Midterm Outcomes After Treatment of Type II Endoleaks Associated With Aneurysm Sac Expansion

Effectiveness of Intra-operative Contrast-Enhanced Ultrasound Assessment to Optimize Type II Endoleak Embolization

PURPOSE

To analyze the effectiveness of type II endoleaks (T2E) embolization using intra-operative contrast-enhanced ultrasound (CEUS).

METHODS

Consecutive patients treated for T2E underwent a standardized protocol with trans-arterial or trans-lumbar access, large volume embolization, onlay fusion, and intra-operative CEUS. Technical success was defined by exclusion of endoleak by CEUS.

RESULTS

Twenty-six patients (mean age 81 ± 11 years old; 89% male) were treated. The mean aneurysm sac enlargement was 11 ± 8 mm from T2E diagnosis. Embolization was performed using Onyx® 18 in all patients with adjunctive coils in 13 patients (50%). After the first embolization, CEUS documented residual T2E in 13 patients (50%). Ten patients (38%) had additional embolization, which successfully eradicated the T2E in seven of them. Technical success was 50% after the first embolization attempt and 77% after additional attempts guided by CEUS (P = 0.080). There was no mortality. Median imaging follow-up was 22 months. Among the 20 patients with no residual T2E on completion CEUS, 16 (80%) had sac stabilization and none required additional interventions for T2E. Of the six patients with residual T2Es on CEUS, three had sac stabilization (50%) and one required additional reintervention for T2E. There was one late aortic rupture at 56 months.

CONCLUSION

One in two patients treated by T2E embolization had residual endoleak on intra-operative CEUS after a first embolization attempt, decreasing to one in four patients after multiple attempts. A negative completion CEUS following embolization was associated with higher rates of sac stabilization and no need for additional T2E embolization.

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.

Outcomes of Endurant II Stent Graft According to Anatomic Severity Grade Score

OBJECTIVES

This study's objective was to evaluate Endurant II (Medtronic Inc, Minneapolis, Minnesota) stent graft's early and midterm outcomes and compare the results according to the anatomic severity grade (ASG) scores.

METHODS

This was a retrospective study of patients treated with the Endurant II stent graft between January 2013 and May 2021. The patients were divided into 2 independent groups, including those with a low ASG score (score <14) and a high ASG score (score >14).

RESULTS

A total of 165 consecutive patients (89% males, age 74±8 years) were included. There were 110 (67%) patients in the low-score group and 55 (33%) patients in the high-score group. Technical success was achieved in all cases. Primary clinical success at 30 days was 100% and at 1 year was 96%. Median operative time was longer in the high-score group with no statistical significance (133 vs 120 minutes, p=0.116). The median dose area product of low-score patients (50.9 Gy·cm2; IQR 22.4-75.5 Gy·cm2) was significantly lower than high-score patients (85.0 Gy·cm2; IQR 46.5-127.9 Gy·cm2) with p=0.025. Median fluoroscopic time was lower in low-score patients (17 minutes; IQR 13-24 minutes) compared with high-score patients (19 minutes; IQR 16-23 minutes) without a significant difference at p=0.148. At a midterm follow-up of 32 months (range 2-63 months), combined complications (29% vs 8%, p<0.001) and implant-related complications (13% vs 4%, p=0.043) were higher in the high-score group. Systemic complications at 30 days were higher in the high-score group without a statistically significant difference (15% vs 11%, p=0.500). The Kaplan-Meier estimate of freedom from reintervention was significantly higher in the low-risk group at 1 (97% vs 90%), 2 (96% vs 88%), and 3 years (96% vs 85%) with (p=0.035). The cumulative survival rate was significantly higher in the low-score group than high-score group (p=0.001) at 1 (99% vs 87%), 2 (98% vs 85%), and 3 years (96% vs 82%).

CONCLUSIONS

Endurant II endovascular aneurysm repair seems to be safe in both low-score and high-score patients. However, patients in the high-score group showed more implant-related complications and midterm mortalities than those in the low-score group.

Role of Aggressive Aneurysm Sac Embolization Before Endovascular Abdominal Aneurysm Repair in Preventing Type II Endoleak and Sac Expansion

Background

This study aimed to evaluate the effect of aggressive embolization of side branches arising from the aneurysmal sac before endovascular aneurysm repair.

Methods

This retrospective study included 95 patients who underwent endovascular infrarenal abdominal aortic aneurysm repair at Tottori University Hospital between October 2016 and January 2021. Of these, 54 underwent standard endovascular aneurysm repair (conventional group), and 41 underwent coiling of the inferior mesenteric and lumbar arteries before undergoing endovascular aneurysm repair (embolization group). The occurrence of type II endoleak, change in aneurysmal sac diameter, and reintervention rate due to type II endoleak during follow-up were evaluated.

Results

Compared to the conventional group, the embolization group had a significantly lower incidence of type II endoleak, more frequent aneurysmal sac shrinkage, and lower aneurysmal sac growth related to type II endoleak.

Conclusion

Our results demonstrated the effectiveness of aggressive aneurysmal sac embolization before endovascular aneurysm repair to prevent type II endoleak and the consequent long-term aneurysmal sac enlargement.

Evolution of open aneurysmorrhaphy for management of sac expansion after endovascular repair of abdominal aortic aneurysms

OBJECTIVE

We evaluated the perioperative and mid-term clinical outcomes of open aneurysmorrhaphy (OA) for the treatment of sac expansion after endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms.

METHODS

OA involves sac exposure without dissection of the proximal or distal neck, sacotomy and ligation of back-bleeding vessels, preservation of the prior stent graft, and tight closure of the sac around the stent graft. We performed a retrospective review of all patients who had undergone OA for nonruptured sac expansion after standard EVAR at our institution between January 2015 and June 2021. The primary end points were 30-day mortality and aneurysm-related death. The secondary end points were postoperative complications, overall survival, freedom from reintervention, and sac regrowth rate.

RESULTS

A total of 28 patients had undergone OA. Their mean age was 76.9 ± 6.7 years. The median sac diameter at OA was 79 mm (interquartile range [IQR], 76-92 mm). The median duration from the index EVAR to OA was 82 months (IQR, 72-104 months). Preoperative computed tomography angiography confirmed a type II endoleak (EL) in 20 patients, 1 of whom had had a coexisting type Ia EL; a type IIIb EL was identified in 1 patient. Concomitant endovascular procedures had been performed in six patients to treat a type I or III EL or reinforce the proximal and distal seals. The OA technique has been modified since 2017, with the addition of more aggressive dissection of the sac and complete removal of the mural thrombus to further decrease the sac diameter. Postoperative complications occurred in two patients and included abdominal lymphorrhea and failed hemostasis of the common femoral artery requiring surgical repair in one patient each. The 30-day mortality was 0%. During the median follow-up of 36 months (IQR, 14-51 months), the overall survival was 92.7% and 86.9% at 12 and 36 months, respectively, without any aneurysm-related death. In the late (2017-2021) treatment group, the median sac diameter immediately after OA was smaller than that in the early (2015-2016) treatment group (early group: median, 50 mm; IQR, 39-57 mm; vs later group: median, 41 mm; IQR, 32-47 mm; P = .083). Furthermore, in the late group, the sac regrowth rate was lower (early group: median, 0.36 mm/mo; IQR, 0.23-0.83 mm/mo; vs late group: median, 0 mm/mo; IQR, 0-0.11 mm/mo; P = .0075) and the freedom from reintervention rate was higher (late group: 94.7% at both 12 and 36 months, respectively; early group: 71.4% and 53.6% at 12 and 36 months, respectively; log-rank P = .070).

CONCLUSIONS

Our results have shown that OA for the management of post-EVAR sac expansion is feasible with acceptable mid-term outcomes. Aggressive dissection and tight plication of the sac might be imperative for better mid-term outcomes after OA.

Evaluation Of The Effectiveness Of Endovascular Treatment Of Type 2 Endoleaks

INTRODUCTION

Endovascular abdominal aortic aneurysm repair (EVAR) is a safe and minimally invasive alternative to open surgical repair for infra renal aortic aneuvrysm. EVAR requires lifelong post-procedural surveillance. Endoleaks represent the main complication. Type II endoleaks (EL2) are the most frequent and tend to be indolent. Most practitioners do not treat in EL2 as long as they are associated with stable aneurysm diameter. European guidelines recommend treatment in case of aneurysm growth. Several techniques can be offered, such as transarterial embolization and translumbar embolization. This study reports the experience and results of a single center for EL2 endovascular treatment. The aim of this study was to determine more precisely the efficacity of embolization for type 2 endoleaks treatment.

MATERIAL AND METHODS

A single center cohort of patients treated for EL2 with endovascular technique between 1998 and 2018 was formed to perform a descriptive analysis. Preoperative sizing, risk factors of endoleaks and intraoperative data were collected. CT scans were regularly performed after EVAR to detect endoleak recurrence. Clinical recurrence was defined as the persistence of aneurysm sac growth and radiological recurrence was defined as the occurrence of EL2 on a post-embolization CT scan. Data related to reintervention, overall mortality and aneurysm related mortality were also collected. Kaplan Meier survival analyses were used to determine the rates of reoperation-free survival and recurrence-free survival.

RESULTS

Six hundred seven patients underwent an endovascular treatment for abdominal aorta aneurysm between 1998 and 2018. One hundred forty-five type 2 endoleaks occurred during this period. Nineteen patients (median age 76 years), underwent endovascular treatment for EL2, with immediate success on 15 patients (8 transarterial embolization, 8 direct sac puncture and 3 combined procedures). During follow-up, 5 patients required a new translumbar embolization and 6 required an open surgery for recurrence of the EL2. Six patients died, 2 of them of causes related to the aneurysm. At 59,6 months median follow-up, 53% of the patients presented a radiologic recurrence, with a sac growth of more than 5 mm since last procedure in 4 patients (24%).

CONCLUSION

Long term clinical recurrence of type 2 endoleaks treated by endovascular procedures appear to be frequent in our experience, leading to several deaths and requiring open surgical treatment.

Efficacy of contrast-enhanced ultrasound in detection of type II endoleak after abdominal aortic aneurysm surgery: A prospective cohort study

PURPOSE

This study aimed to evaluate the efficacy of conventional contrast-enhanced ultrasound (CEUS) in detection of type II endoleak after endovascular abdominal aortic aneurysm repair (EVAR).

METHODS

From January 2015 to April 2018, 205 patients underwent EVAR were included. CEUS and computed tomography angiography (CTA) were performed at 1-month follow-up postoperatively to detect type II endoleak. CEUS was performed at 3- and 6-month follow-up to evaluate the development of type II endoleak. The diameter extension of type II endoleak increased greater than 5 mm was defined as enlarge group, and that increased less than 5 mm was defined as stable group. The difference of arrival time (AT) of contrast agent, maximum cross-sectional area (MCSA) of contrast agent and the blood flow velocity (BFV) of the abnormal blood around the stent graft were compared.

RESULTS

At 1-month after EVAR, 65 cases of endoleak were detected by CEUS, including 25 cases of type I, 30 cases of type II endoleak and 10 cases of type III endoleak. Among them, 50 cases were also detected by CTA. The diameter extension of 12 cases of type II endoleak increased greater than 5 mm, and that of eight cases increased less than 5 mm. The average AT of the enlarge group was significantly shorter than that of the stable group, while the MCSA of contrast agent and the BFV were significantly higher than that of the stable group (p < 0.05).

CONCLUSION

CEUS has predictive value for the natural outcome of type II endoleak.

A systematic review of the current status of interventions for type II endoleak after EVAR for abdominal aortic aneurysms

OBJECTIVE

To study the mid- and long-term outcomes of type II endoleak treatment after EVAR and the technical aspects of different techniques to exclude endoleaks which different embolic agents.

METHODS

A systematic review was performed using the approach recommended by the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for meta-analyses of interventional studies. The comprehensive search was conducted using the following database: MEDLINE, EMBASE, and the Cochrane Library. Patient characteristic, intervention approaches, embolic agents, and results at mid and long term follow up were studied.

RESULTS

A total of 6 studies corresponding to a total of 141 patients fulfilled the inclusion criteria with a mean age of 73-78.6 years and a mean duration of follow up varying from 25 to 42 months. There were different techniques for embolization used (translumbar, transarterial, and transcaval approach) with various types of embolic agents. In all studies, the indication for embolization of the type II endoleaks was sac enlargement of more than 5 mm. A wide range of technical success rate was reported regardless of the intervention strategy being used (17,6%-100%). The overall technical success rate of all studies was 62%.

CONCLUSION

This systematic review shows that there is a wide variety of techniques to exclude a persistent type II endoleak. Different kinds of embolic agents have be used. Due to a lack of peer reviewed data on longterm follow-up, it was not possible to come to recommendations what treatment would be the best for a durable exclusion of a persistent type II endoleak after an initially successful EVAR. There remains an urgent need for proper executed studies, either randomized or with close observation in relation to longer follow-up.

Laparoscopic lumbar artery ligation of type II endoleaks following endovascular aneurysm repair: A case report

INTRODUCTION

Although the clinical significance of type II endoleaks remain controversial, management strategies continue to expand. The laparoscopic approach is a minimally invasive method for persistent type II endoleak repair after endovascular aneurysm repair.

PATIENT CONCERNS

A 70 - year - old male patient with a history of endovascular aneurysm repair with left internal iliac artery embolization presented with persistent type II endoleak from the lumbar arteries 2 years ago. The aneurysm sac size had increased more than 10 mm during follow up period.

DIAGNOSIS

Persistent type II endoleak after endovascular aneurysm repair.

INTERVENTIONS

Transarterial embolization was attempted and failed. A minimally invasive laparoscopic lumbar artery ligation was then utilized.

OUTCOMES

The patient was discharged without any complications after surgery. Follow-up computed tomography angiography has shown the complete disappearance of the type II endoleaks.

CONCLUSIONS

Laparoscopic lumbar artery ligation may be a safe and effective alternative treatment for type II endoleaks, especially in high resource settings.

Successful repair of an arteriovesical fistula as a complication after coil embolization for right hypogastric artery aneurysm

An 84-year-old man has a history of a right hypogastric artery aneurysm that was excluded with endograft several years ago. His course was complicated by a type II endoleak with an enlarging aneurysm that required multiple attempts of coil embolization. Several years later, he presented with gross hematuria and was found to have embolization coils extruding into his bladder and an arteriovesical fistula. As seen in this case, endovascular intervention for a type II endoleak is not benign. We describe a novel complication of an arteriovesical fistula that necessitated a difficult repair and ultimate revascularization.

Surgical treatment patterns and clinical outcomes of patients treated for expanding aneurysm sacs with type II endoleaks after endovascular aneurysm repair

OBJECTIVE

Persistent type II endoleaks (T2ELs) after endovascular aneurysm repair (EVAR) with sac growth have been associated with adverse events, including rupture. Whereas intervention in the presence of aneurysm growth has become an accepted treatment paradigm for T2ELs, the efficacy and clinical success of such interventions remain unclear. Therefore, we examined the treatment patterns and clinical outcomes of patients undergoing T2EL interventions after EVAR.

METHODS

We performed a retrospective review of all patients treated for expanding aneurysm sacs with T2ELs after EVAR at an academic medical center between 2006 and 2017. The primary outcomes assessed were need for repeated intervention; intervention types; and achievement of clinical success, defined as stable aneurysm sac size on computed tomography angiography after treatment.

RESULTS

Fifty-six patients underwent 119 interventions, of which 107 (90%) were technically successful. The median time from EVAR to index T2EL procedure was 37 months (interquartile range, 17-56 months), and the median follow-up time from first T2EL procedure was 27 months (interquartile range, 10-51 months). The most common index procedure was transarterial lumbar embolization (64%), followed by transarterial inferior mesenteric artery (20%), transcaval (14%), and translumbar embolization (1.8%). Thirty-three (59%) patients required further procedures for persistent aneurysm sac expansion. For subsequent T2EL interventions, the most common endovascular procedure was transarterial lumbar embolization (21%), followed by transcaval (21%), translumbar (11%), and transarterial inferior mesenteric artery embolization (8.6%). Twelve patients (21%) were found to have loss of proximal or distal seal on subsequent imaging and required graft extensions to stabilize aneurysm sac size. Ten patients (18%) ultimately underwent graft explantation or sacotomy with oversewing of the endoleak source. Freedom from any endoleak-related reintervention was 57% at 1 year and 36% at 3 years. Freedom from open treatment was 93% at 1 year and 82% at 3 years. Of the 44 patients with ≥6-month follow-up, 39 (89%) achieved clinical success. However, only 11 patients (25%) achieved clinical success without any further reintervention, and 29 patients (66%) achieved clinical success without open treatment.

CONCLUSIONS

Despite high technical success, endoleak recurrence after T2EL treatment is common, and multiple interventions are often needed to stabilize aneurysm sac size in patients diagnosed with T2EL-associated sac growth. Notably, one in five patients treated for T2ELs was discovered, on further evaluation, to have proximal or distal seal zone loss that necessitated repair to achieve sac stability. Thus, thorough assessment of all endoleak types should be performed in patients with T2ELs associated with sac growth before T2EL treatment to ensure appropriate care and to minimize ineffective interventions.

The association between perioperative embolization of hypogastric arteries and type II endoleaks after endovascular aortic aneurysm repair

OBJECTIVE

Type II endoleaks (T2ELs) are the most common type of endoleak after endovascular aneurysm repair (EVAR). The iliolumbar artery arising from the hypogastric artery is often a major source of T2ELs, and transarterial embolization of the iliolumbar artery through the hypogastric artery is sometimes performed to interrupt sac expansion during follow-up. Considering the equivocal results of an association between hypogastric embolization and T2ELs in previous studies, this topic has re-emerged after the advent of iliac branch devices. This study reviewed our series to clarify whether hypogastric embolization is associated with T2ELs at 12 months after EVAR.

METHODS

Patients who underwent elective EVAR between June 2007 and May 2017 at our institution were retrospectively reviewed. Patients with postoperative computed tomography angiography (CTA) at 12 months were included. Patients in whom CTA revealed type I or type III endoleaks during follow-up, who required reinterventions before 12 months, and who had solitary iliac aneurysms were excluded. The primary outcome was the incidence of T2ELs at 12 months after EVAR. The associations of patients' characteristics, anatomic factors, hypogastric embolization, and type of endograft with the primary outcome were analyzed.

RESULTS

In total, 375 patients were enrolled. During the median follow-up of 59.5 months (interquartile range, 19-126 months), 40 patients died, and 50 reinterventions were performed. In 108 patients (28.8%), either hypogastric artery was embolized to extend distal landings to the external iliac artery. Bilateral and unilateral embolization was performed in nine and 99 patients, respectively. In total, 153 patients (40.8%) had T2ELs found by CTA at 12 months. In the univariate analysis, the status of hypogastric artery occlusion or embolization was not significantly different between patients with and without T2ELs. However, there were not enough patients to detect a 10% difference in T2ELs with >80% statistical power. In the multivariate analysis, significant associations with T2EL were observed for female sex (P = .049), patent inferior mesenteric artery (P = .006), and presence of five or more patent lumbar arteries (P < .001) but not for hypogastric embolization. In addition, compared with the Zenith (Cook Medical, Bloomington, Ind) endograft, the Excluder (W. L. Gore & Associates, Flagstaff, Ariz) endograft was significantly related to T2EL (P = .001).

CONCLUSIONS

No significant association between hypogastric embolization and T2EL was demonstrated in this retrospective study, which lacked adequate statistical power.

Duplex scanning as an alternative to computer tomography with contrast enhancement for the control of complications after endovascular aneurysm repair

EVAR (endovascular aneurism repair) is the preferred method for the surgical treatment of ananeurysm. The advantage of this type of surgical intervention is that a smaller number of postoperative complications will occur. The main diagnostic tasks for patients after EVAR are to determine the size of the aneurysmal sac, detection of an endoleak, detection of the endoprosthesis migration and the deformation of the stent graft itself. Conclusion: early detection of complications in the postoperative period remains the main problem for monitoring patients after EVAR. Duplex scanning is a safe, non-invasive and effective method of measuring the size of an aneurysmal sac and detecting possible complications after EVAR.

Effectiveness of Embolization of Inferior Mesenteric Artery to Prevent Type II Endoleak Following Endovascular Aneurysm Repair: A Review of the Literature

Type II endoleak is a common complication that develops after endovascular aneurysm repair. Patients with type II endoleak, which has persisted for 6 months, have a significantly higher rate of aneurysmal sac enlargement, reintervention, and rupture. To date, several studies have examined the effectiveness of preoperative embolization of branch vessels for the prevention of type II endoleak. Particularly, the embolization of the large inferior mesenteric artery (IMA) seems to be a precise, safe, and effective method. IMA is a significant risk factor for type II endoleak. However, there is currently no strong evidence to prove which patients would benefit from preventive IMA embolization. In addition, considering the incidence of type II endoleak and the adverse event rate, routine embolization seems to be unreliable and time-consuming. Moreover, previous reports of preoperative IMA embolization were retrospective. Thus, prospective and randomized studies are necessary so that the usefulness of IMA embolization can be proved and the potential benefits can be assessed. To establish preventive IMA embolization as one of the effective therapeutic strategies to prevent type II endoleak and to maximize its therapeutic effect, we should provide a wide range of therapeutic strategies to suit the state of the patient.

Editor's Choice - Systematic Review and Meta-Analysis of the Outcome of Treatment for Type II Endoleak Following Endovascular Aneurysm Repair

OBJECTIVES

The efficacy and need for secondary interventions for type II endoleaks following endovascular abdominal aortic aneurysm repair (EVAR) remain controversial. This systematic review aimed at investigating the clinical outcomes of different type II endoleak treatments in patients with a persistent type II endoleak after EVAR.

DATA SOURCES

Embase, Medline via Ovid, Web of Science Core Collection, the Cochrane CENTRAL, and Google Scholar.

REVIEW METHODS

This systematic review was performed in accordance with the PRISMA Statement. Outcomes of interest were technical and clinical success, change in sac diameter, complications, need for additional interventions, abdominal aortic aneurysm (AAA) rupture, and (AAA related) mortality. Meta-analyses were performed with random effects models.

RESULTS

A total of 59 studies were included, with a cumulative cohort of 1073 patients with persistent type II endoleak. Peri-operative complications following treatment of type II endoleaks occurred in 3.8% of patients (95% CI 2.7-5.2%), and AAA related mortality was 1.8% (95% CI 1.1-2.7%). Overall technical success was 87.9% (95% CI 83.1-92.1%), while clinical success was 68.4% (95% CI 61.2-75.1%). Among studies detailing sac dynamics, decrease or stable sac, with or without resolution, was achieved in 78.4% (95% CI 70.2-85.6%). Changes in sac diameter following type II endoleak treatment were documented in 157 patients to at least 24 months. Within this group an actual decrease in sac diameter was reported in only 27 of 40 patients.

CONCLUSION

There is little evidence supporting the efficacy of secondary intervention for type II endoleaks after EVAR. Although generally safe, the lack of evidence supporting the efficacy of type II endoleak treatment leads to difficulty in assessing its merits.

Selective Inferior Mesenteric Artery Embolization during Endovascular Abdominal Aortic Aneurysm Repair to Prevent Type II Endoleak

PURPOSE

The purpose of this study was to evaluate the efficacy of simultaneous IMA (s-IMA) embolization during the endovascular abdominal aortic aneurysm repair (EVAR).

MATERIALS AND METHOD

From July 2007 to January 2011, 189 patients in the no embolization (NE) group underwent EVAR without the indication for s-IMA embolization. Since February 2011 to April 2014, 143 patients have undergone EVAR. Among these patients, 26 patients underwent s-IMA embolism under a predefined indication and constituted the simultaneous embolization (SE) group. The indications for s-IMA embolization were defined by preoperative computed tomography (CT) findings, as follows: (1) the diameter was greater than 2.5 mm and (2) no stenosis due to thrombus or calcification at its orifice.

RESULTS

The incidence of a type II endoleak from the IMA was 3.4% (5/143) in the SE group patients and 13.2% (25/189) in the NE group patients (p = 0.013), and the incidence of a type II endoleak from all branches (i.e., IMA, lumbar, medial sacral arteries) was 15.4% (22/143) in the SE group patients and 32.3% (61/189) in the NE group patients (p = 0.0003). During the follow-up period (range, 6-72 months; mean: 28 months), the reintervention rate for a type II endoleak from the IMA and/or other branches was 9.5% (18/189) in the NE group and 0.6% (1/143) in the SE group (p = 0.0001).

CONCLUSION

In selected patients, performing an s-IMA embolization, based on CT findings, decreased the incidence of a type II endoleak and reintervention from the IMA and from all branches.

An Institution-Wide Algorithm for Treatment of Type II Endoleak Following Endovascular Aneurysm Repair (EVAR)

Objectives:

Multiple endovascular techniques have been described for the treatment of persistent type II endoleaks (pT2ELs) causing aneurysm sac growth following endovascular aneurysm repair (EVAR). In the event of a failed endovascular procedure and a pT2EL, a consensus regarding further treatment is lacking, and the literature suggests repeated endovascular attempts are rarely successful. Herein, we propose an algorithm for definitive management of pT2ELs with persistent sac growth following EVAR.

Methods:

A retrospective review of 29 patients who underwent treatment of persistent sac growth in the setting of pT2ELs was performed. Intervention methods were determined at the discretion of the operating surgeon. Aneurysmal sac enlargement was defined as a diameter increase > 5 mm, and persistent endoleak was defined as lasting greater than 6 months.

Results:

From 2000 to 2015, 917 EVAR procedures were performed at our institution. Isolated pT2ELs with sac enlargement were identified in 29 patients. Twenty-five patients underwent direct translumbar sac puncture and coiling and/or Onyx (Onyx, Plymouth, Minnesota) embolization of the culprit vessels. Thirteen (52%) of 25 patients had pT2EL after first endovascular intervention, and 10 (40%) of 25 patients failed 2 endovascular treatments. Of those 10, 7 displayed persistent aneurysmal sac growth and underwent a third embolization procedure. Type II endoleaks persisted in 6 patients; 3 patients were subsequently treated with laparotomy, ligation of lumbar vessels, sac exploration, and sac plication around the endograft. Technical success for this technique was 100%. During a mean follow-up of 38.4 months, no recurrent T2ELs, stent graft migration, and/or disjunction were observed.

Conclusions:

We propose a new algorithm for the management of pT2ELs. If 2 endovascular procedures fail to control of the endoleak, repeat endovascular attempts are not recommended. Endovascular failure should be followed by laparotomy with surgical ligation of culprit feeding vessels followed by sac exploration and plication of the sac, and endoaneurysmorrhaphy.

Endovascular and open surgical treatment of complications after endovascular aortic aneurysm repair: A single-center experience

While endovascular aortic aneurysm repair (EVAR) has proven to be a safer alternative to open surgical repair for infrarenal abdominal aortic aneurysms (AAA) repair, the development of stent-graft complications mandates follow-up computed tomography imaging to minimize AAA-related mortality. In this single-institution report, adverse EVAR events identified in 150 consecutive patients are detailed. Early morbidity was low (<3%), with only 1 patient death on post-procedure day 2. After discharge (mean follow-up of 24 months), 2 patients died from cancer and one AAA-related mortality occurred after open conversion for stent-graft migration. Although computed tomography imaging detected no EVAR endoleak at 30 days, 19 patients developed an endoleak, including three Type I and four Type III leaks. Our institutional series review confirmed that EVAR of infrarenal AAA is a safe and valid alternative to open surgical repair, but sac embolization at the primary procedure in patients judged to be at high risk for Type II endoleak should be considered.

Improving the results of transarterial embolization of type 2 endoleaks with the embolic polymer Onyx

Introduction

Type 2 endoleaks (T2E) occur in 10 to 20% of patients after endovascular abdominal aortic aneurysm repair (EVAR) and remain a significant clinical issue.

Aim

To evaluate the efficacy and clinical outcomes of transarterial treatment of persistent type II endoleaks after EVAR using the liquid embolic Onyx.

Material and methods

From February 2012 to August 2015 transarterial T2E embolization was attempted in 22 patients (21 men, median age: 73, range: 62–88 years). Indications for treatment included an increase in the diameter of the aneurysm sac above 5 mm and a persistent endoleak observed for more than 6 months. Mean time from EVAR to endoleak treatment was 43 months (range: 2–125 months).

Results

Primary technical success was achieved in 17 (77.3%) patients and secondary technical success in 81.8%, with 0% in-hospital mortality. The mean procedure time was 95 ±48 min, with an average fluoroscopy time of 54 ±25 min. The mean amount of Onyx used was 7.5 ±6.6 ml. Clinical success was seen in 17/21 patients with follow-up imaging (80.9%). Mean follow-up time was 17 months (range: 3–38 months).

Conclusions

Onyx has been shown to effectively stabilize previous aneurysm growth as a result of the T2E in the majority of our patients. Transarterial embolization of T2E can be significantly improved as compared to previously reported results by using liquid embolic polymers such as Onyx.

Direct sac puncture versus transarterial embolization of type II endoleaks: An evaluation and comparison of outcomes

Purpose To determine the outcomes of type II endoleak embolization with aneurysm sac obliteration and whether the approach - direct sac puncture or transarterial - affects outcome. Methods A retrospective review of patients who underwent endovascular aneurysm repairs and subsequent type II endoleak embolization over 10 years was performed. Twenty-three patients (median age: 73 years, range: 40-88 years) underwent 35 embolizations. Embolization was performed with the goal of obliterating both the endoleak sac and feeding vessels. Embolization agents used include cyanoacrylate glue only (48%), glue and coils (36%), coils only (13%), and other (3%). Results Mean follow-up was 21.8 months. Patients underwent an average of 1.5 embolizations, with 35% requiring more than one. Technical success rate was 89%. Freedom from aneurysm sac expansion was achieved in 91%. Freedom from type II endoleak was accomplished in 70%. There were no ruptured aneurysms during the follow-up period. Direct sac puncture and transarterial approaches had similar incidences of aneurysm sac growth ( p = 0.74), persistent type II endoleak ( p = 0.32), and complications ( p = 0.64). However, direct sac puncture had significantly shorter fluoroscopy ( p < 0.001) and total procedure times ( p < 0.001) than transarterial embolizations. Conclusion Direct sac puncture and transarterial embolization of type II endoleak with aneurysm sac obliteration are similarly effective for the prevention of aneurysm sac growth. However, direct sac puncture is our preferred approach given its significantly shorter fluoroscopic and procedural times.

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.

Late Sac Behavior after Endovascular Aneurysm Repair for Abdominal Aortic Aneurysm

BACKGROUND

Sac behavior after endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms (AAAs) is considered as a surrogate for the risk of late rupture. The purpose of the study is to assess the sac behavior of AAAs after EVAR.

METHODS AND RESULTS

Late sac enlargement (LSE) (≥5 mm) and late sac shrinkage (LSS) (≥5 mm) were analyzed in 589 consecutive patients who were registered at 14 national centers in Japan. The proportions of patients who had LSE at 1, 3 and 5 years were 2.6% ± 0.7%, 10.0% ± 1.6% and 19.0% ± 2.9%. The proportions of patients who had LSS at 1, 3 and 5 years were 50.1% ± 0.7%, 59.2% ± 2.3% and 61.7% ± 2.7%. Multiple logistic regression analysis identified two variables as a risk factor for LSE; persistent endoleak (Odds ratio 9.56 (4.84-19.49), P <0.001) and low platelet count (Odds ratio 0.92 (0.86-0.99), P = 0.0224). The leading cause of endoleak in patients with LSE was type II.

CONCLUSIONS

The incidence of LSE is not negligible over 5 year period. Patients with persistent endoleak and/or low platelet count should carefully be observed for LSE.

CLINICAL TRIAL REGISTRATION

UMIN-CTR (UMIN000008345).

Embolization for type 2 endoleak with sac expansion after endovascular repair of abdominal aortic aneurysm: safety and effectiveness

To evaluate the safety and outcome of embolization as treatment for persistent type 2 endoleak (T2EL) occurring after abdominal aortic stent graft implantation. This retrospective study included seven consecutive patients (one female, six males, mean age 72 years, range 66–88 years) with T2EL between January 2011 and September 2012. In all, T2EL was associated with an increase more than 5 mm in the aneurysm. The endoleak cavity or feeding artery was embolized with coils and/or n-butyl cyanoacrylate. Clinical success was defined as regression or stabilization of the aneurysm sac irrespective of residual endoleaks on follow-up CT studies. At the time of T2EL intervention, mean aneurysm sac diameter was 63 mm (range 52–72 mm), and mean increase size of aneurysm sac diameter was 7 mm (range 5–13). Mean follow-up period was 6.0 ± 6.2 months (range 3–18 months). Our technical success rate was 100 %. Clinical success was obtained in 5 (71.4 %) of the seven patients. One patient was embolized three times due to sac expansion. T2EL was treated by transarterial embolization in eight procedures, and one procedure was performed by direct puncture embolization. There were no major complications; two procedures elicited minor complications: transient back pain and muscle weakness of the left lower leg. We suggest embolization was safe and effective treatment, a less invasive treatment option comparison to open repair, as one choice to address T2EL.

Characteristics and Risk Factors for Type 2 Endoleak in an East Asian Population From a Japanese Multicenter Database

BACKGROUND

Clinically distinct differences exist between East Asian and Caucasian subjects, but data for type 2 endoleak (T2EL) are limited in the East Asian population. The aim of this study was to analyze the characteristics of East Asian T2EL using a Japanese multicenter database.

METHODS AND RESULTS

Retrospective analysis of 832 endovascular aneurysm repairs performed from 2008 to 2014 were conducted. T2EL was observed in 234 cases (28.1%), and in 32 cases (3.8%) it led to sac expansion >5 mm caused by isolated T2EL (median follow-up, 35.6 months). On univariate and multivariate analysis, non-smoker status (odds ratio [OR], 2.216; P<0.001), Excluder stent graft (OR, 2.027; P<0.001), and T2EL at final angiogram (OR, 2.080; P<0.001) were risk factors for T2EL. On multivariate analysis for isolated T2EL with sac expansion, only non-smoker status remained (OR, 2.671; P<0.001). Other than T1EL, isolated T2EL was the most significant risk factor for sac expansion (OR, 18.486; P<0.001). Furthermore, out of 11 transarterial embolization procedures initiated, 4 led to rupture during follow-up.

CONCLUSIONS

East Asian T2EL had a strong relationship with non-smoker status. Also, T2EL was a significant risk factor for sac expansion, which sometimes led to rupture even after intervention. Along with the high prevalence of T2EL observed, East Asian T2EL may not always be benign.

Impact of Age and Intraluminal Thrombus Volume on Abdominal Aortic Aneurysm Sac Enlargement after Endovascular Repair

BACKGROUND

Abdominal aneurysmal sac enlargement after endovascular aortic repair (EVAR) is a critical issue. However, the predictors have not yet been fully determined. Although unrecognized, intraluminal thrombus volume (ITV) is an important index. Therefore, we retrospectively evaluated the correlation among preoperative ITV, residual type II endoleak, and sac enlargement after EVAR, based on the long-term follow-up.

METHODS

Between 2006 and 2011, 151 consecutive patients underwent EVAR at a single cardiovascular institute. Emergency surgery was performed on 7 patients (4.7%). Of 148 patients excluding 3 patients with residual type I endoleak, sac enlargement (≥5 mm progression) after EVAR was observed in 24 patients (16.2%) and 8 patients required reintervention. The mean follow-up period was 2.4 ± 1.4 years. The outer volume and enhanced luminal volume were calculated from enhanced 1-mm slice computed tomography, and the difference was defined as ITV.

RESULTS

Age (hazard ratio [HR] 1.12, 95% confidence interval [CI] 1.04-1.20, P = 0.0007), outer volume (HR 1.04, 95% CI 1.01-1.07, P = 0.0118), percentage of ITV (HR 0.90, 95% CI 0.84-0.96, P = .0027), and type II endoleak (HR 10.15, 95% CI 3.55-31.10, P < 0.0001) were isolated as predictors of sac enlargement by multivariate analysis. Also, patent inferior mesenteric artery (odds ratio [OR] 4.45, 95% CI 1.38-20.07, P = 0.0105) and percentage of ITV < 30.1% (OR 3.52, 95% CI 1.32-10.30, P = 0.0112) were detected as independent risk factors for residual type II endoleaks. Additionally, in patients without endoleak, patient age (≥83 years) was an independent risk factor for sac enlargement after EVAR (P = 0.0056).

CONCLUSION

Age and ITV percentage had significantly great impact on sac enlargement and type II endoleak after EVAR.

The Roadside Technique for Type II Endoleak Embolization 4 Years after Endovascular Aortic Aneurysm Repair

Endoleaks are the most common cause of reintervention after endovascular aortic aneurysm repair (EVAR). Type II endoleaks have been implicated as a risk factor for expansion and rupture. Several techniques have been described to manage type II endoleaks, being transarterial catheterization the most commonly used. In some cases this technique can be difficult or impossible to achieve. We report the use of a technique that offers a direct access to the aneurysm sac and the possibility of catheterization of the involved vessels or the embolization of the communication between them, even 4 years after EVAR.

Complexity of persistent type II endoleak associated with sac expansion after endovascular abdominal aortic aneurysm repair

Type II endoleak after endovascular aortic aneurysm repair still remains the Achilles' heel of the treatment, the source of which regularly is difficult to identify and treat. We present a patient with a persistent type II endoleak associated with a continuous aneurysm sac expansion after endovascular aortic aneurysm repair for which many diagnostic modalities were used during his follow-up such as duplex scan, computed tomography angiography and magnetic resonance angiography. Attempts were undertaken to treat the source of endoleak including coil micro-embolisation of lumbar arteries and subsequent open ligation of the inferior mesenteric artery, but they failed to eliminate the endoleak. Finally, a middle sacral artery was identified as the source of the endoleak. At that time, the patient was subjected to surgery for sigmoid carcinoma, and simultaneously, a ligation of the sacral artery was undertaken which eventually eliminated the endoleak completely. This case highlights that type II endoleak may be evoked by various sources and there can be a great difficulty to identify these feeding vessels; thus, careful planning for its management is mandatory.

Duplex Ultrasound versus Computed Tomography for the Postoperative Follow-Up of Endovascular Abdominal Aortic Aneurysm Repair. Where Do We Stand Now?

In the last decade, endovascular aneurysm repair (EVAR) has rapidly developed to be the preferred method for infrarenal abdominal aortic aneurysm repair in patients with suitable anatomy. EVAR offers the advantage of lower perioperative mortality and morbidity but carries the cost of device-related complications such as endoleak, graft migration, graft thrombosis, and structural graft failure. These complications mandate a lifelong surveillance of EVAR patients and their endografts. The purpose of this study is to review and evaluate the safety of color-duplex ultrasound (CDU) as compared with computed tomography (CT), based on the current literature, for post-EVAR surveillance. The post-EVAR follow-up modalities, CDU versus CT, are evaluated questioning three parameters: (1) accuracy of aneurysm size, (2) detection and classification of endoleaks, and (3) detection of stent-graft deformation. Studies comparing CDU with CT scan for investigation of post-EVAR complications have produced mixed results. Further and long-term research is needed to evaluate the efficacy of CDU versus CT, before CDU can be recommended as the primary imaging modality for EVAR surveillance, in place of CT for stable aneurysms.

Type 2 Endoleaks Post-EVAR: Current Evidence for Rupture Risk, Intervention and Outcomes of Treatment

Type 2 endoleaks (EL2) are the most commonly encountered endoleaks following EVAR. Despite two decades of experience, there remains considerable variation in the management of EL2 with controversies ranging from if to treat, when to treat and how to treat. Here, we summarise the available evidence, describe the treatment techniques available and offer guidelines for management.

Influencing Factors for Abdominal Aortic Aneurysm Sac Shrinkage and Enlargement after EVAR: Clinical Reviews before Introduction of Preoperative Coil Embolization

BACKGROUND

We previously reported effectiveness of coil embolization (CE) to aortic branched vessels before endovascular aortic repair (EVAR) for abdominal aortic aneurysm (AAA) because of significant shrinkage of aneurysmal sac. In this study, we investigated EVAR cases to clarify influential factors of aneurysmal shrinkage and enlargement.

METHODS

148 consecutive cases before the introduction of CE were retrospectively reviewed based on the presence of PT2EL (persistent type 2 endoleak) and change in sac diameter after EVAR by multivariate analysis.

RESULTS

(A) PT2EL risk factors were patent inferior mesenteric artery (IMA) and thinner mural thrombus inside aneurysmal sac. (B) Sac enlargement risk factors were antiplatelet intake, PT2EL, and female gender. (C) Sac shrinkage predictive factors were the absences of thoracic aortic aneurysm, antiplatelet intake, PT2EL, and coronary artery disease.

CONCLUSION

CE to IMA was considered to be effective because patent IMA and antiplatelet intake were significant risk factors for sac enlargement. So, more meticulous therapeutic strategy, including treatment priority (AAA first or CAD first) and choice of treatment (EVAR vs. AAA) based on anatomical features of AAA was required to improve late outcomes.

CT Findings of Risk Factors for Persistent Type II Endoleak from Inferior Mesenteric Artery to Determine Indicators of Preoperative IMA Embolization

PURPOSE

To identify the computed tomography (CT) findings of persistent type II endoleak from the inferior mesenteric artery (IMA) which indicate the need for preoperative IMA embolization.

MATERIALS AND METHODS

Included were 120 patients (96 males, 49-93 years old, mean: 77.7) who underwent endovascular aortic aneurysm repair (EVAR) between June 2007 and October 2010. The relationship between persistent type II endoleak and CT findings of IMA orifice was examined.

RESULTS

CT showed no type II endoleak from IMA in 106 patients (89%; Group N), and transient type II endoleak from IMA in 10 patients (8.3%; Group T). CT showed persistent type II endoleak from IMA in 4 patients (3.3%; Group P) and three of them underwent reintervention. Univariate Cox-Mantel test analysis indicated that stenosis (p = 0.0003) and thrombus (p = 0.043) in IMA orifice were significant factors for persistent type II endoleak. The ratios of patients with proximal IMA more than 2.5 mm diameter in Groups N, Y, and P were 26/106 (24%), 5/10 (50%) and 4/4 (100%), respectively.

CONCLUSION

Indicators for embolization of IMA prior to EVAR for the prevention of type II endoleak appear to be: (1) more than 2.5 mm in diameter and (2) no stenosis due to calcification or mural thrombus in IMA orifice.