Tailored Sac Embolization During EVAR for Preventing Persistent Type II Endoleak

An Expert-Based Review on the Relevance and Management of Type 2 Endoleaks Following Endovascular Repair of Ruptured Abdominal Aortic Aneurysms

Ruptured abdominal aortic aneurysms (rAAAs) are life-threatening and require emergent surgical therapy. Endovascular aortic repair for rupture (rEVAR) has become the leading strategy due to its minimal invasive approach with expected lower morbidity and mortality, especially in patients presenting with hemodynamic instability and relevant comorbidities. Following rEVAR, intraoperative angiography or early postinterventional computed tomography angiography have to exclude early type 1 or 3 endoleaks requiring immediate reintervention. Persistent type 2 endoleaks (T2ELs) after rEVAR, in contrast to elective cases, can cause possibly lethal situations due to continuing extravascular blood loss through the remaining aortic aneurysm rupture site. Therefore, early identification of relevant persistent T2ELs associated with continuous bleeding and hemodynamic instability and immediate management is mandatory in the acute postoperative setting following rEVAR. Different techniques and concepts for the occlusion of T2ELs after rEVAR are available, and most of them are also used for relevant T2ELs after elective EVAR. In addition to various interventional embolization procedures for persistent T2ELs, some patients require open surgical occlusion of T2EL-feeding arteries, abdominal compartment decompression or direct surgical patch occlusion of the aneurysm rupture site after rEVAR. So far, in the acute situation of rAAAs, indications for preemptive or intraoperative T2EL embolization during rEVAR have not been established. In the long term, persistent T2ELs after rEVAR can lead to continuous aneurysm expansion with the possible development of secondary proximal type I endoleaks and an increased risk of re-rupture requiring regular follow-up and early consideration for reintervention. To date, only very few studies have investigated T2ELs after rEVAR or compared outcomes with those from elective EVAR regarding the special aspects of persisting T2ELs. This narrative review is intended to present the current knowledge on the incidence, natural history, relevance and strategies for T2EL management after rEVAR.

Type II endoleaks after fenestrated/branched endografting for juxtarenal and pararenal aortic aneurysms

OBJECTIVE

Persistent type II endoleaks (pEL2s) are not uncommon after endovascular aneurysm repair and their impact on long-term outcomes is well-documented. However, their occurrence and natural history after fenestrated/branched endografting (F/B-EVAR) for juxtarenal and pararenal aneurysms (J/P-AAAs) have been scarcely investigated. Aim of this study was to report incidence, risk factors, and natural history of pEL2 after F/B-EVAR in J/P-AAAs.

METHODS

Between 2016 and 2022, all J/P-AAAs undergoing F/B-EVAR were prospectively collected and retrospectively analyzed. EL2 were assessed at the completion angiography, at 30 days and after 6 months as primary outcomes. Preoperative risk factors for pEL2, follow-up survival, freedom from reinterventions (FFR) and aneurysm shrinkage (≥5 mm) were considered as secondary outcomes.

RESULTS

Of 132 patients, there were 88 (67%) JAAAs and 44 (33%) PAAAs. Seventeen EL2 (13%) were detected at the completion angiography and 36 (27%) at 30-day computed tomography angiography. The mean follow-up was 28 ± 23 months. Eleven (31%) EL2 sealed spontaneously within 6 months and three new cases were detected, for an overall of 28 pEL2/107 patients (26%) with available radiological follow-up of ≥6 months. Preoperative antiplatelet therapy (odds ratio, 4.7; 95% confidence interval [CI[, 1-22.1; P = .05), aneurysm thrombus volume of ≤40% and six or more patent aneurysm afferent vessels (odds ratio, 7.2; 95% CI, 1.8-29.1; P = .005) were independent risk factors for pEL2. The estimated 3-year survival was 80%, with no difference between cases with and without pEL2 (78% vs 85%; P = .08). The estimated 3-year FFR was 86%, with no difference between cases with and without pEL2 (81% vs 87%; P = .41). Four cases (3%) of EL2-related reinterventions were performed. In 65 cases (49%), aneurysm shrinkage was detected. pEL2 was an independent risk factor for absence of aneurysm shrinkage during follow-up (hazard ratio, 3.2; 95% CI, 1.2-8.3; P = .014). Patients without shrinkage had lower follow-up survival (64% vs 86% at 3-year; P = .009) and FFR (74% vs 90% at 3 years; P = .014) than patients with shrinkage.

CONCLUSIONS

PEL2 is not infrequent (26%) after F/B-EVAR for J/P-AAAs and is correlated with preoperative antiplatelet therapy, aneurysm thrombus volume of ≤40%, and six or more patent sac afferent vessels. Patients with pEL2 have a diminished aneurysm shrinkage, which is correlated with lower follow-up survival and FFR compared with patients with aneurysm shrinkage.

Pre-emptive False Lumen Embolization to Prevent Persistent Type II Endoleak in Fenestrated-Branched Endovascular Repair of Post-Dissection Thoracoabdominal Aortic Aneurysms

PURPOSE

The purpose was to describe a technique to promote false lumen (FL) thrombosis in post-dissection thoracoabdominal aortic aneurysms (PD-TAAAs) managed by fenestrated/branched endografting (F/B-EVAR).

TECHNIQUE

A 5/6Fr-90 cm length sheath is advanced from the true lumen (TL) to FL through the most distal entry tear of the infrarenal aorta or iliac arteries. It is parked in the most cranial portion of the FL in the thoracic aorta. Aortic endografts are deployed in the TL excluding all the para-visceral/distal entry tears and target visceral vessels bridging stenting is performed. A selective FL angiography is performed through the 5/6Fr sheath to detect the origin of all segmentary arteries. Embolization of FL is performed from above to below by M-reye pushable coils, obtaining the packaging of FL. After completion angiography, the 5/6Fr sheath is retrieved in external iliac artery and molding ballooning of the distal segment of the aortic/iliac endograft is performed. Between 2019 and 2023, this technique was applied in 11cases with a median number of 73 (interquartile range [IQR=12) coils. Out of 8 (72%) patients with available radiological follow-up at 1 year, 7 exhibited complete FL thrombosis.

CONCLUSIONS

The FL coiling in PD-TAAAs managed by F/B-EVAR is feasible, safe, and effective to promote the complete FL thrombosis.

CLINICAL IMPACT

Preemptive false lumen embolization is a feasible, safe, and effective technique for preventing persistent type II endoleaks after fenestrated-branched endovascular repair of post-dissection thoracoabdominal aortic aneurysms. This technique may be routinely recommended to promote FL thrombosis and aortic remodeling after FB-EVAR in PD-TAAAs, thereby reducing the incidence of reinterventions during follow-up.

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.

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.

Endovascular Treatment of Abdominal Aortic Aneurysm With Severe Angulation of Infrarenal Aortic Neck by Gore Conformable Endograft

INTRODUCTION

The aim of the study is to report a single-center experience with the Gore Excluder conformable endograft with active control system (CEXC Device, W.L. Gore and Associates, Flagstaff, AZ, USA) in abdominal aortic aneurysms (AAAs) with severe infrarenal neck angulation.

METHODS

All patients underwent EVAR with CEXC Device between September 2018 and 2020, were prospectively enrolled, and retrospectively analyzed. Anatomical details of the proximal aortic neck were evaluated. Early endpoints were the use of repositionability and angulation system, intraoperative unplanned cuff, technical success (TS), 30-day morbidity/mortality, and reintervention. Follow-up endpoints were type-I endoleaks, endograft migration, aortic neck dilatation, aneurismal sac shrinkage, survival (S), and freedom from reintervention (FFR).

RESULTS

Twenty-five patients were enrolled (median age: 80 [range = 60-90] years, median AAA diameter: 60 [range = 52-90] mm). All patients had severe infrarenal neck angulation (beta angle ≧ 60°), and 11 (44%) of those had neck beta angle ≧ 90°. Median infrarenal neck angle, length, and diameter were 70° (range = 60°-90°), 22 (range = 13-42) mm and 22 (range = 18-31) mm, respectively. Endograft repositioning system was employed in 15 (60%) cases and the median number of repositioning maneuvers was 1 (range:0-4). Active angulation system was used in 17 (68%) patients. The median proximal diameter of the main-body and oversize were 28 (range = 23-36) mm and 28% (range = 21%-38%), respectively. Proximal cuff was positioned in 1 (4%) patient. Technical success was achieved in all cases. Intraoperative and perioperative morbidity and mortality were 12% and 0%, respectively. Perioperative type-I/III and II endoleaks were observed in 0 and 4 (16%) patients, respectively. The median follow-up was 12 months (range: 3-30). One patient died at 12-month for AAA-unrelated causes. Abdominal aortic aneurysm-sac shrinkage and stability were observed in 9 (36%) and 15 (60%) cases, respectively. No type-I/III endoleak and reintervention occurred during the follow-up. One persistent type-II endoleak was observed. Estimated survival at 24 months was 92%.

CONCLUSION

According to the present data, the CEXC Device allows an excellent rate of TS in severe angulated aortic neck. This preliminary data, could increase the rate of patients eligible for EVAR.