GenTAC registry report: Gender differences among individuals with genetically triggered thoracic aortic aneurysm and dissection

Previous data suggest women are at increased risk of death from aortic dissection. Therefore, we analyzed data from the GenTAC registry, the NIH‐sponsored program that collects information about individuals with genetically triggered thoracic aortic aneurysms and cardiovascular conditions. We performed cross‐sectional analyses in adults with Marfan syndrome (MFS), familial thoracic aortic aneurysm or dissection (FTAAD), bicuspid aortic valve (BAV) with thoracic aortic aneurysm or dissection, and subjects under 50 years of age with thoracic aortic aneurysm or dissection (TAAD <50 years). Women comprised 32% of 1,449 subjects and were 21% of subjects with BAV, 34% with FTAAD, 22% with TAAD <50 years, and 47% with MFS. Thoracic aortic dissections occurred with equal gender frequency yet women with BAV had more extensive dissections. Aortic size was smaller in women but was similar after controlling for BSA. Age at operation for aortic valve dysfunction, aneurysm or dissection did not differ by gender. Multivariate analysis (adjusting for age, BSA, hypertension, study site, diabetes, and subgroup diagnoses) showed that women had fewer total aortic surgeries (OR = 0.65, P < 0.01) and were less likely to receive angiotensin converting enzyme inhibitors (ACEi; OR = 0.68, P < 0.05). As in BAV, other genetically triggered aortic diseases such as FTAAD and TAAD <50 are more common in males. In women, decreased prevalence of aortic operations and less treatment with ACEi may be due to their smaller absolute aortic diameters. Longitudinal studies are needed to determine if women are at higher risk for adverse events. © 2013 Wiley Periodicals, Inc.     

Allometric considerations when assessing aortic aneurysms in Turner syndrome: Implications for activity recommendations and medical decision‐making

In Turner syndrome, the potential to form thoracic aortic aneurysms requires routine patient monitoring. However, the short stature that typically occurs complicates the assessment of severity and risk because the relationship of body size to aortic dimensions is different in Turner syndrome compared to the general population. Three allometric formula have been proposed to adjust aortic dimensions, all employing body surface area: aortic size index, Turner syndrome‐specific Z‐scores, and Z‐scores based on a general pediatric and young adult population. In order to understand the differences between these formula we evaluated the relationship between age and aortic size index and compared Turner syndrome‐specific Z‐scores and pediatric/young adult based Z‐scores in a group of girls and women with Turner syndrome. Our results suggest that the aortic size index is highly age‐dependent for those under 15 years; and that Turner‐specific Z‐scores are significantly lower than Z‐scores referenced to the general population. Higher Z‐scores derived from the general reference population could result in stigmatization, inappropriate restriction from sports, and increasing the risk of unneeded medical or operative treatments. We propose that when estimating aortic dissection risk clinicians use Turner syndrome‐specific Z‐score for those under fifteen years of age.

     

Risk factors for aortic valve disease in bicuspid aortic valve: a family-based study

Bicuspid aortic valve (BAV) is the most common cardiovascular malformation and is a risk factor for aortic valve disease (AVD). AVD typically manifests later in life, and the majority of cases have BAV. The purpose of this study was to identify risk factors for AVD in individuals with BAV. Families enriched for BAV were identified in a pediatric population, and echocardiography was performed on all family members. AVD was identified as stenosis and/or insufficiency, and BAV morphology was defined as right–left (RL), right–non (RN) or indeterminate. Heritability (h²) of AVD and BAV morphology was estimated using variance components analysis (SOLAR). To assess AVD risk over time, we used Generalized Estimating Equations methodology (SAS) adjusting for age and gender. A total of 1,128 individuals from 226 families were evaluated. BAV was identified in 281 individuals (25%), and AVD was identified in 167 (59%) individuals with BAV. Previously, we identified a high heritability for BAV (h² = 0.89 ± 0.06, P < 0.00001), but the heritability of AVD in the present study (0.07 ± 0.17, P = 0.33) was low. AVD was significantly associated with BAV morphology (P = 0.0027) and age (P = 0.0068). Children with RN BAV and adults with RL BAV were more likely to develop AVD. BAV is determined largely by genetic effects, but the phenotypic variability of AVD is primarily determined by nongenetic factors. BAV morphology may have predictive value for the time course of AVD. © 2011 Wiley‐Liss, Inc.     

The bicuspid aortic valve and its relation to aortic dilation

BACKGROUND

A bicuspid aortic valve (BAV) is a common congenital heart disease, which affects 1–2% of the population. However, the relationship between BAVs and aortic dilation has not been sufficiently elucidated.

METHODS

A total of 241 BAV patients who were referred to this hospital for cardiac surgey over a 4.75-year period were included in this study. In addition to the clinical characteristics of the included patients, the morphological features of the aortic valve and aorta, the length of the left main coronary artery, and the laboratory findings (the coagulation and hematological parameters as well as the total cholesterol concentration) were determined and compared with those of the tricuspid aortic valve (TAV) patients.

RESULTS

The BAV patients were younger than the TAV patients for a valve surgery in the last 3 months of the study period. The BAV patients were predominantly male. Most of the BAVs that were surgically treated were stenotic, regurgitant, or combined, and only 19 (7.88%) were normally functioning valves. According to echocardiography or operative records, 148 (78.31%) were type A, 31 (16.40%) were type B, and 10 (5.29%) were type C. The left main coronary artery was much shorter in the BAV patients than it was in the TAV patients. There was no significant difference between BAV and TAV patients in the total cholesterol concentrations; whereas differences were noted between patients receiving lipid-lowering therapy and those not receiving lipid-lowering therapy. The dimensions of the aortic root, sinotubular junction, and ascending aorta were beyond normal limits, while they were significantly smaller in the BAV patients than in the TAV patients. They were also much smaller in patients receiving statin therapy than those not receiving statin therapy in both groups. Moreover, the aortic dilation in the BAV group was found to be significantly associated with patient age.

CONCLUSIONS

The BAV patients developed aortic wall and aortic valve disorders at a younger age than the TAV patients and were predominantly male. Aortic dilation was observed in the aortic root, sinotubular junction, and ascending aortic segments in both the BAV and TAV patients undergoing surgical aortic valve replacement, although the BAV patients had a smaller degree of dilation than the TAV patients, and dilation was also significantly age-related in this group. The shorter left main coronary artery that the BAV patients possess may contribute to the progressive course of aortic dilation that these patients experience. Statin therapy did not affect the aortic annulus in either group, but did decrease the dimensions of the aortic root, sinotubular junction and ascending aorta. In general, statin therapy had a better effect on the aortas of the TAV patients than it did on those of the BAV patients.     

Identification of a novel flow-mediated gene expression signature in patients with bicuspid aortic valve

Individuals with bicuspid aortic valve (BAV) are at significantly higher risk of developing serious aortic complications than individuals with tricuspid aortic valves (TAV). Studies have indicated an altered aortic blood flow in patients with BAV; however, the extent to which altered flow influences the pathological state of BAV aorta is unclear. In the present study, we dissected flow-mediated aortic gene expression in patients undergoing elective open heart surgery. A large collection of public microarray data sets were firstly screened for consistent co-expression with five well-characterized flow-regulated genes (query genes). Genes with co-expression probability of >0.5 were selected and further analysed in expression profiles (127 arrays) from ascending aorta of BAV and TAV patients. Forty-four genes satisfied two filtering criteria: a significant correlation with one or more of the query genes (R?>?0.40) and differential expression between patients with BAV and TAV. No gene fulfilled the criteria in mammary artery (88 arrays), an artery not in direct contact with the valve. Fifty-five percent of the genes significantly altered between BAV and TAV patients showed differential expression between two identified flow regions in the rat aorta. A large proportion of the identified genes were related to angiogenesis and/or wound healing, with pro-angiogenesis genes downregulated and inhibitory genes upregulated in patients with BAV. Moreover, differential expression of ZFP36, GRP116 and PKD2 was confirmed using immunohistochemistry. Implementing a new strategy, we have demonstrated an angiostatic gene expression signature in patients with BAV, indicating impaired wound healing in these patients, potentially involved in BAV-associated aortopathy.     

经胸超声心动图无创性评价先天性主动脉瓣病变

目的 评价经胸超声心动图在诊断先天性主动脉瓣病变中的应用价值.方法 临床确诊的先天性主动脉瓣病变患者43例,其中男性25例,女性18例;年龄4～46岁,平均年龄234岁.纯合子家族性高胆固醇血症(HoFH)患者7例,主动脉瓣二叶畸形(BAV)患者35例,罕见的主动脉瓣下移畸形1例.回顾分析经胸超声心动图检查结果,并与彩...     

Cantu syndrome: A longitudinal review of vascular findings in three individuals

Cantu syndrome is a rare autosomal dominant disorder caused by missense variants in ABCC9 and KCNJ8. It is characterized by hypertrichosis, neonatal macrosomia, coarse facial features, and skeletal anomalies. Reported cardiovascular anomalies include cardiomegaly, structural defects, collateral vessels, and rare report of arteriovenous malformation (AVM). Arterial dilation is reported in a few individuals including one with surgical intervention for a thoracic aortic aneurysm. The natural history of this aortopathy including the rate of progression or risk for dissection is unknown and longitudinal patient data is unavailable. We present data from vascular imaging in three individuals with genetically confirmed Cantu syndrome over 3 to 14 years of follow‐up. All patients had generally stable aortic dilation, which did not reach the surgical threshold, including one individual followed closely through pregnancy. In adulthood, one individual had a maximum ascending aortic measurement of 4.2 cm. Two pediatric patients had aortic root or ascending z‐scores of approximately +3. A large asymptomatic pelvic AVM was identified in one individual on head‐pelvis MRI. While the data reported in these individuals is reassuring regarding the risk for progressive disease, further data from additional individuals with Cantu syndrome is needed to best inform screening recommendations, improve understanding of dissection risk, and guide management.     

Architectural Trends in the Human Normal and Bicuspid Aortic Valve Leaflet and Its Relevance to Valve Disease

The bicuspid aortic valve (AV) is the most common cardiac congenital anomaly and has been found to be a significant risk factor for developing calcific AV disease. However, the mechanisms of disease development remain unclear. In this study we quantified the structure of human normal and bicuspid leaflets in the early disease stage. From these individual leaflet maps average fiber structure maps were generated using a novel spline based technique. Interestingly, we found statistically different and consistent regional structures between the normal and bicuspid valves. The regularity in the observed microstructure was a surprising finding, especially for the pathological BAV leaflets and is an essential cornerstone of any predictive mathematical models of valve disease. In contrast, we determined that isolated valve interstitial cells from BAV leaflets show the same in vitro calcification pathways as those from the normal AV leaflets. This result suggests the VICs are not intrinsically different when isolated, and that external features, such as abnormal microstructure and altered flow may be the primary contributors in the accelerated calcification experienced by BAV patients.     

Biomechanical characterization of ascending aortic aneurysm with concomitant bicuspid aortic valve and bovine aortic arch

Studies have shown that patients harboring bicuspid aortic valve (BAV) or bovine aortic arch (BAA) are more likely than the general population to develop ascending aortic aneurysm (AsAA). A thorough quantification of the AsAA tissue properties for these patient groups may offer insights into the underlying mechanisms of AsAA development. Thus, the objective of this study was to investigate and compare the mechanical and microstructural properties of aortic tissues from AsAA patients with and without concomitant BAV or BAA. AsAA (n = 20), BAV (n = 20) and BAA (n = 15) human tissues were obtained from patients who underwent elective AsAA surgery. Planar biaxial and uniaxial failure tests were used to characterize the mechanical and failure properties of the tissues, respectively. Histological analysis was performed to detect medial degenerative characteristics of aortic aneurysm. Individual layer thickness and composition were quantified for each patient group. The circumferential stress–strain response of the BAV samples was stiffer than both AsAA (p = 0.473) and BAA (p = 0.152) tissues at a low load. The BAV samples were nearly isotropic, while AsAA and BAA samples were anisotropic. The areal strain of BAV samples was significantly less than that of AsAA (p = 0.041) and BAA (p = 0.004) samples at a low load. The BAA samples were similar to the AsAA samples in both mechanical and failure properties. On the microstructural level, all samples displayed moderate medial degeneration, characterized by elastin fragmentation, cell loss, mucoid accumulation and fibrosis. The ultimate tensile strength of BAV and BAA sampleswere also found to decrease with age. Overall, the BAV samples were stiffer than both AsAA and BAA samples, and the BAA samples were similar to the AsAA samples. The BAV samples were thinnest, with less elastin than AsAA and BAA samples, which may be attributed to the loss of extensibility of these tissues at a low load. No apparent difference in failure mechanics among the tissue groups suggests that each of the patient groups may have a similar risk of rupture.     

Clinical characteristics and rate of dilatation in Turner syndrome patients treated for aortic dilatation

Turner syndrome is associated with an increased risk of aortic aneurysms and dissection. Recent 2017 clinical care guidelines recommend medical therapy to treat aortic dilatation, although whether this slows dilatation is unknown. We aimed to describe a pre‐guideline cohort of Turner syndrome patients with aortic dilatation, the rate of dilatation following diagnosis, and post therapy dilatation rates. We conducted a retrospective review of Turner syndrome patients with a dilated aortic root or ascending aorta by current definitions. In total, 40 patients were included with 22 treated patients. Most patients had 45,X karyotype, were white, non‐Hispanic, and received both growth hormone and estrogen. Except for hypertension, there were no differences in risk factors among treated and untreated groups. Bicuspid aortic valve was very common. Treatment group patients had significantly more dilated ascending aortas by absolute measurements and aortic size index. In an adjusted model, there was minimal change in aortic measures over time and this was not associated with medication use. In conclusion, in this cohort, Turner syndrome patients with aortic dilatation were more likely to be treated if they had hypertension and if they met multiple dilatation criteria. Further study is needed to establish medical therapy efficacy on dilatation progression.     

Digital vascular lesions detected by transillumination

Abnormalities of the capillaries of the digits in hereditary hemorrhagic telangiectasia can be detected by shining through a narrow beam of light through the dorsal side and visualizing the vasculature on the palmar side, a procedure termed transillumination. This study was performed to determine if this method can detect digital vascular abnormalities in aortopathies and arteriopathies. Transillumination was performed in patients with Marfan syndrome (MFS), thoracic aortic aneurysm and dissection (TAAD), vascular Ehlers–Danlos syndrome (vEDS), bicuspid aortic valve with aortopathy, and arteriopathies without aortopathy. Subjects with no known vascular disorders were controls. Digital vascular abnormalities were present in some patients with all of the disorders and were especially frequent in MFS, TAAD, and vEDS. All patients had significantly more digital vascular abnormalities than control subjects. Transillumination can detect vascular abnormalities in digits of patients with a variety of conditions with aortopathy or arteriopathy.     

Ectopia lentis in Loeys‐Dietz syndrome type 4

Loeys‐Dietz syndrome is a heritable disorder of the connective tissue leading to multisystem involvement including craniofacial features, skeletal abnormalities, cutaneous findings and early‐onset and aggressive disease of the aorta and its branches. There are multiple types of Loeys‐Dietz syndrome related to pathogenic variants in TGFBR1, TGFBR2, SMAD3, TGFB2, and TGFB3. Individuals with Loeys‐Dietz syndrome may be misdiagnosed as having Marfan syndrome due to shared phenotypic features and aortic root dilation. However, ectopia lentis has been an important discriminating feature, being unique to Marfan syndrome and not reported to be associated with Loeys‐Dietz syndrome. We report the case of a 46‐year‐old woman with Loeys‐Dietz syndrome type 4 due to a pathogenic variant in TGFB2 who was diagnosed with ectopia lentis at age 44. The patient underwent whole exome sequencing and no other pathogenic variants were found to explain the ectopia lentis. Our findings indicate that ectopia lentis may be an uncommon finding in Loeys‐Dietz syndrome type 4 and emphasize the importance of genetic testing in familial thoracic aortic aneurysm disease.     

Higher rate of aortic stenosis progression in patients with bicuspid versus tricuspid aortic valve – A single center experience

PurposeWe sought to investigate aortic stenosis (AS) progression rate (pr) with the comparison between bicuspid aortic valve (BAV) and tricuspid aortic valve (TAV) morphology.Materials and methodsWe compared ASpr in patients with BAV and TAV examined by transthoracic echocardiography (TTE) in the years 2004–2019.ResultsData from 363 TTEs in 161 AS patients (median age 70 [61–77] years; 63% men; 25% with BAV; 20% with severe AS) performed at different time points (median time interval 10 months) was analyzed. We assessed changes of AS severity with peak velocity through aortic valve (Vmax), mean/peak pressure gradients (MG/PG), aortic valve area by planimetry and continuity equation (AVAce). We compared pr (defined as parameter change per year) between the BAV and the TAV groups. BAV patients showed faster ASpr with odds ratio 3.467 and 95% confidence intervals 1.36 to 8.86, moreover, expressed as a quicker AVAce decrease 0 (−0.4-0.0) in the BAV vs. 0 (−0.15 – 0.0) cm²/year in the TAV group, p ​= ​0.02. Furthermore, in BAV, female sex was associated with lower ASpr (p ​= ​0.01), and in the whole group a larger aortic diameter was a predictor of faster progression (p ​< ​0.001).ConclusionThe ASpr, expressed as a decrease in the AVAce, was faster in BAV. Moreover, ASpr depends on both: valve morphology being faster in BAV and Vmax increase. Furthermore, the female sex was related to slower pace of AVA reduction in BAV subgroup whereas the larger baseline aortic diameter associated to faster AS progression in the whole studied group.     

Short stature in a mother and daughter caused by familial der(X)t(X;X)(p22.1‐3;q26)

Deletions of the terminal Xp regions, including the short‐stature homeobox (SHOX) gene, were described in families with hereditary Turner syndrome and Léri‐Weill syndrome. We report on a 10‐2/12‐year‐old girl and her 37‐year‐old mother with short stature and no other phenotypic symptoms. In the daugther, additional chromosome material was detected in the pseudoautosomal region of one X chromosome (46,X,add(Xp.22.3)) by chromosome banding analysis. The elongation of the X chromosome consisted of Giemsa dark and bright bands with a length one‐fifth of the size of Xp. The karyotype of the mother demonstrated chromosome mosaicism with three cell lines (46,X,add(X)(p22.3) [89]; 45,X [8]; and 47,X,add(X)(p22.3), add(X)(p22.3) [2]). In both daughter and mother, fluorescence in situ hybridization (FISH), together with data from G banding, identified the breakpoints in Xp22.1‐3 and Xq26, resulting in a partial trisomy of the terminal region of Xq (Xq26‐qter) and a monosomy of the pseudoautosomal region (Xp22.3) with the SHOX gene and the proximal region Xp22.1‐3, including the steroidsulfatase gene (STS) and the Kallmann syndrome region. The derivative X chromosome was defined as ish.der(X)t(X;X)(p22.1‐3;q26)(yWXD2540‐, F20cos‐, STS‐, 60C10‐, 959D10‐, 2771+, cos9++). In daughter and mother, the monosomy of region Xp22.1‐3 is compatible with fertility and does not cause any other somatic stigmata of the Turner syndrome or Léri‐Weill syndrome, except for short stature due to monosomy of the SHOX gene. © 2001 Wiley‐Liss, Inc.     

Familial congenital bicuspid aortic valve: A disorder of uncertain inheritance

Congenital bicuspid aortic valve (BAV) is one of the most frequent heart defects detected by echocardiographic investigation and necropsy (0.9–1% of the general population), but only 16 families with familial congenital BAV have been described up to now. We report on a family in which 4 members of two generations (2 brothers, 1 sister, and her son) are affected with BAV. The BAV mode of inheritance is discussed. © 1996 Wiley-Liss, Inc.     

Overlapping but distinct roles for NOTCH receptors in human cardiovascular disease

The NOTCH signalling pathway is an essential pathway, involved in many cellular processes, including cell fate decision, cell proliferation, and cell death and important in the development of most organs. Mutations in genes encoding components of the NOTCH signalling pathway lead to a spectrum of congenital disorders. Over the past decades, mutations in human NOTCH signalling genes have been identified in several diseases with cardiovascular involvement. NOTCH1 mutations have been described in bicuspid aortic valve disease, left-sided congenital heart disease, and Adams-Oliver syndrome. NOTCH2 mutations lead to the development of Alagille syndrome, while mutations in NOTCH3 cause cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy. To date, mutations in NOTCH4 have not been associated with cardiovascular disease. This review focuses on the mutations described in NOTCH1, NOTCH2, and NOTCH3 and their associated cardiovascular phenotypes.     

Thoracic aortic disease in two patients with juvenile polyposis syndrome and SMAD4 mutations

Dilation or aneurysm of the ascending aorta can progress to acute aortic dissection (Thoracic Aortic Aneurysms and Aortic Dissections, TAAD). Mutations in genes encoding TGF‐β‐related proteins (TGFBR1, TGFBR2, FBN1, and SMAD3) cause syndromic and inherited TAAD. SMAD4 mutations are associated with juvenile polyposis syndrome (JPS) and a combined JPS–hereditary hemorrhagic telangiectasia (HHT) known as JPS–HHT. A family with JPS–HHT was reported to have aortic root dilation and mitral valve abnormalities. We report on two patients with JPS–HHT with SMAD4 mutations associated with thoracic aortic disease. The first patient, an 11‐year‐old boy without Marfan syndrome features, had JPS and an apparently de novo SMAD4 mutation (c.1340_1367dup28). Echocardiography showed mild dilation of the aortic annulus and aortic root, and mild dilation of the sinotubular junction and ascending aorta. Computed tomography confirmed aortic dilation and showed small pulmonary arteriovenous malformations (PAVM). The second patient, a 34‐year‐old woman with colonic polyposis, HHT, and features of Marfan syndrome, had a SMAD4 mutation (c.1245_1248delCAGA). Echocardiography showed mild aortic root dilation. She also had PAVM and hepatic focal nodular hyperplasia. Her family history was significant for polyposis, HHT, thoracic aortic aneurysm, and dissection and skeletal features of Marfan syndrome in her father. These two cases confirm the association of thoracic aortic disease with JPS–HHT resulting from SMAD4 mutations. We propose that the thoracic aorta should be screened in patients with SMAD4 mutations to prevent untimely death from dissection. This report also confirms that SMAD4 mutations predispose to TAAD. © 2012 Wiley Periodicals, Inc.     

Inheritance analysis of congenital left ventricular outflow tract obstruction malformations: Segregation, multiplex relative risk, and heritability

The left ventricular outflow tract (LVOTO) malformations, aortic valve stenosis (AVS), coarctation of the aorta (COA), and hypoplastic left heart (HLH) constitute a mechanistically defined subgroup of congenital heart defects that have substantial evidence for a genetic component. Evidence from echocardiography studies has shown that bicuspid aortic valve (BAV) is found frequently in relatives of children with LVOTO defects. However, formal inheritance analysis has not been performed. We ascertained 124 families by an index case with AVS, COA, or HLH. A total of 413 relatives were enrolled in the study, of which 351 had detailed echocardiography exams for structural heart defects and measurements of a variety of aortic arch, left ventricle, and valve structures. LVOTO malformations were noted in 30 relatives (18 BAV, 5 HLH, 3 COA, and 3 AVS), along with significant congenital heart defects (CHD) in 2 others (32/413; 7.7%). Relative risk for first-degree relatives in this group was 36.9, with a heritability of 0.71-0.90. Formal segregation analysis suggests that one or more minor loci with rare dominant alleles may be operative in a subset of families. Multiplex relative risk analysis, which estimates number of loci, had the highest maximum likelihood score in a model with 2 loci (range of 1-6 in the lod-1 support interval). Heritability of several aortic arch measurements and aortic valve was significant. These data support a complex but most likely oligogenic pattern of inheritance. A combination of linkage and association study designs is likely to enable LVOTO risk gene identification. This data can also provide families with important information for screening asymptomatic relatives for potentially harmful cardiac defects.