Risk Factors for Early and Late Type Ib Endoleak Following Endovascular Abdominal Aortic Aneurysm Repair

Five-year outcomes for bell bottom, iliac branch endoprosthesis, and coil and cover approaches from the GREAT registry

OBJECTIVE

There are a variety of methods used today to treat common iliac aneurysms with endovascular techniques. Of these approaches, little is known about whether a particular limb strategy influences endoleak, reintervention, or aneurysm regression rates. We present 5-year data comparing endoleak, stent graft migration, fracture, aneurysm sac dynamics, and aortic rupture rates among patients treated with bell bottom limbs (BB), iliac branch endoprosthesis (IBE), and coil and cover (CC) approaches from the Global Registry for Endovascular Aortic Treatment registry. Secondary end points were all-cause mortality, stroke, reintervention, and paraplegia.

METHODS

Subjects from the GORE Global Registry for Endovascular Aortic Treatment were enrolled over a 5-year period from October 2017 to August 2022. We included 924 subjects in this study. Statistical data was generated on R software and limb groups were compared using the Pearson's χ2 test and the Kruskal-Wallis rank-sum test.

RESULTS

We found no statistical difference in endoleak rates, stent graft migration, fracture, or aortic rupture when stratified by limb strategy. There was no difference between limb approaches with regard to aneurysm sac dynamics among those with abdominal aortic aneurysms and common iliac aneurysms. Similarly, no statistical difference between limb strategies was found in all-cause mortality, stroke, paraplegia, or reintervention rates. Among patients that required an additional graft during reintervention, the highest rates were found within the IBE group 8.6%, compared with BB group 2.2% and CC group 1.3% (P = .006).

CONCLUSIONS

Overall, there was no difference among limb strategies in endoleak rates, stent graft migration, aneurysm sac dynamics, aortic rupture rates, or our secondary end points. Increased rates of reintervention requiring an additional graft within the IBE group is noteworthy and must be weighed against the adverse effects of hypogastric sacrifice with the CC approach or potentially less advantageous seal zones in the BB approach. This finding suggests that all limb approaches have equivalent effectiveness in managing the aneurysmal common iliac artery; thus, the choice of limb strategy should be individualized and remain at physician discretion. Future research should include a more robust sample size to reproduce these findings.

Endotension Following Endovascular Aneurysm Repair: Retrospective Review of Treatment and Clinical Outcome

Purpose

: Endotension is a rare late complication characterized by an increase in sac size without any type of endoleak following endovascular aortic aneurysm repair (EVAR). Due to its rarity, few studies have demonstrated the mechanism behind and the management of endotension. In this study, we aimed to better understand the treatment and the long-term outcome of endotension in a single-center cohort.

Materials and Methods

: This study was designed for a retrospective review of the patients diagnosed with endotension between January 2006 and December 2017. The study patients were categorized into two groups (primary versus secondary) based on the presence of any type of endoleak before the diagnosis of endotension. We collected data related to endotension treatment, intraoperative findings, and long-term outcomes.

Results

: In a cohort of 15 patients diagnosed with endotension following EVAR, eight were classified into the primary endotension (PE) group without prior endoleak, and seven exhibited secondary endotension (SE). Among the eight PE patients, endovascular intervention for a preemptive purpose was conducted in six patients; however, three (50%) showed continuous sac expansion and finally received open conversion. Overall, eight patients (five in PE and three in SE) underwent open conversion, and one (12.5%) presented with an undetected endoleak during the operative findings. Postoperative morbidity was observed in three patients with no operative mortality.

Conclusion

: Endotension can be managed initially through simple observation for changes on serial images, along with preemptive endovascular intervention. However, surgical intervention should be considered for patients with specific indications including continuous aneurysm sac enlargement, presence of symptoms, suspicions of migration of stent-graft with endoleak, and infection.

Management of Endoleaks After Elective Infrarenal Aortic Endovascular Aneurysm Repair: A Review

Importance

Endovascular aneurysm repair (EVAR) is the dominant treatment strategy for abdominal aortic aneurysms, encompassing 80% of all repairs in the United States. Endoleaks are ubiquitous and affect 30% of patients treated by EVAR, potentially leading to sac enlargement and increased risk of rupture. The care of EVAR patients requires long-term surveillance by a multidisciplinary team. Accordingly, physicians should be familiar with the fundamentals of endoleak management to achieve optimal outcomes, including timely referral for remediation or providing counseling and reassurance when needed.

Observations

PubMed and the Cochrane database were searched for articles published between January 2002 and December 2022 in English, addressing epidemiology, diagnosis, and management of endoleaks after EVAR. Endoleaks can be detected intraoperatively or years later, making lifelong surveillance mandatory. Type I and III have the highest risk of rupture (7.5% at 2 years and 8.9% at 1 year, respectively) and should be treated when identified. Intervention should be considered for other types of endoleak when associated with aneurysm sac growth larger than 5 mm based on current guidelines. Type II endoleaks are the most common, accounting for 50% of all endoleaks. Up to 90% of type II endoleaks resolve spontaneously or are not associated with sac enlargement, requiring only observation. Although the risk of rupture is less than 1%, cases that require reintervention are challenging. Recurrence is common despite endovascular treatment, and rupture can occur without evidence of sac growth. Type IV endoleaks and endotension are uncommon, are typically benign, and primarily should be observed.

Conclusions and Relevance

Endoleak management depends on the type and presence of sac expansion. Type I and III endoleaks require intervention. Type II endoleaks should be observed and treated selectively in patients with significant sac expansion. Since endoleaks can appear any time after EVAR, at least 1 contrast-enhanced computed tomographic angiogram or duplex ultrasound by an experienced laboratory is recommended every 5 years.

Incidence, Risk Factors, and Prognostic Impact of Type Ib Endoleak Following Endovascular Repair for Abdominal Aortic Aneurysm: Scoping Review

OBJECTIVE

The primary objectives of this scoping review were to assess the rate of and risk factors for type Ib endoleak and to evaluate the extent of the evidence base that links type Ib endoleak to short and long term outcomes in patients undergoing endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA).

METHODS

Potentially eligible studies were searched in the Cochrane Central Register of Controlled Trials, MEDLINE, Web of Science Core Collection, SciELO Citation Index, Russian Science Citation Index, and KCI-Korean Journal Database. A scoping review was performed according to PRISMA extension for Scoping Reviews.

RESULTS

A total of 27 articles (four prospective registries and 23 retrospective cohort studies) dealing with type Ib endoleak were included in the final analysis. The number of patients reported on was 7 197, with follow up ranging between 12 months and 93 months. The reported frequency of type Ib endoleak in patients treated with EVAR ranged from 0% to 8%, Patient and or procedure related factors associated with risk of type Ib endoleak were (1) common iliac artery (CIA) diameter ˃ 18 mm requiring use of flared stent graft limbs (FLs) ˃ 20 mm, (2) length of CIA landing zone ˂ 20 mm, (3) marked iliac tortuosity, and (4) large initial AAA diameter. Depending on the study, 50 - 100% of type Ib endoleaks were corrected by endovascular means, with a reported immediate technical success of 100% in the studies providing this information.

CONCLUSION

Type Ib endoleak after EVAR has been reported to occur in 0 - 8% of cases. Several anatomical features, including CIA diameter ˃ 18 mm or requiring the use of FLs ˃ 20 mm, length of CIA landing zone ˂ 20 mm, marked iliac tortuosity, and large initial AAA diameter, could increase the risk of type Ib endoleak and may require alternative therapeutic options and or more stringent follow up. Therefore, this updated scoping review provides a comprehensive summary of the frequency, risk factors, prognosis, and treatment of type Ib endoleaks, and has identified knowledge gaps in the literature to guide further studies.

Use of Secondary Iliac Branch Devices after Previous Endovascular Abdominal and Thoraco-Abdominal Aortic Aneurysm Repair

OBJECTIVE

To assess the safety and effectiveness of iliac branch devices (IBDs), as secondary procedure, for the treatment of type Ib endoleak or evolution of iliac artery disease after prior endovascular aortic repair (EVAR) for thoraco-abdominal (TAAAs) or abdominal aortic aneurysms (AAAs).

METHODS

A multicentre observational study of three European centres. The study included 75 patients (age 71 ± 9 years, 96% men) with previous EVAR (n = 64, 85%) or fenestrated or branched (FB) EVAR (n = 11, 15%). Overall, 88 IBDs were implanted to treat aneurysmal iliac artery evolution in 40 (53%) and type Ib endoleak in 35 (47%) cases, respectively. Thirteen (17%) patients received bilateral IBDs. Internal iliac artery (IIA) catheterisation was done through a transaxillary access (n = 82, 93%) or up and over (n = 6, 7%) technique. The primary endpoint was technical success. Secondary endpoints were 30 day major adverse event, early and long term freedom from re-intervention and target vessel instability.

RESULTS

All procedures were technically successful (100%). During hospitalisation, there were four (5%) major adverse events and three (4%) early re-interventions, but no death, stroke, or damage to previous endografts. The median follow up was 47 (interquartile range 42) months, and the five year survival rate was 78 ± 6% with no aortic related death. Cox's regression analysis showed pre-operative renal function impairment (hazard ratio [HR] 3.4; 95% confidence interval [CI] 1.1 - 10.1; p = .033), and primary TAAA repair (HR 6.1; 95% CI 1.6-22.3; p = .006) as independent factors for long term mortality. Freedom from re-interventions was 85 ± 4% at five years with 11 (12%) cases (five endoleaks, four IBD thromboses, two stenoses). IIA instability was reported in three (3%) limbs and freedom from IIA instability was 95 ± 3% after 60 months.

CONCLUSION

Secondary IBD after EVAR is a safe and effective procedure with high technical success and low complication rates. The technique of choice to revascularise the IIA seems not to affect early and follow up results. Long term durability of IBD repair is acceptable with low rates of IIA re-intervention.

Iliac branch device to treat type IB endoleak with a brachial access or an "up-and-over" transfemoral technique

PURPOSE

This study aimed to review the results of secondary IBD (iliac branch device) implantation in patients with type IB endoleak after prior fenestrated and/or branched or infrarenal endovascular aortic repair (F/B-EVAR or EVAR), using either brachial access or an "up-and-over" transfemoral technique.

METHODS

A retrospective single centre analysis was conducted between Jan 2016 and Oct 2021 including consecutive patients that underwent IBD to correct a type IB endoleak after prior EVAR or F/B-EVAR. Groups were defined by arterial access which was either brachial (group 1) or transfemoral (group 2). All IBD implanted were manufactured by Cook Medical (INC, Bloomington, IN, USA). Demographics, anatomical features, technical success, and 30-day major adverse events (MAE) were recorded according to the current SVS standards. Survival curves according to Kaplan-Meier were calculated. Branch instability was a composite endpoint of any IIA branch-related complication or reintervention indicated to treat endoleak, kink, disconnection, stenosis, occlusion or rupture.

RESULTS

Overall, 28 patients (93% male, median age 74 years) receiving 32 IBDs were included, with 14 patients in each group. Prior endovascular aortic repairs were 23 EVAR and 5 F/B-EVAR, with time from initial repair being 58 months [48, 70]. Median pre-IBD maximal aneurysm diameter was 63.5 mm [59.0, 78.0]. Patients' baseline characteristics were similar in both groups except for pulmonary status. All procedures were performed in a hybrid operative room. Median total operating time, fluoroscopy time and dose area product were 120 min [86, 167], 23 min [15, 32] and 54 Gy.cm2 [40, 62], respectively. Total operating time was shorter in group 2 (p=0.006). Technical success rate was 100% and no early death reported. One 30-day MAE occurred including a medically treated colonic ischemia (group 2). Aortic-related secondary interventions were required in 7 patients (5 in group 1 and 2 in group 2) including 3 surgical explantations. Median follow-up was 31 months [24, 42] and 6 months [3, 10] in group 1 and 2, respectively. In group 1, 2-year freedom from aortic-related secondary intervention and IIA branch instability were 84.6% [67.1-100] and 92.3% [78.9-100], respectively. In group 2, 6-month freedom from aortic-related secondary intervention and IIA branch instability were 87.5% [67.3-100] and 91.7% [77.3-100], respectively.

CONCLUSION

The secondary implantation of IBD to correct distal type I endoleak of previous aortic stent-graft is safe with a high technical success rate. The "up-and-over" technique could be considered as an alternative to the brachial access in patients with suitable anatomy.

[Endoleaks in endovacular treatment of infrareneral abdominal aortic aneurysm (part I)]

We analyzed the PubMed, Scopus databases and the eLIBRARY electronic library regarding appropriate literature data. In the first part, modern classifications of endoleaks type 1 and 2 after stenting of infrarenal aortic aneurysm are considered. We described causes, risk factors and effectiveness of various treatment options.

Impact of target visceral vessel anatomical configuration on early complications following endovascular repair of thoracoabdominal aortic aneurysms

Impact of target visceral vessel anatomical configuration on early complicatins following endovascular repair of thoracoabdominal aortic aneurysms Objectives: Fenestrated and branched endovascular aortic repair (fEVAR-bEVAR) is a viable treatment option for thoracoabdominal aortic aneurysms but target visceral stent (TVS) endoleak and thrombosis remain a limiting factor. This study aims to evaluate TVS anatomy impact on one-year risk of thrombosis and endoleak.

METHODS

Patients treated with fEVAR-bEVAR for thoracoabdominal aneurysms between 2008-2020 in our centre were enrolled. We recorded comorbidities, operative details, one-month postoperative CT scan (anatomical reference), and TVS behaviour: thrombosis and endoleak at one-year follow-up. For each TVS, different points were identified using a centre-lumen-line: (A) TVS origin, (B) end of branch/fenestration, (C) visceral vessel entry, (D) end of TVS, (E) 1-cm distally. We analyzed TVS tortuosity ((centre-lumen-line/straight distance)-1, in %), image vector analysis of each segment in 2D (antero-posterior, left-right) and 3D (craneo-caudal displacement), and centre-lumen-line analysis (bending in ABC and CDE). Three independent observers performed a blind analysis, and anatomical differences between bEVAR/fEVAR, and cases with/without 1-year thrombosis and TVS endoleak, were compared using Kaplan-Meier curves (Log-Rank test), and T-Test/Wilcoxon signed-ranks test respectively.

RESULTS

54 patients (72±713 years mean age; 182 TVS: 50 branches, 132 fenestrations) met the inclusion criteria. bEVAR cases had longer stents, with more caudal 3D angulation and greater ABC angulated segment. After excluding bEVAR cases (low case number), 97 fEVAR TVS were analyzed. Five thrombosis and seven endoleaks were observed. While anatomical configuration showed no association to thrombosis, it was related to endoleak: these cases presented more tortuous stents (5.97%±0.10, 21.40%±0,22, P=.011), with more angulated centre-lumen-line at ABC segment (5.69°±15.77°, 7.18°±7.77°, P=.012), and more upward-pointing stents in the origin of the stent (AB: 89.07°±24.46°, 109.09°±16.56°, P=.012; BC: 87.86°±21.10°, 113.11°±22.23°, P=.026).

CONCLUSIONS

Anatomical configuration of the TVS is associated with stent type I-III endoleak, but not thrombosis, at one-year following fEVAR. Cases with endoleak presented more tortuous stents, with a more angulated exit from the endograft and upward-pointing of the origin of the stent.

Ipsilateral Iliac Branch Repair Using a Looped Wire, Precannulated Gate Technique

PURPOSE

To describe a novel, entirely ipsilateral femoral technique for distal endograft extension using the Gore Iliac Branch Endoprosthesis.

TECHNIQUE

Femoral arterial access is obtained on the side of the intended repair, and a 16F sheath is inserted over a stiff wire. A looped wire is used to pre-cannulate the internal gate of the IBE device prior to insertion, and the device is then positioned and deployed. This through-wire guides access over the IBE flow divider and into the internal gate with a steerable sheath. The internal iliac artery is then selected, and a Viabahn VBX balloon-expandable stent (W.L. Gore, Flagstaff, AZ) is advanced into position and deployed. We present the successful completion of this technique in 4 patients.

CONCLUSION

This novel technique allows distal endograft extension with an IBE device using only ipsilateral femoral access and is particularly useful for patients with aneurysmal iliac degeneration in the setting of prior open or endovascular aneurysm repair. This eliminates the need for upper extremity access or contralateral femoral access and navigation across the steep flow divider.