Pathology of the thoracic aorta: a morphologic review of 338 surgical specimens over a 7-year period

Outcomes of post-implantation syndrome after endovascular repair for Stanford type B aortic dissection

OBJECTIVE

The aim of this study was to investigate the correlation between post-implantation syndrome (PIS) and long-term prognosis in patients with Stanford type B aortic dissection (TBAD) undergoing thoracic endovascular aortic repair (TEVAR).

METHODS

This retrospective study included 547 consecutive patients diagnosed with TBAD who underwent TEVAR at our institution between January 2014 and December 2019. Patients were categorized into two groups: the PIS group (patients with post-TEVAR PIS) and the non-PIS group (patients without post-TEVAR PIS). In-hospital and follow-up data were analyzed.

RESULTS

The incidence of PIS was 28.9% (158/547 patients). No baseline differences were observed between the PIS (n = 158) and the non-PIS (n = 389) groups. The proportion of emergency surgery in the PIS group was higher than that in the non-PIS group (44.9% vs 26.0%; P < .001), the operation time was longer (median, 65.0; interquartile range [IQR], 56.0-75.0 minutes vs 56.0; IQR, 45.0-66.0 minutes; P < .001), the volume of contrast medium used (median, 65.0; IQR, 56.0-75.0 mL vs 56.0; IQR, 45.0-66.0 mL; P < .001), and the average number of trunk stents (1.85 ± 0.4 vs 1.34 ± 0.5 pieces; P < .001) and branch stents (0.7 ± 0.7 vs 0.2 ± 0.5 pieces; P < .001) used were more in the PIS group than in the non-PIS group. The incidence of supra-aortic branch procedures was higher in the PIS group than in the non-PIS group. There was no significant difference in device-related complications (DRCs) or 30-day mortality between the two groups (2.5% vs 4.4%; P = .442 and 1.3% vs 1.3%; P = .688, respectively). Univariate and multivariable logistic regression analysis showed that emergency surgery, number of trunk stents >1, operation time >58.5 minutes, and contrast medium volume >75 mL were risk factors for PIS, and the odds ratios of emergency operation, number of trunk stents >1 piece, operation time >58.5 minutes, and contrast medium volume >75 mL were 2.526 (95% confidence interval [CI], 1.530-4.173), 4.651 (95% CI, 2.838-7.624), 3.577 (95% CI, 2.201-5.815), and 7.356 (95% CI, 4.111-13.160), respectively. Follow-up was completed in 98.5% (532/540) of the patients, with a median follow-up of 67 months (IQR, 50-86 months). There was no significant difference in survival between the PIS and non-PIS groups (12.4% vs 10.3%; P = .476) during follow-up. The incidences of DRCs (7.8% vs 11.6%; P = .200) and aortic false lumen thrombosis (75.8% vs 79.2%; P = .399) were comparable between the PIS and non-PIS groups. Univariate logistic regression analysis showed that PIS had no effect on long-term follow-up mortality, DRCs, entry flow, or aortic false lumen thrombosis rate.

CONCLUSIONS

PIS is relatively common after TEVAR and emergency surgery; number of trunk stents >1, operation time >58.5 minutes, and contrast medium volume >75 mL are of high predictive value for the assessment of PIS after TEVAR. However, PIS had little effect on early and late postoperative mortality or DRCs.

Longitudinal Assessment of Inflammatory Activity in Acute Type B Aortic Dissection with Integrated Fluorodeoxyglucose Positron Emission Tomography/Magnetic Resonance Imaging

OBJECTIVE

The significance of the inflammatory response in the natural course of acute type B aortic dissection (ATBAD) is unknown. The aim was to characterise inflammation and its transformation over time in ATBAD using 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) with contrast enhanced magnetic resonance imaging (MRI).

METHODS

Ten patients underwent FDG-PET/MRI within two weeks of ATBAD (acute phase), three to four months (subacute phase), nine to 12 months (early chronic phase), and 21 to 24 months (late chronic phase) after ATBAD. Target background ratios (TBRs) were measured in the ascending aorta, aortic arch, and descending aorta. MRI inflammatory markers were assessed in the descending aorta.

RESULTS

Ten patients were included: median age 69 years, median clinical follow up 32 months. In the acute phase there was increased FDG uptake in the descending aorta (maximum TBR 5.8, SD [standard deviation] 1.3) compared with the ascending aorta (TBR 3.3, SD 0.8, p < .010) and arch (TBR 4.2, SD 0.6, p = .010). The maximum TBR of the descending aorta decreased from the acute to subacute phase (TBR 3.5, SD 0.6, p = .010) and further to the early chronic phase (TBR 2.9, SD 0.4, p = .030) but was stable thereafter. The acute phase maximum TBR in the ascending aorta (TBR 3.3) and arch (TBR 4.2) decreased to the subacute phase (ascending: TBR 2.8, SD 0.6, p = .020; arch: TBR 2.7, SD 0.4, p = .010) and was stable thereafter. Four patients underwent surgical aortic repair (three for aortic dilatation at one, five, and 28 months and one for visceral ischaemia at three weeks). MRI signs of inflammation were present in all surgically treated patients vs. two of six of medically treated patients (p= .048).

CONCLUSION

ATBAD is associated with increased FDG uptake in the acute phase primarily in the descending aorta, but also involving the aortic arch and ascending aorta, indicating an inflammatory response in the whole aorta. Inflammation subsides early in the ascending aorta and arch (three months), whereas it stabilised later in the descending aorta (nine to 12 months). MRI signs of inflammation were more frequent in patients who later needed surgical treatment and merit further investigation.

Smooth Muscle Heterogeneity and Plasticity in Health and Aortic Aneurysmal Disease

Vascular smooth muscle cells (VSMCs) are the predominant cell type in the medial layer of the aorta, which plays a critical role in the maintenance of aortic wall integrity. VSMCs have been suggested to have contractile and synthetic phenotypes and undergo phenotypic switching to contribute to the deteriorating aortic wall structure. Recently, the unprecedented heterogeneity and diversity of VSMCs and their complex relationship to aortic aneurysms (AAs) have been revealed by high-resolution research methods, such as lineage tracing and single-cell RNA sequencing. The aortic wall consists of VSMCs from different embryonic origins that respond unevenly to genetic defects that directly or indirectly regulate VSMC contractile phenotype. This difference predisposes to hereditary AAs in the aortic root and ascending aorta. Several VSMC phenotypes with different functions, for example, secreting VSMCs, proliferative VSMCs, mesenchymal stem cell-like VSMCs, immune-related VSMCs, proinflammatory VSMCs, senescent VSMCs, and stressed VSMCs are identified in non-hereditary AAs. The transformation of VSMCs into different phenotypes is an adaptive response to deleterious stimuli but can also trigger pathological remodeling that exacerbates the pathogenesis and development of AAs. This review is intended to contribute to the understanding of VSMC diversity in health and aneurysmal diseases. Papers that give an update on VSMC phenotype diversity in health and aneurysmal disease are summarized and recent insights on the role of VSMCs in AAs are discussed.

Thoracic Aortic Aneurysm and Dissection: Review and Recommendations for Evaluation

ABSTRACT

Aortic dissection and rupture (collectively termed "sudden aortic death") are commonly encountered by forensic pathologists, with an estimated incidence at autopsy between 0.6% and 7.7%. Despite this, there is no standard of practice for the evaluation of sudden aortic death at autopsy.Recent studies have shown 20% of patients with thoracic aortic aneurysm or dissection (TAAD) have an identifiable genetic syndrome, and 19% will have an affected first-degree relative. The past 2 decades have seen identification of new culprit genes and syndromes, which can have subtle or nonexistent external phenotypes. A high index of suspicion is warranted to identify possible hereditary TAAD (H-TAAD), allowing family members to obtain screening to avoid catastrophic vascular events. Forensic pathologists need broad knowledge of the spectrum of H-TAAD and awareness of the relative significance of hypertension, pregnancy, substance use, and microscopic changes of aortic architecture.This article reviews the common subtypes of H-TAAD, including Marfan syndrome, vascular Ehlers-Danlos, Loeys-Dietz, and familial thoracic aortic aneurysm and dissection. Recommendations for the evaluation of sudden aortic death at autopsy are presented, including (1) performance of a complete autopsy, (2) documentation of aortic circumference and valve morphology, (3) notifying family of the need for screening, and (4) preservation of a sample for potential genetic testing.

Histopathological findings of diseased ascending aortae with clinicopathological correlation - A single-centre study of 160 cases

The most common reason for ascending aorta resection is an aneurysm or dissection. Aortic dissection is a life-threatening condition in which an aneurysm is a crucial risk factor. The essential criteria for aneurysm resection include the diameter, genetic predisposition, and aortic valve disease. This study aimed to compare the histological findings in aneurysms and dissections and correlate them with clinical parameters to determine whether histopathological findings correspond with the current clinical approach. A total of 160 ascending aorta surgical specimens, separate or with an aortic valve, were collected and divided into four groups: aneurysm-tricuspid (n = 40; median 67 y), aneurysm-malformed (n = 68; median 50 y), dissection-tricuspid (n = 48; median 65.5 y), and dissection-malformed (n = 4; median 52.5 y). Male preponderance was observed in all groups; the youngest patients were in the aneurysm-malformed group. None of the specimens showed normal aortic histology. The most common finding in the aortic samples was medial degeneration, which was the most severe and most common in dissection. The mildest findings were found in the aneurysm-malformed group. Atherosclerosis was predominant and most severe in the aneurysm-tricuspid group, while only mild in both dissection groups, suggesting its protective effect against this complication. Chronic aortitis was the least common pathology, found only in the aneurysm-tricuspid group. The aortic valve was resected and examined simultaneously with the ascending aorta in 76 cases, most commonly in the aneurysm-malformed group (n = 53). Myxoid degeneration was the major finding in the tricuspid aortic valves, with calcifications in the malformed. Comparing the histopathological results with the clinical aspects, aneurysms with a malformed aortic valve seem to be managed appropriately, with the findings not reaching the severity as in patients with a tricuspid valve. In contrast, in patients with a tricuspid valve, there were more dissections than aneurysms, with a significant subset of aneurysms showing histological findings almost identical to those of dissections. Supported by histological findings, patients with a diseased ascending aorta and tricuspid aortic valve represent an underdiagnosed risk group that would benefit from earlier diagnosis and intervention to prevent dissection. There is a need to find a marker for dissection risk other than the aortic diameter.

Aortic tissue pathology in reoperative post-dissection repair following prior use of BioGlue

AIM

The benefits of BioGlue as a surgical adjunct in aortic procedures have been demonstrated in several studies, but limited information is available regarding the associated histopathological findings of aortic tissue at the time of reoperation. The objective of this study was to assess, at reoperation, the histopathological characteristics of aortic tissue which has had BioGlue applied during a previous surgery.

METHODS

This prospective, single-center, single-arm study enrolled patients who were undergoing aortic reoperation and who had BioGlue used during previous aortic surgery. Histopathological assessment of aortic specimens obtained intraoperatively was performed on tissue that would have been removed independent of subject participation in the study.

RESULTS

A total of 11 patients were enrolled and based on gross assessment, excessive amounts of BioGlue had been applied during the initial surgery in 36.4% of cases. The samples with the greatest amount of residual BioGlue demonstrated moderate to marked inflammatory responses, while the remaining samples demonstrated minimal to moderate inflammatory responses. Calcification of residual BioGlue was noted in 4 cases. Substantial medial degeneration was associated with suture line dehiscence in 4 cases, some of which had a large quantity of residual BioGlue. No evidence of suture degradation was observed.

CONCLUSIONS

Cases with surgical anastomosis dehiscence were associated with substantial medial degeneration. While no histologic findings directly linked BioGlue to these degenerative changes, a contributory role cannot be excluded. Following the manufacturer's instructions for appropriate application of BioGlue is crucial to prevent potential complications.

STIM and Orai Mediated Regulation of Calcium Signaling in Age-Related Diseases

Tight spatiotemporal regulation of intracellular Ca²⁺ plays a critical role in regulating diverse cellular functions including cell survival, metabolism, and transcription. As a result, eukaryotic cells have developed a wide variety of mechanisms for controlling Ca²⁺ influx and efflux across the plasma membrane as well as Ca²⁺ release and uptake from intracellular stores. The STIM and Orai protein families comprising of STIM1, STIM2, Orai1, Orai2, and Orai3, are evolutionarily highly conserved proteins that are core components of all mammalian Ca²⁺ signaling systems. STIM1 and Orai1 are considered key players in the regulation of Store Operated Calcium Entry (SOCE), where release of Ca²⁺ from intracellular stores such as the Endoplasmic/Sarcoplasmic reticulum (ER/SR) triggers Ca²⁺ influx across the plasma membrane. SOCE, which has been widely characterized in non-excitable cells, plays a central role in Ca²⁺-dependent transcriptional regulation. In addition to their role in Ca²⁺ signaling, STIM1 and Orai1 have been shown to contribute to the regulation of metabolism and mitochondrial function. STIM and Orai proteins are also subject to redox modifications, which influence their activities. Considering their ubiquitous expression, there has been increasing interest in the roles of STIM and Orai proteins in excitable cells such as neurons and myocytes. While controversy remains as to the importance of SOCE in excitable cells, STIM1 and Orai1 are essential for cellular homeostasis and their disruption is linked to various diseases associated with aging such as cardiovascular disease and neurodegeneration. The recent identification of splice variants for most STIM and Orai isoforms while complicating our understanding of their function, may also provide insight into some of the current contradictions on their roles. Therefore, the goal of this review is to describe our current understanding of the molecular regulation of STIM and Orai proteins and their roles in normal physiology and diseases of aging, with a particular focus on heart disease and neurodegeneration.

Histological regional analysis of the aortic root and thoracic ascending aorta: a complete analysis of aneurysms from root to arch

Background

Although aortic root and ascending aortic aneurysms are treated the same, they differ in embryological development and pathological processes. This study examines the microscopic structural differences between aortic root and ascending aortic aneurysms, correlating these features to the macroscopic pathophysiological processes.

Methods

We obtained surgical samples from ascending aortic aneurysms (n = 11), aortic root aneurysms (n = 3), and non-aneurysmal patients (n = 7), Aortic collagen and elastin content were examined via histological analysis, and immunohistochemistry techniques used to determine collagen I, III, and IV subtypes. Analysis was via observational features, and colour deconvolution quantification techniques.

Results

Elastin fiber disruption and fragmentation was the most extensive in the proximal aneurysmal regions. Medial fibrosis and collagen density increased in proximal aneurysmal regions and aortic root aneurysms (p < 0.005). Collagen I was seen in highest quantity in aortic root aneurysms. Collagen I content was greatest in the sinus tissue regions compared to the valvular and ostial regions (p < 0.005) Collagen III and IV quantification did not vary greatly. The most susceptible regions to ultrastructural changes in disease are the proximal ascending aorta and aortic root.

Conclusions

The aortic root differs histologically from the ascending aorta confirming its unique composition in aneurysm pathology. These findings should prompt further evaluation on the influence of this altered structure on function which could potentially guide clinical management.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13019-021-01641-5.

Ascending aorta dissection in a new classification system: Clinicopathological features of 62 cases

Herein we present a single institution 5-year experience with ascending aorta dissection biopsies depicting the clinicopathological features of 62 cases. To detect microscopic abnormalities in the aortic wall beside the dissection itself, we applied a new histopathological classification scheme from the consensus documents issued by The Society for Cardiovascular Pathology and The Association for the European Cardiovascular Pathology in 2015 and 2016. The most common finding was medial degeneration (MD) - 61 cases (98.4%); atherosclerosis (AS) was found in 19 aortae (30.6%), and chronic aortitis- giant cell pattern described in one aorta (1.6%). The medial degeneration constituents included mucoid matrix accumulation, smooth muscle cells and elastic fibers abnormalities, and medial fibrosis. The consensus document application led to increased MD reporting compared to older studies and to our previous experience, probably due to assessing more subtle and focal changes such as intralamellar fibrosis, intralamellar mucoid matrix accumulation, and loss of smooth muscle cell nuclei- these changes being also the most common MD abnormalities we are reporting. We have compared the results in patients with bicuspid (n = 7; 11.3%) versus tricuspid (n = 55; 88.7%) aortic valve, suggesting no significant differences except for translamellar fibrosis, which appeared to be more severe in the bicuspid valve group (p = 0.0397). The results might imply similar histopathological findings regardless of the aortic valve cuspidity in aortic dissection. These findings are in contrast to ascending aorta dilation (aneurysm), where more severe medial degeneration changes have been described in patients with the tricuspid aortic valve.

Comparison of the damage to aorta wall in aortitis versus noninflammatory degenerative aortic diseases

BACKGROUND

Not rarely aortitis is firstly identified in thoracic aorta aneurysm/dissection specimens only by histopathology in the absence of clinical evidence of systemic inflammatory disease emphasizing the importance of histology for the diagnosis of aortitis. Regardless of the improvement of the pathological assessment of aortic diseases by the recent consensus statements on surgical pathology of the aorta, histology can be confusing since medial degenerative changes (MDC) can be prominent in a background where inflammation is sometimes limited. This raises the question of the role of aging or other degenerative process versus the role of inflammation in the damage to aorta wall.

PATIENTS AND METHODS

In this study, besides inflammation, we evaluated aorta samples from aortitis cases focusing on the histological scoring of MDC. In this retrospective single center study, we retrieved 719 cases of ascending aorta aneurysms or dissections operated on from January 2010 until June 2018. MDC (elastic fiber fragmentation and/or loss, smooth muscle nuclei loss, mucoid extracellular matrix accumulation intralemellar or translamellar) were estimated using a scoring system derived from that of the consensus statement. Noninfectious aortitis group versus age-matched non-inflammatory degenerative aortic disease group were compared.

RESULTS

Noninfectious aortitis was pathologically diagnosed in 62 patients (8.6%). Among the 62 noninfectious aortitis patients, 47 patients (75.8%) had aortitis identified pathologically prior to the clinical diagnosis. Higher MDC scores were observed at all aortic sizes in aortitis group versus non-aortitis group, especially for elastic fiber damage and smooth muscle cell loss.

CONCLUSIONS

Aortitis is remarkably associated with severe damage to the aorta wall resulting in advanced MDC scores. Inflammatory process is responsible for higher MDC in the aorta wall than aging or other degenerative process.

Notch signaling in the pathogenesis of thoracic aortic aneurysms: A bridge between embryonic and adult states

Aneurysms of the thoracic aorta are a "silent killer" with no evident clinical signs until the fatal outcome. Molecular and genetic bases of thoracic aortic aneurysms mainly include transforming growth factor beta signaling, smooth muscle contractile units and metabolism genes, and extracellular matrix genes. In recent studies, a role of Notch signaling, among other pathways, has emerged in disease pathogenesis. Notch is a highly conserved signaling pathway that regulates the development and differentiation of many types of tissues and influences major cellular processes such as cell proliferation, differentiation and apoptosis. Mutations in several Notch signaling components have been associated with a number of heart defects, demonstrating an essential role of Notch signaling both in cardiovascular system development and its maintenance during postnatal life. This review discusses the role of Notch signaling in the pathogenesis of thoracic aortic aneurysms considering development and maintenance of the aortic root and how developmental regulations by Notch signaling may influence thoracic aortic aneurysms.

The complex interplay among atherosclerosis, inflammation, and degeneration in ascending thoracic aortic aneurysms

OBJECTIVE

To assess the histopathological findings of a large series of ascending thoracic aortic aneurysm (TAA) surgical specimens applying the updated classification on noninflammatory degenerative and inflammatory aortic diseases proposed by the Association for European Cardiovascular Pathology and the Society for Cardiovascular Pathology clinicopathological correlations.

METHODS

A total of 255 patients surgically treated for ascending TAA were enrolled. Surgical ascending aorta specimens were examined.

RESULTS

The histopathological substrate of ascending TAAs was mainly degenerative (67.5%), but with a remarkable prevalence of atherosclerotic lesions (18.8%) and aortitis (13.7%). Degenerative patients more frequently had bicuspid aortic valve (37.2%; P = .002). Patients in the atherosclerotic group were older (median age, 69 years; P < .001), more often with a history of hypertension (87.5%; P = .059), hypercholesterolemia (75%; P = .019), diabetes (16.6%; P = .054), current smoking (22.9%; P = .066), and a history of coronary artery disease (18.7%; P = .063). Patients with aortitis represented the older group (median age, 75 years, P < .001), were mostly females (68.6%; P < .001), and had a larger ascending aorta diameter (median, 56 mm; P < .001). Both patients with atherosclerosis and aortitis presented a higher incidence of concomitant abdominal aortic aneurysm (20.8% and 22.8%, respectively; P < .001).

CONCLUSIONS

Although degenerative histopathology is the most frequent substrate in ascending TAA, atherosclerosis and inflammation significantly contribute to the development of chronic aortic thoracic disease.

Sub-classification of non-inflammatory and inflammatory surgical aortic aneurysms and the association of histological characteristics with potential risk factors

The present study aimed to analyze the histological characteristics of surgical thoracic aortic aneurysm (TAA) and abdominal aortic aneurysm (AAA) specimens on the basis of the most recent consensus documents on non-inflammatory and inflammatory lesions. The current study also aimed to establish an association with various risk factors. Aortic wall specimens were collected from 52 patients (38 men and 14 women; age, 19–80 years) undergoing surgery for aortic dilatation at The Cardiovascular Disease Institute (Iasi, Romania). For histological evaluation, the aortic specimens (39 TAAs and 13 AAAs) were stained with hematoxylin-eosin, Van Giessen, alcian blue and Movat pentachrome. The specimens were evaluated and graded according to the severity of histopathological conditions: Fragmentation of elastic fibers, medial mucoid accumulation, smooth muscle cell loss and medial fibrosis. The severity of atherosclerotic lesions in surgically resected segments of the aorta were graded as follows: i) mild=1; ii) moderate=2; and iii) severe=3. The risk factors associated with TAA were the male sex (80%), smoking (56%), hypertension (33%) and bicuspid aortic valve (13%). Advanced age (70 years), male sex (69%) and smoking (54%) were determined to be the risk factors of AAA. The histopathological abnormalities included medial degeneration (MD) (82%), atherosclerosis (ATS) (42%) and aortitis (10%). MD was the leading histopathological diagnosis in TAA and the severity of lesions were graded as follows: Mild (8% of cases), moderate (44% of cases) and severe (31% of cases). Severe atherosclerotic lesions were identified in AAA (100% of cases). In the present study, medial degenerative aortic lesions (1, mild; 2, moderate; and 3, severe) significantly correlated with advanced age (>65 years; r=−0.39; P<0.01) and male sex (r=0.27; P<0.05). Significant correlations were also identified between atherosclerotic aortic lesions (1, mild; 2, moderate; and 3, severe) and advanced age (>65 years) (r=−0.40, P<0.01) or smoking (r=−0.29; P<0.05). Advanced age, male sex and smoking were determined to be the main risk factors for the development of degenerative aortic aneurysms.

Assembly of Tissue-Engineered Blood Vessels with Spatially Controlled Heterogeneities

Tissue-engineered human blood vessels may enable in vitro disease modeling and drug screening to accelerate advances in vascular medicine. Existing methods for tissue-engineered blood vessel (TEBV) fabrication create homogenous tubes not conducive to modeling the focal pathologies characteristic of certain vascular diseases. We developed a system for generating self-assembled human smooth muscle cell (SMC) ring units, which were fused together into TEBVs. The goal of this study was to assess the feasibility of modular assembly and fusion of ring building units to fabricate spatially controlled, heterogeneous tissue tubes. We first aimed to enhance fusion and reduce total culture time, and determined that reducing ring preculture duration improved tube fusion. Next, we incorporated electrospun polymer ring units onto tube ends as reinforced extensions, which allowed us to cannulate tubes after only 7 days of fusion, and culture tubes with luminal flow in a custom bioreactor. To create focal heterogeneities, we incorporated gelatin microspheres into select ring units during self-assembly, and fused these rings between ring units without microspheres. Cells within rings maintained their spatial position along tissue tubes after fusion. Because tubes fabricated from primary SMCs did not express contractile proteins, we also fabricated tubes from human mesenchymal stem cells, which expressed smooth muscle alpha actin and SM22-α. This work describes a platform approach for creating modular TEBVs with spatially defined structural heterogeneities, which may ultimately be applied to mimic focal diseases such as intimal hyperplasia or aneurysm.

Curcumin attenuates the development of thoracic aortic aneurysm by inhibiting VEGF expression and inflammation

Angiogenesis is an important process in the pathogenesis of aortic aneurysm. The aim of the present study was to investigate the angiogenic balance and the expression of vascular endothelial growth factor (VEGF) in thoracic aortic aneurysm (TAA). A previous study demonstrated that curcumin exerts a marked effect on aortic aneurysm development. Therefore, the present study determined whether curcumin is able to modulate angiogenesis and inflammatory signaling in TAA by collecting human TAA samples and establishing a rat TAA model using periaortic application of CaCl2. TAA rats were treated with curcumin or 1% carboxymethyl cellulose and were sacrificed 4 weeks after the operation. All tissue specimens were analyzed by histological staining, immunohistochemistry and western blotting. Human TAA samples exhibited increased neovascularization and VEGF expression when compared with normal aortic walls. In rat tissues, treatment with curcumin resulted in reduced aneurysm size and restored the wavy structure of the elastic lamellae. In addition, curcumin decreased neovascularization and the expression of VEGF. Immunohistochemical analysis indicated that curcumin significantly inhibited infiltration of cluster of differentiation (CD)3+ and CD68+ cells in TAA. Furthermore, curcumin treatment decreased the expression of vascular cell adhesion molecule‑1, intracellular adhesion molecule‑1, monocyte chemoattractant protein‑1 and tumor necrosis factor‑α. Collectively, the results demonstrated that angiogenesis and VEGF expression were increased in the aortic wall in TAA. Treatment with curcumin inhibited TAA development in rats, which was associated with suppression of VEGF expression. In addition, curcumin attenuated inflammatory cell infiltration and suppressed inflammatory factor expression in the periaortic tissue of TAA.

Consensus statement on surgical pathology of the aorta from the Society for Cardiovascular Pathology and the Association for European Cardiovascular Pathology: I. Inflammatory diseases

Inflammatory diseases of the aorta include routine atherosclerosis, aortitis, periaortitis, and atherosclerosis with excessive inflammatory responses, such as inflammatory atherosclerotic aneurysms. The nomenclature and histologic features of these disorders are reviewed and discussed. In addition, diagnostic criteria are provided to distinguish between these disorders in surgical pathology specimens. An initial classification scheme is provided for aortitis and periaortitis based on the pattern of the inflammatory infiltrate: granulomatous/giant cell pattern, lymphoplasmacytic pattern, mixed inflammatory pattern, and the suppurative pattern. These inflammatory patterns are discussed in relation to specific systemic diseases including giant cell arteritis, Takayasu arteritis, granulomatosis with polyangiitis (Wegener's), rheumatoid arthritis, sarcoidosis, ankylosing spondylitis, Cogan syndrome, Behçet's disease, relapsing polychondritis, syphilitic aortitis, and bacterial and fungal infections.

Contemporary surgical approaches and outcomes in adults with Kommerell diverticulum

BACKGROUND

Surgery in patients with Kommerell diverticulum (KD) is controversial. Although the presence of symptoms is an accepted indication, the KD itself may be a risk factor for dissection and rupture, although size criteria for operation are undefined.

METHODS

A retrospective review of 19 adult patients who underwent surgical treatment of KD between March 2004 and June 2013 was performed. Mean age was 48 years (range, 32 to 68 years). Fifteen patients were female, 15 were symptomatic, and 13 had a right aortic arch. Sixteen patients with aberrant subclavian artery underwent a two-stage procedure involving subclavian-common carotid artery transposition or bypass followed by aortic resection, including origin of the KD, with interposition graft reconstruction. Aortic resection was performed with left heart bypass (n = 10) or deep hypothermic circulatory arrest (n = 9).

RESULTS

There were no deaths or strokes. Complications after aberrant subclavian artery revascularization were transient ptosis (n = 3), graft occlusion (n = 1), recurrent laryngeal nerve injury (n = 1),phrenic nerve injury (n = 1), and reintubation (n = 1). Complications after aortic resection were intraoperative type A dissection (n = 1), phrenic nerve injury (n = 1), chylothorax (n = 1), and transient neurologic dysfunction (n = 1). Mean hospital stay after aberrant subclavian artery revascularization was 2 ± 2 days and after aortic resection, 6.4 ± 2.4 days. Of 18 available pathology specimens, all 18 showed medial degeneration. Mean follow-up was 3.3 years.

CONCLUSIONS

This is the largest reported single-center experience with the surgical management of KD in adults, verifying its safety and efficacy. The high percentage of KD with medial degeneration suggests asymptomatic patients with an enlarged KD also may benefit from resection.

Dysregulated miR1254 and miR579 for cardiotoxicity in patients treated with bevacizumab in colorectal cancer

Methods for detecting circulating microRNAs (miRNAs), small RNAs that control gene expression, at high sensitivity and specificity in the blood have been reported in recent studies. The goal of this study was to determine if detectable levels of specific miRNAs are released into the circulation for bevacizumab-induced cardiotoxicity. A miRNA array analysis was performed using RNA isolated from 10 control patients in bevacizumab treatment, and n=10 patients have been confirmed to have bevacizumab-induced cardiotoxicity. From the array, we selected 19 candidate miRNA for a second validation study in 90 controls and 88 patients with bevacizumab-induced cardiotoxicity. Consistent with the data obtained from the microRNA array, circulating levels of five miRNAs were significantly increased in patients with bevacizumab-induced cardiotoxicity compared with controls. To confirm these data, we compared selected miRNAs in the plasma of patients with bevacizumab-induced cardiotoxicity with those of 66 patients with acute myocardial infarction (AMI). Moreover, we went on to analyze what factors may influence the levels of potential biomarker miRNAs. Consistent with the data obtained from the microRNA array, circulating levels of five miRNAs were significantly increased in patients with bevacizumab-induced cardiotoxicity compared with those of healthy bevacizumab treatment controls. However, only miRNA1254 and miRNA579 showed high specificity in the validation experiments. Moreover, we went on to analyze what factors may influence the levels of potential biomarker miRNAs. We identify two miRNAs that are specifically elevated in patients with bevacizumab-induced cardiotoxicity, miR1254 and miRNA579, and miRNA1254 shows the strongest correlation to the clinical diagnosis of bevacizumab-induced cardiotoxicity.

Perioperative transesophageal echocardiography for aortic dissection

PURPOSE

Aortic dissection is an infrequent but serious condition that often requires immediate operative intervention. We explore recent developments in the classification of aortic dissection and perioperative transesophageal echocardiography that assist with quantifying the severity of disease and facilitate its management.

PRINCIPAL FINDINGS

We describe the pivotal role of echocardiography in relation to key surgical considerations such as cannulation, aortic root surgery, perfusion in the aortic arch vessels, stenting in hybrid arch repair, and timing of preventative surgery.

CONCLUSION

Developments in the classification of aortic dissection have improved our perspective and understanding of the key presenting features that affect mortality. Improvements in patient outcome may be achieved in part by appropriately timed echocardiography-guided surgery.

Cerebral vasculitis

The noninfectious, inflammatory vasculitides include giant cell arteritis, Takayasu disease, Churg-Strauss angiitis, Wegener disease, polyarteritis nodosa, microscopic polyangiitis, Buerger disease, amyloid-β-related angiitis, and isolated vasculitis of the central nervous system. While these disorders are relatively uncommon, they produce a variety of neurologic diseases including muscle disease, mononeuropathy multiplex, polyneuropathy, cranial nerve palsies, visual loss, seizures, an encephalopathy, venous thrombosis, ischemic stroke, and intracranial hemorrhage. The multisystem vasculitides often have stereotypical clinical findings that reflect disease of the kidney, sinuses, lungs, skin, joints, or cardiovascular system. These disorders also usually have abnormalities found on serologic testing. Isolated vasculitis of the central nervous system is more difficult to diagnose because the clinical and brain imaging findings are relatively nonspecific. Examination of the cerebrospinal fluid will demonstrate changes consistent with an inflammatory process. Arteriography often shows areas of segmental narrowing affecting multiple intracranial vessels and brain/meningeal biopsy may be required to establish the diagnosis. Management of patients with a multisystem vasculitis or isolated vasculitis of the central nervous system is centered on the administration of immunosuppressive agents. In many cases, corticosteroids remain the mainstay of medical treatment.

Evaluation of the intraoperative specimens of the thoracic and abdominal aorta

BACKGROUND

Little is known about the histological patterns of acute and chronic aortic pathology with regard to medial degeneration, atherosclerosis and aortitis as well as their distribution in different age groups. The aim of the study was to evaluate histopathological findings of intraoperatively gained aortic specimens with regard to the incidence of medial degeneration, atherosclerosis and aortitis.

METHODS

Intraoperatively gained aortic specimens were evaluated in 151 patients including 83 (55%) aortic aneurysms (65 thoracic, 18 abdominal) and 68 (45%) acute type A aortic dissections. Histological stainings used were hematoxylin and eosin, Van Gieson as well as alcian blue. Patients were stratified according to above and below 65 years of age. High grade medial degeneration represented pooling of mucoid material in the whole aortic wall. High grade atherosclerosis represented severe intimal fibrosis, massive accumulation of macrophages and foam cells or massive calcification of the aortic wall.

RESULTS

Medial degeneration was diagnosed in 106 (70%) patients including 55 (52%) aortic aneurysms and 51 (48%) acute type A aortic dissections. High grade medial degeneration was found in 50% of patients with thoracic aortic aneurysms < 65 years of age vs. 44% in patients ≥ 65 years of age (p = 0.64) and in 36% of patients with thoracic aortic dissections < 65 years of age vs. 14% in patients ≥ 65 years of age (p = 0.07). Atherosclerosis was diagnosed in 71 (47%) patients including 46 (65%) aortic aneurysms and 25 (35%) aortic dissections. High grade atherosclerosis was found in 23% of patients with thoracic aneurysms < 65 years of age vs. 36% in patients ≥ 65 years of age (p = 0.24) and in 13% of patients with aortic dissections < 65 years of age vs. 52% in patients ≥ 65 years of age (p < 0.001). Aortitis was rare (n = 2).

CONCLUSIONS

Medial degeneration was the most frequent diagnosis in this series of aortic specimens. Medial degeneration was equally common in patients above and below 65 years of age. However in cases with acute type A aortic dissections, high grade atherosclerosis was the leading histopathological diagnosis in patients older than 65 years. Acute type A aortic dissections seem to have different underlying pathologies in different age groups.

Bicuspid aortic valve and thoracic aortic aneurysm: three patient populations, two disease phenotypes, and one shared genotype

Bicuspid aortic valve (BAV) and thoracic aortic aneurysm (TAA) are two discrete cardiovascular phenotypes characterized by latent progressive disease states. There is a clear association between BAV and TAA; however the nature and extent of this relationship is unclear. There are both distinct and overlapping developmental pathways that have been established to contribute to the formation of the aortic valve and the aortic root, and the mature anatomy of these different tissue types is intimately intertwined. Likewise, human genetics studies have established apparently separate and common contributions to these clinical phenotypes, suggesting complex inheritance and a shared genetic basis and translating 3 patient populations, namely, BAV, TAA, or both, into a common but diverse etiology. A better understanding of the BAV-TAA association will provide an opportunity to leverage molecular information to modify clinical care through more sophisticated diagnostic testing, improved counseling, and ultimately new pharmacologic therapies.

Pathology of the Aorta

The aorta is a distinctive surgical pathology specimen removed most frequently for aneurysm or dissection. Genetic syndromes, inflammatory processes and acquired diseases of aging result in aortic pathology; these are presented in terms of pathology, differential diagnosis and classification schemes. The pathologic context of a variety of commonly encountered histopathologies is described.

Causes and histopathology of ascending aortic disease in children and young adults

BACKGROUND

Ascending aortic diseases (aneurysms, dissections, and stenosis) and associated aortic valve disease are rare but important causes of morbidity and mortality in children and young adults. Certain genetic causes, such as Marfan syndrome and congenital bicuspid aortic valve disease, are well known. However, other rarer genetic and nongenetic causes of aortic disease exist.

METHODS

We performed an extensive literature search to identify known causes of ascending aortic pathology in children and young adults. We catalogued both aortic pathologies and other defining systemic features of these diseases.

RESULTS

We describe 17 predominantly genetic entities that have been associated with thoracic aortic disease in this age group.

CONCLUSIONS

While extensive literature on the common causes of ascending aortic disease exists, there is a need for better histologic documentation of aortic pathology in rarer diseases.

Biomarkers in aortic dissection

Aortic dissection (AD) is a severe cardiovascular disease with high mortality and morbidity, which is characterized by acute onset and rapid progress. Mechanically, it has been considered that circulating blood flows into the media of the aorta through the rupture of the intima forming true and false lumens. Generally, its pathologic process is considered as follows: initially, inflammatory reaction, inflammatory cells infiltration in aortic wall, and then apoptosis of vascular smooth muscle cells, degenerating of aortic media, elastin fracture, and degradation. At last, the ingredients of the aorta are destroyed and lead to aortic dilatation, aneurysm formation, dissection and rupture. Currently, several biomarkers in peripheral blood including C-reactive protein (CRP), matrix metalloproteinases (MMPs), soluble elastin fragments (sELAF), D-dimer, smooth muscle myosin heavy chain, calponin, N-terminal pro-brain natriuretic peptide (NT-proBNP), big endothelin-1 (Big ET-1), genetic markers and so on, have been demonstrated to play a major role in evaluation of AD, for example, making early diagnosis and classifying of AD. Additionally, those markers may also guide our treatment therapies and predict the prognosis. The aims of this review mainly focus on the clinical implications of the biomarkers in AD.

Rare copy number variants disrupt genes regulating vascular smooth muscle cell adhesion and contractility in sporadic thoracic aortic aneurysms and dissections

Thoracic aortic aneurysms and dissections (TAAD) cause significant morbidity and mortality, but the genetic origins of TAAD remain largely unknown. In a genome-wide analysis of 418 sporadic TAAD cases, we identified 47 copy number variant (CNV) regions that were enriched in or unique to TAAD patients compared to population controls. Gene ontology, expression profiling, and network analysis showed that genes within TAAD CNVs regulate smooth muscle cell adhesion or contractility and interact with the smooth muscle-specific isoforms of α-actin and β-myosin, which are known to cause familial TAAD when altered. Enrichment of these gene functions in rare CNVs was replicated in independent cohorts with sporadic TAAD (STAAD, n = 387) and inherited TAAD (FTAAD, n = 88). The overall prevalence of rare CNVs (23%) was significantly increased in FTAAD compared with STAAD patients (Fisher's exact test, p = 0.03). Our findings suggest that rare CNVs disrupting smooth muscle adhesion or contraction contribute to both sporadic and familial disease.

A clinicopathologic study of immunoglobulin G4-related sclerosing disease of the thoracic aorta

OBJECTIVE

Immunoglobulin G4-related sclerosing disease (IgG4-SD) has recently been reported to occur in the cardiovascular system and manifest as inflammatory abdominal aortic aneurysm. Thoracic aortic lesions are often associated with aortitis in several divergent etiologies. Thus, this study was performed to review thoracic aortic lesions from the aspect of IgG4-SD and to elucidate the clinicopathologic characteristics of this subgroup in the thoracic aorta.

METHODS

The study comprised 125 patients, including 71 with thoracic aortic aneurysm (TAA), 44 with aortic dissection, 7 with Takayasu aortitis, and 3 with infectious aortitis. IgG4-SD was identified by diffuse infiltration of numerous IgG4-positive plasmacytes by immunohistochemical examinations. Clinicopathologic features were compared between IgG4-related and IgG4-unrelated lesions.

RESULTS

Among the 125 patients, IgG4-SD was found in 5 patients with TAA but was not detected in the other subgroups of thoracic aortic lesion. IgG4-related TAA included one case of lymphoplasmacytic aortitis, 1 case of inflammatory aneurysm, and three cases of atherosclerotic aneurysms. Patients with IgG4-related TAA showed clinicopathologic features similar to patients with IgG4-SD: male gender, old age, history of bronchial asthma and allergies, elevation of white blood cell counts, C-reactive protein levels, and IgG4 and IgE concentrations (in one patient); eosinophilic infiltration, obliterative phlebitis, lymph follicle formation, and perineural inflammation. In addition, compared with IgG4-unrelated TAA, IgG4-related TAA was characterized by clinically more frequency of involvement of the aortic arch (P = .002), saccular formation (P = .003), and fibrous adhesion to surrounding tissue (P < .001), and histopathologically thicker entire aortic wall and adventitia (P < .001 each).

CONCLUSIONS

IgG4-SD is involved in 4% of all thoracic aortic lesions and uniformly presents in the form of an aneurysm with distinct histologic and clinicopathologic features. IgG4-SD represents one, albeit rare, etiology of TAA, especially those originating in the aortic arch.