortic aneurysm surgery correctly reported in >96%. In this paper various factors explaining the almost 100% coverage are discussed, one important being that the registry has been developed and maintained within the profession of vascular surgery and not dictated by authorities. Another factor of importance is the possibility to use data in various research projects and so far 15 PhD theses have used Swedvasc data. To exemplify the practical use of the registry, the treatment of abdominal aortic aneurysms is scrutinized and among the various complications abdominal compartment syndrome is analyzed. Several significant temporal changes have been observed over the almost 25 years of Swedvasc: increasing use of endovascular surgery, treatment of aneurysms detected by screening , decreasing treatment for rupture, improved outcome, increasing treatment of older patients and patients with comorbid conditions. In conclusion, a high quality national vascular registry can be valid with high compliance and can be used to study population-based development of treatment and outcome. It can also be used to perform international comparisons with other registries, thereby getting an indication of the quality of care.