Aneurysm Sac Enlargement after Endovascular Abdominal Aortic Aneurysm Repair

Five-Year Results for Abdominal Aortic Aneurysm Repair with the GORE® EXCLUDER® Device: Insights from the Gore Global Registry for Endovascular Aortic Treatment (GREAT)

BACKGROUND

The early postoperative benefits of endovascular aneurysm repair (EVAR) have been well established but questions remain regarding its durability at mid-term and long-term time points. Long-term results in real-world use of EVAR outside of randomized trial data are limited. This study used the Global Registry for Endovascular Aortic Treatment registry to explore the 5-year outcomes with the GORE EXCLUDER device in real-world clinical circumstances.

METHODS

All patients within the Global Registry for Endovascular Aortic Treatment registry who underwent an infrarenal abdominal aortic aneurysm repair with the GORE EXCLUDER device were included in this study. Baseline characteristics and demographic information of the cohort were collected. End points included mortality (all-cause and aneurysm-related), serious endoleaks, aneurysm sac diameter, endograft integrity (fracture, compression, migration), post-EVAR aortic rupture, device-related reintervention, conversion to open repair, graft explantation, and major adverse cardiovascular events.

RESULTS

A total of 3,216 patients were included in this analysis. The cohort reflected a significantly comorbid population with 46% of patients reaching a Charlson Comorbidity Index score of ≥5. Follow-up at 5 years was 60% of eligible participants. The freedom from aortic-related mortality was at 98.8% and overall survival was 71.2%. Postoperative major adverse cardiovascular events occurred in 49 (1.5%) patients. Device-related intervention through 5 years was 7.2% and the overall serious endoleak rate was 6.8%. Less than 1% of patients required an open conversion/revision and aortic rupture following device placement occurred in 15 (0.5%) patients. Aneurysm sac regression was achieved in 58.1% of patients at 5 years, and stability/absence of growth was observed in 83.6% at 5 years.

CONCLUSIONS

This study supports the durability of the GORE EXCLUDER device through 5 years with negligible incidence of graft integrity compromise and low aortic/device-related reintervention rates. Furthermore, the efficacy of the device is highlighted with low aortic-related mortality and high sac regression/stability diameter through 5 years.

Indication and Outcome of Late Open Conversion after Abdominal Endovascular Aortic Repair

BACKGROUND

Endovascular aortic repair (EVAR) has become the standard of care for patients with infrarenal aortic aneurysms over the last 2 decades. Endograft technology and treatment of complications like endoleaks, graft migration, or graft occlusion developed over time. However, sometimes open surgical conversion maybe required. Our aim was to analyze the indications, the technical aspects and outcomes in patients who underwent open conversion after EVAR with different types and generations of endografts.

METHODS

This retrospective single-center study reviewed all patients who underwent EVAR from 2004 to 2020. Open surgical conversions >1 month post EVAR were identified. Conversions for graft infection were excluded. Indications for conversion and operative technique were analyzed. Primary endpoint of the study was 30-day mortality. Secondary endpoints were re-interventions and follow-up mortality.

RESULTS

During 2004 and 2020, 443 consecutive EVARs were performed, and 28 patients required open surgical conversion, with an additional 3 referred from other hospitals (N = 31). The median age was 75 (range 58-93); 94% were male. Conversion was performed after a median time of 55 months (range 16-209). Twenty patients underwent elective and 11 emergency conversion. Indications for open conversion were graft migration, respectively, disease progression with endoleak type Ia and/or Ib in 52% (16/31) and sac expansion due to endoleak type II in 26% (8/31). Of the 31 patients, 17 (55%) had at least one previous endovascular re-intervention. All patients met the device-specific instructions for use for each implanted endograft. In-hospital intervention rate was 16% (5/31). Thirty-day mortality rate was 3% (1/31) with one patient died due to multiorgan failure after rupture with complete endograft replacement. Five patients (16%) died during follow-up. Mid-term follow-up was 47.5 months (range 24-203) with estimated cumulative survival rates of 97%, 89%, and 84%, at 1, 3, and 5 years, respectively.

CONCLUSIONS

Late open conversion remains a valuable treatment option and can be performed safely in elective and emergency setting with a low early mortality. Lifelong surveillance and prompt intervention when necessary are essential in ensuring optimal outcomes after EVAR and preventing the need for emergent conversions.

Laparoscopic Ligation of the Inferior Mesenteric Artery: A Systematic Review of an Emerging Trend for Addressing Type II Endoleak Following Endovascular Aortic Aneurysm Repair

Background/Objectives: this systematic review aims to explore the efficacy and safety of the laparoscopic ligation of the inferior mesenteric artery (IMA) as an emerging trend for addressing a type II endoleak following endovascular aortic aneurysm repair (EVAR). Methods: A comprehensive literature search was conducted across several databases including Medline, Scopus, and the Cochrane Central Register of Controlled Trials, adhering to the PRISMA guidelines. The search focused on articles reporting on the laparoscopic ligation of the IMA for the treatment of a type II endoleak post-EVAR. Data were extracted regarding study characteristics, patient demographics, technical success rates, postoperative outcomes, and follow-up results. Results: Our analysis included ten case studies and two retrospective cohort studies, comprising a total of 26 patients who underwent a laparoscopic ligation of the IMA between 2000 and 2023. The mean age of the cohort was 72.3 years, with a male predominance (92.3%). The mean AAA diameter at the time of intervention was 69.7 mm. The technique demonstrated a high technical success rate of 92.3%, with a mean procedure time of 118.4 min and minimal blood loss. The average follow-up duration was 19.9 months, with 73% of patients experiencing regression of the aneurysmal sac, and no reports of an IMA-related type II endoleak during the follow-up period. Conclusions: The laparoscopic ligation of the IMA for a type II endoleak following EVAR presents a promising, minimally invasive alternative with high technical success rates and favorable postoperative outcomes. Despite its potential advantages, including reduced contrast agent use and radiation exposure, its application remains limited to specialized centers. The findings suggest the need for further research in larger prospective studies to validate the effectiveness of this procedure and potentially broaden its clinical adoption.

Midterm outcomes of physician-modified endovascular stent grafts for the treatment of complex abdominal aortic aneurysms in Korea: a retrospective study

Purpose

Physician-modified endovascular stent grafts (PMEG) are a good treatment option for complex abdominal aortic aneurysms (AAAs), especially in high-risk patients not amenable to open repair, and when commercial fenestrated devices are not available. We report our single-center experience with PMEG for the treatment of complex AAAs.

Methods

We retrospectively reviewed patients who underwent PMEG repair for AAA from November 2016 to September 2020 at our institution. Demographic data, anatomic characteristics, perioperative and postoperative outcomes, major adverse events, and 30-day mortality were analyzed.

Results

We identified 12 patients who underwent PMEG for complex AAA. The mean age was 74 years and the mean maximal AAA diameter was 58.1 mm. Indications for treatment included 4 impending or contained ruptures, 2 mycotic aneurysms, and 6 symptomatic cases. The technical success rate was 91.7%. Aneurysm sac regression was observed in 7 patients (58.3%), including 2 cases of complete regression. There was 1 aneurysm-related mortality at 3 months due to mycotic aneurysm. Also, there was 1 postoperative complication case of transient renal failure requiring temporary dialysis. At 1 year, there was 1 branch occlusion from the initial failed cannulation case and 2 type 1A endoleaks, and there was 1 case of open explantation.

Conclusion

PMEG showed a low technical failure rate and acceptable midterm stent durability and sac stability, comparable to conventional endovascular aneurysm repair. Despite the small number of cases, there was a tendency for a high sac regression rate, although longer follow-up is needed.

Endograft position and endoleak detection after endovascular abdominal aortic repair with low-field tiltable MRI: a feasibility study

BACKGROUND

Abdominal aortic endoleaks after endovascular aneurysm repair might be position-dependent, therefore undetectable using supine imaging. We aimed to determine the feasibility and benefit of using a low-field tiltable magnetic resonance imaging (MRI) scanner allowing to study patients who can be imaged in both supine and upright positions of endoleaks.

METHODS

Ten EVAR patients suspected of endoleak based on ultrasound examination were prospectively included. MRI in upright and supine positions was compared with routine supine computed tomography angiography (CTA). Analysis was performed through (1) subjective image quality assessment by three observers, (2) landmark registration between MRI and CTA scans, (3) Euclidean distances between renal and endograft landmarks, and (4) evaluation of endoleak detection on MRI by a consensus panel. Statistical analysis was performed by one-way repeated measures analysis of variance.

RESULTS

The image quality of upright/supine MRI was inferior compared to CTA. Median differences in both renal and endograft landmarks were approximately 6-7 mm between upright and supine MRI and 5-6 mm between supine MRI and CTA. In the proximal sealing zone of the endograft, no differences were found among all three scan types (p = 0.264). Endoleak detection showed agreement between MRI and CTA in 50% of the cases, with potential added value in only one patient.

CONCLUSIONS

The benefit of low-field upright MRI for endoleak detection was limited. While MRI assessment was non-inferior to standard CTA in detecting endoleaks in selected cases, improved hardware and sequences are needed to explore the potential of upright MRI in patients with endoleaks.

RELEVANCE STATEMENT

Upright low-field MRI has limited clinical value in detecting position-dependent endoleaks; improvements are required to fulfil its potential as a complementary modality in this clinical setting.

KEY POINTS

• Upright MRI shows potential for imaging endoleaks in aortic aneurysm patients in different positions. • The image quality of upright MRI is inferior to current techniques. • Upright MRI complements CTA, but lacks accurate deformation measurements for clinical use. • Advancements in hardware and imaging sequences are needed to fully utilise upright MRI capabilities.

2022 ACC/AHA guideline for the diagnosis and management of aortic disease: A report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate. Structure: Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

An Objective and Repeatable Sac Isolation Technique for Comparing Biomechanical Metrics in Abdominal Aortic Aneurysms

(1) Abdominal aortic aneurysm (AAA) biomechanics-based metrics often reported may be over/under-estimated by including non-aneurysmal regions in the analyses, which is typical, rather than isolating the dilated sac region. We demonstrate the utility of a novel sac-isolation algorithm by comparing peak/mean wall stress (PWS, MWS), with/without sac isolation, for AAA that were categorized as stable or unstable in 245 patient CT image sets. (2) 245 patient computed tomography images were collected, segmented, meshed, and had subsequent finite element analysis performed in preparation of our novel sac isolation technique. Sac isolation was initiated by rotating 3D surfaces incrementally, extracting 2D projections, curve fitting a Fourier series, and taking the local extrema as superior/inferior boundaries for the aneurysmal sac. The PWS/MWS were compared pairwise using the entire aneurysm and the isolated sac alone. (3) MWS, not PWS, was significantly different between the sac alone and the entire aneurysm. We found no statistically significant difference in wall stress measures between stable (n = 222) and unstable (n = 23) groups using the entire aneurysm. However, using sac-isolation, PWS (24.6 ± 7.06 vs. 20.5 ± 8.04 N/cm2; p = 0.003) and MWS (12.0 ± 3.63 vs. 10.5 ± 4.11 N/cm2; p = 0.022) were both significantly higher in unstable vs. stable groups. (4) Our results suggest that evaluating only the AAA sac can influence wall stress metrics and may reveal differences in stable and unstable groups of aneurysms that may not otherwise be detected when the entire aneurysm is used.

"Large Diameter" Aortic Endografts Are Associated With Aneurysm Sac Expansion

INTRODUCTION/OBJECTIVES

The purpose of this study was to evaluate the association between aortic endograft diameter and long-term outcomes following endovascular aneurysm repair (EVAR) performed in accordance with manufacturer instructions for use (IFU).

METHODS

Retrospective review of consecutive patients undergoing on-IFU EVAR (2000-2018) was performed to facilitate a comparative analysis of long-term patient outcomes based on device diameter. "Large diameter" devices were defined as >34mm. The primary outcome of interest was freedom from sac expansion throughout long-term follow-up. Analyses included standard bivariate analyses, Kaplan Meier with log-rank comparison, and Cox proportional hazards multivariate analysis.

RESULTS

A total of 1099 underwent on-IFU EVAR from 2000-2018. Follow-up data were available for 980 patients. Of these, 75 patients (7.6%) were treated with >34 mm devices. There were no significant differences in demographics or co-morbidities between the 2 groups, although pre-operative AAA size was greater in patients undergoing implantation of >34mm devices (58 ± 8.5 mm vs. 56 ± 17.4 mm; P=0.05). Median follow-up was 10.3 years. Patients with grafts >34 mm had reduced freedom from sac expansion throughout follow-up (P=0.038). There were no significant differences in reintervention rates, open conversion, or rupture when stratified by graft diameter. Multivariate Cox Regression identified patient age, pre-operative AAA size, need for reintervention, and use of >34 mm endografts as independent factors associated with expansion.

CONCLUSION

The use of large diameter aortic endografts is associated with higher rates of sac expansion during long-term follow-up. While there is undoubtedly a role for large diameter graft use in selected patients, it is important to recognize that these devices were typically approved post-hoc without the same regulatory scrutiny of smaller endografts. These findings underscore the importance of ongoing surveillance for patients treated with >34 mm grafts, irrespective of compliance with manufacturer IFU.

Surgical Findings and Outcomes of Endotension following Endovascular Aneurysm Repair

BACKGROUND

Endotension is one of the detrimental complications after endovascular aneurysm repair (EVAR) and surgical management has been considered as standard of care. However, there is a paucity of data regarding the findings and outcomes of such surgical intervention. The aim of this study was to investigate intraoperative findings and outcomes of surgical treatment for endotension after EVAR.

METHODS

Between January 2005 and October 2018, of the 708 patients who underwent EVAR for aneurysm aortic aneurysm; 12 patients (mean age of 76.1; range 66-88) who underwent open repair for endotension were retrospectively analyzed. The anatomical characteristics of the aorta and surgical findings were reviewed. The rates of early and late procedural complications, and overall mortality were evaluated.

RESULTS

The median interval between the EVAR and surgical conversion was 45.9 months (range 17.1-46.9). Three of the twelve patients underwent emergency surgery due to aneurysm rupture. The median aneurysm sac size, the proximal neck diameter, and the proximal neck length before EVAR were 64 mm, 23.5 mm, and 30.5 mm, respectively, that changed before open repair to 93.5 mm (p = .02), 25 mm (p = .011), and 23 mm (p = .003), respectively. In four of the twelve patients, radiographically undetected endoleak was identified during surgery to be Type Ia, Ib, II, and III, respectively. The rates of early and late procedural complications, and overall mortality were 8.3%, 8.3% and 8.3%, respectively.

CONCLUSIONS

Patients with endotension have a risk of delayed endoleak and aneurysm rupture; secondary intervention should be performed in such cases to prevent fatal complications. Surgical treatment appears to be a curative treatment for endotension with favorable outcomes. In addition, the possibility of an undetected endoleak should be considered as a potential cause of endotension.

Relining of infrarenal stent-graft with preloaded modified Gore Excluder for occult endoleak with sac expansion

Endoleaks remain one of the most common indications for reintervention after endovascular aortic repair. Occasionally, aneurysm sac expansion will occur in the absence of a visible endoleak or due to endotension. We describe a case of continued sac expansion without an identifiable endoleak after endovascular aortic repair. Technical challenges during the case included a short distance from the renal arteries to the flow divider and a significant metal artifact. These challenges were addressed by shortening the gate of a Gore Excluder (W.L. Gore & Associates, Flagstaff, Ariz) to the desired length. The contralateral gate was preloaded to allow for use of the snare-ride technique for gate cannulation and overcome the metal artifact that was hindering visualization.

Embolization of Type 2 Endoleaks in the Abdominal Aorta Using Ethylene Vinyl Alcohol Copolymer

BACKGROUND

 Type 2 endoleaks (T2EL) are the most frequent complication following endovascular aortic repair. Multiple studies primarily deal with the technical and clinical success of the embolization of persisting T2EL, thereby revealing controversial outcomes. Current reports rarely focus on the detailed execution of such a complex interventional procedure with respect to the difficult anatomic setting.

METHODS

 The present review provides an in-depth depiction and evaluation of the interventional methodology of the embolization of T2EL in the abdominal aorta with use of ethylene vinyl alcohol copolymer (EVOH). Complicating anatomic conditions are taken into account as well as technical and clinical success rates.

RESULTS

 Using the transarterial approach, there are at least 4 different pathways to access the nidus of a T2EL. CT-guided direct puncture of the aneurysm sac provides an alternative method of high technical success. EVOH with its slow solidification characteristics enables good control to achieve complete filling of the T2EL. During the intervention, however, it remains difficult to meet exactly the embolization endpoint, especially in large T2ELs.

CONCLUSION

 T2EL embolization using EVOH is an effective treatment with low major complication rates when conducted by skilled interventionists with detailed knowledge of diverse complex access routes.

KEY POINTS

  · Many roads lead to Rome to access the nidus of a T2EL including diverse complex transarterial pathways and direct aneurysm sac puncture.. · Ethylene vinyl alcohol co-polymer enables good control for slow filling of the nidus with low risk of major complications.. · Identification of the embolization endpoint remains difficult during the procedure and may result in secondary interventions.. · Successful T2EL embolization requires detailed knowledge of all access routes to the nidus and skilled handling of liquid embolics..

CITATION FORMAT

· Nolte-Ernsting C, Mecklenbeck F, Stehr A. Embolization of Type 2 Endoleaks in the Abdominal Aorta Using Ethylene Vinyl Alcohol Copolymer. Fortschr Röntgenstr 2021; DOI: 10.1055/a-1502-7883.

Endotension: What do we know and not know about this enigmatic complication of endovascular aneurysm repair

As the use of endovascular approaches to treat aneurysm repair continues to increase, more and more patients have been identified with endoleaks. Five types of endoleaks have been defined. Endotension, or type V endoleak, remains controversial owing to its variable definition across studies and the range of proposed treatments. Thus, we performed a review of the reported studies to summarize the diagnosis and treatment of this rare complication after endovascular aneurysm repair to determine what we do and do not know about this rare form of endoleak. The presence of an endoleak places patients at an increased risk of aneurysm sac enlargement and potential rupture. Although additional research is essential and yet difficult to perform, we sought to provide a guide for the management of this perplexing endoleak known as endotension.

Post-EVAR Thrombus Density on Late Non-Contrast CT Scans Predicts Successful Aneurysm Exclusion

PURPOSE

The incidence of type II endoleaks (ELII) after endovascular aneurysm repair (EVAR) ranges from 10-44%. Aneurysm thrombus density after EVAR could predict successful aneurysm exclusion.

MATERIALS AND METHODS

Twenty-seven patients with an abdominal aortic aneurysm (AAA) who had a CT scan within the first 45 days (early group) post-surgery or after 7 months (late group) were included. Thrombus density was analyzed on non-contrast enhanced CT scans.

RESULTS

A total of 5/13 (38%) patients in the early group had an ELII and 9/14 (64.3%) in the late group had a persistent ELII since surgery. In the early group, thrombus density was similar in patients with or without an ELII (mean: 39.9 ± 4.8 vs. 41.9 ± 3.4, p = 0.7; median: 38.7 ± 4.8 vs. 39.7 ± 3.1, p = 0.8). In patients with an ELII, there was no difference in thrombus density at 45 days and after 7 months (mean: 39.9 ± 4.8 vs. 40.2 ± 2.1, p = 0.9; median: 38.7 ± 4.8 vs. 38 ± 2.6, p = 0.9). In patients without an ELII, thrombus density was significantly higher at 45 days than after 7 months (mean: 41.9 ± 3.44 vs. 25.7 ± 2.0, p = 0.005; median: 39.7 ± 3.11 vs. 24.4 ± 1.5, p = 0.004). In patients with an ELII, thrombus density was significantly higher after 7 months than in patients without an ELII (mean: 40.2 ± 2.1 vs. 25.7 ± 2.0. p = 0.001; median: 38 ± 2.6 vs. 24.4 ± 1.5, p = 0.003).

CONCLUSION

Low thrombus density after EVAR on late unenhanced CT scans predicts aneurysm exclusion.

Total realignment of multibranch stent graft using redo branch-in-branch endovascular repair for occult endoleak with rapid aneurysm sac expansion

Occult endoleaks can pose a diagnostic and treatment challenge. These endoleaks are not effectively identified by multiphase computed tomography angiography, magnetic resonance angiography, or contrast-enhanced ultrasound. Possible causes are small fabric tears and slow-flow, dynamic, or positional endoleaks. We describe a patient with rapid aneurysm sac expansion and disseminated intravascular coagulopathy 46 months after four-vessel branched physician-modified endograft repair of a ruptured extent III thoracoabdominal aneurysm. Imaging failed to demonstrate an endoleak but identified fresh blood products within the sac. The patient underwent total realignment using branch-in-branch repair with a physician-modified endograft. Repeated imaging 25 days postoperatively revealed decrease in aneurysm diameter by 10 mm.

Is Abdominal Aortic Aneurysm Behavior after Endovascular Repair Associated with Aneurysm Wall Density on Computed Tomography Angiography?

Background and objectives: Abdominal aortic aneurysm (AAA) growth is unpredictable after the endovascular aneurysm repair (EVAR). Continuing aortic wall degradation and weakening due to hypoxia may have a role in post-EVAR aneurysm sac growth. We aimed to assess the association of aortic wall density on computed tomography angiography (CTA) with aneurysm growth following EVAR. Materials and Methods: A total of 78 patients were included in the study. The control group consisted of 39 randomly assigned patients without aortic pathology. Post-EVAR aneurysm sac volumes on CTA were measured twice during the follow-up period to estimate aneurysm sac behavior. A maximum AAA sac diameter, aortic wall and lumen densities in Hounsfield units (HU) on CTA were measured. A relative aortic wall density (the ratio of aortic wall to lumen densities) was calculated. A statistical data analysis was performed using standard methods. Results: An increase in the AAA sac volume was observed in 12 (30.8%) cases. Median relative aortic wall density on CTA scores in both the patient and the control group at the level of the diaphragm were similar: 0.15 (interquartile range (IQR), 0.11–0.18) and 0.16 (IQR 0.11–0.18), p = 0.5378, respectively. The median (IQR) relative aortic wall density score at the level of the maximum AAA diameter in the patient group was lower than at the level below renal arteries in the control group: 0.10 (0.07–0.12) and 0.17 (0.12–0.23), p < 0.0001, respectively. The median (IQR) relative growing AAA sac wall density score was lower than a relative stable/shrinking AAA sac wall density score: 0.09 (0.06–0.10) and 0.11 (0.09–0.13), p = 0.0096, respectively. Conclusions: A lower aortic aneurysm wall density on CTA may be associated with AAA growth after EVAR.

Explant of aortic stent grafts following endovascular aneurysm repair

Background

Failure of endovascular aneurysm repair may require explant of the stent graft in a subset of patients. We sought to assess outcomes in a cohort of patients undergoing explant of endovascular aneurysm repair in both emergency and elective settings.

Methods

Patients undergoing explant of endovascular aneurysm repair were identified from a prospectively maintained database, with additional information obtained through retrospective analysis of medical records.

Results

Over a 21-year period, 1997–2018 (May), there were 597 endovascular aneurysm repair procedures performed in our institution for abdominal aortic aneurysm. There were 19 endovascular aneurysm repair explants; five of these were referrals from other vascular centres. The median age was 73 years (range 46–81). The median length of time from insertion to explant was 39.2 months (range 0–153). Indications for elective explant were type Ia endoleak (n = 4), type 1b endoleak (n = 1), type II endoleak with increasing sac size (n = 1), type I/III endoleak (n = 1), type IV endoleak (n = 1), and increasing sac size without evident endoleak (type V, n = 2). The remaining nine cases were emergency procedures, with four patients presenting with rupture post endovascular aneurysm repair, four patients presenting with acute stent thrombosis, of which one also had a type 1a endoleak and one aorto-enteric fistula. There were no mortalities in the elective group and three mortalities in the emergency group (0 vs 33.3%, p = 0.087). Overall 30-day mortality was 15.8%

Conclusion

Explant of aortic stent grafts can be associated with high mortality and morbidity rates, especially in the emergent setting. Patient and device selection and post-operative surveillance remain vitally important to optimise outcomes post endovascular aneurysm repair.

Association Between Perioperative Fibrinogen Levels and the Midterm Outcome in Patients Undergoing Elective Endovascular Repair of Abdominal Aortic Aneurysms

BACKGROUND

We investigated the potential association between perioperative fibrinogen levels and outcome in patients undergoing elective endovascular abdominal aneurysm repair (EVAR) of abdominal aortic aneurysms (AAAs).

METHODS

Consecutive patients with an intact AAA undergoing elective EVAR with a specific bifurcated endograft (Endurant, Medtronic) were recruited between December 2012 and October 2016. Preoperative and 24-hr postoperative fibrinogen levels were recorded, and potential associations with outcome were tested. Primary outcome measures included endoleaks, lower limb ischemic complications, including endograft limb occlusion, and aneurysm-related reinterventions.

RESULTS

Ninety-four patients (91 male, mean age 71.8 ± 8.0 years) with an intact AAA were enrolled in the study. The technical success was 98% (2 failures: 1 type Ia endoleak on completion angiography, 1 lower limb ischemia immediately postoperatively requiring femoral endarterectomy). There was 1 death during the first 30 days due to myocardial infarction (1%). Another patient died 15 months after the procedure from cardiac causes. During the existing follow-up (mean 14.8 ± 14.3 months), 14 patients (15%) developed an endoleak (4, type Ia endoleak and 10, type II endoleak), 6 patients (6.3%) had lower limb ischemia/endograft limb occlusion, and 10 patients (10.6%) required reintervention. Compared with the preoperative values, no significant change occurred with regard to the fibrinogen levels 24 hr after procedure (mean preoperative fibrinogen 360 ± 101 mg/dl vs 24-hr postoperative fibrinogen 349 ± 105 mg/dl, P = 0.1). Neither preoperative nor 24-hr postoperative fibrinogen levels were significantly associated with the development of endoleaks, lower limb ischemia, or reinterventions. However, the difference in fibrinogen levels (baseline to 24 hr after procedure) was significantly higher in patients with endoleaks (median -65 mg/dl vs. 15 mg/dl, P = 0.04).

CONCLUSIONS

Perioperative fibrinogen levels may play a role in predicting midterm outcomes in patients undergoing elective EVAR and appears to be associated, directly or indirectly, with the development of endoleaks. Further studies are needed to investigate these findings and explore future therapeutic implications.

Open Versus Endovascular Repair of Isolated Iliac Artery Aneurysms

PURPOSE:

Outcomes of open iliac artery repair (OIR) and endovascular iliac artery repair (EVIR) were compared at a tertiary referral vascular center.

METHODS:

From 2004 to 2015, all patients treated for isolated iliac artery aneurysms (IAAs) were retrospectively identified, and patient records and computed tomography (CT) scans were analyzed. The primary end point was overall survival; secondary end points were 30-day mortality and morbidity and freedom from reintervention. For follow-up, data from outpatient visits and CT scans following a standard surveillance protocol were used.

RESULTS:

A total of 106 IAAs in 94 patients were treated (mean follow-up: 35.7 months; 66 OIR; 40 EVIR). Six (15%) aneurysms from the EVIR group and 4 (6.1%) from open-operated IAA presented in the state of rupture. There was no difference in overall survival between EVIR and OIR ( P = .14). In multivariable analysis, higher risk of death was associated with ruptured IAA (rIAA; hazard ratio [HR]: 40.44, 95% confidence interval [CI]: 2.05-796.18; P = .02) and coronary heart disease (HR: 11.07, 95% CI: 1.94-63.36; P < .01). The 30-day mortality was 1.9% overall (0% OIR, 5.0% EVIR, P = .27), but there were no differences between OIR and EVIR in 30-day morbidity ( P = .11). Freedom from reintervention was higher for OIR than for EVIR ( P < .01). In multivariable analysis, a higher reintervention rate was seen in EVIR (HR: 10.80, 95% CI: 2.20-53.01; P < .01) and in rIAA (HR: 12.02, 95% CI: 1.31-111.11; P = .03).

CONCLUSION:

Iliac artery aneurysmss can be safely and effectively treated by EVIR or OIR regarding 30-day morbidity, mortality, and long-term survival, although freedom from reintervention is significantly lower after EVIR.

Determination of Endograft Apposition, Position, and Expansion in the Aortic Neck Predicts Type Ia Endoleak and Migration After Endovascular Aneurysm Repair

Purpose: To describe the added value of determining changes in position and apposition on computed tomography angiography (CTA) after endovascular aneurysm repair (EVAR) to detect early caudal displacement of the device and to prevent type Ia endoleak. Methods: Four groups of elective EVAR patients were selected from a dataset purposely enriched with type Ia endoleak and migration (>10 mm) cases. The groups included cases of late type Ia endoleak (n=36), migration (n=9), a type II endoleak (n=16), and controls without post-EVAR complications (n=37). Apposition of the endograft fabric with the aortic neck, shortest distance between the fabric and the renal arteries, expansion of the main body (or dilatation of the aorta in the infrarenal sealing zone), and tilt of the endograft toward the aortic axis were determined on the first postoperative and the last available CTA scan without type Ia endoleak or migration. Differences in these endograft dimensions were compared between the first vs last scan and among the 4 groups. Results: No significant differences in endograft configurations were observed among the groups on the first postoperative CTA scan. On the last CTA scan before a complication arose, the position of the fabric relative to the renal arteries, expansion of the main body, and apposition of the fabric with the aortic neck were significantly different between the type Ia endoleak (median follow-up 15 months) and migration groups (median follow-up 23 months) compared with the control group (median follow-up 19 months). Most endograft dimensions had changed significantly compared with the first postoperative CTA scan for all groups. Apposition had increased in the control group but had decreased significantly in the type Ia endoleak and migration groups. Conclusion: Progressive changes in dimensions of the endograft within the infrarenal neck could be detected on regular CTA scans before the complication became urgent in many patients.

Treatment options for isolated iliac artery aneurysms and their impact on aortic diameter after treatment

Purpose

Isolated iliac artery aneurysm (IIAA) is uncommon. It is frequently treated by endovascular aneurysm repair (EVAR). This study was to evaluate treatment results of IIAA and survey aortic diameter after EVAR.

Methods

Patients treated for IIAA in Seoul St. Mary's Hospital and Bundang Seoul National University from 2005 to April 2016 were retrospectively enrolled. The inclusion criteria of IIAA was >30 mm of iliac artery aneurysm without abdominal aortic aneurysm, which was treated by open surgical repair (OSR) or EVAR. Patients' clinical characteristics, treatment results, and mortality were obtained from electronic medical records. Diameters of aorta and iliac arteries were measured periodically with scheduled interval based on CT scans.

Results

Forty-nine patients (40 males; mean age, 71.9 ± 11.1 years) were enrolled. Five ruptured IIAAs were treated with EVAR (n = 1) or hybrid methods (n = 4). The diameter of ruptured IIAAs was 65 ± 31.4 mm, which was not significantly different from that of elective (44.3 ± 17.0 mm). Forty-four elective IIAA underwent 9 OSR, 31 EVARs, and 3 hybrid treatments (15 bifurcated and 12 straight stent-grafts). Treatment success rate was 93.8% without hospital mortality. There were 4 type I endoleak, 1 type II endoleak, and 1 type III endoleak without aneurysm-related mortality during follow-up. However, the aortic diameter was increased over time though there was no change or decrease in common iliac artery's diameter.

Conclusion

Treatment of IIAA included various endovascular modalities as well as open surgery. Regular surveillance is still needed due to aortic dilatation after its treatment.

Delayed migration of a thrombosed aortic endograft within a thrombosed aneurysm sac resulting in continued sac expansion and rupture

We present the case of delayed migration of a thrombosed aortic endograft within a thrombosed aneurysm sac that expanded and ruptured. Dilation of the aortic neck likely led to endograft migration and exposure of the occluded endograft and aneurysm sac to systemic pressure. Although no endoleak was identified, a key finding on ultrasound showed mobility of the sac thrombus. This may be an indicator of flow within the sac that may predict potential for rupture. Despite thrombosis of the aortic sac and endograft, the risk of rupture still lingers, and thus continued surveillance of occluded endografts may be prudent.

Systematic review of laparoscopic ligation of inferior mesenteric artery for the treatment of type II endoleak after endovascular aortic aneurysm repair

OBJECTIVE

Type II endoleak after endovascular aneurysm repair (EVAR) is frequently caused by persistent flow from the inferior mesenteric artery (IMA). The aim of this study was to assess the perioperative and midterm efficacy of laparoscopic ligation of the IMA for treatment of endoleak.

METHODS

MEDLINE, Cochrane Central Register of Controlled Trials, and Cochrane databases and key references were searched with Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology for studies reporting on laparoscopic ligation of the IMA for treatment of type II endoleak after EVAR.

RESULTS

Eight case studies and one study of a retrospective nature were identified. In total, 20 patients (18 men; mean age, 73.6 ± 2 years; with a mean abdominal aortic aneurysm diameter of 64.3 ± 10 mm) who underwent post-EVAR laparoscopic ligation of the IMA for type II endoleak were analyzed. The mean time from EVAR until intervention ranged from 6 to 18 months. All but one patient were asymptomatic; in 9, the aneurysm sac was enlarged, and in 11, the endoleak was considered persistent without sac enlargement. The mean procedural duration was 99 ± 24 minutes, with technical success rate of 90% (18/20); in two cases, the patients were successfully reoperated on laparoscopically in 24 hours. The mean hospitalization was 3.6 ± 1.2 days, with 0% (0/20) perioperative and 30-day mortality. No patient underwent open conversion or showed signs of intestinal ischemia. During follow-up of 32.6 ± 12 months, 13 of 20 patients had aneurysm sac regression, whereas the rest had a stable sac diameter without evidence of persistent type II endoleak.

CONCLUSIONS

Laparoscopic ligation of the IMA for treatment of type II endoleak after EVAR is a feasible and safe technique in specialized centers with high technical success rate and good midterm outcomes.

A Dedicated Surveillance Program Improves Compliance with Endovascular Aortic Aneurysm Repair Follow-up

BACKGROUND

Current recommendations suggest lifetime follow-up for endovascular aortic aneurysm repair (EVAR) patients to avoid consequences associated with endoleak and aneurysm enlargement. Follow-up compliance has been reported between 43% and 92%, with most single-center studies citing successful follow-up surveillance at less than 60%. We investigated follow-up completeness with a defined surveillance program and subsequent secondary intervention prevalence from a single center.

METHODS

Our surveillance program notified patients of the need for follow-up imaging and surgeon review. Data were obtained from retrospective review of a prospective database, including operative and follow-up details, follow-up imaging completeness, endoleak incidence, and secondary intervention prevalence.

RESULTS

Five hundred seventeen patients received elective EVAR from 2005 to 2015. Surveillance was achieved in 425 (82.3%). Mean number of follow-up studies was 4.2 ± 2.9 and median time to first follow-up was 36 days. Four hundred forty-eight patients (86.7%) had freedom from intervention. Sixty-nine unique patients (13.3%) had 107 secondary interventions. Median time to first secondary intervention in 69 patients was 476 days. Mean number of imaging studies for secondary intervention patients was 6.1 ± 3.9, compared with mean 3.4 ± 2.3 for patients without (P < 0.001). Overall mortality was 24.6% (n = 127), including 32 deaths of unknown cause (6.2% overall) and 95 of non-EVAR-related causes (18.3%). No aneurysm-related deaths were reported.

CONCLUSIONS

Regular post-EVAR surveillance through a dedicated program resulted in a high rate of follow-up compliance, 13.3% rate of secondary intervention, and low aneurysm-related mortality. Careful lifetime surveillance remains important in long-term care following elective EVAR.

Chronological Change of the Sac after Endovascular Aneurysm Repair

Purpose:

The purpose of this study was to evaluate the potential risk factors of type II endoleak and sac growth after endovascular aneurysm repair (EVAR) and the outcomes of secondary interventions.

Materials and Methods:

Ninety seven patients underwent elective EVAR for infrarenal abdominal aortic aneurysms in two tertiary centers between April 2005 and July 2013. Clinical and imaging parameters were compared among sac growth (>5 mm) and non-growth groups. Risk factors associated with sac growth and persistent type II endoleak were analyzed. The outcomes of reinterventions for persistent type II endoleak were determined.

Results:

Sac growth was observed in 20 cases (20.6%) and endoleak was found in 90% of them compared to 28.6% (22/77) in the non-growth group (P<0.001). The majority of endoleaks were type II (36/40) and 80.5% were persistent. Sac diameter, neck diameter and number of patent accessory arteries were also statistically significant for sac growth. On multivariate analysis, grade of calcification at the neck, grade of mural thrombus at the inferior mesenteric artery and number of patent accessory arteries were risk factors of persistent type II endoleak. Twenty six reinterventions were done for 16 patients with persistent type II endoleak, with a technical success rate of 88.5%, yet 55.5% showed sac growth regardless of technical success. There were no ruptures during the follow-up period.

Conclusion:

Sac growth after EVAR was mostly associated with persistent type II endoleak. Secondary interventions using transarterial embolization is partially effective in achieving clinical success.

Influence of endoleak positions on the pressure shielding ability of stent-graft after endovascular aneurysm repair (EVAR) of abdominal aortic aneurysm (AAA)

Background

Abdominal aortic aneurysm (AAA) is a kind of dangerous aortic vascular disease, which is characterized by abdominal aorta partial enlargement. At present, endovascular aneurysm repair (EVAR) is one of the main treatments of abdominal aortic aneurysm. However for some patients after EVAR the aneurysm re-expanded and even ruptured, leading to poor postoperative effect. The stent-graft endoleak after EVAR was realized to influence the AAA in-sac pressure and contribute to the aneurysm re-enlargement.

Methods

In order to analyze the influence of endoleaks positions on the pressure shielding ability of stent-graft after EVAR, type I and type III endoleak models were reconstructed based on computed tomography (CT) scan images, and the hemodynamic environment in AAA was numerically simulated.

Results

When the endoleak was at the proximal position the pressure shielding ability will be obviously weakened. While, the pressure shielding ability was higher in the systole phase than that in diastole phase when the endoleak located at the middle or distal positions. Unfortunately, when the endoleak located at the proximal position, the pressure shielding ability would be relatively weak in the whole cardiac cycle.

Conclusions

The results revealed that the influence of endoleaks on pressure shielding ability of stent-graft was both location and time specific.