The Gore Viabahn balloon-expandable stent graft as a bridging stent in complex endovascular aortic procedures at 3 years performs better in fenestrations.

OBJECTIVE: Complex endovascular procedures are now recognized as the gold standard treatments for extensive aortic diseases. Bridging stents (covered stents used to couple the aortic graft to the visceral vessels) play a pivotal role, yet there is currently no dedicated device available on the market. The aim of the study was to evaluate the midterm performance of the Gore Viabahn balloon-expandable (VBX) stent graft as a bridging stent for target visceral vessels (TVVs). METHODS: Data from all consecutive patients who underwent a fenestrated and branched endovascular aortic repair and received the VBX stent graft as a bridging stent between July 2018 and September 2022 were prospectively collected and subsequently analyzed retrospectively. Primary end points included freedom from TVV instability and freedom from TVV-related reinterventions, both overall and in comparison between branched and fenestrated graft configurations. Secondary end points were overall survival, procedure and TVV-related (in an intent-to-treat basis) technical success, freedom from type IC/IIIC endoleak, and freedom from TVV patency loss. RESULTS: Sixty-three patients were treated with a fenestrated and branched endovascular aortic repair using the VBX stent graft as a bridging stent, of whom 47 (74.6%) presented an atherosclerotic aneurysm, 7 (11.1%) a post-dissecative aneurysm, and 9 (14.3%) an anastomotic pseudoaneursym or a type IA endoleak in a previous endovascular aortic repair. Included in the aortic repair were 231 of 243 (95.1%) total visceral vessels. The intraoperative requirement of 13 additional VBX stent grafts determined a TVV-related technical success of 94.4%. The mean follow-up was 26.1 ± 16.4 months. The estimated overall survival at 36 months was 73% ± 7.5%. The estimated rates at 36 months for freedom from type IC/IIIC endoleaks and TVV primary patency were 90.6% ± 3.9% and 99% ± 0.7%, respectively. The estimated rate at 36 months for freedom from TVV instability was 92.1% ± 3% and did not differ between branched and fenestrated configurations, whereas freedom from TVV-related reinterventions was 90.6% ± 3.1% and significantly in favor of fenestrations (69.4% vs 96.8%, P < .001). Multivariate analyses confirmed fenestrated configuration as a protective factor against TVV-related reinterventions (hazard ratio: 0.079; 95% confidence interval: 0.016-0.403). CONCLUSIONS: The VBX stent graft proves to be a reliable bridging stent for complex aortic procedures involving both fenestrated and branched endografts. Although immediate results are deemed satisfactory, they favor fenestrations regarding the need of reinterventions through 3 years. The success of the procedure heavily relies on a thorough understanding of the unique characteristics of this stent.

Nellix Device Failure Mechanisms Analysis on Explanted Grafts.

OBJECTIVE: To understand possible reasons for poor durability of the Nellix (Endologix Inc., Irvine, USA) endovascular aneurysm sealing (EVAS) device. MATERIALS AND METHODS: 21 Nellix endoprostheses explanted for endoleaks and migration underwent visual examinations of stent structures and instrumental examinations of the polymer endobags on 4 devices. We harvested 2.0-gram polymer slices out of each of them and tested the samples in an in vitro implantation replication that included wet and dry exposures. During the wet phase, we placed samples in a beaker with saline, mimicking the filling of the endobags during implantation. An exposure to a 37°C environment with 60% humidity during the dry phase replicated the postimplantation conditions inside the aneurysmal sac. RESULTS: Iatrogenic defects affected 16 (76%) metal stents and 20 (95%) endobags. The polymer was disintegrated owing to degradation in 15 (71%) cases. The polymer could lose more than 70% of its initial weight when partially dehydrated and regain 80% when placed in saline. We observed volume decrease and polymer fragmentation during these study phases. CONCLUSIONS: The polymer can lose weight and volume while it dehydrates. This structural degradation of the polymer could lead to the development of endoleaks and/or migration of the device. CLINICAL IMPACT: Based on the results of previous investigations, due to possible endovascular device degradation, patients with endografts should be offered life-long surveillance, and the Nellix device is no exception. Herein we suggest polymer degradation as one of the possible reasons for the device failure. Although Nellix has been withdrawn from the market, there are numerous patients with this type of endograft. Due to its unpredictable performance in the medium and long term, these patients should be recommended enhanced life-long surveillance every 6 months. Any suspicious conditions during the follow-up must be taken seriously and explantation should be considered.

Endovascular repair for infra-renal aortic aneurysms with supra-renal fixation endoprosthesis: Results and outcomes.

OBJECTIVE: The main objective of this paper is to evaluate the outcomes regarding endoleaks, reinterventions, and death related to aneurysm complications in patients submitted to endovascular repair (EVAR) for abdominal aortoiliac aneurysm (AAA) using Endurant II (Medtronic) and Zenith Flex (Cook) endografts. METHODS: This was a prospective, consecutive cohort study of patients with AAA who underwent EVAR with the use of Endurant II stent graft and Zenith Flex endograft. RESULTS: A total of 156 patients submitted to EVAR were evaluated. The perioperative mortality was 5.1%, 8 patients. The median clinical follow-up period was 760 ± 80 days. There were 28 patients (17.9%) submitted to urgent repair of the aneurysm (symptomatic expansion or rupture) and 128 patients (82.1%) submitted to elective repair. There were 36 cases (23.1%) of later endoleak and most of them are Type II endoleaks (21 patients, 13.4%). There were 12 cases of Type I endoleak. Moreover, regarding limb graft occlusion (LGO), there were 9 patients (5.8%). The overall survival rate in Kaplan-Meier analysis at 720 days was 84.8% in the total cohort. The freedom from reintervention rate in Kaplan-Meier analysis at 720 days was 92.7% in the total cohort. The linear regression analysis for survival rates showed that chronic kidney disease (p = .03; hazard ratio (HR) = 2.82, CI = 1.07-4.44) was the only factor related to poorer survival rates in both univariate and multivariate analyses. The linear regression analysis showed that the presence of endoleaks (p < .001, HR = 6.69, CI = 2.26-8.48) and limb graft occlusion (p < .001, HR = 8.02, CI = 1.60-9.99) were related to reintervention in both univariate and multivariate analyses. CONCLUSION: In this present study, supra-renal fixation endograft devices were safe and efficient in treating AAA, with satisfactory results and no renal compromise. The linear regression analysis showed that the presence of endoleaks and limb graft occlusion were related to higher reintervention rates in both univariate and multivariate analyses.

Intraoperative evaluation for endoleaks using the SCORPION procedure during endovascular aortic repair.

OBJECTIVES: Endoleaks are important complications of endovascular aortic repair. Usually, endoleaks are judged indirectly by aortography or postoperative computed tomography. However, findings from these modalities are difficult to distinguish because of the divergency of endoleaks. Few studies have reported direct visualization of endoleaks. Herein, we introduce a direct procedure for intraoperatively evaluating endoleaks using angioscopy. METHODS: From April 2023, consecutive patients with an abdominal aortic aneurysm, except emergency cases and those of narrow access, seen at Sunagawa City Medical Center were enrolled in our study. Endoleaks were detected by intraoperative angioscopy using a novel endovascular procedure. RESULTS: Seven patients underwent endovascular aortic repair of an abdominal aortic aneurysm with intraoperative angioscopy. None of the enrolled patients experienced complications. The procedure revealed types 2, 3a, and 4 endoleaks. CONCLUSIONS: This is the first study to demonstrate intraoperative visualization of endoleaks using angioscopy. Direct findings observed by this novel procedure might provide information on the velocity and volume of the endoleak, providing comprehensive insights into the intra-sac hemodynamics after the endovascular aortic repair.

Endovascular Treatment of Abdominal Aortic Aneurysm: Impact of Diabetes on Endoleaks and Reintervention.

Background: Diabetes has a protective effect on abdominal aortic aneurysms (AAAs); however, there are contrasting reports on the impact of diabetes on endovascular aortic repair (EVAR) outcomes, endoleaks (ELs) being the major negative outcome. The present study characterizes ELs and their outcomes in AAA patients, diabetic or not. Methods: This single-center, retrospective, comparative study was carried out on 324 AAA patients who underwent elective EVARs between 2007 and 2016 at the University Hospital of Liège (Belgium). The primary endpoint was the incidence and effect of ELs on the evolution of the aneurysmal sac; the secondary endpoints were surgical reintervention and mortality rate. Diabetic and non-diabetic patients were compared with respect to various risk factors by logistic regression, while a Cox regression was used to analyze survival. Results: In AAA patients meeting the inclusion criteria (n = 248), 23% were diabetic. EL incidence was comparable (p = 0.74) in diabetic (38.7%) vs. non-diabetic (43.9%) patients. EL risk factors were age (HR = 1.04, p = 0.014) and fibrate intake (HR = 3.12, p = 0.043). A significant association was observed between ELs and aneurysm sac enlargement (p < 0.001), regardless of group (p = 0.46). Aneurysm sac regression per month for non-diabetic patients was -0.24 ± 0.013, while for diabetics it was -0.18 ± 0.027 (p = 0.059). Dyslipidemia (HR = 3.01, p = 0.0060) and sulfonylureas (HR = 8.43, p = 0.043) were associated with shorter EL duration, while diabetes (HR = 0.080, p = 0.038) and beta blockers (HR = 0.46, p = 0.036) were associated with longer EL duration. The likelihood of reoperation decreased with more recent surgery (OR = 0.90, p = 0.040), regardless of diabetic status. All-cause mortality was higher for the non-diabetic group (45.5% vs. 26.3%, p = 0.0096). Conclusions: Endoleak occurrence is a known risk factor for sac expansion. In diabetic patients, endoleaks lasted longer, and regression of the aneurysm sac tended to be slower. The number and type of reintervention was not related to the diabetic status of AAA patients, but overall survival was higher in patients with diabetes.

Postdissection aortic aneurysm sac enlargement after fenestrated and branched endovascular aortic aneurysm repair.

OBJECTIVES: Aneurysm sac changes after fenestrated-branched endovascular aneurysm repair (FBEVAR) for postdissection thoracoabdominal aortic aneurysms (PD-TAAs) are poorly understood. Partial thrombosis of the false lumen and endoleaks may impair sac regression. To characterize sac changes after FBEVAR for PD-TAAs, this study examined midterm results and predictors for sac enlargement. METHODS: FBEVARs performed for PD-TAAs in 10 physician-sponsored investigational device exemption studies from 2008 to 2023 were analyzed. The maximum aortic aneurysm diameter was compared between the 30-day computed tomography angiogram and follow-up imaging studies. Aneurysm sac enlargement was defined as an increase in diameter of ≥5 mm. Kaplan-Meier curves and Cox regression were used to evaluate sac enlargement and midterm FBEVAR outcomes. RESULTS: Among 3296 FBEVARs, 290 patients (72.4% male; median age, 68.4 years) were treated for PD-TAAs. Most aneurysms treated were extent II (72%) and III (12%). Mean aneurysm diameter was 66.5 ± 11.2 mm. Mortality at 30 days was 1.4%. At a mean follow-up of 2.9 ± 1.9 years, at least one follow-up imaging study revealed sac enlargement in 43 patients (15%), sac regression in 115 patients (40%), and neither enlargement nor regression in 137 (47%); 5 (2%) demonstrated both expansion and regression during follow-up. Freedom from aneurysm sac enlargement was 93%, 82%, and 80% at 1, 3, and 5 years, respectively. Overall, endoleaks were detected in 27 patients (63%) with sac enlargement and 143 patients (58%) without enlargement (P = .54). Sac enlargement was significantly more frequent among older patients (mean age at the index procedure, 70.2 ± 8.9 years vs 66.5 ± 11 years; P = .04) and those with type II endoleaks at 1 year (74% vs 52%; P = .031). Cox regression revealed age >70 years at baseline (hazard ratio [HR], 2.146; 95% confidence interval [CI], 1.167-3.944; P = .010) and presence of type II endoleak at 1 year (HR, 2.25; 95% CI, 1.07-4.79; P = .032) were independent predictors of sac enlargement. Patient survival was 92%, 81%, and 68% at 1, 3, and 5 years, respectively. Cumulative target vessel instability was 7%, and aneurysm-related mortality was 2% at 5 years. At least 42% of patients required secondary interventions. Sac enlargement did not affect patient survival. CONCLUSIONS: Aneurysm sac enlargement occurs in 15% of patients after FBEVAR for PD-TAAs. Elderly patients (>70 years at baseline) and those with type II endoleaks at 1 year may need closer monitoring and secondary interventions to prevent sac enlargement. Despite sac enlargement in some patients, aneurysm-related mortality at 5 years remains low and overall survival was not associated with sac enlargement.

Prediction of endovascular leaks after thoracic endovascular aneurysm repair though machine learning applied to pre-procedural computed tomography angiographs.

To predict endoleaks after thoracic endovascular aneurysm repair (TEVAR) we submitted patient characteristics and vessel features observed on pre- operative computed tomography angiography (CTA) to machine-learning. We evaluated 1-year follow-up CT scans (arterial and delayed phases) in patients who underwent TEVAR for the presence or absence of an endoleak. We evaluated the effect of machine learning of the patient age, sex, weight, and height, plus 22 vascular features on the ability to predict post-TEVAR endoleaks. The extreme Gradient Boosting (XGBoost) for ML system was trained on 14 patients with- and 131 without endoleaks. We calculated their importance by applying XGBoost to machine learning and compared our findings between with those of conventional vessel measurement-based methods such as the 22 vascular features by using the Pearson correlation coefficients. Pearson correlation coefficient and 95% confidence interval (CI) were r = 0.86 and 0.75 to 0.92 for the machine learning, r = - 0.44 and - 0.56 to - 0.29 for the vascular angle, and r = - 0.19 and - 0.34 to - 0.02 for the diameter between the subclavian artery and the aneurysm (Fig. 3a-c, all: p < 0.05). With machine-learning, the univariate analysis was significant higher compared with the vascular angle and in the diameter between the subclavian artery and the aneurysm such as the conventional methods (p < 0.05). To predict the risk for post-TEVAR endoleaks, machine learning was superior to the conventional vessel measurement method when factors such as patient characteristics, and vascular features (vessel length, diameter, and angle) were evaluated on pre-TEVAR thoracic CTA images.

Mid-term outcomes of physician-modified endograft therapy for complex aortic aneurysms.

OBJECTIVES: Our goal was to evaluate early and mid-term outcomes of physician-modified endografting for pararenal and thoraco-abdominal aortic aneurysms from 10 Japanese aortic centres. METHODS: From January 2012 to March 2022, a total of 121 consecutive adult patients who underwent physician-modified endografting for pararenal and thoraco-abdominal aortic aneurysms were enrolled. We analysed early and mid-term postoperative outcomes, including postoperative complications and mortality. RESULTS: The pararenal and thoraco-abdominal aortic aneurysm groups included 62 (51.2%) and 59 (48.8%) patients, respectively. The overall in-hospital mortality rate was 5.8% (n = 7), with mortality rates of 3.2% (n = 2) and 8.5% (n = 5) in pararenal and thoraco-abdominal aortic aneurysm groups, respectively (P = 0.225). Type IIIc endoleaks occurred postoperatively in 18 patients (14.9%), with a significantly higher incidence (P = 0.033) in the thoraco-abdominal aortic aneurysm group (22.0%, n = 13) than in the other group (8.1%, n = 5). Major adverse events occurred in 7 (11.3%) and 14 (23.7%) patients in pararenal and thoraco-abdominal aortic aneurysm groups (P = 0.074), respectively. The mean follow-up period was 24.2 months. At the 3-year mark, both groups differed significantly in freedom from all-cause mortality (83.3% and 54.1%, P = 0.004), target aneurysm-related mortality (96.8% and 82.7%, P = 0.013) and any reintervention (89.3% and 65.6%, P = 0.002). Univariate and multivariate regression analyses demonstrated that ruptures, thoraco-abdominal aortic aneurysms and postoperative type IIIc endoleaks were associated with an increased risk of all-cause mortality. CONCLUSIONS: The mid-term outcomes of physician-modified endografting for pararenal and thoraco-abdominal aortic aneurysms were clinically acceptable and comparable with those in other recently published studies. Notably, pararenal and thoraco-abdominal aortic aneurysms represent distinct pathological entities with different postoperative outcomes.

Multi-Energy Low-Kiloelectron Volt versus Single-Energy Low-Kilovolt Images for Endoleak Detection at CT Angiography of the Aorta.

Purpose To compare image quality, diagnostic performance, and conspicuity between single-energy and multi-energy images for endoleak detection at CT angiography (CTA) after endovascular aortic repair (EVAR). Materials and Methods In this single-center prospective randomized controlled trial, individuals undergoing CTA after EVAR between August 2020 and May 2022 were allocated to imaging using either low-kilovolt single-energy images (SEI; 80 kV, group A) or low-kiloelectron volt virtual monoenergetic images (VMI) at 40 and 50 keV from multi-energy CT (80/Sn150 kV, group B). Scan protocols were dose matched (volume CT dose index: mean, 4.5 mGy ± 1.8 [SD] vs 4.7 mGy ± 1.3, P = .41). Contrast-to-noise ratio (CNR) was measured. Two expert radiologists established the reference standard for the presence of endoleaks. Detection and conspicuity of endoleaks and subjective image quality were assessed by two different blinded radiologists. Interreader agreement was calculated. Nonparametric statistical tests were used. Results A total of 125 participants (mean age, 76 years ± 8; 103 men) were allocated to groups A (n = 64) and B (n = 61). CNR was significantly lower for 40-keV VMI (mean, 19.1; P = .048) and 50-keV VMI (mean, 16.8; P < .001) as compared with SEI (mean, 22.2). In total, 45 endoleaks were present (A: 23 vs B: 22). Sensitivity for endoleak detection was higher for SEI (82.6%, 19 of 23; P = .88) and 50-keV VMI (81.8%, 18 of 22; P = .90) as compared with 40-keV VMI (77.3%, 17 of 22). Specificity was comparable among groups (SEI: 92.7%, 38 of 41; both VMI energies: 92.3%, 35 of 38; P = .99), with an interreader agreement of 1. Conspicuity of endoleaks was comparable between SEI (median, 2.99) and VMI (both energies: median, 2.87; P = .04). Overall subjective image quality was rated significantly higher for SEI (median, 4 [IQR, 4-4) as compared with 40 and 50 keV (both energies: median, 4 [IQR, 3-4]; P < .001). Conclusion SEI demonstrated higher image quality and comparable diagnostic accuracy as compared with 50-keV VMI for endoleak detection at CTA after EVAR. Keywords: Aneurysms, CT, CT Angiography, Vascular, Aorta, Technology Assessment, Multidetector CT, Abdominal Aortic Aneurysms, Endoleaks, Perigraft Leak Supplemental material is available for this article. © RSNA, 2024.

Review of Clinical Applications of Dual-Energy CT in Patients after Endovascular Aortic Repair.

Abdominal aortic aneurysms (AAAs) are a significant cause of mortality in developed countries. Endovascular aneurysm repair (EVAR) is currently the leading treatment method for AAAs. Due to the high sensitivity and specificity of post-EVAR complication detection, CT angiography (CTA) is the reference method for imaging surveillance in patients after EVAR. Many studies have shown the advantages of dual-energy CT (DECT) over standard polyenergetic CTA in vascular applications. In this article, the authors briefly discuss the technical principles and summarize the current body of literature regarding dual-energy computed tomography angiography (DECTA) in patients after EVAR. The authors point out the most useful applications of DECTA in this group of patients and its advantages over conventional CTA. To conduct this review, a search was performed using the PubMed, Google Scholar, and Web of Science databases.

Beyond Diameter: Enhancing Abdominal Aortic Aneurysm Surveillance with Volumetric Assessments after Endovascular Aneurysm Repair (EVAR).

This study aimed to investigate the relationship between maximum transverse diameter (MTD) and volume measurements in patients who underwent reoperations after endovascular aneurysm repair (EVAR), and their association with the occurrence of endoleaks. The study included 51 patients who underwent EVAR and subsequent re-operations caused by endoleaks type I-III. In some number of events, multiple re-operations were needed. MTD was measured using the Horos software, and segmentations of the AAA were performed using 3D Slicer. This study first evaluated post-operative computed tomography angiography (CTA) to measure MTD and volume. Then, similar measurements were made in the control scan for re-operation qualification. Negative remodeling (increase in MTD and/or volume) was observed in 40 cases using MTD, and 48 cases using volume measurements. The volume measurement showed lower missed negatives than MTD, indicating its effectiveness in screening for negative remodeling (p < 0.001). Combining both methods identified 51 negative remodeling cases and 8 positive changes, with a higher sensitivity compared to MTD alone. The volume of the sac did not predict specific endoleak types. Decreases in MTD were observed in smaller sacs, with smaller volume changes. Volume measurement is a valuable screening tool, and combining MTD and volume enhances sensitivity. However, sac volume does not predict endoleak type.

A Single Centre Long Term Follow Up of the Nellix Endovascular Aneurysm Sealing System.

OBJECTIVE: To evaluate the clinical performance at long term follow up of endovascular aneurysm sealing (EVAS, Endologix Inc. Nellix, Irvine, CA, USA) in the treatment of abdominal aortic aneurysm (AAA). METHODS: Observational, prospective, single centre study of primary AAA interventions with EVAS (n = 117) from November 2013 to November 2016. Endpoints were primary technical success, Nellix device failure, freedom from open surgical conversion (OSC), freedom from secondary intervention, sac rupture, total mortality, and aneurysm related mortality at long term follow up. RESULTS: The median age was 75 years (interquartile range [IQR] 70, 81 years) and 83% were male. The median AAA diameter was 58 mm (IQR 54, 60 mm). The median length of follow up was 6.2 years (IQR 5.6, 6.8 years). Primary technical success was 100%. Median time to Nellix failure was 5.6 years (IQR 3.3, 7.4 years). Freedom from Nellix failure at five and seven years was 54% (95% confidence interval [CI] 54.2 - 63.8%) and 36% (95% CI 22.3 - 49.7%), respectively. Freedom from OSC at five and seven years was 63% (95% CI 53.2 - 72.8%) and 59% (95% CI 47 - 71%), respectively. The secondary intervention rate was 11.4/100 person years. Freedom from secondary intervention at five and seven years was 52% (95% CI 42.2 - 61.8%) and 51% (95% CI 41.2 - 60.8%), respectively. The cumulative mortality rate at five and seven years was 36% and 54%, respectively. Secondary sac rupture occurred in 9.4% (11/117) with a rate of 2/100 person years. Aneurysm related mortality was 12% (14/117) with a rate of 2.5/100 person years. The median survival was four years (IQR 3, 5.6 years). Thirty day mortality for acute OSC was 67% (n = 3) and 17.1% (6/35) for elective OSC. CONCLUSION: Long term follow up showed an increased failure rate. Diligent surveillance after endovascular AAA treatment is mandatory, especially when promising new devices are put into clinical use.

A multidisciplinary approach: Case report of an abdominal aortic aneurysm with type IIIA endoleak in the setting of cholangitis.

Endoleaks are a common complication of endovascular aortic aneurysm repair and often lead to aneurysm rupture. We report a complex case of a Type IIIA endoleak in a patient with suspected cholangitis. Immediate surgical measures to manage both the cholangitis and endoleak were performed while minimizing the risk of graft infection.

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.

Fate of target visceral vessels in fenestrated and branched complex endovascular aortic repair.

OBJECTIVE: To assess branch vessel outcomes after endovascular repair of complex aortic aneurysms analyzing possible factors influencing early and long-term results. METHODS: The Italian Multicentre Fenestrated and Branched registry enrolled 596 consecutive patients treated with fenestrated and branched endografts for complex aortic disease from January 2008 to December 2019 by four Italian academic centers. The primary end points of the study were technical success (defined as target visceral vessel [TVV] patency and absence of bridging device-related endoleak at final intraoperative control), and freedom from TVV instability (defined as the combined results of type IC/IIIC endoleaks and patency loss) during follow-up. Secondary end points were overall survival and TVV-related reinterventions. RESULTS: We excluded 591 patients (3 patients with a surgical debranching and 2 patients who died before completion from the study cohort) were treated for a total of 1991 visceral vessels targeted by either a directional branch or a fenestration. The overall technical success rate was 98.4%. Failure was related to the use of an off-the-shelf (OTS) device (custom-made device vs OTS, HR, 0.220; P = .007) and a preoperative TVV stenosis of >50% (HR, 12.460; P < .001). The mean follow-up time was 25.1 months (interquartile range, 3-39 months). The overall estimated survival rates were 87%, 77.4%, and 67.8% at 1, 3, and 5 years, respectively (standard error [SE], 0.015, 0.022, and 0.032). During follow-up, TVV branch instability was observed in 91 vessels (5%): 48 type IC/IIIC endoleaks (2.6%) and 43 stenoses-thromboses (2.4%). The extent of aneurysm disease (thoracoabdominal aortic aneurysm [TAAA] types I-III vs TAAA type IV/juxtarenal aortic aneurysm/pararenal aortic aneurysm) was the only independent predictor for developing a TVV-related type IC/IIIC endoleak (HR, 3.899; 95% confidence interval [CI]:, 1.924-7.900; P < .001). Risk of patency loss was independently associated with branch configuration (HR, 8.883; P < .001; 95% CI, 3.750-21.043) and renal arteries (HR, 2.848; P = .030; 95% CI, 1.108-7.319). Estimated rates at 1, 3, and 5 years of freedom from TVV instability and freedom from TVV-related reintervention were 96.6%, 93.8%, and 90% (SE, 0.005, 0.007, and 0.014) and 97.4%, 95.0%, and 91.6% (SE, 0.004, 0.007, and 0.013), respectively. CONCLUSIONS: Intraoperative failure to bridge a TVV was associated with a preoperative TVV stenosis of >50% and the use of OTS devices. Midterm outcomes were satisfying, with an estimated 5-year freedom from TVV instability and reintervention of 90.0% and 91.6%, respectively. During follow-up, the larger extent of aneurysm disease was associated with an increased risk of TVV-related endoleaks, whereas a branch configuration and renal arteries were more prone to patency loss.

The efficacy and safety of Gore conformable thoracic stent graft and Valiant Captivia thoracic stent graft for acute type B aortic dissection.

BACKGROUND: To evaluate the safety and efficacy of the conformable thoracic aortic endograft (Conformable TAG Thoracic Endoprosthesis [CTAG]; W. L. Gore & Associates, Flagstaff, Ariz) and Valiant Captivia thoracic stent graft (Medtronic Inc., Santa Rosa, CA) for acute type B aortic dissection (TBAD). METHODS: The early and mid-term outcomes were analyzed for 413 patients undergoing TEVAR using conformable TAG thoracic endoprosthesis and Valiant Captivia thoracic stent graft for acute TBAD. 100 propensity-matched pairs of patients were generated, including 100 patients in the CTAG group and 200 patients in the Valiant Captivia group. RESULTS: Operative mortality were 2.33% (3 of 129) in the CTAG group and 1.76% (5 of 284) in the Valiant Captivia group. The median follow-up was 41.67 (26.00-60.67) months. No significant difference in mortality (9 [7.00%] vs. 36 [12.68%], P = 0.95) or re-intervention rate (3 [2.33%] vs. 20 [7.04%], P = 0.29) was observed between two groups. CTAG group have a lower incidence rate of distal stent graft-induced new entry tear than Valiant Captivia group (2.33% vs. 9.86%, P = 0.045). Lower incidence of type Ia endoleak was identified in the CTAG group (2.22%) than the Valiant Captivia group (14.41%) in patients with type III arch (P = 0.039). CONCLUSIONS: Both Valiant Captivia thoracic stent graft and CTAG thoracic endoprosthesis can be safely performed for acute TBAD with low operative mortality, favorable mid-term survival and freedom from reintervention. CTAG thoracic endoprosthesis had fewer dSINE even with larger oversizing and potentially suitable for type III arch with fewer type Ia endoleaks.

Explant of the Aortic Endograft: Today's Solutions, Tomorrow's Problems.

Type 2 endoleaks remain the Achilles heel of abdominal aortic endografting. They drive imaging costs and repeat intervention. We believe that after two endovascular interventions, patients should be considered for either graft explantation or graft salvage through an open abdominal exploration. Graft explantation has been associated with increased morbidity and mortality but remains necessary in the face of non-correctible type 1a endoleaks, graft failure, or graft infection. In the majority of cases AAA expansion due to persistent type 2 endoleak is the culprit. In this situation, open repair, with oversewing of the lumbar or inferior mesenteric arteries, can be accomplished providing the seal zones and component overall zones are adequate. This approach does not require aortic clamping. We provide detailed descriptions and videos to facilitate the surgeon in performing these complex procedures.

Pre-Operative Four Dimensional Flow Sensitive Magnetic Resonance Imaging Assessment of Aortic Side Branches as a Method to Predict Risk of Type II Endoleak Resulting in Sac Enlargement After EVAR.

OBJECTIVE: To predict sac enlargement with type II endoleak (ELII) before endovascular aneurysm repair (EVAR) using four dimensional flow sensitive magnetic resonance imaging (4D flow MRI). METHODS: A single centre retrospective analysis of prospectively collected data was conducted. Patients with an abdominal aortic aneurysm (AAA) who underwent EVAR between 2013 and 2019 were included. Aortic branches occluded pre-EVAR, and patients with endoleaks other than ELII were excluded. The aortic branch diameter, peak flow velocity (PFVe), and amplitude of the dynamics of flow volume (AFV) were measured in each aortic branch pre-EVAR. Total flow volume per minute (TFV/min), defined as the sum of AFV/min, was calculated in each case. According to computed tomography findings one year post-EVAR, the aortic branches and patients were divided into patent vessel and occluded vessel groups and sac expanding and non-expanding groups. PFVe, AFV/min, and TFV/min were analysed via receiver operating characteristic curve analysis. RESULTS: The patent aortic branches pre-EVAR (69 inferior mesenteric arteries [IMAs]; 249 lumbar arteries [LAs]) of 100 patients were included. Patent IMAs (n = 14) and occluded IMAs (n = 55), patent LAs (n = 23) and occluded LAs (n = 226), and expanding (n = 9) and non-expanding (n = 91) groups were compared, respectively. No statistically significant difference was observed in branch diameters (IMA; patent, 2.5 ± 0.8 mm, occluded, 2.5 ± 0.8 mm, p < .78 and LA; patent, 1.5 ± 0.3 mm, occluded, 1.5 ± 0.4 mm, p < .35). PFVe (IMA; patent, 262.6 mm2/sec, occluded, 183.4 mm2/sec and LA; patent, 142.6 mm2/sec, occluded, 47.7 mm2/sec) and AFV/min (IMA; patent, 8.4 mL, occluded, 5.2 mL and LA; patent, 4.2 mL, occluded, 1.4 mL) were higher in the patent vessel group (p < .050). TFV/min was statistically significantly higher in the expanding group (24.1 mL/min) than in the non-expanding group (7.0 mL/min) (p < .010). CONCLUSION: Pre-EVAR haemodynamic analyses using 4D flow MRI were useful to detect aortic branches responsible for ELII and to predict AAA cases with sac enlargement. This analysis suggests a new strategy for pre-EVAR aortic branch embolisation.

Bicolor K-edge spectral photon-counting CT imaging for the diagnosis of thoracic endoleaks: A dynamic phantom study.

PURPOSE: The purpose of this study was to investigate the feasibility of identifying and characterizing the three most common types of endoleaks within a thoracic aorta aneurysm model using bicolor K-edge imaging with a spectral photon-counting computing tomography (SPCCT) system in combination with a biphasic contrast agent injection. MATERIALS AND METHODS: Three types of thoracic endoleaks (type 1, 2 and 3) were created in a dynamic anthropomorphic thoracic aorta phantom. Protocol consisted in an injection of an iodinated contrast material followed 80 seconds after an injection of a gadolinium-based contrast agent (GBCA). The phantom was scanned using a clinical prototype SPCCT during bicolor phase imaging consisting in an early distribution of GBCA and a late distribution of iodine. Conventional and spectral images were reconstructed for differentiating between the contrast agents and measuring their respective attenuation values and concentrations inside and outside the stent graft. RESULTS: Conventional images failed to provide specific dynamic imaging contrast agents in the aneurysmal sac and outside the stent graft while spectral images differentiated their specific distribution. In type 1 and 3 thoracic endoleaks, GBCA concentration was measured outside the stent graft at 6.1 ± 3.7 (standard deviation [SD]) mg/mL and 6.0 ± 4.0 (SD) mg/mL, respectively, in favor of an early blood flow. In type 2 thoracic endoleak, iodine was measured outside the stent graft at 24.3 ± 5.5 (SD) mg/mL in favor of a late blood flow in the aneurysmal sac. CONCLUSION: Bicolor K-edge imaging enabled SPCCT allows a bicolor characterization of thoracic aorta endoleaks in a single acquisition in combination with a biphasic contrast agent injection.

Early- and Mid-Term Results of Abdominal Endovascular Aneurysm Repair Using an Aortic Cuff Prior to the Main Body to Prevent Type II Endoleaks.

PURPOSE: Postoperatively persistent type II endoleaks (T2ELs) in abdominal endovascular aneurysm repair (EVAR) are known risk factors for long-term aneurysm enlargement. Therefore, various measures have been proposed to prevent T2ELs. Notably, the Kilt technique, which can be used in patients with dumbbell-shaped morphology, employs an aortic cuff deployed in the distal seal zone before the main body. Although previous studies have successfully applied this technique for preventing T2ELs, the mid- and long-term outcomes remain unclear. This study aimed to report the early- to mid-term outcomes in cases where an aortic cuff technique was used to prevent T2ELs. MATERIALS AND METHODS: This retrospective single-center study analyzed 9 patients (mean age, 79 years; range, 69-88 years; 8 men) with abdominal aortic aneurysms. All patients underwent EVAR using an aortic cuff to prevent T2ELs. The primary end points were technical success (successful deployment) and clinical success (no T2ELs). Secondary end points included morbidity, reintervention, and aortic remodeling during follow-up. RESULTS: The technical success rate was 100%. There were no intraprocedural or postoperative complications. No deaths or reinterventions occurred. Postoperative computed tomography showed no endoleaks in 6 patients, while T2ELs from the lumbar artery outside the aortic cuff deployment range were noted in 3 patients. However, no T2ELs were observed in the artery in the aortic cuff deployment range in any patient. The average number of successfully occluded arteries was 4.2 (range, 2-8). All patients had follow-up >6 (mean, 18.6; range, 6-36) months. Aneurysm sac shrinkage occurred in 5 patients during the follow-up period, whereas aneurysm size was stable in 3 patients. In contrast, only 1 patient showed transient dilation of the aneurysm sac enlargement; however, this dilation remained unchanged even after 1.5 years. CONCLUSION: The aortic cuff technique is a favorable endovascular method for preventing T2ELs in EVAR. The present study showed that a single aortic cuff could easily and reliably occlude arteries branched from the aneurysm sac.