Type II Endoleaks After EVAR: A Literature Review of Current Concepts.

Endoleak is the most frequent complication following endovascular aneurysm repair, which is not present in the surgical counterpart. The most frequent type of endoleak corresponds to type II, and its natural history remains poorly understood. Therefore, their treatment continues to be a topic of debate. The vast majority of the studies found in the literature are of a retrospective nature, and there are no prospective studies comparing intervention versus a conservative approach. Future studies should aim to compare not only different approaches to resolve type II endoleak but also when should be the right time to treat them, with the primary purpose of avoiding sac rupture. The objective of this review is to provide the reader with a literature overview about type II endoleaks to help in the decision-making process on this topic.

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.

Incidence of stent graft failure from type IIIB endoleak in contemporary endovascular abdominal aortic aneurysm repair.

BACKGROUND: Type IIIB endoleak from material failure can lead to aneurysmal sac enlargement and latent rupture after endovascular repair of abdominal aortic aneurysm. Long-term durability of the endovascular stent graft is largely unknown, and the complication rate from device failure due to material fatigue may be underappreciated. In addition, even with advancement in imaging techniques, recognition of type IIIB endoleak can be challenging, which can lead to delay in intervention. METHODS: A review of the literature was performed in PubMed and Google Scholar, yielding 23 articles with 46 case reports of type IIIB endoleak from various Food and Drug Administration-approved stent grafts after endovascular repair of infrarenal abdominal aortic aneurysm. RESULTS: The most common location of type IIIB endoleak occurred in the main body (34.8%), followed by the area of the flow divider (32.6%). Sac growth was identified in 63% (29/46) of cases. Diagnosis of the endoleak occurred an average of 54.3 months after the index operation. Endovascular repair was the primary approach for elective repair of type IIIB endoleak (61.3% vs 13.3%). Perioperative mortality was higher in ruptured or symptomatic patients compared with patients undergoing elective repair (33.3% vs 6.5%). CONCLUSIONS: The actual incidence of type IIIB endoleak is still lacking, and the etiology may be multifactorial. Therefore, suspicion of type IIIB endoleak requires appropriate imaging techniques and prompt intervention to reduce the perioperative mortality rate.

Dynamic Volumetric Computed Tomography Angiography Is a Preferred Method for Unclassified Endoleaks by Conventional Computed Tomography Angiography After Endovascular Aortic Repair.

Background The aim of this study was to assess the feasibility and safety of dynamic volumetric computed tomography angiography ( DV - CTA ) for endoleaks detected but not classified by conventional CTA in patients after endovascular aortic repair. Methods and Results From January 2016 to October 2017, 24 patients with endoleaks with aneurysm sac enlargement detected but not classified by conventional CTA were randomly assigned to the conventional CTA group and the DV - CTA group for further evaluation. The amount of contrast agent, radiation dosage, and changes in creatinine during the operation were compared between the 2 groups. Reintervention was performed according to the endoleak classification followed by the 6- and 12-month follow-up. The accuracy of classifying endoleaks by DV - CTA was comparable to that by digital subtraction angiography. Additionally, the total amount of contrast agent and the radiation dosage in the DV - CTA group during the operation were diminished by 14.0% ( P=0.007) and 12.1% ( P=0.004), respectively, compared with those in the conventional CTA group. No contrast-induced nephropathy was observed. All endoleaks were treated instantly after identification. No endoleaks were found in any of the patients during follow-up. Conclusions DV - CTA could replace digital subtraction angiography as an alternative method for the classification of endoleaks that cannot be differentiated by conventional CTA . Additionally, the amount of contrast agent and the total radiation dosage were substantially reduced, which improved safety among operators and patients.

Select type I and type III endoleaks at the completion of fenestrated endovascular aneurysm repair resolve spontaneously.

OBJECTIVE: The Society for Vascular Surgery reporting standards for endovascular aneurysm repair (EVAR) consider the presence of a type I or type III endoleak a technical failure. However, the nature and implications of these endoleaks in fenestrated EVAR (FEVAR) are not well understood. METHODS: We performed a single-center retrospective review of 53 patients who underwent FEVAR with the Zenith Fenestrated AAA Endovascular Graft (Cook Medical, Bloomington, Ind) from 2013 to 2018. We excluded one patient without contrast-enhanced postoperative imaging who was lost to follow-up after discharge. Small, slow, type I and type III endoleaks on completion angiography were routinely observed. We identified patients with completion type I or type III endoleaks by angiography review and characterized endoleak type, location, and rate of resolution on initial postoperative imaging. RESULTS: Fifty-two patients were included; mean age was 75 ± 8 years, 75% were male, and 91% were white. Of 146 visceral vessels (100 renal arteries and 46 superior mesenteric arteries), 145 (99%) were preserved with 103 fenestrations and 43 scallops; 102 (70%) target vessels were stented. After implantation of all device components, 31 patients (60%) had evidence of type I or type III endoleak. Twelve patients (39%) underwent further intervention at the index procedure, and three endoleaks resolved completely. Twenty-eight patients (54%) had a type I or type III endoleak on completion angiography. There were no differences between patients with and without completion endoleaks in baseline demographics, graft design, neck anatomy, or proportion of cases performed within the instructions for use of the device. Perioperative mortality was 1.9%. On initial postoperative imaging, 27 of 28 (96%) endoleaks resolved spontaneously. One small, persistent type IA or type III endoleak was identified on postoperative day 27 and was observed. This endoleak had resolved completely on computed tomography angiography 6 months postoperatively. In patients without a completion endoleak, one type IA endoleak secondary to graft infolding was discovered on postoperative imaging and was successfully treated with placement of endoanchors and Palmaz stent. Median follow-up was 269 days. No additional type I or type III endoleaks were identified in any patient for the duration of follow-up. CONCLUSIONS: Whereas completion type I and type III endoleaks are common after FEVAR with the ZFEN device, nearly all of these endoleaks resolve spontaneously by the initial postoperative imaging. These results suggest that select completion endoleaks after FEVAR with the ZFEN device do not require intervention at the index procedure.

Type 2 endoleaks in endovascular aortic repair: cone beam CT and automatic vessel detection to guide the embolization.

Background Dual-phase cone beam computed tomography (DP-CBCT) and automatic vessel detection (AVD) software are helpful tools for detecting arteries before planned endovascular interventions. Purpose To evaluate the usefulness of DP-CBCT and AVD software in guiding the trans-arterial embolization (TAE) of challenging T2 lumbar endoleaks (T2-L-EL). Material and Methods Ten patients with T2-L-EL were included in this study. The accuracy of DP-CBCT and the AVD software was defined by the ability to detect the endoleak and arterial feeding vessel, respectively. Technical success was defined as the correct positioning of the microcatheter using AVD software and the successful embolization of the endoleak. Clinical success was defined as the absence of recurrent endoleaks during follow-up and the stability of the sac diameter for persistent endoleaks. The total volume of iodinated contrast medium, overall procedure time, mean procedural radiation dose, and mean fluoroscopy time were recorded. Results The EL was detected by DP-CBCT in all patients. The AVD software identified the feeding arterial branch in all cases. In one patient, the nidus of the endoleak was not reached due to the small caliber of the feeding artery, even though the software had clearly identified the vessel route. The mean contrast volume was 109 mL, the mean overall procedural time was 74.3 min. The mean procedural radiation dose was 140.97 Gy cm2, and the mean fluoroscopy time was 29.8 min. Conclusion The use of DP-CBCT and the AVD software is feasible and may facilitate successful embolization in challenging occult T2-L-EL with complex vasculature.

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.

Contrast-Enhanced Ultrasound in the Follow-Up of Endoleaks after Endovascular Aortic Repair (EVAR).

Endovascular aortic repair (EVAR) has become established in the treatment of abdominal aortic aneurysms and shows potential benefits such as a low perioperative morbidity and a short hospitalization duration. The follow-up after EVAR primarily consists of lifelong postinterventional imaging of the aneurysm size in order to detect complications such as endoleaks or stent dislocation. Computed tomography angiography, an imaging modality that uses ionizing radiation and that relies on a contrast medium which is dependent on thyroid and renal function, is widely used for follow-up. Meanwhile, contrast-enhanced ultrasound (CEUS) has been established as a viable, fast and cost-effective imaging alternative for the follow-up and the detection of endoleaks after EVAR with the additional benefit of being a real-time non-ionizing radiation examination and having comparable or even superior diagnostic performance. This review describes the use of CEUS for follow-up after EVAR and describes the most common pathologies.

Embolization for persistent type IA endoleaks after chimney endovascular aneurysm repair with Onyx®.

PURPOSE: The purpose of this study was to determine retrospectively the safety and technical success rate of embolization using ethylene vinyl alcohol copolymer (Onyx®) for persistent type 1A endoleaks after chimney endovascular aneurysm repair (EVAR) for complex aortic aneurysms. MATERIAL AND METHODS: Nine consecutive patients (6 men, 3 women) with a mean age of 78.6 years (range: 62-87 years) presenting with persistent type IA endoleaks after chimney EVAR and an increase of aneurysm size were treated using transarterial embolization with Onyx®. RESULTS: Technical success was obtained in all patients (100%) and no complications were observed. Mean follow-up was 16 months (range: 3-35 months). Primary clinical efficacy was obtained for 8/9 patients (89%) and primary technical efficacy for 6/9 patients (67%). Secondary clinical efficacy was 100%, and secondary technical efficacy was 78%. CONCLUSION: Our results suggest that arterial embolization using Onyx® appears as a feasible and safe endovascular procedure of type IA endoleaks after chimney EVAR, although further validation is now required.

Three-dimensional contrast-enhanced ultrasound improves endoleak detection and classification after endovascular aneurysm repair.

BACKGROUND: Three-dimensional contrast-enhanced ultrasound (3D-CEUS) is a novel technology allowing surgeons to view duplex ultrasound images in three dimensions with ultrasound contrast highlighting blood flow in endoleaks after endovascular aneurysm repair (EVAR). It potentially reduces the need for computed tomography angiography (CTA) and catheter angiography. This study compares 3D-CEUS with both CTA and the final vascular multidisciplinary team (MDT) diagnosis using all available imaging. Interoperator variability for detection of endoleak and the influence of 3D-CEUS on patient management were studied. METHODS: A consecutive 100 patients undergoing CTA for EVAR surveillance were invited to undergo standard CEUS and 3D-CEUS on the same day, with 3D-CEUS reported independently by two blinded vascular scientists. Presence and type of endoleak were compared between CTA, standard CEUS, 3D-CEUS, and the final diagnostic decision made in the vascular MDT meeting. Interoperator reliability of 3D-CEUS was analyzed using the κ statistic. RESULTS: The 100 paired CTA, CEUS, and 3D-CEUS studies were analyzed. Compared with CTA, the sensitivity, specificity, positive predictive value, and negative predictive value of 3D-CEUS to endoleak were 96%, 91%, 90%, and 96%, respectively. Compared with the MDT decision with access to all imaging modalities, the sensitivity, specificity, positive predictive value, and negative predictive value of 3D-CEUS were 96%, 100%, 100%, and 96%. The κ statistic for interoperator agreement was 0.89. CONCLUSIONS: 3D-CEUS was more sensitive and accurate than CTA for endoleak detection and classification after EVAR. 3D-CEUS is now our initial investigation of choice in cases of sac expansion during duplex ultrasound follow-up or if there is diagnostic uncertainty on standard duplex ultrasound or CTA.

Intervention after endovascular aneurysm repair: Endosalvage techniques including perigraft arterial sac embolization and endograft relining.

Endovascular aneurysm repair (EVAR) has revolutionized the treatment of abdominal aortic aneurysm (AAA). However, persistent AAA sac endoleak following EVAR can result in sac diameter increase requiring re-intervention in up to one-third of cases and even result in aneurysm rupture. In this case review, we summarize and detail endovascular re-interventions for each type of endoleak. We also detail specific options including stent-graft relining for indeterminate, Type III, and Type IV endoleaks and perigraft arterial sac embolization to induce thrombosis and resolve acute Type I, II, or III endoleaks. Endograft relining involves placement of a new stent-graft-elevating the bifurcation and extending the repair from renal artery to hypogastric arteries; perigraft arterial sac embolization involves placement of a catheter into the excluded sac from common femoral artery access, characterization of the inflow and outflow of the endoleak, and inducing cessation of the blood flow into the sac by the administration of thrombogenic material. Endoleaks range from low-pressure endoleaks, which can be safely monitored in a surveillance program to high-pressure endoleaks, which mandate intervention when associated with AAA sac diameter increase to protect from rupture. The evaluation of new devices and techniques to treat endoleak after EVAR remains an important issue in patient care after EVAR.

Resultados em longo prazo de embolização de endoleaks tipo II / Long-term outcomes of embolization of type II endoleaks

CONTEXTO: Endoleaks tipo II são frequentes após o reparo endovascular de aneurismas de aorta. OBJETIVO: O objetivo deste estudo foi comparar o sucesso da embolização de endoleaks tipo II utilizando diferentes técnicas e materiais. MÉTODOS: Entre 2003 e 2015, 31 pacientes foram submetidos a embolização de endoleak tipo II, totalizando 41 procedimentos. Esses procedimentos foram conduzidos por acesso translombar, acesso femoral ou uma combinação de ambos, utilizando Onyx®18, Onyx®34, coils, plugue vascular Amplatzer® e trombina como material emboligênico. Sucesso foi definido como ausência de reintervenção. O teste de qui-quadrado e o teste exato de Fisher foram utilizados para a análise estatística. RESULTADOS: O tempo médio entre a correção do aneurisma de aorta e a embolização foi de 14 meses. Quinze (36%) das intervenções utilizaram Onyx®18; sete (17%) utilizaram coils e Onyx®34; seis (14%) utilizaram Onyx®34; quatro (10%) utilizaram coils e Onyx®18; quatro (10%) usaram Onyx®18 e Onyx®34; e três (7%) usaram coils e trombina; um (2%) usou coils e um (2%) usou Amplatzer®. Onze pacientes (35%) necessitaram de reintervenção. A taxa de sucesso foi de 71,43% (10) para os pacientes com as artérias lombares como fonte do endoleak, 80% (8) quando a fonte era a artéria mesentérica inferior e 40% (2) quando havia combinação de ambas (p & 0,05). Não houve diferença estatisticamente significativa com relação ao tipo de embolização, material emboligênico e tipo de reparo da aorta para a correção do aneurisma. CONCLUSÕES: A terapia endovascular de endoleaks tipo II é um desafio, sendo necessária reintervenção em até 36% dos casos. A taxa de sucesso é menor quando o endoleak é nutrido pela combinação das artérias lombares e da artéria mesentérica inferior.

BACKGROUND: Type II endoleaks are common after endovascular aortic aneurysm repair. The purpose of this study was to assess the long-term outcomes of embolization of type II endoleaks using different techniques and materials. METHODS: Between 2003 and 2015, 31 patients underwent embolization of type II endoleaks, in a total of 41 procedures. Patients underwent transarterial or translumbar embolization using Onyx®18, Onyx®34, coils, Amplatzer® plug and/or thrombin. Embolization success was defined as no endoleak reintervention. The chi-square test and Fisher exact test were used for statistical analysis. RESULTS: Median embolization time after aortic aneurysm repair was 14 months. Fifteen (36%) embolization interventions were performed using Onyx®18; seven (17%) with coils and Onyx®34; six (14%) with Onyx®34; four (10%) with coils and Onyx® 18; four with Onyx®18 and Onyx®34; three (7%) with coils and thrombin; one (2%) with coils; and one (2%) with an Amplatzer® device. Eleven patients (35%) required reintervention. The embolization success rate was 71.43% (10) for patients with lumbar arteries as the source of the endoleak, 80% (8) for the inferior mesenteric artery and 40% (2) when both inferior mesenteric artery and lumbar arteries were the culprit vessels (p & 0.05). There was no statistically significant difference with regards to type of embolization, embolic material or type of previous aortic repair. CONCLUSIONS: Endovascular treatment of type II endoleaks is challenging and reintervention is needed in up to 36% of patients. Endoleaks supplied by both the inferior mesenteric artery and the lumbar arteries have a lower rate of success.

Unusual approach for the treatment of a type II endoleak. / Abordaje inusual en el tratamiento de las endofugas aórticas tipo II.

This case presentation is about an 88 years-old male patient with previous endovascular aortic aneurysm repairment history and aortic endoleak type II (EL2). The direct lumbar artery catheterization was considered an alternative to solve EL2, associated with aortic endovascular prosthesis and due to an incomplete sealing or exclusion of the aneurysmal sac or a vascular segment demonstrated by imaging studies, when other treatment alternative failed (transarterial embolization) to control the aneurysm growing. Performing translumbar approach was decided by puncturing the artery lumbar (L4) left, previously the lumbar arteries (L4) were evaluated in the abdominal CT arterial phase to guide a puncture/access under flouroscopy control. Diagnostic angiogram clearly demonstrated the median sacral and right lumbar arteries inflow into the aneurysm sac. Transcatheter embolization with fibered platinum microcoils was performed of the median sacral artery and lumbar left and right arteries (L4), showing satisfactory endoleak devascularization.

Transcatheter Embolization of Type IA Endoleak after Nellix Endovascular Aortic Aneurysm Sealing with N-Butyl Cyanoacrylate: Technique in Three Patients.

The successful transcatheter treatment of a type IA endoleak after endovascular aortic aneurysm sealing with the Nellix EndoVascular Aneurysm Sealing system (Endologix Inc, Irvine, California) using proximal covered stent extension and transarterial N-butyl cyanoacrylate sac embolization is described. Three patients were treated using the same technique with a mean interval between the index procedure and reintervention of 9.3 months (range, 3-15 mo). No complications or endoleaks were seen on follow-up imaging. The mean follow-up time after reintervention was 10.3 months (range, 7-13 mo).

Systemic Inflammatory Disease and Its Association With Type II Endoleak and Late Interventions After Endovascular Aneurysm Repair.

IMPORTANCE: Abdominal aortic aneurysms are associated with chronic inflammation within the aortic wall, and previous studies have suggested that chronic inflammation may be a consequence of a dysregulated and persistent autoimmune response. Persistent aortic remodeling after aneurysm repair could place the patient at risk for endoleak or sac rupture. OBJECTIVE: To determine whether patients with systemic inflammatory disease and large aneurysms have persistent aortic remodeling after endovascular aneurysm repair (EVAR). DESIGN, SETTING, AND PARTICIPANTS: The records of all patients who underwent EVAR between July 2002 and June 2011 at the Veterans Affairs Connecticut Healthcare System were included in this retrospective review. Patients were considered to have a systemic inflammatory disease when confirmed by a referring specialist. Post-EVAR surveillance was performed by yearly imaging. INTERVENTION: Endovascular aneurysm repair. MAIN OUTCOMES AND MEASURES: Significant endoleak, defined as endoleak and sac diameter increase of 0.5 cm or greater. RESULTS: A total of 51 of 79 patients (65%) had a systemic inflammatory disease. These patients had similar comorbid conditions compared with patients without inflammation but significantly greater numbers of major postoperative complications after EVAR (23.5% vs 3.6%; P = .02) and overall postoperative complications after EVAR (27.5% vs 7.1%; P = .03). Patients with a history of systemic inflammatory disease developed more endoleaks (45.1% vs 17.9%; P = .02) and late sac expansion (51.0% vs 21.4%; P = .01) and required more interventions (21.6% vs 3.6%; P = .03) during long-term follow-up. Systemic inflammatory disease was significantly associated with significant endoleak (odds ratio, 5.18; 95% CI, 1.56-17.16; P = .007). CONCLUSIONS AND RELEVANCE: Patients with systemic inflammatory disease are at high risk for postoperative complications, type II endoleak, sac expansion, and additional interventions after EVAR. Additional strategies for improving the efficacy of EVAR in these patients may be warranted.

CT features of early type II endoleaks after endovascular repair of abdominal aortic aneurysms help predict aneurysm sac enlargement.

PURPOSE: To determine computed tomographic (CT) features of early type II endoleaks associated with aneurysm sac enlargement after endovascular aortic aneurysm repair (EVAR) of abdominal aortic aneurysm. MATERIALS AND METHODS: Institutional review board approval was not required for this retrospective study. The authors reviewed imaging and clinical data from 56 patients (seven women, 49 men; mean age ± standard deviation, 71 years ± 7.9; age range, 52-85 years) with early type II endoleak who had undergone EVAR between December 2002 and December 2011 and who had been followed up with imaging and clinical evaluation for at least 6 months. The number and diameter of all feeding and/or draining arteries were measured, and endoleaks were classified according to their sources into simple inferior mesenteric artery (IMA), simple lumbar artery (LA), complex LA, and complex IMA-LA type II endoleaks. Volume and attenuation of the nidus were measured. Aneurysm enlargement was defined as an increase in the aneurysm volume of more than 5% during follow-up. Simple and multivariate logistic regression analyses were performed to identify independent clinical and imaging variables associated with aneurysm enlargement. RESULTS: Twenty-three of the 56 patients (41%) showed aneurysm sac enlargement during follow-up (mean follow-up, 3.0 years ± 2.0). With the multivariate model, the variables that showed the strongest indicators for aneurysm sac enlargement were complex IMA-LA type II endoleak (odds ratio [OR] = 10.29, P = .004) and the diameter of the largest feeding and/or draining artery (OR = 4.55, P = .013). Patients without complex IMA-LA type II endoleak in whom the largest feeding and/or draining artery was larger than 3.8 mm and patients with a complex IMA-LA type II endoleak in whom the largest feeding and/or draining artery was larger than 2.2 mm were at high risk for aneurysm sac enlargement. CONCLUSION: The strongest indicators for aneurysm sac enlargement are complex IMA-LA type II endoleak and the diameter of the largest feeding and/or draining artery.