Arch Branches Research Articles

Multiscale modelling of Potts shunt as a potential palliative treatment for suprasystemic idiopathic pulmonary artery hypertension: a paediatric case study

Potts shunt (PS) was suggested as palliation for patients with suprasystemic pulmonary arterial hypertension (PAH) and right ventricular (RV) failure. PS, however, can result in poorly understood mortality. Here, a patient-specific geometrical multiscale model of PAH physiology and PS is developed for a paediatric PAH patient with stent-based PS. In the model, 7.6mm-diameter PS produces near-equalisation of the aortic and PA pressures and Q_p/Q_s (oxygenated vs deoxygenated blood flow) ratio of 0.72 associated with a 16% decrease of left ventricular (LV) output and 18% increase of RV output. The flow from LV to aortic arch branches increases by 16%, while LV contribution to the lower body flow decreases by 29%. Total flow in the descending aorta (DAo) increases by 18% due to RV contribution through the PS with flow into the distal PA branches decreasing. PS induces 18% increase of RV work due to its larger stroke volume pumped against lower afterload. Nonetheless, larger RV work does not lead to increased RV end-diastolic volume. Three-dimensional flow assessment demonstrates the PS jet impinging with a high velocity and wall shear stress on the opposite DAo wall with the most of the shunt flow being diverted to the DAo. Increasing the PS diameter from 5mm up to 10mm results in a nearly linear increase in post-operative shunt flow and a nearly linear decrease in shunt pressure-drop. In conclusion, this model reasonably represents patient-specific haemodynamics pre- and post-creation of the PS, providing insights into physiology of this complex condition, and presents a predictive tool that could be useful for clinical decision-making regarding suitability for PS in PAH patients with drug-resistant suprasystemic PAH.

Computed Tomographic Analysis of Aortic Arch Branching Patterns: Revisited

Branching pattern of aortic arch (AA) has a direct impact on the outcomes of thoracic surgical and angiographic procedures. Since, geographical variations in the branching pattern of AA have been described, this descriptive cross-sectional study describes the AA variations in a Sri Lankan population compared to the available global data. For that, contrast-enhanced computed tomographic studies (CTC) of thorax (n = 219) performed in males (49.3%) and females (50.7%), aged 59 ± 17 years (range: 4 to 96 years), were evaluated. Branching patterns of AA were categorized into seven types as described by Popieluszko et al. Only, four AA types were identified in the study population: type 1 (90%; n = 197), type 2 (n = 10, 4.6%), type 3 (n = 8, 3.7%), and type 6 AA (n = 4; 1.8%). The prevalence of AA variations was 10%. Type 1 AA was the most prevalent pattern in both genders: female, 91%; males, 88.9%. The most prevalent AA variant in females was type 2 (n = 6; 5.4%); males type 3 (n = 5; 4.6%). However, the branching pattern of AA has not demonstrated a significant gender influence (odds: 0.792; 95% CI: 0.327–1.917; p = 0.605). Variations in branching pattern of AA are as high as 10% among Sri Lankans. Thus, an in-depth knowledge on population specific prevalence of AA variants would influence the modifications of surgical approaches and the choice of angiographic catheters to be utilized, which in turn would minimize inadvertent vascular injuries during thoracic surgical and angiographic interventions.

Surgical treatment of aneurysms of aortic arch branches and vessels of the upper extremities

Aneurysms of theaortic arch branches and vessels of the upper extremities are dangerous and there is a high probability of mortality due to rupture of the aneurysm or stroke. The indication is surgical treatment, regardless of the age and size of the aneurysms. The frequency of deaths and strokes that occurred during operations for carotid artery aneurysms is about 2%, which is associated with distal embolism of intracerebral vessels and the contents of the aneurysm cavity. One of the most common causes of aneurysms of the branches of the aortic arch and vessels of the upper extremities are atherosclerosis, nonspecific aortoarteritis and posttraumatic aneurysms. The study included 38 patients with aneurysms of the branches of the aortic arch and arteries of the upper extremities operated in the vascular surgery department over the past 10 years, whose total age ranged from 19 to 76 years. There were 84% men, 16% women. Aneurysms of the carotid arteries and its branches (temporal artery) were diagnosed in 58%, subclavian arteries in 16%, arteries of the upper extremities in 26%. The size of aneurysms of the branches of the aortic arch and arteries of the upper extremities ranged from 2.5 cm to 10 cm. The average size is 6.3±1.8 cm. When choosing the method of treatment of aneurysms of the branches of the aortic arch and arteries of the upper extremities, preference was given to performing reconstructive operations without the use of additional materials, which were performed in 52% cases), in 13 of these cases, excision of a false aneurysm with stitching of the defect was performed, in 6 of these cases, resections of aneurysms with end-to-end anastomosis were performed. In 48% cases, operations with the use of synthetic materials and autovenous plastic surgery were performed, and endovascular interventions were also performed in 4 cases. The most frequent type of surgery performed is resection of an aneurysm with a lateral suture – 34% cases. Resection of the anastomosis aneurysm at the end of the arteries – 16%, and prosthetics – in 8% cases (synthetic alloprosthetics in one and with autovenous prosthetics in two cases). After resection of subclavian artery aneurysm due to large diastasis of blood flow, reconstruction was performed by bypass surgery or prosthetics. Arterial aneurysm resection with autovenous patch was performed in 13% cases, and with allosunting – in 8% cases. Excision of an aneurysm of the axillary artery on the left with the restoration of a synthetic patch – in 5% cases. Ligation of an aneurysm in the temporal artery was performed in 2 cases (5%), this type of operation was performed with an aneurysm of non-main vessels, as well as in vessels with collateral blood flow in the distal area of the vessels. Implantation of a stentgraft into the right subclavian artery – in 3 cases (8%). X-ray endovascular embolization of aneurysm – in 3% case. Positive results in the postoperative period were observed in 92% patients. One (3%) patient developed complications in the form of hematomas after aneurysm resection. In 5% cases - lymphorrhea after excision of a false aneurysm

Branches of the aortic arch of the rat

Branches of the aortic arch of the rat

Morphometric Analysis of Brachiocephalic Trunk in Brazilian Cadavers of Human Foetuses

Introduction: The Brachiocephalic Trunk (BCT) is the largest branch of the aortic arch, with an average of 4-5 centimetres length. It usually divides into two vessels, the Right Common Carotid Artery (RCCA) and the Right Subclavian Artery (RSA). Aim: To conduct a morphometric study of BCT in cadavers of human foetuses and associate it with gender. Materials and Methods: An observational study was conducted from year 2012 to 2020, in which 35 foetal cadavers (18 male and 17 female) were dissected and fixed in 10% formalin, all belonging to the Human Anatomy Laboratory of the Morphology Department of the Federal University of Sergipe, Aracaju, SE, Brazil. After dissection and exposure of the aortic arch and its branches, measurements were made of the BCT length (from the edge of the aortic arch to its division into the right common carotid and subclavian arteries) and outside diameter (at the origin of the aortic arch) using a 0.05 mm precision digital calliper. The t-Student test was used for independent or unpaired samples to compare the BCT morphometric values in relation to gender, taking p<0.05 as statistically significant. Data were analysed using the Bioestat 5.3. Results: The length of the BCT varied from 6.19-15.34 mm, with an average of 10.22 mm, and its diameter from 1.51-5.11 mm, with an average of 3.16 mm. The comparative analysis between morphometric measurements and gender did not show any statistically significant difference (p>0.05). Conclusion: The knowledge of the BCT morphometry in foetuses can assist in the safe execution of various surgical procedures in the mediastinum, as it reduces the chances of serious complications resulting from these procedures.

Aberrant Right Subclavian Artery. A Series of Case Reports and Discussion of Morphology and its Clinical and Surgical Implications

Aberrant right subclavian artery (arteria lusoria) is a rare embryological abnormality but the most common among aortic arch vascular anomalies. It represents an anatomical variant of right subclavian artery originating as the last branch of aortic arch, passing then retroesophageal to the normal position. It is usually asymptomatic and is found mostly incidentally during imaging examinations. Symptoms are produced when the aberrant artery compresses the nearby structures and the most frequent symptoms are dysphagia and dyspnea. It may be associated with other vascular or heart abnormalities. We are presenting a series of case reports which presented an aberrant right subclavian artery alone or associated with other vascular abnormalities, diagnosed incidentally in adult patients while performing CT examinations for other reasons. Through a literature review we aim to discuss the clinical implications of this vascular anomaly, to point out the importance of being aware of it especially in patients with dysphagia or dyspnea or in patients who undergo operations in the thorax and neck or vascular surgery and endovascular procedures involving the aortic arch and its branches.

Magnetic Resonance Angiography and Multidetector CT Angiography in the Diagnosis of Takayasu's Arteritis: Assessment of Disease Extent and Correlation with Disease Activity.

Takayasu's Arteritis (TA) is a large vessel vasculitis with diverse clinical presentations and arterial vascular bed involvement.It is characterized by chronic, nonspecific inflammation of all layers of the vessel wall which results in stenosis, occlusion, dilatation, or aneurysm formation in the involved blood vessels. The study included 36 patients of TA. All patients fulfilled the modified Ishikawa's diagnostic criteria for TA. All patients were evaluated for clinical presentation, angiographic findings, and severity of the disease. The disease activity was assessed based on Erythrocyte Sedimentation Rate (ESR) and C-Reactive Protein (CRP) and also by CT Angiography (CTA)/Magnetic resonance angiography (MRA) imaging. The angiographic types were classified based on the International TA Conference in Tokyo 1994 angiographic classification. A total of 36 patients were included in the study, 86% were females and a mean age of 21.6 years. Hypertension (78%) was the most common clinical presentation. Type V was the most common angiographic type (42%) followed by type III (25%), type IV (14%), type IIb (11%), type I (5%) and type IIa (3%). Among the aortic arch branches the left subclavian artery (50%), right subclavian artery (38.8%), left vertebral artery (33.3%) and left common carotid artery (27.7%) were the most commonly involved arteries. Disease activity based on CT / MR imaging showed a significant statistical correlation with elevated ESR and positive CRP (p < 0.0001). Mediastinal lymphadenopathy was seen in 21 patients out of which 11 had active disease. However, no significant correlation was found between mediastinal lymphadenopathy and disease activity. TA presents with varied symptomatology and differing vascular involvement. CT/MR angiography is effective in diagnosis and accurately predicted the active stage of the disease.

Short-term results of off-pump and on-pump aortic arch debranching during type I hybrid arch repair: A single-center experience

BackgroundCompared with off-pump surgeries, cardiopulmonary bypass (CPB) is associated with a high systemic inflammatory response and with substantial myocardial injury, especially in high-risk subgroups. Every effort should be exerted to minimize the role of CPB without affecting the safety and outcome. Classically, aortic arch surgeries were done using CPB and deep circulatory arrest together with cerebral brain protection strategies. With the development of endovascular techniques, the role of CPB decreased. Management of aortic arch pathologies carries special needs, specifically rerouting of the great vessels and preparing a landing zone.ObjectivesTo assess the effectiveness and safety of off-pump aortic arch debranching during type I hybrid aortic arch repair.Patients and methodsWe report our single-center experience of rerouting aortic arch branches (debranching) without using CPB, consisting of bypass grafting of the aortic arch branches off pump, preparing a landing zone for endovascular aortic repair. The preoperative, operative, and postoperative data were collected and analyzed retrospectively. Starting from 2015, 20 low-risk patients were subjected to type I aortic arch hybrid repair, whereas the Dacron tube graft was anastomosed to a normal ascending aorta, preparing a landing zone to the subsequent stenting of arch and descending aorta. CPB was used in 10 patients, and off-pump technique was used in the remaining group. Preoperative, operative, and postoperative data were collected and analyzed to compare the results.ResultsAll surgeries went uneventful, with mean operative time of 141.5 ± 24.3 min for group I (on-pump group) and 137.5 ± 14.6 for group II (off-pump group). There were no conversions to CPB in off-pump group. There was no sternotomy for bleeding in off-pump group, compared with only one patient explored for postoperative bleeding in CPB group. All patients in both groups went without any neurological deficit of significance, with no mortality in the 30 days of follow-up.ConclusionOff-pump debranching of aortic arch followed by endovascular repair is a safe and reproducible technique, compared with the gold standard technique using CPB. However, further efforts using intraoperative cerebral perfusion monitoring techniques should be considered in the future.

CT Angiographic Study of Anatomical Variations of Aortic Arch Branches in Libyan Patients

The aim of this study is to determine the prevalence of the aortic arch branches variations in Libyan patients. The proportion of each type will be determined. Subjects and methods: This retrospective study was carried out on 229 cancer patients referred to the CT Scan Department for enhanced chest CT scanning. The scans showed that 83% of the patients had classical aortic arch branching patterns, and 17% had aortic arch variations. Bovine arch variation was the most common variation seen, reaching 11.4%, in which brachiocephalic and left common carotid arteries arise from the aortic arch in a common trunk. The prevalence of the left vertebral artery type that originates from the aortic arch was 3.9%. The prevalence of the aberrant right subclavian artery type was 2.6%, and of the aberrant right subclavian artery with common carotid trunk type was 1.74%. No relationship was found between gender and aortic arch branches variations. We conclude that aortic arch branching variations exist and hence, attention must be paid during chest surgical operations/radiological interventions to ensure safe procedure outcomes. Also, a CT scan is a good method to study such variations and the associated branching patterns.

Prenatal diagnosis of isolation of aortic brachiocephalic artery.

Isolated aortic brachiocephalic artery (IABA) is a rare congenital aortic arch anomaly. It is difficult to diagnose IABA prenatally and the prevalence in the prenatal population is unknown. To evaluate the echocardiographic characteristics and associations in fetuses with IABA. We retrospectively analyzed all cases of prenatal diagnosis of IABA from January 2012 to November 2020 and reviewed the follow-up results. Copy Number Variation Sequencing (CNV-Seq) was performed using the biological specimens of the of the fetuses and family members. Ten cases (10/45652, 0.022%) of IABA were identified in our center. The prevalence of the cases with isolated left subclavian artery (ILSCA) in the right aortic arch (RAA) population was 0.98% (6/613). The ILSCA was the most common isolated arch branch. All the isolated branches were on the opposite side of aortic arch in all the cases. The "ice stick" sign in the coronal section could be seen in most cases of IABA. Of the 10 cases, 8 (8/10, 80%) were associated with tetralogy of Fallot (TOF). Two cases of IABA were combined with 22q11.2 deletion syndrome. IABA is a rare aortic anomaly. ILSCA was the most common isolated arch branch and TOF was the most common associated intra-cardiac anomaly. The "ice stick" sign in the coronal section could indicate a diagnosis of the IABA.

Massive Sternal Osteophyte Compressing Aortic Arch Branch Graft.

We present a dramatic computed tomography scan demonstrating compression of a brachiocephalic graft by a massive sternal osteophyte, coming to light many years after aortic arch replacement surgery.

English

A bovine aortic arch is the most common variant of aortic arch branching in humans with a frequency ranging from 15 to 27% (1-2). It will be considered as a risk factor for aortopathy as anevrysm and dissection. Two cases were reported with association of bovine aortic arch and aortopathy. In both cases, the discovery of the anomaly of the aortic arch was fortuitous. A bovine aortic arch is frequent in patients with thoracic aortic disease than in the general population with a rapid evolution on the diameter of the aorta which expose patients to more complications such as anevrysm, rupture and dissection. It will be considered as a risk factor for aortopaty. Key words: Bovine aortic arch, aortopathy, common birth aortic arch.

Early diagnosis of giant cell arteritis - the basis of good outcome

Purpose: If untreated, giant cell arteritis can lead to blindness and stroke. The study objectives were to assess diagnostic procedures and treatment in early interventional clinic in University Clinical Centre Maribor in patients with temporal arteritis.&#x0D; Methods: Retrospective study (from 2012 to 2017) of patients diagnosed with temporal arteritis. We assessed epidemiological data, delay of diagnosis, and diagnostic procedures. Results were assessed with statistical methods (SPSS 22.0).&#x0D; Main goal: The main goal was to determinate the delay in days between symptom onset and admission to the interventional rheumatology clinic and to assess the causes of delay.&#x0D; Results: Fifty-three GCA (66 % female) patients with mean age 76.25 (from 63–89 years) years were included. Mean time duration of symptoms before admission to our early interventional clinic was 33.74 (0–180) days. The diagnostic procedure was completed in mean time of 2.04 days from the presentation at our interventional rheumatology clinic. The median time to the temporal artery biopsy (TAB) performed in 52 /53 patients was 2 days, with the median 2 days to the preliminary histological results from admission. TAB was positive in 43 (81.1%) of cases. The median time from admittance to colour Doppler sonography (CDS) of aortic arch branches was 2 days and it was positive in all 19 (35.8%) performed cases. 16 (30.2%) patients had polymyalgia rheumatica, 35 (66%) patients had visual disturbances, permanent one eye blindness occurred in 12 (22.64%) patients, and 2 (2.8%) patients experienced permanent blindness on both eyes. Seventeen patients (32.1%) were initially treated with intravenous methylprednisolone pulse. The mean initial dose of oral methylprednisolone was 45.55 (± 15.54) mg. All patients received low dose Aspirin.&#x0D; Conclusion: Early diagnosis and treatment of giant cell arteritis are very important as miss- or non-diagnosed GCA can lead to permanent blindness of the patient. With better education and public awareness, better access and better professional education of primary care physicians, and early admission to secondary interventional clinics we might spare these patients from the devastating consequences of the GCA.

Midterm Outcomes of an Adjustable Puncture Device for In Situ Fenestration During Thoracic Endovascular Aortic Repair

To evaluate the midterm outcomes of in situ fenestration (ISF) with an adjustable puncture device for aortic arch branch preservation during thoracic endovascular aortic repair (TEVAR). From October 2016 to April 2019, patients with complicated type B aortic dissection, thoracic aortic aneurysm > 5.5 cm in diameter, or aortic penetrating ulcer with a base > 20 mm or depth > 15 mm, who received TEVAR requiring a proximal sealing beyond zone 3 and underwent ISF using an adjustable puncture device, were included. After the procedure, patients were monitored at one, three, six, and 12 months, and annually thereafter. Peri-operative and follow up data were collected and analysed. Fifty of 51 patients (98%) received successful ISFs. One, two, or three aortic arch branches were preserved in 44, six, and one patient, respectively. Intra-operatively, eight type Ia endoleaks and one type II endoleak were found on angiography. One patient died of cerebral hernia three days post-procedure from a severe stroke; one patient suffered from transient paraplegia but recovered in two weeks; one patient had a non-disabling stroke. The median follow up was 31 months (22.5 - 36.5 months). At six month follow up, all nine unmanaged endoleaks had disappeared. One new type Ia endoleak was identified in a patient at the one month follow up which resolved spontaneously one year later. All revascularised arteries were patent at the last follow up. No fractures, migrations, or bridging stent kinks were found. In this largest mechanical based ISF study to date, an adjustable puncture device was shown to facilitate the procedure of ISF during endovascular repair of aortic diseases involving the aortic arch, with high success. The midterm outcome demonstrates the efficacy and safety of the device in assisting with preservation of aortic arch branches.

Branching patterns and anatomical variations of human aortic arch in Indian population

Knowledge of the aortic arch branching pattern is important during supra-aortic angiography, aortic instrumentation, thoracic and neck surgery. The aortic arch (AA) is located in the superior mediastinum. In 65–80% of the cases, the three branches arise from the aortic arch, namely, the brachiocephalic trunk (BCT), the left common carotid artery (LCCA), and the left subclavian artery (LSA). The purpose of this study is to describe different branching patterns of the arch of the aorta in Indian subjects. This observational study is based on dissection performed on Sixty embalmed arches of the aorta in adult Indian cadavers (in manuscript it was written as, 20 dissected heart specimens were collected of still-born fetuses) were exposed and their branches examined during cadaveric dissection in the department of Anatomy. The anatomical variations of the arch of the aorta and its branches, its branches at site of origin, and the distance of each branch from the point of origin to the median plane were measured. The usual three-branched pattern of arch of aorta was found in 44 specimens (73.33%). The common trunk for both brachiocephalic trunk and left common carotid artery was present in 11 specimens (18.33%). In 2 specimens (3.33%), the arch gives four branches. In 1 specimen (1.67%), give three branches. The wide spectrum of variations in the anatomical arrangement of the human aortic arch and its branches offer valuable information to catheterize the aortic arch and its branches for safely performing endovascular surgery. These anatomical and morphologic variations in the arch of the aorta and its branches are significant for diagnostic and surgical procedures in the thorax, head and neck regions.

P39.02 Does Neo-Adjuvant Chemotherapy Help in Locally Advanced Thymic Maliganancy?

Neoadjuvant chemotherapy is used to downsize thymic malignancies and improve R0 resection. However, there is no level I evidence for this. Here, we present our experience with neoadjuvant chemotherapy for locally advanced thymomas from a tertiary cancer center in India. This is a retrospective analysis of a prospective database. (Jan05 to Dec20) We included the following patients receiving neoadjuvant chemotherapy: Unresectable: Involving aortic arch / branches, main pulmonary trunk, heart Borderline Resectable: Involving SVC, brachiocephalic vein, main PA / branches, lung parenchyma Volumetric analysis was done using “ellipsoid” method for tumor volumes. Survival analysis was performed with Kaplan Meier method. Forty-one patients received neoadjuvant chemotherapy. At presentation, 16(41.5%) were unresectable, 25(56.1%) were borderline resectable. Most common structures at risk were arch aorta and branches(31.7%), SVC(24.39%) and main Pulmonary Artery(19.51%). Average tumor volume was 655.75cm3(90.45 – 4212.0) Good proportion of patients completed the planned chemotherapy(90.24%). However, only 56.1% came up for surgery. 4 progressed, 2 died due to chemotherapy related toxicity, 3 refused surgery and 9 remained unresectable. 12.5% of unresectable tumors and 44.0% of borderline tumors underwent R0 resection. 3/41 patients had complications Clavien-Dindo 3b and above with 1 mortality. The best volume reduction was seen in thymoma B2(54.84%) and thymic carcinomas(42.02%). At a median follow up of 34 months, 3 patients had local and 2 had systemic recurrences. Patients with R0 resection did significantly better than those with R+ resections or found unresectable.(p=0.03) R0 resectability remains the most important predictor of survival in thymic neoplasms. Neoadjuvant chemotherapy introduces the possibility of R0 reaction in unresectable tumors and should be strongly considered. In borderline resectable tumors, neoadjuvant chemotherapy affords a higher rate of R0 resection with less complex resections and minimal morbidity. This finding should be further evaluated in prospective multi centric studies

Cervical Aortic Arch with Hypoplastic Left Common Carotid Artery and Subaortic Left Brachiocephalic Vein.

Cervical Aortic Arch with Hypoplastic Left Common Carotid Artery and Subaortic Left Brachiocephalic Vein.

342 SURGICAL TREATMENT OF ESOPHAGEAL CANCER WITH VARIATIONS OF THE AORTIC ARCH AND ITS BRANCHES

Abstract The variations of the aortic arch and its branches are rare. The surgical treatment of esophageal cancer would be challenged for combination with this anomaly. This study intends to review significant group cases to analyze the influence of this variation on esophagectomy. Methods From 2013 to 2019, 19 patients with aortic arch and brachiocephalic vessels variations underwent esophagectomy, accounting for 0.3% during the same period. The abnormalities were distributed as follows: left-sided aortic arch combined with aberrant right subclavian artery (LAA + ARSA) occurred 13 cases, right-sided aortic arch anomalies with mirror image arch branches (RAA + MIAB) in 1 case, and right-sided aortic arch combined with aberrant left subclavian artery (RAA + ALSA) in 5 case. Of the patients with LAA + ARSA, 11 patients underwent the McKeown esophagectomy, and 2 patients via transhiatal. All patients with RAA underwent left thoracotomy approach.Perioperative outcomes and long-term survival were analyzed. Results The tumors were mostly located in the upper and middle thorax (47.4% and 42.1%). The R0 resection rate was 89.5% (17/19). Recurrent laryngeal nerve injury occurred in 2 patients, anastomotic fistula in 1 patient. Two patients died within 30 days postoperatively. The yield of lymph nodes was 21.8 ± 9.4. The sampling rate of lymph nodes along the recurrent laryngeal nerve was 61.5% in LAA + ARSA group, while 16.7% in RAA group. Recurrence happened in 5 cases (29.4%), including 2 regional relapse. Four patients died after recurrence, with a median time to death of 20 months (range: 10–48 months). Conclusion For aortic arch and brachiocephalic artery variations in esophageal cancer, aberrant right subclavian artery and right-sided aortic arch are the most common types. The surgical strategy is closely related to the aortic arch position. Due to the combined variation of the recurrent laryngeal nerve, the upper mediastinal lymph nodes dissection would be conservative, but with acceptable oncologic results.

Effect of Subject-Specific, Spatially Reduced, and Idealized Boundary Conditions on the Predicted Hemodynamic Environment in the Murine Aorta.

Mouse models of atherosclerosis have become effective resources to study atherogenesis, including the relationship between hemodynamics and lesion development. Computational methods aid the prediction of the in vivo hemodynamic environment in the mouse vasculature, but careful selection of inflow and outflow boundary conditions (BCs) is warranted to promote model accuracy. Herein, we investigated the impact of animal-specific versus reduced/idealized flow boundary conditions on predicted blood flow patterns in the mouse thoracic aorta. Blood velocities were measured in the aortic root, arch branch vessel, and descending aorta in ApoE-/- miceusing phase-contrast MRI. Computational geometries were derived from micro-CT imaging and combinations of high-fidelity or reduced/idealized MR-derived BCs were applied to predict the bulk flow field and hemodynamic metrics (e.g., wall shear stress, WSS; cross-flow index, CFI). Results demonstrate that pressure-free outlet BCs significantly overestimate outlet flow rates as compared to measured values. When compared to models that incorporate 3-component inlet velocity data [[Formula: see text]] and time-varying outlet mass flow splits [[Formula: see text]] (i.e., high-fidelity model), neglecting in-plane inlet velocity components (i.e., [Formula: see text])) leads to errors inWSS and CFI values ranging from 10 to 30% across the model domain whereas the application of a steady outlet mass flow splits results in negligible differences in these hemodynamics metrics. This investigation highlights that 3-component inlet velocity data and at least steady mass flow splits are required for accurate predictions of flow patterns in the mouse thoracic aorta.

Aortic arch anomalies, embryology and their relevance in neuro-interventional surgery and stroke: A review.

Congenital aortic arch anomalies are commonly encountered during neurointerventional procedures. While some anomalies are identified at an early age, many are incidentally discovered later in adulthood during endovascular evaluations or interventions. Proper understanding of the normal arch anatomy and its variants is pivotal to safely navigate normal aortic arch branches and to negotiate the catheter through anomalies during neurointerventional procedures. This is particularly relevant in the increasingly "transradial first" culture of neurointerventional surgery. Moreover, some of these anomalies have a peculiar predilection for complications including aneurysm formation, dissection, and rupture during the procedure. Therefore, an understanding of these anomalies, their underlying embryological basis and associations, and pattern of circulation will help endovascular neurosurgeons and interventional radiologists navigate with confidence and consider relevant pathologic associations that may inform risk of cerebrovascular disease. Here, we present a brief review of the basic embryology of the common anomalies of the aortic arch along with their neurological significances and discuss, through illustrative cases, the association of aortic arch anomalies with cerebral vascular pathology. Understanding the aortic arch anomalies and its embryological basis is essential to safely navigate the cerebral vascular system during neurointerventional surgeries.