Dissection of the aorta in Turner syndrome: two cases and review of 85 cases in the literature

Emergency vascular surgical care in populations with unique physiologic characteristics: Pediatric, pregnant, and frail populations

Vascular surgical emergencies are common in vascular surgical care and require complex decision making and multidisciplinary care. They are especially challenging when they occur in patients with unique physiological characteristics, such as pediatric, pregnant, and frail patients. Among the pediatric and pregnant population, vascular emergencies are rare. This rarity challenges accurate and timely diagnosis of the vascular emergency. This landscape review summarizes these three unique populations' epidemiology and emergency vascular considerations. Understanding the epidemiology is the foundation for accurate diagnosis and subsequent management. Considering each population's unique characteristics is crucial to the emergent vascular surgical interventions decision making. Collaborative and multidisciplinary care is vital in gaining expertise in managing these special populations and achieving optimal patient outcomes.

Genetics of Heritable Thoracic Aortic Disease

Genetic testing plays an increasing diagnostic and prognostic role in the management of patients with heritable thoracic aortic disease (HTAD). The identification of a specific variant can establish or confirm the diagnosis of syndromic HTAD, dictate extensive evaluation of the arterial tree in HTAD with known distal vasculature involvement and justify closer follow-up and earlier surgical intervention in HTAD with high risk of dissection of minimal or normal aortic size. Evolving phenotype–genotype correlations lead us towards more precise and individualized management and treatment of patients with HTAD. In this review, we present the latest evidence regarding the role of genetics in patients with HTAD.

Murmurs other than the early diastolic murmur in aortic dissection

The purpose of this review is to draw attention to the presence and significance of murmurs other than the murmur of aortic regurgitation, in patients with aortic dissection. For that purpose, a literature search was conducted using Pubmed and Googlescholar. The search terms were "dissecting aneurysm of the aorta", "systolic murmurs", "ejection systolic murmurs", "holosystolic" murmurs, "continuous murmurs", and "Austin-Flint" murmur. Murmurs other than the murmur of aortic regurgitation, which were associated with aortic dissection, fell into the categories of systolic murmurs, some of which were holosystolic, and continuous murmurs, the latter attributable to fistulae between the dissecting aneurysm and the left atrium, right atrium, and the pulmonary artery, respectively. Mid-diastolic murmurs were also identified, and these typically occurred in association with both the systolic and the early diastolic murmurs. Among patients with systolic murmurs clinical features which enhanced the pre-test probability of aortic dissection included back pain, stroke, paraplegia, unilateral absence of pulses, interarm differences in blood pressure, hypertension, shock, bicuspid aortic valve, aortic coarctation, Turner's syndrome, and high D-dimer levels, respectively. In the absence of the murmur of aortic regurgitation timely diagnosis of aortic dissection could be expedited by increased attention to parameters which enhance pretest probability of aortic dissection. That logic would apply even if the only murmurs which were elicited were systolic murmurs.

Aortic Root Dilatation in Taiwanese Patients with Mucopolysaccharidoses and the Long-Term Effects of Enzyme Replacement Therapy

Background: Cardiovascular abnormalities have been observed in patients with mucopolysaccharidosis (MPS) of any type, with the most documented abnormalities being valvular regurgitation and stenosis and cardiac hypertrophy. Only a few studies have focused on aortic root dilatation and the long-term effects of enzyme replacement therapy (ERT) in these patients. Methods: We reviewed echocardiograms of 125 Taiwanese MPS patients (age range, 0.1 to 19.1 years; 11 with MPS I, 49 with MPS II, 25 with MPS III, 29 with MPS IVA, and 11 with MPS VI). The aortic root diameter was measured at the sinus of Valsalva. Results: Aortic root dilatation (z score >2) was observed in 47% of the MPS patients, including 66% of MPS IV, 51% of MPS II, 45% of MPS VI, 28% of MPS III, and 27% of MPS I patients. The mean aortic root diameter z score was 2.14 (n = 125). The patients with MPS IV had the most severe aortic root dilatation with a mean aortic root diameter z score of 3.03, followed by MPS II (2.12), MPS VI (2.06), MPS III (1.68), and MPS I (1.03). The aortic root diameter z score was positively correlated with increasing age (n = 125, p < 0.01). For the patients with MPS II, III, and IV, aortic root diameter z score was also positively correlated with increasing age (p < 0.01). For 16 patients who had received ERT and had follow-up echocardiographic data (range 2.0–16.2 years), the mean aortic root diameter z score change was −0.46 compared to baseline (baseline 2.49 versus follow-up 2.03, p = 0.490). Conclusions: Aortic root dilatation was common in the patients with all types of MPS, with the most severe aortic root dilatation observed in those with MPS IV. The severity of aortic root dilatation worsened with increasing age, reinforcing the concept of the progressive nature of this disease. ERT for MPS appears to stabilize the progression of aortic root dilatation.

The Role of Genetics in Risk Stratification of Thoracic Aortic Aneurysm Dissection

Thoracic aortic aneurysms are prevalent in the Western population and are often caused by genetic defects. If undetected, aneurysms can dissect or rupture, which are events associated with a high mortality rate. Hitherto no cure exists other than elective surgery if aneurysm dimensions reach a certain threshold. In the past decades, genotype-phenotype associations have emerged that enable clinicians to start stratifying patients according to risk for dissection. Nonetheless, risk assessment is—to this day—confounded by the lack of full comprehension of underlying genetics and modifying genetic risk factors that complicate the yet established genotype-phenotype correlations. Further research that focuses on identifying these additional risk markers is crucial.

Genetics in bicuspid aortic valve disease: Where are we?

Bicuspid aortic valve (BAV) is the most common congenital heart defect, found in up to 2% of the population and associated with a 30% lifetime risk of complications. BAV is inherited as an autosomal dominant trait with incomplete penetrance and variable expressivity due to a complex genetic architecture that involves many interacting genes. In this review, we highlight the current state of knowledge about BAV genetics, principles and methods for BAV gene discovery, clinical applications of BAV genetics, and important future directions.

Age- and Sex-Related Aortic Valve Dysfunction and Aortopathy Difference in Patients with Bicuspid Aortic Valve

Bicuspid aortic valve (BAV) is the most common congenital heart disease. Different distribution of valve dysfunction was found in patients with BAV in different age and sex groups, but related difference was not well established. The aim of our study is to investigate age- and sex-related clinical characteristics differences in patients with BAV.Six hundred twenty patients with BAV who had moderate or severe aortic valve dysfunction were included in the study. Basic clinical data and image data were recorded. Patients were classified into four different age groups: (A: ≤ 50 years old; B: 50-60 years old; C: 60-70 years old; D: > 70 years old). The sex-related clinical difference in different age groups was compared. Association between incidence of aortic valve dysfunction and age was evaluated.Male patients had more frequent aortic regurgitation (AR) in patients younger than 70 years old (A: 52.3% versus 20.0%, P = 0.012; B: 43.2% versus 17.8%, P < 0.001; C: 17.0 versus 2.6%, P = 0.002), whereas female patients were more likely to have aortic stenosis (AS) (A: 75.0% versus 34.1%, P = 0.001; B: 77.8% versus 37.0%, P < 0.001; C: 93.6% versus 69.8%, P < 0.001). Frequency of AR in male patients decreased with age, whereas frequency of AS increased. Trend test showed a significant difference in incidence of aortic valve dysfunction as age increased in male patients (AR, P < 0.001; AS, P < 0.001). No trend was found in female patients.Male patients with BAV present more often with moderate/severe AR at a young age, and the frequency of AR decreases with age. Female patients with BAV had more frequent AS at first presentation regardless of age.

Aortic root dilatation in patients with mucopolysaccharidoses and the impact of enzyme replacement therapy

Mucopolysaccharidoses (MPS) are disorders characterized by impaired glycosaminoglycan (GAG) catabolism as a consequence of a deficiency or the absence of lysosomal enzymes directly involved in their degradation. Multiple organ systems are involved in MPS, including the cardiovascular system. Recently, aortic root dilatation (ARD) has been described in these patients. Thus, we reviewed aortic root diameter measurements in 69 MPS patients from a single center from 2000 to 2016. Aortic root diameter z scores were calculated based on data published by Colan et al. according to the body surface area (BSA) determined using the Haycock formula. The overall incidence of ARD in MPS patients was 39.1%. Higher mean z scores were present in patients with MPS IVA and VI when compared to MPS I and II. Aortic root z scores were higher in older MPS IVA patients, which may suggest a progressive ARD change in this MPS type. No significant differences were found before and after enzyme replacement therapy (ERT) in 11 patients with available data (2 with MPS I; 4 with MPS II; 2 with MPS IVA, and 3 with MPS VI). This work provides further evidence that ARD is common in different types of MPS, being especially evident in MPS IVA, but with a significant occurrence also in MPS VI.

Aortic dissection in patients with Marfan syndrome based on the IRAD data

Between January 1996 and May 2017, the International Registry on Acute Aortic Dissections has collected information on a total of 6,424 consecutive patients with acute aortic dissection, including 258 individuals with a diagnosis of Marfan syndrome. Patients with Marfan syndrome presented at a significantly younger age compared to patients without Marfan syndrome (38.2±13.2 vs. 63.0±14.0 years; P<0.001) and in general had fewer comorbidities, although they more frequently had a known aortic aneurysm and history of prior cardiac surgery. We noted significantly larger diameters of the aortic annulus and root in the Marfan syndrome cohort, but no larger diameters more distally. The in-hospital mortality in type A dissection was not significantly different in patients with or without Marfan syndrome, despite the differences in age and comorbidities and the lower incidence of aortic rupture in the Marfan syndrome cohort. In contrast, the in-hospital mortality of Marfan syndrome patients with type B dissection appears to be lower than that of patients without Marfan syndrome. The Marfan syndrome cohort that was treated with open surgery for type B dissection seemed to do especially well, with a 0% mortality rate (n=27). Follow-up data for type A and B dissections combined show an estimated five-year survival rate of 80.1% and an estimated reintervention rate of 55.3% in patients with Marfan syndrome. Such a high rate of reinterventions highlights the need for careful surveillance and treatment for patients with Marfan syndrome surviving the acute phase of aortic dissection.

Managing subfertility in patients with heart disease: What are the choices?

More women with heart disease are reaching reproductive age and will want to embark upon pregnancy. Furthermore, many of these women are delaying pregnancy until later in life when they may be exposed to a greater number of complications from their heart disease. A relatively high proportion of these women will pursue fertility treatment to achieve a pregnancy; consequently, the management of subfertile couples where the woman (or man) has heart disease is of growing importance. In this review, we discuss how fertility investigations and treatment can impact a women with heart disease and how some of the potential complications can be minimized or avoided. We also consider surrogacy, which is an important option when pregnancy is contraindicated.

Autosomal and X chromosome structural variants are associated with congenital heart defects in Turner syndrome: The NHLBI GenTAC registry

Turner Syndrome (TS) is a developmental disorder caused by partial or complete loss of one sex chromosome. Bicuspid aortic valve and other left-sided congenital heart lesions (LSL), including thoracic aortic aneurysms and acute aortic dissections, are 30-50 times more frequent in TS than in the general population. In 454 TS subjects, we found that LSL are significantly associated with reduced dosage of Xp genes and increased dosage of Xq genes. We also showed that genome-wide copy number variation is increased in TS and identify a common copy number variant (CNV) in chromosome 12p13.31 that is associated with LSL with an odds ratio of 3.7. This CNV contains three protein-coding genes (SLC2A3, SLC2A14, and NANOGP1) and was previously implicated in congenital heart defects in the 22q11 deletion syndrome. In addition, we identified a subset of rare and recurrent CNVs that are also enriched in non-syndromic BAV cases. These observations support our hypothesis that X chromosome and autosomal variants affecting cardiac developmental genes may interact to cause the increased prevalence of LSL in TS. © 2016 Wiley Periodicals, Inc.

The Expanding Clinical Spectrum of Extracardiovascular and Cardiovascular Manifestations of Heritable Thoracic Aortic Aneurysm and Dissection

More than 30 heritable conditions are associated with thoracic aortic aneurysm and dissection (TAAD). Heritable syndromic conditions, such as Marfan syndrome, Loeys-Dietz syndrome, and vascular Ehlers-Danlos syndrome, have somewhat overlapping systemic features, but careful clinical assessment usually enables a diagnosis that can be validated with genetic testing. Nonsyndromic FTAAD can also occur and in 20%-25% of these probands mutations exist in genes that encode elements of the extracellular matrix, signalling pathways (especially involving transforming growth factor-β), and vascular smooth muscle cytoskeletal and contractile processes. Affected individuals with either a syndromic presentation or isolated TAAD can have mutations in the same gene. In this review we focus on the genes currently known to have causal mutations for syndromic and isolated FTAAD and outline the range of associated extracardiovascular and cardiovascular manifestations with each.

A roadmap to investigate the genetic basis of bicuspid aortic valve and its complications: insights from the International BAVCon (Bicuspid Aortic Valve Consortium)

Bicuspid aortic valve (BAV) is the most common adult congenital heart defect and is found in 0.5% to 2.0% of the general population. The term "BAV" refers to a heterogeneous group of disorders characterized by diverse aortic valve malformations with associated aortopathy, congenital heart defects, and genetic syndromes. Even after decades of investigation, the genetic determinants of BAV and its complications remain largely undefined. Just as BAV phenotypes are highly variable, the genetic etiologies of BAV are equally diverse and vary from complex inheritance in families to sporadic cases without any evidence of inheritance. In this paper, the authors discuss current concepts in BAV genetics and propose a roadmap for unraveling unanswered questions about BAV through the integrated analysis of genetic and clinical data.

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.

The patient with Turner syndrome: puberty and medical management concerns

Turner syndrome (TS), which affects approximately 1 in 2,500 live-born females, is characterized by loss or structural anomalies of an X chromosome. Clinical features vary among patients; multiple organ systems can be affected. Endocrinologists are involved in the management of short stature, delayed puberty, and infertility. Endocrine therapies can include growth hormone, estrogen, and progestogen to promote linear growth and pubertal development. The duration of estrogen and progestogen treatment hormone treatment (HT) is generally more than 40 years. No one standard HT is suitable for all women, so general guidelines are provided to induce pubertal development. Additional considerations regarding HT choice include thrombotic risk and disorders associated with thrombophilia. Involvement of cardiologists is important because approximately 50% of patients with TS have congenital structural cardiac anomalies linked to an increased risk for aortic dissection and rupture. Oocyte donation offers the chance to carry a pregnancy, but accumulating information has highlighted the potential dangers associated with pregnancy. Advances in the care of infants, girls, and women with TS have been achieved; management involves coordinated care from a multidisciplinary team including endocrinologists, cardiologists, geneticists, otolaryngologists, behavioral health experts, nurse educators, and social workers.