Editor's Choice - Detection of Late Complications After Endovascular Abdominal Aortic Aneurysm Repair and Implications for Follow up Based on Retrospective Assessment of a Two Centre Cohort

Diagnostic accuracy of microvascular flow imaging ultrasound for endoleak detection after endovascular aortic aneurysm repair: a systematic review and meta-analysis

The objective was to assess the diagnostic accuracy of microvascular flow imaging ultrasound (MVUS) for the detection of endoleak after endovascular aortic aneurysm repair. A systematic search of the literature published until January 2024 was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses of Diagnostic Test Accuracy (PRISMA-DTA) guidelines. The pooled rates of sensitivity, specificity, and diagnostic odds ratio of MVUS in endoleak detection with computed tomography angiography as the reference standard were estimated using univariate random-effect analysis with 95% confidence intervals. Three studies were considered eligible for inclusion. Superb micro-vascular imaging (SMI) was used as an MVUS technique in all cases. The total number of paired scans was 209. Sensitivity and specificity of the individual studies ranged 0.75-1.00 and 0.93-1.00, respectively. Pooled sensitivity and specificity of the SMI method was 0.91 (CI: 0.82-0.96) and 0.98 (CI: 0.94-1.00), respectively. The pooled diagnostic odds ratio was 635 (95% CI: 128-3140). The findings of the present study support the use of the MVUS for endoleak detection. However, further research is warranted to explore the broader application of MVUS, providing a more comprehensive understanding and establishing robust criteria for its role in clinical practice.

Late post-EVAR abdominal aortic aneurysm rupture: a meta-analysis study

This study presents updated information on post-endovascular aneurysm repair (EVAR) late aortic rupture (LAR) as the data in the literature are limited. It comprises a meta-analysis based on the recent evidence regarding the incidence, causes, treatment outcomes, and prognosis of post-EVAR. A meta-analysis was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Studies were identified by searching electronic databases and scanning bibliographic references from 1991 to April 1, 2023. Our analysis provided evidence that the most common causes of rupture after EVAR were type Ia and Ib Endoleaks (Els). Post-rupture mortality after EVAR was high (35.6%) and comparable to the morbidity of de novo ruptures. Endovascular repair appears to have better results compared to conversion to open repair. A significant number of patients had prior endovascular reoperations and inadequate follow-up. Patient compliance with the surveillance protocol is mandatory.

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.

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.

Role of Contrast-Enhanced Ultrasound in the Follow-Up after Endovascular Abdominal Aortic Aneurysm Repair

Background: The aim of this study was to assess whether contrast-enhanced ultrasound (CEUS) shows a false negative rate close to zero and therefore is suitable as the main non-invasive follow-up strategy for long-term monitoring after endovascular aortic repair (EVAR). Methods: We included all consecutive patients who underwent CEUS as follow-up after EVAR at our center between January 2017 and December 2021.The follow-up protocol consisted of Duplex ultrasound (DUS) with CEUS at 1, 3, 6 months postoperatively and every 6 months thereafter. Results: A total of 125 patients underwent 228 CEUS. The aneurysm sac showed shrinkage in 80 (64%) patients, stability in 32 (25.6%), and enlargement in 13 (10.4%). A total of 29 (23.2%) patients showed type 2 endoleak, 6 (4.8%) patients showed type 1 endoleak and 3 (2.4%) patients showed type 3 endoleak. Thirteen patients underwent one or more reinterventions. The sensitivity of CEUS vs. DUS was 100% vs. 75% (p > 0.0001). In classifying type 2 endoleak, CEUS compared to DUS showed a sensitivity of 93.2% vs. 59.4% and a specificity of 99.3% vs. 99.3%. CEUS showed a higher sensitivity compared to DUS in the detection of type 2 endoleak. CEUS permits the identification of a subset of patients requiring a stricter follow-up protocol.

Colour Duplex and/or Contrast-Enhanced Ultrasound Compared with Computed Tomography Angiography for Endoleak Detection after Endovascular Abdominal Aortic Aneurysm Repair: A Systematic Review and Meta-Analysis

This study aims to assess the role of Color Duplex Ultrasound with or without contrast media for surveillance following endovascular aortic aneurysm repair (EVAR). A systematic search of the literature published until April 2022 was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The pooled rates of endoleak detection through Contrast-Enhanced or Color Duplex Ultrasound (CEUS or CDUS) and Computed Tomography Angiography (CTA) with 95% confidence intervals (CIs) were estimated using random-effect analysis. Thirty-eight studies were considered eligible for inclusion. The total number of patients in the included studies was 5214 between 1997 and 2021. The overall pooled rate of endoleak detection using CDUS and CTA was 82.59% and 97.22%, while the rates for CEUS and CTA were 96.67% and 92.82%, respectively. The findings of the present study support the use of the CEUS for endoleak detection. However, it should be integrated into institutional protocols for EVAR surveillance to further evaluate its clinical utility in the post-EVAR period before it can be recommended as the sole imaging modality after EVAR.

Prospective Multicentre Cohort Study of Fenestrated and Branched Endografts After Failed Endovascular Infrarenal Aortic Aneurysm Repair with Type Ia Endoleak

OBJECTIVE

Failed endovascular infrarenal aortic aneurysm repair (EVAR) due to development of late type Ia endoleak exposes patients to the risk of rupture and should be treated. The purpose of this study was to evaluate the results of fenestrated/branched EVAR (F/BEVAR) for treatment of failed EVAR with type Ia endoleak.

METHODS

From January 2010 to December 2019, a prospective multicentre study was conducted (ClinicalTrials.gov identifier: NCT04532450) that included 85 consecutive patients who had undergone F/BEVAR to treat a type Ia endoleak following EVAR. The primary outcome was overall freedom from any re-intervention or death related to the F/BEVAR procedure.

RESULTS

In 30 cases (35%) EVAR was associated with a short < 10 mm or angulated (> 60°) infrarenal aortic neck, poor placement of the initial stent graft (n = 3, 4%), sizing error (n = 2, 2%), and/or stent graft migration (n = 7, 8%). Type Ia endoleak was observed after a period of 59 ± 25 months following EVAR. The authors performed 82 FEVAR (96%) and three BEVAR (4%) procedures with revascularisation of 305 target arteries. Overall technical success was 94%, with three failures including one persistent Type Ia endoleak and two unsuccessful stent graft implantations. Intra-operative target artery revascularisation was successful in 303 of 305 attempts. The in hospital mortality rate was 5%. Cardiac, renal and pulmonary complications occurred in 6%, 14%, and 7% of patients, respectively. Post-operative spinal cord ischaemia occurred in four patients (4.7%). At three years, the survival rate was 64% with overall freedom from any re-intervention or aneurysm related death of 40%, and freedom from specific F/BEVAR re-intervention of 73%. At three years, the secondary patency rate of the target visceral arteries was 96%. During follow up, 27 patients (33%) required a revision procedure of the fenestrated (n = 11) or index EVAR stent graft (n = 16), including six open conversions.

CONCLUSION

While manufactured F/BEVAR was effective in treating type Ia endoleak in patients with failed EVAR, it was at the cost of a number of secondary endovascular and open surgical procedures.

Editor's Choice - A Comparison of Computed Tomography Angiography and Colour Duplex Ultrasound Surveillance Post Infrarenal Endovascular Aortic Aneurysm Repair: Financial Implications and Impact of Different International Surveillance Guidelines

OBJECTIVE

Use of colour duplex ultrasound (CDUS) and computed tomography angiography (CTA) for infrarenal endovascular aortic aneurysm repair (EVAR) surveillance differs in internationally published guidelines. This study aimed firstly to compare CDUS detection of significant sac abnormalities with CTA. Secondly, a sensitivity analysis was conducted to compare financial estimates of the, predominantly CDUS based, local and Society of Vascular Surgery (SVS) protocols, the risk stratified European Society of Vascular Surgery (ESVS) protocol, and the CTA based National Institute of Health and Care Excellence (NICE) protocol.

METHODS

Agreement between CDUS and CTA was assessed for detection of significant sac abnormalities. Surveillance protocols were extrapolated from published guidelines and applied to infrarenal EVAR patients active on local surveillance at a large, single centre. Surveillance intensity was dependent on presence of endoleak and subsequent risk of treatment failure in accordance with surveillance recommendations. Estimates for each surveillance protocol were inclusive of a range of published incidences of endoleak, contrast associated acute kidney injury (AKI), and excess hospital bed days, and estimated for a hypothetical five year surveillance period.

RESULTS

The kappa coefficient between CDUS and CTA for detecting sac abnormalities was 0.68. Maximum five year surveillance cost estimates for the 289 active EVAR patients were £272 359 for SVS, £230 708 for ESVS, £643 802 for NICE, and £266 777 for local protocols, or £1 270, £1 076, £3 003, and £1 244 per patient. Differences in endoleak incidence accounted for a 1.1 to 1.4 fold increase in costs. AKI incidence accounted for a 3.3 to 6.2 fold increase in costs.

CONCLUSION

A combined CTA and CDUS EVAR surveillance protocol, with CTA reserved for early seal assessment and confirmatory purposes, provides an economical approach without compromising detection of sac abnormalities. AKI, as opposed to direct imaging costs, accounted for the largest differences in surveillance cost estimates.

Assessment of EVAR Complications using CIRSE Complication Classification System in the UK Tertiary Referral Centre: A ∼6-Year Retrospective Analysis (2014-2019)

PURPOSE

To retrospectively analyse complications in endovascular aortic repair (EVAR) interventions and evaluate if the CIRSE (Cardiovascular and Interventional Radiological Society of Europe) complication classification system is appropriate as a standardized classification tool for EVAR patients.

MATERIALS AND METHODS

Demographic, procedural and complication data in 719 consecutive patients undergoing EVAR at one institution from January 2014 to October 2019 were retrospectively reviewed. Data (imaging reports, procedural reports, nurse notes, discharge summary reports) were collected consulting the electronic patient record system (EPR) of the hospital and cleaned and stored in a Microsoft Excel database. All the procedures were analysed in consensus by two interventional radiology consultants and a resident radiologist and if an intra- , peri- or post-procedural complication occurred, a grade (1-6) was assigned using the CIRSE grading complication classification system.

RESULTS

Twenty-five patients were excluded from the analysis because of invalid or incomplete data. The final population was made up of 694 patients (mean age 75,4 y.o., 616 male/78 female, min age 23 y.o., max age 97 y.o.). Complications emerged in 211 patients (30,4% of cases, 22 female/189 male). The number of patients with CIRSE grade I, II, III, IV, V and VI complications was 36 (17%), 17 (8%), 121 (57,3%), 15 (7,1%), 3 (1,4%), 19 (9%). Nineteen (2,6%) patients succumbed after EVAR. Thirty-four complications (16,1%) were related to vascular access.

CONCLUSION

The CIRSE complication classification system represents a broadly applicable and feasible approach to evaluate the severity of complications in patients following EVAR. However, some deficit may be considered relevant and as starting standing-point for future improvements.

Type II Endoleak Nidus Volume on Arterial and Delayed Phases of Initial CT Angiography after Endovascular Abdominal Aortic Aneurysm Repair Predicts Persistent Endoleak and Aneurysm Sac Enlargement

Purpose

To evaluate type II endoleak nidus volume (ENV) in the arterial phase (ENV_AP) and delayed phase (ENV_DP) of the first postoperative CT angiography (CTA) as a predictor of persistent endoleak and aneurysm sac enlargement at follow-up CTA in patients with endovascular aneurysm repair (EVAR) of abdominal aortic aneurysm.

Materials and Methods

Ninety-three patients (mean age ± standard deviation, 72 years ± 8; range, 56-88 years) with EVAR and type II endoleak were included in a single-institution retrospective study conducted between March 1, 2005, and December 31, 2018. ENV_AP, ENV_DP, change of volume (ENV_DP-AP), and percentage of ENV_AP and ENV_DP in aneurysm sac volume (ASV) (ENV_AP/ASV%, ENV_DP/ASV%, respectively) were measured on first postoperative CTA images. The mean follow-up was 31.6 months ± 26.6 (range, 6-163.8 months). Patients were divided into two groups (group A, spontaneous resolution of endoleak without intervention [n = 29] and group B, persistent endoleak at follow-up CTA [n = 64]) and compared by using the Mann-Whitney U, Wilcoxon signed rank, and Pearson χ² tests. Receiver operating characteristic (ROC) analysis was used to compare accuracies of parameters at first postoperative CTA.

Results

The accuracy of ENV_DP (area under the ROC curve [AUC], 0.78) was superior to the accuracy of ENV_DP/ASV% (AUC, 0.76), ENV_DP-AP (AUC, 0.74), ENV_AP (AUC, 0.71), and ENV_AP/ASV% (AUC, 0.69) in indicating persistent endoleak. In group B, 46 patients (72%) showed ASV enlargement and 44 patients (69%) underwent endoleak embolization. ENV_AP (1.7 cm³ ± 2.9 vs 3.4 cm³ ± 4.2; P = .001), ENV_DP (2.9 cm³ ± 3.8 vs 8.0 cm³ ± 9.6; P < .001), ENV_DP-AP (1.1 cm³ ± 1.8 vs 4.5 cm³ ± 7.8; P < .001), ENV_AP/ASV% (0.9% ± 1.5 vs 1.7% ± 2.2; P = .003), and ENV_DP/ASV% (1.6% ± 2.2 vs 3.7% ± 3.6; P < .001) were smaller in group A than in group B.

Conclusion

ENV_DP of the first postoperative CTA is an accurate predictor of persistent endoleak compared with ENV_AP, and persistent endoleak is associated with aneurysm sac enlargement, in which earlier intervention is recommended.© RSNA, 2021.