Editor's Choice - The Impact of Centralisation and Endovascular Aneurysm Repair on Treatment of Ruptured Abdominal Aortic Aneurysms Based on International Registries

A 20-Year Analysis of Ruptured Abdominal Aortic Aneurysm Outcomes and Associated Factors in Korea

BACKGROUND

Unlike western countries, which have reported distinct decreases in incidence of ruptured abdominal aortic aneurysm (rAAA) over the last few decades, epidemiologic studies in Korea have not shown significant changes in incidence or mortality of rAAA. The purpose of this study was to analyze the changes in rAAA treatment outcomes and various associated risk factors over the past 2 decades.

METHODS

A 20-year retrospective multicenter review for rAAA cases from the period of January 2000 to December 2020 was undertaken. Preoperative, intraoperative and postoperative clinical data were extracted for patients diagnosed with rAAA. For analysis, outcomes from the early era, defined as patients treated between January 1, 2000, and December 31, 2010, were compared with outcomes from the late era, defined as patients treated between January 1, 2011, and December 31, 2020.

RESULTS

The total in-hospital mortality was 34.1% in the early era compared to 44.8% in the late era. Patients in the late era were older than those in the early era (75.2 ± 10.3 years vs. 70.3 ± 8.9 years; P = 0.009). Treatment with rAAA endovascular aneurysm repair increased from 2.3% in early to 13.8% in late era (P = 0.031). In the early era, more patients were operated by experienced surgeons than the late era (78.1% vs. 45.9%; P = 0.002). The emergency room to operating room time did not show improvement over the 20 years.

CONCLUSIONS

The results indicate that mortality rate of rAAA in Korea has not changed over the last 2 decades. The study suggests the need for national preventive strategies, improved systemic coordination, and potential centralization of vascular services to enhance survival rates for rAAA.

[Recommendations for the specialist further training of nursing personnel on intensive care units in the treatment of abdominal aortic aneurysms: results of a modified Delphi procedure with experts]

INTRODUCTION

The medical development in the previous 15 years and the changes in treatment reality of the comprehensive elective treatment of abdominal aortic aneurysms necessitate a re-evaluation of the quality assurance guidelines of the Federal Joint Committee in Germany (QBAA-RL). In the current version this requires a specialist further training quota for nursing personnel in intensive care wards of 50%. The quota was determined in 2008 based on expert opinions, although a direct empirical evidence base for this does not exist.

METHODS

Representatives from the fields of patient representation, physicians, nursing personnel and other relevant interface areas were invited to participate in a modified Delphi procedure. Following a comprehensive narrative literature search, a survey and focus group discussions with national and international experts, a total of three anonymized online-based voting rounds were carried out for which previously determined key statements were assessed with a 4‑point Likert scale (totally disagree up to totally agree). In addition, the expert panel had also defined a recommendation for a minimum quota for the specialist training of nursing personnel on intensive care wards in the treatment of abdominal aortic aneurysms, whereby an a priori agreement of 80% of the participants was defined as the consensus limit.

RESULTS

Overall, 37 experts participated in the discussions and three successive voting rounds (participation rate 89%). The panel confirmed the necessity of a re-evaluation of the guideline recommendations and recommended the introduction of a shift-related minimum quota of 30% of the full-time equivalent of nursing personnel on intensive care wards and the introduction of structured promotional programs for long-term elevation of the quota.

CONCLUSION

In this national Delphi procedure with medical and nursing experts as well as representatives of patients, the fundamental benefits and needs of professional specialist qualifications in the field of intensive care medicine were confirmed. The corresponding minimum quota for specialist further training of intensive care nursing personnel should generally apply without limitations to specific groups. The expert panel stipulates a shift-related minimum quota for intensive care nursing personnel with specialist training of 30% of the nursing personnel on intensive care wards and the obligatory introduction of structured and transparent promotion programs for the long-term enhancement.

A Multidisciplinary Protocolized Approach for Ruptured Abdominal Aortic Aneurysm Management: A Retrospective Before-After Study

OBJECTIVES

To investigate whether implementation of a multidisciplinary protocol for ruptured abdominal aortic aneurysm (rAAA) management reduces rates of adverse complications.

DESIGN

A retrospective before-after study.

SETTING

A tertiary-care academic hospital.

PARTICIPANTS

Adult patients who underwent open or endovascular rAAA repair; data were stratified into before-protocol implementation (group 1: 2015-2018) and after-protocol implementation (group 2: 2019-2022) groups.

INTERVENTION

The protocol details the workflow for vascular surgery, anesthesia, emergency department, and operating room staff for a rAAA case; training was accomplished through yearly workshops.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was in-hospital mortality. Secondary outcomes included all-cause morbidity and other major complications. Differences in postoperative complication rates between groups were assessed using Pearson's χ2 test. Of the 77 patients included undergoing rAAA repair, 41 (53.2%) patients were in group 1, and 36 (46.8%) patients were in group 2. Patients in group 2 had a significantly shorter median time to incision (1.0 v 0.7 hours, p = 0.022) and total procedure time (180.0 v 160.5 minutes, p = 0.039) for both endovascular and open repair. After protocol implementation, patients undergoing endovascular repair exhibited significantly lower rates of mortality (46.2% v 20.0%, p = 0.048), all-cause morbidity (65.4% v 44.0%, p = 0.050), and renal complications (15.4% v 0.0%, p = 0.036); patients undergoing open repair for a rAAA exhibited significantly lower rates of mortality (53.3% v 27.3%, p = 0.018) and bowel ischemia (26.7% v 0.0%, p = 0.035).

CONCLUSIONS

Implementation of a multidisciplinary protocol for the management of a rAAA may reduce rates of adverse complications and improve the quality of care.

Hospital Volume of Elective Abdominal Aortic Aneurysm Repair as a Predictor of Mortality After Ruptured Abdominal Aortic Aneurysm Repair

OBJECTIVE

Registry data suggest that centralising abdominal aortic aneurysm (AAA) surgery decreases the mortality rate after AAA repair. However, the impact of higher elective volumes on ruptured AAA (rAAA) repair associated mortality rates remains uncertain. This study aimed to examine associations between intact AAA (iAAA) repair volume and post-operative rAAA death.

METHODS

Using data from official national registries between 2015 - 2019, all iAAA and rAAA repairs were separately analysed across 10 public hospitals. The following were assessed: 30 day and 12 month mortality rate following open surgical repair (OSR) and endovascular aneurysm repair (EVAR). Associations between the 5 year hospital iAAA repair volumes (organised into tertiles) and rAAA associated mortality rate were analysed, regardless of treatment modality. Receiver operating characteristic (ROC) curves were generated to identify iAAA volume thresholds for decreasing the rAAA mortality rate. Subanalysis by treatment type was conducted. Threshold analysis was repeated with the Markov chain Monte Carlo (MCMC) procedure to confirm the findings.

RESULTS

A total of 1 599 iAAAs (80.2% EVAR, 19.8% OSR) and 196 rAAAs (66.3% EVAR, 33.7% OSR) repairs were analysed. The median and interquartile range of the volume/hospital/year for all iAAA repairs were 39.2 (31.2, 47.4). The top volume iAAA tertile exhibited lower rAAA associated 30 day (odds ratio [OR] 0.374; p = .007) and 12 month (OR 0.264; p < .001) mortality rates. The ROC analysis revealed a threshold of 40 iAAA repairs/hospital/year (EVAR + OSR) for a reduced rAAA mortality rate. Middle volume hospitals for open iAAA repair had reduced 30 day (OR 0.267; p = .033) and 12 month (OR 0.223; p = .020) mortality rates, with a threshold of five OSR procedures/year. The MCMC procedure found similar thresholds. No significant association was found between elective EVAR volumes and ruptured EVAR mortality.

CONCLUSION

Higher iAAA repair volumes correlated with a lower rAAA mortality rate, particularly for OSR. The recommended iAAA repair threshold is 40 procedures/year and five procedures/year for OSR. These findings support high elective volumes for improving the rAAA mortality rate, especially for OSR.

The Role of Integrated Air Transport System in Managing Patients with Abdominal Aortic Aneurysm Rupture

OBJECTIVE

Ruptured abdominal aortic aneurysms (rAAAs) are highly morbid emergencies. Not all hospitals are equipped to repair them, and an air ambulance network may aid in regionalising specialty care to quaternary referral centres. The association between travel distance by air ambulance and rAAA mortality in patients transferred as an emergency for repair was examined.

METHODS

A retrospective review of institutional data. Adults with rAAA (2002 - 2019) transferred from an outside hospital (OSH) to a single quaternary referral centre for repair via air ambulance were identified. Patients who arrived via ground transport or post-repair at an OSH for continued critical care were excluded. Patients were divided into near and far groups based on the 75th percentile of the straight line travel distance (> 72 miles) between hospitals. The primary outcome was 30 day mortality. Multivariable logistic regression was used to assess the association between distance and mortality after adjusting for age, sex, race, cardiovascular comorbidities, and repair type.

RESULTS

A total of 290 patients with rAAA were transported a median distance of 40.4 miles (interquartile range 25.5, 72.7) with 215 (74.1%) near and 75 (25.9%) far patients. Both the near and far groups had similar ages, sex, and race. There was no difference in pre-operative loss of consciousness, intubation, or cardiac arrest between groups. Endovascular aneurysm repair utilisation and intra-operative aortic occlusion balloon use were also similar. Neither the observed (26.8% vs. 23.9%, p = .61) nor the adjusted odds ratio (0.70, 95% confidence interval 0.36 - 1.39, p = .32) 30 day mortality rate differed significantly between the near and far groups.

CONCLUSION

Increasing distance travelled during transfer by air ambulance was not associated with worse outcomes in patients with rAAA. The findings support the regionalisation of rAAA repair to large quaternary centres via an integrated and robust air ambulance network.

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

OBJECTIVE

To determine the peri-operative mortality rate for intact and ruptured abdominal aortic aneurysm (AAA) repair in 10 countries and to compare practice and outcomes over a six year period by age, sex, and geographic location.

METHODS

This VASCUNET study used prospectively collected data from vascular registries in 10 countries on primary repair of intact and ruptured AAAs undertaken between January 2014 and December 2019. The primary outcome was peri-operative death (30 day or in hospital). Logistic regression models were used to estimate the association between peri-operative death, patient characteristics, and type of procedure. Factors associated with the use of endovascular aortic aneurysm repair (EVAR) were also evaluated.

RESULTS

The analysis included 50 642 intact and 9 453 ruptured AAA repairs. The proportion of EVARs for intact repairs increased from 63.4% in 2014 to 67.3% in 2016 before falling to 62.3% in 2019 (p < .001), but practice varied between countries. EVAR procedures were more common among older patients (p < .001) and men (p < .001). Overall peri-operative mortality after intact AAA repair was 1.4% (95% confidence interval [CI] 1.3 - 1.5%) and did not change over time. Mortality rates were stable within countries. Among ruptured AAA repairs, the proportion of EVARs increased from 23.7% in 2014 to 35.2% in 2019 (p < .001). The average aortic diameter was 7.8 cm for men and 7.0 cm for women (p < .001). The overall peri-operative mortality rate was 31.3% (95% CI 30.4 - 32.2%); the rates were 36.0% (95% CI 34.9 - 37.2%) for open repair and 19.7% (95% CI 18.2 - 21.3%) for EVAR. This difference and shift to EVAR reduced peri-operative mortality from 32.6% (in 2014) to 28.7% (in 2019).

CONCLUSION

The international practice of intact AAA repair was associated with low mortality rates in registry reported data. There remains variation in the use of EVAR for intact AAAs across countries. Overall peri-operative mortality remains high after ruptured AAA, but an increased use of EVAR has reduced rates over time.

Editor's Choice -- European Society for Vascular Surgery (ESVS) 2024 Clinical Practice Guidelines on the Management of Abdominal Aorto-Iliac Artery Aneurysms

OBJECTIVE

The European Society for Vascular Surgery (ESVS) has developed clinical practice guidelines for the care of patients with aneurysms of the abdominal aorta and iliac arteries in succession to the 2011 and 2019 versions, with the aim of assisting physicians and patients in selecting the best management strategy.

METHODS

The guideline is based on scientific evidence completed with expert opinion on the matter. By summarising and evaluating the best available evidence, recommendations for the evaluation and treatment of patients have been formulated. The recommendations are graded according to a modified European Society of Cardiology grading system, where the strength (class) of each recommendation is graded from I to III and the letters A to C mark the level of evidence.

RESULTS

A total of 160 recommendations have been issued on the following topics: Service standards, including surgical volume and training; Epidemiology, diagnosis, and screening; Management of patients with small abdominal aortic aneurysm (AAA), including surveillance, cardiovascular risk reduction, and indication for repair; Elective AAA repair, including operative risk assessment, open and endovascular repair, and early complications; Ruptured and symptomatic AAA, including peri-operative management, such as permissive hypotension and use of aortic occlusion balloon, open and endovascular repair, and early complications, such as abdominal compartment syndrome and colonic ischaemia; Long term outcome and follow up after AAA repair, including graft infection, endoleaks and follow up routines; Management of complex AAA, including open and endovascular repair; Management of iliac artery aneurysm, including indication for repair and open and endovascular repair; and Miscellaneous aortic problems, including mycotic, inflammatory, and saccular aortic aneurysm. In addition, Shared decision making is being addressed, with supporting information for patients, and Unresolved issues are discussed.

CONCLUSION

The ESVS Clinical Practice Guidelines provide the most comprehensive, up to date, and unbiased advice to clinicians and patients on the management of abdominal aorto-iliac artery aneurysms.

The Role of Aortic Volume in the Natural History of Abdominal Aortic Aneurysms and Post-Endovascular Aortic Aneurysm Repair Surveillance

There has been a debate about whether maximum diameter can be solely used to assess the natural history of abdominal aortic aneurysm. The aim of the present review is to collect all the available evidence on the role of abdominal aortic aneurysm (AAA) volume in the natural history of AAAs, including small untreated AAAs and AAAs treated by EVAR. The current literature appears to reinforce the role of volume as a supplementary measure for evaluating the natural history of AAA, in both intact AAAs and after EVAR. The clinical impact of AAA volume measurements remains unclear. Several studies show that volumetric analysis can assess changes in AAAs and predict successful endoluminal exclusion after EVAR more accurately than diameter. However, most studies lack strict standardized measurement criteria and well-defined outcome definitions. It remains unclear whether volumetry could replace diameter assessment in defining the risk of rupture of AAAs and identifying clinically relevant sac growth.

Modern management of ruptured abdominal aortic aneurysm

Ruptured abdominal aortic aneurysms (rAAA) remain one of the most clinically challenging and technically complex emergencies in contemporary vascular surgery practice. Over the past 30 years, a variety of changes surrounding the treatment of rAAA have evolved including improvements in diagnosis, development of coordinated referral networks to transfer patients more efficiently to higher volume centers, deliberate de-escalation of pre-hospital resuscitation, modification of patient and procedure selection, implementation of clinical pathways, as well as enhanced awareness of certain high-impact postoperative complications. Despite these advances, current postoperative outcomes remain sobering since morbidity and mortality rates ranging from 25%-50% persist among modern published series. Some of the most impactful variation in rAAA management has been fostered by the rapid proliferation of endovascular repair (EVAR) along with service alignment at selected centers to improve timely revascularization. Indeed, clinical care pathways and emergency response networks are now increasingly utilized which has led to improved outcomes contemporaneously. Moreover, evolution in pre- and post-operative physiologic resuscitation has also contributed to observed improvements in rAAA outcomes. Due to different developments in care provision over time, the purpose of this review is to describe the modern management of rAAA, while providing historical perspectives on patient, procedure and systems-based practice elements that have evolved care delivery paradigms in this complex group of patients.

The Impact of Intra-Operative Heparin on Thromboembolism and Death in a Matched Cohort of Patients with a Ruptured Abdominal Aortic Aneurysm

Objective

Portuguese nationwide estimates indicate that 20% of abdominal aortic aneurysms (AAAs) are treated when ruptured. In these cases, intra-operative unfractionated heparin (UFH) usage rates vary widely. Evidence on this topic is scarce and focused on patients treated by open repair (OSR). The aim was to determine the influence of UFH on peri-operative thromboembolic events (TEs) and death in a cohort of ruptured AAA (rAAA).

Methods

Retrospective, single-centre, comparative study. From 2011 to April 2023, all consecutive rAAAs (endovascular repair [EVAR] and OSR) were considered. Primary outcomes were 30-day TE free survival and TE rates. The secondary outcome was 30-day death. Safety endpoints were procedural blood loss, blood product requirements, and secondary interventions due to haemorrhage. Using propensity score matching (PSM) each UFH patient was matched with one no UFH patient in a 1:1 ratio.

Results

The study included 250 patients. After PSM, 190 patients were analysed (EVAR: 60.0% no-UFH vs. 64.4% UFH). TE free survival estimates favoured the UFH group (67.3% vs. 47.2%, p = .009; UFH adjusted odds ratio [aOR] 2.01, 95% confidence interval [CI] 1.04-4.17). TEs were more frequent in the no UFH group (20.0% vs. 44.2% patients, p < .001; UFH aOR 0.31, 95% CI 0.15-0.65 for any TE), driven by an increase in bowel ischaemia (17.9% no UFH vs. 3.2% UFH, p = .001). Most events occurred in the first 72 hours. EVAR was associated with reduced TE and improved TE free survival (aOR 0.20, 95% CI 0.09-0.45 and aOR 5.54, 95% CI 2.34-13.08, respectively). No significant differences in 30-day survival were noted (75% no-UFH vs. 83% UFH, p = .26; aOR 1.08, 95% CI 0.48-2.43) nor in blood loss, peri-operative red blood cell and fresh frozen plasma requirements, or secondary interventions due to haemorrhage (p = .10; p = .11; p = .13 and p = .18 respectively).

Conclusion

In this cohort, intra-operative UFH was safe and associated with improved TE free survival, driven by a reduction in bowel ischaemia. Conversely, mortality remained unaffected. Randomised controlled trials are required to confirm these findings.

Type A aortic dissection: optimal annual case volume for surgery

BACKGROUND AND AIMS

The current study proposes a novel volume-outcome (V-O) meta-analytical approach to determine the optimal annual hospital case volume threshold for cardiovascular interventions in need of centralization. This novel method is applied to surgery for acute type A aortic dissection (ATAAD) as an illustrative example.

METHODS

A systematic search was applied to three electronic databases (1 January 2012 to 29 March 2023). The primary outcome was early mortality in relation to annual hospital case volume. Data were presented by volume quartiles (Qs). Restricted cubic splines were used to demonstrate the V-O relation, and the elbow method was applied to determine the optimal case volume. For clinical interpretation, numbers needed to treat (NNTs) were calculated.

RESULTS

One hundred and forty studies were included, comprising 38 276 patients. A significant non-linear V-O effect was observed (P < .001), with a notable between-quartile difference in early mortality rate [10.3% (Q4) vs. 16.2% (Q1)]. The optimal annual case volume was determined at 38 cases/year [95% confidence interval (CI) 37-40 cases/year, NNT to save a life in a centre with the optimal volume vs. 10 cases/year = 21]. More pronounced between-quartile survival differences were observed for long-term survival [10-year survival (Q4) 69% vs. (Q1) 51%, P < .01, adjusted hazard ratio 0.83, 95% CI 0.75-0.91 per quartile, NNT to save a life in a high-volume (Q4) vs. low-volume centre (Q1) = 6].

CONCLUSIONS

Using this novel approach, the optimal hospital case volume threshold was statistically determined. Centralization of ATAAD care to high-volume centres may lead to improved outcomes. This method can be applied to various other cardiovascular procedures requiring centralization.

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

OBJECTIVE

The need for open surgical conversion (OSC) after failed endovascular aortic aneurysm repair (EVAR) persists, despite expanding endovascular options for secondary intervention. The VASCUNExplanT project collected international data to identify risk factors for failed EVAR, as well as OSC outcomes. This retrospective cross sectional study analysed data after OSC for failed EVAR from the VASCUNET international collaboration.

METHODS

VASCUNET queried registries from its 28 member countries, and 17 collaborated with data from patients who underwent OSC (2005 - 2020). Any OSC for infection was excluded. Data included demographics, EVAR, and OSC procedural details, as well as post-operative mortality and complication rates.

RESULTS

There were 348 OSC patients from 17 centres, of whom 33 (9.4%) were women. There were 130 (37.4%) devices originally deployed outside of instructions for use. The most common indication for OSC was endoleak (n = 143, 41.1%); ruptures accounted for 17.2% of cases. The median time from EVAR to OSC was 48.6 months [IQR 29.7, 71.6]; median abdominal aortic aneurysm diameter at OSC was 70.5 mm [IQR 61, 82]. A total of 160 (45.6%) patients underwent one or more re-interventions prior to OSC, while 63 patients (18.1%) underwent more than one re-intervention (range 1 - 5). Overall, the 30 day mortality rate post-OSC was 11.8% (n = 41), 11.1% for men and 18.2% for women (p = .23). The 30 day mortality rate was 6.1% for elective cases, and 28.3% for ruptures (p < .0001). The predicted 90 day survival for the entire cohort was 88.3% (95% CI 84.3 - 91.3). Multivariable analysis revealed rupture (OR 4.23; 95% CI 2.05 - 8.75; p < .0001) and total graft explantation (OR 2.10; 95% CI 1.02 - 4.34; p = .04) as the only statistically significant predictive factors for 30 day death.

CONCLUSION

This multicentre analysis of patients who underwent OSC shows that, despite varying case mix and operative techniques, OSC is feasible but associated with significant morbidity and mortality rates, particularly when performed for rupture.

Outcomes of Elective and Non-elective Fenestrated-branched Endovascular Aortic Repair for Treatment of Thoracoabdominal Aortic Aneurysms

OBJECTIVE

To describe outcomes after elective and non-elective fenestrated-branched endovascular aortic repair (FB-EVAR) for thoracoabdominal aortic aneurysms (TAAAs).

BACKGROUND

FB-EVAR has been increasingly utilized to treat TAAAs; however, outcomes after non-elective versus elective repair are not well described.

METHODS

Clinical data of consecutive patients undergoing FB-EVAR for TAAAs at 24 centers (2006-2021) were reviewed. Endpoints including early mortality and major adverse events (MAEs), all-cause mortality, and aortic-related mortality (ARM), were analyzed and compared in patients who had non-elective versus elective repair.

RESULTS

A total of 2603 patients (69% males; mean age 72±10 year old) underwent FB-EVAR for TAAAs. Elective repair was performed in 2187 patients (84%) and non-elective repair in 416 patients [16%; 268 (64%) symptomatic, 148 (36%) ruptured]. Non-elective FB-EVAR was associated with higher early mortality (17% vs 5%, P <0.001) and rates of MAEs (34% vs 20%, P <0.001). Median follow-up was 15 months (interquartile range, 7-37 months). Survival and cumulative incidence of ARM at 3 years were both lower for non-elective versus elective patients (50±4% vs 70±1% and 21±3% vs 7±1%, P <0.001). On multivariable analysis, non-elective repair was associated with increased risk of all-cause mortality (hazard ratio, 1.92; 95% CI] 1.50-2.44; P <0.001) and ARM (hazard ratio, 2.43; 95% CI, 1.63-3.62; P <0.001).

CONCLUSIONS

Non-elective FB-EVAR of symptomatic or ruptured TAAAs is feasible, but carries higher incidence of early MAEs and increased all-cause mortality and ARM than elective repair. Long-term follow-up is warranted to justify the treatment.

Inter-Hospital Transfer of Patients With Ruptured Abdominal Aortic Aneurysm in Switzerland

OBJECTIVE

To analyse the association between inter-hospital transfer and hospital mortality in patients with ruptured abdominal aortic aneurysms (rAAA) in Switzerland.

METHODS

Secondary data analysis of case related hospital discharge data from the Swiss Federal Statistical Office for the years 2009 - 2018. All cases with rAAA as primary or secondary diagnosis were included. Cases with rAAA as a secondary diagnosis without surgical treatment and cases that had been transferred to another hospital without surgical treatment at the referring hospital were excluded. Logistic regression models for hospital mortality were constructed with age, sex, type of admission, van Walraven comorbidity score, type of treatment, insurance class, hospital level, and year of treatment as independent variables.

RESULTS

A total of 1 798 cases with rAAA were treated either surgically (62.5%) or palliatively (37.5%) in Switzerland from 1 January 2009 to 31 December 2018. Of these cases, 72.9% were treated directly (surgically or palliatively) at the hospital of first presentation, whereas 27.1% of all cases with rAAA were transferred between hospitals. The overall crude hospital mortality was 50.3%; being 23.1% in the surgically treated cohort and 95.7% in the palliatively treated cohort. Inter-hospital transfer was associated with better survival compared with patients who were admitted directly (OR 0.52; 95% CI 0.36 - 0.75; p < .001). Treatment in major hospitals was associated with significantly higher mortality rate compared with university hospitals (OR 1.98; 1.41 - 2.79; p < .001). There was no evidence of an association between open repair and hospital mortality (OR 1.06; 0.77 - 1.48; p = .72) compared with endovascular repair.

CONCLUSION

In a healthcare system such as Switzerland's with a highly specialised rescue chain, transfer of haemodynamically stable patients with rAAA is probably safe. In this setting, centralised medical care might outweigh the potential disadvantages of a short delay due to patient transfer. Further studies are needed to address potential confounding factors such as haemodynamic and anatomical features.

Is the Centralization of Complex Surgical Procedures an Unintended Spillover Effect of Global Capitation? - Insights from the Maryland Global Budget Revenue Program

OBJECTIVE

To determine if global budget revenue (GBR) models incent the centralization of complex surgical care.

SUMMARY BACKGROUND

In 2014, Maryland initiated a statewide GBR model. While prior research has shown improvements in cost and outcomes for surgical care post-GBR implementation, the mechanism remains unclear.

METHODS

Utilizing state inpatient databases, we compared the proportion of adults undergoing elective complex surgeries (gastrectomy, pneumonectomy/lobectomy, proctectomies, and hip/knee revision) at high-concentration hospitals (HCHs) in Maryland and control states. Annual concentration, per procedure, was defined as hospital volume divided by state volume. HCHs were defined as hospitals with a concentration at least at the 75 th percentile in 2010. We estimated the difference-in-differences (DiD) of the probability of patients undergoing surgery at HCHs before and after GBR implementation.

FINDINGS

Our sample included 122,882 surgeries. Following GBR implementation, all procedures were increasingly performed at HCHs in Maryland. States satisfied the parallel trends assumption for the centralization of gastrectomy and pneumonectomy/lobectomy. Post-GBR, patients were more likely to undergo gastrectomy (DiD: 5.5 p.p., 95% CI [2.2, 8.8]) and pneumonectomy/lobectomy (DiD: 12.4 p.p., 95% CI [10.0, 14.8]) at an HCH in Maryland compared with control states. For our hip/knee revision analyses, we assumed persistent counterfactuals and noted a positive DiD post-GBR implementation (DiD: 4.8 p.p., 95% CI [1.3, 8.2]). No conclusion could be drawn for proctectomy due to different pre-GBR trends.

CONCLUSIONS

GBR implementation is associated with increased centralization for certain complex surgeries. Future research is needed to explore the impact of centralization on patient experience and access.

Validation of I71.3 code for ruptured abdominal aortic aneurysm in Korea: misplaced diagnosis in claims data

Purpose

Studies in western countries have shown a decline in the incidence of ruptured abdominal aortic aneurysm (rAAA) with advancements in endovascular repair and screening. However, according to health insurance data in Korea based on rAAA code (I71.3), overall rAAA has been increasing. This study aimed to validate the I71.3 code for rAAA and attempt to define the true incidence of rAAA in Korea.

Methods

A 20-year multicenter retrospective review of rAAA was undertaken from the period of January 1, 2000 to December 31, 2020. All patients were diagnosed with the rAAA code I71.3 in each of the 4 hospitals. The CT images and surgical records of these patients were reviewed to differentiate true rAAA and misdiagnosis. Further data on true rAAA patient outcomes including mortality and treatment success were also collected.

Results

A total of 305 rAAA (I71.3) codes were identified in the 4 centers. However, medical record review showed true rAAA in only 131 (43.0%). The remaining 174 cases (57.0%) were misdiagnosed. Impending ruptures were the most common misdiagnoses (37.9%). The total in-hospital mortality including deaths before treatment was 38.9% (n = 51), while mortality of treated patients was 24.4% (n = 15).

Conclusion

The analysis of I71.3 code for rAAA showed that only 43.0% were true rAAA and the remaining 57.0% were misdiagnosed. This indicates that the I71.3 code is overestimated in National Health Insurance-based data and that the true incidence of rAAA could be much lower.

The Relationship Between Hospital Procedure Volume and Outcomes After Endovascular or Open Surgical Revascularisation for Peripheral Arterial Disease: An Analysis of Health Insurance Claims Data

OBJECTIVE

There is a paucity of data on the relationship between hospital procedure volume and outcomes after inpatient treatment of symptomatic peripheral arterial disease (PAD). This study aimed to generate meaningful hypotheses to support the ongoing discussion.

METHODS

Data derived from BARMER, Germany's second largest insurance provider, were linked with nationwide hospital procedure volumes from mandatory hospital quality reports. All endovascular (EVR) and open surgical revascularisations (OSR) provided to patients (≥ 40 years) with symptomatic PAD between 1 January 2013 and 31 December 2018 were included. Hospital volume was defined as the number of procedures performed by a hospital in the previous calendar year (in quartiles). Freedom from re-intervention, amputation, and overall mortality rate within 12 months after discharge were analysed using multivariable Cox proportional hazards models. In hospital mortality was determined by generalised estimating equations logistic regression models.

RESULTS

There were 88 187 revascularisations (72.4% EVR; EVR: 72.7 years and 45.2% females; OSR: 71.9 years and 41.9% females) registered by 668 hospitals. No statistically significant association was found between 12 month freedom from re-intervention and hospital volume (EVR: 4; quartile HR 1.05; 95% CI 0.94 - 1.16. OSR: 4; quartile HR 1.05; 95% CI 0.92 - 1.21). Patients with OSR had a decreased hazard of 12 month mortality in a high volume hospital compared with a low volume hospital (HR 0.85; 95% CI 0.73 - 0.98), but not with EVR (HR 1.03; 95% CI 0.91 - 1.16). Patients who were treated in hospitals with highest volumes showed decreased hazards of 12 month freedom from amputation when compared with low volume hospitals (EVR: HR 0.72; 95% CI 0.52 - 0.99. OSR: HR 0.61; 95% CI 0.44 - 0.85).

CONCLUSION

This large retrospective analysis of insurance claims suggests that higher procedure volume is associated with lower major amputation rates, although there is a need for standardisation of the definition of volume stratification. Future studies should address the impact of subsequent outpatient care and surveillance to further examine the complex interaction between treatment and outcomes.

Induction of CD73 prevents death after emergency open aortic surgery for a ruptured abdominal aortic aneurysm: a randomized, double-blind, placebo-controlled study

Mortality remains high after emergency open surgery for a ruptured abdominal aortic aneurysm (RAAA). The aim of the present study was to assess, if intravenous (IV) Interferon (IFN) beta-1a improve survival after surgery by up-regulating Cluster of differentiation (CD73). This is a multi-center phase II double-blind, 2:1 randomized, parallel group comparison of the efficacy and safety of IV IFN beta-1a vs. placebo for the prevention of death after open surgery for an infra-renal RAAA. All study patients presented a confirmed infra-renal RAAA, survived the primary emergency surgery and were treated with IFN beta-1a (10 μg) or matching placebo for 6 days after surgery. Major exclusion criteria included fatal hemorrhagic shock, chronic renal replacement therapy, diagnosed liver cirrhosis, severe congestive heart failure, advanced malignant disease, primary attempt of endovascular aortic repair (EVAR), and per-operative suprarenal clamping over 30 min. Main outcome measure was all-cause mortality at day 30 (D30) from initial emergency aortic reconstruction. The study was pre-maturely stopped due to a reported drug-drug interaction and was left under-powered. Out of 40 randomized patients 38 were included in the outcome analyses (27 IFN beta-1a and 11 placebo). There was no statistically significant difference between treatment groups at baseline except more open-abdomen and intestinal ischemia was present in the IFN beta-1a arm. D30 all-cause mortality was 22.2% (6/27) in the IFN beta-1a arm and 18.2% (2/11) in the placebo arm (OR 1.30; 95% CI 0.21-8.19). The most common adverse event relating to the IFN beta-1a was pyrexia (20.7% in the IFN beta-1a arm vs. 9.1% in the placebo arm). Patients with high level of serum CD73 associated with survival (P = 0.001) whereas the use of glucocorticoids and the presence of IFN beta-1a neutralizing antibodies associated with a poor CD73 response and survival. The initial aim of the trial, if postoperative INF beta-1a treatment results on better RAAA survival, could not be demonstrated. Nonetheless the anticipated target mechanism up-regulation of CD73 was associated with 100% survival. According to present results the INF beta-1a induced up-regulation of serum CD73 was blocked with both use of glucocorticoids and serum IFN beta-1a neutralizing antibodies. The study was pre-maturely stopped due to interim analysis after a study concerning the use if IV IFN beta-1a in ARDS suggested that the concomitant use of glucocorticoids and IFN beta-1a block the CD73 induction. Trial registration: ClinicalTrials.gov NCT03119701. Registered 19/04/2017 (retrospectively registered).

Screening for Abdominal Aortic Aneurysms and Risk Factors in 65-Year-Old Men in Oslo, Norway

Purpose

To investigate the prevalence of and risk factors for abdominal aortic aneurysm (AAA) in 65-year-old men in Oslo, Norway.

Materials and Methods

From May 2011, until September 2019, the annual population of 65-year-old men living in Oslo were invited to an ultrasonographic screening of the abdominal aorta. Candidates received a one-time invitation by mail, including a questionnaire on possible risk factors and comorbidities. Abdominal aortic outer-to-outer diameter and ankle-brachial index were measured by the screening team. Participants were allocated into three groups: non-, sub- and aneurysmal aorta. Written information on recommended follow-up regime was given to participants with an aortic diameter ≥25 mm. Univariate and multivariate analyses of potential risk factors were performed, in addition to descriptive analyses and significance testing.

Results

In total, 19,328 were invited, 13,215 men were screened, of which 12,822 accepted inclusion in the study. Aortic diameter was registered for 12,810 participants and 330 men had aortic diameter ≥30 mm, giving a prevalence of AAA of 2.6% (95% confidence interval (CI) 2.31-2.86). We identified 4 independent risk factors for AAA: smoking (OR = 3.64, 95% CI 2.90-4.58), hypertension (OR = 1.87, 95% CI 1.49-2.35), BMI >30 (OR = 1.02, 95% CI 1.00-1.03), and diabetes mellitus (OR = 0.52, 95% CI 0.35-0.79), the latter showing an inverse association with AAA growth. A subgroup of 862 men with aortic diameters 25-29 mm had a significantly higher prevalence of BMI >25, smoking and family history of AAA, compared to participants with aortic diameter <25 mm.

Conclusion

Among the participants in this study, the prevalence of abdominal aortic aneurysms was 2.6%. Participants with AAA more frequently reported cardiovascular risk factors, and less frequently diabetes mellitus.

Outcomes and predictors of mortality in a Belgian population of patients admitted with ruptured abdominal aortic aneurysm and treated by open repair in the contemporary era

BACKGROUND

Abdominal aortic aneurysm (AAA) rupture is a serious condition that results in extremely high mortality rates. Some improvements in outcome have been reported during the last 2 decades. The objective of the present study was to determine the overall and operative (by open repair) mortality related to ruptured AAA in the contemporary era and to identify preoperative, intraoperative, and early postoperative parameters associated with poor outcomes.

METHODS

We performed a retrospective review of all consecutive patients admitted to our single institution with a diagnosis of ruptured AAA between 2004 and 2013. A total of 103 parameters, including demographic characteristics, medical history, clinical and biological parameters, cardiovascular risk factors, emergency level, diagnostic modalities, time from symptoms to diagnosis and treatment, type of operative procedure and postoperative complications, were analyzed. The primary endpoint considered in this study was the cumulative incidence rate of mortality. The secondary endpoint was the identification, by logistic regression methods, of risk factors for overall mortality as well as for operative, and postoperative mortality.

RESULTS

Within our study period, 104 patients were admitted for a ruptured AAA. The majority of patients (84.6%) were male, and the AAA was known in 34.6% of the patients. Rupture occurred for a maximal diameter lower than 55 mm in 25% of the female population, compared to 5.7% of the male population (P = 0.030). The proportions of admitted patients who died before (preoperative mortality), during (intraoperative mortality) or after (postoperative hospital mortality) surgery was 17.3%, 16.3%, and 18.3%, respectively, yielding a cumulative in-hospital mortality of 51.9%. In the multivariate analysis, age ≥ 80 (P = 0.001), myocardial ischemia on the admission ECG (P = 0.046), and management by the physician response unit (P = 0.002) were the only preoperative parameters associated with a higher risk of hospital mortality. Four risk factors were found to be associated with a higher risk of postoperative mortality in the multivariate analysis, and all patients presenting with 3 or more of these risk factors (n = 5) died.

CONCLUSIONS

The overall mortality of ruptured AAA in a contemporary cohort of patients who underwent open repair remains high and does not seem to have decreased during recent decades. Ruptures occur at smaller diameters in women than in men, supporting a lower threshold for intervention in women with known AAA. We developed risk scores to predict the mortality of patients with rAAA at different times of their hospital course. The validity of these scores should be assessed in prospective clinical studies.

Editor's Choice - Systematic Review and Meta-Analysis of the Impact of Institutional and Surgeon Procedure Volume on Outcomes After Ruptured Abdominal Aortic Aneurysm Repair

OBJECTIVE

To investigate whether there is a correlation between institutional or surgeon case volume and outcomes in patients with ruptured abdominal aortic aneurysm (rAAA).

DATA SOURCES

The Healthcare Database Advanced Search interface developed by the National Institute of Health and Care Excellence was used to search MEDLINE, Embase, CINAHL, and CENTRAL.

REVIEW METHODS

The systematic review complied with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines with the protocol registered in PROSPERO (CRD42020213121). Prognostic studies were considered comparing outcomes of patients with rAAA undergoing repair in high and low volume institutions or by high and low volume surgeons. Pooled estimates for peri-operative mortality were calculated using the odds ratio (OR) and 95% confidence intervals (CI), applying the Mantel-Haenszel method. Analysis of adjusted outcome estimates was performed with the generic inverse variance method.

RESULTS

Thirteen studies reporting a total of 120 116 patients were included. Patients treated in low volume centres had a statistically significantly higher peri-operative mortality than those treated in high volume centres (OR 1.39; 95% CI 1.22 - 1.59). Subgroup analysis showed a mortality difference in favour of high volume centres for both endovascular aneurysm repair (EVAR; OR 1.61, 95% CI 1.11 - 2.35) and open repair (OR 1.50, 95% CI 1.25 - 1.81). Adjusted analysis showed a benefit of treatment in high volume centres for open repair (OR 1.68, 95% CI 1.21 - 2.33) but not for EVAR (OR 1.42, 95% CI 0.84 - 2.41). Differences in peri-operative mortality between low and high volume surgeons were not statistically significant for either EVAR (OR 1.06, 95% CI 0.59 - 1.89) or open surgical repair (OR 1.18, 95% CI 0.87 - 1.63).

CONCLUSION

A high institutional volume may result in a reduction of peri-operative mortality following surgery for rAAA. This peri-operative survival advantage is more pronounced for open surgery than EVAR. Individual surgeon caseload was not found to have a significant impact on outcomes.

Nationwide Study of Ruptured Abdominal Aortic Aneurysms During Twenty Years (1994-2013)

OBJECTIVE

To analyze the epidemiology of ruptured abdominal aortic aneurysms (RAAA) in Sweden over 20 years, and assess the effect of endovascular repair (EVAR) on surgical treatment rate and outcome.

METHODS

All Swedish citizens >50 years with RAAA 1994 to 2013 were extracted from 3 national (Cause of Death, Patient, and Vascular Surgical) registries. Incidence, proportion repaired, surgical techniques, and 90-day mortality were assessed based on sex and age groups, with regression analysis.

RESULTS

18,726 individuals with RAAA were identified, 74.0% men. The incidence of RAAA decreased from 33.1/100,000: 1994 to 21.3/100,000: 2013 (relative change -35.6%, P < 0.001). The proportion of men with RAAA undergoing repair was 44.5%: 1994-1998, 49.7%: 2009-2013 (+11.7%, P < 0.001). In women, 22.3% were repaired in 1994-1998, versus 28.2%: 2009-2013 (+26.4%, P < 0.001). The proportion undergoing repair increased in octogenarians (men: +44.3%, P < 0.001; women +49.3%, P = 0.001). EVAR increased from 0% initially to 42.3% in men and 41.2% in women 2013. Overall, mortality rate among all individuals with RAAA decreased, men 75.8%: 1994-1998, 64.8%: 2009-2013 (-14.5%, P < 0.001); women 88.5%: 1994-1998, 82.2%: 2009-2013 (-7.1%, P < 0.001). Among those who underwent repair, mortality was 47.0% in men: 1994-1998, 31.8%: 2009-2013 (-32.3%, P < 0.001); women 51.8%: 1994-1998, 41.4%: 2009-2013 (-20.1%, P = 0.010).

CONCLUSION

RAAA mortality among men decreased, mainly attributed to falling incidence of RAAA. The mortality was further reduced by more patients being offered repair, increasingly often with EVAR, and improved survival after repair. Incidence of rupture remained unchanged among women, who had higher RAAA mortality. Focused efforts to reduce RAAA mortality among women are warranted.

Association between Hospital Volume and Failure to Rescue after Open or Endovascular Repair of Intact Abdominal Aortic Aneurysms in the VASCUNET and International Consortium of Vascular Registries

OBJECTIVE

To investigate the association between hospital volume and failure to rescue (FtR), after open (OAR) and endovascular (EVAR) repair of intact abdominal aortic aneurysms (AAA) among centers participating in the VASCUNET and International Consortium of Vascular Registries (ICVR).

SUMMARY BACKGROUND DATA

FtR (i.e., in-hospital death following major complications) is a composite end-point representing the inability to treat complications effectively and prevent death.

METHODS

Using data from eight vascular registries, complication and mortality rates after intact AAA repair were examined (n = 60,273; EVAR-43,668; OAR-16,605). A restricted analysis using pooled data from four countries (Australia, Hungary, New Zealand, USA) reporting data on all postoperative complications (bleeding, stroke, cardiac, respiratory, renal, colonic ischemia) was performed to identify risk-adjusted association between hospital volume and FtR.

RESULTS

The most frequently reported complications were cardiac (EVAR-3.0%, OAR-8.9%) and respiratory (EVAR-1.0%, OAR-5.7%). In adjusted analysis, 4.3% of EVARs and 18.5% of OARs had at least one complication. The overall FtR rate was 10.3% after EVAR and 15.7% after OAR. Subjects treated in the highest volume centers(Q4) had 46% and 80% lower odds of FtR after EVAR (OR = 0.54; 95%CI = 0.34-0.87;p = 0.04) and OAR (OR = 0.22; 95%CI = 0.11-0.44;p < 0.001) when compared to lowest volume centers(Q1), respectively. Colonic ischemia had the highest risk of FtR for both procedures (adjusted predicted risks, EVAR: 27%, 95%CI 14%-45%; OAR: 30%, 95%CI 17%-46%).

CONCLUSIONS

In this multi-national dataset, FtR rate after intact AAA repair with EVAR and OAR is significantly associated with hospital volume. Hospitals in the top volume quartiles achieve the lowest mortality after a complication has occurred.

Outcomes of emergency endovascular versus open repair for abdominal aortic aneurysm rupture

Purpose

Ruptured abdominal aortic aneurysm (rAAA) is one of the most common aortic emergencies in vascular surgery and is associated with high operative mortality and morbidity rates despite recent treatment advances. We evaluated operative mortality risks for the outcomes of emergency endovascular aneurysm repair (eEVAR) vs. open repair in rAAA.

Methods

Twenty patients underwent eEVAR (n = 12) or open repair (n = 8) for rAAA between 2016 and 2020. We adopted the EVAR first strategy since 2018. Primary endpoints included in-hospital mortality and 1-year survival. The outcome variables were analyzed with Fisher exact, Mann-Whitney test, and linear by linear association. The Kaplan-Meier method was used to estimate survival.

Results

There were 13 males (65.0%) and the median age of the study cohort was 78.0 years (range, 49–88 years). In-hospital mortality occurred in 7 patients (35.0%); 5 (50.0%) in the early period and 2 (20.0%) in the later period of this series. According to the procedure type, 4 (50.0%) and 3 (25.0%) in-hospital mortalities occurred in the open repair and eEVAR patients, respectively. In 6 patients (50.0%), eEVAR was performed on unfavorable anatomy. The 1-year survival of eEVAR vs. open repair group was 75% ± 12.5% and 50% ± 17.7%, respectively. On univariate analysis, preoperative high-risk indices, postoperative acute renal failure requiring dialysis, pulmonary complications, and prolonged mechanical ventilation were associated with higher operative mortality.

Conclusion

The current data showed relatively superior outcomes with eEVAR vs. open repair for rAAA, even in some patients with unfavorable anatomy supporting the feasibility, efficacy, and safety of EVAR first strategy.

Outcomes of Vascular and Endovascular Interventions Performed During the Coronavirus Disease 2019 (COVID-19) Pandemic

OBJECTIVE

The aim of the COVER Study is to identify global outcomes and decision making for vascular procedures during the pandemic.

BACKGROUND DATA

During its initial peak, there were many reports of delays to vital surgery and the release of several guidelines advising later thresholds for vascular surgical intervention for key conditions.

METHODS

An international multi-center observational study of outcomes after open and endovascular interventions.

RESULTS

In an analysis of 1103 vascular intervention (57 centers in 19 countries), 71.6% were elective or scheduled procedures. Mean age was 67 ± 14 years (75.6% male). Suspected or confirmed COVID-19 infection was documented in 4.0%. Overall, in-hospital mortality was 11.0% [aortic interventions mortality 15.2% (23/151), amputations 12.1% (28/232), carotid interventions 10.7% (11/103), lower limb revascularisations 9.8% (51/521)]. Chronic obstructive pulmonary disease [odds ratio (OR) 2.02, 95% confidence interval (CI) 1.30-3.15] and active lower respiratory tract infection due to any cause (OR 24.94, 95% CI 12.57-241.70) ware associated with mortality, whereas elective or scheduled cases were lower risk (OR 0.4, 95% CI 0.22-0.73 and 0.60, 95% CI 0.45-0.98, respectively. After adjustment, antiplatelet (OR 0.503, 95% CI: 0.273-0.928) and oral anticoagulation (OR 0.411, 95% CI: 0.205-0.824) were linked to reduced risk of in-hospital mortality.

CONCLUSIONS

Mortality after vascular interventions during this period was unexpectedly high. Suspected or confirmed COVID-19 cases were uncommon. Therefore an alternative cause, for example, recommendations for delayed surgery, should be considered. The vascular community must anticipate longer term implications for survival.

Editor's Choice - Optimal Threshold for the Volume-Outcome Relationship After Open AAA Repair in the Endovascular Era: Analysis of the International Consortium of Vascular Registries

OBJECTIVE

As open abdominal aortic aneurysm (AAA) repair (OAR) rates decline in the endovascular era, the endorsement of minimum volume thresholds for OAR is increasingly controversial, as this may affect credentialing and training. The purpose of this analysis was to identify an optimal centre volume threshold that is associated with the most significant mortality reduction after OAR, and to determine how this reflects contemporary practice.

METHODS

This was an observational study of OARs performed in 11 countries (2010 - 2016) within the International Consortium of Vascular Registry database (n = 178 302). The primary endpoint was post-operative in hospital mortality. Two different methodologies (area under the receiving operating curve optimisation and Markov chain Monte Carlo procedure) were used to determine the optimal centre volume threshold associated with the most significant mortality improvement.

RESULTS

In total, 154 912 (86.9%) intact and 23 390 (13.1%) ruptured AAAs were analysed. The majority (63.1%; n = 112 557) underwent endovascular repair (EVAR) (OAR 36.9%; n = 65 745). A significant inverse relationship between increasing centre volume and lower peri-operative mortality after intact and ruptured OAR was evident (p < .001) but not with EVAR. An annual centre volume of between 13 and 16 procedures per year was associated with the most significant mortality reduction after intact OAR (adjusted predicted mortality < 13 procedures/year 4.6% [95% confidence interval 4.0% - 5.2%] vs. ≥ 13 procedures/year 3.1% [95% CI 2.8% - 3.5%]). With the increasing adoption of EVAR, the mean number of OARs per centre (intact + ruptured) decreased significantly (2010 - 2013 = 35.7; 2014 - 2016 = 29.8; p < .001). Only 23% of centres (n = 240/1 065) met the ≥ 13 procedures/year volume threshold, with significant variation between nations (Germany 11%; Denmark 100%).

CONCLUSION

An annual centre volume of 13 - 16 OARs per year is the optimal threshold associated with the greatest mortality risk reduction after treatment of intact AAA. However, in the current endovascular era, achieving this threshold requires significant re-organisation of OAR practice delivery in many countries, and would affect provision of non-elective aortic services. Low volume centres continuing to offer OAR should aim to achieve mortality results equivalent to the high volume institution benchmark, using validated data from quality registries to track outcomes.

Comparison between Totally Percutaneous Approach and Femoral Artery Cut-Down in Endovascular Aortic Repair of Ruptured Abdominal Aortic Aneurysms in a Single Hospital

PURPOSE

To evaluate the short-term outcome of totally percutaneous endovascular aortic repair (pEVAR) of ruptured abdominal aortic aneurysms (AAAs) compared with femoral cut-down endovascular aortic repair (cEVAR).

MATERIALS AND METHODS

The medical records of patients with ruptured AAAs that underwent EVAR between March 2010 and April 2017 were retrospectively reviewed. Demographic information, preoperative vital signs, preoperative laboratory data, method of anesthesia, procedure duration, aneurysm morphology, brand of device used, length of hospital stay, access complications, and short-term outcomes were recorded. Univariate as well as multivariate logistic regression was used to identify predictors of 30-day mortality.

RESULTS

Among 77 patients with ruptured AAAs, 17 (22.1%) received cEVAR and 60 (77.9%) received pEVAR. Significant differences in the procedure time (P = 0.004), method of anesthesia (P = 0.040), and 30-day mortality (P = 0.037) were detected between the cEVAR and pEVAR groups. Local anesthesia plus intravenous general anesthesia (odds ratio = 0.141, P = 0.018) was an independent factor associated with 30-day mortality and local anesthesia was better than general anesthesia for 24-hr mortality (P = 0.001) and 30-day mortality (P = 0.003).

CONCLUSION

In patients with ruptured AAAs, pEVAR procedures took less time than cEVAR procedures, but the length of hospital stay did not differ significantly. The 30-day mortality rate was lower with pEVAR than with cEVAR. Local anesthesia may be the key factor in EVAR to improved technical and clinical success.

Management of Descending Thoracic Aortic Diseases: Similarities and Differences Among Cardiovascular Guidelines

Cardiovascular societies have developed recommendations regarding the management of thoracic aortic diseases. While improvements in treatment have been observed during the past decade in regard to patient selection, thoracic endovascular aortic repair (TEVAR) and associated techniques, and high-volume centralization, the broad expansion of TEVAR has raised considerations about its indications, appropriateness, limitations, and application. The aim of this systematic review was to assess the similarities and differences among current cardiovascular societies' guidelines for the management of thoracic aortic diseases. The MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials were searched from January 2009 to May 2020. The initial search identified 990 articles. After exclusion of duplicate or inappropriate articles, the final analysis included 5 articles from cardiovascular societies published between 2010 and 2020. Selected controversial topics were analyzed, including diagnosis, imaging, spinal cord ischemia prevention, and management of the most important thoracic aortic pathologies. The analysis included data concerning the therapeutic approach in acute and chronic type B aortic dissection, penetrating aortic ulcer, intramural hematoma, thoracic aortic aneurysm, and traumatic aortic injury, as well a discussion of inflammatory aneurysms, aortitis, and genetic syndromes. The review presents consistent and controversial recommendations, as well as "gray zone" issues that need further investigation. There was significant overlap and agreement among the 5 societies regarding the management of thoracic aortic diseases. Especially in dissection and aneurysm management, TEVAR has established its role as the treatment of choice. However, robust evidence is still needed in many aspects of the management of thoracic aortic pathologies.

Female Sex and Outcomes after Endovascular Aneurysm Repair for Abdominal Aortic Aneurysm: A Propensity Score Matched Cohort Analysis

OBJECTIVE

Previous studies have showed a potential disadvantage of female patients who underwent abdominal aortic aneurysm (AAA) repair. The current study aims to determine sex-specific perioperative and long-term outcomes using propensity score matched unselected nationwide health insurance claims data.

METHODS

Insurance claims from a large German fund were used, covering around 8% of the insured German population. Patients who underwent endovascular aortic repair (EVAR) for intact AAA from 1 January 2011 to 30 April 2017 were included in the cohort. A 1:2 female to male propensity score matching was applied to adjust for confounding variables. Perioperative and long-term outcomes after 5 years were determined using matching and regression methods.

RESULTS

Among a total of 3736 patients (19.3% females, mean 75 years) undergoing EVAR for intact AAA, we identified 1863 matched patients. Before matching, females were more likely to be previously diagnosed with hypothyroidism, electrolyte disorders, rheumatoid disorders, and depression, while males were more often diabetics. In the matched sample, 23.4% of the females and 25.8% of the males died during a median follow-up of 776 and 792 days, respectively. Perioperatively, females were more likely to exhibit acute limb ischemia (5.3% vs. 3.2%, p = 0.031) and major bleeding (22.0% vs. 15.9%, p = 0.001) before they were discharged to rehabilitation (5.5% vs. 1.5%, p < 0.001) when compared to males. No statistically significant difference in perioperative (odds ratio 1.12, 95% CI 0.54-2.16) or long-term mortality (hazard ratio 0.91, 95% CI 0.76-1.08) was observed between sexes. This was also true regarding aortic reintervention rates after 1 year (2.0% vs. 2.9%) and 5 years (10.9% vs. 8.1%).

CONCLUSION

The current retrospective matched analysis of insurance claims revealed high early access-related morbidity in females when compared to their male counterparts. Short-term or long-term survival and reintervention outcomes were similar between sexes.

Management of Abdominal Aortic Aneurysm Disease: Similarities and Differences Among Cardiovascular Guidelines and NICE Guidance

The development of endovascular techniques has improved abdominal aortic aneurysm (AAA) management over the past 2 decades. Different cardiovascular societies worldwide have recommended the endovascular approach as the standard of care in their currently available guidelines. While endovascular treatment has established its role in daily clinical practice, a new debate has arisen regarding the indications, appropriateness, limitations, and role of open surgery. To inform this debate, the MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials databases were searched from 2010 to May 2020; the systematic search identified 5 articles published between 2011 and 2020 by 4 cardiovascular societies and the National Institute of Health and Care Excellence (NICE). Four debatable domains were assessed and analyzed: diagnostic methods and screening, preoperative management, indications and treatment modalities, and postoperative follow-up and endoleak management. The review addresses controversial proposals as well as widely accepted recommendations and "gray zone" issues that need to be further investigated and analyzed, such as screening in women, medical management, and follow-up imaging. While the recommendations for AAA management have significant overlap and agreement among international cardiovascular societies, the NICE guidelines diverge regarding the role of open repair in aortic disease, recommending conventional surgery in most elective cases.

Climatic influence on the risk of abdominal aortic aneurysm rupture

Our aim is to examine the effects of climatic conditions on the incidence of ruptured abdominal aortic aneurysms (rAAA) in Catalonia, Spain. We combined clinical data from the Public Health official registries in Catalonia, Spain (HD-MBDS) of all rAAA with local climatic data obtained from the closest meteorological station (69 stations, National Meteorological Service: MeteoCat) from 2008 to 2017. We analyzed the median, maximum, minimum, and variability of atmospheric pressure (hPa) and air temperature (°C), solar irradiation (MJ/m²), humidity (%), accumulated precipitation (mm), median wind, and maximum flaw direction and velocity (°, m/s), recorded on the days of events, the previous day, and mean results for 3, 7, and 30 days before, as well as seasonality. Seventy-five control days were randomly selected in a 1-year period around every rAAA day at the same meteorological station, and compared. A total of 717 days and locations with rAAA were identified, and 53,775 controls were randomly selected. For the rAAA days, there were significantly lower temperatures, lower solar global irradiation, and higher mean humidity levels in all time periods (p < 0.001, p < 0.001, p < 0.05); higher atmospheric pressure variability during 1 week and 1 month before (p = 0.011, p = 0.007); and they often occurred during autumn/winter (57.6%, p < 0.001). Logistic regression identified low mean temperatures on the days of ruptures and high mean humidity the week before as independent rupture predictors. In conclusion, low median temperatures the same day and high humidity during 1 week before were identified as independent predictors of rAAA occurrence. The role of climate on pathophysiologic mechanisms may require further investigation.

The Relationship Between Operative Volume and Peri-operative Mortality After Non-elective Aortic Aneurysm Repair in Australia

OBJECTIVE

Hospital and surgeon operative caseload is thought to be associated with peri-operative mortality following the non-elective repair of aortic aneurysms; however, whether such an association exists within the Australian healthcare setting is unknown.

METHODS

The Australasian Vascular Audit was interrogated to identify patients undergoing non-elective (emergency [EMG] or semi-urgent [URG]) aortic aneurysm repair between 2010 and 2016, as well as their treating surgeon and hospital. Hierarchal logistic regression modelling was used to assess the impact of caseload on outcomes after both endovascular (EVAR) and open surgical repair (OSR).

RESULTS

Volume counts were determined from 14 262 patients (4 121 OSR and 10 141 EVAR). After exclusion of elective procedures and duplicates, 1 153 EVAR (570 EMG and 583 URG) and 1 245 OSR (946 EMG and 299 URG) non-elective cases remained for the analysis. Crude mortality was 24.0% following OSR (EMG 29.2%; URG 7.7%) and 7.5% following EVAR (EMG 12.6%; URG 2.4%). Univariable analysis demonstrated an association between OSR mortality and hospital volume (quintile [Q] 1: 25.3%, Q2: 27.8%, Q3: 23.9%, Q4: 27.0%, Q5: 16.2%; p = .030), but not surgeon (Q1: 25.2%, Q2: 27.4%, Q3: 26.0%, Q4: 21.4%, Q5: 19.5%, p = .32). Multivariable analysis confirmed this association (odds ratio (OR) [95% CI]; Q1 vs 5: 1.91 [1.13-3.21], Q2 vs. 5: 2.01[1.24-3.25], Q3 vs. 5: 1.41 [0.86-2.29], Q4 vs. 5: 1.92 [1.17-3.15]; p = .020). The difference was most pronounced in the EMG OSR group [Q1 - 3 vs. 4-5] (OR 1.63 [1.07-2.48]; p = .020). Mortality after EVAR was not associated with either hospital (Q1: 6.3%, Q2: 10%, Q3: 6.8%, Q4: 4.5%, Q5: 10%; p = .14) or surgeon volume (Q1: 9.3%, Q2: 5.7%, Q3: 8.1%, Q4: 7.0%, Q5: 7.3%; p = .67).

CONCLUSION

There is an inverse correlation between hospital volume and peri-operative mortality following EMG open repair of aortic aneurysm. These data support restructuring Australian pathways of care to direct suspected ruptured aneurysm to institutions that reach a minimum volume threshold.

Paradigm shifts in abdominal aortic aneurysm management based on vascular registries

Abdominal aortic aneurysm (AAA) is a relatively common and potentially fatal disease. The management of AAA has undergone extensive changes in the last two decades. High quality vascular surgical registries were established early and have been found to be instrumental in the evaluation and monitoring of these changes, most notably the wide implementation of minimally invasive endovascular surgical technology. Trends over the years showed the increased use of endovascular aneurysm repair (EVAR) over open repair, the decreasing perioperative adverse outcomes and the early survival advantage of EVAR. Also, data from the early EVAR years changed the views on endoleak management and showed the importance of tracking the implementation of new techniques. Registry data complemented the randomized trials performed in aortic surgery by showing the high rate of laparotomy-related reinterventions after open repair. Also, they are an essential tool for the understanding of outcomes in a broad patient population, evaluating the generalizability of findings from randomized trials and analysing changes over time. By using large-scale data over longer periods of time, the importance of centralization of care to high-volume centres was shown, particularly for open repair. Additionally, large-scale databases can offer an opportunity to assess practice and outcomes in patient subgroups (e.g. treatment of AAA in women and the elderly) as well as in rare aortic pathologies. In this review article, we point out the most important paradigm shifts in AAA management based on vascular registry data.

Patients with a Ruptured Abdominal Aortic Aneurysm Are Better Informed in Hospitals with an "EVAR-preferred" Strategy: An Instrumental Variable Analysis of the Dutch Surgical Aneurysm Audit

BACKGROUND

While several observational studies suggested a lower postoperative mortality after minimal invasive endovascular aneurysm repair (EVAR) in patients with a ruptured abdominal aortic aneurysm (RAAA) compared to conventional open surgical repair (OSR), landmark randomized controlled trials have not been able to prove the superiority of EVAR over OSR. Randomized controlled trials contain a selected, homogeneous population, influencing external validity. Observational studies are biased and adjustment of confounders can be incomplete. Instrumental variable (IV) analysis (pseudorandomization) may help to answer the question if patients with an RAAA have lower postoperative mortality when undergoing EVAR compared to OSR.

METHODS

This is an observational study including all patients with an RAAA, registered in the Dutch Surgical Aneurysm Audit between 2013 and 2017. The risk difference (RD) in postoperative mortality (30 days/in-hospital) between patients undergoing EVAR and OSR was estimated, in which adjustment for confounding was performed in 3 ways: linear model adjusted for observed confounders, propensity score model (multivariable logistic regression analysis), and IV analysis (two-stage least square regression), adjusting for observed and unobserved confounders, with the variation in percentage of EVAR per hospital as the IV instrument.

RESULTS

2419 patients with an RAAA (1489 OSR and 930 EVAR) were included. Unadjusted postoperative mortality was 34.9% after OSR and 22.6% after EVAR (RD 12.3%, 95% CI 8.5-16%). The RD adjusted for observed confounders using linear regression analysis and propensity score analysis was, respectively, 12.3% (95% CI 9.6-16.7%) and 13.2% (95%CI 9.3-17.1%) in favor of EVAR. Using IV analysis, adjusting for observed and unobserved confounders, RD was 8.9% (95% CI -1.1-18.9%) in favor of EVAR.

CONCLUSIONS

Adjusting for observed confounders, patients with an RAAA undergoing EVAR had a significant better survival than OSR in a consecutive large cohort. Adjustment for unobserved confounders resulted in a clinical relevant RD. An "EVAR preference strategy" in patients with an RAAA could result in lower postoperative mortality.

Fenestrated repair improves perioperative outcomes but lacks a hospital volume association for complex abdominal aortic aneurysms

BACKGROUND

Complex abdominal aortic aneurysms (AAAs) have traditionally been treated with an open surgical repair (OSR). During the past decade, fenestrated endovascular aneurysm repair (FEVAR) has emerged as a viable option. Hospital procedural volume to outcome relationship for OSR of complex AAAs has been well established, but the impact of procedural volume on FEVAR outcomes remains undefined. This study investigated the outcomes of OSR and FEVAR for the treatment of complex AAAs and examined the hospital volume-outcome relationship for these procedures.

METHODS

A retrospective review of a statewide vascular surgery registry was queried for all patients between 2012 and 2018 who underwent elective repair of a juxtarenal/pararenal AAA with FEVAR or OSR. The primary outcomes were 30-day mortality, myocardial infarction, and new dialysis. Secondary end points included postoperative pneumonia, renal dysfunction (creatine concentration increase of >2 mg/dL from preoperative baseline), major bleeding, early procedural complications, length of stay, and need for reintervention. To evaluate procedural volume-outcomes relationship, hospitals were stratified into low- and high-volume aortic centers based on a FEVAR annual procedural volume. To account for baseline differences, we calculated propensity scores and employed inverse probability of treatment weighting in comparing outcomes between treatment groups.

RESULTS

A total of 589 patients underwent FEVAR (n = 186) or OSR (n = 403) for a complex AAA. After adjustment, OSR was associated with higher rates of 30-day mortality (10.7% vs 2.9%; P < .001) and need for dialysis (11.3% vs 1.8; P < .001). Postoperative pneumonia (6.8% vs 0.3%; P < .001) and need for transfusion (39.4% vs 10.4%; P < .001) were also significantly higher in the OSR cohort. The median length of stay for OSR and FEVAR was 9 days and 3 days, respectively. For those who underwent FEVAR, endoleaks were present in 12.1% of patients at 30 days and 6.1% of patients at 1 year, with the majority being type II. With a median follow-up period of 331 days (229-378 days), 1% of FEVAR patients required a secondary procedure, and there were no FEVAR conversions to an open aortic repair. Hospitals were divided into low- and high-volume aortic centers based on their annual FEVAR volume of complex AAAs. After adjustment, hospital FEVAR procedural volume was not associated with 30-day mortality or myocardial infarction.

CONCLUSIONS

FEVAR was associated with lower perioperative morbidity and mortality compared with OSR for the management of complex AAAs. Procedural FEVAR volume outcome analysis suggests limited differences in 30-day morbidity, although long-term durability warrants further research.

Altered IL-32 Signaling in Abdominal Aortic Aneurysm

INTRODUCTION AND OBJECTIVE

Interleukin (IL)-32 is a pro-inflammatory cytokine not previously studied in relation to abdominal aortic aneurysm (AAA). The aim of this study was to elucidate the expression and localization of IL-32 in AAA.

METHODS

Expression and localization of IL-32 in human aortic tissue was studied with immunohistochemical analysis and Western blot (AAA: n = 5; controls: n = 4). ELISA was used to measure IL-32 in human plasma samples (AAA: n = 140; controls: n = 37) and in media from cultured peripheral blood mononuclear cells (PBMCs) from 3 healthy donors. IL-32 mRNA in PBMCs, endothelial cells, aortic smooth muscle cells (SMCs), and aortic tissue samples of AAA (n = 16) and control aortas (n = 9) was measured with qPCR.

RESULTS

IL-32 was predominantly expressed in SMCs and T-cell-rich areas. Highest mRNA expression was observed in the intima/media layer of the AAA. A weaker protein expression was detected in non-aneurysmal aortas. Expression of IL-32 was confirmed in isolated T cells, macrophages, endothelial cells, and SMCs, where expression was also inducible by cytokines such as interferon-γ. There was no difference in IL-32 expression in plasma between patients and controls.

CONCLUSION

IL-32 signaling is altered locally in AAA and could potentially play an important role in aneurysm development. Further studies using animal models would be helpful to study its potential role in AAA disease.

Mortality from abdominal aortic aneurysm: trends in European Union 15+ countries from 1990 to 2017

BACKGROUND

This observational study assessed trends in abdominal aortic aneurysm (AAA) death rates in European Union (EU) 15+ countries for the years 1990 to 2017.

METHODS

Age-standardized death rates (ASDRs) were extracted from the Global Burden of Disease Study Global Health Data Exchange. Trends were analysed using joinpoint regression analysis.

RESULTS

Between 1990 and 2017, ASDRs from AAA decreased in all 19 EU15+ countries for women, and in 18 of 19 countries for men. Increasing AAA mortality was observed only for men in Greece (+5·3 per cent). The largest relative decreases in ASDR between 1990 and 2017 were observed in Australia (men -65·6 per cent, women -50·4 per cent) and Canada (men -60·8 per cent, women -48·6 per cent). Over the 28-year interval, the smallest decreases in ASDR for women were noted in Greece (-2·3 per cent) and in Italy (-2·5 per cent). In 2017, the highest mortality rates were observed in the UK for both men and women (7·5 per 100 000 and 3·7 per 100 000 respectively). The lowest ASDR was observed in Portugal for men (2·8 per 100 000) and in Spain for women (1·0 per 100 000). ASDRs for AAA in 2017 were higher for men than women in all 19 EU15+ countries. The most recent trends demonstrated increasing AAA ASDRs in 14 of 19 countries for both sexes; the increases were relatively small compared with the improvements in the preceding years.

CONCLUSION

This observational study identified decreasing mortality from AAA across EU15+ countries since 1990. The most recent trends demonstrated relatively small increases in AAA mortality across the majority of EU15+ countries since 2012.

Nationwide Analysis of Ruptured Abdominal Aortic Aneurysm in Portugal (2000-2015)

OBJECTIVE

Ruptured abdominal aortic aneurysm (rAAA) is a lethal condition that requires acute repair to prevent death. This analysis aims to assess the nationwide trends in rAAA admission, repair and mortality in a country, Portugal, without national screening for AAA.

METHODS

rAAA registered in the hospital administrative database of the National Health Service and all nationally registered deaths due to rAAA based on death certificate data were analysed. Three time periods (2000-2004, 2005-2009, and 2010-2015) were compared in patients ≥ 50 years old to assess the variations over time.

RESULTS

A total of 2 275 patients ≥50 years old with rAAA were identified in the two databases from 2000 to 2015. The age standardised incidence of rAAA was 2.78 ± 0.24/100 000/year in 2000-2004, 3.17 ± 0.39/100 000/year in 2005-2009 and 3.21 ± 0.28/100 000/year in 2010-2015 (p < .001). When comparing the time periods 2000-2004 to 2005-2009, the age standardised rate of admission (n = 1460) increased from 1.57 ± 0.25/100 000/year to 2.24 ± 0.32/100 000/year (p < .001). The operative mortality rates decreased during this time period (from 55.3 ± 4.7% to 48.8 ± 4.7%, p < .001). In 2010-2015, the age standardised rate of admissions due to rAAA decreased (1.98 ± 0.22/100 000/year). Operative mortality remained stable (48.9 ± 6.2%). The rate of patient deaths outside the hospital decreased from the first to the second period (1.21 ± 0.10/100 000/year and 0.93 ± 0.29/100 000/year, respectively) but later increased (1.14 ± 0.22/100 000/year). This resulted in a higher overall rAAA related mortality in Portugal in the third period (2.20 ± 0.18/100 000/year, 2.21 ± 0.27/100 000/year and 2.26 ± 0.26/100 000/year in 2000-2004, 2005-2009, and 2010-2015, respectively, p < .001).

CONCLUSION

Overall, the incidence of rAAA in Portugal has been stable over the past 10 years. The rates of admission, repair, and death due to rAAA repair seem to have reached an inflection point and are now decreasing. Mortality outside the hospital remains a matter of concern, warranting further planning of streamlined transfer networks and vascular surgical departments.

Impact of Centralisation on Abdominal Aortic Aneurysm Repair Outcomes: Early Experience in Catalonia

OBJECTIVE

Several studies have revealed high volume centres have better outcomes in the treatment of abdominal aortic aneurysms (AAAs), thus supporting centralisation of this procedure into selected centres based on volume. To date however, the real benefit of centralisation of this pathology has not been well demonstrated. The aim of this study was to analyse the impact of centralisation in to high volume centres (defined as those performing more than 30 cases per year) on AAA treatment outcomes carried out in Catalonia (Spain).

METHODS

Data were collected from official national registries (HDMBD) for AAA treated by endovascular aneurysm repair (EVAR) or open repair (OR) over a nine year period. Two time periods were selected for comparison: before centralisation (2009-2014) and after complete centralisation (2015-2017). The primary objective was to determine short term mortality (in hospital and 30 day mortality) and length of stay (LOS) after intact AAA (iAAA) and ruptured AAA (rAAA) repair, before and after centralisation. Uni- and multivariable analyses were performed in order to identify independent outcomes predictors.

RESULTS

A total of 3 501 iAAAs, including 1 124 (32.1%) OR and 2377 (67.9%) EVAR, and 409 rAAAs, including 218 (53.3%) OR and 191 (46.7%) EVAR, were identified. After centralisation, there was a significant decrease in overall mortality in iAAA repair (4.7% vs. 2.0%, p < .001) and rAAA repair (53.1% vs. 41.9%, p = .028). Mortality reduction in iAAAs was significant for OR (8.7% vs. 3.6%, p = .005), but not for EVAR (2.2% vs. 1.5%, p = .25). Overall LOS decreased as well, mainly in iAAAs (9.49 ± 10.84 vs. 7.44 ± 12.23 days, p < .001), and in particular in elective EVAR (7.32 ± 7.73 vs. 6.00 ± 8.97 days, p < .001). Multivariable analysis was identified before the centralisation period as an independent predictor for both mortality (odds ratio 1.484, 95% CI 1.098-2.005, p = .010) and LOS (B coefficient 1.146, 95% CI 0.218-2.073, p = .016).

CONCLUSION

The implementation of a country based centralisation programme for AAA treatment led to a significant reduction in short term mortality, for both iAAA and rAAA, and mainly for elective OR. LOS also significantly decreased, mainly for elective EVAR. These results support the benefit of centralisation of AAA repair procedures.

Anatomical Differences Between Intact and Ruptured Large Abdominal Aortic Aneurysms

Purpose: To compare different anatomical characteristics between intact and ruptured large abdominal aortic aneurysms (rAAA >80 mm) with the goal of refining the process of estimating rupture risk. Materials and Methods: A retrospective study involving 62 male patients with large (>80 mm) aneurysms matched for age and smoking produced a 31-patient elective group with a mean maximum aneurysm diameter of 92±9.7 mm and a 31-patient rAAA group (mean maximum aneurysm diameter 95.7±12 mm). Preoperative computed tomography angiography scans were analyzed with a dedicated workstation, and anatomical characteristics of the aortic neck, iliac arteries, and aneurysm were compared in multivariable regression analyses; the outcomes are given as the odds ratio (OR) with 95% confidence interval (CI). The prognostic utility of several characteristics as predictors of rupture occurrence was examined with receiver operating characteristic (ROC) curves. Results: Anatomical characteristics differing significantly between elective and ruptured aneurysms were the infrarenal aortic neck diameters at 5 mm, 10 mm and 15 mm; the neck length and calcification; the common iliac artery (CIA) lengths; the iliac artery indexes; the left CIA and external iliac artery diameters; and the total and true lumen aneurysm volumes. Intraluminal thrombus (ILT) volume did not differ (p=0.76), although its distribution in elective vs ruptured cases did [absent: 0% vs 19%, respectively (p=0.025); circumferential: 61% vs 35%, respectively (p=0.04)]. Total aneurysm volume was higher in rAAA (442±140 mL) vs intact AAA (331±143 mL, p=0.014), while the ILT/total aneurysm volume rate was lower in rAAA (55%) vs intact AAA (70%, p=0.02). Multivariate analysis determined that a shorter left CIA (OR 1.07, 95% CI 1.01 to 1.1, p=0.016) and a smaller total aneurysm volume (OR 1.007, CI. 1.001 to 1.014, p=0.016) were associated with intact AAA. After a ROC curve analysis, left CIA length <50 mm demonstrated a lower incidence of rupture (sensitivity 60% and specificity 78%), while total aneurysm volume <380 mL had 60% sensitivity and specificity. Conclusion: Large rAAAs seem to have different anatomical characteristics than similarly sized intact AAAs. Large intact AAAs have lower total aneurysm volumes and shorter left CIAs, with higher ILT/aneurysm volume rates.

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.