Treatment of visceral artery aneurysms and pseudoaneurysms with the use of cerebral flow diverting stents: initial experience

Endovascular Treatment of Visceral Artery Pseudoaneurysms with Ethylene-Vinyl Alcohol (EVOH) Copolymer-Based Non-Adhesive Liquid Embolic Agents (NALEAs)

Background and Objectives: Treatment of visceral artery pseudoaneurysms (VAPs) is always indicated regardless of their diameters, as their risk of rupture is significantly higher than that of visceral artery aneurysms. The invasiveness of surgery and its associated complications have led to a shift in favor of radiological interventions as the initial treatment of choice. However, there are still some unanswered questions on endovascular treatment of VAPs regarding the optimal endovascular technique and the efficacy and safety outcomes. The purpose of this multicenter study was to retrospectively evaluate the effectiveness and safety of endovascular treatment of visceral pseudoaneurysms using Ethylene-Vinyl Alcohol (EVOH) Copolymer-Based Non-Adhesive Liquid Embolic Agents (NALEAs). Materials and Methods: Consecutive patients who underwent endovascular embolization with EVOH-based NALEAs for visceral artery pseudoaneurysms between January 2018 and June 2023 were retrospectively evaluated. Results: 38 embolizations were performed. Technical success was achieved in all patients. The clinical success rate was high (92.1% overall), with no significant differences between ruptured and unruptured VAPs (p = 0.679). Seven patients (18.4%) experienced procedure-related complications, related to one case of non-target embolization, four splenic abscesses due to end-organ infarction, and two femoral pseudoaneurysms. The rates of procedure-related complications, end-organ infarction, and vascular access-site complications did not significantly differ between ruptured and unruptured VAPs (p > 0.05). Conclusions: Both ruptured and unruptured visceral pseudoaneurysms can be effectively and safely treated with NALEA-based endovascular embolization. We suggest considering the use of NALEAs, particularly in specific clinical cases that highlight their advantages, including patients with coagulopathy, fragile vessels, and embolization targets that are located at a considerable distance from the microcatheter tip and are otherwise difficult to reach.

Endovascular treatment of a wide-necked renal artery aneurysm with a flow diverter stent

Renal artery aneurysm (RAA) is a rare, often asymptomatic disease (0.1% incidence in general population) and can be incidentally diagnosed during an abdominal imaging workup. The traditional, gold standard of treatment is open surgery, carrying with it, however, a high risk of nephrectomy, mortality, and collateral morbidity. The endovascular approach is currently the most valid alternative to treating RAAs reducing, as it does, the risks associated with the surgical approach/open surgery. Herein we report on our experience with a case of wide-necked RAA treated with the Pipeline Vantage (Medtronic) flow diverter stent. Wide-neck aneurysms are defined as having neck diameters greater than 4 mm. Our choice of endovascular treatment was preferred over the surgical option notwithstanding the large size of the neck and the involvement of the branching vessels.

Splenic artery pathology presentation, operative interventions, and outcomes in 88 patients with Vascular Ehlers Danlos Syndrome

BACKGROUND

Vascular Ehlers-Danlos Syndrome (VEDS) is rare and associated with arteriopathies. The aim of this study is to investigate the presentation, operative interventions, and outcomes of splenic arterial pathology in a population of more than 1,500 individuals with genetically confirmed VEDS due to pathogenic COL3A1 variants.

METHODS

Cross-sectional analysis of 1,547 individuals was performed. The data were assembled by harmonizing data from three overlapping cohorts with genetically confirmed VEDS: the VEDS Collaborative Natural History Study (N=242), a single center cohort (N=75), and the UW Collagen Diagnostic Lab cohort (N=1,231). Duplicates were identified and removed. Patients were selected for analysis if they had splenic artery aneurysm (SAA), pseudoaneurysm, dissection, thrombosis, or rupture. Demographics, COL3A1 variants, interventions, and outcomes were analyzed. Comparisons by splenic artery rupture were made.

RESULTS

A total of 88 patients presented between 1992 and 2021 with splenic artery pathology (5.7% of the cohort, Mean age at diagnosis 37+11.1 years, 50% male). One third were diagnosed with VEDS prior to the splenic artery pathology diagnosis and 17% were diagnosed post-mortem. Most had a positive family history (61%). Most had COL3A1 variants associated with minimal normal collagen production (71.589.7%). Median follow up was 8.5 (IQR 0.9-14.7) years. Initial presentation was rupture in 47% of the cases. Splenic artery rupture overall was 51% (N=45) including 4 cases of splenic rupture. There were no major differences in VEDS related manifestations or COL3A1 variant type by rupture status. SAA was noted in 39% of the cases. Only 12 patients had splenic artery diameter documented in 12 cases with a median diameter of 12 (IQR 10.3-19.3) mm. A total of 34 (38.6%) patients underwent 40 splenic arterial interventions: 21 open surgical, 18 embolization, and 1 unknown procedure. More than one splenic artery intervention was performed in 5 (14.7%) cases. Open repair complications included arteriovenous fistula (n=1), intestinal or pancreatic injury (1 each), and four intraoperative deaths. There were no deaths or access site complications related to splenic artery embolization. Four (23.5%) developed a new SAA in the remaining splenic artery post embolization. All-cause mortality was 35% (n=31) including 22 related to a ruptured splenic artery.

CONCLUSIONS

Splenic arteriopathy in VEDS is associated with variants that affect the structure and secretion of type III collagen and frequently present with rupture. Rupture and open repair are associated with high morbidity and mortality while embolization is associated with favorable outcomes. Suggest repair considerations at SAA diameter of 15 mm. Long term follow up is indicated as secondary splenic arteriopathy can occur.

A case report: Retrograde arterial embolization of locally-injected SpaceOAR hydrogel material into the right common iliac artery bifurcation

Biodegradable hydrogel-based matrices are becoming more widely utilized for a variety of medical applications, including SpaceOAR which is a hydrogel injected into the recto-prostatic space under ultrasound guidance to protect the rectum during prostate radiation therapy. Although a greater number of these procedures are being performed, there are no case reports on the potential complications which may result. In this report, we present the first case of retrograde embolization of SpaceOAR hydrogel into the right common iliac artery during routine office administration, as well as subsequent interventional angiography, inpatient and outpatient management, and clinical and imaging results at 1.5-month patient follow-up.

Flow-diverter treatment for renal artery aneurysms: One-year follow-up of a multicentric preliminary experience

PURPOSE Renal artery aneurysms (RAAs) are rare in the general population, although the true incidence and natural history remain elusive. Conventional endovascular therapies such as coil embolization or covered stent graft may cause sidebranches occlusion, leading to organ infarction. Flow-diverters (FD) have been firstly designed to treat cerebrovascular aneurysms, but their use may be useful to treat complex RAAs presenting sidebraches arising from aneurysmal sac. To evaluate mid-term follow-up (FUP) safety and efficacy of FD during treatment of complex RAAs. METHODS Between November 2019 and April 2020, 7 RAAs were identified in 7 patients (4 men, 3 women; age range 55-82 years; median 67 years) and treated by FD. Procedural details, complications, morbidity and mortality, aneurysm occlusion and segmental artery patency were retrospectively reviewed. Twelve months computed tomography angiography (CTA) FUP was evaluated for all cases. RESULT Deployment of FD was successful in all cases. One intraprocedural technical complication was encountered with one FD felt down into aneurism sac which requiring additional telescopic stenting. One case at 3 months CTA FUP presented same complication, requiring same rescue technique. At 12 months CTA FUP 5 cases of size shrinkage and 2 cases of stable size were documented. No rescue surgery or major intraprocedural or mid-term FUP complication was seen. CONCLUSION Complex RAAs with two or more sidebranches can be safely treated by FD. FD efficacy for RAA needs a further validation at long term FUP by additional large prospective studies.

Single Centre Experience in Open and Endovascular Treatment of Renal Artery Aneurysms

BACKGROUND

The true incidence and natural history of renal artery aneurysm (RAA) remain unclear and still exists controversy over indication for treatment. Several techniques of conventional surgical reconstructions are described in literature, and more recently endovascular therapies have been reported with satisfying results and lower complication rate. This paper aims to investigate the outcomes of both endovascular and open repair of RAA achieved in a single institution involving 3 medical teams (urology, vascular surgery and neuroradiology).

MATERIAL AND METHODS

We conducted a single-centre retrospective observational study about all patients surgically or endovascularly treated for RAA over a 15-year period. Pre-operative, procedural and post-operative data at the early, mid- and long-term follow-up were collected and analysed, focusing on operative technique used for repair and related outcomes.

RESULTS

A total of 27 patients (n = 17 (63%) women, mean age 58 ± 13.2, n = 26 saccular RAA) were included. Mean aneurysm was size was 18.8 ± 6.3 mm. Most diagnosis were accidental. Symptomatic RAA showed with macroscopic haematuria (n = 3, 25.9%), unstable hypertension (n = 2; 7%), chronic lumbar pain (n = 1, 3.7%) and renal infarct (n = 1, 3.7%). Conventional surgery (ex-vivo repair, aneurysmorraphy, aneurysm resection and end-to-end anastomosis) was performed in 14 (51.8%) cases and endovascular coiling embolization in 13 (48.2%). Mean hospital length of stay was 5.4 ± 3.6 days. Intensive Care Unit stay was needed only in the surgically treated patients (mean 1.1 ± 1.2 days). During the early follow-up, morbidity rate was 7/14 in surgically treated patients vs. 1/13 in endovascular group; it included bleeding, retroperitoneal hematoma, arterial thrombosis and bowel obstruction. The discharge imaging showed complete aneurysm exclusion and renal artery patency in all cases. At a mean follow-up of 39 ± 42 months, 3 patients (11%) were lost to follow up and 2 (7.4 %) died from unrelated cause. None of these patients required dialysis but a statistically significant (P = 0.09) decrease in GFR was noted between the preoperative period and last follow-up control. RAA repair neither showed blood pressure control improvement nor reduced the need for anti-hypertensive drug use.

CONCLUSION

Open or endovascular techniques are both safe and efficient to treat RAA. Even though, surgical management is burdened with higher morbidity rate, the operative technique should be selected according to anatomical features, diameters and location of RRA; and the number of renal branches involved. Further larger studies are needed to define the feasibility and safety for a wider application of the endovascular approach.

Visceral Artery Aneurysms Embolization and Other Interventional Options: State of the Art and New Perspectives

Visceral artery aneurysms (VAAs) are rare, usually asymptomatic and incidentally discovered during a routine radiological examination. Shared guidelines suggest their treatment in the following conditions: VAAs with diameter larger than 2 cm, or 3 times exceeding the target artery; VAAs with a progressive growth of at least 0.5 cm per year; symptomatic or ruptured VAAs. Endovascular treatment, less burdened by morbidity and mortality than surgery, is generally the preferred option. Selection of the best strategy depends on the visceral artery involved, aneurysm characteristics, the clinical scenario and the operator's experience. Tortuosity of VAAs almost always makes embolization the only technically feasible option. The present narrative review reports state of the art and new perspectives on the main endovascular and other interventional options in the treatment of VAAs. Embolization techniques and materials, use of covered and flow-diverting stents and percutaneous approaches are accurately analyzed based on the current literature. Visceral artery-related considerations and targeted approaches are also provided and discussed.