Enabling extracorporeal ultrasound imaging with the da Vinci robot for transoral robotic surgery: a feasibility study.

PURPOSE: Transoral robotic surgery (TORS) is a challenging procedure due to its small workspace and complex anatomy. Ultrasound (US) image guidance has the potential to improve surgical outcomes, but an appropriate method for US probe manipulation has not been defined. This study evaluates using an additional robotic (4th) arm on the da Vinci Surgical System to perform extracorporeal US scanning for image guidance in TORS. METHODS: A stereoscopic imaging system and da Vinci-compatible US probe attachment were developed to enable control of the extracorporeal US probe from the surgeon console. The prototype was compared to freehand US by nine operators in three tasks on a healthy volunteer: (1) identification of the common carotid artery, (2) carotid artery scanning, and (3) identification of the submandibular gland. Operator workload and user experience were evaluated using a questionnaire. RESULTS: The robotic US tasks took longer than freehand US tasks (2.09x longer; p = 0.001 ) and had higher operator workload (2.12x higher; p = 0.004 ). However, operator-rated performance was closer (avg robotic/avg freehand = 0.66; p = 0.017 ), and scanning performance measured by MRI-US average Hausdorff distance provided no statistically significant difference. CONCLUSION: Extracorporeal US scanning for intraoperative US image guidance is a convenient approach for providing the surgeon direct control over the US image plane during TORS, with little modification to the existing operating room workflow. Although more time-consuming and higher operator workload, several methods have been identified to address these limitations.

A hybrid approach to complex bilateral common iliac artery and internal iliac artery aneurysm repair.

A case of a young patient with incidental bilateral internal iliac artery aneurysms and common iliac artery aneurysms is described. A staged hybrid surgical approach was performed to preserve pelvic perfusion, with bilateral stent grafts deployed into an ipsilateral anterior division branch and contralateral posterior division branch of the internal iliac arteries. One week later, an open infrarenal aorto-bi-iliac graft was performed with distal anastomoses to the previously deployed stent grafts. The findings from the present case add to the growing number of reported cases of hybrid repair of bilateral internal iliac and common iliac artery aneurysms with preservation of pelvic perfusion.

Aortic arch endovascular branch and fenestrated repair: Initial Canadian experience with novel technology.

Objective: The objective is to describe the initial Canadian experience using novel aortic arch branched endograft technologies. Methods: We performed a retrospective consecutive case series of all patients undergoing aortic arch branched repair with newly available endograft technology since 2020 at our site. We describe the patient characteristics, treatment characteristics, and postoperative outcomes. Results: Eleven patients received arch branched endografts, indicated for penetrating aortic ulcer in seven patients (64%), arch degeneration after prior aortic dissection repair in three (27%), and acute aortobronchial fistula in one patient (9%). Their average age was 72 ± 7 years. Complete arch repair from zone 0 to 4 was performed in six cases (55%); the remaining repairs landed proximally in zones 1 or 2. Seven repairs used a single retrograde facing inner branch (thoracic branch endoprosthesis; W.L. Gore & Associates), three used double antegrade inner branch (Bolton Relay; Terumo Interventional Systems), and one emergent case used double in situ fenestrations. Seven repairs (64%) used an adjunctive extra-anatomic bypass to complete great vessel perfusion, two of which were created during a prior aortic repair. Inferior vena cava balloon inflow occlusion during deployment was used in all cases. No mortalities, transient or permanent spinal cord paralysis, myocardial infarction, dialysis dependence, venous thromboembolism, or bleeding requiring reintervention occurred. No patient undergoing elective arch branch repair experienced a stroke. The one patient undergoing emergent repair did suffer a stroke. The median length of stay was 5 days (interquartile range, 2-8 days). Two endoleaks developed: a type Ia endoleak successfully treated with a Palmaz stent (Cordis) during the index admission, and a type II endoleak with ongoing sac regression on postoperative follow-up. Postoperatively, one patient suffered a suspected aortic graft infection that was treated with lifelong antibiotics. During a mean radiographic follow-up of 7.2 months, no cases of branch vessel instability (ie, no migration, reintervention, arterial rupture, intraluminal thrombus, occlusion, stenosis, or kinking of the branch grafts) developed. Three patients experienced sac regression of >5 mm, and no patient experienced continued postoperative dilation. Conclusions: To the best of our knowledge, this is the largest reported Canadian volume of aortic arch repair using novel branched or fenestrated technology. The series demonstrates that a multidisciplinary program and properly selected patients can yield excellent results using endovascular repair for complex aortic arch pathology.

Characterizing the impact of Enterococcus cecorum infection during late embryogenesis on disease progression, cecal microbiome composition, and early performance in broiler chickens.

Enterococcus cecorum (EC) has been associated with septicemia and early mortality in broiler chickens. There is limited research investigating the pathogenicity of EC field strains obtained from affected birds. The purpose of this study was to evaluate the effect of in-ovo administration into the amnion with different EC field isolates at d 18 of embryogenesis (DOE18). In Exp 1, 7 EC field isolates alone or in combination (EC1-EC3, EC4-EC5, EC6, and EC7) were selected based on phenotypic characteristics and evaluated at different concentrations (1 × 102, 1 × 104, and 1 × 106 CFU/200 µL/embryo) to assess the impact on early performance and macroscopic lesions. Three isolates (n = 3; EC2, EC5, EC7) were selected for additional evaluation based on the significant (P < 0.05) BWG reduction (d 0-21) compared to the negative control (NC) and the presence of macroscopic lesions observed during posting sessions at d 14 and d 21. An additional isolate associated with enterococcal spondylitis was included in Exp 2 (EC11B). Treatment groups for Exp 2 include: 1) NC, 2) EC2, 3) EC5, 4) EC7, and 5) EC11B (n = 90-120/embryos/group). Groups 2 to 5 were challenged at 1 × 102 CFU/200 µL/embryo by in-ovo injection into the amnion at DOE18. Chicks were placed in battery cages for the duration of the study (21 d), and pen weights were recorded at d 0, d 7, d 14, and d 21 to calculate average BW and BWG. At d 14 and d 21 posthatch, liver, spleen, free thoracic vertebrae (FTV), and femoral head (FH) were aseptically collected to enumerate Enterococcus spp. using Chromagar Orientation as the selective media. Cecal contents were collected at d 21 to evaluate the effect of EC challenge on the cecal microbiome composition. There was a significant (P < 0.05) reduction in BW at d 21, and BWG from d 14 to 21 and d 0 to 21, for EC7 and EC11B. Enterococcus cecorum was recovered from the FTV of all challenged groups at d 14 and d 21. The most representative lesions were pericarditis, hydropericardium, focal heart necrosis, and FH osteomyelitis. However, lesions were not uniform across challenged groups or ages (d 14 and d 21). Alpha diversity of the cecal contents was markedly lower in EC5 and EC11B compared to all treatment groups suggesting that EC exposure during late embryogenesis affect the cecal microbiome up to 21 d posthatch. Additionally, these results highlight the differences in pathogenicity of EC strains isolated from field cases and suggest that hatchery exposure to EC during late embryogenesis is a potential route of introduction into a flock.

AI-powered assessment of biomarkers for growth prediction of abdominal aortic aneurysms.

Objective: The purpose of this study was to employ biomechanics-based biomarkers to locally characterize abdominal aortic aneurysm (AAA) tissue and investigate their relation to local aortic growth by means of an artificial intelligence model. Methods: The study focused on a population of 36 patients with AAAs undergoing serial monitoring with electrocardiogram-gated multiphase computed tomography angiography acquisitions. The geometries of the aortic lumen and wall were reconstructed from the baseline scans and used for the baseline assessment of regional aortic weakness with three functional biomarkers, time-averaged wall-shear stress, in vivo principal strain, and intra-luminal thrombus thickness. The biomarkers were encoded as regional averages on axial and circumferential sections perpendicularly to the aortic centerline. Local diametric growth was obtained as difference in diameter between baseline and follow-up at the level of each axial section. An artificial intelligence model was developed to predict accelerated aneurysmal growth with the Extra Trees algorithm used as a binary classifier where the positive class represented regions that grew more than 2.5 mm/year. Additional clinical biomarkers, such as maximum aortic diameter at baseline, were also investigated as predictors of growth. Results: The area under the curve for the constructed receiver operating characteristic curve for the Extra Trees classifier showed a very good performance in predicting relevant aortic growth (area under the curve = 0.92), with the three biomechanics-based functional biomarkers being objectively selected as the main predictors of growth. Conclusions: The use of features based on the functional and local characterization of the aortic tissue resulted in a superior performance in terms of growth prediction when compared with models based on geometrical assessments. With rapid growth linked to increasing risk for patients with AAAs, the ability to access functional information related to tissue weakening and disease progression at baseline has the potential to support early clinical decisions and improve disease management.

Mortality and risk factors for ruptured abdominal aortic aneurysm after repair endovascular (rARE).

Objective: The aim of this study was to characterize risk factors for infrarenal abdominal aortic aneurysm rupture after endovascular repair (rARE) and evaluate 30-day mortality in comparison to primary ruptured abdominal aortic aneurysm (rAAA). Methods: A retrospective review of all adult patients with rAAA at a single tertiary university care center between February 11, 2006, and December 31, 2018, was performed. A total of 267 patients with rAAA were identified, 11 of whom had rARE. Descriptive statistics were applied due to the small sample size. Results: Overall 30-day mortality was similar between primary rAAA and rARE (31.5% vs 27.3%); however, patients with rARE were more likely to receive palliative care (3.9% vs 18.2%). Mortality of patients who underwent operative intervention was 11.1% for rARE and 28.7% for primary rAAA at 30 days. All patients had an endoleak at the time of rupture. Type 1 and type 3 endoleaks resulting in direct aortic sac pressurization were the primary cause of rARE (9 of 11 patients); however, rupture occurred in two patients with only a type 2 endoleak. There was no sac expansion at the time of rupture in four of 11 patients with rARE. Four of 11 patients were lost to follow-up prior to rARE. Conclusions: rARE is an uncommon complication following EVAR and contributes to late aneurysm-related mortality following endovascular repair. Although the 30-day mortality rate was similar for rARE and primary rAAA, larger series are required to determine which patients with rARE will benefit from intervention. The presence of endoleak and sac expansion may alert surgeons to increased risk of rARE; however, a subset of patients with rARE did not have sac expansion or surveillance imaging on follow-up. Loss to lifelong imaging surveillance remains a risk factor for rARE.

Curriculum Mapping Post-Baccalaureate Registered Nurse Residency Curriculum to Accrediting Agency Standards.

This article examines the process of mapping a post-baccalaureate registered nurse residency curriculum with Commission on Collegiate Nursing Education standards for nurse residencies. Curriculum mapping revealed gaps and redundancies in the curriculum as well as documented compliance with accreditation standards. Curriculum mapping is instrumental to developing, evaluating, and refining curricular elements. Mapping curriculum with accreditation standards simultaneously fulfills accreditation requirements and can increase confidence in readiness within organizations undergoing accreditation site visits.

A Systematic Review of Total Endovascular Aortic Arch Repair: A Promising Technology.

BACKGROUND: Total endovascular aortic arch repair (TEAAR) represents an emerging alternative for the treatment of aortic arch disease in patients at prohibitive risk for open surgery. A systematic review of TEAAR was performed to delineate early outcomes with this new technology. METHODS: All studies (excluding single-patient case reports) of CE-certified "custom made" or "off-the-shelf" zone 0 stent graft deployments were included. The primary search of Medline, Embase, CINAHL, and the Cochrane CENTRAL registry was supplemented with searches of Web of Science, ClinicalTrials.gov, and conference abstracts (within last 3 years), and a hand search of citations within relevant articles. Articles underwent 2-stage screening by 2 independent reviewers before inclusion. RESULTS: Fifteen relevant investigations were identified. Indications for TEAAR were chronic arch dissection with degenerative aneurysmal disease (54%, 148/273), pure arch aneurysm (41%, 112/273), penetrating atherosclerotic ulcer (2%, 5/273), and type IA endoleak from a zone 2 thoracic endograft (1%, 3/273). Double-branch (70%, 192/273), triple-branch (19%, 53/273), and single-branch (into innominate artery; 10%, 28/273) devices were used. Adjunct left carotid-subclavian bypass occurred in 90% of double- and single-branch procedures. Procedural success with TEAAR was 93% (95% CI 85.8%-96.3%). The proportion of all-cause mortality was 16% (95% CI 8%-26%), stroke 14% (8%-24%), peripheral vascular events 7% (1%-33%), and myocardial infarction 4% (2%-7%). Endoleaks were identified in 13% (7%-25%) of the study population. CONCLUSIONS: TEAAR represents an emerging option for the management of aortic arch disease wth high procedural success rates and acceptable early outcomes in a high-risk patient population.

The Aortic Team Model for the Management of the Distal Arch, Descending Thoracic and Thoracoabdominal Aorta: Appraisal at 3 Years.

BACKGROUND: This study aimed to assess feasibility, logistical challenges, and clinical outcomes associated with the implementation of an Aortic Team model for the management of distal arch, descending thoracic and thoracoabdominal aortic disease. METHODS: An Aortic Team care pathway was implemented in November 2019. Working as a unit, two cardiac surgeons, two vascular surgeons, an interventional radiologist, a cardiologist, and an anesthesiologist collectively determined care decisions via multispecialty presence at an Aortic Clinic. Cardiac and vascular surgeons operated in tandem for open procedures. Interventional radiology participated alongside cardiac and vascular for endovascular procedures. Cardiology aided in medical therapies for heritable and degenerative disease, and had a lead role for genetics and high-risk pregnancy referrals. The model spanned three hospitals. Clinical outcomes at 3 years were assessed. RESULTS: There were 35 descending thoracic and thoracoabdominal surgeries and 77 thoracic endovascular aortic repairs. Endoarch devices were used in 7 cases (Gore Thoracic Branch Endoprosthesis, 4, Terumo RelayBranch, 3) and an endothoracoabdominal device in 4 cases (Cook Zenith t-branch). The Aortic Clinic acquired 456 patients, with yearly increases (54 patients [year 1], 181 patients [year 2], 221 patients [year 3]). For surgery, mortality was 8.6% (3/35), permanent paralysis 5.7% (2/35), stroke 8.6% (3/35), permanent dialysis 0%, and reinterventions 8.6% (3/35). For endovascular cases, mortality was 3.9% (3/77), permanent paralysis 3.9% (3/77), stroke 5.2% (4/77), permanent dialysis 1.3% (1/77), and reinterventions 16.9% (13/77). CONCLUSION: An Aortic Team model is feasible and ensures all treatment options are considered. Conventional open thoracoabdominal procedures showed acceptable outcomes. Endoarch technology shows early promise.

Efficacy of cold renal perfusion protection for open complex aortic aneurysm repair: a meta-analysis.

BACKGROUND: Cold renal perfusion (CRP) with 4°C crystalloid fluids has been described as a method to reduce renal injury during open surgical repair of complex aortic aneurysms (cAAs) (those requiring at least a suprarenal clamp site). We performed a meta-analysis to ascertain whether CRP improves kidney-related outcomes after open surgical cAA repair. METHODS: Patients of any age or gender who had undergone open surgical repair of cAAs were included. Primary outcomes were the presence of postoperative kidney injury, the need for dialysis and mortality related to kidney injury. We compared patients who were treated with any intraoperative CRP strategy to a control population without CRP. We used a fixed-effects model to analyze derived odds ratios (ORs) and assess heterogeneity. We performed risk of bias analysis to identify potential confounding elements. RESULTS: Among the 935 studies screened, 5 primary articles met the inclusion criteria. Cold renal perfusion significantly reduced postoperative acute kidney injury (OR 0.46 [95% confidence interval 0.32-0.68], Z = 3.98, p = 0.001). Only 1 study included data for the other primary outcomes. The data were considered homogeneous, with Cochrane Q = 0.23 and I 2 of 0%. CONCLUSION: This meta-analysis showed reduced postoperative acute kidney injury with the use of CRP during open cAA repair. A prospective randomized controlled trial to perform further subgroup analysis and research the various types of CRP solutions may be warranted to identify further possible benefits.

Diagnosing and treating Mycobacterium kansasii.

ABSTRACT: This article describes an 18-year-old immunocompetent patient who developed Mycobacterium kansasii, manifested with shortness of breath and a cavitary lung lesion seen on radiograph. Initial sputum smears were negative; however, after 2 weeks, the cultures grew M. kansasii and the patient was started on an antimycobacterial regimen.

Impact of an emergency endovascular aneurysm repair protocol on 30-day ruptured abdominal aortic aneurysm mortality.

OBJECTIVE: To characterize the longstanding impact of an emergency endovascular aneurysm repair (EVAR) protocol for ruptured abdominal aortic aneurysm (rAAA) on 30-day mortality. METHODS: All adult patients with an rAAA who underwent a surgical or endovascular intervention at a tertiary care center between March 2001 and December 2018 were evaluated. An emergency EVAR protocol was introduced in January 2004. The primary outcome was 30-day mortality, which was calculated using risk-adjusted logistic regression for the preprotocol and postprotocol periods. A risk-adjusted cumulative sum analysis examined changes in 30-day mortality after protocol implementation. RESULTS: We identified 376 patients with rAAA between 2001 and 2018 (75 preprotocol and 301 postprotocol), with a decreasing incidence of rAAA during the study period. The introduction of the protocol in 2004 was associated with increased EVAR use (63.6% vs 6.7%; P < .001). Patients managed according to the protocol were more frequently unstable (systolic blood pressure [SBP] of ≤80 mm Hg, 46.5% postprotocol vs 22.7% preprotocol; P < 0.001), with a lower average SBP (87.4 mm Hg postprotocol vs 106 mm Hg preprotocol; P < .001) and worse renal function (estimated glomerular filtration rate 61.5 mL/min postprotocol vs 83.2 mL/min preprotocol; P < .001). The risk-adjusted 30-day mortality was 23.2% with the emergency EVAR protocol, versus 35.8% preprotocol (P = .0727). A subgroup analysis demonstrated improved the 30-day mortality for unstable patients (SBP of ≤80 mm Hg) at 38.0% (vs 62.4% preprotocol introduction; P = .0190). A cumulative sum analysis demonstrated worse than expected mortality outcomes in the preprotocol period, and stability of surgical performance over 15 years after protocol introduction. CONCLUSIONS: On reflection of a 17-year experience with EVAR for rAAA, the implementation of an emergency EVAR protocol demonstrated stable surgical performance for all patients with an rAAA and evidence of improved 30-day mortality for unstable patients with an rAAA. Since the protocol introduction, EVAR has become a mainstay intervention and, despite an increase in comorbid patients, the overall incidence of rAAA is declining. EVAR should be considered the first-line intervention for the appropriate patient unstable with an rAAA.

Deep-learning method for fully automatic segmentation of the abdominal aortic aneurysm from computed tomography imaging.

Abdominal aortic aneurysm (AAA) is one of the leading causes of death worldwide. AAAs often remain asymptomatic until they are either close to rupturing or they cause pressure to the spine and/or other organs. Fast progression has been linked to future clinical outcomes. Therefore, a reliable and efficient system to quantify geometric properties and growth will enable better clinical prognoses for aneurysms. Different imaging systems can be used to locate and characterize an aneurysm; computed tomography (CT) is the modality of choice in many clinical centers to monitor later stages of the disease and plan surgical treatment. The lack of accurate and automated techniques to segment the outer wall and lumen of the aneurysm results in either simplified measurements that focus on few salient features or time-consuming segmentation affected by high inter- and intra-operator variability. To overcome these limitations, we propose a model for segmenting AAA tissues automatically by using a trained deep learning-based approach. The model is composed of three different steps starting with the extraction of the aorta and iliac arteries followed by the detection of the lumen and other AAA tissues. The results of the automated segmentation demonstrate very good agreement when compared to manual segmentation performed by an expert.

Zone 0 Aortic Arch Reconstruction Using the RelayBranch Thoracic Stent Graft.

Endovascular therapies have had a considerable impact on contemporary management of thoracic aortic disease. Still, with the anatomic challenges of the aortic arch, endovascular experience with devices that traverse the arch and deploy in the Zone 0 position remains limited. We report the first Canadian experience with the RelayBranch Thoracic Stent Graft (Terumo Aortic, Sunrise, FL) with Zone 0 deployment for total endovascular aortic arch repair in a patient at very high risk for redo open surgery. We demonstrate safe deployment of the device and successful treatment of a type 1A endoleak. Features of the RelayBranch design that mitigate challenges of arch deployment are also discussed.

Les traitements endovasculaires ont eu un impact considérable sur la gestion contemporaine des pathologies de l'aorte thoracique. Pourtant, en raison des contraintes anatomiques de la crosse aortique, l'expérience endovasculaire avec des dispositifs qui traversent la crosse et se déploient dans la zone 0 reste limitée. Nous rapportons la première expérience canadienne de l'endoprothèse thoracique RelayBranch avec déploiement (Terumo Aortic, Sunrise, FL) en zone 0 pour une réparation endovasculaire totale de la crosse aortique chez un patient présentant un risque très élevé de reprise de chirurgie ouverte. Nous décrivons le déploiement en toute sécurité du dispositif et le traitement réussi d'une endofuite de type 1A. Enfin, nous examinons les caractéristiques du système RelayBranch qui limitent les difficultés liées au déploiement du dispositif dans la crosse aortique.

Rapid endovascular bailout revascularization of the renal arteries with a steerable guiding sheath after endovascular abdominal aortic aneurysm repair.

Advancements in endovascular therapy have made it increasingly available for patients with complex cases but not without complications. Unintentional coverage of the renal arteries is a rare occurrence during endovascular aortic aneurysm repair. Given the potentially devastating repercussions, it is important that surgeons understand the suitability and the risks and benefits of the available revascularization options. We have described two cases of unintentional renal coverage, with subsequent successful bailout via direct manipulation of the stent-graft with a steerable sheath. We also conducted a review of the reported data, discussed the breadth of management options and their technical aspects, and provided several distinct solutions.

The Many Care Models to Treat Thoracic Aortic Disease in Canada: A Nationwide Survey of Cardiac Surgeons, Cardiologists, Interventional Radiologists, and Vascular Surgeons.

BACKGROUND: Several specialties treat thoracic aortic disease, resulting in multiple patient care pathways. This study aimed to characterize these varied care models to guide health policy. METHODS: A 57-question e-survey was sent to staff cardiac surgeons, cardiologists, interventional radiologists, and vascular surgeons at 7 Canadian medical societies. RESULTS: For 914 physicians, the response rate was 76% (86 of 113) for cardiac surgeons, 40% (58 of 146) for vascular surgeons, 24% (34 of 140) for radiologists, and 14% (70 of 515) for cardiologists. Several services admitted type B dissections (vascular 37%, cardiology 31%, cardiac 18%, other 7%), and care was heterogeneous. Ownership of disease management was overestimated relative to the perspective of the other specialties. Type A dissection admissions and treatment were more uniform, but emergent call coverage varied. A 24/7 aortic specialist on-call schedule was present only 4% of the time. "Aortic" case rounds promoted attendance by a broader aortic specialty contingency relative to rounds that were specialty specific. Although 89% of respondents felt an aortic team was best for patient care, only 54% worked at an institution with an aortic team present, and only 28% utilized an aortic clinic. Questions designed to define an aortic team derived 63 different combinations. CONCLUSIONS: Thoracic aortic disease follows a network of undefined and variable care pathways, despite its high-risk population in need of complex treatment considerations. Multidisciplinary aortic teams and clinics exist in low volume, and the "aortic team" remains an obscure construct. A multispecialty initiative to define the aortic team and outline standardized navigation pathways within the health systems hospitals is advocated.

CONTEXTE: La prise en charge de la maladie de l'aorte thoracique peut faire appel à plusieurs spécialités, ce qui a pour effet de multiplier les trajectoires de soins des patients. Cette étude visait à caractériser ces différents modèles de soins afin d'éclairer l'élaboration des politiques de santé. MÉTHODOLOGIE: Un sondage électronique de 57 questions a été envoyé aux chirurgiens cardiaques, aux cardiologues, aux radiologistes interventionnels et aux chirurgiens vasculaires membres de 7 associations médicales canadiennes. RÉSULTATS: Sur un total de 914 médecins, le taux de réponse a été de 76 % (86 sur 113) chez les chirurgiens cardiaques, de 40 % (58 sur 146) chez les chirurgiens vasculaires, de 24 % (34 sur 140) chez les radiologistes et de 14 % (70 sur 515) chez les cardiologues. Plusieurs services avaient admis des cas de dissection aortique de type B (chirurgie vasculaire 37 %, cardiologie 31 %, chirurgie cardiaque 18 %, autre 7 %) et les soins étaient hétérogènes. Les spécialistes surestimaient leur responsabilité de la prise en charge des cas par rapport à celle des autres spécialistes. Les admissions de cas de dissection de type A et leur traitement étaient plus uniformes, mais la présence de spécialistes de garde pouvant traiter les cas urgents était variable. La présence continue d'un spécialiste de l'aorte de garde n'était observée que pendant 4 % du temps. Les séances de discussion de cas « aortiques ¼ favorisaient la participation par une gamme plus large de spécialistes de l'aorte que les discussions axées sur une spécialité donnée. Si 89 % des répondants estimaient qu'une équipe « aortique ¼ était la meilleure option pour les soins aux patients, ils n'étaient que 54 % à travailler dans un établissement disposant d'une telle équipe et 28 % à utiliser les services d'une clinique de l'aorte. En réponse aux questions portant sur les éléments constitutifs d'une équipe aortique, 63 combinaisons différentes de spécialités ont été proposées. CONCLUSIONS: La prise en charge de la maladie de l'aorte thoracique emprunte un dédale de trajectoires de soins non définies et variables, alors que sa population à haut risque a besoin de traitements complexes. Les équipes multidisciplinaires et les cliniques spécialisées dans le traitement de l'aorte sont rares, et la notion d' « équipe aortique ¼ demeure un concept obscur. Nous préconisons une initiative réunissant des spécialistes de différents domaines pour définir les éléments constitutifs d'une équipe aortique et établir des trajectoires de navigation normalisées au sein des hôpitaux du système de santé.

Linking Aortic Mechanical Properties, Gene Expression and Microstructure: A New Perspective on Regional Weakening in Abdominal Aortic Aneurysms.

Background: Current clinical practice for the assessment of abdominal aortic aneurysms (AAA) is based on vessel diameter and does not account for the multifactorial, heterogeneous remodeling that results in the regional weakening of the aortic wall leading to aortic growth and rupture. The present study was conducted to determine correlations between a novel non-invasive surrogate measure of regional aortic weakening and the results from invasive analyses performed on corresponding ex vivo aortic samples. Tissue samples were evaluated to classify local wall weakening and the likelihood of further degeneration based on non-invasive indices. Methods: A combined, image-based fluid dynamic and in-vivo strain analysis approach was used to estimate the Regional Aortic Weakness (RAW) index and assess individual aortas of AAA patients prior to elective surgery. Nine patients were treated with complete aortic resection allowing the systematic collection of tissue samples that were used to determine regional aortic mechanics, microstructure and gene expression by means of mechanical testing, microscopy and transcriptomic analyses. Results: The RAW index was significantly higher for samples exhibiting lower mechanical strength (p = 0.035) and samples classified as low elastin content (p = 0.020). Samples with higher RAW index had the greatest number of genes differentially expressed compared to any constitutive metric. High RAW samples showed a decrease in gene expression for elastin and a down-regulation of pathways responsible for cell movement, reorganization of cytoskeleton, and angiogenesis. Conclusions: This work describes the first AAA index free of assumptions for material properties and accounting for patient-specific mechanical behavior in relation to aneurysm strength. Use of the RAW index captured biomechanical changes linked to the weakening of the aorta and revealed changes in microstructure and gene expression. This approach has the potential to provide an improved tool to aid clinical decision-making in the management of aortic pathology.

A novel combined fluid dynamic and strain analysis approach identified abdominal aortic aneurysm rupture.

Clinical decision-making for surgical repair of abdominal aortic aneurysms based on maximum aortic diameter presents limitations as rupture can occur below threshold for some aneurysms, whereas others are stable at large sizes. The proposed approach combines hemodynamics and geometric indices with in vivo deformation analysis to assess local weakening of the aortic wall for a case of impending rupture that was confirmed during open surgical repair. A new combined index, the Regional Rupture Potential, is introduced to help the assessment of individual aneurysms and their rupture risk, providing a rationale for clinical decisions.