Endovascular repair of ruptured abdominal aortic aneurysms: A systematic review and meta-analysis

Management of Acute Diverticulitis and Incidental Abdominal Aortic Aneurysm in a 67-Year-Old Male: A Case Report of Balancing Priorities in a High-Risk Patient

Diverticular disease and abdominal aortic aneurysms (AAAs) represent distinct but significant clinical entities often associated with advanced age. Diverticulitis, a common complication of diverticular disease, can result in perforation and systemic complications, while AAAs, frequently asymptomatic, carry substantial morbidity and mortality risks if undetected or untreated. Advances in imaging have improved the early identification of these conditions, yet the simultaneous management of both presents unique challenges requiring multidisciplinary coordination. A 67-year-old male with a history of ST-elevation myocardial infarction, hypertension, hyperlipidemia, and smoking presented with left lower quadrant abdominal pain and abnormal outpatient computed tomography (CT) findings. Imaging revealed Hinchey 1a diverticulitis with a microperforation and an incidental 6.5 cm saccular AAA. The patient received conservative treatment for diverticulitis with intravenous antibiotics and transitioned to oral antibiotics upon clinical improvement. Following resolution, the patient underwent successful endovascular aneurysm repair (EVAR) for the AAA, which was complicated by a type II endoleak identified postoperatively. Blood pressure management and hydration addressed acute kidney injury, and the patient recovered well with a multidisciplinary follow-up planned. This case underscores the importance of imaging in diagnosing coexisting conditions, particularly in high-risk populations. Management required balancing the risks of treating acute diverticulitis with the need for prompt intervention for a large, saccular AAA. The conservative approach to diverticulitis, followed by elective EVAR, reflects a patient-centered strategy consistent with current guidelines. Furthermore, it underscores the critical role of adhering to screening recommendations for high-risk populations, as timely detection of asymptomatic conditions like AAAs can prevent life-threatening complications.

In-hospital mortality risk after endovascular and open aortic aneurysm repairs for ruptured abdominal aortic aneurysms

OBJECTIVE

Observational studies demonstrate reduced mortality after endovascular (EVAR) compared with open aneurysm repair (OAR) for ruptured abdominal aortic aneurysms (rAAAs). We sought to determine national trends in repair type and in-hospital mortality rates for rAAAs.

METHODS

We analyzed patients with rAAAs managed with OAR or EVAR from 2002 to 2020 in the National Inpatient Sample and evaluated annual trends in volume and in-hospital mortality by repair type. Multilevel mixed effects logistic regression model was fit for patient and system-level risk adjustment. We assessed interactions between time, sex, and Elixhauser index with repair type.

RESULTS

We examined 13,376 patients with rAAAs. Of these, 8357 (62.5%) underwent OAR. Patients receiving EVAR were slightly older (73.7 vs 72.5 years; P < .001) with slightly higher mean Elixhauser index (4.0 vs 3.8; P < .001). Unadjusted in-hospital mortality was 37.4% vs 22.4% for OAR and EVAR, respectively. EVAR offered a risk-adjusted survival advantage (odds ratio [OR], 0.39; 95% confidence interval [CI], 0.32-0.46). There was a statistically significant reduction of in-hospital mortality over time in the EVAR group (interaction OR, 0.96; 95% CI, 0.95-0.98). The interaction between Elixhauser index and repair was not statistically significant (interaction OR, 0.95; 95% CI, 0.87-1.05).

CONCLUSIONS

Survival rates for OAR and EVAR improved over time. EVAR persistently provided a substantial survival advantage over OAR in patients with rAAAs over the past 2 decades.

Endovascular Aneurysm Repair-First Strategy for Ruptured Abdominal Aortic Aneurysm Might Not Be Applicable to all Cases

BACKGROUND

We evaluate the relationship between the hospital case volume (HCV) and mortality outcomes after open aortic repair (OAR) and endovascular aortic repair (EVAR) of intact (iEVAR) and ruptured (rEVAR) abdominal aortic aneurysm (AAA) using a contemporary administrative database.

METHODS

The Healthcare Cost and Utilization Project Database for New York (2016) and New Jersey/Maryland/Florida (2016-2017) were queried using International Classification of Disease-10th edition to identify patients who had undergone OAR and EVAR. The hospitals were categorized into quartiles (Q) per overall (EVAR + OAR) volume, OAR-alone volume and EVAR-alone volume. Cox regression adjusted for confounding factors was used to estimate hazard ratios (HRs) for mortality.

RESULTS

A total of 8,825 patients (mean age, 73.5 ± 9.5 years; 6,861 male [77.7%]) had undergone 1,355 OARs and 7,470 EVARs. Overall HCV had no impact on in-hospital mortality across quartiles after (iEVAR) (range, 0.7%-1.4%, P = 0.15), (rEVAR) (range, 20.5%-29.6%, P = 0.63) and open repair of intact AAA (iOAR) (range, 4.9%-8.8%, P = 0.63). However, the mortality rates after open repair of ruptured AAA (rOAR) in highest-volume (Q4) hospitals were significantly lower than those in the 3 lower quartile hospitals (23.1% vs. 44.7%, P < 0.001). When analyzed per OAR-alone volume, the same findings were observed (22.0% for Q4 vs. 41.6% for Q1-3, P < 0.001). Furthermore, in Q4 hospitals per the OAR-alone volume analysis, the mortality hazard was greater for rEVAR (39.0%) than for rOAR (22.0%) (HR = 2.3, 95% confidence interval, 1.02-5.34, P < 0.05).

CONCLUSIONS

The mortality rates for iEVAR, rEVAR and iOAR were independent of HCV. However, after rOAR, mortality rates in high OAR volume hospitals were lower than those in the lower quartile hospitals, and, at least comparable to those of rEVAR. EVAR-first strategy for ruptured AAA might not be applicable to all cases. Patent-specific, individualized treatment should be the gold standard. For patients requiring rOAR, transfer to a regional center of excellence, when clinical safe, should be encouraged.

Machine learning algorithms for the prognostication of abdominal aortic aneurysm progression: a systematic review

INTRODUCTION

Abdominal aortic aneurysm (AAA), often characterized by an abdominal aortic diameter over 3.0 cm, is managed through screening, surveillance, and surgical intervention. AAA growth can be heterogeneous and rupture carries a high mortality rate, with size and certain risk factors influencing rupture risk. Research is ongoing to accurately predict individual AAA growth rates for personalized management. Machine learning, a subset of artificial intelligence, has shown promise in various medical fields, including endoleak detection post-EVAR. However, its application for predicting AAA growth remains insufficiently explored, thus necessitating further investigation. Subsequently, this paper aims to summarize the current status of machine learning in predicting AAA growth.

EVIDENCE ACQUISITION

A systematic database search of Embase, MEDLINE, Cochrane, PubMed and Google Scholar from inception till December 2022 was conducted of original articles that discussed the use of machine learning in predicting AAA growth using the aforementioned databases.

EVIDENCE SYNTHESIS

Overall, 2742 articles were extracted, of which seven retrospective studies involving 410 patients were included using a predetermined criteria. Six out of seven studies applied a supervised learning approach for their machine learning (ML) models, with considerable diversity observed within specific ML models. The majority of the studies concluded that machine learning models perform better in predicting AAA growth in comparison to reference models. All studies focused on predicting AAA growth over specified durations. Maximal luminal diameter was the most frequently used indicator, with alternative predictors being AAA volume, ILT (intraluminal thrombus) and flow-medicated diameter (FMD).

CONCLUSIONS

The nascent field of applying machine learning (ML) for Abdominal Aortic Aneurysm (AAA) expansion prediction exhibits potential to enhance predictive accuracy across diverse parameters. Future studies must emphasize evidencing clinical utility in a healthcare system context, thereby ensuring patient outcome improvement. This will necessitate addressing key ethical implications in establishing prospective studies related to this topic and collaboration among pivotal stakeholders within the AI field.

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.

Modified Harborview Risk Score improves ease in predicting mortality after ruptured abdominal aortic aneurysm repair

OBJECTIVE

The Harborview Risk Score (HRS) is a simple, accurate 4-point preoperative risk scoring system used to predict 30-day mortality following ruptured abdominal aortic aneurysm (rAAA) repair. The HRS assigns 1 point for each of the following: age >76 years, pH <7.2, creatinine >2 mg/dL, and any episode of severe hypotension (systolic blood pressure <70 mmHg). One potential limitation of this risk scoring system is that arterial blood gas (ABG) analysis is required to determine arterial pH. Because ABG analysis is not routinely performed prior to patient transfer or rAAA repair, we sought to determine if the HRS could be modified by replacing pH with the international normalized ratio (INR), a factor that has been previously shown to have a strong and independent association with 30-day death after rAAA repair.

METHODS

A retrospective review of all rAAA repairs done at a single academic medical center between January 2002 and December 2018 was performed. Our traditional HRS was compared with a modified score, in which pH <7.2 was replaced with INR >1.8. Patients were included if they underwent rAAA repair (open or endovascular), and if they had preoperative laboratory values available to calculate both the traditional and modified HRS.

RESULTS

During the 17-year study period, 360 of 391 repairs met inclusion criteria. Observed 30-day mortality using the modified scoring system was 17% (18/106) for a score of 0 points, 43% (53/122) for 1 point, 54% (52/96) for 2 points, 84% (27/32) for 3 points, and 100% (4/4) for 4 points. Receiver operating characteristic analysis revealed similar ability of the two scoring systems to predict 30-day death: there was no significant difference in the area under the curve (AUC) comparing the traditional (AUC = 0.74) and modified (AUC = 0.72) HRS (P = .3).

CONCLUSIONS

Although previously validated among a modern cohort of patients with rAAA, our traditional 4-point risk score is limited in real-world use by the need for an ABG. Substituting INR for pH improves the usefulness of our risk scoring system without compromising accuracy in predicting 30-day mortality after rAAA repair.

Oversizing Consideration of Proximal Stent Graft in Hemodynamically Stable and Unstable Patients Undergoing Emergent Endovascular Aortic Repair

Consideration for oversizing the proximal stent graft is suggested in endovascular aortic repair. However, a special recommendation for the proximal oversizing ratio (OSR) in patients with ruptured abdominal aortic aneurysm (rAAA) is ambiguous. This study aims to evaluate the effect of different degrees of the proximal oversizing ratio (OSR) on risk of type IA endoleak (TIAEL) in hemodynamically stable and unstable patients with rAAA undergoing emergency endovascular aortic repair (EVAR). Our study included 134 rAAA patients undergoing emergent EVAR, and we did not observe a significant association between hemodynamic instability and risk of T1AEL (HR 3.89, 95%CI 0.40-37.75, p = 0.24). All three T1AELs in the hemodynamically unstable subgroup were observed in patients with OSR ≤ 30%, but no significant difference was found regarding T1AEL between patients with OSR > 30% and OSR ≤ 30% (0.00% vs. 11.11%, p = 0.19). As for hemodynamically stable patients, OSR > 20% was associated with a significantly decreased risk of T1AEL (HR 0.03, 95%CI 0.01-0.53, p = 0.016). In conclusion, a proximal OSR > 20% is associated with a decreased risk of T1AEL in hemodynamically stable patients, while an OSR > 30% did not add an additional advantage of lowering the risk of T1AEL in hemodynamically unstable patients.

Brazilian Society for Angiology and Vascular Surgery guidelines on abdominal aortic aneurysm

The Brazilian Society of Angiology and Vascular Surgery, through the Guidelines Project, presents new Abdominal Aortic Aneurysm Guidelines, on the subject of care for abdominal aortic aneurysm patients. Its development prioritized descriptive guidelines, using the EMBASE, LILACS, and PubMed databases. References include randomized controlled trials, systematic reviews, meta-analyses, and cohort studies. Quality of evidence was evaluated by a pair of coordinators, aided by the RoB 2 Cochrane tool and the Newcastle Ottawa Scale forms. The subjects include juxtarenal aneurysms, infected aneurysms, and new therapeutic techniques, especially endovascular procedures. The current version of the guidelines include important recommendations for the primary topics involving diagnosis, treatment, and follow-up for abdominal aortic aneurysm patients, providing an objective guide for medical practice, based on scientific evidence and widely available throughout Brazil.

A protocol-based treatment for ruptured abdominal aortic aneurysm contributed to improving aorta-related mortality: a retrospective cohort study

BACKGROUND

Recent guidelines state that improving the survival rate of patients with ruptured abdominal aortic aneurysm (rAAA) requires a protocol or algorithm for the emergency management of these patients. We aimed to investigate whether introducing a protocol treatment for rAAA improves clinical outcomes compared with the pre-protocol strategy.

METHODS

At our institution, 92 patients treated for rAAA between June 2008 and August 2022 were retrospectively analyzed. In 2014, the protocol-based treatment was introduced comprising a transfer algorithm to shorten the time to proximal control, use of an endovascular occlusion balloon, strict indications for endovascular aortic aneurysm repair (EVAR) or open surgical repair, and perioperative care, including for abdominal compartment syndrome (ACS). Clinical outcomes were compared between the protocol and pre-protocol group, including operative status, all-cause mortality, and rAAA-related death at 30-day, in-hospital, and 1-year postoperative follow-ups.

RESULTS

Overall, 52 and 40 patients received the protocol-based and pre-protocol treatments, respectively. EVAR was more frequently performed in the protocol group. The rate of achieving time to proximal control was significantly faster, and the transfusion volume was lower in the protocol group. ACS occurred more frequently in the protocol group with a higher EVAR. No difference was found in all-cause mortality between the two groups. The protocol group exhibited fewer rAAA-related deaths than the pre-protocol group during the following time points: 30 days (9.6% vs. 22.5%), during the hospital stay (11.5% vs. 30.0%), and 1 year (14.5% vs. 31.5%).

CONCLUSIONS

The protocol-based treatment improved the survival rate of patients with rAAA.

Any Postoperative Surveillance Improves Survival after Endovascular Repair of Ruptured Abdominal Aortic Aneurysms

BACKGROUND

Endovascular aortic repair (EVAR) has advanced the care of patients with ruptured abdominal aortic aneurysms (rAAA) with improved early postoperative morbidity and mortality. However, this comes at the cost of a rigorous postoperative surveillance schedule to monitor for further aneurysmal degeneration. Adherence to surveillance recommendations is known to be poor in the elective setting, but has yet to be studied in the ruptured population. The aim of this study is to investigate predictors of incomplete surveillance after EVAR for rAAA (rEVAR) and examine how adherence impacts outcomes.

METHODS

This was a retrospective case control study of patients undergoing rEVAR at a multiple hospital single healthcare center (2003-2020). Patients were excluded if they underwent open conversion during their index hospitalization or died within 60 days of surgery. Follow-up was broadly categorized as complete surveillance (60-day postoperative visit and annually thereafter) or incomplete surveillance, comprising both patients with less than recommended surveillance (minimal surveillance) and completely lost to follow-up (LTF). Any follow-up was defined as patients with complete or minimal surveillance. We investigated predictors of complete versus incomplete surveillance by multivariate logistic regression. Secondary outcomes included overall survival and cumulative incidence of reintervention controlling for the competing risk of mortality, generating hazard ratios (HR) and subdistribution hazard ratios (SHR).

RESULTS

One-hundred and sixty patients (mean age 74 ± 10.1 years, 81.2% male) out of 673 total rAAA met study inclusion criteria. Complete surveillance was seen in 41.3% of our cohort, with the remainder with minimal surveillance (29.4%) or LTF (29.4%). Incomplete surveillance was associated with male sex (odds ratio [OR] 2.56; 95% CI 1.02-6.43), lack of a primary care provider (PCP; OR 0.20; 95% CI 0.04-0.99), and longer driving distance from home to treating hospital (OR 2.37; 95% CI 1.08-5.20). Survival was not different between complete and incomplete surveillance groups, however any follow-up conferred improved survival over LTF (HR 0.57; 95% CI 0.331-0.997; P = 0.049). Reintervention was associated with incomplete surveillance (SHR 0.29; 95% CI 0.11-0.75), and discharge to a facility (SHR 0.25; 95% CI 0.067-0.94).

CONCLUSIONS

Incomplete surveillance was observed in over 50% of patients who underwent rEVAR and was associated with male sex, lack of PCP, and longer driving distance. Any follow-up conferred a survival benefit, yet incomplete surveillance was associated with a lower risk of reintervention. Targeted strategies to prevent LTF, and less stringent, personalized follow-up plans that may confer similar survival benefit with better patient adherence should be investigated.

Endovascular Aortic Aneurysm Repair: A Narrative Review

Endovascular aortic aneurysm repair (EVAR) has evolved as minimally invasive method of treating infrarenal abdominal aortic aneurysms (AAA) with perioperatively mortality of less than 1% compared with 5% with open AAA repair as suggested by many randomized control trials. Computed tomography angiography is the imaging of choice for appropriate selection of a patient with EVAR. For patients with unsuitable anatomy, advanced EVARs techniques, such as fenestrated, branch, and chimney EVARs, are also increasingly being offered to patients with equal success. Patients with ruptured AAA are treated with this minimally invasive procedure. Percutaneous EVAR emerged with less of wound-related complications. Endoleaks are the most common complications peculiar to this procedure, and most are preventable by preoperative planning. They are detected on completion angiogram or on the surveillance imaging. This review discusses indications of EVAR, its selection criteria, procedural steps, and common complications associated with this procedure and advanced EVARs.

Preoperative risk score accuracy confirmed in a modern ruptured abdominal aortic aneurysm experience

OBJECTIVE

Various risk score calculators used to predict 30-day mortality after treatment of ruptured abdominal aortic aneurysms (rAAAs) have produced mixed results regarding their usefulness and reproducibility. We prospectively validated the accuracy of our preoperative scoring system in a modern cohort of patients with rAAAs.

METHODS

A retrospective review of all patients wiith rAAAs who had presented to a single academic center from January 2002 to December 2018 was performed. The patients were divided into three cohorts according to when the institutional practice changes had occurred: the pre-endovascular aneurysm repair (EVAR) era (January 2002 to July 2007), the pre-Harbor View risk score era (August 2007 to October 2013), and the modern era (November 2013 to December 2018). The primary outcome measure was 30-day mortality. Our preoperative risk score assigns 1 point for each of the following: age >76 years, pH <7.2, creatinine >2 mg/dL, and any episode of hypotension (systolic blood pressure <70 mm Hg). The previously reported mortality from a retrospective analysis of the first two cohorts was 22% for 1 point, 69% for 2 points, 78% for 3 points, and 100% for 4 points. The goal of the present study was to prospectively validate the Harborview scoring system in the modern era.

RESULTS

During the 17-year study period, 417 patients with rAAAs were treated at our institution. Of the 118 patients treated in the modern era, 45 (38.1%) had undergone open aneurysm repair (OAR), 61 (51.7%) had undergone EVAR, and 12 (10.2%) had received comfort measures only. Excluding the 12 patients without aneurysm repair, we found a statistically significant linear trend between the preoperative risk score and subsequent 30-day mortality for all patients combined (P < .0001), for OAR patients alone (P = .0003), and for EVAR patients alone (P < .0001). After adjustment for the Harborview risk score, the 30-day mortality was 41.3% vs 31.6% after OAR vs EVAR, respectively (P = .2). For all repairs, the 30-day mortality was 14.6% for a score of 0, 35.7% for a score of 1, 68.4% for a score of 2, and 100% for a score of 3 or 4.

CONCLUSIONS

Our results, representing one of the largest modern series of rAAAs treated at a single institution, have confirmed the accuracy of a simple 4-point preoperative risk score in predicting 30-day mortality in the modern rAAA patient. Such tools should be used when discussing the treatment options with referring physicians, patients, and their family members to help guide transfer and treatment decision-making.

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.

Hybrid emergency room management of a ruptured abdominal aortic aneurysm

Patients with a ruptured abdominal aortic aneurysm (rAAA) still have high mortality. Rapid diagnosis and treatment are vital for improving survival outcomes. rAAA management has evolved regarding these factors. We have reported the case of a 70-year-old man with an rAAA that was rapidly diagnosed and treated in a hybrid emergency room (ER). A hybrid ER is an integrated ER capable of computed tomography scanning, interventional radiology, and surgery in one place. In the present case, the door-to-intervention time was 35 minutes. The use of hybrid ERs has the potential to enhance the speed and quality of diagnostic and definitive treatment of rAAAs.

Endograft type and anesthesia mode are associated with mortality of endovascular aneurysm repair for ruptured abdominal aortic aneurysms

OBJECTIVE

Endovascular aneurysm repair has become the primary treatment modality for ruptured infrarenal abdominal aortic aneurysm. This study examines the impact of endograft type on perioperative outcomes for ruptured infrarenal abdominal aortic aneurysm.

METHOD

The targeted endovascular aneurysm repair files of the American College of Surgeons National Surgical Quality Improvement Program database (2012-2017) were used. Only patients treated for ruptured infrarenal abdominal aortic aneurysm were included. All patients requiring concomitant stenting of the visceral arteries or aneurysmal iliac arteries or open abdominal surgery were excluded. The characteristics of patients treated with the different endografts and the corresponding outcomes were compared using Stata software.

RESULTS

There were 479 patients treated with the three most common endografts: Cook Zenith (n = 127), Gore Excluder (n = 239), and Medtronic Endurant (n = 113). The number of other endografts was too small for statistical analysis. Compared to patients treated with Excluder or Endurant, the patients treated with Zenith had significantly lower body mass index (P < .001) and were less likely to be white (P < .001). On the other hand, patients treated with Endurant were less likely to be smoker (P = .016). Patients treated with Zenith had significantly larger ruptured infrarenal abdominal aortic aneurysm diameter (P = .045). The overall mortality was 18% and morbidity 74.3%. There was a statistically significant difference in overall mortality (Zenith = 11.8%, Excluder = 18%, Endurant = 24.8%, P = .033) but not morbidity (P = .808) between the three groups. Post hoc analysis for overall mortality showed only significant difference between Zenith and Endurant. The difference in mortality was not significant in patients presenting with ruptured infrarenal abdominal aortic aneurysm without hypotension (P = .065). On multivariable analysis, treatment with the Endurant endograft was associated with increased mortality compared to Zenith (odds ratio = 3.0 [confidence interval 1.31-6.7]). General anesthesia (odds ratio = 2.67 [confidence interval 1.02-7.02]), rupture with hypotension (odds ratio = 4.49 [confidence interval 2.54-7.95]), and dependent functional status (odds ratio = 5.7 [confidence interval 1.96-16.59]) were independently associated with increased mortality while increasing body mass index (odds ratio = 0.97 [confidence interval 0.95-0.99]) was associated with reduced risk of mortality.

CONCLUSIONS

This study highlights contemporary outcomes of endovascular aneurysm repair for ruptured infrarenal abdominal aortic aneurysm with relatively low mortality. Endograft type and anesthesia technique are modifiable factors that can potentially improve outcomes. Significant variation in the outcomes of the different endografts warrants further research.

Feasibility and Safety of Sac Embolization Using N-Butyl Cyanoacrylate in Emergency Endovascular Aneurysm Repair for Ruptured Abdominal Aortic Aneurysms or Isolated Iliac Artery Aneurysms

PURPOSE

To evaluate the feasibility and safety of sac embolization with N-butyl cyanoacrylate (NBCA) in emergency endovascular aneurysm repair (EVAR) for ruptured abdominal aortic aneurysm (AAA) and iliac artery aneurysm (IAA) in comparison to EVAR without sac embolization.

MATERIALS AND METHODS

Between February 2012 and December 2019, among 44 consecutive patients with ruptured AAA or IAA, 29 underwent EVAR. Of these, 22 patients (median age 77.5 years; 18 men) had concomitant sac embolization using NBCA; the remaining 7 patients (median age 88 years; 6 men) underwent EVAR without sac embolization and form the control group. The technical success, clinical success (hemodynamic stabilization), procedure-related complications, and mortality were compared between the groups.

RESULTS

All EVAR procedures and embolizations were successful. The clinical success rates in the NBCA and control groups were 95% (21/22) and 71% (5/7), respectively (p=0.14). There was no complication related to the procedure. Type II endoleak occurred in 4 of 21 patients (19%) in the NBCA group vs none of the control patients. One patient (5%) died in the NBCA group vs 3 (43%) in the controls (p=0.034).

CONCLUSION

Sac embolization using NBCA in emergency EVAR appears to be feasible and safe for ruptured AAA and IAA.

A Comparative Classification Analysis of Abdominal Aortic Aneurysms by Machine Learning Algorithms

The objective of this work was to perform image-based classification of abdominal aortic aneurysms (AAA) based on their demographic, geometric, and biomechanical attributes. We retrospectively reviewed existing demographics and abdominal computed tomography angiography images of 100 asymptomatic and 50 symptomatic AAA patients who received an elective or emergent repair, respectively, within 1-6 months of their last follow up. An in-house script developed within the MATLAB computational platform was used to segment the clinical images, calculate 53 descriptors of AAA geometry, and generate volume meshes suitable for finite element analysis (FEA). Using a third party FEA solver, four biomechanical markers were calculated from the wall stress distributions. Eight machine learning algorithms (MLA) were used to develop classification models based on the discriminatory potential of the demographic, geometric, and biomechanical variables. The overall classification performance of the algorithms was assessed by the accuracy, area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and precision of their predictions. The generalized additive model (GAM) was found to have the highest accuracy (87%), AUC (89%), and sensitivity (78%), and the third highest specificity (92%), in classifying the individual AAA as either asymptomatic or symptomatic. The k-nearest neighbor classifier yielded the highest specificity (96%). GAM used seven markers (six geometric and one biomechanical) to develop the classifier. The maximum transverse dimension, the average wall thickness at the maximum diameter, and the spatially averaged wall stress were found to be the most influential markers in the classification analysis. A second classification analysis revealed that using maximum diameter alone results in a lower accuracy (79%) than using GAM with seven geometric and biomechanical markers. We infer from these results that biomechanical and geometric measures by themselves are not sufficient to discriminate adequately between population samples of asymptomatic and symptomatic AAA, whereas MLA offer a statistical approach to stratification of rupture risk by combining demographic, geometric, and biomechanical attributes of patient-specific AAA.

The Use of Closure Devices for Aortic Stent-Graft Insertion: Outcomes Following a Paradigm Shift to Percutaneous Access in a Tertiary Vascular Center

Background:

This retrospective case series aims to evaluate the efficacy of the Perclose ProGlide system for postoperative hemostasis following aortic stent-graft insertion.

Material and Methods:

A prospectively maintained database of patients with a minimum follow-up of 12 months following percutaneous aortic procedures was interrogated. Preprocedural computed tomography (CT) scans were reviewed to assess existing stenosis in the common femoral artery (CFA). Arteries with an estimated stenosis of greater than 25% on visual inspection underwent quantification using multiplanar and curved planar reformation. The preoperative and 1-year follow-up CTs of these patients were assessed for change in stenosis. Analysis was performed by 2 independent reviewers, with senior authors reviewing any discrepancies.

Results:

One hundred forty-two endovascular aortic aneurysm repairs (EVARs) were performed. The ProGlide system was used in 235 arteries, yielding a high success rate in obtaining postprocedural hemostasis (94%). There were 13 postprocedural access-related complications, including 5 patients requiring surgical closure due to inadequate seal. Two patients required thrombectomy due to distal embolization. One patient required CFA endarterectomy at 6 months for the treatment of preexisting short distance claudication. Vessel analysis was performed in 31 arteries. Mean preoperative stenosis was 32% (range: 20%-57%). Mean postoperative stenosis was 32% (21%-57%). No significant change in degree of stenosis was detected (defined as a 5% change).

Conclusions:

The ProGlide system yielded a high success rate in obtaining postoperative hemostasis with low rate of conversion to surgical closure and low complication rates. There was no evidence of worsening vessel stenosis in arteries with preprocedural stenotic disease.

Level of Evidence:

Level 4, Case Series.

Strategy of endovascular versus open repair for patients with clinical diagnosis of ruptured abdominal aortic aneurysm: the IMPROVE RCT

BACKGROUND

Ruptured abdominal aortic aneurysm (AAA) is a common vascular emergency. The mortality from emergency endovascular repair may be much lower than the 40-50% reported for open surgery.

OBJECTIVE

To assess whether or not a strategy of endovascular repair compared with open repair reduces 30-day and mid-term mortality (including costs and cost-effectiveness) among patients with a suspected ruptured AAA.

DESIGN

Randomised controlled trial, with computer-generated telephone randomisation of participants in a 1 : 1 ratio, using variable block size, stratified by centre and without blinding.

SETTING

Vascular centres in the UK (n = 29) and Canada (n = 1) between 2009 and 2013.

PARTICIPANTS

A total of 613 eligible participants (480 men) with a ruptured aneurysm, clinically diagnosed at the trial centre.

INTERVENTIONS

A total of 316 participants were randomised to the endovascular strategy group (immediate computerised tomography followed by endovascular repair if anatomically suitable or, if not suitable, open repair) and 297 were randomised to the open repair group (computerised tomography optional).

MAIN OUTCOME MEASURES

The primary outcome measure was 30-day mortality, with 30-day reinterventions, costs and disposal as early secondary outcome measures. Later outcome measures included 1- and 3-year mortality, reinterventions, quality of life (QoL) and cost-effectiveness.

RESULTS

The 30-day mortality was 35.4% in the endovascular strategy group and 37.4% in the open repair group [odds ratio (OR) 0.92, 95% confidence interval (CI) 0.66 to 1.28; p = 0.62, and, after adjustment for age, sex and Hardman index, OR 0.94, 95% CI 0.67 to 1.33]. The endovascular strategy appeared to be more effective in women than in men (interaction test p = 0.02). More discharges in the endovascular strategy group (94%) than in the open repair group (77%) were directly to home (p < 0.001). Average 30-day costs were similar between groups, with the mean difference in costs being -£1186 (95% CI -£2997 to £625), favouring the endovascular strategy group. After 1 year, survival and reintervention rates were similar in the two groups, QoL (at both 3 and 12 months) was higher in the endovascular strategy group and the mean cost difference was -£2329 (95% CI -£5489 to £922). At 3 years, mortality was 48% and 56% in the endovascular strategy group and open repair group, respectively (OR 0.73, 95% CI 0.53 to 1.00; p = 0.053), with a stronger benefit for the endovascular strategy in the subgroup of 502 participants in whom repair was started for a proven rupture (OR 0.62, 95% CI 0.43 to 0.89; p = 0.009), whereas aneurysm-related reintervention rates were non-significantly higher in this group. At 3 years, considering all participants, there was a mean difference of 0.174 quality-adjusted life-years (QALYs) (95% CI 0.002 to 0.353 QALYs) and, among the endovascular strategy group, a cost difference of -£2605 (95% CI -£5966 to £702), leading to 88% of estimates in the cost-effectiveness plane being in the quadrant showing the endovascular strategy to be 'dominant'.

LIMITATIONS

Because of the pragmatic design of this trial, 33 participants in the endovascular strategy group and 26 in the open repair group breached randomisation allocation.

CONCLUSIONS

The endovascular strategy was not associated with a significant reduction in either 30-day mortality or cost but was associated with faster participant recovery. By 3 years, the endovascular strategy showed a survival and QALY gain and was highly likely to be cost-effective. Future research could include improving resuscitation for older persons with circulatory collapse, the impact of local anaesthesia and emergency consent procedures.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN48334791 and NCT00746122.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 31. See the NIHR Journals Library website for further project information.

Recent Advances and Mid-to-Long Term Results of Endovascular Aneurysm Repair for Abdominal Aortic Aneurysms

Endovascular aneurysm repair (EVAR) has become the standard therapy alongside open surgery repair (OSR) for abdominal aortic aneurysm (AAA) and it is rapidly becoming prevalent. There has been substantial technical progress with respect to EVAR since its introduction. Technical contrivance can be used to manage even inappropriate EVAR cases, including those involving a hostile neck, deficient access route, or aneurysm rupture. However, there are some controversies over reinterventions in relation to long-term outcomes. Although a long-term result has not yet been analyzed in Japan a randomized controlled trial (RCT) held in the West reported that OSR is superior to EVAR for avoiding reinterventions and aneurysm-related death. The RCT involved the use of older devices and proceeded in a different way from the present study; therefore, different results may be obtained for Japanese EVAR outcomes. However, this Western RCT result should be considered as an important warning. Type II endoleak also must be managed in order to improve long term outcomes of EVAR. Efforts to improve both technical methodology and long-term outcomes are necessary to ensure EVAR as a minimally invasive therapy for patients with AAA. (This is a translation of Jpn J Vasc Surg 2018; 27: 405-411.).

Epidemiology and contemporary management of abdominal aortic aneurysms

Abdominal aortic aneurysm (AAA) is most commonly defined as a maximal diameter of the abdominal aorta in excess of 3 cm in either anterior-posterior or transverse planes or, alternatively, as a focal dilation ≥ 1.5 times the diameter of the normal adjacent arterial segment. Risk factors for the development of AAA include age > 60, tobacco use, male gender, Caucasian race, and family history of AAA. Aneurysm growth and rupture risk appear to be associated with persistent tobacco use, female gender, and chronic pulmonary disease. The majority of AAAs are asymptomatic and detected incidentally on various imaging studies, including abdominal ultrasound, and computed tomographic angiography. Symptoms associated with AAA may include abdominal or back pain, thromboembolization, atheroembolization, aortic rupture, or development of an arteriovenous or aortoenteric fistula. The Screening Abdominal Aortic Aneurysms Efficiently (SAAAVE) Act provides coverage for a one-time screening abdominal ultrasound at age 65 for men who have smoked at least 100 cigarettes and women who have family history of AAA disease. Medical management is recommended for asymptomatic patients with AAAs < 5 cm in diameter and focuses on modifiable risk factors, including smoking cessation and blood pressure control. Primary indications for intervention in patients with AAA include development of symptoms, rupture, rapid aneurysm growth (> 5 mm/6 months), or presence of a fusiform aneurysm with maximum diameter of 5.5 cm or greater. Intervention for AAA includes conventional open surgical repair and endovascular aortic stent graft repair.

Comparative clinical effectiveness and cost effectiveness of endovascular strategy v open repair for ruptured abdominal aortic aneurysm: three year results of the IMPROVE randomised trial

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

Open versus endovascular repair of ruptured abdominal aortic aneurysms: What have we learned after more than 2 decades of ruptured endovascular aneurysm repair?

BACKGROUND

Ruptured abdominal aortic aneurysm is one of the most difficult clinical problems in surgical practice, with extraordinarily high morbidity and mortality. During the past 23 years, the literature has become replete with reports regarding ruptured endovascular aneurysm repair.

METHODS

A variety of study designs and databases have been utilized to compare ruptured endovascular aneurysm repair and open surgical repair for ruptured abdominal aortic aneurysm and studies of various designs from different databases have yielded vastly different conclusions. It therefore remains controversial whether ruptured endovascular aneurysm repair improves outcomes after ruptured abdominal aortic aneurysm in comparison to open surgical repair.

RESULTS

The purpose of this article is to review the best available evidence comparing ruptured endovascular aneurysm repair and open surgical repair of ruptured abdominal aortic aneurysm, including single institution and multi-institutional retrospective observational studies, large national population-based studies, large national registries of prospectively collected data, and randomized controlled clinical trials.

CONCLUSION

This article will analyze the study designs and databases utilized with their attendant strengths and weaknesses to understand the sometimes vastly different conclusions the studies have reached. This article will attempt to integrate the data to distill some of the lessons that have been learned regarding ruptured endovascular aneurysm repair and identify ongoing needs in this field.

The effect of endograft device on patient outcomes in endovascular repair of ruptured abdominal aortic aneurysms

Objective

Endovascular aneurysm repair for ruptured abdominal aortic aneurysm is being increasingly applied as the intervention of choice. The purpose of this study was to determine whether survival and reintervention rates after ruptured abdominal aortic aneurysm vary between endograft devices.

Methods

This cohort study identified all ruptured abdominal aortic aneurysms performed at The Ottawa Hospital from January 1999 to May 2015. Data collected included patient demographics, stability index at presentation, adherence to device instructions for use, endoleaks, reinterventions, and mortality. Kruskal–Wallis test was used to compare outcomes between groups. Mortality outcomes were assessed using Kaplan–Meier survival analysis, and multivariate Cox regression modeling.

Results

One thousand sixty endovascular aneurysm repairs were performed using nine unique devices. Ninety-six ruptured abdominal aortic aneurysms were performed using three devices: Cook Zenith ( n = 46), Medtronic Endurant ( n = 33), and Medtronic Talent ( n = 17). The percent of patients presented in unstable or extremis condition was 30.2, which did not differ between devices. Overall 30-day mortality was 18.8%, and was not statistically different between devices ( p = 0.16), although Medtronic Talent had markedly higher mortality (35.3%) than Cook Zenith (15.2%) and Medtronic Endurant (15.2%). AUI configuration was associated with increased 30-day mortality (33.3% vs. 12.1%, p = 0.02). Long-term mortality and graft-related reintervention rates at 30 days and 5 years were similar between devices. Instructions for use adherence was similar across devices, but differed between the ruptured abdominal aortic aneurysm and elective endovascular aneurysm repair cohorts (47.7% vs. 79.0%, p < 0.01). Notably, two patients who received Medtronic Talent grafts underwent open conversion >30 days post-endovascular aneurysm repair ( p = 0.01). Type 1 endoleak rates differed significantly across devices (Cook Zenith 0.0%, Medtronic Endurant 18.2%, Medtronic Talent 17.6%, p = 0.01).

Conclusion

Although we identified device-related differences in endoleak rates, there were no significant differences in reintervention rates or mortality outcomes. Favorable outcomes of Cook Zenith and Medtronic Endurant over Medtronic Talent reflect advances in endograft technology and improvements in operator experience over time. Results support selection of endograft by operator preference for ruptured abdominal aortic aneurysm.

Treatment of Abdominal Aortic Pathology

Abdominal aortic pathology is a diverse topic, ranging through a broad span of possible pathologies. The treatment options are equally vast, particularly with the ever-expanding endovascular techniques. In this article, we discuss management strategies for abdominal aortic aneurysms and aortic occlusive disease, because they represent some of the most common pathologies encountered in clinical scenarios.

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

OBJECTIVE/BACKGROUND

The Dutch Surgical Aneurysm Audit (DSAA) is mandatory for all patients with primary abdominal aortic aneurysms (AAAs) in the Netherlands. The aims are to present the observed outcomes of AAA surgery against the predicted outcomes by means of V-POSSUM (Vascular-Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity). Adjusted mortality was calculated by the original and re-estimated V(physiology)-POSSUM for hospital comparisons.

METHODS

All patients operated on from January 2013 to December 2014 were included for analysis. Calibration and discrimination of V-POSSUM and V(p)-POSSUM was analysed. Mortality was benchmarked by means of the original V(p)-POSSUM formula and risk-adjusted by the re-estimated V(p)-POSSUM on the DSAA.

RESULTS

In total, 5898 patients were included for analysis: 4579 with elective AAA (EAAA) and 1319 with acute abdominal aortic aneurysm (AAAA), acute symptomatic (SAAA; n = 371) or ruptured (RAAA; n = 948). The percentage of endovascular aneurysm repair (EVAR) varied between hospitals but showed no relation to hospital volume (EAAA: p = .12; AAAA: p = .07). EAAA, SAAA, and RAAA mortality was, respectively, 1.9%, 7.5%, and 28.7%. Elective mortality was 0.9% after EVAR and 5.0% after open surgical repair versus 15.6% and 27.4%, respectively, after AAAA. V-POSSUM overestimated mortality in most EAAA risk groups (p < .01). The discriminative ability of V-POSSUM in EAAA was moderate (C-statistic: .719) and poor for V(p)-POSSUM (C-statistic: .665). V-POSSUM in AAAA repair overestimated in high risk groups, and underestimated in low risk groups (p < .01). The discriminative ability in AAAA of V-POSSUM was moderate (.713) and of V(p)-POSSUM poor (.688). Risk adjustment by the re-estimated V(p)-POSSUM did not have any effect on hospital variation in EAAA but did in AAAA.

CONCLUSION

Mortality in the DSAA was in line with the literature but is not discriminative for hospital comparisons in EAAA. Adjusting for V(p)-POSSUM, revealed no association between hospital volume and treatment or outcome. Risk adjustment for case mix by V(p)-POSSUM in patients with AAAA has been shown to be important.

Endovascular vs. Open Repair for Ruptured Abdominal Aortic Aneurysm

BACKGROUND

Patients presenting with ruptured abdominal aortic aneurysms are most often treated with open repair despite the fact that endovascular aneurysm repair is a less invasive and widely accepted method with clear benefits for elective aortic aneurysm patients. A debate exists regarding the definitive benefit in endovascular repair for patients with a ruptured abdominal aortic aneurysm. The aim of this literature review was to determine if any trends exist in favor of either open or endovascular repair.

MATERIAL AND METHODS

A literature search was performed using PUBMED, OVID, and Google Scholar databases. The search yielded 64 publications.

RESULTS

Out of 64 publications, 25 were retrospective studies, 12 were population-based, 21 were prospective, 5 were the results of RCTs, and 1 was a case-series. Sixty-one studies reported on early mortality and provided data comparing endovascular repair (rEVAR) and open repair (rOR) for ruptured abdominal aneurysm groups. Twenty-nine of these studies reported that rEVAR has a lower early mortality rate. Late mortality after rEVAR compared to that of rOR was reported in 21 studies for a period of 3 to 60 months. Results of 61.9% of the studies found no difference in late mortality rates between these 2 groups. Thirty-nine publications reported on the incidence of complications. Approximately half of these publications support that the rEVAR group has a lower complication rate and the other half found no difference between the groups. Length of hospital stay has been reported to be shorter for rEVAR in most studies. Blood loss and need for transfusion of either red cells or fresh frozen plasma was consistently lower in the rEVAR group.

CONCLUSIONS

Differences between the included publications affect the outcomes. Randomized control trials have not been able to provide clear conclusions. rEVAR can now be considered a safe method of treating rAAA, and is at least equal to the well-established rOR method.

Analysis of in hospital mortality and long-term survival excluding in hospital mortality after open surgical repair of ruptured abdominal aortic aneurysm

Purpose

The aim of this study was to confirm the factors that affect the mortality associated with the open surgical repair of ruptured abdominal aortic aneurysm (rAAA) and to analyze the long-term survival rates.

Methods

A retrospective review was performed on a prospectively collected database that included 455 consecutive patients who underwent open surgical repair for AAA between January 2001 and December 2012. We divided our analysis into in-hospital and postdischarge periods and analyzed the risk factors that affected the long-term survival of rAAA patients.

Results

Of the 455 patients who were initially screened, 103 were rAAA patients, and 352 were non-rAAA (nAAA) patients. In the rAAA group, 25 patients (24.2%) died in the hospital and 78 were discharged. Long-term survival was significantly better in the nAAA group (P = 0.001). The 2-, 5-, and 10-year survival rates of the rAAA patients were 87%, 73.4%, and 54.1%, respectively. Age (hazard ratio [HR], 1.05; 95% confidence interval [CI], 1.02–.08; P < 0.001) and aneurysm rupture (HR, 1.96; 95% CI, 1.12–.44; P = 0.01) significantly affected long-term survival.

Conclusion

Preoperative circulatory failure is the most common cause of death for in-hospital mortality of rAAA patients. After excluding patients who have died during the perioperative period, age is the only factor that affects the survival of rAAA patients.

Open Repair of Ruptured Abdominal Aortic Aneurysm: The Suitability of Endovascular Aneurysm Repair Does Not Influence Operative Mortality

Purpose:

We analyze the outcomes of open repair (OR) in patients with ruptured abdominal aortic aneurysm (RAAA) according to the anatomic suitability for endovascular aneurysm repair (EVAR).

Materials and Methods:

We reviewed retrospectively all consecutive RAAA patients who underwent OR from January 2005 to March 2014. All suspected patients underwent preoperative computed tomography (CT). Outcomes were major morbidities and mortality. Multivariate analysis was performed by using logistic regression adjusted by controlled variables; gender, Hardman index, maximal aneurysmal diameter, rupture type, perioperative transfusion requirement, and perioperative urinary output.

Results:

Among 54 consecutive patients with RAAA who underwent OR, 45 patients were included after exclusion of 9 patients (7, suprarenal; 1, infected; 1, inflammatory). Preoperative CT showed 27% (12/45) EVAR-suitable patients. Hostile neck anatomy was found in 88% (29/33) among unsuitable anatomy (UA) (n=33). The maximal aneurysmal diameter was statistically larger (83.1±21.0 mm vs. 68.8±12.3 mm, P=0.032) in the UA group. The 30-day mortality was 28.9% (13/45; 33% vs. 17% in UA group vs. suitable anatomy [SA] group, P=0.460; adjusted P=0.445). UA group had more patients with cardiac morbidity (55% vs. 25%, P=0.079; adjusted P=0.032; odds ratio, 12.914; 95% confidence interval, 1.238–134.675). There was no statistical difference in survival rate between SA and UA groups (74.1%, 74.1%, and 74.1% vs. 60.6%, 55.6%, and 32.4% at 1-, 3- and 5-year, respectively; P=0.145).

Conclusion:

In this study, relatively unfavorable outcomes were found in the EVAR-unsuitable group after OR in RAAA patients. However, unsuitable anatomy did not influence patient survival after OR by multivariate analysis.

WSES position paper on vascular emergency surgery

Trauma, both blunt and penetrating, is extremely common worldwide, as trauma to major vessels. The management of these patients requires specialized surgical skills and techniques of the trauma surgeon. Furthermore few other surgical emergencies require immediate diagnosis and treatment like a ruptured abdominal aortic aneurysm (rAAA). Mortality of patients with a rAAA reaches 85 %, with more than half dying before reaching the hospital. These are acute events demanding immediate intervention to save life and limb and precluding any attempt at transfer or referral. It is the purpose of this position paper to discuss neck, chest, extremities and abdominal trauma, bringing to light recent evidence based data as well as expert opinions; besides, in this paper we present a review of the recent literature on rAAA and we discuss the rationale for transfer to referral center, the role of preoperative imaging and the pros and cons of Endoluminal repair of rAAA (REVAR) versus Open Repair (OR).

Life-Saving Embolization in a Patient with Recurrent Shock Due to a Type II Endoleak after Endovascular Aortic Repair for a Ruptured Abdominal Aortic Aneurysm

A man in his 80s underwent urgent endovascular aortic repair (EVAR) for a ruptured abdominal aortic aneurysm (RAAA). Surgery was completed without apparent complications, and the patient was returned to the Cardiac Care Unit. Two hours later, he again developed shock, and contrast-enhanced Computed Tomography showed extravasation from a type II endoleak (T2EL) involving the IMA. Transcatheter arterial embolization (TAE) was immediately performed, and the patient's vital signs stabilized soon after embolization. Abdominal compartment syndrome was suspected during the procedure, so a retroperitoneal hematoma evacuation was performed. The patient's postoperative course was satisfactory, and he transferred to another hospital. EVAR for RAAA would be useful, but it is necessary to be considered that T2EL can cause the aggravation of unstable circulation.

Individual-patient meta-analysis of three randomized trials comparing endovascular versus open repair for ruptured abdominal aortic aneurysm

BACKGROUND

The benefits of endovascular repair of ruptured abdominal aortic aneurysm remain controversial, without any strong evidence about advantages in specific subgroups.

METHODS

An individual-patient data meta-analysis of three recent randomized trials of endovascular versus open repair of abdominal aortic aneurysm was conducted according to a prespecified analysis plan, reporting on results to 90 days after the index event.

RESULTS

The trials included a total of 836 patients. The mortality rate across the three trials was 31.3 per cent for patients randomized to endovascular repair/strategy and 34.0 per cent for those randomized to open repair at 30 days (pooled odds ratio 0.88, 95 per cent c.i. 0.66 to 1.18), and 34.3 and 38.0 per cent respectively at 90 days (pooled odds ratio 0.85, 0.64 to 1.13). There was no evidence of significant heterogeneity in the odds ratios between trials. Mean(s.d.) aneurysm diameter was 8.2(1.9) cm and the overall in-hospital mortality rate was 34.8 per cent. There was no significant effect modification with age or Hardman index, but there was indication of an early benefit from an endovascular strategy for women. Discharge from the primary hospital was faster after endovascular repair (hazard ratio 1.24, 95 per cent c.i. 1.04 to 1.47). For open repair, 30-day mortality diminished with increasing aneurysm neck length (adjusted odds ratio 0.69 (95 per cent c.i. 0.53 to 0.89) per 15 mm), but aortic diameter was not associated with mortality for either type of repair.

CONCLUSION

Survival to 90 days following an endovascular or open repair strategy is similar for all patients and for the restricted population anatomically suitable for endovascular repair. Women may benefit more from an endovascular strategy than men and patients are, on average, discharged sooner after endovascular repair.

The effect of aortic morphology on peri-operative mortality of ruptured abdominal aortic aneurysm

AIMS

To investigate whether aneurysm shape and extent, which indicate whether a patient with ruptured abdominal aortic aneurysm (rAAA) is eligible for endovascular repair (EVAR), influence the outcome of both EVAR and open surgical repair.

METHODS AND RESULTS

The influence of six morphological parameters (maximum aortic diameter, aneurysm neck diameter, length and conicality, proximal neck angle, and maximum common iliac diameter) on mortality and reinterventions within 30 days was investigated in rAAA patients randomized before morphological assessment in the Immediate Management of the Patient with Rupture: Open Versus Endovascular strategies (IMPROVE) trial. Patients with a proven diagnosis of rAAA, who underwent repair and had their admission computerized tomography scan submitted to the core laboratory, were included. Among 458 patients (364 men, mean age 76 years), who had either EVAR (n = 177) or open repair (n = 281) started, there were 155 deaths and 88 re-interventions within 30 days of randomization analysed according to a pre-specified plan. The mean maximum aortic diameter was 8.6 cm. There were no substantial correlations between the six morphological variables. Aneurysm neck length was shorter in those undergoing open repair (vs. EVAR). Aneurysm neck length (mean 23.3, SD 16.1 mm) was inversely associated with mortality for open repair and overall: adjusted OR 0.72 (95% CI 0.57, 0.92) for each 16 mm (SD) increase in length. There were no convincing associations of morphological parameters with reinterventions.

CONCLUSION

Short aneurysm necks adversely influence mortality after open repair of rAAA and preclude conventional EVAR. This may help explain why observational studies, but not randomized trials, have shown an early survival benefit for EVAR.

CLINICAL TRIAL REGISTRATION

ISRCTN 48334791.

Rupture signs on computed tomography, treatment, and outcome of abdominal aortic aneurysms

OBJECTIVES

Abdominal aortic aneurysm (AAA) rupture has a high mortality rate. Although the diagnosis of a ruptured AAA is usually straightforward, detection of impending rupture signs can be more challenging. Early diagnosis of impending AAA rupture can be lifesaving. Furthermore, differentiating between impending and complete rupture has important repercussions on patient management and prognosis. The purpose of this article is to classify and illustrate the entire spectrum of AAA rupture signs and to review current treatment options for ruptured AAAs.

METHODS

Using medical illustrations supplemented with computed tomography (CT), this essay showcases the various signs of impending rupture and ruptured AAAs. Endovascular aneurysm repair (EVAR) and open surgical repair are also discussed as treatment options for ruptured AAAs.

RESULTS

CT imaging findings of ruptured AAAs can be categorised according to location: intramural, luminal, and extraluminal. Intramural signs generally indicate impending AAA rupture, whereas luminal and extraluminal signs imply complete rupture. EVAR has emerged as an alternative and possibly less morbid method to treat ruptured AAAs.

CONCLUSIONS

AAA rupture occurs at the end of a continuum of growth and wall weakening. This review describes the CT imaging findings that may help identify impending rupture prior to complete rupture.

TEACHING POINTS

• AAA rupture occurs at the end of a continuum of growth and wall weakening. • Intramural imaging findings indicate impending AAA rupture. • Luminal and extraluminal imaging findings imply complete AAA rupture. • Some imaging findings are not specific to AAA ruptures and can be seen in other pathologies. • EVAR has emerged as an alternative and possibly less morbid method of treating ruptured AAAs.

In meta-analyses of proportion studies, funnel plots were found to be an inaccurate method of assessing publication bias

OBJECTIVE

To assess the utility of funnel plots in assessing publication bias (PB) in meta-analyses of proportion studies.

STUDY DESIGN AND SETTING

Meta-analysis simulation study and meta-analysis of published literature reporting peri-operative mortality after abdominal aortic aneurysm (AAA) repair. Data for the simulation study were stochastically generated. A literature search of Medline and Embase was performed to identify studies for inclusion in the published literature meta-analyses.

RESULTS

The simulation study demonstrated that conventionally constructed funnel plots (log odds vs. 1/standard error [1/SE]) for extreme proportional outcomes were asymmetric despite no PB. Alternative funnel plots constructed using study size rather than 1/SE showed no asymmetry for extreme proportional outcomes. When used in meta-analyses of the mortality of AAA repair, these alternative funnel plots highlighted the possibility for conventional funnel plots to demonstrate asymmetry when there was no evidence of PB.

CONCLUSION

Conventional funnel plots used to assess for potential PB in meta-analyses are inaccurate for meta-analyses of proportion studies with low proportion outcomes. Funnel plots of study size against log odds may be a more accurate way of assessing for PB in these studies.

Improved results in the management of ruptured abdominal aortic aneurysm may not be on the basis of endovascular aneurysm repair alone

Recent improvement in the survival of patients presenting with a ruptured abdominal aortic aneurysm (rAAA) has been credited to endovascular aneurysm repair (EVAR). We present our clinical series in the management of rAAA from 2007 to 2011. A total of 55 consecutive patient charts were reviewed. Thirty-eight patients underwent EVAR, 17 of the 55 patients did not have favorable anatomy for EVAR. Nine of the 17 patients underwent standard open repair. Eight patients underwent a 'hybrid repair' defined as suprarenal aortic endovascular balloon control followed by open repair. Overall 30-day mortality for all 55 patients was 22%. Mortality for the patients managed by endovascular aortic aneurysm repair was 26% compared with 22% with open repair. There were no deaths in the eight patients undergoing the hybrid repair. Endovascular balloon control of the aorta followed by open rAAA repair in patients who are not candidates for rEVAR has produced good results in our experience. Improved results being reported in the management of rAAA may not be on the basis of endovascular repair alone.