Epidemiology of thoracic aortic dissection

Gasdermin D deficiency attenuates development of ascending aortic dissections in a novel mouse model

Background

Thoracic aortic dissection (TAD) is a silent killer. Approximately two-thirds of the cases occur in the ascending aorta (i.e. type A dissection) and majority of them are unrelated to genetic mutations. However, animal models of spontaneous type A dissection are not widely available. In the present study, a novel mouse TAD model was created. Further, the role of gasdermin D (GSDMD) in TAD development was evaluated.

Methods

TADs were created by treating ascending aorta of adult mice (C57BL/6J) with active elastase (40.0 U/ml) and β-aminopropionitrile (Act E+BAPN). The temporal progress of the TAD pathology was rigorously characterized by histological evaluation and scanning electron microscopy, while potential mechanisms explored with bulk RNA sequencing of specimens collected at multiple timepoints. With this novel TAD model, further experiments were performed with Gsdmd -/- mice to evaluate its impact on TAD formation.

Results

The ascending aorta challenged with Act E+BAPN developed pathology characterized by an early onset of intimomedial tears (complete penetration) and intramural hematoma, followed by progressive medial loss and aortic dilation. Ingenuity Pathway Analysis and functional annotation of differentially expressed genes suggested that a unique inflammatory micro-environment, rather than general inflammation, promoted the onset of TADs by specifically recruiting neutrophils to the aortic wall, while the pathology at the advanced stage was driven by T-cell mediated immune injury. Gsdmd -/- attenuated medial loss, adventitial fibrosis, and dilation of TADs. This protective effect was associated with a reduced number of TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) positive cells and T-cells in TADs.

Conclusions

A novel mouse TAD model was created in the ascending aorta. It produces a unique microenvironment to activate different immune cell subsets, promoting onset and subsequent remodeling of TADs. Consistently, Gsdmd -/- attenuates TAD development, with modulation of cell death and T-cell response likely acting as the underlying mechanism.

Diagnosing aortic dissection: A review of this elusive, lethal diagnosis

Aortic dissection (AD) remains a difficult diagnosis in the emergency setting. Despite its rare occurrence, it is a life-threatening pathology that, if missed, is typically fatal. Previous studies have documented minimal improvement in timely and accurate diagnoses despite the advancement of computed tomography. Previous literature has highlighted aortic dissections as a major cause of serious misdiagnosis-related harm. The aim of this article is to review the available literature on AD, discussing the diversity in presentations and the prevalence of historical and exam features to better aid in the diagnosis of AD. AD remains a difficult diagnosis, even with the widespread prevalence of computed tomography angiography usage. No single feature of the history or physical examination is enough to raise suspicion. The diagnosis should be strongly considered in any patient with chest pain that is severe and unexplained by other findings or testing. Those who do not present with acute pain are often complicated by neurologic deficits, hypotension, or syncope. These patients suffer from a change in mental status limiting their ability to participate in the history and physical examination and have a higher rate of complications and mortality. An educated understanding of the atypical presentations of aortic dissection helps the clinician to realistically rank it on the differential diagnosis, culminating in judicious use of definitive imaging.

Biomimetic-Structured Cobalt Nanocatalyst Suppresses Aortic Dissection Progression by Catalytic Antioxidation

As one of the most lethal cardiovascular diseases, aortic dissection (AD) is initiated by overexpression of reactive oxygen species (ROS) in the aorta that damages the vascular structure and finally leads to massive hemorrhage and sudden death. Current drugs used in clinics for AD treatment fail to efficiently scavenge ROS to a large extent, presenting undesirable therapeutic effect. In this work, a nanocatalytic antioxidation concept has been proposed to elevate the therapeutic efficacy of AD by constructing a cobalt nanocatalyst with a biomimetic structure that can scavenge pathological ROS in an efficient and sustainable manner. Theoretical calculations demonstrate that the antioxidation reaction is catalyzed by the redox transition between hydroxocobalt(III) and oxo-hydroxocobalt(V) accompanied by inner-sphere proton-coupled two-electron transfer, forming a nonassociated activation catalytic cycle. The efficient antioxidation action of the biomimetic nanocatalyst in the AD region effectively alleviates oxidative stress, which further modulates the aortic inflammatory microenvironment by promoting phenotype transition of macrophages. Consequently, vascular smooth muscle cells are also protected from inflammation in the meantime, suppressing AD progression. This study provides a nanocatalytic antioxidation approach for the efficient treatment of AD and other cardiovascular diseases.

Activation of the alternative complement pathway modulates inflammation in thoracic aortic aneurysm/dissection

Thoracic aortic aneurysm/dissection (TAAD) is a lethal vascular disease, and several pathological factors participate in aortic medial degeneration. We previously discovered that the complement C3a-C3aR axis in smooth muscle cells promotes the development of thoracic aortic dissection (TAD) through regulation of matrix metalloproteinase 2. However, discerning the specific complement pathway that is activated and elucidating how inflammation of the aortic wall is initiated remain unknown. We ascertained that the plasma levels of C3a and C5a were significantly elevated in patients with TAD and that the levels of C3a, C4a, and C5a were higher in acute TAD than in chronic TAD. We also confirmed the activation of the complement in a TAD mouse model. Subsequently, knocking out Cfb (Cfb) or C4 in mice with TAD revealed that the alternative pathway and Cfb played a significant role in the TAD process. Activation of the alternative pathway led to generation of the anaphylatoxins C3a and C5a, and knocking out their receptors reduced the recruitment of inflammatory cells to the aortic wall. Moreover, we used serum from wild-type mice or recombinant mice Cfb as an exogenous source of Cfb to treat Cfb KO mice and observed that it exacerbated the onset and rupture of TAD. Finally, we knocked out Cfb in the FBN1C1041G/+ Marfan-syndrome mice and showed that the occurrence of TAA was reduced. In summary, the alternative complement pathway promoted the development of TAAD by recruiting infiltrating inflammatory cells. Targeting the alternative pathway may thus constitute a strategy for preventing the development of TAAD.NEW & NOTEWORTHY The alternative complement pathway promoted the development of TAAD by recruiting infiltrating inflammatory cells. Targeting the alternative pathway may thus constitute a strategy for preventing the development of TAAD.

Mapping microarchitectural degeneration in the dilated ascending aorta with ex vivo diffusion tensor imaging

Aims

Thoracic aortic aneurysms (TAAs) carry a risk of catastrophic dissection. Current strategies to evaluate this risk entail measuring aortic diameter but do not image medial degeneration, the cause of TAAs. We sought to determine if the advanced magnetic resonance imaging (MRI) acquisition strategy, diffusion tensor imaging (DTI), could delineate medial degeneration in the ascending thoracic aorta.

Methods and results

Porcine ascending aortas were subjected to enzyme microinjection, which yielded local aortic medial degeneration. These lesions were detected by DTI, using a 9.4 T MRI scanner, based on tensor disorientation, disrupted diffusion tracts, and altered DTI metrics. High-resolution spatial analysis revealed that fractional anisotropy positively correlated, and mean and radial diffusivity inversely correlated, with smooth muscle cell (SMC) and elastin content (P < 0.001 for all). Ten operatively harvested human ascending aorta samples (mean subject age 61.6 ± 13.3 years, diameter range 29-64 mm) showed medial pathology that was more diffuse and more complex. Nonetheless, DTI metrics within an aorta spatially correlated with SMC, elastin, and, especially, glycosaminoglycan (GAG) content. Moreover, there were inter-individual differences in slice-averaged DTI metrics. Glycosaminoglycan accumulation and elastin degradation were captured by reduced fractional anisotropy (R2 = 0.47, P = 0.043; R2 = 0.76, P = 0.002), with GAG accumulation also captured by increased mean diffusivity (R2 = 0.46, P = 0.045) and increased radial diffusivity (R2 = 0.60, P = 0.015).

Conclusion

Ex vivo high-field DTI can detect ascending aorta medial degeneration and can differentiate TAAs in accordance with their histopathology, especially elastin and GAG changes. This non-destructive window into aortic medial microstructure raises prospects for probing the risks of TAAs beyond lumen dimensions.

Genetic architecture of thoracic aortic dissection in the female population

BACKGROUND

Sex-related differences in cardiovascular disease are now gaining much more attention and their importance is increasingly being recognized, but little is known about the genetic distribution, genotype-phenotype correlation, and outcomes in the female population with thoracic aortic dissection (TAD).

METHODS

One hundred seventy-nine Chinese female probands with TAD were enrolled from Tongji Hospital between October 2009 and October 2020. Genetic analysis was performed among 12 genes, and participants were subsequently followed up for a median of 38.2 months for TAD-related death.

RESULTS

We identified 18 pathogenic or likely pathogenic variants among 18 (10.1%) probands and 21 variants of uncertain significance in 21 (11.7%) patients. Individuals with positive variants presented with a significant risk of TAD (OR: 12.0, 95% CI: 5.87-26.8), and an association between FBN1 (p = 2.60E-11, OR = 19.8), MYLK (p = 0.006, OR = 14.0) variants and an increased risk for female TAD was identified as well. Furthermore, nearly half of the variants were found in the FBN1 gene, which was significantly linked to early aortic dissection and tended to cause death at a young age.

CONCLUSION

This study revealed the monogenic contribution of known TAD genes to the female TAD population with East Asian ancestry. Patients who tested positive for FBN1 were significantly younger at the time of aortic dissection and had a higher probability of dying at an early age.

Current review of acute type A aortic dissection in Malaysia

Acute type A aortic dissection (ATAAD) still poses significant challenges and management dilemmas for cardiovascular surgeons worldwide. Despite the continuous improvement in diagnosis and management strategies for ATAAD, clinical outcomes remain poor and the optimal therapy is still debatable especially those with malperfusion syndrome (MPS). This review is based on the current literature and includes the results from the Aortic Registry of National Heart Institute of Malaysia (NHIM) database. It covers different aspects of ATAAD and concentrates on the outcome of surgical repair. The diagnosis is often delayed leading to variable outcomes. High index of suspicion and urgent treatment is required to tackle this dynamic disease which include the variation in presentation and clinical course. Different surgical techniques and perfusion strategies have been described to save patients. Complex techniques such as total arch replacement (TAR) with frozen elephant trunk and valve sparing root surgery may provide long-term benefit in selected patients, but require significant surgical expertise and experience.

Ascending thoracic aortic aneurysm size at presentation and growth by diameter

AIM

To investigate the hypothesis that lung cancer screening allows for earlier identification of ascending thoracic aortic aneurysms (aTAAs) and that growth rates for aTAAs are greatest at larger sizes.

MATERIALS AND METHODS

This single referral centre retrospective study manually gathered computed tomography (CT) data from 732 patients presenting from July 2002 to August 2022. Five hundred and seventeen patients with aTAA >39 mm were identified to compare presenting diameter by year of presentation. Four hundred and thirty-two patients had CT examinations >3 months apart, allowing for growth analysis. Patients were separated by initial examination date (before or after 12/31/2013) for presenting size comparison. Patients were then divided into five groups based on aTAA diameter for growth rate analysis.

RESULTS

At identification, patients had a median aTAA diameter of 44 mm (IQR 41-47 mm). Patients with aTAAs identified prior to December 2013 (n=129) had an average aTAA diameter 1.7 mm larger than those identified later (n=388; p=0.003). The growth analysis showed an average growth rate of 0.1 mm/year (p<0.001) across the entire cohort. Patients with an aTAA diameter of ≥55 mm (n=12) grew the fastest at 1.9 mm/year (p<0.001). In the <40 mm group (n=43), the aTAAs expanded at 0.2 mm/year, faster than the 0.1 mm/year of the slowest expanding 45-49 mm group (n=130; p=0.04).

CONCLUSION

aTAA size at discovery was larger before lung cancer screening guidelines took effect in December 2013. The largest aTAAs expanded fastest, but growth rates were slowest in the medium-sized 45-49 mm diameter group.

Sex-Related Differences After Proximal Aortic Surgery: Outcome Analysis of 1773 Consecutive Patients

BACKGROUND

Guidelines on the management of aortic aneurysm disease do not account for sex differences regarding surgical procedures on the proximal aorta, although faster aneurysm growth, increased rupture risk, and higher postoperative mortality have been found in women. We therefore analyzed outcome differences between men and women receiving operations on the proximal aorta.

METHODS

A total of 1773 patients underwent nonemergency surgical procedures on the aortic valve (AV) and proximal aorta at our institution between 2000 and 2018. Of these, 772 patients (21.8% women) received a Bentall procedure, 349 (20.3% women) had AV-sparing root replacement, and 652 (31.1% women) underwent AV and supracommissural ascending aorta replacement. Primary outcomes were in-hospital mortality and midterm survival.

RESULTS

When assessing sex-related differences within the entire group of patients that received an operation on the proximal aorta, women were found to be older, had a lower body mass index, and were smokers less often. Despite shorter procedural times, median ventilation times and intensive care unit length of stay were longer in women. In-house mortality was also higher in women (3.6% vs 0.9%, P < .001). Multivariable logistic regression revealed age (odds ratio [OR], 1.8; 95% CI, 1.4-2.3 per 5 years added; P < .001), female sex (OR, 2.6; 95% CI, 1.2-5.8; P = .02), and urgent surgery (OR, 3.1; 95% CI, 1.2-7.3; P = .01) as independent risk factors for in-house death. Midterm survival was lower for women in the entire cohort (P = .02) and particularly within the Bentall subgroup (P = .004).

CONCLUSIONS

Female sex is an independent risk factor for operative mortality in patients undergoing proximal aortic surgery but is currently not addressed in guidelines. More research should focus on etiology and prevention of these worse outcomes in female patients.

Biomechanical characterization of normal and pathological human ascending aortic tissues via biaxial testing Experiment, constitutive modeling and finite element analysis

BACKGROUND

Aortic dissection and atherosclerosis are two common pathological conditions affecting the aorta. Aortic biomechanics are believed to be closely associated with the pathological development of these diseases. However, the biomechanical environment that predisposes the aortic wall to these pathological conditions remains unclear.

METHODS

Sixteen ascending aortic specimens were harvested from 16 human subjects and further categorized into three groups according to their disease states: aortic dissection group, aortic dissection with accompanied atherosclerosis group and healthy group. Experimental stress-strain data from biaxial tensile testing were used to fit the anisotropic Mooney-Rivlin model to determine material parameters. Computed tomography images or transesophageal echocardiography images were collected to construct computational models to simulate the stress/strain distributions in aortas at the pre-dissection state. Statistical analyses were performed to identify the biomechanical factors to distinguish three groups of aortic tissues.

RESULTS

Material parameters of anisotropic Mooney-Rivlin model were fitted with average R2 value 0.9749. The aortic diameter showed no significant difference among three groups. Changes of maximum and average stress values from minimum pressure to maximum pressure (△MaxStress and △AveStress) had significantly difference between dissection group and dissection with accompanied atherosclerosis group (p = 0.0201 and 0.0102). Changes of maximum and average strain values from minimum pressure to maximum pressure (△MaxStrain and △AveStrain) from dissection group were significant different from healthy group (p = 0.0171 and 0.0281).

CONCLUSION

Changes of stress and strain values during the cardiac cycle are good biomechanical factors for predicting potential aortic dissection and aortic dissection accompanied with atherosclerosis.

Fate of the Patent False Lumen of the Descending Aorta After Surgical Treatment for Acute Type 1 Aortic Dissection

INTRODUCTION

This study aimed to investigate the factors affecting false lumen patency in the descending thoracic aorta among patients who underwent surgery for acute type 1 aortic dissection.

METHODS

A total of 112 patients with acute type 1 aortic dissection, with the flap below the diaphragm level, underwent surgery between January 2010 and September 2019. Of these, 60 patients who were followed up for ≥ 12 months and whose computed tomography scans were available were included in this study. The patients were divided into two groups: group I, consists of patent false lumen (n=36), and group II, consists of thrombosed false lumen (n=24). Demographic data, operative techniques, postoperative descending aortic diameters, reintervention, and late mortality were compared between the two groups.

RESULTS

The mean follow-up period of all patients was 37.6±26.1 months (range: 12-104). The diameter increase in the proximal and distal descending aorta was significantly higher in the patent false lumen group (5.3±3.7 mm vs. 3.25±2.34 mm; P=0.015; 3.1±2.52 mm vs. 1.9±1.55 mm; P=0.038, respectively). No significant difference in terms of hypertension was found between the two groups during the follow-up period (21 patients, 58.3% vs. 8 patients, 33.3%; P=0.058). A total of 29 patients (48.3%) were found to be hypertensive in the postoperative period.

CONCLUSION

After surgical treatment for acute type 1 aortic dissection, patients should be monitored closely, regardless of whether the false lumen is patent or thrombosed. Mortality and reintervention can be seen in patients with patent false lumen during follow-up.

Review article: Accuracy of emergency physician performed point-of-care ultrasound of the thoracic aorta: A systematic review and narrative synthesis of the literature

Point-of-care ultrasound (POCUS) is becoming ubiquitous in emergency medicine. POCUS for abdominal aortic aneurysm is well established in practice. The thoracic aorta can also be assessed by POCUS for dissection and aneurysm and transthoracic echocardiography is endorsed by international guidelines as an initial test for thoracic aortic pathologies. A systematic search of Ovid Medline, PubMed, EMBASE, SCOPUS and Web of Science from January 2000 to August 2022 identified four studies evaluating diagnostic accuracy of emergency physician POCUS for thoracic aortic dissection (TAD) and five studies for thoracic aortic aneurysm (TAA). Study designs were heterogeneous including differing diagnostic criteria for aortic pathology. Convenience recruitment was frequent in prospective studies. Sensitivity and specificity ranges for studies of TAD were 41-91% and 94-100%, respectively when an intimal flap was seen. Sensitivity and specificity ranges for studies of thoracic aorta dilation >40 mm were 50-100% and 93-100%, respectively; for >45 mm ranges were 64-65% and 95-99%. Literature review identified that POCUS is specific for TAD and TAA. POCUS reduces the time to diagnosis of thoracic aortic pathology; however, it remains insensitive and cannot be recommended as a stand-alone rule-out test. We suggest that detection of thoracic aorta dilation >40 mm by POCUS at any site increases the suspicion of serious aortic pathology. Studies incorporating algorithmic use of POCUS, Aortic Dissection Detection Risk Score and D-dimer as decision tools are promising and may improve current ED practices. Further research is warranted in this rapidly evolving field.

Effects of Age, Sex, and Extracellular Matrix Integrity on Aortic Dilatation and Rupture in a Mouse Model of Marfan Syndrome

BACKGROUND

Transmural failure of the aorta is responsible for substantial morbidity and mortality; it occurs when mechanical stress exceeds strength. The aortic root and ascending aorta are susceptible to dissection and rupture in Marfan syndrome, a connective tissue disorder characterized by a progressive reduction in elastic fiber integrity. Whereas competent elastic fibers endow the aorta with compliance and resilience, cross-linked collagen fibers confer stiffness and strength. We hypothesized that postnatal reductions in matrix cross-linking increase aortopathy when turnover rates are high.

METHODS

We combined ex vivo biaxial mechanical testing with multimodality histological examinations to quantify expected age- and sex-dependent structural vulnerability of the ascending aorta in Fbn1C1041G/+ Marfan versus wild-type mice without and with 4-week exposures to β-aminopropionitrile, an inhibitor of lysyl oxidase-mediated cross-linking of newly synthesized elastic and collagen fibers.

RESULTS

We found a strong β-aminopropionitrile-associated sexual dimorphism in aortic dilatation in Marfan mice and aortic rupture in wild-type mice, with dilatation correlating with compromised elastic fiber integrity and rupture correlating with compromised collagen fibril organization. A lower incidence of rupture of β-aminopropionitrile-exposed Marfan aortas associated with increased lysyl oxidase, suggesting a compensatory remodeling of collagen that slows disease progression in the otherwise compromised Fbn1C1041G/+ aorta.

CONCLUSIONS

Collagen fiber structure and function in the Marfan aorta are augmented, in part, by increased lysyl oxidase in female and especially male mice, which improves structural integrity, particularly via fibrils in the adventitia. Preserving or promoting collagen cross-linking may represent a therapeutic target for an otherwise vulnerable aorta.

Comparative Analysis of Morbidity and Mortality Outcomes in Elderly and Nonelderly Patients Undergoing Elective TEVAR: A Systematic Review and Meta-Analysis

OBJECTIVE

Due to an ever-increasing ageing population and limited available data around the use of thoracic endovascular aortic repair (TEVAR) in elderly patients, investigating its efficacy and safety in this age cohort is of vital importance. We thus reviewed the existing literature on this topic to assess the feasibility of TEVAR in elderly patients with severe thoracic aortic pathologies.

METHODS

We identified all original research studies that assessed TEVAR in elderly patients published up to 2023. Morbidity, as assessed by neurological and respiratory complications, endoleaks, and length of stay, was the primary endpoint. Short-term mortality and long-term survival were the secondary endpoints. The Mantel-Haenszel random and fixed effects methods were used to calculate the odds ratios for each outcome. Further sensitivity and subgroup analyses were performed to validate the outcomes.

RESULTS

Twelve original studies that evaluated elective TEVAR outcomes in elderly patients were identified. Seven studies directly compared the use of TEVAR between an older and a younger patient group. Apart from a shorter hospital stay in older patients, no statistically significant difference between the morbidity outcomes of the two different cohorts was found. Short-term mortality and long-term survival results favoured the younger population.

CONCLUSIONS

The present meta-analysis indicates that, due to a safe perioperative morbidity profile, TEVAR should not be contraindicated in patients based purely on old age. Further research using large patient registries to validate our findings in elderly patients with specific aortic pathologies and both elective and emergency procedures is necessary.

Serum Sema7A is increased in patients with acute aortic dissection

BACKGROUND

To observe the level of serum Sema7A in acute aortic dissection (AAD) and its diagnostic value for AAD.

RESEARCH DESIGN AND METHODS

Patients with sudden chest pain including AAD, acute myocardial infarction (AMI) or pulmonary embolism (PE) were enrolled. Patients without chest pain or cardiovascular diseases were included as the controls. Serum Sema7A and plasma D-dimer were detected and compared in each group.

RESULTS

85 AAD patients, 55 AMI patients, 15 PE patients, and 30 controls were enrolled. The concentration of Serum Sema7A in the AAD group was significantly higher than that in the control, AMI and PE group. Serum Sema7A was positively correlated with D-dimer. In AAD patients who underwent invasive intervention therapy, serum Sema7A levels were significantly decreased after the intervention. Serum Sema7A was an independent risk factor for the presence of AAD. The areas under the ROC curve of Sema7A and D-dimer for differential diagnosis of AAD from other chest pain disorders were 0.842 (0.776, 0.909) and 0.788 (0.714, 0.862), respectively.

CONCLUSIONS

Sema7A is highly expressed in patients with AAD. Sema7A might be a valuable biomarker for the early diagnosis of AAD and has the potential to differentiate AAD from AMI and PE.

Incidental Finding of Thoracic Aortic Dissection in a Patient Post-Coronary Artery Bypass Graft Surgery

Thoracic aortic dissection (TAD) is an uncommon but potentially fatal complication of coronary artery bypass graft (CABG). Most patients present to the emergency room with severe chest pain, shortness of breath, or after a syncopal episode. Asymptomatic patients pose a challenge to diagnosis. The authors present a case of an 82-year-old male, who was found to have an incidental finding of a 5-cm ascending aortic aneurysm with an intimal dissection flap four months after CABG. Extensive workup on possible risk factors such as underlying aortic diseases, genetic conditions, and hypertensive crisis proved noncontributory. Aggressive blood pressure control was achieved, and the patient was observed in the intensive care unit before discharge with follow-up. The purpose of this case report is to alert clinicians of TAD after CABG and highlight the importance of developing a protocol for follow-up and monitoring of patients who have undergone CABG, as complications can be asymptomatic. Early and accurate diagnosis of TAD as a complication of CABG is essential to improving survival rates.

Impact of wall displacements on the large-scale flow coherence in ascending aorta

In the context of aortic hemodynamics, uncertainties affecting blood flow simulations hamper their translational potential as supportive technology in clinics. Computational fluid dynamics (CFD) simulations under rigid-walls assumption are largely adopted, even though the aorta contributes markedly to the systemic compliance and is characterized by a complex motion. To account for personalized wall displacements in aortic hemodynamics simulations, the moving-boundary method (MBM) has been recently proposed as a computationally convenient strategy, although its implementation requires dynamic imaging acquisitions not always available in clinics. In this study we aim to clarify the real need for introducing aortic wall displacements in CFD simulations to accurately capture the large-scale flow structures in the healthy human ascending aorta (AAo). To do that, the impact of wall displacements is analyzed using subject-specific models where two CFD simulations are performed imposing (1) rigid walls, and (2) personalized wall displacements adopting a MBM, integrating dynamic CT imaging and a mesh morphing technique based on radial basis functions. The impact of wall displacements on AAo hemodynamics is analyzed in terms of large-scale flow patterns of physiological significance, namely axial blood flow coherence (quantified applying the Complex Networks theory), secondary flows, helical flow and wall shear stress (WSS). From the comparison with rigid-wall simulations, it emerges that wall displacements have a minor impact on the AAo large-scale axial flow, but they can affect secondary flows and WSS directional changes. Overall, helical flow topology is moderately affected by aortic wall displacements, whereas helicity intensity remains almost unchanged. We conclude that CFD simulations with rigid-wall assumption can be a valid approach to study large-scale aortic flows of physiological significance.

A Devastating Tear: Atypical Presentation of Aortic Dissection Discovered on Echocardiography

Acute aortic dissection (AAD) is a serious medical problem that requires prompt recognition in order to prevent deadly complications. Nevertheless, making the diagnosis can often be challenging. The clinical signs and symptoms of AAD may vary depending on the location of the dissection, leading to subtle differences in the initial patient presentation. Moreover, the classically described signs of blood pressure disparity, pulse deficit, or the presence of a diastolic murmur are often absent. Here, we report a challenging case of AAD in which the patient presented with acute substernal chest pain that resolved after a short period and was associated with hypotension. His bilateral upper and lower extremities were well perfused with symmetrical, palpable pulses. The initial point-of-care ultrasound (POCUS) showed a small pericardial effusion, and a follow-up echocardiogram revealed an ascending aortic flap with aortic root dilation diagnostic of AAD. Our aim is to shed light on the challenge of diagnosing AAD.

Risk factors for in-hospital death in 2,179 patients with acute aortic dissection

Background

This study aims to investigate the risk factors for in-hospital death in patients with acute aortic dissection (AAD) and to provide a straightforward prediction model to assist clinicians in determining the outcome of AAD patients.

Methods

Retrospective analysis was carried out on 2,179 patients admitted for AAD from March 5, 1999 to April 20, 2018 in Wuhan Union Hospital, China. The risk factors were investigated with univariate and multivariable logistic regression analysis.

Results

The patients were divided into two groups: Group A, 953patients (43.7%) with type A AAD; Group B, 1,226 patients (56.3%) with type B AAD. The overall in-hospital mortality rate was 20.3% (194/953) and 4% (50/1,226) in Group A and B respectively. The multivariable analysis included the variables that were statistically significant predictors of in-hospital death (P < 0.05). In Group A, hypotension (OR = 2.01, P = 0.001) and liver dysfunction (OR = 12.95, P < 0.001) were independent risk factors. Tachycardia (OR = 6.08, P < 0.001) and liver dysfunction (OR = 6.36, P < 0.05) were independent risk factors for Group B mortality. The risk factors of Group A were assigned a score equal to their coefficients, and the score of -0.5 was the best point of the risk prediction model. Based on this analysis, we derived a predictive model to help clinicians determine the prognosis of type A AAD patients.

Conclusions

This study investigate the independent factors associated with in-hospital death in patients with type A or B aortic dissection, respectively. In addition, we develop the prediction of the prognosis for type A patients and assist clinicians in choosing treatment strategies.

EphrinB2 promotes the human aortic smooth muscle cell growth and migration via mediating F-actin remodeling

OBJECTIVES

To evaluate the potential effect of EphrinB2 in human thoracic aortic dissection (TAD) and to illustrate the mechanisms governing the role of EphrinB2 in the growth of human aortic smooth muscle cells (HASMC).

METHODS

In the study, EphrinB2 expression was investigated by qRT-PCR and immunohistochemistry in 12 pairs of TAD and adjacent human tissues. HASMCs were used for in vitro experiments. Next, EphrinB2 overexpression and depletion in HASMCs were established by EphrinB2-overexpressing vectors and small interfering RNA, respectively. The transfection efficiency was evaluated by qRT-PCR and Western blot. The effects of overexpression and depletion of EphrinB2 on cell proliferation, migration, and invasion were tested in vitro. Cell Counting Kit-8, flow cytometry and transwell migration/invasion, and wound healing assay were used to explore the function of EphrinB2 on HASMC cell lines. The relationship between EphrinB2 and F-actin was assessed by Western blot, immunofluorescence, and Co-IP.

RESULTS

We found that EphrinB2 was a prognostic biomarker of TAD patients. Moreover, EphrinB2 expression negatively correlated to aortic dissection tissues, and disease incidence of males, suggesting that EphrinB2 might act as a TAD suppressor by promoting proliferation or decreasing apoptosis in HASMC. Next, over-expression of EphrinB2 in HASMC lines drove cell proliferation, migration, and invasion, and inhibited apoptosis while knockdown EphrinB2 showed the opposite phenomenon, respectively. Furthermore, the level of F-actin in mRNA, protein, and distribution in HASMC cell lines highly matched with the expression of EphrinB2, which indicated that EphrinB2 could mediate the HASMC cytoskeleton via inducing F-actin.

CONCLUSIONS

In conclusion, our results first provided the pivotal role of EphrinB2 in HASMC proliferation initiated by mediating F-actin and demonstrated a prognostic biomarker and the potential targets for therapy to prevent thoracic aortic dissection.

Morphological parameters affecting false lumen thrombosis following type B aortic dissection: a systematic study based on simulations of idealized models

Type B aortic dissection (TBAD) carries a high risk of complications, particularly with a partially thrombosed or patent false lumen (FL). Therefore, uncovering the risk factors leading to FL thrombosis is crucial to identify high-risk patients. Although studies have shown that morphological parameters of the dissected aorta are related to FL thrombosis, often conflicting results have been reported. We show that recent models of thrombus evolution in combination with sensitivity analysis methods can provide valuable insights into how combinations of morphological parameters affect the prospect of FL thrombosis. Based on clinical data, an idealized geometry of a TBAD is generated and parameterized. After implementing the thrombus model in computational fluid dynamics simulations, a global sensitivity analysis for selected morphological parameters is performed. We then introduce dimensionless morphological parameters to scale the results to individual patients. The sensitivity analysis demonstrates that the most sensitive parameters influencing FL thrombosis are the FL diameter and the size and location of intimal tears. A higher risk of partial thrombosis is observed when the FL diameter is larger than the true lumen diameter. Reducing the ratio of the distal to proximal tear size increases the risk of FL patency. In summary, these parameters play a dominant role in classifying morphologies into patent, partially thrombosed, and fully thrombosed FL. In this study, we point out the predictive role of morphological parameters for FL thrombosis in TBAD and show that the results are in good agreement with available clinical studies.

Develop ment and validation of a prognostic dynamic nomogram for in-hospital mortality in patients with Stanford type B aortic dissection

Background

This study aimed to identify the risk factors for in-hospital mortality in patients with Stanford type B aortic dissection (TBAD) and develop and validate a prognostic dynamic nomogram for in-hospital mortality in these patients.

Methods

This retrospective study involved patients with TBAD treated from April 2002 to December 2020 at the General Hospital of Northern Theater Command. The patients with TBAD were divided into survival and non-survival groups. The data were analyzed by univariate and multivariate logistic regression analyses. To identify independent risk factors for in-hospital mortality, multivariate logistic regression analysis, least absolute shrinkage, and selection operator regression were used. A prediction model was constructed using a nomogram based on these factors and validated using the original data set. To assess its discriminative ability, the area under the receiver operating characteristic curve (AUC) was calculated, and the calibration ability was tested using a calibration curve and the Hosmer-Lemeshow test. Clinical utility was evaluated using decision curve analysis (DCA) and clinical impact curves (CIC).

Results

Of the 978 included patients, 52 (5.3%) died in hospital. The following variables helped predict in-hospital mortality: pleural effusion, systolic blood pressure ≥160 mmHg, heart rate >100 bpm, anemia, ischemic cerebrovascular disease, abnormal cTnT level, and estimated glomerular filtration rate <60 ml/min. The prediction model demonstrated good discrimination [AUC = 0.894; 95% confidence interval (CI), 0.850-0.938]. The predicted probabilities of in-hospital death corresponded well to the actual prevalence rate [calibration curve: via 1,000 bootstrap resamples, a bootstrap-corrected Harrell's concordance index of 0.905 (95% CI, 0.865-0.945), and the Hosmer-Lemeshow test (χ² = 8.3334, P = 0.4016)]. DCA indicated that when the risk threshold was set between 0.04 and 0.88, the predictive model could achieve larger clinical net benefits than "no intervention" or "intervention for all" options. Moreover, CIC showed good predictive ability and clinical utility for the model.

Conclusion

We developed and validated prediction nomograms, including a simple bed nomogram and online dynamic nomogram, that could be used to identify patients with TBAD at higher risk of in-hospital mortality, thereby better enabling clinicians to provide individualized patient management and timely and effective interventions.

Predictive value of age, creatinine, and ejection fraction (ACEF) scoring system for operative mortality in patients with Stanford type A aortic dissection

Purpose

Stanford type A aortic dissection (TAAD) is the most common and fatal type of dissection. An easier-to-use risk stratification may help eliminate bias in patients at high risk of dissection. The age, serum creatinine, and ejection fraction (ACEF) score is a simple risk model developed to predict the mortality risk of elective coronary artery bypass graft surgery. This study aimed to evaluate the relationship between preoperative ACEF score and operative mortality in patients with TAAD undergoing emergency surgery.

Methods

In this retrospective cohort study, 113 patients diagnosed with TAAD between January 2017 and September 2021 were evaluated. The primary endpoint was operative mortality. Receiver operating characteristic analysis was performed for the ACEF score, ACEF II score, and European System for Cardiac Operative Risk Evaluation II. Univariate and multivariate analyses of operative mortality were performed using the logistic regression model.

Results

Operative mortality occurred in 23 (20.4%) patients. The cutoff ACEF score was calculated as 1.1 for predicting operative mortality (area under the curve = 0.712, P value = 0.002, sensitivity = 74.0%, specificity = 67.8%, likelihood ratio = 2.3). Based on the cutoff value, 46 (40.7%) patients had a high ACEF score (ACEF ≥ 1.1) and 67 (59.3%) patients had a low ACEF score (ACEF < 1.1). The high ACEF score was associated with an increased incidence of operative mortality compared with the low ACEF score (37.0% vs. 9.0%; P = 0.001).

Conclusions

The ACEF score can be used as a useful and relatively simple tool for risk stratification before TAAD surgery. However, the ACEF score is only indicated for risk assessment and should not affect treatment.

Augmentation Index in Patients with Thoracic Aortic Aneurysm: A Matched Case-Control Study

Thoracic aortic aneurysms (TAA) may be associated with complications such as rupture and dissection, which can lead to a fatal outcome. Increased central arterial stiffness has been proposed to be present in patients with TAA compared to unmatched controls. We aimed to assess whether wall properties in patients with TAA are also altered when compared to a matched control group. Applanation tonometry was performed in 74 adults with TAA and 74 sex, age, weight, height, and left ventricular ejection fraction matched controls. Subsequently analysis of the pulse wave was done using the SphygmoCor System. For comparing the two groups, AIx was adjusted to a heart rate of 75/min (AIx@75). 148 1-to-1 matched participants were included in the final model. There was no significant difference in the Alx@75 between the TAA group and the matched control group [mean (SD) of 24.7 (11.2) % and 22.8 (11.2) %, p = 0.240]. Adjusted for known cardiovascular risk factors, there was no association between TAA and AIx@75. Patients with TAA showed comparable arterial wall properties to cardiovascular risk factor matched controls. Since higher arterial stiffness is associated with TAA progression, it remains to be investigated if increased central arterial stiffness is a relevant factor of TAA emergence.

Clinical Characteristics, Incidences, and Mortality Rates for Type A and B Aortic Dissections: A Nationwide Danish Population-Based Cohort Study From 1996 to 2016

BACKGROUND

Population-based epidemiologic studies of aortic dissections (ADs) are needed. This study aimed to report clinical characteristics, incidences, and mortality rates for adult patients admitted to Danish hospitals with type A AD (TAAD) or type B AD (TBAD) from 1996 through 2016.

METHODS

We conducted a nationwide, population-based register study. All cases of AD registered with International Classification of Diseases, Tenth Revision codes in the Danish National Patient Registry at time of admission to a hospital with available medical records underwent validation. Data were merged between nationwide health registries including the cause of death registry. Patients with validated AD were matched 1:10 on sex and age with patients with hypertension from the general Danish population.

RESULTS

Of 5018 registered cases of AD, 4183 cases underwent review and 3023 (60.2%) were validated as AD. After exclusions, the distribution of validated TAAD and TBAD was 1620 (60.5%) and 1059 (39.5%; P<0.001), 67.5% and 67.0% of patients were men, and mean ages at dissection were 63.5±12.9 and 67.5±12.2 years (P<0.001), respectively. The most prevalent comorbidities for TAAD were hypertension (55.2%), thoracic aortic aneurysms (14.6%), and chronic obstructive pulmonary disease (13.1%); for TBAD, the most prevalent comorbidities were hypertension (64.1%), aortic aneurysms at any location (7.5% to 12.0%), and chronic obstructive pulmonary disease (15.7%). The overall mean annual incidence rate was 4.2/100 000 patient-years. Incidence was significantly higher for TAAD (2.2/100 000) compared with TBAD (1.5/100 000; P<0.001). The 30-day mortality rates for validated TAAD and TBAD were 22.0% and 13.9% (P<0.001), respectively, with no significant changes over time or between sexes. Adjusted 5-year overall mortality rates for TAAD and TBAD were hazard ratio 3.2 (2.9 to 3.5; P<0.001; aortic-related cause of death, 57.0%) and hazard ratio 2.1 (1.9 to 2.4; P<0.001; aortic-related cause of death, 42.8%), respectively, compared with the general hypertensive population. Among patients who survived 30 days from dissection, the adjusted 5-year overall mortality rates were hazard ratio 1.1 (1.0 to 1.3; P=0.12; aortic-related cause of death, 23.2%) and hazard ratio 1.4 (1.2 to 1.6; P<0.001; aortic-related cause of death, 25.6%) for TAAD and TBAD, respectively.

CONCLUSIONS

Hypertension, aortic aneurysms, and chronic obstructive pulmonary disease were the most prevalent comorbidities. The 30-day mortality frequencies were consistent over time with no significant differences between sexes. The 5-year mortality rate was higher for TAAD than TBAD. If the patient survived 30 days from dissection, the mortality rate for patients with TAAD was comparable with that of the general hypertensive population, but the mortality rate was significantly higher in patients with TBAD.

Aortic Dissection

Acute aortic dissection is a highly morbid condition with high mortality that requires emergent surgical evaluation and repair. The intraoperative management of acute aortic dissection requires the anesthesiologist to do far more than administer anesthesia and begins before the patient arrives at the operative theater. High-fidelity communication with the surgeon, knowledge of the surgical plan, knowledge of the anatomy of the dissection, and a nuanced understanding of aortic dissection pathophysiology are all critical aspects of anesthetic management.

Unusual combination of acute aortic dissection, Mayer-Rokitansky-Küster-Hauser syndrome, and 46,XX gonadal dysgenesis: A case report

BACKGROUND

Acute Stanford type A aortic dissection (ATAAD) is a life-threatening disease. Elderly patients are the high-risk population for aortic dissection (AD). Young patients with AD usually have heritable connective tissue diseases such as Marfan syndrome and Loeys-Dietz syndrome. However, young AD patients without heritable connective tissue disease are relatively rare.

CASE PRESENTATION

Herein, we report a case of a 25-year-old female diagnosed with ATAAD accompanied by undeveloped secondary sexual characteristics. Computed tomography angiography (CTA) showed that her AD involved the ascending and abdominal aorta. She had undergone thoracic endovascular aortic stent graft implantation in a local hospital due to acute Stanford type B aortic dissection at age 19. No uterus or ovaries were found on CTA and transabdominal ultrasonography. Sex hormone detection revealed a low estrogen level. G-banded karyotyping analyses revealed a normal 46,XX karyotype. Finally, her abnormalities in the reproductive system were diagnosed as MRKH syndrome and 46,XX gonadal dysgenesis. Whole-exome sequencing (WES) in the patient found an SNP variant of ACTA2 c.773G>A and MYH11 c.5081A>G. MYH11 c.5081A>G was also found in her mother and younger brother. Copy number variations sequencing (CNV-seq) found an approximately 109.30 Kb duplication at chromosome 6p22.3 (Chr 6: g.24920238-25029535) with a copy number of 3. We performed emergent total aortic arch replacement with frozen elephant trunk surgery, and the patient recovered well after surgery. However, her abdominal AD was stilling progression during 6 months of follow-up.

CONCLUSION

To our knowledge, we report the world's first case of early-onset recurrent AD combined with MRKH syndrome and 46,XX gonadal dysgenesis.

Long‐Term Risks of Stroke in Patients With Type A Aortic Dissection: A Nationwide Cohort Study

Background

Patients with type A aortic dissection (TAAD) have a high short‐term risk of stroke. However, whether patients with TAAD have an increased long‐term risk of stroke is still undetermined, and our study aims to address this knowledge gap.

Methods and Results

A nationwide retrospective cohort study was conducted using Taiwan's National Health Insurance Research Database. We included patients with TAAD as well as age‐ and sex‐matched aortic disease–free individuals between 2003 and 2016. Inverse probability of treatment weighting was performed to balance patient characteristics between the groups. The primary outcome was the development of stroke, regardless of subtype; the secondary outcomes were the risk of developing either ischemic or hemorrhagic stroke. The hazard ratios (HRs) of stroke were estimated using the Cox proportional hazards model. After inverse probability of treatment weighting, 3556 and 7023 patients were categorized into the TAAD and aortic disease–free cohorts, respectively. The mean follow‐up period was 5.71 years. The HRs for overall, ischemic, and hemorrhagic strokes in the TAAD cohort were 3.01 (95% CI, 2.40–3.78), 3.18 (95% CI, 2.47–4.10), and 2.32 (95% CI, 1.58–3.41), respectively, compared with the aortic disease–free cohort. Consistent trends of higher stroke risk in patients with TAAD were revealed in the analyses stratified by age; sex; antiplatelet use; and history of hypertension, diabetes, or dyslipidemia.

Conclusions

Our study findings revealed that patients with TAAD had an increased long‐term risk of both ischemic and hemorrhagic strokes. Further studies are warranted to establish optimal strategies for stroke prevention in these patients.

The evolution of arch surgery: Frozen elephant trunk or conventional elephant trunk?

Treatment of aortic arch aneurysms and dissections require highly complex surgical procedures with devastating complications and mortality rates. Currently, repair of the complete arch until the proximal descending thoracic aorta consists of a two-stage procedure, called elephant trunk (ET) technique, or a single stage a single-stage technique referred to as frozen elephant trunk (FET). There is conflicting evidence about the perioperative results of ET in comparison with FET. We carried out a meta-analysis to investigate possible differences in perioperative and early (up to 30 days) outcomes of ET vs. FET, particularly for mortality, spinal cord injury (SCI), stroke, and renal failure. We also performed a meta-regression to explore the effects of age and sex as possible cofactors. Twenty-one studies containing data from interventions conducted between 1997 and 2019 and published between 2008 and 2021 with 3153 patients (68.5% male) were included. ET was applied to 1,693 patients (53.7%) and FET to 1460 (46.3%). Overall mortality after ET was 250/1693 (14.8%) and after FET 116/1460 (7.9%). Relative risk (RR) and 95% confidence interval (CI) were 1.37 [1.04 to 1.81], p = 0.027. There was no significant effect of age and sex. SCI occurrence after the second stage of ET was 45/1693 (2.7%) and after FET 70/1,460 patients (4.8%) RR 0.53 [0.35 to 0.81], p = 0.004. Age and sex were not associated with the risk of SCI. No significant differences were observed between ET and FET in the incidence of stroke and renal failure. Our results indicate that ET is associated with higher early mortality but lower incidence of SCI compared to FET. When studies published in the last 5 years were analyzed, no significant differences in mortality or SCI were found between ET and FET. This difference is attributed to a decrease in mortality after ET, as the mortality after FET did not change significantly over time.

Use of Point-of-Care Ultrasound for Early Identification of Acute Aortic Root Dissection

Point-of-care ultrasound (POCUS) is becoming a frequently utilized imaging tool in the emergency department (ED) as it can aid in early diagnosis of many pathologies. This is a case report of a 55-year-old male who presented to the emergency department by ambulance for sudden onset chest pain followed by a syncopal episode. Point-of-care echocardiogram revealed a large pericardial effusion with a significantly dilated aortic root, concerning for aortic dissection. Patient was emergently taken for a computed tomography (CT) scan, which was only remarkable for an ascending thoracic aortic aneurysm but failed to show an aortic dissection flap. On repeat POCUS, a dissection intimal flap, large pericardial effusion with tamponade physiology, and aortic regurgitation were identified and later confirmed on transesophageal echocardiogram. This case report details a rare pathology that was correctly identified on initial POCUS before it was seen on CT scan.

Methamphetamine induces thoracic aortic aneurysm/dissection through C/EBPβ

AIMS

Thoracic aortic aneurysm/dissection (TAAD) is a life-threatening disease with diverse clinical manifestations. Although the association between methamphetamine (METH) and TAAD is frequently observed, the causal relationship between METH abuse and aortic aneurysm/dissection has not been established. This study was designed to determine if METH causes aortic aneurysm/dissection and delineate the underlying mechanism.

METHODS AND RESULTS

A new TAAD model was developed by exposing METH to SD rats pre-treated with lysyl oxidase inhibitor β-aminopropionitrile (BAPN). Combination of METH and BAPN caused thoracic aortic aneurysm/dissection in 60% of rats. BAPN+METH significantly increased the expression and activities of both matrix metalloproteinase MMP2 and MMP9, consistent with the severe elastin breakage and dissection. Mechanistically, METH increased CCAAT-enhancer binding protein β (C/EBPβ) expression by enhancing mothers against decapentaplegic homolog 3 (Smad3) and extracellular regulated protein kinase (ERK1/2) signaling. METH also promoted C/EBPβ binding to MMP2 and MMP9 promoters. Blocking C/EBPβ significantly attenuated METH+BAPN-induced TAAD and MMP2/MMP9 expression. Moreover, BAPN+METH promoted aortic medial smooth muscle cell (SMC) apoptosis through C/EBPβ-mediated IGFBP5/p53/PUMA signaling pathways. More importantly, the expression of C/EBPβ, MMP2/MMP9, and apoptosis-promoting proteins was increased in the aorta of human patients with thoracic aortic dissection, suggesting that the mechanisms identified in animal study could be relevant to human disease.

CONCLUSIONS

Our study demonstrated that METH exposure has a casual effect on TAAD. C/EBPβ mediates METH-introduced TAAD formation by causing elastin breakage, medial cell loss and degeneration. Therefore, C/EBPβ may be a potential factor for TAAD clinical diagnosis or treatment.

Safety of exercise for adults with thoracic aortic aneurysms and dissections

Background

Current guidelines for patients with thoracic aortic aneurysms or dissections (TAD) restrict vigorous exertion with the intention to prevent acute aortic dissections. However, a safe threshold for exercise intensity has not been established for TAD patients. In this study, we measured exertional changes in systolic and diastolic blood pressure during isometric and dynamic exercises in a cohort of TAD patients to determine safety of moderate intensity exercise.

Methods

Thirty-one adults with TAD and 14 controls were recruited from UTHealth outpatient clinics. All participants completed an exercise protocol consisting of two circuits of five moderate intensity exercises: hand grips, leg raises, bicep curls, stationary cycling, and wall sits. Blood pressure values were recorded during exercise using Spacelabs OnTrak Ambulatory Blood Pressure monitors. Perceived exertion during each exercise was measured using the Borg CR-10 scale.

Results

No significant differences in the maximum exertional systolic pressure, diastolic pressure, or change from baseline was found between the TAD and control groups. Higher amounts of self-reported weekly moderate activity level (MAL) in TAD correlated with lower exertional SBP during exercise. Higher Borg scores were associated with a greater change in systolic pressure.

Conclusion

Moderate intensity exercise is safe and feasible for many TAD patients. Our data confirms that the Borg score may be a useful proxy for exercise intensity. In this study, we establish a reproducible exercise protocol that can be adapted to create individualized exercise regimens for TAD patients as part of a care plan to improve long-term cardiovascular health.

Predictors and Rate of Progression of Aortic Root and Ascending Aorta Dilatation

In the absence of risk factors like bicuspid aortic valve, connective tissue disorder, or family history of aortic dissections, degenerative thoracic aortic aneurysm appears to be an indolent disease. Most American and European societies recommend yearly or biannual imaging of the thoracic aorta with computed tomographic (CT) imaging, magnetic resonance (MRI) imaging, and transthoracic echocardiographic (TTE) examination. We aimed to identify the rate of progression and predictors of early degenerative aortic root dilatation (ARD) and ascending aortic dilatation (AAD) over a period of 10 years on the basis of echocardiographic measurements. A retrospective chart analysis was performed on 340 patients (mean age 67.4 ± 11.6 years; 85.6% men; 83.8% White) with known ARD and AAD. Aortic root and ascending aorta measurements were followed by serial echocardiograms from the time of the first diagnosis for a total of 10 years. During this time, the mean change in ARD was 0.28 ± 0.71 mm and AAD was 0.15 ± 0.18 mm. On multivariate regression after adjusting for baseline demographics, risk factors, and medication use, there was no statistically significant increase in their unit change in mean ARD or AAD. In conclusion, mild to moderate degenerative thoracic aortic aneurysm has a minimal change in dimensions over time, and current guidelines recommending yearly surveillance imaging of ARD and AAD need to be revisited to allow a more liberal follow-up interval.

Iatrogenic Type A Aortic Dissection: Challenges and Frontiers-Contemporary Single Center Data and Clinical Perspective

Iatrogenic aortic dissection (IAD) is a rare but devastating complication in cardiac surgery and related procedures. Due to its rarity, published data on emergency surgery following IAD are limited. Herein, we discuss IAD occurring intra- and postoperatively, including those occurring during transcatheter aortic valve replacement and cardiac catheterization, and present benchmark data from our consecutive, single-center experience. We demonstrate changes in patient characteristics, surgical approaches, and outcomes over a 23-year period.

Atypical Presentation of Aortic Dissection in a Young Female and the Utility of Point-of-Care Ultrasound in Identifying Aortic Dissection in the Emergency Department

In the absence of prompt diagnosis and treatment, aortic dissection is an extremely dangerous and often fatal medical condition, of which acute coronary syndrome, stroke, limb ischemia, pulmonary embolism, and acute mesenteric ischemia are all possible manifestations. Neurological manifestations of aortic dissection are often missed at presentation. We report a case of a 23-year-old female without any prior characteristics of connective tissue disorder presenting to the emergency department with headache and right upper limb weakness and the utility of bedside point-of-care ultrasound (POCUS) for diagnosing aortic dissection.

Fibrillin-1 Gene Polymorphisms (rs145233125, rs11070646, rs201170905) Are Associated With the Susceptibility and Clinical Prognosis of DeBakey Type III Aortic Dissection in Chinese Han Population

ABSTRACT

We aim to investigate whether genetic variants of the Fibrillin-1 (FBN1) gene were associated with DeBakey type III aortic dissection (AD) and its clinical prognosis in Chinese Han population. Three single-nucleotide polymorphisms (SNPs) (rs145233125, rs11070646, rs201170905) in FBN1 were analyzed in patients with DeBakey type III AD (159) and healthy subjects (216). Gene-environment interactions were evaluated to use generalized multifactor dimensionality reduction. Haplotype analysis of the 3 SNPs in the FBN1 gene was performed by Haploview software. Patients were followed up for average 4 years. G carriers of rs11070646 and rs201170905 in FBN1 have an increased risk of DeBakey type III AD. The interaction of FBN1 and environmental factors facilitated to the increased risk of DeBakey type III AD (cross-validation consistency = 10/10, P = 0.001). One of the most common haplotypes revealed an increased risk of DeBakey type III AD (CGG, P = 0.009). Recessive models of rs145233125 CC genotype ( P < 0.05) and rs201170905 GG genotype ( P < 0.001) were associated with an increased risk of death and recurrent chest pain of DeBakey type III AD. In conclusions, FBN1 gene polymorphisms contribute to DeBakey type III AD susceptibility. The interactions of gene and environment are related with the risk of DeBakey type III AD. C carriers of rs145233125 and G carriers of rs201170905 may be the adverse prognostic indicators of death and recurrent chest pain in DeBakey type III AD.

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.

Serum Oxylipin Profiles Identify Potential Biomarkers in Patients with Acute Aortic Dissection

Aortic dissection (AD) is a life-threatening cardiovascular disease with a dismal prognosis. Inflammation plays an important role in AD. Oxylipins are bioactive lipids involved in the modulation of inflammation and may be involved in the pathogenesis and progression of AD. This study aims to identify possible metabolites related to AD. A total of 10 type A Aortic dissection (TAAD) patients, 10 type B Aortic dissection (TBAD) patients and 10 healthy controls were included in this study. Over 100 oxylipin species were identified and quantified by liquid chromatography with tandem mass spectrometry (LC-MS/MS) analysis. Our investigation demonstrated substantial alterations in 91 oxylipins between AD and healthy individuals. Patients with TAAD had 89 entries accessible compared to healthy controls. According to orthogonal partial least squares discriminant analysis (OPLS-DA), fitness (R²X = 0.362 and R²Y = 0.807, p = 0.03) and predictability (Q² = 0.517, p = 0.005) are the validation parameters between the two groups. Using multivariate logistic regression, 13-HOTrE and 16(17)-EpDPE were the risk factors in the aortic patients group compared to healthy people (OR = 2.467, 95%CI:1.256–7.245, p = 0.035; OR = 0.015, 95%CI:0.0002–0.3240, p = 0.016, respectively). In KEGG enrichment of differential metabolites, the arachidonic acid metabolism pathway has the most metabolites involved. We established a diagnostic model in distinguishing between AD and healthy people. The AUC was 0.905. Oxylipins were significantly altered in AD patients, suggesting oxylipin profile is expected to exploit a novel, non-invasive, objective diagnosis for AD.

Regional delamination strength in the human aorta underlies the anatomical localization of the dissection channel

Aortic dissection is a life-threatening event, during which a primary tear propagates along the aorta causing catastrophic delamination of the inner (intima with most of the media) from the outer layers (leftover media with adventitia). Our understanding of mode-I fracture resistance at different aortic regions is incomplete, although the anatomical localization of the dissection channel may be assigned to this factor. To determine whether the susceptibility to dissection propagation varied with aortic region, the average and standard deviation of peel tension (indices of adhesive strength between layers when pulled apart and its fluctuation) were measured in 24 cadaveric subjects. Measurements were made in the inner and outer quadrants of 9 consecutive regions. Strong regional heterogeneity was established that was age-related based on the following evidence: (1) the average and standard deviation of peel tension peaked in the ascending aorta, decreasing to almost constant values in the descending thoracic aorta, but increasing across the abdominal aorta; (2) axial differences were more pronounced in the inner quadrant, with differences among quadrants reaching significance proximally; (3) the average peel tension was greatly impaired from <40 to 40-60 but much less to >60-year-old subjects at most regions/quadrants, leading to non-uniform axial variations in all age groups; (4) gender affected little the data. This comprehensive series of delamination tests explains the clinical observation of most dissections initiating in the ascending aorta to extend distally and of few dissections initiating in the descending thoracic aorta to extend proximally, while supporting the increased vulnerability in aged subjects.

High heritability of ascending aortic diameter and trans-ancestry prediction of thoracic aortic disease

Enlargement of the aorta is an important risk factor for aortic aneurysm and dissection, a leading cause of morbidity in the developed world. Here we performed automated extraction of ascending aortic diameter from cardiac magnetic resonance images of 36,021 individuals from the UK Biobank, followed by genome-wide association. We identified lead variants across 41 loci, including genes related to cardiovascular development (HAND2, TBX20) and Mendelian forms of thoracic aortic disease (ELN, FBN1). A polygenic score significantly predicted prevalent risk of thoracic aortic aneurysm and the need for surgical intervention for patients with thoracic aneurysm across multiple ancestries within the UK Biobank, FinnGen, the Penn Medicine Biobank and the Million Veterans Program (MVP). Additionally, we highlight the primary causal role of blood pressure in reducing aortic dilation using Mendelian randomization. Overall, our findings provide a roadmap for using genetic determinants of human anatomy to understand cardiovascular development while improving prediction of diseases of the thoracic aorta.

Toward standard abbreviations and acronyms for use in articles on aortic disease

Objectives

Academic medical literature is fraught with complex article-specific acronyms and abbreviations that can impair communication and make reading arduous. Our goal is to ease frustration with bespoke, inconsistent, and variable sets of abbreviations that currently exist for common aorta-related terminology (eg, anatomy, imaging, disease, and therapy). We hope to ease reading and improve communication in the aortic sphere of cardiovascular literature.

Methods

We reviewed a total of 205 published references related to aortic disease, including a systematic review of aorta-related articles in the Journal of Thoracic and Cardiovascular Surgery from the years 2020 and 2021. The array of variable definitions, abbreviations, and acronyms encountered in different papers that refer to the same terminology was striking, revealing that there were few standardized abbreviations in the aortic literature. We cataloged these terms, their associated abbreviations, and their frequency of use, and compiled a list of proposed standard abbreviations for commonly used terms that could be implemented uniformly in articles written about aortic diseases.

Results

We present suggested acronyms and abbreviations for common terminology related to the aorta. It is anticipated that this standard list will evolve over time as the literature and technology of the field grows and develops.

Conclusions

A proposed standard set of acronyms and abbreviations for aorta-related terminology is provided that, if found useful, could be implemented broadly in the aortic literature.

Cardiovascular Outcomes in Aortopathy: GenTAC Registry of Genetically Triggered Aortic Aneurysms and Related Conditions

BACKGROUND

The GenTAC (Genetically Triggered Thoracic Aortic Aneurysm and Cardiovascular Conditions) Registry enrolled patients with genetic aortopathies between 2007 and 2016.

OBJECTIVES

The purpose of this study was to compare age distribution and probability of elective surgery for proximal aortic aneurysm, any dissection surgery, and cardiovascular mortality among aortopathy etiologies.

METHODS

The GenTAC study had a retrospective/prospective design. Participants with bicuspid aortic valve (BAV) with aneurysm (n = 879), Marfan syndrome (MFS) (n = 861), nonsyndromic heritable thoracic aortic disease (nsHTAD) (n = 378), Turner syndrome (TS) (n = 298), vascular Ehlers-Danlos syndrome (vEDS) (n = 149), and Loeys-Dietz syndrome (LDS) (n = 121) were analyzed.

RESULTS

The 25% probability of elective proximal aortic aneurysm surgery was 30 years for LDS (95% CI: 18-37 years), followed by MFS (34 years; 95% CI: 32-36 years), nsHTAD (52 years; 95% CI: 48-56 years), and BAV (55 years; 95% CI: 53-58 years). Any dissection surgery 25% probability was highest in LDS (38 years; 95% CI: 33-53 years) followed by MFS (51 years; 95% CI: 46-57 years) and nsHTAD (54 years; 95% CI: 51-61 years). BAV experienced the largest relative frequency of elective surgery to any dissection surgery (254/33 = 7.7), compared with MFS (273/112 = 2.4), LDS (35/16 = 2.2), or nsHTAD (82/76 = 1.1). With MFS as the reference population, risk of any dissection surgery or cardiovascular mortality was lowest in BAV patients (HR: 0.13; 95% CI: 0.08-0.18; HR: 0.13; 95%: CI: 0.06-0.27, respectively). The greatest risk of mortality was seen in patients with vEDS.

CONCLUSIONS

Marfan and LDS cohorts demonstrate age and event profiles congruent with the current understanding of syndromic aortopathies. BAV events weigh toward elective replacement with relatively few dissection surgeries. Nonsyndromic HTAD patients experience near equal probability of dissection vs prophylactic surgery, possibly because of failure of early diagnosis.

Unilateral versus bilateral anterograde cerebral perfusion in acute type A aortic dissection repair: A systematic review and meta-analysis

OBJECTIVES

The aim of the study is to compare the safety and efficacy of unilateral anterograde cerebral perfusion (UACP) and bilateral anterograde cerebral perfusion (BACP) for acute type A aortic dissection (ATAAD).

METHODS

A systematic review of the MEDLINE (PubMed), Scopus, and Cochrane Library databases (last search: August 7th, 2021) was performed according to the PRISMA statement. Studies directly comparing UACP versus BACP for ATAAD were included. Random-effects meta-analyses were performed.

RESULTS

Eight retrospective cohort studies were identified, incorporating 2416 patients (UACP: 843, BACP: 1573). No statistically significant difference was observed regarding in-hospital mortality (odds ratio [OR]:1.05 [95% Confidence Interval (95% CI):0.70-1.57]), permanent neurological deficit (PND) (OR: 0.94 [95% CI: 0.52-1.70]), transient neurological deficit (TND) (OR: 1.37 [95% CI: 0.98-1.92]), renal failure (OR: 0.96 [95% CI: 0.70-1.32]), and re-exploration for bleeding (OR: 0.77 [95% CI: 0.48-1.22]). Meta-regression analysis revealed that PND and TND were not influenced by differences in rates of total arch repair, Bentall procedure, and concomitant CABG in UACP and BACP groups. Cardiopulmonary bypass time (Standard Mean Difference [SMD]: -0.11 [95% CI: -0.22, 0.44]), Cross clamp time (SMD: -0.04 [95% CI: -0.38, 0.29]), and hypothermic circulatory arrest time (SMD: -0.12 [95% CI: -0.55, 0.30]) were comparable between UACP and BACP. Intensive care unit stay was shorter in BACP arm (SMD:0.16 [95% CI: 0.01, 0.31]); however, length of hospital stay was shorter in UACP arm (SMD: -0.25 [95% CI: -0.45, -0.06]).

CONCLUSIONS

UACP and BACP had similar results in terms of in-hospital mortality, PND, TND, renal failure, and re-exploration for bleeding rate in patients with ATAAD. ICU stay was shorter in the BACP arm while LOS was shorter in the UACP arm.

Genome-Wide Identification of Associations of Circulating Molecules With Spontaneous Coronary Artery Dissection and Aortic Aneurysm and Dissection

Circulating proteins play functional roles in various biological processes and disease pathogenesis. The aim of this study was to highlight circulating proteins associated with aortic aneurysm and dissection (AAD) and spontaneous coronary artery dissection (SCAD). We examined the associations of circulating molecule levels with SCAD by integrating data from a genome-wide association study (GWAS) of CanSCAD and 7 pQTL studies. Mendelian randomization (MR) analysis was applied to examine the associations between circulating molecule levels and AAD by using data from UK Biobank GWAS and pQTL studies. The SCAD-associated SNPs in 1q21.2 were strongly associated with circulating levels of extracellular matrix protein 1 (ECM1) and 25 other proteins (encoded by CTSS, CAT, CNDP1, KNG1, SLAMF7, TIE1, CXCL1, MBL2, ESD, CXCL16, CCL14, KCNE5, CST7, PSME1, GPC3, MAP2K4, SPOCK3, LRPPRC, CLEC4M, NOG, C1QTNF9, CX3CL1, SCP2D1, SERPINF2, and FN1). These proteins were enriched in biological processes such as regulation of peptidase activity and regulation of cellular protein metabolic processes. Proteins (FGF6, FGF9, HGF, BCL2L1, and VEGFA) involved in the Ras signaling pathway were identified to be related to AAD. In addition, SCAD- and AAD-associated SNPs were associated with cytokine and lipid levels. MR analysis showed that circulating ECM1, SPOCK3 and IL1b levels were associated with AAD. Circulating levels of low-density lipoprotein cholesterol and small very-low-density lipoprotein particles were strongly associated with AAD. The present study found associations between circulating proteins and lipids and SCAD and AAD. Circulating ECM1 and low-density lipoprotein cholesterol may play a role in the pathology of SCAD and AAD.

Aortic dissection in Indonesia male: 3 case report

Background

Aortic dissection (AD) is a life-threatening rare condition caused by a tear in the aortic wall which requires urgent surgery.

Case presentation

3 Indonesian males obtained a CT angiography (CTA) showing a picture of AD which was confirmed using the Stanford and De Bakey classification. The patient was successful in undergoing TEVAR and open-heart surgery which 2 patients survived and 1 patient died.

Discussion

The speed of handling in AD is the key to successful management of AD supported by an understanding of the signs and symptoms and results of thoracoabdominal CTA.

Conclusion

The ability to interpret CTA results and understand AD sign symptoms is very helpful in minimizing mortality.