Incidence of Aortic Arch Anomalies in Patients with Thoracic Aortic Dissections

Surgical management of anomalous aortic right coronary artery discovered during acute type A aortic dissection: a case report

Anomalous aortic origin of the right coronary artery (RCA) is a rare anatomic anomaly that is present in ~1% of the general population, and is often discovered incidentally through imaging performed for another purpose. Despite being an uncommon phenomenon, aberrant right coronary arterial origins can have devastating manifestations in half of affected patients. These include myocardial infarction, arrhythmias, heart failure, syncope, and sudden cardiac death secondary to ischemia of the cardiac tissue. This report describes a case of a 48-year-old female patient that was initially found to have ST-elevation myocardial infarction. During cardiac catheterization, the patient was discovered to have a type A aortic dissection. Cardiothoracic surgery was consulted, and she was immediately transferred to the operating room for repair. During the procedure, an anomalous RCA was discovered with its origin in the dissected tissue, which was initially ligated and then bypassed using greater saphenous vein graft.

2022 ACC/AHA guideline for the diagnosis and management of aortic disease: A report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

A Comparative Study of Clinical and Aortic Morphological Characteristics between Bovine Aortic Arch and Normal Aortic Arch in Patients with Acute Type B Aortic Dissection

INTRODUCTION

The purpose of this study was to analyze the difference in clinical and aortic morphological features between the bovine aortic arch and normal aortic arch in patients with acute type B aortic dissection (aTBAD).

METHODS

A total of 133 patients diagnosed with aTBAD were retrospectively collected. Based on aortic arch morphology, they were divided into the bovine aortic arch group (n = 20) and the normal aortic arch group (n = 113). Aortic morphological features were assessed on computed tomographic angiography. Clinical and aortic morphological features were then compared between the bovine aortic arch and normal aortic arch groups.

RESULTS

Patients in the bovine aortic arch group were significantly younger and with higher weight and BMI than the normal aortic arch group (p < 0.001, p = 0.045, and p = 0.016, respectively). The total aortic length in the bovine aortic arch group was significantly shorter than that in the normal aortic arch group (p = 0.039). The tortuosity of descending thoracic aorta, the tortuosity of descending aorta, and the angulation of aortic arch were significantly lower in the bovine aortic arch group (p = 0.004, p = 0.015, and p = 0.023, respectively). The width of descending aorta, the height of aorta arch, and the angle of ascending aorta were significantly smaller in the bovine aortic arch group (p = 0.045, p = 0.044, and p = 0.042, respectively).

CONCLUSION

When the aTBAD occurred, patients with bovine aortic arch were prone to be younger and with higher BMI than those with normal aortic arch. The aortic curvature and the total aortic length were lower in patients with bovine aortic arch.

Anatomical Variations in Aortic Arch Branching Pattern: A Computed Tomography Angiography Study

INTRODUCTION

Variations in the branching pattern of the aortic arch (AA) are common. Modification of intravascular stents should be considered taking into account these AA branching variations. Identification of supra-aortic branching types and frequencies is important for specialists planning surgery in this region. In endovascular interventions to the AA, aortic stent grafts should be modified according to the variations of the branching patterns of the AA. In any surgical intervention to the region where the supra-aortic branches are located, ignorance of the variations may cause unwanted injuries or complications.

METHODS

In this study, 699 computed tomography angiography (CTA) images were reviewed to investigate AA branching variations using the Horos software (an open-source image viewer). Four groups were constructed based on the number of branches emerging from the aortic arch, which were further divided into subtypes.

RESULTS

A total of 699 CTA images from 320 males and 379 females were included in this study. The usual AA branching pattern (type 3b1) was found in 68.5% of the patients. The combined prevalence of other eight branching patterns, designated as variations, was 31.5%. Variation types 1b1, 3b2, and 4b5 were identified in one patient each. Overall, types 2b1 and 2b2 had a prevalence of 28.3%. The type 2b3 variation was observed in 1.6% of the patients. The least common variations were type 4b1 (0.7%) and type 3b2 (0.1%).

CONCLUSION

The identification of variations in AA branching patterns by CTA prior to surgical or endovascular interventions involving the aortic arch is important. Thus, specialists planning interventions in this region need to be aware and have knowledge of atypical aortic branching patterns. Higher prevalence rates of AA branching patterns compared to previous studies were identified in the Turkish population in this study and therefore, a comprehensive, multicenter study is needed to determine the cause of this differential finding.

2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate. Structure: Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

Case Report: Anomalous Origin of the Right Coronary Artery From the Left Sinus of Valsalva With Aortic Dissection: New Myocardial Ischemia Mechanism

The aortic anomaly of the right coronary artery (AAORCA) originating from the left aortic sinus (LCS) is a rare malformation that may result in sudden cardiac death (SCD), which may be due to the dilated aorta-pulmonary artery affecting the blood supply of the coronary artery. However, there are still some disputes about the treatment of the AAORCA. Herein, we present a rare case of AAORCA from the LCS with aortic dissection (AD). Considering the risk of dissection rupture and SCD, an emergency surgery of aortic replacement and coronary anomaly correction was performed successfully for the patient. This report illustrated that AAORCA complicated with acute AD (AAD) is lethal and may promote the occurrence of coronary ischemia or sudden death by a new “double-kill” mechanism that myocardial ischemia was based on the extent of a fixed and a dynamic component like slit-like ostium, proximal narrowing, acute take-off angle and intramural course with the elliptic vessel shape. There is no doubt that surgery is the best treatment option for the AAORCA with AAD.

Individualized prediction of risk of ascending aortic syndromes

Objectives

Although ascending aortic diameter changes acutely after dissection, recommendation for prophylactic surgery of thoracic aortic aneurysms rely on data from dissected aortas. In this case-control study we aim to identify risk markers for acute and chronic aortic syndromes of the ascending aorta (ACAS-AA). Furthermore, to develop a predictive model for ACAS-AA.

Methods

We collected data of 188 cases of ACAS-AA and 376 controls standardized to age- and sex of the background population. Medical history and CT-derived aortic morphology were collected. For the dependent outcome ACAS-AA, potential independent risk factors were identified by univariate logistic regression and confirmed in multivariate logistic regression. As post-dissection tubular ascending aortic diameter is prone to expand, this factor was not included in the first model. The individual calculated adjusted odds ratios were then used in ROC-curve analysis to evaluate the diagnostic accuracy of the model. To test the influence of post-ACAS-AA tubular ascending aortic diameter, this was added to the model.

Results

The following risk factors were identified as independent risk factors for ACAS-AA in multivariate analysis: bicuspid aortic valve (OR 20.41, p = 0.03), renal insufficiency (OR 2.9, p<0.01), infrarenal abdominal aortic diameter (OR 1.08, p<0.01), left common carotid artery diameter (OR 1.40, p<0.01) and aortic width (OR 1.07, p<0.01). Area under the curve was 0.88 (p<0.01). Adding post-ACAS-AA tubular ascending aortic diameter to the model, negated the association of bicuspid aortic valve, renal insufficiency, and left common carotid artery diameter. Area under the curve changed to 0.98 (p<0.01).

Conclusions

A high performing predictive model for ACAS-AA, free of ascending aortic diameter, can be achieved. Furthermore, we have identified abdominal aortic ectasia as an independent risk factor of ACAS-AA. Integration of potential biomarkers and morphologic variables, derived from undissected aortas, would probably improve the model.

Bovine Aortic Arch: A Result of Chance or Mandate of Inheritance?

Previous studies have shown that bovine arch incidence is higher in patients with thoracic aortic aneurysms than in patients without an aneurysm. Although thoracic aortic aneurysm disease is known to be familial in some cases, it remains unknown if bovine arch results from a genetic mutation, thus allowing it to be inherited. Our objective was to determine the heritability of bovine arch from phenotypic pedigrees. We identified 24 probands from an institutional database of 202 living patients with bovine arch who had previously been diagnosed with thoracic aortic aneurysm and who had family members with previous chest computed tomography or magnetic resonance imaging scans. Aortic arch configuration of all first-degree and second-degree relatives was determined from available scans. Heritability of bovine arch was estimated using maximum-likelihood-based variance decomposition methodology implemented by way of the SOLAR package (University of Maryland, Catonsville, Maryland). 43 relatives of 24 probands with bovine arch had preexisting imaging available for review. The prevalence of bovine arch in relatives with chest imaging was 53% (n = 23) and did not differ significantly by gender (male: 64.3%, female: 55.6%, p = 1). The bovine arch was shown to be highly heritable with a heritability estimate (h2) of 0.71 (p = 0.048). In conclusion, the high heritability of bovine arch in our sample population suggests a genetic basis.

Transposition of left subclavian artery with reimplantation of isolated left vertebral artery before thoracic endovascular aneurysm repair for type B aortic dissection

Understanding and recognizing anatomic anomalies of the aortic arch is important when planning extra-anatomic debranching before thoracic endovascular aortic repair. A rare anomaly is the left vertebral artery aberrantly arising from the aortic arch; found in ∼5% of adults. When present, the artery courses through the carotid sheath at a variable length before entering the third or fourth cervical transverse foramen. In the present report, we have described the case of a 49-year-old man with a symptomatic, enlarging type B aortic dissection with an aberrant left vertebral artery and the novel methods used to surgically correct his pathology.

Evaluation of aortic arch morphologies by computed tomographic angiography in Turkish population

Background: The aim of this study was to evaluate the aortic arch morphologies in the Turkish population using the computed tomography angiography technique.

Methods: Between August 2009 and August 2019, a total of 2,037 (1,003 males, 1,034 females; mean age: 52.8±20.3 years; range, 3 months to 100 years) thoracic computed tomography angiography scans were retrospectively analyzed. The findings were classified as described previously in the literature. The prevalence of aortic arch morphologies and possible relationship with sex were analyzed. The prevalence of variations reported in previous studies was compared with the current study.

Results: The normal aortic arch pattern (type A), observed in 1,562 cases (76.7%), was determined statistically significantly more in males than females (p<0.05). The most common variation, bovine aortic arch (type B1) which observed in a total of 315 cases (15.5%), was determined statistically significantly more in females than males (p<0.05). The second most frequent variation, in which the left vertebral artery originates directly from the aortic arch (type C1) was detected in 97 cases (4.7%). There was also observed to be aberrant right subclavian artery in 21 cases (1%), right-sided aortic arch variation in seven cases (0.4%), and double aortic arch anomaly in four cases (0.1%). In terms of the reported frequency of type B variation, a significant difference was determined between the current and previous studies in Türkiye (p<0.05).

Conclusion: With the largest sample size to date, this study provides comparative information about the prevalence of aortic arch patterns in the Turkish population.

Prenatal Diagnosis of Bovine Aortic Arch Anatomic Variant

Fetal aortic arch development is an early and complex process that depends on many genetic and environmental factors. The final aortic arch varies greatly; it may take the form of a normal arch, anatomic variant (AAAV) with a common origin to that of the innominate artery and left common carotid artery (formerly known as “bovine aortic arch” (with an incidence of up to 27%)) or one of multiple pathological conditions. The present study aimed to establish the feasibility and impact of prenatal anatomic arch variants’ diagnosis. A retrospective study of 271 fetal second- and third-trimester anomaly scans was performed in our tertiary center. Examinations that evaluated the sagittal aortic arch were included and the branching pattern was assessed. Additionally, a literature data search based on the terms “common origin of innominate artery and left common carotid artery”, “bovine arch”, “bovine aortic” and “aortic arch anomalies” was performed. Results that referred to prenatal AAAV were retained and the papers evaluated. In our study, the AAA incidence was 1.93%, with 4 out of 5 cases being arch type B. All cases had minor associated conditions but a good postnatal outcome. An anatomic aortic variant with a common IA and LCCa prenatal diagnosis was found in a small number of studies; most of the cases described in pediatric and adult series were related to cardiac surgery for stenting, aneurysm or thoracic-associated diseases. The incidence of AAAV varied from 6 to 27% depending on the population studied (highest incidence in African individuals). The variant was highly associated with aortic dissection, pulmonary and cerebral embolism and increased risks of incidents during surgery. Diagnosing AAAV during a routine anatomic scan is feasible and diagnoses can be made when anomaly scans are performed. Awareness of the condition is important for postnatal surgery when other cardiac anomalies are found; this can prevent accidents with simple changes to the patient’s lifestyle, and, in the case of surgery, means we can adopt the correct surgical approach.

Prevalence of common origin of the innominate and left carotid artery (CILCA) or bovine arch configuration in patients with blunt aortic injury

BACKGROUND

The common origin of the innominate and left carotid artery (CILCA) have been described as a risk factor for thoracic aortic diseases (dissections and aneurysms), but its relationship with traumatic pathology of the thoracic aorta is not so well known. The aim of the present study is to describe the prevalence of CILCA among patients admitted to the hospital for high-energy polytrauma with aortic injury (BTAI) compared with a control group.

METHODS

Retrospective unicenter case-control study. Cases included all patients treated with BTAI between 1999-2020. The group of controls was patients admitted in our center for high-energy polytrauma between 2012-2017. Primary endpoint was to define the prevalence of CILCA among both groups and secondary endpoint was to measure the distance between brachiocephalic trunk (BCT) or left common carotid artery (LCCA) and left subclavian artery (LSA). Results were retrospectively reviewed by two investigators.

RESULTS

49 patients in BTAI group and 248 patients in control group. With a good concordance between investigators, 21 patients with CILCA (42.9%) in the BTAI group versus 61 CILCA (24.6%) in the control group (p=0.009). The mean distance between BCT/LCCA and LSA among the cases with CILCA was 10.09 mm (SD = 2.89) and 7.48 mm (SD = 3.65) among cases with standard aortic arch (p = 0.010).

CONCLUSIONS

In the present study we found that CILCA configuration is more prevalent in patients with BTAI and the distance to left subclavian artery is longer.

Frozen Elephant Trunk Repair for Acute Type A Dissection in Right Aortic Arch

A 68-year-old woman with right aortic arch and aberrant left subclavian artery was urgently operated for type A aortic dissection. Surgical management included total arch repair with frozen elephant trunk technique and left subclavian artery re-implantation. Post-operative course was complicated by severe renal failure, delirium and pneumonia. She was re-operated 3 weeks later due to an expanding proximal aortic anastomosis pseudoaneurysm. Right aortic arch is a rare vascular anomaly requiring thoughtful preoperative planning for adequate myocardial, cerebral and spinal protection. Frozen elephant trunk facilitates management of extensive dissection, relieves malperfusion and may alleviate the need for subsequent operations.

Aortic arch variant with a common origin of the innominate and left carotid artery as a determinant of thoracic aortic disease: a systematic review and meta-analysis

The aim of this study was to investigate whether the 'bovine' arch [i.e. arch variant with a common origin of the innominate and left carotid artery (CILCA)] is associated with an increased risk of thoracic aortic disease (TAD). The study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The PubMed, EMBASE and Cochrane databases were searched to identify all case series reporting about CILCA arch and TAD between January 2008 and December 2018. A total of 485 studies were screened. The prevalence of CILCA arch was assessed, and data analysis was performed considering the difference in the risk of TAD for presence versus absence of CILCA arch. Eight studies enrolling 11 381 subjects were retrieved for quantitative analysis. The proportion of TAD among CILCA arch patients was higher [41.5% (28.1-56.4)] than the proportion among patients with standard arch configuration 34.0% (20.1-51.4). The odds ratio of developing TAD was 1.4 times higher in subjects with CILCA arch (95% confidence interval 1.068-1.839). The test for an overall effect indicated a significant association between CILCA arch and TAD (P < 0.015). The I2 was 78.1% with a value of P < 0.001 for heterogeneity. The Egger test did not show evidence of publication bias (P = 0.317). In conclusion, our meta-analysis supports the hypothesis of a correlation between the presence of CILCA arch and the onset of TAD. Our results warrant a specific and long-term surveillance for patients with this anatomical variant, and a thorough awareness of its potential clinical implications during image interpretation.

Variants of the aortic arch in adult general population and their association with thoracic aortic aneurysm disease

BACKGROUND

Query a single institution computed tomography (CT) database to assess the prevalence of aortic arch anomalies in general adult population and their potential association with thoracic aortopathies.

METHODS

CT chest scan reports of patients aged 50-85 years old performed for any indication at a single health system between 2013 and 2016 were included in the analysis. Characteristics of patients with and without aortic arch anomalies were compared by t test and Fisher exact tests. Logistic regression analysis was performed to assess for independent risk factors of thoracic aortic aneurysm (TAA).

RESULTS

Of 21,336 CT scans, 603 (2.8%) described arch anomalies. Bovine arch (n = 354, 58.7%) was the most common diagnosis. Patients with arch anomalies were more likely to be female (p < .001), non-Caucasian(p < .001), and hypertensive (p < .001). Prevalence of TAA in arch anomalies group was 10.8% (n = 65) compared to 4.1% (n = 844) in the nonarch anomaly cohort (p < .001). The highest prevalence of thoracic aneurysm was associated with right-sided arch combined with aberrant left subclavian configuration (33%), followed by bovine arch (13%), and aberrant right subclavian artery (8.2%). On binary logistic regression, arch anomaly (OR = 2.85 [2.16-3.75]), aortic valve pathology (OR 2.93 [2.31-3.73]), male sex (OR 2.38 [2.01-2.80]), and hypertension (OR 1.47 [1.25-1.73]) were significantly associated with increased risk of thoracic aneurysm disease.

CONCLUSIONS

Reported prevalence of aortic arch anomalies by CT imaging in the older adult population is approximately 3%, with high association of TAA (OR = 2.85) incidence in this subgroup. This may warrant a more tailored surveillance strategy for aneurysm disease in this subpopulation.

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

INTRODUCTION

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".

METHODS

A systematic online search of PubMed and Google books databases was performed only in cadaveric studies.

RESULTS

Twenty studies with typical (78% prevalence) and variable (22%) branching patterns were included. Types 3b, 2b, 4b, 1b and 5b had a prevalence of 81%, of 13%, of 5%, 0% and of 0%, 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).

CONCLUSION

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.

Bovine aortic arch: Prevalence in human fetuses

OBJECTIVE

"Bovine aortic arch" is the second most common variant of aortic arch branching, in which only two branches originate directly from the aorta. The prevalence of this condition has been reported in different studies to be around 6% in human fetuses and 11-27% in the adult population. In this study, we describe the prevalence of bovine aortic arch in fetuses, and assess the prevalence of concomitant fetal anomalies.

METHODS

A retrospective analysis of 417 fetuses between 15-40 weeks of gestation. Data regarding branching of the fetal aortic arch and other fetal anomalies were collected by fetal echocardiography and/or fetal ultrasonography.

RESULTS

A bovine arch was found in 20/413 fetuses (4.8%, 95CI 3.1-7.3%), of whom 14/310 (4.5%) had no fetal anomalies, and 6/77 (7.8%) exhibited minor changes (P = .241). None of the 26 fetuses with major anomalies had a bovine arch.

CONCLUSION

Fetuses in this study had a lower prevalence of bovine aortic arch than that previously reported in adults, most probably due to differences in the population examined. This study was underpowered to determine that bovine arch is a common anatomic variant, and is not associated with fetal anomalies.

Geometric Pattern of Proximal Landing Zones for Thoracic Endovascular Aortic Repair in the Bovine Arch Variant

OBJECTIVE

The aim was to investigate whether the "bovine" aortic arch (i.e. arch variant with a common origin of the innominate and left carotid artery (CILCA)) is associated with a consistent geometric configuration of proximal landing zones for thoracic endovascular aortic repair (TEVAR).

METHODS

Anonymised thoracic computed tomography (CT) scans of healthy aortas were reviewed to retrieve 100 cases of CILCA. Suitable cases were stratified according to type 1 and 2 CILCA, and also based on type of arch (I, II, and III). Further processing allowed calculation of angulation and tortuosity of the proximal landing zones. Centre lumen line lengths of each proximal landing zone were measured in a view perpendicular to the centre line. All geometric features were compared with those measured in healthy patients with a standard arch configuration (n = 60). Two senior authors independently evaluated the CT scans, and intra- and interobserver repeatability were assessed.

RESULTS

The 100 selected patients (63% male) were 71.4 ± 7.7 years old. Type 1 CILCA (62/100) was more prevalent than type 2 CILCA (38/100), and the two groups were comparable in age (p = .11). Zone 3 presented a severe angulation (i.e. > 60°), which was greater than in Zone 2 (p < .001), and a consistently greater tortuosity than Zone 2 (p = .003). This pattern did not differ between type 1 and type 2 CILCA. A greater tortuosity was also observed in Zone 0, which was related to increased elongation of the ascending aorta (i.e. Zone 0), than the standard configuration. The CILCA had an overall greater elongation, and Zone 2 also was specifically longer. When stratifying by type of arch, reversely from Type III to Type I, the CILCA presented a gradual flattening of its transverse tract, which entailed a consistent progressive elongation (p = .03) and kinking of the ascending aorta, with a significant increase of Zone 0 angulation to even a severe degree (p = .001). Also, from Type III to Type I, Zone 2 presented a progressively shorter length (p = .004), which was associated with increased tortuosity (p < .05). Mean intra- and interobserver differences for angulation measurements were 1.4° ± 6.8° (p = .17) and 2.0° ± 10.1° (p = .19), respectively.

CONCLUSION

CILCA presents a consistent and peculiar geometric pattern compared with standard arch configuration, which provides relevant information for TEVAR planning, and may have prognostic implications.

The so-called "bovine aortic arch": a possible biomarker for embolic strokes?

PURPOSE

To examine the prevalence of the so-called bovine aortic arch variation (common origin of the brachiocephalic trunk and the left common carotid artery) in embolic stroke patients, compared with a control group.

METHODS

Aortic arch branching patterns were retrospectively evaluated in 474 individuals with (n = 152) and without (n = 322) acute embolic stroke of the anterior circulation. Contrast-enhanced CT scans of the chest and neck (arterial contrast phase, 1-2-mm slice thickness) were used to evaluate aortic arch anatomy. The stroke cohort included 152 patients who were treated for embolic strokes of the anterior circulation between 2008 and 2018. A total of 322 randomly selected patients who had received thoracic CT angiographies within the same time frame were included as a control group.

RESULTS

With a prevalence of 25.7%, the bovine aortic arch variant was significantly more common among patients suffering from embolic strokes, compared with 17.1% of control patients (p = 0.039, OR = 1.67, 95%CI = 1.05-1.97). Stroke patients were more likely to show the bovine arch subtype B (left common carotid artery originating from the brachiocephalic trunk instead of the aortic arch) (10.5% vs. 5.0%, p = 0.039, OR = 2.25, 95%CI = 1.09-4.63), while subtype A (V-shaped common aortic origin of the brachiocephalic trunk and the left carotid) was similarly common in both groups. There was no significant difference regarding the frequency of other commonly observed variant branching patterns of the aortic arch.

CONCLUSION

The bovine aortic arch, particularly the bovine arch subtype B, was significantly more common among embolic stroke patients. This might be due to altered hemodynamic properties within the bovine arch.

Prevalence and Types of Aortic Arch Variants and Anomalies in Congenital Heart Diseases

RATIONALE AND OBJECTIVES

Aortic arch (AA) variants and anomalies are important to recognize in patients with congenital heart disease (CHD) before surgery or intervention. The aim was to study the prevalence of AA anomalies and variants in patients with CHD compared to a control group. The secondary outcome was to report the associations between common variations of AA and specific types of CHD.

MATERIALS AND METHODS

After institutional review board approval, computed tomography studies of 352 CHD patients and control group of 400 consecutive computed tomography scans of the thorax were evaluated. The AA was assigned to one of seven common types, and their distribution was compared between CHD and control. The distribution of the AA anomalies and variants was evaluated as regard specific types of CHD and the visceroatrial situs.

RESULTS

Normal three-vessel branching pattern was the commonest in both groups, but was present in only 50.5% in the CHD compared to 68.5% in the control group, p < 0.00001. Right AA and aberrant right subclavian artery were significantly more common in CHD than control group (18.1% versus 0.25%, p < 0.00001) and (4.5% versus 0.25%, p = 0.0001), respectively. Direct aortic origin of left vertebral artery was insignificantly more common in CHD group (4.2% versus 2.7%, p = 0.258). Brachiobicephalic trunk was significantly more common in control than CHD group (27.7% versus 19.3%, p = 0.007).

CONCLUSION

Normal three-vessel AA was significantly less common in CHD. AA anomalies (right arch and aberrant right subclavian) were more common in CHD than control, while AA variants (brachiobicephalic trunk and direct aortic origin of left vertebral artery) were not.

Transposition of the left vertebral artery during endovascular stent-graft repair of the aortic arch

OBJECTIVES

The aim of this study was to present our experience with the management of isolated left vertebral artery during hybrid aortic arch repairs with thoracic endovascular aortic repair completion.

METHODS

This is a single-center, observational, cohort study. Between January 2007 and December 2018, 9 patients (4.5%) of 200 who underwent thoracic endovascular aortic repair were identified with isolated left vertebral artery. The isolated left vertebral artery was the dominant vertebral artery in 4 cases and entered the Circle of Willis to form the basilar artery in all cases. Isolated left vertebral artery transposition was performed in 2 patients during open ascending/arch repair before thoracic endovascular aortic repair completion. In 4 patients, isolated left vertebral artery transposition was performed concomitant with carotid-subclavian bypass during thoracic endovascular aortic repair completion ("zone 2" thoracic endovascular aortic repair). Primary outcomes were early (<30 days) and late survival, freedom from aortic-related mortality, and isolated left vertebral artery patency.

RESULTS

Primary technical success was achieved in all cases. Isolated left vertebral artery-related complication occurred in 1 patient (Horner syndrome). Immediate thrombosis, vagus/recurrent laryngeal nerve palsy, lymphocele, and chylothorax were never observed. Postoperative cerebrovascular accident or spinal cord injury was not observed. Median follow-up was 15 months (range, 3-72). We did not observe aortic-related mortality during the follow-up. Aortic-related intervention was never required. Both isolated left vertebral artery and carotid-subclavian bypass are still patent in all patients with no sign of anastomotic pseudoaneurysm or stenosis.

CONCLUSIONS

Although isolated left vertebral artery is not a frequent occurrence, it is not so rare. It may pose additional difficulties during hybrid aortic arch surgical repairs, but isolated left vertebral artery transposition was feasible, safe, and a durable reconstruction.

Simple renal cysts and bovine aortic arch: markers for aortic disease

Objective

This study aimed to assess the prevalence of thoracic aortic disease (TAD) and abdominal aortic aneurysms (AAA) among patients with simple renal cyst (SRC) and bovine aortic arch (BAA).

Methods

Through a retrospective search for patients who underwent both chest and abdominal CT imaging at our institution from 2012 to 2016, we identified patients with SRC and BAA and propensity score matched them to those without these features by age, gender and presence of hypertension, hyperlipidaemia, diabetes and chronic kidney disease.

Results

Of a total of 35 498 patients, 6366 were found to have SRC. Compared with the matched population without SRC, individuals with SRC were significantly more likely to have TAD (10.1% vs 3.9%), ascending aortic aneurysm (8.0% vs 3.2%), descending aortic aneurysm (3.3% vs 0.9%), type A aortic dissection (0.6% vs 0.2%), type B aortic dissection (1.1% vs 0.3%) and AAA (7.9% vs 3.3%). The 920 patients identified with BAA were significantly more likely to have TAD (21.8% vs 4.5%), ascending aortic aneurysm (18.4% vs 3.2%), descending aortic aneurysm (6.5% vs 2.0%), type A aortic dissection (1.4% vs 0.4%) and type B aortic dissection (2.4% vs 0.7%) than the matched population without BAA. SRC and BAA were found to be significantly associated with the presence of TAD (OR=2.57 and 7.69, respectively) and AAA (OR=2.81 and 2.56, respectively) on multivariable analysis.

Conclusions

This study establishes a substantial increased prevalence of aortic disease among patients with SRC and BAA. SRC and BAA should be considered markers for aortic aneurysm development.

Anatomical variations of aortic arch vessels in Japanese patients with aortic arch disease

OBJECTIVES

The present study analyzed the prevalence of variations of the aortic arch branching in Japanese population, comparing patients with aortic arch disease with healthy controls.

METHODS

Between from October 1999 and December 2015, 815 Japanese patients with aortic arch disease defined as aortic arch aneurysm (diameter ≥ 45 mm) and aortic dissection (group A) underwent aortic arch surgery in our institution. As a control group, 1506 traumatic screened patients were enrolled (group C).

RESULTS

Aortic arch anomaly was diagnosed in 140 patients (17.2%) in the group A and in 222 patients (14.7%) in the group C (p = 0.125). Significant differences were found in the incidence of aberrant subclavian artery (A: 14 patients, 1.7%, vs. C: 8 patients, 0.5%, p = 0.006). Significantly more patients with aortic arch aneurysm in the group A had anomalies of the aortic arch compared with the group C (p = 0.009), including bovine aortic arch (p = 0.049) and aberrant subclavian artery (p < 0.001). In term of aneurysm location, bovine arch was detected in more patients with proximal arch aneurysm (15.7%, p = 0.043), whereas aberrant subclavian artery was in more patients with distal location (3.7%, p < 0.001). No difference was found in aortic arch anomaly in patients with acute or chronic dissection.

CONCLUSION

Aberrant subclavian artery was a significant maker of aortic arch disease in Japanese populations. Bovine arch was a risk maker of proximal arch aneurysm, and aberrant subclavian artery was a risk factor of distal arch aneurysm.

Case Series of Aortic Arch Aneurysm in Patients with Bovine Arch Treated with Proximal Scalloped and Fenestrated Stent Graft

PURPOSE

The bovine arch is the most common variant of the aortic arch and occurs when the innominate artery shares a common origin with the left common carotid artery. We report an endovascular repair of aortic arch aneurysm in patients with a bovine arch using the Najuta proximal scalloped and fenestrated stent graft.

MATERIALS AND METHODS

Thoracic endovascular aneurysm repairs using the Najuta stent graft were performed at our facility. It was inserted and deployed at a zone 0 with precise positional adjustment of the scallop of the stent graft to the brachiocephalic trunk.

RESULTS

Overall, eight patients with bovine aortic arch were treated with fenestrated endovascular aneurysm repair. Technical success was 100% with no 30-day death. The follow-up period ranged from 7 to 29 (median 12) months. None of the patients had a stroke or paraplegia, and no endoleak was observed. All brachiocephalic trunks scalloped, and the left subclavian artery fenestrated vessels remained patent during the follow-up period.

CONCLUSION

The Najuta stent graft repair of aortic arch aneurysms in patients with a bovine arch is a safe and effective treatment option, with good immediate and short-term results.

Association of variant arch anatomy with type B aortic dissection and hemodynamic mechanisms

OBJECTIVE

Congenital aortic arch variations are more common in patients with thoracic aortic disease for reasons unknown. Additionally, little is understood about their relation to type B aortic dissections (TBAD) specifically. We investigated the prevalence of variant aortic arch anatomy in patients with TBAD compared with controls. To understand the implications of how variant aortic arch anatomy may contribute to degenerative aortic disease, we compared flow hemodynamics of three variations of aortic arches using four-dimensional flow magnetic resonance imaging (4D flow MRI).

METHODS

Arch anatomy on computed tomography imaging was reviewed and compared between patients with TBAD and age/sex-matched controls free of aortic pathology. Arch variants were defined as follows: common origin of innominate and left common carotid artery (bovine arch), aberrant right subclavian artery, and right-sided aortic arch. Demographics, TBAD characteristics, and follow-up data were abstracted. Patients with TBAD with variant and conventional aortic arches were compared. Additionally, three matched healthy controls with conventional, bovine, and aberrant right subclavian artery arches underwent 4D flow MRI evaluation to assess if there were differences in flow patterns by arch type. Indices of regional hemodynamic wall sheer stress were compared.

RESULTS

Computed tomography scans of 185 patients with TBAD (mean age, 58.1 ± 12.4 years; 72.4% males; 71.4% Caucasian) and 367 controls (mean age, 62.5 ± 13.4 years; 67% males; 77.9% Caucasian) were reviewed. Variant arch anatomy was more prevalent in patients with TBAD (40.5% vs 24.5%; P < .001). In patients with TBAD, there were no differences in the mean age of presentation and descending thoracic aorta diameter among those with variant or conventional arch anatomy. Patients with TBAD with variant arch anatomy had a higher percentage of dissection related thoracic aortic repairs (54.7% vs 33.6%; P = .004) with repairs occurring predominantly in the acute phase. 4D flow MRI demonstrated a higher systolic wall shear stress along the inner curve of the bovine arch compared with the conventional aberrant right subclavian artery arches.

CONCLUSIONS

Variant aortic arch anatomy is significantly more prevalent in patients with TBAD. patients with TBAD with variant arch anatomy had a higher percentage of dissection-related aortic repair. Preliminary 4D flow MRI data show differences in hemodynamic flow patterns between variant and conventional arches. Studies of long-term outcomes based on arch anatomy may offer additional insight to TBAD genesis and possibly influence management decisions.

Recurrent Aortic Dissection in a Patient With an Actin Mutation Treated With a Laser-Fenestrated Aortic Arch Stent-Graft

A 58-year-old African American female, who had previously undergone a valve-sparing aortic root replacement for a type A dissection, represented 2 months later with a new focal dissection and aneurysm with intramural hematoma just distal to the origin of the left subclavian artery. Since no landing zone distal to the subclavian artery existed, the patient underwent thoracic endovascular aortic repair with laser fenestration-aided stent-graft placement in the left subclavian artery. The patient recovered without complication, and 52 months later, she is doing well with normal renal function and ambulatory status.

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

OBJECTIVE/BACKGROUND

To investigate the prevalence of bovine arch (BA) among patients with type A and B aortic dissection, and to provide insight into the implication of this variation on the outcome of patients with acute or subacute type B aortic dissection (a/sTBAD).

METHODS

This retrospective cohort analysis includes patients with a/sTBAD admitted between January 2006 and December 2016. Computed tomographic angiograms (CTAs) of patients referred because of type A aortic dissection were also re-evaluated with regard to the presence of BA. As a control group, 110 oncological patients who had undergone a chest CTA for disease staging during the study period were enrolled. A total of 154 patients with a/sTBAD and 168 with type A aortic dissection were identified during the study period.

RESULTS

An overall prevalence of 17.6% for BA variants was revealed. The comparison between patients with aortic dissection and the control group showed no statistically significant difference in BA prevalence (17.7% vs. 17.3%; p = 1.0). No statistically significant difference in BA prevalence was observed when comparing patients with type A aortic dissection with those with type B aortic dissection (16.6% vs. 18.8%; p = .66). During a median follow-up period of 27.8 months, 30 patients died. The mortality rate among patients presenting a BA variant was 34.5%, whereas among patients without, it was 16.0% (p = .04). Multivariate analysis revealed the presence of a BA as an independent predictor of mortality (adjusted odds ratio 3.4, 95% confidence interval 1.2-9.8).

CONCLUSION

The BA should be considered as a predictor of the outcome for patients with type B aortic dissection.

A systematic review and meta-analysis of variations in branching patterns of the adult aortic arch

OBJECTIVE

The aortic arch (AA) is the main conduit of the left side of the heart, providing a blood supply to the head, neck, and upper limbs. As it travels through the thorax, the pattern in which it gives off the branches to supply these structures can vary. Variations of these branching patterns have been studied; however, a study providing a comprehensive incidence of these variations has not yet been conducted. The objective of this study was to perform a meta-analysis of all the studies that report prevalence data on AA variants and to provide incidence data on the most common variants.

METHODS

A systematic search of online databases including PubMed, Embase, Scopus, ScienceDirect, Web of Science, SciELO, BIOSIS, and CNKI was performed for literature describing incidence of AA variations in adults. Studies including prevalence data on adult patients or cadavers were collected and their data analyzed.

RESULTS

A total of 51 articles were included (N = 23,882 arches). Seven of the most common variants were analyzed. The most common variants found included the classic branching pattern, defined as a brachiocephalic trunk, a left common carotid, and a left subclavian artery (80.9%); the bovine arch variant (13.6%); and the left vertebral artery variant (2.8%). Compared by geographic data, bovine arch variants were noted to have a prevalence as high as 26.8% in African populations.

CONCLUSIONS

Although patients who have an AA variant are often asymptomatic, they compose a significant portion of the population of patients and pose a greater risk of hemorrhage and ischemia during surgery in the thorax. Because of the possibility of encountering such variants, it is prudent for surgeons to consider potential variations in planning procedures, especially of an endovascular nature, in the thorax.

Outcomes After Operations for Unicuspid Aortic Valve With or Without Ascending Repair in Adults

BACKGROUND

Unicuspid aortic valve is an important subset of bicuspid aortic valve, and knowledge regarding its aortopathy pattern and surgical outcomes is limited. Our objectives were to characterize unicuspid aortic valve patients, associated aortopathy, and surgical outcomes.

METHODS

From January 1990 to May 2013, 149 adult unicuspid aortic valve patients underwent aortic valve replacement or repair for aortic stenosis (n = 13), regurgitation (n = 13), or both (n = 123), and in 91 (61%) the aortic valve operation was combined with aortic repair. Data were obtained from the Cardiovascular Information Registry and medical record review. Three-dimensional imaging analysis was performed from preoperative computed tomography and magnetic resonance imaging scans. The Kaplan-Meier method was used for survival analysis.

RESULTS

Patients had a mean maximum aortic diameter of 44 ± 8 mm and variably involved the aortic root, ascending, or arch, or both. Patients with valve operations alone were more likely to be hypertensive (p = 0.01) and to have severe aortic stenosis (p = 0.07) than those who underwent concurrent aortic operations. There were no operative deaths, strokes, or myocardial infarctions. Patients undergoing aortic repair had better long-term survival. Estimated survival at 1, 5, and 10 years was 100%, 100%, and 100% after combined operations and was 100%, 88%, and 88% after valve operations alone (p = 0.01).

CONCLUSIONS

Patients with a dysfunctional unicuspid aortic valve frequently present with an ascending aneurysm that requires repair. Combined aortic valve operations and aortic repair was associated with significantly better long-term survival than a valve operation alone. Further study of this association may direct decisions about timing of surgical intervention.

Incidence of branching patterns variations of the arch in aortic dissection in Chinese patients

Several authors have described anatomic variations of the aortic arch in 13% to 20% of the patients who do not have aortic disease. However, few studies have evaluated these patterns in the thoracic aortic dissection (TAD). In the authors' knowledge, this is the first survey that specifically investigates the frequency of these variations in a broad, nonselected group of Chinese patients with aortic dissection. Furthermore, it compares this group with a group of patients without aortic disease.The objective of this study was to define the variation frequency of the aortic arch branches pattern using the tomographic studies of 525 Chinese patients with a diagnosis of TAD. The Stanford classification was used to set the site of the initial tear of the dissection. In addition, we performed an epidemiological analysis of the aortic arch anatomic variations in TAD, and its possible implications for surgical or endovascular treatment. The general hypothesis proposal asserted that Chinese patients with dissection of the aorta have a similar incidence of variations of the aortic arch to the patients without aortic disease.A retrospective study of cases and controls was carried out using the tomographic studies (CT) of all patients admitted to the First Affiliated Hospital of Zhengzhou University, located at Henan-China, with a confirmed diagnosis of aortic dissection from January 2012 until December 2014. The group of cases consisted of 525 patients: 374 men and 151 women, with a mean age of 52.27 years (range, 20-89). The average age of the patients with Stanford A and B aortic dissection was 49.46 and 53.67, respectively. The control group consisted of 525 unselected patients without TAD who underwent a CT scan of the chest due to other indications. This group consisted of 286 men and 239 women, with a mean age of 53.60 years (range, 18-89). All the patients with aneurysm or dissection were excluded from the control group. We performed a statistical analysis of demographic data.The study found 7 different patterns of the aortic arch on both groups of cases and controls. Within the 525 patients with TAD were observed 85 (16.19%) anatomical variations, while the control group showed 112 variations (21.33%); P = 0.033. The most common anatomical variant was the bovine arch, found in 62 (11.80%) cases of TAD compared with 77 (14.66%) in the control group; P = 0.172. Anatomical variations were observed in 14.32% of the patients with Stanford A dissection and 17.09% of the patients with Stanford B dissection; P = 0.425. Patients with Stanford A dissection showed the pattern of bovine arch in 23 (13.21%) of 174 cases. In contrast, the patients with Stanford B dissection showed it in 39 (11.11%) of 351 cases; P = 0.481. The anatomical variant defined as vertebral artery of direct origin of the aortic arch was more frequent in the patients with Stanford B dissection (5.12%). The patients with Stanford A dissection presented this pattern in 1.14% of the cases; P = 0.025. This study observed an increased frequency of aortic dissection in the subgroup from 41 to 60 years old. In the subgroup from 41 to 60 years old without TAD, a greater frequency of anatomical variations were found than in the patients with TAD (20.81% vs 14.23%; P = 0.050). The same fashion was seen in patients older than 80 years (27.27% vs 0%; P = 0.030). The anatomical variations of the aortic arch with TAD occurred in 14.97% of the male patients and 19.20% of the female patients compared to 21.67% to 20.92% in the control group; P = 0.026 and P = 0.681, respectively.The aortic arch variations were found less frequently in the TAD group than in the control group in the present Chinese series. The bovine arch was considered the variant pattern of the major frequency in the patients with TAD and the control group. The anatomical variant of 4 branches, defined as vertebral artery of direct origin of the aortic arch, was more frequent in patients with Stanford B aortic dissection than in the patients with Stanford A.This finding might show an association between the geometry of the aortic arch and the site of onset of first intimal tear of dissection.

Aortic dissection associated with blunt chest trauma diagnosed by elevated D-dimer

INTRODUCTION

Similar to spontaneous aortic dissection, traumatic aortic dissection is diagnosed with a careful history and physical exam, chest radiograph, and ultimately, dedicated aortic imaging. The diagnosis of spontaneous aortic dissection may be aided by using the serum D-dimer test. The use of D-dimer for diagnosing aortic injury in the setting of blunt trauma has not previously been reported.

PRESENTATION OF CASE

We present a case of aortic dissection in a 61-year-old male diagnosed when the patient presented with chest pain after blunt chest trauma.

DISCUSSION

The patient had no known history or risk factors for aortic disease. None of the classic findings were present by history, physical examination or chest radiograph and the diagnosis was made as the result of an elevated D-dimer. We discuss how the D-dimer test fortuitously led to the diagnosis in this case, and the implications.

CONCLUSION

D-dimer could be helpful in diagnosing aortic injuries in low-risk chest trauma patients.

Patient-specific finite element analysis of ascending aorta aneurysms

Catastrophic ascending aorta aneurysm (AsAA) dissection and rupture can be prevented by elective surgical repair, but identifying individuals at risk remains a challenge. Typically the decision to operate is based primarily on the overall aneurysm size, which may not be a reliable indicator of risk. In this study, AsAA inflation and rupture was simulated in 27 patient-specific finite element models constructed from clinical CT imaging data and tissue mechanical testing data from matching patients. These patients included n = 8 with concomitant bicuspid aortic valve (BAV), n = 10 with bovine aortic arch (BAA), and n = 10 with neither BAV nor BAA. AsAA rupture risk was found to increase with elevated systolic wall stress and tissue stiffness. The aortic size index was sufficient for identifying the patients with the lowest risk of rupture, but unsuitable for delineating between patients at moderate and high risk. There was no correlation between BAV or BAA and AsAA rupture risk; however, the AsAA morphology was different among these patients. These results support the use of mechanical parameters such as vessel wall stress and tissue stiffness for AsAA presurgical evaluation.

Atypical aortic arch branching variants: A novel marker for thoracic aortic disease

OBJECTIVE

To examine the potential of aortic arch variants, specifically bovine aortic arch, isolated left vertebral artery, and aberrant right subclavian artery, as markers for thoracic aortic disease (TAD).

METHODS

We screened imaging data of 556 patients undergoing surgery due to TAD for presence of aortic arch variations. Demographic data were collected during chart review and compared with a historical control group of 4617 patients.

RESULTS

Out of 556 patients with TAD, 33.5% (186 patients) demonstrated anomalies of the aortic arch, compared with 18.2% in the control group (P < .001). Three hundred seventy (66.5%) had no anomaly of the aortic arch. Bovine aortic arch emerged as the most common anomalous branch pattern with a prevalence of 24.6% (n = 137). Thirty-five patients (6.3%) had an isolated left vertebral artery, and 10 patients (1.8%) had an aberrant right subclavian artery. When compared with the control group, all 3 arch variations showed significant higher prevalence in patients with TAD (P < .001). Patients with aortic aneurysms and anomalous branch patterns had hypertension less frequently (73.5% vs 81.8%; P = .048), but had a higher rate of bicuspid aortic valve (40.8% vs 30.6%; P = .042) when compared with patients with aneurysms but normal aortic arch anatomy. Patients with aortic branch variations were significantly younger (58.6 ± 13.7 years vs 62.4 ± 12.9 years; P = .002) and needed intervention for the aortic arch more frequently than patients with normal arch anatomy (46% vs 34.6%; P = .023).

CONCLUSIONS

Aortic arch variations are significantly more common in patients with TAD than in the general population. Atypical branching variants may warrant consideration as potential anatomic markers for future development of TAD.

Preoperative detection of anomalies of carotid arteries in the neck surgery

The aim of this study was to examine the course of the carotid artery (CA) and define CA anomalies important for neck surgery using conventional and three-dimensional computer tomography (3D CT). This was designed as an observational study with retrospective CT and 3D CT angiography analysis. 4,000 CAs depicted on 2,000 CT angiographies were analyzed to determine the relationship of common, internal, and external portions of the CA to the neck organs, with special emphasis on the thyroid gland area and organs involved in the neck dissection surgery. A total of 47 out of 4,000 imaged CAs had congenital anomalies (1.18%). These anomalies were found in 45 patients, unilaterally in 33 and bilaterally in two. The level of the common CA bifurcation to internal and external CAs was rarely abnormal. It was at the level of C5 and C6 in two cases only (0.05%). The common CA, either aberrant or tortuous, ran abnormally close to the thyroid gland in 22 cases (0.55%). In planning neck dissection surgery, laryngectomy, or thyroidectomy, the surgeon should bear in mind that CA anomalies are present in approximately 1.2% of cases. Preoperative conventional CT angiography or 3D CT allows precise identification of anomalous CAs, thereby reducing the possible risk of intraoperative injury.

An experimental study to replace the thoracic descending aorta for pigs with a self-made sutureless blood vessel

To simplify the procedure of blood vessel replacement operation and shorten the vascular anastomosis time, we developed a special artificial blood vessel which can be connected to native blood vessels without suture. The self-made sutureless blood vessel (SMSBV) was made from two titanium connectors and a Gore-Tex graft. To investigate blood compatibility and histocompatibility of the SMSBV, we carried thoracic descending aorta replacement using either SMSBV or Gore-Tex, respectively, in pigs. The aortic clamp time and the operative blood loss in the experimental group (using SMSBV) were less than those in the control group (using Gore-Tex). The whole blood hematocrit, platelet count, plasma soluble P-selectin, plasma free hemoglobin, and interleukins 2, 6 at each time point were not different significantly between the two groups. Light microscopy and transmission electron microscopy examination showed there were layers of vascular smooth muscle cells and endothelial cells adhered in the inner wall of artificial blood vessel without any signs of thrombosis. Based on the result, we have drawn the conclusion that the application of SMSBV can significantly shorten the vascular anastomosis time, reduce operative blood loss, and show good blood and tissue compatibility.