Variations Of Aortic Arch Research Articles

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.

Aortic Arch Variants and Anomalies: Embryology, Imaging Findings, and Clinical Considerations.

There is a wide spectrum of congenital anomalies or variations of the aortic arch, ranging from non-symptomatic variations that are mostly detected incidentally to clinically symptomatic variations that cause severe respiratory distress or esophageal compression. Some of these may be accompanied by other congenital heart diseases or chromosomal anomalies. The widespread use of multidetector computed tomography (CT) in clinical practice has resulted in incidental detection of several variations of the aortic arch in adults. Thus, radiologists and clinicians should be aware of the classification of aortic arch anomalies and carefully look for imaging features associated with a high risk of clinical symptoms. Understanding the embryological development of the aortic arch aids in the classification of various subtypes of aortic arch anomalies and variants. For accurate diagnosis and precise evaluation of aortic arch anomalies, cross-sectional imaging modalities, such as multidetector CT or magnetic resonance imaging, play an important role by providing three-dimensional reconstructed images. In this review, we describe the embryological development of the thoracic aorta and discuss variations and anomalies of the aortic arch along with their clinical implications.

Propensity of Stroke in Standard versus Various Aortic Arch Variants: A 200 Patients Study.

Background:Abnormal origin of arteries from the aortic arch could alter the hemodynamics. Therefore, aortic arch variations might predispose patients to atherosclerosis, which would increase the stroke risk by impending thrombus formation.Objectives:To investigate the prevalence of various types of the anatomy of the aortic arch in ischemic stroke patients and determine if aortic morphology has any effect on early-onset strokes.Materials and Methods:Observational study including 200 imaging-confirmed (Non Contrast Computed Tomography(NCCT)/magnetic resonance imaging [MRI] of the brain) acute ischemic stroke patients. This was followed by computed tomography [CT]/MRI angiography of the arch of the aorta, neck vessels, and intracranial arteries. The occurrence of various types of standard and other aortic arch variants was studied. The prevalence of stroke and its characteristics were analyzed for demographics, types, location, and the predominant side of involvement among standard arch variants and standard versus various aortic arch variants. A P value < 0.05 was considered significant.Results:Standard arch Type I was the most common (P < 0.0001). Age at stroke onset in Type 1 was 61.83 years ± 2.78 years, in Type 2 was 59.8 years ± 3.55 years, and in Type 3 was 60.96 years ± 3.56 years (P = 0.0012). Among the bovine aortic arch, age at stroke presentation in Type A was 53.33 years ± 8.35 years, in Type B was 53.36 years ± 7.4 years, and in Type C was 63.25 years ± 9.25 years (P < 0.0001).Conclusions:Standard aortic arch Type 2, bovine aortic arch Type A, and Type B are associated with an early age at stroke presentation. During routine carotid evaluation by CT or MR angiography in stroke patients, it would be better to evaluate the aortic arch as well, especially in young patients.

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 Ultrasound Diagnosis of Double Aortic Arch versus Right Aortic Arch Variant in Vascular Ring Formation – Case Report and Review of the Literature

Prenatal Ultrasound Diagnosis of Double Aortic Arch versus Right Aortic Arch Variant in Vascular Ring Formation – Case Report and Review of the Literature

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.

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.

Investigating the Association between Aortic Arch Variants and Intracranial Aneurysms.

There is an association between anterior cerebral artery vessel asymmetry and anterior communicating artery aneurysm, presumably based on flow dynamics. The purpose of this study is to investigate the potential relationship between aortic arch branching patterns and incidence of intracranial aneurysm. This study included patients scanned over 1 year at our tertiary care center who underwent high-resolution imaging (computed tomography angiography or digital subtracted angiogram) of the head and neck arteries, aortic arch, and superior mediastinum. Exclusion criteria included patients with suboptimal images. Patient age, gender, aortic arch branching pattern, and the presence, location, and number of aneurysms were documented. Among the 1082 patients analyzed, 250 (23%) patients had a variant aortic arch branching pattern, 22 (8.8%) of whom had aneurysms. There were 104 patients with 126 aneurysms, with majority of patients with normal aortic arch branching pattern (n = 82, 79%). The most common variant was a common origin of the left common carotid artery and brachiocephalic trunk with or without direct origin of the left vertebral artery. Twenty-two patients with aneurysms had an aberrant aortic arch (21%), compared to 232 patients without an aneurysm (24%). Fischer exact test showed no statistically significant difference between the incidence of aneurysm with different aortic arch variant groups (two-tailed p-value = 0.715). To our knowledge, this is the first study to examine the association between aortic arch branching patterns and incidence of intracranial aneurysm. No significant association was found between aortic arch branching pattern and the incidence of intracranial aneurysm.

Anatomical organization of aortic arch variation with embryological basis and clinical application

Introduction: The variation in the aortic arch is well known and it has been demonstrated by number of researchers. Changes involved in the development of aortic arch system such as regression, retention or reappearance result in the variation in branching pattern of aortic arch. Variations of the branches of aortic arch are due to alteration of branchial arch arteries during embryonic period. The most common classical branching pattern of the aortic arch in humans comprises of three great vessels, which includes Brachiocephalic trunk, Left Common Carotid artery and Left Subclavian artery. Aim: The study is to determine the embryological basis correlating with clinical application and surgical procedures. Materials and Methods: A study was conducted in 50 formalin fixed cadaveric hearts, during a period of two years. In the routine dissection for 1st MBBS and also museum specimens we encountered 3variations in the branches of arch of aorta. Results: The variations in aortic arch branching pattern were observed in 4 cadaveric hearts (8%). Conclusion: The wide spectrum of variation in the human aortic arch and its branches offer valuable information to catheterize in endovascular surgery for diagnostic and surgical procedures in the thorax, head and neck regions. KEY WORDS: Aortic Arch (AA), Left Common Carotid (LCCA), Left Subclavian (LSA), Brachiocephalic Trunk (BCT), left vertebral artery(LVA).

A systematic classification of the left-sided aortic arch variants based on cadaveric studies' prevalence.

Typical branching pattern of the left-sided aortic arch consists of the brachiocephalic trunk (BCT), the left common carotid artery (LCCA) and the left subclavian artery (LSA). Variant patterns have been associated with a broad spectrum of pathologies. The meticulous knowledge of potential aortic arch variants is of utmost importance to radiologists, interventional cardiologists, vascular and thoracic surgeons. The current systematic review collects all aortic arch branching patterns and their frequency as published by various cadaveric studies, calculates prevalence taking into account the gender and the different people background, as well. All extracted variant patterns are classified into types and subtypes according to the number of emerging (major and minor) branches (1, 2, 3, 4 and 5) and to the prevalence they appear. In cases of similar prevalence, total cases were taken into consideration; otherwise the variants were classified under the title "other rare variants". A systematic online search of PubMed and Google books databases was performed only in cadaveric studies. Twenty studies with typical (78% prevalence) and variable (22%) branching patterns were included. Types 3b, 2b, 4b, 1b and 5b had aprevalence of81%, of13%, of5%, 0% and of0%, respectively. Common variants were the brachiocephalico-carotid trunk (BCCT, 49% prevalence), the aberrant left vertebral artery (LVA, 41%) and the aberrant right subclavian artery (ARSA, 8%). LVA of aortic origin was detected in 32%, the bicarotid trunk (biCT) in 5% and the bi-BCT trunk in 3%. Thyroidea ima artery, a minor branch emerging from the aortic arch was found in 2%. Coexisted variants were detected in 4% (ARSA with a distinct RCCA and LCCA origin), in 3% (BCCT with a LVA of aortic origin), in 2% (ARSA with a biCT and a vertebrosubclavian trunk). No significant gender or ethnic differences exist among the 5 branching types. The proposed classification scheme aims to become a valuable and easy to use tool in the hands of all physicians involved in diagnosis and treatment of aortic arch pathology. It could be also useful in anatomical education,as well.

Clinical Impact of Rare Aortic Arch Variant

This case report describes the clinical implications of peripheral arterial disease in a patient with a rare variant of the aortic arch branches. The patient was a 68-year old-female with an extensive cardiovascular history including multiple severe peripheral arterial stenoses, systemic and pulmonary hypertension, hyperlipidemia, coronary artery disease, multiple myocardial infarctions, atrial fibrillation, and possible aortic valve disease. The focus of the case report will be how the patient’s anatomical variant played a large role in maintaining cerebral circulation in the presence of significant stenoses of the right vertebral artery, left subclavian artery, and left common carotid artery.

Anatomical Considerations for Endovascular Intervention for Extracranial Carotid Disease: A Review of the Literature and Recommended Guidelines.

Patient selection for endovascular intervention in extracranial carotid disease is centered on vascular anatomy. We review anatomical considerations for non-traumatic disease and offer guidelines in patient selection and management. We conducted a systematic literature review without meta-analysis for studies involving anatomical considerations in extracranial carotid intervention for non-traumatic disease. Anatomical considerations discussed included aortic arch variants, degree of vessel stenosis, angulation, tortuosity, and anomalous origins, and atheromatous plaque morphology, composition, and location. Available literature suggests that anatomical risks of morbidity are largely secondary to increased procedural times and difficulties in intervention system delivery. We recommend the prioritization of endovascular techniques on an individual basis in cases where accessible systems and surgeon familiarity provide an acceptable likelihood of rapid access and device deployment.

The aortic arch in tetralogy of Fallot: types of branching and clinical implications.

Tetralogy of Fallot is the most common form of cyanotic CHD, with an incidence of 421 cases per million live births, constituting around 10% of CHD. Variations in aortic arch anatomy associated with tetralogy of Fallot, other than the incidence of right aortic arch (13-34%), are not frequently reported. A comprehensive analysis of a large number of tetralogy of Fallot cases is required to arrive at a compendious description of aortic arch anatomy. All patients with a diagnosis of tetralogy of Fallot who had CT or MRI either pre or post procedures between 1 January 2010 and 31 December 2019 at our hospital were included in the study. Using radiology consultants' reports and analysis of individual images, we identified the various morphological patterns of aortic arches prevalent in these patients. Out of 2684 patients who met the inclusion criteria, 1983 patients had left aortic arch (73.9%), 688 patients had right aortic arch (25.7%), four patients had cervical aortic arch (0.15%), eight patients had double aortic arch (0.3%), one patient had an aorto-pulmonary window (0.04%), and none of the patients had interrupted aortic arch. Sub-classification and clinical implications of the arch variations are described. Up to 10% of tetralogy of Fallot patients may have significant anatomical variations of aortic arch that would necessitate changes or additional steps in their surgical or interventional procedures.

Computational Fluid Dynamics Modeling of Proximal Landing Zones for Thoracic Endovascular Aortic Repair in the Bovine Arch Variant

To assess the endograft displacement forces (DF), which quantify the forces exerted by the pulsatile blood flow on the vessel wall and transmitted on the terminal fixation site of the endograft after its deployment in proximal landing zones (PLZs) of the bovine aortic arch variant. Thirty healthy aortic computed tomographic angiographies of subjects with bovine arch configuration (10 per type of arch, I-III) were selected for the purpose of the study. A 3-dimensional model of the aortic arch lumen was reconstructed. Computational fluid dynamics modeling was then used to compute DF magnitude and orientation (i.e., x, y, and z axes) in PLZs of each case. DF values were normalized to the corresponding aortic wall area to estimate equivalent surface traction (EST). DF were highest in zone 0, consistently with the greater surface area. DF in zone 3 were much greater than in zone 2 because of a 3-fold greater upward component (z axis) (P<0.001), being therefore mainly oriented orthogonally to the aortic blood flow and to the vessel longitudinal axis in that zone. EST progressively increased from zone 0 toward more distal PLZs, with EST in zone 3 being much greater than that in zone 2 (P<0.001). The same pattern was observed after stratification by type of arch. The bovine arch is associated with a consistent fluid dynamic pattern, which identifies in zone 3 an unfavorable biomechanical environment for endograft deployment.

A cadaveric study of the aortic arch branching patterns

This study was conducted to investigate the variations in the aortic arch branching patterns in the cadavers donated to the University of Texas Health at San Antonio, San Antonio, Texas. Branching patterns of vessels from the aortic arch in 56 cadavers (31 males and 25 females) were recorded after dissection of the mediastinum by the medical students. A previous meta‐analysis of variations in the adult aortic arch branching has grouped the aortic arch variants into seven different types. Our survey of cadaveric specimens revealed three of these types. The normal variant (Type 1) where the aortic arch gives rise to the brachiocephalic trunk (BT), the left common carotid (LCC) and the left subclavian (LS) arteries occurred in 69.6% (21 male and 18 female, 95% confidence interval: 56.6% to 80.2%) of cadavers. The bovine arch (BA) variant (type 2) of the aortic arch is a known congenital anomaly with both clinical and surgical significance. It is described as the common origin of the left common carotid artery (LCC) and the brachiocephalic trunk (BT) from the aortic arch. BA was present in 25% of cadavers (95% confidence interval: 15.4% to 37.8%), distributed evenly among male and female cadavers (7 male and 7 female). Type 3 variant, where the left vertebral artery (LV) was branching directly from the arch between the LCC and the left subclavian artery (LS) was noted in 5.3% (95% confidence interval: 1.3% to 15.2%) of the cadavers. Interestingly, all the cadavers found to have the type 3 variant were male. Knowledge of variations in the branching patterns of vessels from the aortic arch is essential to surgical planning to ensure optimal patient outcomes.

Verification of aortic arch variations through modern imaging

IntroductionThe aortic arch with its vessels offers one of the biggest varieties of branching patterns, which is barely beeing mentioned in modern medical textbooks though. The last big survey on the most common varieties had been published by Lippert in 1967 and, since then, not been verified, just republished. With these varieties being of great importance in certain fields of medicine, the up‐to‐dateness of Lippert’s data has been analysed.AimThe main objective is the analysis of CT‐Angiographies for branching varieties of the aortic arch and comparison of frequency distributions with Lippert 1967. The secondary objective is measuring the vessel lumen of varieties and comparison with matches of the standard variant to find out if varieties have influence on the vessel’s lumen.Material/MethodsThis retrospective cross‐sectional study includes 400 patients, more specificaly their CTAs from 01.01.2017 to 31.12.2017, obtained from the University Department of Biomedical Imaging and Image‐guided therapy, General Hospital Vienna. Incusion and exclusion criteria have been differently set up for main and secondary objective. Patients for the main objective have been excluded if they have had any kind of surgery altering their varieties, like bypass‐surgery. Patients for the secondary objective have have been excluded if they were under the age of 18 or have had any kind of diseases/surgery altering the supraaortic vessel’s lumen.The main objective has been represented with tabular comparisons. For the secondary objective patients not fulfilling the criteria have been excluded at first. Afterwards the different groups of varieties have been matched with groups of the standard variant similiar in age and distribution of sex. The vessel’s lumen then has been analysed and t‐tested.ResultsThe analysis and comparison of data in terms of frequency have been proved statistically in‐significant. Testing of V2_TBv with V1_TB (p&lt;0,001; α=0,05) as well as V2_ACCS with V1_ACCS (p&lt;0,001; α=0,05) have shown statistical significance.ConclusionDespite minor deviation after analysis with modern imaging the data of Lippert from 1967 can still be seen as up‐to‐date. In vascular surgery it may be neccessary to be considerate about the vessel lumen in case of any known variety of the branches of the aortic arch. Certain questions may ask for more detailed analysis.

Aortic Arch Anomalies and Pulmonary Artery Anomalies : Echocardiographic Evaluation

Congenital variants and anomalies of the aortic arch are important to recognize as they may be associated with vascular rings, congenital heart disease, and chromosomal abnormalities, and can have important implications for prognosis and management. The purpose of this article is to describe the embryology and anatomy of the aortic arch system, discuss aortic arch variants and review other malformations of the aortic arch, including interrupted aortic arch (IAA), hypoplastic aortic arch, and coarctation of aorta. I have also described few anomalies of pulmonary artery (PA) origin and bifurcation like PA sling which has clinical presentation similar to vascular ring and anomalous origin of PA from aorta which present as large aorto-pulmonary communication with congestive heart failure. Aortic arch variants and anomalies will be reviewed in the context of a theoretical double aortic arch system. Arch anomalies can be associated with symptoms, such as dysphagia lusoria in the setting of left aortic arch with aberrant right subclavian artery. Arch variants that form a vascular ring, such as double aortic arch, can result in respiratory distress due to tracheal compression.

Bovine Aortic Arch Variation in a Symptomatic Patient

Bovine Aortic Arch Variation in a Symptomatic Patient

Prevalence of Bovine Aortic Arch Variant and its Implication in Outcome of Patients with Acute Type B Aortic Dissection

Introduction - Bovine aortic arch represents the most common variation of the aortic arch with a prevalence of 1-41% according to cadaveral or imaging studies.1,2,3 Although in older studies this pattern has been considered to cause no physiological abnormalities and to have less clinical impact, nowadays with the evolution of the surgical and endovascular interventions in the aortic arch, the presence of this variant could pose significant challenges to the surgeon or even implicate the outcome.4,5 This study aims to investigate the prevalence of bovine aortic arch (BAA) among patients with acute and/or subacute aortic dissection (AD) and to provide an insightful view of the implication of this arch variant on the outcome. Methods - A retrospective cohort analysis of two prospectively maintained databases with all patients with acute/subacute type B AD admitted to two tertiary university hospitals between January 2006 and December 2016 was conducted. All diagnostic CTAs were retrospectively reevaluated by two independent observers. A control group of 110 oncological patients was used, where the CT-scan for staging demonstrated aortic arch anatomy with no evidence of thoracic aortic disease. Patients with congenital heart defects or connective tissue disorders were excluded from the study. The presence of BAA was determined if the innominate artery and left common carotid artery had their separation point cranial to the plane of the greater curvature of the aortic arch. Two patterns were referred to as a BAA: a common origin of the innominate artery and left common carotid artery (BAA1) and the origin of the left common carotid of the innominate artery (BAA2). Results - A total of 154 patients (mean age 58.75±12.89, 64.3% males) with acute/subacute type B AD during the study period were identified. A total of 264 CTAs, including the control group, were analyzed. Prevalence of 18.2% (n=48) for BAA variants was revealed in the cohort. An isolated left vertebral artery was found in 13 patients (4.9%) whereas an aberrant right subclavian artery in 5 patients (1.9%). The BAA prevalence among the patients with acute/subacute type B AD was not statistically significantly different from the control group (18.8% vs. 17.3%, p=0.435). With regard to the patients with acute/subacute type B AD, 12 patients (7.8%) succumbed within 30 days from diagnosis, whereas 13 patients were lost during the median follow up of 27.8 (range 1.3-172.5) months. Among the remaining, 18 further patients died, resulting in an overall mortality of 21.3%. The multivariate analysis revealed the presence of a BAA as an independent predictor for overall mortality (Adjusted OR 3.44, 95%CI 1.2–9.8). Conclusion - A difference in the prevalence of the BAA between patients with AD and control group could not be confirmed. In patients with acute/subacute type B AD, the presence of a BAA may be considered as a predictor for mortality. Larger studies are needed to further investigate this observation.

A Systematic Review and Meta-analysis of the Bovine Aortic Arch Variant as a Determinant of Thoracic Aortic Disease

Introduction: The Bovine Aortic Arch (BAA) is the second most common arch configuration in the general population.1Recent studies reported a higher BAA prevalence among patients affected with thoracic aortic disease (TAD).2-5This hypothesis, however, remains to be confirmed due to the limited evidence available. The objective of the present work was to statistically address the association between the BAA and the onset of TAD. Methods: A systematic review and meta-analysis was conducted according to the PRISMA statement standards.The PubMed, EMBASE and Cochrane databases were searched to identify all case series reporting about BAA and TAD between January 2008 and September 2018. A total of 462 studies were screened. The prevalence of BAA was assessed, and data analysis was performed considering the difference in the risk of TAD for the presence versus the absence of BAA. Results: Eight studies enrolling 10,513 subjects were retrieved for quantitative analysis. The prevalence of BAA among patients with TAD was higher (30.2%; 559/1852) than the prevalence in subjects without TAD (24.8%; 2367/9529). The risk of developing TAD was 1.4 times higher in subjects with BAA (Odds Ratio, 1.40; 95% CI 1,068-1,839).The test for an overall effect strongly indicated a significant association between BAA and TAD with a P value of < .0015 (Figure 1). The I2 was 78.1% with p< 0.001 for heterogeneity and therefore the random effect model was adopted. The Egger test did not show evidence of publication bias (p=0.317). Conclusion: Our meta-analysis strongly supports the hypothesis of a causative association between the presence of BAA and the onset of TAD. Our results warrant a specific and long-term surveillance for patients with BAA, and also a thorough awareness of the BAA potential clinical implications during image interpretation. Further studies are required to disclose the underlying pathophysiologic mechanism, which predispose these subjects to a higher risk of aortic disease. [Graph] Disclosure: Nothing to disclose