Preoperative Inferior Mesenteric Artery Embolization: A Valid Method to Reduce the Rate of Type II Endoleak after EVAR?

Five-year follow-up of randomized clinical trial for pre-emptive inferior mesenteric artery embolization during endovascular aneurysm repair

OBJECTIVE

Type II endoleak (T2EL) is the most common type of endoleak after endovascular aneurysm repair (EVAR) and a common indication for reintervention due to late sac enlargement. Although pre-emptive embolization of the inferior mesenteric artery (IMA) has been proposed to prevent this, no studies have prospectively demonstrated its efficacy. This study aimed to prove the validity of IMA embolization during EVAR in selective cases by analyzing the mid-term outcomes of a randomized clinical trial (RCT).

METHODS

This single-center, parallel-group, non-blinded RCT included participants at high risk of T2EL, characterized by a patent IMA in conjunction with one or more following risk factors: a patent IMA ≥3 mm in diameter, lumbar arteries ≥2 mm in diameter, or an aortoiliac-type aneurysm. The participants were randomly assigned to two groups in a 1:1 ratio: one undergoing EVAR with IMA embolization and the other without. The primary endpoint was T2EL occurrence. The secondary endpoints included aneurysm sac changes and reintervention. In addition to RCT participants, outcomes of patients with low risk of T2EL were also analyzed.

RESULTS

The embolization and non-embolization groups each contained 53 patients. Five-year follow-up after the last patient enrollment revealed that T2ELs occurred in 28.3% and 54.7% of patients in the IMA embolization and non-embolization groups, respectively (P = .006). Both freedom from T2EL-related sac enlargement ≥5 mm and cumulative incidence of sac shrinkage ≥5 mm were significantly higher in the IMA embolization group than in the non-embolization group (95.5% vs 73.6% at 5 years; P = .021; 54.2% vs 33.6% at 5 years; P = .039, respectively). The freedom from T2EL-related sac enlargement ≥10 mm, an alternative indicator for T2EL-related reintervention, showed similar results (100% vs 90.4% at 5 years; P = .019). Outcomes in the low-risk group were preferable than those in the non-embolization group and comparable to those in the IMA embolization group.

CONCLUSIONS

A lower threshold for pre-emptive IMA embolization when implementing EVAR would be more appropriate if limited to patients at high risk of T2ELs.

Preemptive treatment of type II endoleak for abdominal aortic aneurysm with renal fusion (horseshoe kidney)

OBJECTIVE

To assess viability and safety of preemptive treatment of type II endoleak for abdominal aortic aneurysm (AAA) repairs.

METHODS

A 69-year-old man with renal fusion (horseshoe kidney) was referred for treatment of a 5.5 cm AAA. His anatomy was suitable for endovascular repair. The risk for type II endoleak was increased because of multiple infrarenal arterial orifices originating within the aneurysm sac. These included an accessory renal artery that supplied the renal isthmus, a patent inferior mesenteric artery, and a pair of large lumbar arteries originating from a single orifice (8 mm) at L3 spinal level. The lumbar orifice was selectively cannulated and occluded with thrombogenic coils 1 week prior to his endovascular aneurysm repair.

RESULTS

Aneurysm repair was uneventful with no signs of early or delayed endoleak and long-term follow-up of 5 years.

CONCLUSIONS

Preemptive coil embolization of perianeurysmal arteries may be considered as a safe and effective strategy for management of potential type II endoleak.

An Expert-Based Review on the Relevance and Management of Type 2 Endoleaks Following Endovascular Repair of Ruptured Abdominal Aortic Aneurysms

Ruptured abdominal aortic aneurysms (rAAAs) are life-threatening and require emergent surgical therapy. Endovascular aortic repair for rupture (rEVAR) has become the leading strategy due to its minimal invasive approach with expected lower morbidity and mortality, especially in patients presenting with hemodynamic instability and relevant comorbidities. Following rEVAR, intraoperative angiography or early postinterventional computed tomography angiography have to exclude early type 1 or 3 endoleaks requiring immediate reintervention. Persistent type 2 endoleaks (T2ELs) after rEVAR, in contrast to elective cases, can cause possibly lethal situations due to continuing extravascular blood loss through the remaining aortic aneurysm rupture site. Therefore, early identification of relevant persistent T2ELs associated with continuous bleeding and hemodynamic instability and immediate management is mandatory in the acute postoperative setting following rEVAR. Different techniques and concepts for the occlusion of T2ELs after rEVAR are available, and most of them are also used for relevant T2ELs after elective EVAR. In addition to various interventional embolization procedures for persistent T2ELs, some patients require open surgical occlusion of T2EL-feeding arteries, abdominal compartment decompression or direct surgical patch occlusion of the aneurysm rupture site after rEVAR. So far, in the acute situation of rAAAs, indications for preemptive or intraoperative T2EL embolization during rEVAR have not been established. In the long term, persistent T2ELs after rEVAR can lead to continuous aneurysm expansion with the possible development of secondary proximal type I endoleaks and an increased risk of re-rupture requiring regular follow-up and early consideration for reintervention. To date, only very few studies have investigated T2ELs after rEVAR or compared outcomes with those from elective EVAR regarding the special aspects of persisting T2ELs. This narrative review is intended to present the current knowledge on the incidence, natural history, relevance and strategies for T2EL management after rEVAR.

Understanding Type II Endoleak: A Harmless Imaging Finding or a Silent Threat?

Type II endoleak (T2EL) represents a challenging clinical entity following endovascular abdominal aortic aneurysm repair (EVAR). Although several studies have suggested that T2ELs are related to an increased risk of aneurysm sac growth and subsequent rupture, the exact role that T2ELs play in long-term outcomes remains debatable. Understanding the pathophysiology, diagnostic modalities, and management options of T2ELs is important for patients' safety and proper resource utilization. While conservative management may be suitable for asymptomatic patients with a stable aneurysm size, interventional approaches, including transarterial embolization, direct sac puncture embolization and open conversion have been described for patients with persistent T2EL associated with sac expansion. However, more research is needed to better determine the clinical benefit of such interventions. A thorough evaluation of all endoleak types before T2EL treatment would be reasonable for patients with T2ELs associated with sac expansion. Further studies are needed to refine treatment strategies aimed at minimizing T2EL-related complications. Collaborative efforts among vascular specialists, radiologists, and researchers are of paramount importance to address this ongoing clinical challenge.

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.

Safety of preoperative branch embolization in patients undergoing evar

The purpose of this systematic review is to evaluate the safety of pre-endovascular abdominal aortic aneurysm repair (EVAR) embolization of aortic side branches - the inferior mesenteric artery and lumbar arteries. Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines were followed. A search of MEDLINE and DIMENSION databases identified 9 studies published from 2011 to 2021 that satisfied the inclusion and exclusion criteria. These studies were analyzed to detect the incidence of embolization-related complications. A total of 482 patients underwent preoperative aortic side branch embolization, 30 (6.2%) of whom suffered some kind of minor complication. The only major complication observed was ischemic colitis in 4 (0.82%) patients, two (0.41%) of whom died after bowel resection surgery. Regarding these findings, aortic side branch embolization seems to be a safe procedure, with very low percentages of both minor and major complications.

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.

Inferior mesenteric artery revascularization can supplement salvage of mesenteric ischemia

The inferior mesenteric artery (IMA) has often been overlooked in favor of the celiac or superior mesenteric artery in arterial mesenteric ischemia, owing to the typically robust visceral collateral networks. In the present report, we have described a case series of patients in whom "salvage" revascularization of the IMA was performed after attempted celiac or superior mesenteric artery revascularization had been unsuccessful. The restored IMA inflow had resolved the symptoms for three patients. However, sole IMA revascularization was insufficient to reverse the course for two other patients with severe acute-on-chronic mesenteric ischemia. The IMA should be considered for salvage revascularization in the appropriate clinical scenario.

Patent iliolumbar artery increase no risk of type II endoleaks after endovascular abdominal aortic aneurysm: a case-control study

Objective

The aims of the present study were to explore the risk factors for type 2 endoleaks (T2ELs) after endovascular aneurysm repair (EVAR) and the association between T2ELs and the iliolumbar artery.

Materials and methods

A single-center, retrospective case-control study in West China Hospital was conducted among patients with infrarenal abdominal aortic aneurysm (AAA) who underwent EVAR between June 2010 and June 2019. The associations of patient characteristics, anatomical factors, internal iliac artery embolization, and ILA with the primary outcome were analyzed. The secondary objective was to analyze survival and reintervention between the T2EL group and the non-T2EL group. Kaplan-Meier survival, propensity matching analysis and multivariate logistic regression analysis were used.

Results

A total of 603 patients were included. The median follow-up was 51 months (range 5.0-106.0). There was a significant difference in the diameter of the lumbar artery (LA), middle sacral artery (MSA) and inferior mesentery artery (IMA), proportion of thrombus and LA numbers. The univariate analysis showed that T2ELs were more likely to develop more thrombus in aneurysm cavity (OR = 0.294, p = 0.012), larger MSA (OR = 1.284, p = 0.04), LA (OR = 1.520, p = 0.015), IMA (OR = 1.056, p < 0.001) and more LAs (OR = 1.390, p = 0.019). The multivariate analysis showed that the number of LAs (HR: 1.349, 95% CI: 1.140-1.595, p < .001) and the diameter of the IMA (HR: 1.328, 95% CI: 1.078-1.636, p = 0.008) were significantly associated with T2ELs. There were no new findings from the propensity score matching. The reintervention-free survival rates were significantly different between the two groups (p = 0.048). Overall survival and AAA-related death rates were not different between the two group. This was consistent with the PSM analysis.

Conclusion

The iliolumbar artery and the different internal iliac artery interventions may not increase the incidence of T2ELs. But the numbers of LAs and IMA diameter were independent risk factors for T2Els. T2ELs was associated with the reintervention but did not affect long-term survival or increase aneurysm-related mortality after EVAR.

High incidence of type 2 endoleak and low associated adverse events in the Vascular Quality Initiative linked to Medicare claims

INTRODUCTION

Type 2 endoleak (T2EL) is the most common adverse finding on postoperative surveillance after endovascular aortic aneurysm repair (EVAR). A low rate of aneurysm-related mortality with T2EL has been established. However, the optimal management strategy and the efficacy of reintervention remain controversial. This study used data from the Vascular Quality Initiative linked to Medicare claims (VQI-Medicare) to evaluate T2LE in a real-world cohort.

METHODS

This retrospective review of EVAR procedures in VQI-Medicare included patients undergoing their first EVAR procedure between 2015 and 2017. Patients with an endoleak other than T2EL on completion angiogram and those without VQI imaging follow-up were excluded. Patients without Medicare part A or part B enrollment at the time of the procedure or without 1-year complete Medicare follow-up data were also excluded. The exposure variable was T2EL, defined as any branch vessel flow detected within the first postoperative year. Outcomes of interest were mortality, reintervention, T2EL-related reintervention, post-EVAR imaging, and T2EL behavior including spontaneous resolution, aneurysm sac regression, and resolution after reintervention. The association of prophylactic branch vessel embolization (PBE) with T2EL resolution and aneurysm sac regression was also evaluated.

RESULTS

In a final cohort of 5534 patients, 1372 (24.7%) had an identified T2EL and 4162 (75.2%) did not. The median age of patients with and without T2EL was 77 and 75 years, respectively. There were no differences in mortality, imaging, reintervention, or T2EL-related reintervention at 3 years after the procedure for patients with T2EL. The aneurysm sac diameter decreased by 4 mm (range: 9-0 mm decrease) in the total cohort. Patients with inferior mesenteric artery-based T2EL had the smallest decrease in aneurysm diameter (median 1 mm decrease compared with 1.5 mm for accessory renal artery-based T2EL, 2 mm for multiple feeding vessel-based T2EL, and 4 mm for lumbar artery-based T2EL; P < .001). Spontaneous resolution occurred in 73.7% of patients (n = 809). T2ELs with evidence of multiple feeding vessels were associated with the lowest rate of spontaneous resolution (n = 51, 54.9%), compared with those with a single identified feeding vessel of inferior mesenteric artery (n = 99, 60.0%), lumbar artery (n = 655, 77.7%), or accessory renal artery (n = 31, 79.5%) (P < .001). PBE was performed in 84 patients. Patients who underwent PBE and were without detectable T2EL after EVAR had the greatest rate of sac regression at follow-up (7 mm decrease) compared with baseline.

CONCLUSIONS

T2EL after EVAR is associated with high rates of spontaneous resolution, low rates of aneurysm sac growth, and no evidence of increased early mortality or reintervention. PBE in conjunction with EVAR may be indicated in some circumstances.

Pre-Emptive Embolization of the Aneurysm Sac or Aortic Side Branches in Endovascular Aneurysm Repair: Meta-Analysis and Trial Sequential Analysis of Randomized Controlled Trials

BACKGROUND

To investigate outcomes of pre-emptive embolization of the aneurysm sac or aortic side branches in endovascular aneurysm repair (EVAR).

METHODS

The review was reported as per Preferred Reporting Items for Systematic reviews and Meta-Analyses 2020 with a preregistered protocol. Bibliographic sources (MEDLINE, Embase, and CENTRAL) were searched using subject headings and free text terms. Randomized controlled trials comparing EVAR with versus without embolization were included. Pooled estimates of dichotomous outcomes were calculated using odds ratio (OR) or risk difference (RD) and 95% confidence interval (CI) applying the Mantel-Haenszel method. Continuous outcomes were summarized using mean difference (MD) and 95% CI applying the inverse variance method. The certainty of evidence was appraised with the Grading of Recommendations Assessment, Development, and Evaluation framework. Version 2 of the Cochrane tool was used to assess the risk of bias. Trial sequential analysis assumed alpha = 5% and power = 80%.

RESULTS

Four randomized controlled trials were included. No significant difference was found in aneurysm-related mortality (RD 0.00, 95% CI -0.03 to 0.03), overall mortality (OR 1.85, 95% CI 0.42-8.13), aneurysm rupture (RD 0.00, 95% CI -0.03 to 0.03), type II endoleak-related reintervention (RD -0.07, 95% CI -0.21 to 0.06), procedure time (MD 20.12, 95% CI -11.54 to 51.77), or fluoroscopy time (MD 11.17, 95% CI -11.22 to 33.56). Patients with pre-emptive embolization had significantly lower odds of type II endoleak (OR 0.45, 95% CI 0.26-0.78) and sac expansion (OR 0.19, 95% CI 0.07-0.52). The risk of bias was high for all outcomes. The certainty of evidence was very low for all outcomes, except for type II endoleak, for which it was low. Trial sequential analysis showed an inconclusive result for overall mortality and type II endoleak-related reintervention but confirmed the advantage of embolization in reducing type II endoleak and sac expansion.

CONCLUSIONS

Limited, low certainty data suggest pre-emptive embolization confers no clinical benefits in EVAR.

Identifying Patients at High Risk for Post-EVAR Aneurysm Sac Growth

PURPOSE

Post-EVAR (endovascular aneurysm repair) aneurysm sac growth can be seen as therapy failure as it is a risk factor for post-EVAR aneurysm rupture. This study sought to identify preoperative patient predictors for developing post-EVAR aneurysm sac growth.

MATERIAL AND METHODS

A systematic review was conducted to select potential predictive preoperative factors for post-EVAR sac growth (including a total of 34.886 patients), which were evaluated by a retrospective single-center analysis of patients undergoing EVAR between 2009 and 2019 (N=247) with pre-EVAR computed tomography scans and at least 1 year follow-up. The primary study outcome was post-EVAR abdominal aortic aneurysm (AAA) sac enlargement (≥5 mm diameter increase). Multivariate Cox regression and Kaplan-Meier survival curves were constructed.

RESULTS

Potential correlative factors for post-EVAR sac growth included in the cohort analysis were age, sex, anticoagulants, antiplatelets, renal insufficiency, anemia, low thrombocyte count, pulmonary comorbidities, aneurysm diameter, neck diameter, neck angle, neck length, configuration of intraluminal thrombus, common iliac artery diameter, the number of patent lumbar arteries, and a patent inferior mesenteric artery. Multivariate analysis showed that infrarenal neck angulation (hazard ratio, 1.014; confidence interval (CI), 1.001-1.026; p=0.034) and the number of patent lumbar arteries (hazard ratio, 1.340; CI, 1.131-1.588; p<0.001) were associated with post-EVAR growth. Difference in estimated freedom from post-EVAR sac growth for patients with ≥4 patent lumbar arteries versus <4 patent lumbar arteries became clear after 2 years: 88.5% versus 100%, respectively (p<0.001). Of note, 31% of the patients (n=51) with ≥4 patent lumbar arteries (n=167) developed post-EVAR sac growth. In our cohort, the median maximum AAA diameter was 57 mm (interquartile range [IQR] = 54-62) and the median postoperative follow-up time was 54 months (IQR = 34-79). In all, 23% (n=57) of the patients suffered from post-EVAR growth. The median time for post-EVAR growth was 37 months (IQR = 24-63). In 46 of the 57 post-EVAR growth cases (81%), an endoleak was observed; 2.4% (n=6) of the patients suffered from post-EVAR rupture. The total mortality in the cohort was 24% (n=60); 4% (n=10) was AAA related.

CONCLUSIONS

This study showed that having 4 or more patent lumbar arteries is an important predictive factor for postoperative sac growth in patients undergoing EVAR.

CLINICAL IMPACT

This study strongly suggests that having 4 or more patent lumbar arteries should be included in preoperative counseling for EVAR, in conjunction to the instructions for use (IFU).

Routine Inferior Mesenteric Artery Embolisation is Unnecessary Before Endovascular Aneurysm Repair

OBJECTIVE

A type II endoleak is the most common complication during surveillance after endovascular aneurysm repair (EVAR), and a patent inferior mesenteric artery (IMA) is a known risk factor for an endoleak. The effect of routine IMA embolisation prior to EVAR on overall outcome is unknown. The aim of the study was to compare two strategies: routine attempted IMA embolisation prior to EVAR (strategy in centre A) and leaving the IMA untouched (strategy in centre B).

METHODS

Patients were treated with EVAR in two centres during the period 2005 - 2015, and the data were reviewed retrospectively. The primary endpoints were re-intervention rate due to type II endoleaks and the late IMA embolisation rate. Secondary endpoints included EVAR related re-intervention, sac enlargement, aneurysm rupture, and open conversion rates.

RESULTS

Strategy A was used to treat 395 patients. The IMA was patent in 268 (67.8%) patients, and embolisation was performed in 164 (41.5%). The corresponding figures for strategy B were 337 patients with 279 (82.8%) patent IMAs, two (0.6%) of which were embolised. The mean duration of follow up was 70 months for strategy A and 68.2 months for strategy B. The re-intervention rates due to a type II endoleak were 12.9% and 10.4%, respectively (p = .29), with no significant difference in the rate of re-interventions to occlude a patent IMA (2.0% and 4.7%, respectively; p = .039). The EVAR related re-intervention rate was similar, regardless of strategy (24.1% and 24.6%, respectively; p = .93). Significant sac enlargement was seen in 20.3% of cases treated with strategy A and in 19.6% treated with strategy B (p = .82). The rupture and conversion rates were 2.5% and 2.1% (p = .69) and 1.0% and 1.5% (p = .40), respectively.

CONCLUSION

The strategy of routinely embolising the IMA does not seem to yield any significant clinical benefit and should therefore be abandoned.

Preoperative predictive factors for type II endoleak: Trying to define high-risk patients

OBJECTIVE

Type 2 endoleaks (T2E) continue to be the "Achilles Heel" of endovascular aneurysm repair (EVAR). The aim of this study is to analyze preoperative factors of patients who underwent EVAR to define risk factors for T2E.

METHODS

From January 2015 to June 2020, 140 of 191 patients who underwent EVAR in our institution meet inclusion criteria for this study. Postoperative image control were performed using duplex ultrasound or CT scan. All T2E detected during follow-up were confirmed by angio CT. Preoperative anatomic and clinical variables were analyzed for T2E using t-test, Mann-Whitney U test and Fisher exact test. ROC curves and the corresponding area under the curve (AUC) were used to describe the predictive accuracy for endoleak.

RESULTS

T2E was detected in 16 patients (11.43%)0.12 of them (75%) were persistent and 10 (62.5%) provoked sac enlargement. Predictive factors for T2E were a greater IMA diameter (2.5 ± 0.5 vs. 3.3 ± 0.5, p < 0.001) and an increasing number of LA (4.8 ± 1.6 vs. 6.7 ± 1.4, p < 0.001). ROC curve analysis stablished thresholds of 3.5 mm for IMA diameter (sensitivity 77%, specificity 86%) and 5.5 for patent LA (sensitivity 88%, specificity 59%) as risk factor to develop T2E.

CONCLUSIONS

Preoperative aortic side branches embolization to avoid T2E is not still standarised. We tried to define a group of high-risk patients for T2E. According to our findings, patients with a preoperative IMA> 3 mm and more than 5 patent LA should be considered for pre-EVAR embolization.

An updated systematic review and meta-analysis of pre-emptive aortic side branch embolization to prevent type II endoleaks after EVAR

OBJECTIVE

Pre-emptive embolization of aortic side branches may be effective in preventing type II endoleaks (T2EL) based on a previous systematic review and meta-analysis by our group. Data up to 2019 was, however, only based on retrospective studies. The aim of the current study was to update the meta-analysis and evaluate the current evidence on this treatment strategy.

METHODS

A systematic literature search was performed with the same keywords and strategies used in the previous study. The complementary search included all articles published from January 1, 2019, through May 29, 2022. The incidence of aneurysm sac growth was the primary outcome of interest.

RESULTS

Four new studies were identified, including one randomized controlled study and one nationwide registry-based retrospective study. Overall, the incidence of sac size enlargement was 4.3% in the embolization group compared with 6.8% in the control group (odds ratio [OR], 0.38; 95% confidence interval [CI], 0.26-0.55), the incidence of T2EL was 19.7% vs 37.4% (OR, 0.38; 95% CI, 0.30-0.47), and the incidence of reintervention for T2EL was 1.2% vs 11.2% (OR, 0.12; 95% CI, 0.06-0.23).

CONCLUSIONS

Current evidence confirms lower incidence of aneurysm sac growth, T2EL, and reinterventions when pre-emptive embolization of aortic side branches is performed in conjunction with endovascular aneurysm repair, compared with no embolization. However, a higher level of evidence is still required to support a broad change of practice, including data on cost-effectiveness and on the potential effect on rupture.

Effectiveness of Inferior Mesenteric Artery Embolization on Type II Endoleak-Related Complications after Endovascular Aortic Repair (EVAR): Systematic Review and Meta-Analysis

Type II endoleak is one of the most common and problematic complications after endovascular aneurysm repair. It has been suggested that the inferior mesenteric artery (IMA) embolization could prevent further adverse events and postoperative complications. This article is a systematic review and meta-analysis following PRISMA guidelines. The Medline, PubMed, Embase, and Cochrane databases were used to identify studies that investigated the effect of IMA embolization on the occurrence of type II endoleaks and secondary interventions in a group of patients with abdominal aortic aneurysm who underwent EVAR compared with results after EVAR procedure without embolization. A random effects meta-analysis was performed. Of 3510 studies, 6 studies involving 659 patients were included. Meta-analysis of all studies showed that the rate of secondary interventions was smaller in patients with IMA embolization (OR, 0.17; SE, 0.45; 95% CI, 0.07 to 0.41; p < 0.01; I2 = 0%). The occurrence of type II endoleaks was also smaller in the embolization group (OR, 0.37; SE, 0.21; 95% CI, 0.25 to 0.57; p < 0.01; I2 = 16.20%). This meta-analysis suggests that IMA embolization correlates with lower rates of type II endoleaks and secondary interventions.

Five-year outcomes of the Bi- versus Trimodular EndurantTM stent-graft in 100 patients with infrarenal abdominal aortic repair

BACKGROUND

Recent studies on the Endurant™ endografts mainly compared outcomes of the bimodular stent-graft to other manufacturer's endografts or reported results for cases outside manufacturer's instructions for use (IFU), while data on the experience of standard endovascular aortic repair (EVAR) of infrarenal abdominal aortic aneurysms (AAA) inside manufacturer's IFU comparing the bi- with the trimodular device is limited.

METHODS

Inclusion criteria were: 1) infrarenal aneurysms (>50 mm diameter) treated by Endurant^TM II (END II) or Endurant^TM IIs (END IIs) stent-graft inside manufacturer's IFU; 2) available CTA with 1 mm reconstruction of the entire aorta prior to intervention. Endpoints comparing the devices included technical success, 30-day mortality, rate of complications (bleeding with conversion to open repair, stent-graft stenosis/occlusion, acute distal embolism, infection or postprocedural necessity of dialysis), endoleaks and reinterventions (5-year follow-up). Aneurysm sac diameters were compared between baseline preinterventional CTA and last post-interventional CTA.

RESULTS

One hundred patients (90% male, mean age 74 years) treated with END II (N.=66) or END IIs (N.=34) were included. Technical success was 99%. One procedure-related active bleeding occurred ending up in surgical conversion (END II N.=1). 30d mortality was 0%. No initial type I/III endoleaks were present. Re-interventions were required in 19/100 (19%) of patients (END II N.=10; END IIs N.=9, P=0.17). The outcome of EVAR including technical success, 30d mortality, rate of complications, endoleaks and re-interventions showed no significant differences comparing END II/IIs.

CONCLUSIONS

Five-year outcomes of EVAR show consistently safe and effective results for either END II or IIs device.

Endovascular Aortic Aneurysm Repair: A Narrative Review

Endovascular aortic aneurysm repair (EVAR) has evolved as minimally invasive method of treating infrarenal abdominal aortic aneurysms (AAA) with perioperatively mortality of less than 1% compared with 5% with open AAA repair as suggested by many randomized control trials. Computed tomography angiography is the imaging of choice for appropriate selection of a patient with EVAR. For patients with unsuitable anatomy, advanced EVARs techniques, such as fenestrated, branch, and chimney EVARs, are also increasingly being offered to patients with equal success. Patients with ruptured AAA are treated with this minimally invasive procedure. Percutaneous EVAR emerged with less of wound-related complications. Endoleaks are the most common complications peculiar to this procedure, and most are preventable by preoperative planning. They are detected on completion angiogram or on the surveillance imaging. This review discusses indications of EVAR, its selection criteria, procedural steps, and common complications associated with this procedure and advanced EVARs.

[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.

Incidence and Risk Factors for Sac Expansion after Endovascular Aneurysm Repair of Abdominal Aortic Aneurysms

Purpose

This study aimed to examine the sac changes after endovascular aneurysm repair (EVAR) in patients with abdominal aortic aneurysms.

Methods

Materials and We examined the aneurysm sac size initially and regularly after surgery in 157 consecutive patients who underwent EVAR in 2009-2019. Contrast-enhanced computed tomography (CT) scans were used as well as ultrasound images with non-enhanced CT scans in the patients with renal insufficiency. Sac expansion (SE) at 3 years was divided into two categories: progressive SE (PSE) defined as continuous sac enlargement of ≥5 mm on serial follow-up images at 1 and 3 years compared with the initial sac and delayed SE (DSE) defined as re-expansion of ≥5 mm compared with the regressed or stable sac at 1 year. The SE rate at 1 and 3 years and the risk factors for SE at 3 years were analyzed using logistic regression.

Results

During a median follow-up of 32.5 months, nine reinterventions in six patients were performed with open conversion (n=5) and endovascular repair (n=4). At 1 year, 112 patients underwent follow-up imaging. SE and sac regression were noted in 4 (3.6%) and 57 (50.9%) patients, respectively. Of the 64 patients with 3-year follow-up images, 16 (25%) exhibited SE (PSE [n=6] and DSE [n=10]). In the multivariable analysis, the risk factors for overall SE at 3 years were endoleaks at 1 year (P=0.006) and renal insufficiency (P=0.003).

Conclusion

During post-EVAR follow-up, patients with any endoleak at 1 year or renal insufficiency must be strictly monitored for SE development.

[The Prophylaxis of Type 2 Endoleaks is Relevant for Long Term Success of EVAR]

One out of 8 patients needs a reintervention after EVAR during the first 5 years. Two thirds of secondary interventions aim at treating endoleaks. The prevalence of complications doubles in the presence of endoleaks. Fourth generation stent grafts do not lead to a decrease in Type 2-associated reinterventions, but to better prevention of Type 1 and 3 endoleaks. Pretreatment of potential type 2 feeding arteries with embolising agents and treatment of the occurrence of type 2 endoleaks.

Outcomes of Preventive Embolization of the Inferior Mesenteric Artery during Endovascular Abdominal Aortic Aneurysm Repair

PURPOSE

To evaluate the impact of preemptive inferior mesenteric artery (IMA) embolization on outcomes of endovascular abdominal aortic aneurysm (AAA) repair (EVAR).

MATERIALS AND METHODS

From January 2015 to July 2017, all patients undergoing elective EVAR or fenestrated EVAR (F-EVAR) for asymptomatic AAA in a single tertiary hospital were retrospectively included. Three groups of patients were defined: patients with a patent IMA who underwent embolization during EVAR/F-EVAR (group 1), those with a patent IMA who did not undergo embolization during EVAR/F-EVAR (group 2), and those with a chronically occluded IMA (group 3). Preoperative aortic morphology, demographics, and procedural details were recorded. Aneurysmal growth (≥5 mm), reintervention, and overall mortality rates were analyzed using multivariate proportional hazard multivariate modeling. Propensity scores were constructed, and inverse probability weighting was applied to a new set of multivariate analyses to perform a sensitivity analysis.

RESULTS

A total of 266 patients (male, 95% [n = 249]) with a median age of 70 (65-77) years were included, with F-EVAR procedures comprising 87 (32.7%) of the interventions. There were 52, 142, and 72 patients in groups 1, 2, and 3, respectively. Changes in aneurysmal sac size did not differ between groups, nor did overall survival or reintervention rates at 24 months. IMA embolization was not identified as an independently protective factor for aneurysmal growth during follow-up (relative risk [RR] = 2.82/mm [0.96-8.28], P = .060), whereas accessory renal arteries (RR = 5.07/mm [1.72-14.96], P = .003) and a larger preoperative aneurysmal diameter (RR = 1.09/mm [1.03-1.15], P = .004) were independent risk factors for sac enlargement.

CONCLUSIONS

Preventive embolization of the IMA during EVAR or F-EVAR did not promote aneurysmal sac shrinking or decrease the reintervention rate at 2-year follow-up.

Prophylactic Aneurysm Embolization during EVAR Is Safe, Improves Sac Regression and Decreases the Incidence of Type II Endoleak

BACKGROUND

Clinically significant endoleaks remain costly, time-consuming, morbid and even mortal following endovascular aneurysm repair (EVAR). Perigraft arterial sac embolization (PASE) has been utilized to treat type II endoleaks (T2EL) diagnosed at the time of EVAR or after repair. Our objective was to analyze the safety and efficacy of prophylactic PASE on the incidence of T2EL and aneurysm sac regression in patients undergoing EVAR.

METHODS

We performed a retrospective review of prospectively maintained databases from the University of California San Diego and the San Diego Veterans Affairs hospitals between 2015 and 2019. Prophylactic PASE (pPASE) was performed at the time of EVAR with thrombin, contrast and gelfoam liquid embolic aneurysm treatment as previously described. We evaluated technical success, freedom from T2EL, freedom from reintervention, from sac expansion, from type I/III EL, from all-cause mortality (ACM), from aneurysm-related mortality and from non-target embolization (NTE).

RESULTS

A total of 44 patients were included in the study. Technical success was 100% and no NTE was observed. The average duration of follow-up was 14 ± 11months. In those treated and followed by CT scan, 100% of patients' aneurysms halted their growth following PASE, while 65.9% demonstrated sac regression. Mean aneurysm sac diameter decreased by 9 mm (95% CI 7-12). At 3 years, freedom from T2EL was 87.1%. Presence of T2EL did not result in aneurysm expansion during the follow-up period and thus did not require reintervention in any of these patients. Freedom from re-intervention was 83.2% for Type Ib EL and limb occlusion and all procedures were determined to be successful at the time of completion. No aneurysm-related deaths occurred during the follow-up.

CONCLUSIONS

PASE proves to be an effective tool in sac management for prophylaxis of endoleak and maximizing sac regression in EVAR. It is safe, effective and durable when employed in this manner in the short and medium-term and was associated with low rates of T2ELs and reinterventions and a 100% freedom from sac expansion. Further analysis is required to evaluate the long-term outcomes of this adjunctive procedure in EVAR.

Predictive Factor of the Possibility for Aortic Side Branches Coil Embolization during Endovascular Abdominal Aortic Aneurysm Repair

Objective: Coil embolization of aortic side branches has been additionally performed to prevent type II endoleak during EVAR in our institute. In this study, we evaluated the predictive factors of the possibility for coil embolization of the inferior mesenteric artery (IMA) and lumbar artery (LA) during EVAR.

Methods: Seventy-four EVAR patients during June 2015 and April 2019 were included in the study. The coil embolization procedural time for one vessel is limited to 10 min. Aortic side branches were selected with 4 Fr Shepherd hook type catheter (Medikit, Tokyo, Japan) and were embolized with Interlock (Boston Scientific, MA, USA) via microcatheter. As predictive factors, internal diameter of aortic side branches and the aortic diameter perpendicular to the origin of LA (aortic diameter) were evaluated.

Results: Coil embolization was tried for 52 patent IMAs and all IMAs except two IMAs with ostial stenosis were successfully coil embolized (96.2%). Totally 190 LAs were patent and coil embolization was tried for 144 LAs. Among 144 LAs, 106 LAs (73.6%) were successfully coil embolized and the diameter was significantly longer (2.30±0.51 mm vs. 2.04±0.41 mm, p=0.007) and aortic dimeter was significantly shorter (30.0±8.1 mm vs. 40.5±11.6 mm, p<0.001) in successfully embolized LAs. Cut off value of successful LA coil embolization was 2.06 mm for internal diameter and 36.1 mm for aortic diameter by receiver operating characteristic curve analysis. Successful coil embolization rate for LAs with internal diameter longer than 2.0 mm and aortic diameter less than 36.2 mm was 90% (72 among 80 LAs).

Conclusion: Coil embolization during EVAR for IMA was highly successful, if there was no calcified ostial stenosis. LA embolization was feasible especially for LAs with internal diameter ≥2.0 mm and aortic diameter ≤36.1 mm. This information would be useful to select the target vessel for aortic side branches coil embolization during EVAR. (This is a translation of Jpn J Vasc Surg 2019; 28: 389–396.)

Amplatzer Vascular Plug Embolization in Two Patients with Ruptured Infrarenal Aortic Aneurysm and Aortoiliac Occlusive Disease

Mortality for ruptured abdominal aortic aneurysm (AAA) is known to be high. When left untreated, it is nearly always fatal. Standard treatment options include open surgery and endovascular aneurysm repair (EVAR), but both techniques have limitations. Owing to comorbidities and anatomical constraints, some patients are deemed unsuitable for both open surgery and EVAR. In these patients, alternative treatment strategies can be of special interest. To our knowledge, these are the first two cases reported using an Amplatzer Vascular Plug II for aortic embolization in patients with coexisting aneurysmatic and aorto-bi-iliac occlusive disease requiring urgent treatment for contained AAA rupture. Successful aneurysm exclusion was noted at follow-up ranging from 5 months to 3 years, and no procedure-related complications occurred. We therefore believe that in selected patients, this could be an elegant alternative in life-threatening situations with sustained occlusion in the mid-term.

Multicentre randomised controlled trial to evaluate the efficacy of pre-emptive inferior mesenteric artery embolisation during endovascular aortic aneurysm repair on aneurysm sac change: protocol of Clarify IMA study

INTRODUCTION

Type II endoleak (EL) is frequently seen after endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA) and is often considered responsible for aneurysm sac enlargement if it persists. In order to reduce type II EL and consequent sac enlargement, pre-emptive embolisation of the inferior mesenteric artery (IMA), which is a main source for persistent type II EL, has been introduced in many vascular centres. At present, there is a lack of robust evidence to support the efficacy of pre-emptive embolisation of IMA on reduction of persistent type II EL with subsequent sac shrinkage.

METHOD AND ANALYSIS

This multicentre, randomised controlled trial will recruit 200 patients who have fusiform AAA ≥50 mm/rapidly enlarging fusiform AAA, with patent IMA, and randomly allocate them either to a pre-emptive IMA embolisation group or non-embolisation control group in a ratio of 1:1. The primary endpoint is the difference of aneurysm sac volume change assessed by CT scans between the pre-emptive IMA embolisation group and the control group at 12 months after EVAR. The secondary endpoints are defined as change of aneurysm sac volume in both groups at 6 and 24 months, freedom from sac enlargement at 12 and 24 months after EVAR, prevalence of type II EL at 1, 6, 12 and 24 months evaluated by contrast-enhanced CT, reintervention rate, aneurysm related mortality, overall survival, perioperative morbidity, volume of contrast media used during EVAR and dosage of radiation.

ETHICS AND DISSEMINATION

The protocol has been reviewed and approved by the ethics committee of Nara Medical University (No. 2113). The findings of this study will be communicated to healthcare professionals, participants and the public through peer-reviewed publications, scientific conferences and the University Hospital Medical Information Network Clinical Trials Registry home page.

TRIAL REGISTRATION NUMBER

UMIN000035502.

Laparoscopic Clipping of the Inferior Mesenteric Artery and Intraoperative Indocyanine Green Angiography for Type II Endoleak Following Endovascular Aneurysm Repair

Background: Type II endoleaks from a patent inferior mesenteric artery (IMA) occur in up to one-third of patients undergoing endovascular repair of abdominal aortic aneurysms. In the majority of patients, retrograde flow in the aneurysmal sac outside the endograft will seal over time and is rarely associated with sac enlargement or aortic rupture. Intervention is generally recommended in patients with progressively enlarging endoleaks, especially when the sac diameter increases >10 mm during the follow-up, and endovascular IMA embolization has a high rate of treatment failure. Methods: We report a procedure of laparoscopic IMA clipping combined with intraoperative indocyanine green (ICG) angiography to confirm vascular anatomy, colonic perfusion, and the technical success of the procedure. Results: Three selected octogenarian patients with persistent type II endoleak after endovascular repair of abdominal aortic aneurysm underwent IMA clipping with ICG angiography. Mean operative time was 58 ± 9 minutes. There were no procedure-related complications, and no hypersensitivity reactions nor other side effects associated with ICG dye administration occurred. All patients were discharged home on postoperative day 1 and are asymptomatic and free of recurrence at a mean follow-up of 15 months. Conclusions: Laparoscopic IMA clipping is a safe remedial procedure in patients with type II endoleak after endovascular repair of abdominal aortic aneurysms.

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

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

Sac Embolization and Side Branch Embolization for Preventing Type II Endoleaks After Endovascular Aneurysm Repair: A Meta-analysis

Purpose:To investigate the efficacy and safety of preoperative side branch embolization or intraoperative sac embolization for preventing type II endoleaks after endovascular aneurysm repair (EVAR). Materials and Methods: A systematic literature search of MEDLINE and EMBASE was performed to identify studies that evaluated the outcomes of sac embolization vs no embolization or side branch embolization vs no embolization in patients who received EVAR. Among the 904 studies screened, 17 studies with 2084 participants were included in this review. Outcome measures included the type II endoleak rate, the reintervention rate for type II endoleaks, the incidence of types I/III endoleaks, and the rate of complications. Fixed (no heterogeneity) or random effects models were constructed for each outcome; the results are presented as the odds ratio (OR) with 95% confidence interval (CI). Results: The sac embolization group had significantly lower type II endoleak (OR 0.21, 95% CI 0.13 to 0.34, p<0.001) and reintervention (OR 0.15, 95% CI 0.07 to 0.33, p<0.001) rates than the no embolization group. No significant differences between the 2 groups were found for the type I/III endoleak rate (OR 0.57, 95% CI 0.23 to 1.37, p=0.21) or complication rate (OR 1.22, 95% CI 0.32 to 4.70, p=0.77). Compared with no embolization, side branch embolization was also associated with a decrease in type II endoleak (OR 0.35, 95% CI 0.21 to 0.60, p<0.001) and reinterventions (OR 0.10, 95% CI 0.04 to 0.27, p<0.001). One severe procedure-related complication (fatal colon ischemia) was reported in the side branch embolization group. Conclusion: Sac embolization and side branch embolization are safe and effective in preventing type II endoleaks. Further randomized trials are needed to directly compare the clinical outcomes of these procedures.

Techniques and future perspectives for the prevention and treatment of endoleaks after endovascular repair of abdominal aortic aneurysms

The presence of endoleaks remains one of the main drawbacks of endovascular repair of abdominal aortic aneurysms leading to the increase of the size of the aneurysmal sac and in most of the cases to repeated interventions. A variety of devices and percutaneous techniques have been developed so far to prevent and treat this phenomenon, including sealing of the aneurysmal sac, endovascular embolisation, and direct sac puncture. The aim of this review is to analyse the indications, the effectiveness, and the future perspectives for the prevention and treatment of endoleaks after endovascular repair of abdominal aortic aneurysms.

Preoperative Inferior Mesenteric Artery Embolization is a Cost-effective Technique that May Reduce the Rate of Aneurysm Sac Diameter Enlargement and Reintervention After EVAR

BACKGROUND

Type II endoleaks are the most common complications after endovascular repair of abdominal aortic aneurysms (EVARs). Some studies have shown the benefit of preventive inferior mesenteric artery (IMA) embolization, but its efficacy and cost-effectiveness continue to be controversial. The aim of this study was to evaluate the efficacy of this procedure on the increase in aneurysmal sac diameter during follow-up.

MATERIALS AND METHODS

All consecutive patients who underwent the embolization of the IMA before EVAR in our center, between January 2014 and July 2016, were included. We retrospectively compared the diameter of the aortic aneurysm sac, the rate of endoleak and reinterventions, and the theoretical cost of management between these patients (group 2) and a historical cohort of patients treated for EVAR before January 2014 who did not undergo prior IMA embolization (group 1).

RESULTS

Two hundred twenty-four patients were retrospectively analyzed. After exclusion, we compared a group of 37 embolized patients with a control group of 46 patients. The rate of enlargement in the aneurysmal sac diameter was significantly higher in the control group at 2 years (27.9% vs. 4.3%, P = 0.025). The type II endoleak rate at 2 years was significantly higher in the control group (53.1% vs. 18.2%, P = 0.012), as was the aneurysm-related reintervention rate (31.1% vs. 8.1%, P = 0.013). Multivariate analysis confirmed these results. At 2 years of follow-up, there was no difference in the overall cost of patient management between the 2 groups.

CONCLUSIONS

Preventive IMA embolization is an effective, reliable, and cost-effective technique that seems to reduce the rate of the aneurysmal sac diameter enlargement, type II endoleak, and reinterventions after EVAR.

Type II Endoleak After Endovascular Aortic Aneurysm Repair Using the Endurant Stent Graft System for Abdominal Aortic Aneurysm with Occluded Inferior Mesenteric Artery

PURPOSE

To evaluate the incidence of type II endoleak (EL-II) and aneurysm enlargement after endovascular aneurysm repair (EVAR) using the Endurant stent graft in patients with abdominal aortic aneurysm (AAA) with occluded inferior mesenteric artery (IMA).

MATERIALS AND METHODS

Between 2012 and 2017, 103 patients who underwent EVAR using the Endurant stent graft for AAA with occluded IMA (50 patients with prophylactic embolized IMA and 53 with spontaneous occluded IMA) were retrospectively reviewed. The incidence of EL-II and aneurysm enlargement was evaluated. Predictive factors for persistent EL-II were evaluated based on patient characteristics, preprocedural anatomical characteristics, intraprocedural details, and postprocedural complications.

RESULTS

Incidence rates of early EL-II and persistent EL-II were 6.8% (7/103 patients) and 4.9% (5/103 patients), respectively. Aneurysm enlargement was found in 10 patients (9.7%), including all 5 patients with persistent EL-II, 3 with de novo EL-II, and 2 with no EL-II. The rates of freedom from aneurysm enlargement at 1, 2, and 3 years were 98.7%, 97.0%, and 93.1% for the group without persistent EL-II, and 80.0%, 60.0%, and 20.0% for the group with persistent EL-II (p < 0.001), respectively. The maximum aneurysm diameter (odds ratio (OR), 1.16; 95% confidence interval (CI), 1.01-1.34; p = 0.0362) and the number of patent lumbar arteries (OR, 2.72; 95% CI, 1.07-6.90; p = 0.0357) were predictive of persistent EL-II.

CONCLUSIONS

The incidence of EL-II after EVAR using the Endurant stent graft for AAA with occluded IMA was low, but most early EL-II persisted and resulted in aneurysm enlargement. Level of Evidence Level 4, Case Series.

Laparoscopic ligation of Type II endoleaks following endovascular aneurysm repair: A systematic review

INTRODUCTION

The clinical significance of Type II endoleak remains contentious; the strategies used for its management have continued to expand. We systematically review the literature and comprehensively appraise the effectiveness of laparoscopic intervention in the management of this common complication.

METHODS

A systematic search was performed in accordance to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines on MEDLINE, EMBASE and Cochrane Library for relevant articles reporting laparoscopic surgery of Type II endoleak post-endovascular aortic repair.

RESULTS

Thirteen studies representing 40 patients were investigated. Mean age was 72.7 years, and proportion of males was 90.0%. All patients were American Society of Anesthesiologists grade II and above and underwent standard infrarenal endovascular aneurysm repair. The mean duration of operation was 130.2 min, with a mean blood loss across of 173.8 mL. The overall technical success rate was 90% (27/30). Two patients required reoperation within 24 h, with further lumbar ligations that were successful. One other patient required conversion to open surgery due to significant bleeding at the dorsal aorta. The perioperative and 30-day mortality rate was 2.5% (1/40). The mean length of hospital stay was 3.7 days (range 1 to 10 days). The mean length of follow-up was 36.7 months (range 3 to 103.2 months), where the rate of recurrence was 22.5% (9/40).

CONCLUSIONS

Laparoscopic ligation of feeding vessels causing Type II endoleak is potentially an alternative treatment after failed standard endovascular embolization, particularly in select centres with necessary resources and capabilities.

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.

Repair of abdominal aortic aneurysms: preoperative imaging and evaluation

Imaging is a critical component of the pre-procedure evaluation and planning of endovascular aneurysm repair (EVAR). Imaging is the mainstay for proper assessment of procedural candidacy, relevant vascular anatomy, device selection, and surgical approach. Computed tomography angiography (CTA) has long been considered the preferred modality for pre-operative imaging and evaluation prior to EVAR. Recently, advances in image quality and software technology have further enhanced the proceduralist's ability to plan and perform EVAR. In this review, we highlight the current state of the art to provide interventionalists a contemporary assessment of the available tools for pre-operative imaging and evaluation prior to EVAR.

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.