Early and midterm outcomes after transcatheter embolization of type I endoleaks in 25 patients

OnyxTMGel or Coil versus Hydrogel as Embolic Agents in Endovascular Applications: Review of the Literature and Case Series

This review focuses on the use of conventional gel or coil and "new" generation hydrogel used as an embolic agent in endovascular applications. In general, embolic agents have deep or multidistrict vascular penetration properties as they ensure complete occlusion of vessels by exploiting the patient's coagulation system, which recognises them as substances foreign to the body, thus triggering the coagulation cascade. This is why they are widely used in the treatment of endovascular corrections (EV repair), arteriovenous malformations (AVM), endoleaks (E), visceral aneurysms or pseudo-aneurysms, and embolisation of pre-surgical or post-surgical (iatrogenic) lesions. Conventional gels such as Onyx or coils are now commercially available, both of which are frequently used in endovascular interventional procedures, as they are minimally invasive and have numerous advantages over conventional open repair (OR) surgery. Recently, these agents have been modified and optimised to develop new embolic substances in the form of hydrogels based on alginate, chitosan, fibroin and other polymers to ensure embolisation through phase transition phenomena. The main aim of this work was to expand on the data already known in the literature concerning the application of these devices in the endovascular field, focusing on the advantages, disadvantages and safety profiles of conventional and innovative embolic agents and also through some clinical cases reported. The clinical case series concerns the correction and exclusion of endoleak type I or type II appeared after an endovascular procedure of exclusion of aneurysmal abdominal aortic (EVAR) with a coil (coil penumbra released by a LANTERN microcatheter), the exclusion of renal arterial malformation (MAV) with a coil (penumbra coil released by a LANTERN microcatheter) and the correction of endoleak through the application of Onyx 18 in the arteries where sealing by the endoprosthesis was not guaranteed.

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.

CIRSE Standards of Practice on Management of Endoleaks Following Endovascular Aneurysm Repair

BACKGROUND

Endoleaks represent the most common complication after EVAR. Some types are associated with ongoing risk of aneurysm rupture and necessitate long-term surveillance and secondary interventions.

PURPOSE

This document, as with all CIRSE Standards of Practice documents, will recommend a reasonable approach to best practices of managing endoleaks. This will include imaging diagnosis, surveillance, indications for intervention, endovascular treatments and their outcomes. Our purpose is to provide recommendations based on up-to-date evidence, updating the guidelines previously published on this topic in 2013.

METHODS

The writing group was established by the CIRSE Standards of Practice Committee and consisted of clinicians with internationally recognised expertise in endoleak management. The writing group reviewed the existing literature performing a pragmatic evidence search using PubMed to select publications in English and relating to human subjects up to 2023. The final recommendations were formulated through consensus.

RESULTS

Endoleaks may compromise durability of the aortic repair, and long-term imaging surveillance is necessary for early detection and correct classification to guide potential re-intervention. The majority of endoleaks that require treatment can be managed using endovascular techniques. This Standards of Practice document provides up-to-date recommendations for the safe management of endoleaks.

Liquid Embolic Agents for Endovascular Embolization: A Review

Endovascular embolization (EE) has been used for the treatment of blood vessel abnormalities, including aneurysms, AVMs, tumors, etc. The aim of this process is to occlude the affected vessel using biocompatible embolic agents. Two types of embolic agents, solid and liquid, are used for endovascular embolization. Liquid embolic agents are usually injectable and delivered into the vascular malformation sites using a catheter guided by X-ray imaging (i.e., angiography). After injection, the liquid embolic agent transforms into a solid implant in situ based on a variety of mechanisms, including polymerization, precipitation, and cross-linking, through ionic or thermal process. Until now, several polymers have been designed successfully for the development of liquid embolic agents. Both natural and synthetic polymers have been used for this purpose. In this review, we discuss embolization procedures with liquid embolic agents in different clinical applications, as well as in pre-clinical research studies.

Feasibility of aortic aneurysm sac embolization using a novel shape memory polymer embolic device

BACKGROUND

We investigated the feasibility of aneurysm sac embolization using a novel self-expanding porous shape memory polymer (SMP) device during endovascular aortic abdominal or thoracic aneurysm repair (EVAR).

METHODS

Retrospective analysis of consecutive patients treated at 2 centers in Germany. Patients were treated from January 2019 to July 2021 with follow-up at 7 days and 3, 6, and 12 months. Aneurysm sacs were implanted with SMP devices immediately following endograft placement during the same procedure. Primary endpoint was technically successful SMP-device deployment into the aneurysm sac outside the endograft. Secondary endpoints were changes in aneurysm volume and associated complications (e.g., endoleaks).

RESULTS

We included 18 patients (16 males), aged 72 ± 9 years, achieving 100% technical success. Mean preprocedure aortic aneurysm sac volume was 195 ± 117 mL with a perfused aneurysm volume of 97 ± 60 mL. A mean of 24 ± 12 SMP devices per patient were used (range 5-45, corresponding to 6.25-56.25 mL expanded embolic material volume). All evaluable patients exhibited sac regression except 2 patients yet to reach 3-month follow-up. At mean 11 ± 7 months (range 3-24), change in aneurysm volume from baseline was -30 ± 21 mL (p < 0.001). In 8 patients, aneurysm regression was observed despite type 2 endoleaks in 6 and type 1A endoleaks in 2, none of them requiring further intervention to date. No morbidity or mortality related to this treatment occurred.

CONCLUSIONS

SMP devices for aortic aneurysm sac embolization during endovascular repair appear feasible and safe in this small case series. Prospective studies are needed.

KEY POINTS

• Shape memory polymer is a novel, self-expanding, porous, and radiolucent embolic device material. • Aortic aneurysm sacs were treated with polymer devices immediately following endograft placement. • Aortic aneurysm sac regression was observed in all patients with over 3-month follow-up. • Aortic aneurysm sac regression was observed even in the presence of endoleaks.

Long-Term Outcomes Following Transarterial Embolisation of Proximal Type I Endoleaks Post-EVAR

PURPOSE

To describe the long-term outcomes following transarterial embolisation for type Ia endoleaks (ELIa) in patients who failed or were unsuitable for standard endovascular/surgical options.

MATERIALS AND METHODS

A retrospective single-centre observational study was performed between October 2010 and April 2018. Technical success rates and long-term outcomes were evaluated. A sub-analysis was performed comparing outcomes of covered aortic endografts and Nellix endovascular aneurysm sealing systems.

RESULTS

A total of 34 transcatheter embolisations were performed for ELIa in 27 patients (13 endografts and 14 patients with Nellix systems). A combination of Onyx and coils was used most frequently (18/34), followed by Onyx alone (14/34) and coils alone (2/34). Technical success was achieved in 33/34 (97%) procedures . Seven early complications occurred with no immediate mortality, 5 of which involved migration/reflux of embolic into the endograft-all successfully managed via endovascular approach. Following the surveillance period (mean 25 months), 13/26 (50%) of patients were free from recurrent endoleak. Sac expansion occurred in 42% (11/26). 21/26 patients died; 6 due to aneurysm sac rupture, 10 due to unrelated causes, and 5 had no cause of death available. No significant difference in survival was found between patients with an endograft or Nellix graft-Chi-squared value - 0.011 (p < 0.05 = 3.84).

CONCLUSIONS

Transcatheter embolisation for type Ia endoleaks is a safe and effective option in a select patient cohort-where traditional endovascular and surgical options are unsuitable or have failed. The procedure may prevent recurrence in some whilst delaying rupture and death in others.

Midterm Outcomes of Endoleak Type 2 Embolization after Endovascular Aortic Aneurysm Repair Using a Neurointerventional Approach

BACKGROUND

Type 2 endoleaks (T2ELs) have been considered a benign condition and intervention is recommended when they are associated to sac expansion. The aim of this study was to report on T2EL embolization midterm outcomes, using neurointerventional material.

METHODS

A single-center retrospective analysis of consecutive patients treated with transarterial embolization, using neurointerventional material, for T2EL after standard endovascular aortic aneurysm repair (EVAR) between January 01, 2017 and July 30, 2022, was undertaken. Primary outcome was technical success and secondary outcome was T2EL recurrence during follow-up.

RESULTS

Twenty six patients [92.3% males, mean age 73.9 ± 7.7 years] were included. The median time between EVAR and T2EL diagnosis was 12 months (range: 1-84 months). In 38.5% of patients, T2EL was detected at first month after EVAR. The time to embolization was 18 months (range: 1-96 months). In 42.3% of cases, a patent inferior mesenteric artery was suspected to relate to T2EL formation while in 42.3% of cases, a lumbar artery. Twelve procedures (38.4%) were performed using coils and Onyx and 13 (50%), using only Onyx. Technical success was 84.6%. The mean follow-up was 24 months (range: 1-60 months), including 20 patients. In 30% of cases, an T2EL recurrence was detected. Three patients (11.5%) underwent secondary embolization.

CONCLUSIONS

Transarterial embolization for T2EL, using neurointerventional material, provided acceptable technical success and T2EL recurrence rates at 2 years of follow-up. Longer follow-up data would further estimate the durability of the technique.

Embolization for Type Ia Endoleak after EVAR for Abdominal Aortic Aneurysms: A Systematic Review of the Literature

(1) Successful endovascular repair for abdominal aortic aneurysms is based on the complete exclusion of the aneurysm sac from the systemic circulation. Type Ia endoleak (ELIA) is defined as the persistent perfusion of the aneurysm sac due to incomplete proximal sealing between aorta and endograft, with a consequent risk of rupture and death. Endoleak embolization has been sporadically reported as a viable treatment for ELIA. (2) A systematic literature search in PubMed of all publications in English about ELIA embolization was performed until February 2022. Research methods and reporting were performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Data regarding patient numbers, technical success (endoleak absence at control angiography), reinterventions, clinical and imaging follow-up, and outcomes were collected and examined by two independent authors. (3) Twenty-one papers (12 original articles, 9 case reports) reported on 126 patients (age range 58-96 years) undergoing ELIA embolization 0-139 months after the index procedure. Indication for embolization was most often founded on unfavorable anatomy and patient comorbidities. Embolic agents used include liquid embolic agents, coils, plugs and combinations thereof. Technical success in this highly selected cohort ranged from 67-100%; the postprocedural complication rate within 30 days was 0-24%. ELIA recurrence was reported as 0-42.8%, with a secondary ELIA-embolization-intervention success rate of 50-100%. At a follow-up at 0-68 months, freedom from sac enlargement amounted to 76-100%, freedom from ELIA to 66.7-100%. (4) Specific literature about ELIA embolization is scant. ELIA embolization is a valuable bailout strategy for no-option patients; the immediate technical success rate is high and midterm and long-term outcomes are acceptable.

A Case of Late Type Ia Endoleak After Endovascular Aneurysm Sealing Using the Nellix System: Proximal Extension with Triple Chimney and Gutter Endoleak Embolization

An 87-year-old man, who submitted to endovascular aneurysm sealing (EVAS) on 2017, presented a type Ia endoleak 2 years later, with enlargement of the aneurysmal sac. We planned an endovascular procedure of correction consisting of a proximal extension through two covered stent grafts deployed into the previous Nellix stent grafts, with associated triple chimney. However, 3 months later, he had a further 5 mm aneurysmal sac enlargement. He was submitted to angiography with coil embolization of gutters, obtaining a successfully result. At 1 and 3 months, he is free from endoleak, with a stable aneurysmal diameter.

Systematic review of embolization of type I endoleaks using liquid embolic agents

OBJECTIVE

The long-term success of endovascular aneurysm repair (EVAR) is limited by complications, most importantly endoleaks. In case of (persistent) type I endoleak (T1EL), secondary intervention is indicated to prevent secondary aneurysm rupture. Different treatment options are suggested for T1ELs, such as endo anchors, (fenestrated) cuffs, embolization, or open conversion. Currently, the treatment of T1EL with liquid embolic agents is available; however, results are not yet addressed. This review presents the safety and efficacy of embolization with liquid embolic agents for treatment of T1ELs after EVAR.

METHODS

A systematic literature search was performed for all studies reporting the use of liquid embolic agents as monotherapy for treatment of T1ELs after EVAR. Patient numbers, technical success (successful delivery of liquid embolics in the T1EL) and clinical success (absence of aneurysm related death, endoleak recurrence or additional interventions during follow-up) were examined.

RESULTS

Of 1604 articles, 10 studies met the selection criteria, including 194 patients treated with liquid embolics; 73.2% of the patients were male with a median age of 71 years. The overall technical success was 97.9%. Clinical success was 87.6%. Because the median follow-up was only 13.0 months (range, 1-89 months), data on long-term success are almost absent. Four cases (2.1%) of secondary aneurysm rupture after embolization owing to endoleak recurrence were reported. All ruptures occurred in aneurysms exceeding initial treatment diameter of 70 mm.

CONCLUSIONS

Initial technical success after liquid embolization for T1EL is high, although long-term clinical success rates are lacking. Within this review, the risk of secondary rupture is comparable with untreated T1EL at 2% with a median follow-up of 13 months, regardless of the initial success of embolization. In general, no decrease in secondary aneurysm rupture after embolization of T1EL after EVAR is demonstrated, although the results of late embolization are debated.

Novel Technique for the Treatment of Type Ia Endoleak After Endovascular Abdominal Aortic Aneurysm Repair

Purpose

Open surgical repair of type Ia endoleak after endovascular aortic aneurysm repair/sealing (EVAR/EVAS) is associated with significant perioperative mortality and morbidity. Current endovascular redo techniques face limitations, especially when the infrarenal landing zone is inadequate and the previous endograft is rigid and features a short or no main body. We present a novel concept for the treatment of type Ia endoleak using a custom-made branched device.

Technique

The 5-branch-device (Cook Medical, Bloomington, IN, USA) consists of a nitinol skeleton with branches, covered with a low-profile polyester fabric loaded in an 18F sheath. The device features a minimum of 2 proximal sealing stents and includes branches for renovisceral vessels as well as an additional 8 mm branch for the contralateral iliac limb. Implantation and sealing in the renovisceral vessels is carried out in standard fashion, using transfemoral and transaxillary access. Distal sealing is achieved by tapering the branched component into the ipsilateral iliac limb and using a bridging balloon-expandable or self-expandable stent-graft through the additional branch to the preexisting contralateral iliac limb.

Conclusion

Treatment of type Ia endoleak with a new custom-made device enables sufficient proximal seal while minimizing suprarenal aortic coverage and facilitates adequate component overlap. The low profile branched design accommodates implantation through the preexisting endograft and catheterization of target vessels.

Secondary Endoleak Management Following TEVAR and EVAR

Endovascular abdominal and thoracic aortic aneurysm repair and are widely used to treat increasingly complex aneurysms. Secondary endoleaks, defined as those detected more than 30 days after the procedure and after previous negative imaging, remain a challenge for aortic specialists, conferring a need for long-term surveillance and reintervention. Endoleaks are classified on the basis of their anatomic site and aetiology. Type 1 and type 2 endoleaks (EL1 and EL2) are the most common endoleaks necessitating intervention. The management of these requires an understanding of their mechanics, and the risk of sac enlargement and rupture due to increased sac pressure. Endovascular techniques are the main treatment approach to manage secondary endoleaks. However, surgery should be considered where endovascular treatments fail to arrest aneurysm growth. This chapter reviews the aetiology, significance, management strategy and techniques for different endoleak types.

Endovascular approach to arterial branches mimicking a type II endoleak after popliteal artery aneurysm exclusion and bypass

The management of popliteal artery aneurysms (PAAs) has continued to evolve. Open surgical treatment remains an excellent option. Aneurysm exclusion with saphenous vein bypass through a medial incision remains a preferred approach. After PAA exclusion, however, a possibility remains of sac expansion from geniculate arterial branches. This can mimic a type II endoleak occurring after endovascular aortic aneurysm repair. In the present report, we have described an endovascular technique used to treat an enlarging PAA after exclusion and bypass.

Evolving Concepts, Management, and Treatment of Type 1 Endoleaks after Endovascular Aneurysm Repair

Over the past 20 years, there has been tremendous progress in endovascular aneurysm repair techniques and devices. The application of new third- and fourth-generation devices (from 2003 onward) has led to changes in the incidence and management of endoleaks. This comprehensive review aims to outline the most recent concepts with respect to pathophysiology/risk factors and management of Type 1 endoleaks.

Evolving concepts and management of endoleaks after endovascular aneurysm repair: where do we stand in 2019?

In recent years, there has been tremendous progress in endovascular aneurysm repair (EVAR) techniques and devices. This process has seen a change in incidence, risk factors, and treatment of endoleaks as well as in follow-up protocols after EVAR. In particular, recent literature has highlighted new concepts in the evaluation and prevention/treatment of type I and II endoleak after standard EVAR. There is also recent evidence regarding new imaging protocols for follow-up after EVAR, which include magnetic resonance imaging and contrast-enhanced ultrasound. This comprehensive review aims to outline the most recent concepts on imaging follow-up, pathophysiology/risk factors, and management of endoleaks.

Stent Graft Implantation and Superselective Embolization with Liquid Embolic Agent, Onyx for Iatrogenic Common Iliac Artery Pseudoaneurysm and Persistant Endoleak

A 68-year-old male patient with a history of femoro-femoral bypass following unsuccessful intervention for chronic total iliac occlusion was found to have a saccular pseudoaneurysm of the right common iliac artery (CIA) due to interventional device-related injuries associated with the past endovascular intervention. An iatrogenic pseudoaneurysm in the CIA is generally asymptomatic, but it has a high risk of rupture, regardless of its size or symptoms. Endovascular therapy may be the best treatment option; however, ineffective sealing with a stent graft may lead to a type I endoleak. Under such conditions, use of the liquid embolic agent, Onyx, as a bailout solution for the type 1 endoleak is promising.

Effectiveness of Intra-Arterial Aneurysm Sac Embolization for Type Ia Endoleak after Endovascular Aneurysm Repair

PURPOSE

To evaluate the effectiveness and durability of intra-arterial aneurysm sac embolization for the treatment of type Ia endoleak after endovascular aneurysm repair (EVAR).

MATERIALS AND METHODS

From February 2011 to December 2016, 22 patients underwent embolization of a type Ia endoleak after EVAR. Four patients (18%) were treated during the index EVAR and 18 (82%) in follow-up. Five patients (23%) were treated urgently and 17 (77%) electively. The embolization was performed with the use of liquid embolic agent, coils, and/or plugs. Adjunctive neck procedures were performed in 55% (n = 12) of the patients. The primary endpoint of this study was freedom from sac enlargement. Key secondary endpoints were technical success and freedom from endoleak-related reinterventions.

RESULTS

Technical success was 100%. The 30-day mortality was 5% (n = 1; acute coronary syndrome). At a mean follow-up of 15.4 months (range 0.1-65.4) the freedom from sac enlargement rate was 76% (16 out of 21). Reintervention-free survival rates at 6, 12, and 24 months were 80%, 68% and 68%, respectively.

CONCLUSIONS

In patients with persistent type Ia endoleak the embolization of the aneurysm sac with or without adjunctive neck procedures can be safely performed, leading to acceptable clinical and radiologic outcomes.

Future liver remnant growth after various portal vein embolization regimens: a quantitative comparison

Purpose: To compare the efficacy of right portal vein embolization using ethylene vinyl alcohol (EVOH-PVE) compared to other embolic agents and surgical right portal vein ligation (PVL).Material and methods: Patients with right sided liver malignancies scheduled for extensive surgery and receiving induction of liver hypertrophy via right portal vein embolization/ligature between 2010-2016 were retrospectively evaluated. Treatments included were ethylene vinyl alcohol copolymer (Onyx®, EVOH-PVE), ethiodized oil (Lipiodol^®, Lipiodol/PVA-PVE), polyvinyl alcohol (PVA-PVE) or surgical ligature (PVL). Liver segments S2/3 were used to assess hypertrophy. Primary outcome was future liver remnant growth in ml/day.Results: Forty-one patients were included (EVOH-PVE n = 11; Lipiodol/PVA-PVE n = 10; PVA-PVE n = 8; PVL n = 12), the majority presenting with cholangiocarcinoma and colorectal metastases (n = 11; n = 27). Pre-interventional liver volumes were comparable (p = .095). Liver hypertrophy was successfully induced in all but one patient receiving Lipiodol/PVA-PVE. Liver segment S2/3 growth was largest for EVOH-PVE (5.38 ml/d) followed by PVA-PVE (2.5 ml/d), with significantly higher growth rates than PVL (1.24 ml/d; p < .001; p = .007). No significant difference was evident for Lipiodol/PVA-PVE (1.43 ml/d, p = .809).Conclusions: Portal vein embolization using EVOH demonstrates fastest S2/3 growth rates compared to other embolic agents and PVL, potentially due to its permanent portal vein embolization and induction of hepatic inflammation.

False lumen intervention to promote remodelling and thrombosis-The FLIRT concept in aortic dissection

OBJECTIVE

Thoracic endovascular aortic repair (TEVAR) has changed the management of aortic dissection by induced remodelling. Beyond reconstructing the true lumen, we describe the concept of False Lumen Intervention to promote Remodelling and Thrombosis (FLIRT) in both type A and B aortic dissection.

METHODS

Between 2011 and 2017, 10 patients with aortic dissection (5 type A; 5 type B) underwent FLIRT using a combination of patent foramen ovale (PFO) or atrial septal defect (ASD) occluders, coils and glue. Patients were followed by computed tomography (CT) angiogram prior to, and 6 months following, discharge to evaluate false lumen (FL) thrombosis and aortic remodelling. Outcomes analyzed comprised successful device delivery, completeness of FL thrombosis and aortic remodelling, procedure related complications and mortality.

RESULTS

FLIRT induced aortic remodelling in all cases of proximal dissection, with aortic shrinkage from 63.8 ± 7.5 pre-FLIRT, to 50.2 ± 6.6 mm (P = 0.057) and an increase in true lumen area from 5.8 ± 3.6 to 11.4 ± 2.5 cm2 (P = 0.006). In distal dissection (after previous TEVAR with residual FL flow), FLIRT successfully induced FL thrombosis in 4 of 5 cases at first attempt (1 case required additional coiling of the gutter between left subclavian artery and stent-graft for complete thrombosis). While maximal aortic diameter remained unchanged (55.6 ± 9.1 pre-FLIRT and 54.4 ± 13.7 mm at follow-up), true lumen area increased from 7.8 ± 2.3 pre-procedure, to 10.6 ± 1.5 cm2 at follow-up (P = 0.016), consistent with remodelling.

CONCLUSION

Interventional FL management, using the FLIRT concept, is feasible in selected cases of aortic dissection, promotes FL thrombosis and induces successful remodelling.

Collected Transatlantic Experience From the PERICLES Registry: Use of Chimney Grafts to Treat Post-EVAR Type Ia Endoleaks Shows Good Midterm Results

Purpose: The aim of this retrospective analysis was to evaluate the performance of the chimney (ch) technique in the treatment of type Ia endoleaks after standard endovascular aneurysm repair (EVAR). Methods: Between January 2008 and December 2014, 517 chEVAR procedures were performed in 13 US and European vascular centers (PERICLES registry). Thirty-nine patients (mean age 76.9±7.1 years; 33 men) were treated for persistent type Ia endoleak and had computed tomography angiography or magnetic resonance angiography follow-up at >1 month. Endurant abdominal stent-grafts were used in the 20 cases. Single chimney graft placement was performed in 18 (46%) patients and multiple in 21 (54%). Overall, 70 visceral vessels were targeted for revascularization. Results: Technical success was achieved in 35 (89.7%) cases; 3 persistent type Ia endoleaks and 1 chimney graft occlusion were detected within the first 30 days. Thirty-day mortality was 2.6%. Two other deaths (not aneurysm related) occurred during a mean follow-up of 21.9 months (0.23–71.3). Primary patency of the chimney grafts was 94.3% at 36 months. In a subgroup analysis comparing Endurant to other stent-grafts, no significant differences were observed regarding persistent endoleak [1/20 (5%) vs 2/19 (11%), p=0.6] or reintervention [1/20 (5%) vs 0/19 (0%)]. Conclusion: The present series demonstrates that chEVAR in the treatment of post-EVAR type Ia endoleaks has satisfactory results independent of the abdominal and chimney graft combinations. Midterm results show that chEVAR is an effective method for treating type Ia endoleaks.

Editor's Choice - Occurrence and Classification of Proximal Type I Endoleaks After EndoVascular Aneurysm Sealing Using the Nellix™ Device

OBJECTIVE/BACKGROUND

Proximal type I endoleaks are associated with abdominal aortic aneurysm (AAA) growth and rupture and necessitate repair. The Nellix™ EndoVascular Aneurysm Sealing (EVAS) system is a unique approach to AAA repair, where the appearance and treatment of endoleaks is also different. This study aimed to analyse and categorise proximal endoleaks in an EVAS treated cohort.

METHODS

All patients, treated from February 2013 to December 2015, in 15 experienced EVAS centres, presenting with proximal endoleak were included. Computed tomography scans were analysed by a core laboratory. A consensus meeting was organised to discuss and qualify each case for selection, technical aspects, and possible causes of the endoleak. Endoleaks were classified using a novel classification system for EVAS.

RESULTS

During the study period 1851 patients were treated using EVAS at 15 centres and followed for a median of 494 ± 283 days. Among these, 58 cases (3.1%) developed a proximal endoleak (1.5% early and 1.7% late); of these, 84% of 58 patients were treated outside the original and 96% outside the current, refined, instructions for use. Low stent positioning was the most likely cause in 44.6%, a hostile anatomy in 16.1%, and a combination of both in 33.9%. Treatment, by embolisation or proximal extension, was performed in 47% of cases, with a technical success of 97%.

CONCLUSION

The overall incidence of proximal endoleak after EVAS is 3.1% after a mean follow-up period of 16 months, with 1.5% occurring within 30 days. Their occurrence is related to patient selection and stent positioning. Early detection and classification is crucial to avoid the potential of sac rupture.