Endoleaks In Patients Research Articles

Evaluating the feasibility of contrast-enhanced ultrasound for detecting after preemptive coiling endoleaks in endovascular aortic aneurysm repair: A pilot study

Endovascular aortic aneurysm repair is widely used for the treatment of abdominal aortic aneurysm (AAA), but has a 10% to 40% incidence of type II endoleak during follow-up. There are various techniques to treat these endoleaks in the case of enlarging of the AAA, but the clinical effectiveness is low. In recent years, preemptive AAA sac embolization has shown some encouraging results with significant AAA shrinkage. However, the presence of embolic material can complicate continued endoleak detection making assessment of treatment outcome difficult. We investigate the ability of contrast-enhanced-ultrasound examination to detect endoleaks in patients undergoing preemptive coil embolization of the AAA sac.

Side branch embolization before endovascular abdominal aortic aneurysm repair to prevent type II endoleak: A prospective multicenter study

PurposeThe purpose of the study was to evaluate the efficacy and safety of pre-emptive transcatheter arterial embolization (P-TAE) of aortic side branches to prevent type II endoleak in patients with abdominal aortic aneurysm after endovascular abdominal aneurysm repair (EVAR). Materials and methodsThis multicenter, prospective, single-arm trial enrolled 100 patients with abdominal aortic aneurysm from nine hospitals between 2018 and 2021. There were 85 men and 15 women, with a mean age of 79.6 ± 6.0 (standard deviation) years (range: 65–97 years). P-TAE was attempted for patent aortic side branches, including the inferior mesenteric artery, lumbar arteries, and other branches. The primary endpoint was late type II endoleak incidence at 6 months post-repair. Secondary endpoints included changes in aneurysmal sac diameter at 6- and 12 months, complications, re-intervention, and aneurysm-related mortality. Aneurysm sac changes at 6- and 12 months was compared between the late and no-late type II endoleak groups. ResultsCoil embolization was successful in 80.9% (321/397) of patent aortic side branches, including 86.3% of the inferior mesenteric arteries, 80.3% of lumbar arteries, and 55.6% of other branches without severe adverse events. Late type II endoleak incidence at 6 months was 8.9% (8/90; 95% confidence interval: 3.9–16.8%). Aneurysm sac shrinkage > 5 mm was observed in 41.1% (37/90) and 55.3% (47/85) of the patients at 6- and 12-months post-EVAR, respectively. Patients with late type II endoleak had less aneurysm sac shrinkage than those without type II endoleak at 12 months (˗0.2 mm vs. ˗6.0 mm; P = 0.040). No patients required re-intervention for type II endoleak, and no aneurysm-related mortalities occurred. ConclusionP-TAE is safe and effective in preventing type II endoleak, leading to early sac shrinkage at 12 months following EVAR.

Assessing the diagnostic accuracy of artificial intelligence in post-endovascular aneurysm repair endoleak detection using dual-energy computed tomography angiography.

The aim of this study was to evaluate the diagnostic accuracy of an artificial intelligence (AI) tool in detecting endoleaks in patients undergoing endovascular aneurysm repair (EVAR) using dual-energy computed tomography angiography (CTA). The study involved 95 patients who underwent EVAR and subsequent CTA follow-up. Dualenergy scans were performed, and images were reconstructed as linearly blended (LB) and 40 keV virtual monoenergetic (VMI) images. The AI tool PRAEVAorta®2 was used to assess arterial phase images for endoleaks. Two experienced readers independently evaluated the same images, and their consensus served as the reference standard. Key metrics, including accuracy, precision, recall, F1 score, and area under the receiver operating characteristic (ROC) curve (AUC), were calculated. The final analysis included 94 patients. The AI tool demonstrated an accuracy of 78.7%, precision of 67.6%, recall of 10 71.9%, F1 score of 69.7%, and an AUC of 0.77 using LB images. However, the tool failed to process 40 keV VMI images correctly, limiting further analysis of these datasets. The AI tool showed moderate diagnostic accuracy in detecting endoleaks using LB images but failed to achieve the reliability needed for clinical use due to the significant number of misdiagnoses.

Experience in Treatment of Patients with First Type Secondary Endoleaks

INTRODUCTION: First type secondary endoleaks (EL) require quickest elimination, primarily using the endovascular methods. Despite the existence of a sufficiently large number of methods of their elimination, the results of treatment remain ambiguous.
 AIM: Analysis of our own experience of elimination of the first type ELs in patients after endoprosthetics of infrarenal abdominal aortic aneurysm.
 MATERIALS AND METHODS: The study is retrospective with prospective observation. All patients underwent computed tomography (CT) for identification of the type of EL and choosing a method of its elimination. The term first type secondary EL was understood as EL which developed in the long-term period after the primarily negative CT-angiography after endoprosthetic repair of the aorta.
 RESULTS: ELs of Ia type were diagnosed in 14 cases, in one case EL of Ib type was identified. On average, first type secondary ELs were identified in 34 months after the primary operation for endograft implantation. In 2 of 15 patients, EL were symptomatic. The elimination of the first type EL required an individualized approach in all cases. The main methods of elimination of the first type EL were: elongation using Jotec E-iliac (n = 1); coiling with implantation of Gore cuff and Chimney-stenting of the left renal artery (LRA; n = 2); implantation of Gore cuff (n = 4); reinforcement with Aptus EndoAnchors (n = 2); Cuff Gore implantation and LRA stenting by Chimney-technique (n = 1); implantation of Cuff Jotec and reinforcement with Aptus EndoAnchors (n = 1); aneurysmal sac coiling (n = 2); Gore cuff implantation with fixation with EndoAnchors and LRA stenting using Chimney-technique (n = 1). The technical success of EL elimination was 100% (in all cases, the success was confirmed by intraoperative angiography, as well as by CT angiography or ultrasound duplex scanning with contrast enhancement after surgery), there were no deaths. In the long-term period (from 6 to 60 months), re-interventions were performed in two cases, fatal outcome happened in one case, after a late open conversion for elimination of EL.
 CONCLUSION: In 13% of cases, first type ELs were symptomatic, and their elimination required individual approach with taking into account anatomical factors and the implanted graft. The medium-term results of the elimination of the first type EL are good, no fatal cases have been reported, and the number of reinterventions has reached 20%, which requires monitoring in the postoperative period.

Predictive Parameters of Type 1A Endoleak for Elective Endovascular Aortic Repair: A Single-Center Experience

One of the most important factors that affects the success of Endovascular Aortic Repair (EVAR) treatment is the morphology of the neck of the aneurysm. Today, EVAR can be performed even in patients who do not meet the Instruction For Use criteria with hostile neck risk factors; thanks to the developing experience and technology. Our aim in this study was to determine risk factors for Type 1a endoleaks in patients who underwent EVAR and predictive factors for Type 1a endoleaks in patients with combinations of these risk factors. Patients who underwent elective EVAR for infrarenal abdominal aortic aneurysm in our medical center between July 2016 and January 2021 were enrolled. Of these 244 patients, 180 patients with documented preoperative and postoperative computed tomographic angiography results and a follow-up of at least 1year were included in the study. The Mann-Whitney U test and Student's t-test were used to assess the relationship between nominal data and numerical values, and the t-test and Wilcoxon test were used to compare dependent groups. Logistic regression analysis was performed to model risk factors associated with endoleaks. The results showed that a neck length less than 15mm increased the development of type 1a endoleak by 10.4 times (P<0.001). Furthermore, a neck diameter more than 28mm increased the development of type 1a endoleak by 21.9 times (P=0.04). A conical neck structure (gradual neck dilation > 2mm) increased the development of type 1a endoleaks 4.8 times (P=0.04). The presence of calcification (> 150 Hounsfield Unit and > 2mm) in the neck increased the risk of type 1a endoleaks fourfold (P=0.04). Hostile neck parameters were analyzed and patients with only 1 parameter (n=69) had a 7.2% type 1a endoleak rate, while patients with 2 parameters (n=15) had 26.6% and patients with more than 2 parameters (n=11) had 45.5% type 1a endoleak rate. Morphologic features of the neck structure of the aneurysm are among the most important parameters that affect the success of EVAR treatment. Alternative treatments should be considered in patients with more than 1 unfavorable neck parameter.

Raised BMI is associated with fewer Type I endoleaks in patients treated with the Gore Excluder device: data from the Global Registry for Endovascular Aortic Treatment (GREAT).

Obesity is increasing in prevalence globally and within the cohort of vascular surgical patients, leading to poorer outcomes. There are few data on endoleak as a complication of AAA surgery in obese patients. The aim of this study was to use large scale registry data from the Global Registry for Endovascular Aortic Treatment (GREAT) to interrogate any relationship between obesity and endoleak following endovascular aneurysm repair (EVAR) using a Gore Excluder device (W. L. Gore & Associates, Newark, DE, USA), in order to guide treatment recommendations in the future. A retrospective review of the GREAT Registry was carried out and patients who were recorded as having a postoperative endoleak requiring intervention were included. Patient demographics including Body Mass Index (BMI), aneurysm parameters and on- or off-instructions for use (IFU) were recorded. Ruptured AAA were excluded. Data were obtained for 3326 patients with an operation date between August 25, 2010 and September 22, 2019. Obese patients were significantly less likely to have a Type 1 endoleak (Fisher's Exact P value=0.006), and the association was maintained in a multiple logistic regression model which controlled for age, gender, neck angulation and off IFU device use (OR=0.33, P=0.01). Among AAA patients treated with a Gore Excluder device (W. L. Gore & Associates), a higher BMI category was associated with a lower risk of Type 1 endoleak requiring reintervention. Further work needs to be carried out to assess our findings in other patient cohorts.

Sac Behavior Serves as a Strong Prognosticator for Development of Late Endoleak in Patients Without Early Endoleak

Sac Behavior Serves as a Strong Prognosticator for Development of Late Endoleak in Patients Without Early Endoleak

A Novel Technique and Outcomes for Transcaval Endoleak Embolization

Strategies for embolization of type 2 endoleaks include translumbar, transgraft, transarterial, and transcaval approaches. The transcaval approach is limited by an inconsistent ability to access the aortic sac and the risk of puncturing and damaging the endograft or adjacent structures. We describe a novel technique for caval to aortic aneurysm sac access and report early outcomes. A retrospective review of all patients who underwent transcaval embolization (TCE) at a tertiary referral center. From March 2019 to June 2021, 12 patients were identified to have undergone a novel approach to transcaval aortic sac access using a 0.014″ heavy weight tip wire guide and continuous current electrocautery to create the connection between the inferior vena cava and aortic aneurysm sac. The endoleak outflow vessel is then selectively embolized with coils or liquid embolic agents. When selective embolization was not possible, the aneurysm sac was instilled with liquid embolic agents to induce thrombosis. Twelve patients underwent transcaval embolization using this method over the 3-year period. The average patient age was 79.2±6.2years and 10/12 (83.3%) were male. A high rate of comorbidities was noted in the cohort. Transcaval access into the aortic sac was achieved in all patients, while selective cannulation of outflow vessels was accomplished in 2/12 (16%) target vessels. Of these, both cases had vessels embolized using detachable coils and liquid embolic agents. Nonselective embolization was performed using liquid embolic and thrombotic agents in the other 10/12 cases. There was one perioperative complication of minor bleeding (1/12, 8.3%). Two patients were observed in intensive care unit for back pain. A persistent endoleak was identified on postoperative imaging performed at 30days in 4/12 (33.3%) patients. Sac enlargement > 5mm following TCE was observed in 3/12 (25%) patients. Three patients underwent open conversion with endovascular aneurysm repair explant. One patient was explanted at 1month after failure to embolize the endoleak flow channel using TCE. A second was explanted for persistent endoleak found to be a Type IIIb with aortic diameter growth > 5mm at 15-month follow-up. The third explant was performed for aortic sac infection at 4months postprocedure without endoleak. TCE is an adjunctive technique to treat endoleaks in patients who have either failed transarterial or translumbar access. An electrified 0.014″ chronic total occlusion wire technique for transcaval access to the aortic sac for endoleak embolization can be successful in all cases without significant acute morbidity or mortality. The transcaval approach is still limited by ability to steer catheters and microcatheters into the outflow vessels with a resultant persistent endoleak and eventual need for explant.

Frequency of endoleaks after endovascular treatment of abdominal aortic aneurysm

Nowadays, there are more and more advantages of endovascular treatments for aneurysms of the abdominal aorta compared to open surgical treatment. Endovascular procedure is less invasive and the mortality rate is significantly lower in contrast to open surgical treatment. One of the complications of endovascular treatment of abdominal aortic aneurysm is the occurrence of permeability or endoleak. In this paper, we investigated the frequency and characteristics of endoleaks in patients treated endovascularly for the abdominal aortic aneurysm. Work methods are based on statistical data processing of 60 patients who were treated at the Clinical Department for diagnostic and interventional radiology, University Hospital Split. The data is collected from the archives of the mentioned clinical institute from patients who were treated in the period from January 2016 to May 2019. The analysis revealed that endoleak appeared in 63% of patients. The most common type of endoleak that occurred was endoleak type II. Reintervention related to endoleak was required in 4 patients. In most patients, endoleak type II gradually receded and did not require re-intervention. The average follow-up time of the patients analyzed in this study was 26 months. The average number of controls was 4. Endovascular treatment is a newer method of treatment and constant monitoring of the implanted stent-graft is required.

Preoperative high lymphocyte-to-monocyte ratio is associated with intraoperative type I endoleak in patients with TAA with TEVAR.

Various inflammatory factors are closely associated with the incidence of thoracic aortic aneurysms (TAAs). Furthermore, the severity of inflammation is closely related to the absolute value and proportion of each leukocyte subgroup. Only few reports have analyzed the importance of lymphocyte-monocyte ratio (LMR) as a potential inflammatory marker in vascular diseases. Therefore, we aimed to investigate the effect of peripheral blood LMR on thoracic endovascular aortic repair (TEVAR) in patients with TAA. A retrospective study of the clinical data collected in our hospital between January 2016 and January 2021 was performed on 162 patients with TAA treated with TEVAR, based on the inclusion and exclusion criteria for patient selection. Based on whether the patient had the clinical symptoms at admission and the occurrence of type I endoleaks during operation, patients were divided into two groups, respectively: an intraoperative type I endoleak group (n = 34) and a group without intraoperative type I endoleak (n = 128), and a group with clinical symptoms (n = 31) and a group without clinical symptoms (n = 131). The clinical data of these two groups were compared, the free from second intervention rates related to endoleak and the preoperatively LMR of the two groups was calculated. LMR was calculated preoperatively. Receiver-operating characteristic curve analysis was used to determine the cut-off for preoperative LMR values. Based on the cut-off point, patients were divided into a high LMR group (n = 34) and a low LMR group (n = 128). The clinical data of the two groups were compared, and further stratified analysis was performed. A total of 162 patients were included in the analysis. All patients were successfully implanted with a thoracic aorta stent graft. The preoperative LMR level and postoperative endoleak-related secondary intervention rate were higher in the type I endoleak group than those in the group without intraoperative type I endoleaks. The preoperative C-reactive protein (CRP) level of patients with TAA with clinical symptoms was higher than that of asymptomatic patients. There was a negative correlation between preoperative CRP and LMR levels. In addition, in symptomatic or asymptomatic patients, the LMR level was associated with the occurrence of intraoperative type I endoleaks. After excluding the influence of type of endografts, our results showed that the clinical symptoms did not affect the occurrence of the intraoperative type I endoleak, and patients with intraoperative type I endoleak had a higher rate of postoperative secondary intervention. Patients with TAA with type I endoleaks during TEVAR had an increased rate of secondary intervention related to endoleaks. Patients with TAA with high LMR levels before TEVAR were more likely to have endoleaks during operation.

Prospective Multicentre Cohort Study of Fenestrated and Branched Endografts After Failed Endovascular Infrarenal Aortic Aneurysm Repair with Type Ia Endoleak

Failed endovascular infrarenal aortic aneurysm repair (EVAR) due to development of late type Ia endoleak exposes patients to the risk of rupture and should be treated. The purpose of this study was to evaluate the results of fenestrated/branched EVAR (F/BEVAR) for treatment of failed EVAR with type Ia endoleak. From January 2010 to December 2019, a prospective multicentre study was conducted (ClinicalTrials.gov identifier: NCT04532450) that included 85 consecutive patients who had undergone F/BEVAR to treat a type Ia endoleak following EVAR. The primary outcome was overall freedom from any re-intervention or death related to the F/BEVAR procedure. In 30 cases (35%) EVAR was associated with a short < 10 mm or angulated (> 60°) infrarenal aortic neck, poor placement of the initial stent graft (n= 3, 4%), sizing error (n= 2, 2%), and/or stent graft migration (n= 7, 8%). Type Ia endoleak was observed after a period of 59 ± 25 months following EVAR. The authors performed 82 FEVAR (96%) and three BEVAR (4%) procedures with revascularisation of 305 target arteries. Overall technical success was 94%, with three failures including one persistent Type Ia endoleak and two unsuccessful stent graft implantations. Intra-operative target artery revascularisation was successful in 303 of 305 attempts. The in hospital mortality rate was 5%. Cardiac, renal and pulmonary complications occurred in 6%, 14%, and 7% of patients, respectively. Post-operative spinal cord ischaemia occurred in four patients (4.7%). At three years, the survival rate was 64% with overall freedom from any re-intervention or aneurysm related death of 40%, and freedom from specific F/BEVAR re-intervention of 73%. At three years, the secondary patency rate of the target visceral arteries was 96%. During follow up, 27 patients (33%) required a revision procedure of the fenestrated (n= 11) or index EVAR stent graft (n= 16), including six open conversions. While manufactured F/BEVAR was effective in treating type Ia endoleak in patients with failed EVAR, it was at the cost of a number of secondary endovascular and open surgical procedures.

Can we replace computed tomography angiography by contrast-enhanced ultrasound in the surveillance of patients submitted to aortoiliac aneurysm repair?

This study was designed for evaluation of CEUS (contrast-enhanced ultrasound) for the detection of endoleaks after EVAR (endovascular aortic aneurysms repair) as an alternative to CTA (computed tomography angiography), the gold standard in post-EVAR surveillance. Post-EVAR surveillance of patients who underwent CEUS and CTA was retrospectively analyzed to compare the accuracy of CEUS compared to CTA. For that, the following parameters were analyzed: the largest aneurysm diameter, type of endoleaks, and the time elapsed after EVAR using both surveillance tests. The study involved 110 pairs of exams in patients with infrarenal aortoiliac or isolated iliac artery aneurysm, covering predominantly a male population (89%). The time elapsed after EVAR using CEUS or CTA exams were statistically similar, ranging from one to 58months (mean 12.2) and one to 65months (mean 9.7), respectively (p = 0.124). CEUS sensitivity was 75.5%, specificity 96.7%, false positives were 24.5%, and false negatives were 3.3%. The accuracy between the two exams was 87.3%. A secondary analysis, comparing CTA with CEUS as a reference standard, revealed CEUS sensitivity of 24.5%, higher than CTA for detecting endoleaks, with a concordance rate of true positive results of 75.5%. Among the endoleaks detected solely by CEUS (12 cases), one case was type Ia and eleven were type II, while those detected only by CTA (2 cases), one was type Ia and one type II. Additionally, a type II endoleak associated with type Ib, identified by CEUS, was seen as type II for CTA only. There was no difference between the pre-EVAR and the post-EVAR diameters of aortoiliac aneurysm (p = 0.058), both for CEUS and CTA. Computed tomography angiography, on the other hand, showed significant aneurysm diameter reduction compared to CEUS for isolated iliac artery aneurysms (p < 0.001). Contrast-enhanced ultrasound was more effective than CTA in identifying and characterizing endoleaks in patients undergoing EVAR, especially type II endoleaks. The advantages include efficacy and, particularly, safety, and must be considered in EVAR surveillance protocols so that its use becomes widespread. We understand that CEUS, as a surveillance exam, considerably reduces risks to patients compared to CTA.

The fate of endoleaks after endovascular aneurysm repair and the impact of oral anticoagulation on their persistence

BackgroundThe impact of anticoagulation on late endoleaks after endovascular aneurysm repair (EVAR) is unclear despite multiple investigators studying the relationship. The purpose of this study was to determine if long-term anticoagulation impacted the development of late endoleaks and if specific anticoagulants were more likely to exacerbate the development of endoleaks. MethodsUsing the Society for Vascular Surgery Vascular Quality Initiative database, patients undergoing EVAR between 2003 and 2019 for abdominal aortic aneurysms were evaluated. Patients were divided into two groups: those without a late endoleak and those with a late endoleak. Bivariate analysis was performed to assess preoperative, intraoperative, postoperative, and long-term follow-up variables. A multivariable analysis was done to determine associations of independent variables with late endoleaks. Patients were further subcategorized based on anticoagulation status before and after EVAR, specific type of anticoagulation, and the presence of an index endoleaks (diagnosed at the time of EVAR) to determine the subsequent frequency of late endoleaks. ResultsA total of 29,783 patients were analyzed with 2169 (7.3%) having a late endoleak identified. Several risk factors were related to late endoleaks, including anticoagulation before and after EVAR (odds ratio [OR], 4.23; 95% confidence interval [CI], 2.57-6.96; P < .001), anticoagulation after EVAR (OR, 1.88; 95% CI, 1.43-2.49; P < .001), and index endoleak (OR, 1.45; 95% CI, 1.26-1.66; P < .001). The frequency of late endoleaks in patients anticoagulated before and after EVAR and after EVAR as compared with those never anticoagulated was 16.89% and 14.40% vs 6.95%, respectively (both P > .001). No difference in late endoleaks were noted for patients treated with warfarin and novel oral anticoagulants. The most common type of index and late endoleak identified was type II, but patients with type I, type II, and type IV index endoleaks were more commonly found to have type I, type II, and type IV late endoleaks, respectively. The frequency of late endoleaks in patients with both an index endoleak and anticoagulation after EVAR was 20.42% as compared with patients with only anticoagulation after EVAR (14.63%; P = .0015) and with patients with index endoleaks not anticoagulated (10.06%; P < .00001). ConclusionsLate endoleaks were more common in patients treated with anticoagulation after EVAR. No difference in late endoleak frequency was detected between anticoagulation with warfarin and novel oral anticoagulants. Patients on anticoagulation and those with an index endoleak were at a higher risk of having a late endoleak.

Effect of limb oversizing on the risk of type Ib endoleak in patients after endovascular aortic repair

ObjectiveWe assessed the association between the degree of limb oversizing and the risk of type Ib endoleak (TIBEL) in different types of iliac landing zones after endovascular aortic aneurysm repair. MethodsWe performed a retrospective cohort study of patients who had undergone endovascular aortic aneurysm repair with bifurcated and limb endografts in an academic center. The main exposure was the degree of limb oversizing. The primary outcome was the occurrence of TIBELs. The secondary outcomes included limb occlusion, reintervention, and overall survival. Subgroup analyses stratified by ectatic and normal iliac landing zones were performed. Multivariate Cox regression analysis and sensitivity analyses using marginal structure model were conducted to adjust for potential confounders. ResultsA total of 750 patients with 1500 iliac limb endografts were included in our study (817 limbs with oversizing of ≤10% and 683 with oversizing >10%). The median 1-year freedom from TIBEL was 98.9% (interquartile range [IQR], 98.0%-99.8%) for limbs with oversizing of ≤10% and 99.6% (IQR, 99.0%-100%) for limbs with oversizing >10%. The median 3-year freedom from TIBEL was 95.6% (IQR, 93.1%-98.1%) and 98.2% (IQR, 96.5%-99.9%) for oversizing ≤10% and >10%, respectively. We found that limb oversizing >10% was associated with a significantly decreased risk of TIBEL (adjusted hazard ratio [HR], 0.38; 95% confidence interval [CI], 0.19-0.76) in the overall population. After stratification by ectatic iliac landing zone, we found that limb oversizing >10% was associated with a significantly decreased risk of TIBEL in the ectatic iliac landing zones (adjusted HR, 0.38; 95% CI, 0.16-0.88). However, no significant difference was found in the limb endografts landing in normal iliac arteries (adjusted HR, 0.44; 95% CI, 0.13-1.45). In the subgroup of normal iliac arteries, we observed a significantly increased risk of limb occlusion in the limbs with distal oversizing >15% compared with the limbs with distal oversizing of ≤15% (adjusted HR, 4.66; 95% CI, 1.68-12.91). ConclusionsAdequate limb oversizing >10% was associated with a significantly decreased risk of TIBEL in limbs with ectatic iliac landing zones. However, no additional benefit was observed for oversizing >10% in limb grafts landing in normal iliac arteries. Furthermore, excessive limb oversizing (>15%) in normal iliac landing zones can be associated with an increased risk of limb occlusion.

Long Term Outcomes of Endovascular Aortic Repair in Patients With Abdominal Aortic Aneurysm and Ectatic Common Iliac Arteries

The purpose of this study was to evaluate the long term results of endovascular aneurysm repair (EVAR) in patients with abdominal aortic aneurysm (AAA) and ectatic common iliac arteries (CIAs). In a retrospective analysis of a prospectively collected database in two high volume centres, patients with AAAs undergoing elective standard EVAR were divided into two groups: those with both CIA diameters <18mm, and those with at least one ectatic iliac artery (CIA≥18mm). Patients with an intentional external iliac artery landing zone were excluded. Primary outcomes were survival and freedom from re-intervention. Secondary end points were EVAR failure and iliac related endoleak and iliac re-intervention. From 2000 to 2015, 648 patients were included in the study, 277 (43%) had at least one CIA≥18mm. Pre-operative risk factors were similar between the two groups, with the exception of chronic renal insufficiency (p=.010) and cerebrovascular events (p=.040), which were higher in the ectatic CIA group. At 30 days from primary procedure, there was a higher rate of type Ib endoleak in patients with ectatic iliacs (p=.020). A statistically significant increase in the incidence of late type Ib endoleak in patients with ectatic iliac arteries was confirmed at a mean follow up of 74.8 months (p=.01). The need for iliac related re-intervention was higher in patients with CIAs ≥18mm (odds ratio 1.94; 95% confidence interval 1.1-3.2). Ectatic iliac arteries are considered suitable landing zones for EVAR, although there is an increased risk of secondary interventions in time mainly due to late CIA dilation and secondary type Ib endoleak. Patients receiving EVAR with flared iliac limbs may benefit a more intensive surveillance to avoid late failures.

Fabric Tears of Stent Graft Often Exist Among Aneurysm Sac Expansion After Endovascular Abdominal Aortic Aneurysm Repair

Introduction: Although type IIIb endoleaks caused by fabric tears are rare in endovascular abdominal aneurysm repair (EVAR) -related complications, they can lead to serious complications, including aneurysm expansion and eventual aneurysm rupture. Under the direct inspection in late open surgery for aneurysm sac expansion by persistent type II endoleak, we observed not only type II endoleak from patent lumber arteries but also type IIIb endoleak by fabric tears of an endovascular stent graft in several cases. There may be other types of endoleak, especially type IIIb, not diagnosed in pre-operation. There may be more type IIIb endoleak than we consider among aneurysm expansion by type II endoleak. Methods: Between January 2009 and December 2017, 182 patients underwent EVAR in our institution. Secondary intervention for sac diameter expansion by persistent type II endoleak was performed in 17 patients (9.3%). We examined peri-operative characteristics of the 17 patients. Results: For 16 out of 17 patients with type II endoleak at pre-secondary intervention, open surgery method was performed. Definitive diagnoses of endoleak type with intraoperative findings were type II only in 10 patients, type II and type IIIb in 6 patients (38%). The devices used for the 6 patients who diagnosed type II and type IIIb were Zenith 2, Excluder 2, Endurant 1 and AFX 1. Operative procedures for 10 type II only patients were, bifurcated graft repair in 2 patients, and open ligation of lumber arteries in 8 patients. For type II and type IIIb patients, open ligation of lumber arteries was performed for type II endoleak, then for type IIIb procedure, a suture hemostasis was selected in 4 patients, and an additional leg insertion in 2 patients. All patients' postoperative course was uneventful, and in-hospital death was 0 patient. Conclusion: Our experience demonstrated that there is a possibility of complex condition with not only type II endoleak but also type IIIb endoleak in patients with type II endoleak in pre-operative diagnosis. Although type IIIb endoleak is often difficult to detect, there were much more type IIIb endoleak than we consider. We should note that type IIIb endoleak caused by fabric tears of stent graft is present among sac expansion after EVAR. Disclosure: Nothing to disclose

Angio PL.U.S. (PLanewave UltraSensitive Imaging) as a Novel Doppler Ultrasound Technique with Potential to Evaluation Endoleaks in Patients After Endovascular Aneurysm Repair (EVAR)

Angio PL.U.S. (PLanewave UltraSensitive Imaging) as a Novel Doppler Ultrasound Technique with Potential to Evaluation Endoleaks in Patients After Endovascular Aneurysm Repair (EVAR)

Natural history of isolated type II endoleaks in patients treated by fenestrated-branched endovascular repair for pararenal and thoracoabdominal aortic aneurysms

ObjectiveType II endoleaks (T2ELs) are common after endovascular aneurysm repair (EVAR), but little is known about their natural history in patients treated by fenestrated-branched EVAR (F/BEVAR). We sought to evaluate the natural history of isolated T2EL after F/BEVAR for pararenal aortic aneurysms (PRAs) and thoracoabdominal aortic aneurysms (TAAAs). MethodsConsecutive patients enrolled in a prospective nonrandomized study to investigate F/BEVAR for PRAs and TAAAs at a single institution (2014-2017) were identified. Computed tomography angiography images at discharge and during follow-up were reviewed. Patients with ≥12 months of follow-up were included and divided in two groups for comparison based on the presence or absence of T2ELs. Patients with any non-T2ELs were excluded. Multivariable logistic regression was used to assess factors associated with T2EL occurrence. Primary outcomes were absolute and relative sac diameter change and sac diameter increase >5 mm. Secondary outcomes included overall survival, aorta-related death, reinterventions, and conversion or rupture. ResultsThere were 184 patients (136 male [74%]) with PRAs (n = 70 [38%]) and TAAAs (n = 114 [62%]) with an average age of 74 ± 7 years included. Isolated T2ELs were seen in 76 patients (41%); of these, 71 T2ELs (93%) were primary. Patients with T2ELs were more likely to have larger aneurysms (mean baseline diameter, 66 ± 8 mm vs 63 ± 8 mm; P = .01), patent inferior mesenteric artery (66% vs 32%; P < .001), and more lumbar arteries (mean, 6 ± 1 vs 4 ± 1; P < .001). In the multivariable analysis, these were all independently associated with T2EL occurrence. Of all T2ELs, only 18 (24%) resolved spontaneously during a mean follow-up of 31 ± 15 months. Mean absolute sac diameter reduction for patients without T2ELs and with T2ELs, at 12 and 36 months, was 10.2 ± 5.9 mm vs 2.6 ± 6.4 mm and 16.3 ± 7.3 mm vs 5.7 ± 11.3 mm, respectively (P < .001). For the same groups, the mean percentage sac diameter reduction at 12 and 36 months was 16.4% ± 9.4% vs 3.8% ± 9.8% and 26.4% ± 11.6% vs 8.8% ± 17.7%, respectively (P < .001). Overall, 13 patients showed sac increase >5 mm, and all these instances were recorded in the T2EL group; 8 required reintervention. T2ELs were not associated with decreased overall survival, freedom from aorta-related death, or freedom from any reintervention. ConclusionsIsolated T2ELs are common after F/BEVAR for PRAs and TAAAs, usually seen early; they are most often associated with inferior mesenteric or lumbar artery flow and tend to persist in follow-up. Their presence is associated with impaired sac shrinkage and risk of sac growth with subsequent need for secondary interventions. Although not associated with decreased overall survival or loss of freedom from aorta-related death, T2ELs require serial imaging surveillance.

Correlation of Baseline Plasma and Inguinal Connective Tissue Metalloproteinases and Their Inhibitors With Late High-Pressure Endoleak After Endovascular Aneurysm Repair: Long-term Results

Purpose: To investigate whether plasma and connective tissue matrix metalloproteinases (MMP) and their inhibitors (TIMP) may predict late high-pressure endoleak after endovascular aneurysm repair (EVAR). Materials and Methods: Samples of inguinal fascia and blood were collected in 72 consecutive patients (mean age 73.1 years; 68 men) undergoing primary EVAR with the Endurant stent-graft. Baseline plasma levels of MMP-2, MMP-9, TIMP-1, and TIMP-2 and baseline MMP-2 and MMP-9 activity estimated using gelatin zymography (GZ) were compared between patients who developed late endoleak in follow-up and those who did not. Subgroup analyses were performed between patients with (n=18) and without inguinal hernias and between patients with moderate-diameter (50–59 mm; n=45) or large-diameter (≥60 mm; n=27) abdominal aortic aneurysms (AAA) at primary EVAR. Results: The mean follow-up period was 63.1 months (range 7.5–91.5), during which time 13 (18.1%) patients developed type I (6 Ia and 5 Ib) or 2 type III endoleaks. Only GZ-analyzed proMMP-9 concentrations were higher in the endoleak group than in patients without endoleak (mean difference 8.44, 95% CI −19.653 to −1.087, p=0.03). The patients with primary inguinal hernia at presentation had significantly higher tissue TIMP-2 values (0.8±0.7 vs 0.5±0.4, p=0.018) but lower plasma total (pro- + active) MMP-9 values (11.9±7.8 vs 16.2±7.4, p=0.042) than patients without hernias at the time of EVAR. Patients with AAAs ≥60 mm had significantly higher mean tissue homogenate levels of total (pro- + active) MMP-9 (p=0.025) and total (pro- + active) MMP-2 (p=0.049) as well as higher proMMP-9 (p=0.018) and total (pro- + active) MMP-9 (p=0.021) levels based on GZ compared to patients with moderate-diameter AAAs. Regression analysis revealed a significant association between total (pro- + active) MMP-9 plasma samples and the presence of hernia (OR 0.899, 95% CI 0.817 to 0.989, p=0.029) and between GZ-analyzed proMMP-9 and late endoleak (OR 1.055, 95% CI 1.007 to 1.106, p=0.025). GZ-analyzed proMMP-9 and active MMP-9 were strong predictors of late endoleak in patients with hernia (p=0.012 and p=0.044, respectively) and in patients with AAAs ≥60 mm (p=0.018 and p=0.041 respectively). Conclusion: Inguinal fascial tissue proMMP-9 significantly predicted late endoleak. ProMMP-9 and active MMP-9 biomarkers are significantly associated with late endoleak in hernia patients and in patients with AAAs ≥60 mm. Considering the clinical association between hernia and AAA and the fact that the AAA wall connective tissue environment remains exposed to systemic circulation after EVAR, inguinal fascia extracellular matrix dysregulation and altered MMP activity may reflect similar changes in AAA biology, leading to complications such as endoleak.

Type II Endoleak With an Enlarging Aortic Sac Predisposes to Development of Type IA Endoleak

The most common endoleak after endovascular aneurysm repair is type II. Whereas type II endoleaks (T2ELs) are generally considered benign, there have been reports that they can lead to aortic rupture. In this report, we reviewed the effect of T2EL on sac size changes to determine whether sac expansion due to a T2EL could result in the development of a type IA endoleak. Following Institutional Review Board approval, all aortoiliac endovascular aneurysm repairs performed at a single institution between June 2006 and June 2012 were retrospectively reviewed. Demographics, comorbidities, aneurysm diameter, graft type, need for reintervention, and complications were collected. Patients with T2EL diagnosed on follow-up imaging were categorized as those who underwent intervention for the T2EL and those who did not. Outcomes were tabulated with attention to sac size change, development of type IA endoleak, rupture, and survival. During the study period, 627 patients underwent aortoiliac stent graft placement at our institution. Patients with an operative indication other than nonruptured infrarenal abdominal aortic aneurysm and those who did not have a preoperative computed tomography angiography image available or follow-up data were excluded. The total number of patients included was 389, with an average follow-up of 68.8 months (range, 0-194 months). Follow-up imaging diagnosed 122 patients with T2EL (31%). Patients with T2EL were significantly more likely to have a smoking history (P = .01), hypertension (P < .05), and older age (P < .0001). Patients with T2EL had a significantly larger sac size increase than patients without T2EL (9.50 vs −0.78 mm; P < .0001). Patients with T2EL were significantly more likely to develop a type IA endoleak than patients who did not have T2EL (14% vs 6%; P = .02), but the rate of rupture was not significantly different (4% vs 2%; P = .33). Those patients in the T2EL group who underwent intervention for T2EL survived significantly longer than patients who did not undergo intervention (100.5 vs 75 months; P = .004). Our data suggest that there is an increased incidence of late type IA endoleak in patients with T2EL and an enlarging aortic sac. Our study also demonstrates an increased overall survival in T2EL patients who underwent intervention. Future studies are necessary to better define the association between T2EL with enlarging sac and the development of type IA endoleak.