Treatment Of Abdominal Aortic Aneurysms Research Articles

Reliability of the modified Frailty Index (mFI) for intervention and continued surveillance in elective infrarenal abdominal aortic aneurysm (AAA)

IntroductionFrailty has been proven to lead to higher morbidity and mortality rates in surgical patients, independent of age. The modified Frailty Index (mFI) is a validated means of assessing for frailty. Aim of studyThe aim of this study is to ascertain if the mFI correlates with clinician experience in turning down patients for abdominal aortic aneurysm (AAA) surgery and/or AAA surveillance. MethodsA contemporaneously recorded database of all AAA patients treated during 2017 at a large University Hospital was reviewed. Patients were categorised into the following groups; continued surveillance, turned down for surveillance, patient declined surveillance, patient offered surgery, patient turned down for surgery and patient declined surgery. ResultsOne hundred and forty two patients were included. Twenty-eight patients <5.5 cm were turned down for surveillance with a mFI of 0.27. Forty-one patients <5.5 cm continued with surveillance, with a mFI of 0.09 (p < 0.0001). Eighteen patients >5.5 cm were turned down for surgical intervention with a median mFI of 0.36. Forty-two patients were offered surgical intervention had a median mFI of 0.09 (p < 0.0001). ConclusionFrailty is associated with higher morbidity and mortality amongst frail patient cohorts. mFI is a valid and easy to use tool to predict perioperative outcomes in AAA intervention. It correlates well with senior, experienced clinicians’ decision-making in relation to who should and who should not undergo elective AAA surgery and those patients who should have ongoing aneurysm surveillance.

Gut microbiome sheds light on the development and treatment of abdominal aortic aneurysm.

Abdominal aortic aneurysm (AAA) is an inflammatory vascular disease with high disability and mortality. Its susceptible risk factors include old age, being male, smoking, hypertension, and aortic atherosclerosis. With the improvement of screening techniques, AAA incidence and number of deaths caused by aneurysm rupture increase annually, attracting much clinical attention. Due to the lack of non-invasive treatment, early detection and development of novel treatment of AAA is an urgent clinical concern. The pathophysiology and progression of AAA are characterized by inflammatory destruction. The gut microbiota is an "invisible organ" that directly or indirectly affects the vascular wall inflammatory cell infiltration manifested with enhanced arterial wall gut microbiota and metabolites, which plays an important role in the formation and progression of AAA. As such, the gut microbiome may become an important risk factor for AAA. This review summarizes the direct and indirect effects of the gut microbiome on the pathogenesis of AAA and highlights the gut microbiome-mediated inflammatory responses and discoveries of relevant therapeutic targets that may help manage the development and rupture of AAA.

Nuclear Receptor NR1D1 Regulates Abdominal Aortic Aneurysm Development by Targeting the Mitochondrial Tricarboxylic Acid Cycle Enzyme Aconitase-2.

Metabolic disorder increases the risk of abdominal aortic aneurysm (AAA). NRs (nuclear receptors) have been increasingly recognized as important regulators of cell metabolism. However, the role of NRs in AAA development remains largely unknown. We analyzed the expression profile of the NR superfamily in AAA tissues and identified NR1D1 (NR subfamily 1 group D member 1) as the most highly upregulated NR in AAA tissues. To examine the role of NR1D1 in AAA formation, we used vascular smooth muscle cell (VSMC)-specific, endothelial cell-specific, and myeloid cell-specific conditional Nr1d1 knockout mice in both AngII (angiotensin II)- and CaPO4-induced AAA models. Nr1d1 gene expression exhibited the highest fold change among all 49 NRs in AAA tissues, and NR1D1 protein was upregulated in both human and murine VSMCs from AAA tissues. The knockout of Nr1d1 in VSMCs but not endothelial cells and myeloid cells inhibited AAA formation in both AngII- and CaPO4-induced AAA models. Mechanistic studies identified ACO2 (aconitase-2), a key enzyme of the mitochondrial tricarboxylic acid cycle, as a direct target trans-repressed by NR1D1 that mediated the regulatory effects of NR1D1 on mitochondrial metabolism. NR1D1 deficiency restored the ACO2 dysregulation and mitochondrial dysfunction at the early stage of AngII infusion before AAA formation. Supplementation with αKG (α-ketoglutarate, a downstream metabolite of ACO2) was beneficial in preventing and treating AAA in mice in a manner that required NR1D1 in VSMCs. Our data define a previously unrecognized role of nuclear receptor NR1D1 in AAA pathogenesis and an undescribed NR1D1-ACO2 axis involved in regulating mitochondrial metabolism in VSMCs. It is important that our findings suggest αKG supplementation as an effective therapeutic approach for AAA treatment.

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.

Snare Guiding Technique in Bifurcated Endovascular Repair of Abdominal Aortic Aneurysm with Severely Tortuous Iliac Artery Access: A Case Report

Endovascular aneurysm repair (EVAR) has gained acceptance as a viable alternative to open surgical treatment for abdominal aortic aneurysm (AAA). We report the use of snare guiding wire in bifurcated EVAR case with severely tortuous femoral access. A 63-year-old man referred to the hospital from another facility with complaints of pulsating mass in right iliac and umbilical region for the last 2 years. He was then admitted to the cardiac catheterization lab for EVAR under general anaesthetic. Endovascular aneurysm repair (EVAR), also known as an endoprosthesis, is a stent-graft device-guided therapy for a AAA. This procedure is a safer choice for individuals who are elderly or have pulmonary, cardiac, or renal problems. Tortuous iliac arteries might obstruct device delivery during EVAR. The Snare Guiding Wire approach might be an alternate method for EVAR to treat AAA if conventional cannulation is difficult or impossible in individuals with highly tortuous iliac access.

Systematic Review and Meta-analysis of Physician Modified Endografts for Treatment of Thoraco-Abdominal and Complex Abdominal Aortic Aneurysms

Systematic Review and Meta-analysis of Physician Modified Endografts for Treatment of Thoraco-Abdominal and Complex Abdominal Aortic Aneurysms

Abdominal compartment syndrome after endovascular repair of ruptured abdominal aortic aneurysm: A case report and literature review

Background: Abdominal compartment syndrome (ACS) arises in approximately 7% after ruptured abdominal aortic aneurysm (RAAA) treatment. Decompressive laparotomy is a satisfactory way to treat ACS. The problem is deciding when to complete abdominal closure with appropriate alternative treatments.[1]&#x0D; Methods: This is a case report of successful ACS treatment following RAAA intervention at Ho Chi Minh University Hospital of Medicine and Pharmacy with a literature review.&#x0D; Clinical case: A 61-year-old male patient was hospitalized for abdominal pain. Computed tomography angiography demonstrated RAAA. He underwent the emergency endovascular repair of ruptured aneurysms (rEVAR). At 30 minutes post-intervention, the patient's abdomen was distended following intraabdominal hypertension measured via bladder catheter. Within ACS diagnosing, emergency decompressive laparoscopy was performed. The abdominal wall was left open and covered with a sterile nylon cover. The fascial closure was performed on the sixth postoperative day with the support of vacuum-assisted wound closure (VAC) and mesh-mediated fascial traction. On the 27th postoperative day, the wound could close completely, and the patient could be discharged successfully.&#x0D; Conclusion: A bladder pressure is required to monitor intraabdominal pressure postoperatively after decompressive laparotomy. Delayed fascial closure is appropriate with supporting VAC until total abdominal closure.

Effects of abdominal aortic aneurysm appropriateness dashboard on clinical practice

ObjectiveThe Society for Vascular Surgery published abdominal aortic aneurysm (AAA) practice guidelines in 2003, 2009, and 2018 to improve the management and treatment of AAAs. In 2014, our vascular surgery department implemented a quarterly AAA dashboard (AAAdb) to record the perioperative outcomes and guideline compliance with a focus on intervention appropriateness and procedural follow-up, which supplemented our Vascular Quality Initiative data. From the available reported evidence and expert consensus opinions, nine additional criteria for the appropriate treatment of AAAs <5 cm in women and <5.5 cm in men were noted, when applicable. The purpose of our study was to assess the effects of AAAdb implementation on adherence to society and institutional guidelines, documentation of treatment rationale, and the quality of follow-up. MethodsWe performed a retrospective review of elective open and endovascular AAA repair at a single institution from 2010 to 2018. The AAAdb was implemented in the middle of this period in 2014. The patient demographics, aortic size, repair indication, repair type, 30-day mortality, and postoperative and 1-year follow-up imaging findings were analyzed. The primary outcome was adherence to intervention appropriateness and the follow-up guidelines. The categorical factors were summarized using frequencies and percentages and compared using the Pearson χ2 test or Fisher exact test. Continuous measures were summarized using the mean ± standard deviation and compared between study periods using two-sample t tests. ResultsFrom 2010 to 2018, 1549 patients had undergone elective AAA repair: 657 before and 892 after AAAdb implementation. No differences were found in AAA size after AAAdb (5.6 ± 1.2 cm vs 5.6 ± 1.1 cm; P = .88). However, the proportion of size-appropriate repairs increased (64.1% vs 71.3%; P = .003). The proportion of small AAA repairs with a documented rationale had increased (64.4% vs 80.5%; P < .001), with rapid disease progression cited most often. No difference was found in 30-day mortality (1.2% vs 1.5%; P = .69). Follow-up imaging after endovascular abdominal aortic aneurysm repair increased at <60 days postoperatively (76% vs 84%; P = .004) and at 1 year of follow-up (78% vs 86%; P = .0005). The proportion of patients with endoleak at <60 days postoperatively had increased in the post-AAAdb cohort (21% vs 29%; P = .012). ConclusionsThe AAAdb served as a centerpiece for improving the appropriateness of care and compliance with national and institutional guidelines, including treatment of small AAAs in special circumstances. Its implementation was associated with higher quality follow-up and surveillance in a high-volume, regional aortic center. Consideration should be given to adding additional criteria to the Society for Vascular Surgery guidelines and Vascular Quality Initiative reporting.

Through network pharmacology and molecular docking to explore the underlying mechanism of Artemisia annua L. treating in abdominal aortic aneurysm.

Background: Abdominal aortic aneurysm (AAA) is a degenerative disease that causes health problems in humans. However, there are no effective drugs for the treatment of AAA. Artemisia annua L. (A. annua) is a traditional herbal that has been widely used in cardiovascular disease. Based on network pharmacology and molecular docking technology, this study predicted the practical components and potential mechanisms of A. annua inhibiting the occurrence and development of AAA. Methods: The main active ingredients and targets of A. annua were screened through the TCMSP database; the GeneCards, OMIM, PharmGkb, and TTD databases were used to search for the targeted genes of AAA and map them to the targets of the active ingredients to obtain the active ingredient therapy of A. annua. The targets of AAA were to construct a protein interaction network through the STRING platform. R software was used to carry out the enrichment analysis of GO and KEGG for relevant targets, and Cytoscape was used to construct the active ingredient-target network prediction model of A. annua. Finally, AutoDock Vina was used to verify the results of the active ingredients and critical targets. Results: The main active ingredients obtained from A. annua for the treatment of AAA include quercetin, luteolin, kaempferol, isorhamnetin, and artemetin, as well as 117 effective targets, including RELA, MAPK14, CCND1, MAPK1, AKT1, MYC, MAPK8, TP53, ESR1, FOS, and JUN. The 11 targeted genes might play a key role in disease treatment. Enriched in 2115 GO biological processes, 159 molecular functions, 56 cellular components, and 156 KEGG pathways, inferred that its mechanism of action might be related to PI3K-Akt signaling pathway, fluid shear stress, atherosclerosis, and AGE-RAGE signaling pathway. Molecular docking results showed that the top five active components of A. annua had a good affinity for core disease targets and played a central role in treating AAA. The low binding energy molecular docking results provided valuable information for the development of drugs to treat AAA. Conclusion: Therefore, A. annua may have multiple components, multiple targets, and multiple signaling pathways to play a role in treating AAA. A. annua may have the potential to treat AAA.

OC-057 PREVENTION OF INCISIONAL HERNIAS BY PROPHYLACTIC MESH-AUGMENTED REINFORCEMENT OF MIDLINE LAPAROTOMIES FOR ABDOMINAL AORTIC ANEURYSM TREATMENT. 5-YEAR FOLLOW-UP OF A RANDOMIZED CONTROLLED TRIAL

Abstract Introduction The incidence of incisional hernias (IHs) after open repair of an abdominal aortic aneurysm (AAA) is high. Several randomized controlled trials have reported favorable results with the use of prophylactic mesh to prevent IHs, without increasing complications. In this analysis we report on the results of the 60-month follow-up of the PRIMAAT trial (Ann Surg 2016; 263(4): 638–45). Methods In a prospective, multicenter, open label, randomized design, patients were randomized between prophylactic retrorectus mesh reinforcement (MESH group), and primary closure of their midline laparotomy after open AAA repair (NOMESH group). This article reports on the results of clinical follow-up after 60 months. If performed, ultrasonography or computed tomography were used for the diagnosis of IHs. Results Of the 120 randomized patients, 114 were included in the intention-to-treat analysis. Thirty-three patients in the NOMESH group (33/58–56.9%) and 34 patients in the MESH group (34/56–60.7%) were evaluated after 5 years. The cumulative incidence of IHs in the NOMESH group was 32.9% after 24 months and 49.2% after 60 months. No incisional hernias were diagnosed in the MESH group. In the NOMESH group, 21.7% (5/23) underwent reoperation within 5 years due to an IH. Conclusion Prophylactic retrorectus mesh reinforcement after midline laparotomy for the treatment of AAAs safely and effectively decreases the rate of IHs. The cumulative incidence of IHs after open AAA repair, when no mesh is used, continues to increase during the first 5 years after surgery, which leads to a substantial rate of hernia repairs.

A prospective, multicenter, single-arm clinical trial cohort to evaluate the safety and effectiveness of a novel stent graft system (WeFlow-JAAA) for the treatment of juxtarenal abdominal aortic aneurysm: A study protocol.

IntroductionJuxtarenal abdominal aortic aneurysms (JRAAAs) are challenging to cure by traditional endovascular aortic repair (EVAR). Due to the inherent disadvantages of the customized fenestrated and/or branched aortic endografts (such as delayed cycles with a risk of aneurysm rupture, unavailable in emergency or confine operations), several off-the-shelf devices have been developed for the treatment of JRAAA. However, these devices being used in clinical trials have been proven to have a non-negligible risk of reintervention and inadequate anatomic applicability. We have developed a new off-the-shelf aortic endograft system (WeFlow-JAAA) with a mixed design of inner branches and modified fenestrations. The purpose of this cohort study is to assess the safety and effectiveness of the innovative aortic endograft system.Methods and analysisThis is a prospective, multicenter, single-armed clinical trial cohort study. The enrolment will take place in 29 centers in China, and 106 adult patients with JRAAA will be enrolled in total. Clinical information and CT angiography (CTA) images will be collected and recorded. Patients will be followed up for 5 years. The primary safety endpoint is the rate of no major adverse event within 30 days after index EVAR. The primary efficacy endpoint is the rate of immediate technical success and no JRAAA-related reintervention within 12 months after the procedure.

Correlative effect between sac regression and patient longevity following endovascular solution for abdominal aortic aneurysms: an international analysis.

Since the introduction of endovascular aortic repair (EVAR) it has become the mainstay treatment for abdominal aortic aneurysms. Several EVAR devices exist commercially, yet, the Terumo Aortic Fenestrated Anaconda™ endograft has demonstrated outstanding results. Evidence in the literature suggests that sac regression could be linked to patient survival and longevity. The main scope of this study is to evaluate sac regression and survival achieved using the Fenestrated Anaconda™ endograft and to discuss relevant literature. The current study represents a nine-year cross-sectional international analysis of custom-made Fenestrated Anaconda™ device. For the statistical analysis, SPSS 28 for Windows and R were utilised. Pearson chi-square analysis was used to assess differences in cumulative distribution frequencies between select variables. Statistical significance for all two-tailed tests was set at p < 0.05. A total of 5,058 patients received the Fenestrated Anaconda™ in this study, either due to unsuitable/complex anatomy for competitor devices (n = 3,891) or based on surgeon preference (n = 1,167). A sac regression of 0-30% was observed in 4,772 (94.3%) over the first four years post-EVAR. Here, 99.6% of patients receiving the Fenestrated Anaconda™ due to unsuitable/complex anatomy for competitor devices and 76.8% based on surgeon preference had 0-30% sac regression. During years 5-9 of follow-up, all patients had 20-45% sac regression. Patient survival during the first six years post-EVAR was 100% but dropped to 77.1% in years 7-9. Survival differed between categorical patient subsets based on the indication. The Fenestrated Anaconda™ has been proven to be a highly effective EVAR endograft. Evidence in the literature clearly demonstrates that sac regression is an accurate prognostic factor for patient survival and longevity.

Endovascular aneurysm repair offers a survival advantage and is cost-effective compared with conservative management in patients physiologically unfit for open repair

ObjectiveThe endovascular aneurysm repair-2 (EVAR-2) trial suggested that EVAR in patients unfit for open surgical repair (OSR) failed to provide a significant overall survival advantage compared with conservative management. The aim is to compare survival and cost-effectiveness in patients with poor cardiopulmonary exercise test (CPET) metrics who underwent EVAR or were managed conservatively. MethodsA prospective database of all CPETs (1435 patients) performed to assess preoperative fitness for abdominal aortic aneurysm repair was maintained. A total of 350 patients deemed unfit for OSR underwent EVAR or were managed conservatively. A 1:1 propensity-matched analysis incorporating age, gender, anaerobic threshold, and aneurysm size was used to compare survival. Cost-effectiveness analysis was based on the economic model for the National Institute for Health and Care Excellence clinical guideline on abdominal aortic aneurysm treatment. ResultsPropensity matching produced 122 pairs of patients in the EVAR and conservative management groups. The median overall survival for the EVAR group was significantly longer than that for the conservative management group (84 vs 30 months, P < .001). One-, three-, and five-year mortality in the EVAR group was 7%, 40%, and 68%, respectively, compared with 25%, 68%, and 82% in the conservative management group, all P < .001. The increment cost-effectiveness ratio for EVAR was £8023 (US$11,644) per quality-adjusted life year gained compared with £430,602 (US$624,967) in the National Institute for Health and Care Excellence guideline, which is based on EVAR-2 results. ConclusionsEVAR offers a survival advantage and is cost-effective in selected patients deemed unfit for OSR based on CPET compared with conservative management.

Vascular Quality Initiative Assessment of Compliance with Society for Vascular Surgery Clinical Practice Guidelines on the Management of Extracranial Cerebrovascular Disease

Compliance with Society for Vascular Surgery (SVS) clinical practice guidelines (CPGs) is associated with improved outcomes for treatment of abdominal aortic aneurysm, but has not been assessed for carotid artery disease. The Vascular Quality Initiative (VQI) registry was used to examine compliance with the SVS CPGs for management of extracranial cerebrovascular disease and its impact on outcomes.

The continued need for infrarenal sealing endovascular aneurysm repair devices

Treatment of abdominal aortic aneurysms (AAA) has evolved from being a relatively high-risk surgical operation to a minimally invasive percutaneous endovascular procedure in 2022. The development of endovascular devices specific to this purpose represents remarkable achievement in the evolutionary treatment of vascular diseases and has transformed a deadly disease into a more manageable medical condition. The report of the W. L Gore Excluder Conformable (EXCC) US regulatory trial reflects the latest generation of endovascular aneurysm repair (EVAR) devices.

Early Institutional Experience with One-Piece Bifurcated-Fenestrated Stentgraft in the Treatment of Abdominal Aortic Aneurysms

Purpose: To review the early experience of the use of a bifurcated-fenestrated endograft (Bif-FEVAR) to treat abdominal aortic aneurysms (AAA) in a high-volume aortic center. Methods: A retrospective single-center analysis was conducted between March 2019 and April 2021 including consecutive patients that underwent Bif-FEVAR. Only patients without a proper infrarenal neck and a distance <70 mm between the lowest target artery and the native or prosthetic aortic bifurcation were considered. All Bif-FEVAR custom-made devices were manufactured by Cook Medical (Inc., Bloomington, Indiana). Demographics, anatomical features, technical success, major adverse events, 30-day mortality, and survival according to Kaplan–Meier were analyzed according to Society for Vascular Surgery standards. Results: Overall, 10 patients (100% male with median age 78) were included. The median preoperative maximal aneurysm diameter was 68 mm [51–84]. Eight patients were treated for a proximal type I endoleak after endovascular aneurysm repair. A total of 36 fenestrations were planned. The median operative time was 144 min [127–168], with a median fluoro time of 40.5 min [34–54] and a median dose area product of 73 Gy cm2 [61–89]. Technical success rate was 100%. No patients experienced a major postoperative adverse event. Median follow-up time was 8 months [6–13]. Conclusion: Bif-FEVAR is technically feasible when there is a short distance below the lowest target artery and the aortic bifurcation, with favorable short-term results. Clinical Impact This study assessed the use of an innovative one-piece bifurcated fenestrated stent-graft as a primary procedure or in the treatment of proximal endoleak after standard infrarenal EVAR. We demonstrated these custom-made devices can be used safely with favorable short-term results. One-piece bifurcated fenestrated stent-grafts extend the indications of FEVAR for patients with an unusually short distance between the lowest renal artery and the aorto-iliac bifurcation or the diverter flow of a preexisting bifurcated infrarenal stent-graft.

The role and mechanism of epidermal growth factor receptor in hemodynamic induction of abdominal aortic aneurysm formation.

BackgroundAbdominal aortic aneurysm (AAA) is a serious threat to human health, and in the event of aneurysm rupture, the rates of disability and mortality are high. At present, the treatment of AAA mainly includes craniotomy and endovascular therapy. With advances in technology, although the safety of the treatment is improving, there is still a risk associated with surgery. Therefore, the exploration of non-invasive treatment options for aneurysms is worthwhile. The etiology of aneurysms must be investigated to identify the target of non-invasive treatment.MethodsIn the experimental group, bilateral common carotid arteries were ligated, while in the control group, bilateral common carotid arteries were exposed. After 5 days, the rabbits were sacrificed, and the hearts were perfused with normal saline. Smooth muscle cells (SMCs) of abdominal aorta were isolated by enzyme digestion. Total RNA was extracted from SMC samples and detected using an Agilent Rabbit 4×44K Gene Expression Microarray. Then, some genes were selected and real-time polymerase chain reaction (RT-PCR) was conducted to verify the credibility of the chip results. Finally, Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were performed. The transcriptome contained in the identified differentially expressed gene (DEG) was analyzed.ResultsMicroarray revealed 947 DEGs, of which 617 genes were increased and 330 genes were decreased in the experimental group compared with the control group. The microchips of PTHLH, ENPP1, IGF1, and others were selected to verify the altered genes by PCR.ConclusionsThe gene expression of rabbit abdominal aorta SMCs was significantly changed under high blood flow load. Through data analysis, it was found that some specific genes and transcription factors may play an important role in hemodynamically-induced vascular remodeling.

MicroRNA–disease Network Analysis Repurposes Methotrexate for the Treatment of Abdominal Aortic Aneurysm in Mice

Abdominal aortic aneurysm (AAA) is a permanent dilatation of the abdominal aorta and is highly lethal. The main purpose of the current study is to search for noninvasive medical therapies for AAA, for which there is currently no effective drug therapy. Network medicine represents a cutting-edge technology, as analysis and modeling of disease networks can provide critical clues regarding the etiology of specific diseases and therapeutics that may be effective. Here, we proposed a novel algorithm to quantify disease relations based on a large accumulated microRNA–disease association dataset and then built a disease network covering 15 disease classes and 304 diseases. Analysis revealed some patterns for these diseases. For instance, diseases tended to be clustered and coherent in the network. Surprisingly, we found that AAA showed the strongest similarity with rheumatoid arthritis and systemic lupus erythematosus, both of which are autoimmune diseases, suggesting that AAA could be one type of autoimmune diseases in etiology. Based on this observation, we further hypothesized that drugs for autoimmune diseases could be repurposed for the prevention and therapy of AAA. Finally, animal experiments confirmed that methotrexate, a drug for autoimmune diseases, was able to alleviate the formation and development of AAA.

Artificial intelligence assisted compositional analyses of human abdominal aortic aneurysms ex vivo.

Quantification of histological information from excised human abdominal aortic aneurysm (AAA) specimens may provide essential information on the degree of infiltration of inflammatory cells in different regions of the AAA. Such information will support mechanistic insight in AAA pathology and can be linked to clinical measures for further development of AAA treatment regimens. We hypothesize that artificial intelligence can support high throughput analyses of histological sections of excised human AAA. We present an analysis framework based on supervised machine learning. We used TensorFlow and QuPath to determine the overall architecture of the AAA: thrombus, arterial wall, and adventitial loose connective tissue. Within the wall and adventitial zones, the content of collagen, elastin, and specific inflammatory cells was quantified. A deep neural network (DNN) was trained on manually annotated, Weigert stained, tissue sections (14 patients) and validated on images from two other patients. Finally, we applied the method on 95 new patient samples. The DNN was able to segment the sections according to the overall wall architecture with Jaccard coefficients after 65 epocs of 92% for the training and 88% for the validation data set, respectively. Precision and recall both reached 92%. The zone areas were highly variable between patients, as were the outputs on total cell count and elastin/collagen fiber content. The number of specific cells or stained area per zone was deterministically determined. However, combining the masks based on the Weigert stainings, with images of immunostained serial sections requires addition of landmark recognition to the analysis path. The combination of digital pathology, the DNN we developed, and landmark registration will provide a strong tool for future analyses of the histology of excised human AAA. In combination with biomechanical testing and microstructurally motivated mathematical models of AAA remodeling, the method has the potential to be a strong tool to provide mechanistic insight in the disease. In combination with each patients’ demographic and clinical profile, the method can be an interesting tool to in supportof a better treatment regime for the patients.

Type 2 endoleak embolization and utilization of non-contrast-enhanced magnetic resonance angiography (NCE-MRA) as a non-invasive imaging follow-up method.

Endovascular aneurysm repair (EVAR) is a minimally invasive technique widely used in abdominal aortic aneurysm treatment. The most common complications after EVAR remain endoleaks, type 2 endoleak (T2EL) being the most prevalent. T2EL detection and surveillance require imaging techniques such as computed tomography angiography (CTA), contrast-enhanced magnetic resonance angiography (CE-MRA), Doppler ultrasound, or digital subtraction angiography (DSA). However, these modalities are associated with numerous limitations, including exposure to ionizing radiation, contrast media administration, or operator dependency, as in the case of ultrasonography. A non-contrast-enhanced MRA could be a substitute non-invasive method for endoleak monitoring. Our case report describes an 83-year-old female patient with type 2 endoleak and enlarging aneurysm sac detected on a CT scan. Despite the enormous aneurysm size, the patient underwent endovascular treatment owing to multiple comorbidities. Due to challenging feeding vessel anatomy, catheterization of the aneurysmal sac was impossible. Attempted polymerization of the aneurysmal sac with Glubran-2 partially sealed the sac and obliterated the feeders' inflow. Unfortunately, a non-targeted embolization resulted in the loss of patency of the right feeder and adjacent communicating branch. The patient underwent follow-up imaging that included non-contrast-enhanced as well as contrast-enhanced MRA. The examination revealed the presence of a small residual endoleak, a freshly formed thrombus, and areas of old thrombi. The NCE-MR appeared to be a valuable tool in endoleak detection and provided a detailed clot morphology.