Prophylactic Aneurysm Embolization during EVAR Is Safe, Improves Sac Regression and Decreases the Incidence of Type II Endoleak

Aortic aneurysm sac filling with AneuFix injectable polymer during endovascular aneurysm repair: feasibility and safety trial study protocol

INTRODUCTION

Type II endoleaks (T2ELs) following endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA) can lead to aneurysm growth, compromising the stent graft seal and risking rupture. Preventing these endoleaks during EVAR involves filling the AAA sac around the stent graft to exclude the aneurysm and block any arteries causing the endoleak. This study investigates the feasibility and safety of using AneuFix, a biocompatible injectable polymer developed by TripleMed (Geleen, the Netherlands), for aneurysmal sac filling during EVAR in high-risk T2EL patients.

METHODS AND ANALYSIS

A feasibility, single-arm, single-centre clinical trial will initially include five patients with infrarenal AAA, eligible for EVAR, and at high risk for T2EL based on the number of patent lumbar arteries and the cross-sectional area of the aortic lumen at the level of the inferior mesenteric artery. Postevaluation by the Data Safety and Monitoring Board, the study cohort will extend to 25 patients. During EVAR and after stent graft deployment, the aneurysm sac is filled with AneuFix polymer using a filling sheath positioned parallel to the contralateral limb with the tip inside the aneurysm sac. Primary outcome is technical success (successful AAA sac filling). The secondary outcomes include clinical success at 6 and 12 months (occurrence of T2ELs and AAA growth assessed with CT angiography), intraoperative and perioperative complications, all endoleaks, adverse events, re-interventions, aneurysm rupture and patient survival.

ETHICS AND DISSEMINATION

This trial was approved by the Dutch Authorities (Central Committee on Research Involving Human Subjects, IGJ), Amsterdam University Medical Centre Ethical Commission, and adheres to the Declaration of Helsinki and European Medical Device Regulation. Results will be shared at (inter)national conferences and in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT04307992.

Three-Dimensional Printing Application in a Challenging Case of Type II Endoleak

PURPOSE

To highlight the importance of 3-dimensional (3D) arterial printing in a case of type II endoleak (EL) embolization.

CASE REPORT

An 81-year-old patient, previously treated with endovascular aortic repair (EVAR), developed a type II EL requiring treatment. The EL's main origin was the median sacral artery (MSA). Initial attempts in embolization via a transsealing and transarterial approach were unsuccessful owing to extremely tortuous arterial communications between the left hypogastric artery and the MSA. The construction of a clear resin 3D model of the aorta and iliolumbar arteries improved anatomy understanding and moreover allowed a preoperative simulation. The subsequent transarterial attempt in embolization was resolutive, significantly reducing total procedural time and radiation dose.

CONCLUSION

Printing of clear resin 3D arterial models facilitates type II EL transarterial embolization, improving anatomy understanding and allowing simple fluoroscopy-free simulations.

CLINICAL IMPACT

The aim of our work is to highlight the additional value of three-dimensional (3D) printing during preoperative planning of challenging endovascular cases. To our best knowledge, this is the first report about 3D printing use in a case of type II endoleak (EL). We believe that realizing life-size aortic models in selected cases where a complex type II EL embolization procedure is indicated, could lead to a better understanding of arterial anatomy, thus allowing to increase procedural success and reduce operative and most importantly fluoroscopy time.

Selective aneurysmal sac neck-targeted embolization during endovascular repair of abdominal aortic aneurysm with hostile neck anatomy

PURPOSE

To evaluate the efficacy and safety of selective aneurysmal sac neck-targeted embolization in endovascular aneurysm repair (EVAR) in patients with a hostile neck anatomy (HNA).

MATERIALS AND METHODS

Between October 2020 and June 2022, patients with an abdominal aortic aneurysm (AAA) and HNA who underwent EVAR with a low-profile stent graft and a selective aneurysmal sac neck-targeted embolization technique were analysed. An HNA was defined by the presence of any of the following parameters: infrarenal neck angulation > 60°; neck length < 15 mm; conical neck; circumferential calcification ≥ 50%; or thrombus ≥ 50%. Before occluding the entire aneurysm during the procedure, a buddy wire was loaded prophylactically into the sac through the contralateral limb side. If a type Ia endoleak (ELIa) occurred and persisted despite adjunctive treatment such as balloon moulding or cuff extension, this preloaded wire could be utilized to enable a catheter to reach the space between the stent graft and sac neck to perform coil embolization. In the absence of ELIa, the wire was simply retracted. The primary outcome of this study was freedom from sac expansion and endoleak-related reintervention during the follow-up period; secondary outcomes included technical success and intraoperative and in-hospital postoperative complications.

RESULTS

Among the 28 patients with a hostile neck morphology, 11 (39.5%) who presented with ELIa underwent intraprocedural treatment involving sac neck-targeted detachable coil embolization. Seventeen individuals (60.7%) of the total patient population did not undergo coiling. All patients in the coiling group underwent balloon moulding, and 2 patients additionally underwent cuff extension. In the noncoiling group, 14 individuals underwent balloon moulding as a treatment for ELIa, while 3 patients did not exhibit ELIa during the procedure. The coiling group showed longer operating durations (81.27 ± 11.61 vs. 70.71 ± 7.17 min, P < 0.01) and greater contrast utilization than the noncoiling group (177.45 ± 52.41 vs. 108.24 ± 17.49 ml, P < 0.01). In the entire cohort, the technical success rate was 100%, and there were no procedure-related complications. At a mean follow-up of 18.6 ± 5.2 months (range 12-31), there were no cases of sac expansion (19 cases of sac regression, 67.86%; 9 cases of stability, 32.14%) or endoleak-related reintervention.

CONCLUSIONS

Selective aneurysmal sac neck-targeted embolization for the treatment of ELIa in AAA patients with an HNA undergoing EVAR is safe and may prevent type Ia endoleak and related sac expansion after EVAR.

Impact of patient demographics and intraoperative characteristics on abdominal aortic aneurysm sac following endovascular repair

BACKGROUND

Endovascular aortic repair (EVAR) has become the preferred treatment for abdominal aortic aneurysm (AAA). Its main aim is to seal the perfusion of the aneurysmal sac and, thus, induce sac regression and subsequent aortic remodelling. Aneurysmal sac regression has been linked to the short- and long-term clinical outcomes post-EVAR. It has also been shown to be influenced by endograft device choice, with several of these available commercially. This review summarises and discusses current evidence on the influence of pre- and intraoperative factors on sac regression. Additionally, this review aims to highlight the device-specific variations in sac regression to provide an overall holistic approach to treating AAAs with EVAR.

METHODS

A comprehensive literature search was conducted using multiple electronic databases to identify and extract relevant data.

RESULTS

Female sex, >70 mm original sac diameters, higher pre-procedural fibrinogen levels, smoking and low intra-aneurysmal pressure were found to positively impact sac regression. Whereas renal impairment, ischemic heart disease, high intra-aneurysmal pressure and aneurysm neck thrombus negatively influenced sac regression. Patent lumbar arteries, age, statins and hypercholesterolaemia displayed conflicting evidence regarding sac regression. Regarding the EVAR endografts compared, newer generation devices such as the Anaconda mainly showed the most optimal results.

CONCLUSION

Sac regression following EVAR in AAA is an important prognostic factor for morbidity and mortality. Nevertheless, several pre- and intraoperative factors can have an influence on sac regression. Therefore, it is necessary to take them into account when assessing AAA patients for EVAR to optimise outcomes. The choice of EVAR stent-graft can also affect sac regression, with evidence suggesting that the Fenestrated Anaconda is associated with the most favourable results.

Abdominal Aortic Aneurysm Shrinkage up to 2 Years Following Endovascular Repair with PEmbolization for Preventing Type 2 Endoleak: A Retrospective Single Center Study

BACKGROUND

The aim of the present study was to evaluate the efficacy of preemptive embolization of aneurysm side branches that cause type 2 endoleak (T2EL).

METHODS

We performed a retrospective review of consecutive patients who underwent endovascular aneurysm repair (EVAR) in our facility between April 2009 and April 2019. All the patients underwent the preemptive embolization for preventing T2EL since April 2014. The patients were divided into the nonembolization group (between April 2009 and May 2014) or the embolization group (between April 2014 and April 2019). We used a support wire to improve a success rate of the preemptive embolization. The aneurysm sac shrinkage (≧5 mm), freedom from all-cause death and aneurysm-related death, T2EL-related reinterventions, aneurysm sac enlargement (≧5 mm), and complications related to the endovascular procedure were compared between the 2 groups.

RESULTS

Two-hundred patients with abdominal aortic aneurysm were included. They were divided into the nonembolization group (N = 103) and the embolization group (N = 97). We successfully embolized 89% of all the patent aneurysm side branches in the embolization group. The characteristics of the 2 groups were similar except for hypertension, patent lumbar arteries, and the use of Zenith, Excluder, and Endurant. The preemptive embolization group showed better aneurysm sac shrinkage (73% vs. 42%; P < 0.0001), no aneurysm sac enlargement (0% vs. 5%; P < 0.05), and lower T2EL-related reintervention rate (hazard ratio, 0.11; 95% confidence interval, 0.0061-0.60; P < 0.01) up to 2 years after EVAR. There were no significant differences in freedom from all-cause death, aneurysm-related death, and complications between the 2 groups.

CONCLUSIONS

The present study showed the high success rate of preemptive embolization of aneurysm side branches resulting in better anatomical changes in the aneurysm sac and lower T2EL-related intervention rate in the embolization group up to 2 years after EVAR.

Systematic review and network meta-analysis of pre-emptive embolization of the aneurysm sac side branches and aneurysm sac coil embolization to improve the outcomes of endovascular aneurysm repair

Objective

Previous reports have revealed a high incidence of type II endoleak (T2EL) after endovascular aneurysm repair (EVAR). The incidence of T2EL after EVAR is reduced by pre-emptive embolization of aneurysm sac side branches (ASSB) and aneurysm sac coil embolization (ASCE). This study aimed to investigate whether different preventive interventions for T2EL were correlated with suppression of aneurysm sac expansion and reduction of the re-intervention rate.

Methods

The PubMed, Web of Science, MEDLINE and Embase databases, and conference proceedings were searched to identify articles on EVAR with or without embolization. The study was developed in line with the Participants, Interventions, Comparisons, Outcomes, and Study design principles and was conducted and reported in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. We used network meta-analysis based on multivariate random-effects meta-analysis to indirectly compare outcomes of different strategies for embolization during EVAR.

Results

A total of 31 studies met all inclusion criteria and were included in the qualitative and quantitative syntheses. The included studies were published between 2001 and 2022 and analyzed a total of 18,542 patients, including 1,882 patients who received prophylactic embolization treatment during EVAR (experimental group) and 16,660 who did not receive prophylactic embolization during EVAR (control group). The effect of pre-emptive embolization of the inferior mesenteric artery (IMA) (IMA-ASSB) in preventing T2EL was similar (relative risk [RR] 1.01, 95% confidence interval [CI] 0.38–2.63) to the effects of non-selective embolization of ASSB (NS-ASSB) and ASCE (RR 0.88, 95% CI 0.40–1.96). IMA-ASSB showed a better clinical effect in suppressing the aneurysm sac expansion (RR 0.27, 95% CI 0.09–2.25 compared with NS-ASSB; RR 0.93, 95% CI 0.16–5.56 compared with ASCE) and reducing the re-intervention rate (RR 0.34, 95% CI 0.08–1.53 compared with NS-ASSB; RR 0.66, 95% CI 0.19–2.22 compared with ASCE). All prophylactic embolization strategies improved the clinical outcomes of EVAR.

Conclusion

Prophylactic embolization during EVAR effectively prevents T2EL, suppresses the aneurysm sac expansion, and reduces the re-intervention rate. IMA embolization demonstrated benefits in achieving long-term aneurysm sac stability and lowering the risk of secondary surgery. NS-ASSB more effectively reduces the incidence of T2EL, while IMA embolization alone or in combination with ASCE enhances the clinical benefits of EVAR. In addition, as network meta-analysis is still an indirect method based on a refinement of existing data, more studies and evidence are still needed in the future to establish more credible conclusions.

[The Prophylaxis of Type 2 Endoleaks is Relevant for Long Term Success of EVAR]

One out of 8 patients needs a reintervention after EVAR during the first 5 years. Two thirds of secondary interventions aim at treating endoleaks. The prevalence of complications doubles in the presence of endoleaks. Fourth generation stent grafts do not lead to a decrease in Type 2-associated reinterventions, but to better prevention of Type 1 and 3 endoleaks. Pretreatment of potential type 2 feeding arteries with embolising agents and treatment of the occurrence of type 2 endoleaks.