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The tracking of objects and person position, orientation, and movement is relevant for various medical use cases, e.g., practical training of medical staff or patient rehabilitation. However, these demand high tracking accuracy and occlusion robustness. Expensive professional tracking systems fulfill these demands, however, cost-efficient and potentially adequate alternatives can be found in the gaming industry, e.g., SteamVR Tracking. This work presents an evaluation of SteamVR Tracking in its latest version 2.0 in two experimental setups, involving two and four base stations. Tracking accuracy, both static and dynamic, and occlusion robustness are investigated using a VIVE Tracker (3.0). A dynamic analysis further compares three different velocities. An error evaluation is performed using a Universal Robots UR10 robotic arm as ground-truth system under nonlaboratory conditions. Results are presented using the Root Mean Square Error. For static experiments, tracking errors in the submillimeter and subdegree range are achieved by both setups. Dynamic experiments achieved errors in the submillimeter range as well, yet tracking accuracy suffers from increasing velocity. Four base stations enable generally higher accuracy and robustness, especially in the dynamic experiments. Both setups enable adequate accuracy for diverse medical use cases. However, use cases demanding very high accuracy should primarily rely on SteamVR Tracking 2.0 with four base stations.

Background: The GenTAC (Genetically Triggered Thoracic Aortic Aneurysm and Cardiovascular Conditions) Registry enrolled patients with genetic aortopathies between 2007 and 2016., Objectives: The purpose of this study was to compare age distribution and probability of elective surgery for proximal aortic aneurysm, any dissection surgery, and cardiovascular mortality among aortopathy etiologies., Methods: The GenTAC study had a retrospective/prospective design. Participants with bicuspid aortic valve (BAV) with aneurysm (n = 879), Marfan syndrome (MFS) (n = 861), nonsyndromic heritable thoracic aortic disease (nsHTAD) (n = 378), Turner syndrome (TS) (n = 298), vascular Ehlers-Danlos syndrome (vEDS) (n = 149), and Loeys-Dietz syndrome (LDS) (n = 121) were analyzed., Results: The 25% probability of elective proximal aortic aneurysm surgery was 30 years for LDS (95% CI: 18-37 years), followed by MFS (34 years; 95% CI: 32-36 years), nsHTAD (52 years; 95% CI: 48-56 years), and BAV (55 years; 95% CI: 53-58 years). Any dissection surgery 25% probability was highest in LDS (38 years; 95% CI: 33-53 years) followed by MFS (51 years; 95% CI: 46-57 years) and nsHTAD (54 years; 95% CI: 51-61 years). BAV experienced the largest relative frequency of elective surgery to any dissection surgery (254/33 = 7.7), compared with MFS (273/112 = 2.4), LDS (35/16 = 2.2), or nsHTAD (82/76 = 1.1). With MFS as the reference population, risk of any dissection surgery or cardiovascular mortality was lowest in BAV patients (HR: 0.13; 95% CI: 0.08-0.18; HR: 0.13; 95%: CI: 0.06-0.27, respectively). The greatest risk of mortality was seen in patients with vEDS., Conclusions: Marfan and LDS cohorts demonstrate age and event profiles congruent with the current understanding of syndromic aortopathies. BAV events weigh toward elective replacement with relatively few dissection surgeries. Nonsyndromic HTAD patients experience near equal probability of dissection vs prophylactic surgery, possibly because of failure of early diagnosis., Competing Interests: Funding Support and Author Disclosures The GenTAC (Genetically Triggered Thoracic Aortic Aneurysms and Cardiovascular Conditions) Registry has been supported by U.S. Federal Government contracts HHSN268200648199C and HHSN268201000048C from the National Heart, Lung, and Blood Institute and the National Institute of Arthritis and Musculoskeletal and Skin Diseases. Dr LeMaire has served as a consultant for Terumo Aortic and Cerus; and has served as a principal investigator for clinical studies sponsored by Terumo Aortic and CytoSorbents. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2022 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Objective: To evaluate long-term survival in patients with Turner syndrome after congenital heart surgery with a focus on left heart obstructive lesions (LHOLs)., Study Design: We queried the Pediatric Cardiac Care Consortium, a US-based registry of congenital heart surgery, for patients with Turner syndrome undergoing congenital heart surgery at <21 years of age between 1982 and 2011. Outcomes were obtained from the Pediatric Cardiac Care Consortium and from national death and transplant registries through 2019. Survival of patients with Turner syndrome and nonsyndromic patients with similar LHOL was compared by Kaplan-Meier survival curves and Cox regression adjusted for age, congenital heart disease, and era., Results: We identified 179 patients with Turner syndrome operated for LHOL: 161 with 2-ventricle lesions (coarctation n = 149, aortic stenosis n = 12) and 18 with hypoplastic left heart (HLH) variants. There were 157 with 2-ventricle LHOL and 6 with HLH survived to discharge. Among survivors to hospital discharge, the 30-year transplant-free survival was 90.4% for Turner syndrome with 2-ventricle lesions and 90.9% for nonsyndromic comparators (adjusted hazard ratio [aHR] 1.15, 95% CI 0.64-2.04). The postdischarge survival for HLH was 33% for Turner syndrome and 51% for nonsyndromic patients, with these numbers being too small for meaningful comparisons. There was a higher risk for cardiovascular disease events in patients with Turner syndrome vs male (aHR 3.72, 95% CI 1.64-8.39) and female comparators (aHR 4.55, 95% CI 1.87-11.06) excluding heart failure deaths., Conclusions: The 30-year transplant-free survival is similar for patients with Turner syndrome and nonsyndromic comparators with operated 2-ventricle LHOL without excess congenital heart disease risk. However, patients with Turner Syndrome still face increased cardiovascular disease morbidity, stressing the importance of lifelong comorbidity surveillance in this population., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Background: The status of the systemic right ventricular coronary microcirculation in hypoplastic left heart syndrome (HLHS) is largely unknown. It is presumed that the systemic right ventricle's coronary microcirculation exhibits unique pathophysiological characteristics of HLHS in Fontan circulation. The present study sought to quantify myocardial blood flow by cardiac magnetic resonance imaging and evaluate the determinants of microvascular coronary dysfunction and myocardial ischemia in HLHS., Methods: One hundred nineteen HLHS patients (median age, 4.80 years) and 34 healthy volunteers (median age, 5.50 years) underwent follow-up cardiac magnetic resonance imaging ≈1.8 years after total cavopulmonary connection. Right ventricle volumes and function, myocardial perfusion, diffuse fibrosis, and late gadolinium enhancement were assessed in 4 anatomic HLHS subtypes. Myocardial blood flow (MBF) was quantified at rest and during adenosine-induced hyperemia. Coronary conductance was estimated from MBF at rest and catheter-based measurements of mean aortic pressure (n=99)., Results: Hyperemic MBF in the systemic ventricle was lower in HLHS compared with controls (1.89±0.57 versus 2.70±0.84 mL/g per min; P <0.001), while MBF at rest normalized by the rate-pressure product, was similar (1.25±0.36 versus 1.19±0.33; P =0.446). Independent risk factors for a reduced hyperemic MBF were an HLHS subtype with mitral stenosis and aortic atresia ( P =0.017), late gadolinium enhancement ( P =0.042), right ventricular diastolic dysfunction ( P =0.005), and increasing age at total cavopulmonary connection ( P =0.022). The coronary conductance correlated negatively with systemic blood oxygen saturation (r, -0.29; P =0.02). The frequency of late gadolinium enhancement increased with age at total cavopulmonary connection ( P =0.014)., Conclusions: The coronary microcirculation of the systemic ventricle in young HLHS patients shows significant differences compared with controls. These hypothesis-generating findings on HLHS-specific risk factors for microvascular dysfunction suggest a potential benefit from early relief of frank cyanosis by total cavopulmonary connection.

Background: Early detection of right ventricular dysfunction after transannular patch for tetralogy of Fallot (TOF-TAP) is essential for management., Objectives: To evaluate echocardiographic metrics of ventricular function correlate with functional MRI measurements, in patients with TOF-TAP., Methods: A retrospective review of patients with TOF-TAP between 2007 and 2017 who had an echocardiogram and MRI within six months were analyzed. Systolic to diastolic ratio (SD ratio) was measured from the tricuspid regurgitation and adjusted for heart rate. Tricuspid Annular Plane Systolic Excursion (TAPSE), Fractional Area Change (FAC), and shortening fraction (SF) were additionally measured. Echocardiographic measurements were correlated with MRI assessment of right ventricular ejection fraction (RVEF), left ventricular ejection fraction (LVEF), right ventricular end-diastolic volume index (RVEDi), and right to left ventricle volume ratio (RV/LV)., Results: Of the 53 patients (mean age 12.8 years) that met inclusion criteria, 45 (85%) had available TR jets for SD ratio analysis. The HR adjusted SD ratio negatively correlated with RVEF (r = -.359, P = .016), LVEF (r = -.317, P = .038) and positively with RV/LV EDV ratio (r = .347, P = .024). TAPSE, FAC, and SF measurements did not show significant correlation., Conclusion: In patients with TOF-TAP, there is a moderate negative correlation between heart rate adjusted SD ratio and MRI metrics of ventricular function, suggesting that decreased filling time is a marker for reduced right ventricular function. The SD ratio may be a useful echocardiographic tool for serial evaluation of in this population., (© 2019 Wiley Periodicals, Inc.)

Despite major discoveries, traditional biomedical research has not always addressed topics perceived as priorities by patients and their families. Patient-centered care is predicated on research taking such priorities into account. The present study surveyed women with Turner syndrome (TS; 18+ years; n = 543), parents of women with TS (n = 232), and parents of younger daughters with TS (<18 years; n = 563), regarding their priorities for research. The study also included a quantitative audit of research categorized as either predominantly biomedical or psychological in the medical and other scientific literature. The overwhelming majority of all surveyed stakeholders (84% and higher) rated both biomedical and psychological research in TS as "very important," yet only approximately 9% of published research focused on psychological aspects of TS. The odds of women with TS identifying psychological research as "most important" was significantly lower (OR: 0.607; 95% CI: 0.375, 0.982] than the odds of parents making the same prioritization. Despite the majority of participants rating research as very important, only approximately half-rated participation in research as similarly important. The majority of respondents in all three groups (59%-73%) indicated they would "very likely" participate in research pertaining to eating or nutrition, quality of life, or genetic studies in TS. Substantially fewer expressed similar eagerness to participate in studies involving the study of a new medicine or medical device. Increased engagement of patient and family stakeholders in research requires that investigators select topics of study important to that community., (© 2019 Wiley Periodicals, Inc.)

To address knowledge gaps about Turner syndrome (TS) associated disease mechanisms, the Turner Syndrome Society of the United States created the Turner Syndrome Research Registry (TSRR), a patient-powered registry for girls and women with TS. More than 600 participants, parents or guardians completed a 33-item foundational survey that included questions about demographics, medical conditions, psychological conditions, sexuality, hormonal therapy, patient and provider knowledge about TS, and patient satisfaction. The TSRR platform is engineered to allow individuals living with rare conditions and investigators to work side-by-side. The purpose of this article is to introduce the concept, architecture, and currently available content of the TSRR, in anticipation of inviting proposals to utilize registry resources., (© 2019 Wiley Periodicals, Inc.)

Our goal is to identify the genetic underpinnings of bicuspid aortic valve and aortopathy in Turner syndrome. We performed whole exome sequencing on 188 Turner syndrome study subjects from the GenTAC registry. A gene-based burden test, SKAT-O, was used to evaluate the data using bicuspid aortic valve (BAV) and aortic dimension z-scores as covariates. This revealed that TIMP3 was associated with BAV and increased aortic dimensions at exome-wide significance. It had been previously shown that genes on chromosome Xp contribute to aortopathy when hemizygous. Our analysis of Xp genes revealed that hemizygosity for TIMP1, a functionally redundant paralogue of TIMP3, increased the odds of having BAV aortopathy compared to individuals with more than one TIMP1 copy. The combinatorial effect of a single copy of TIMP1 and TIMP3 risk alleles synergistically increased the risk for BAV aortopathy to nearly 13-fold. TIMP1 and TIMP3 are tissue inhibitors of matrix metalloproteinases (TIMPs) which are involved in development of the aortic valve and protection from thoracic aneurysms. We propose that the combination of TIMP1 haploinsufficiency and deleterious variants in TIMP3 significantly increases the risk of BAV aortopathy in Turner syndrome, and suggest that TIMP1 hemizygosity may play a role in euploid male aortic disease., (© 2019 Wiley Periodicals, Inc.)

Turner syndrome (TS), a genetic condition affecting roughly 1 in 2,000 females, is caused by a complete or partial loss of the second sex chromosome. This special issue of the American Journal of Medical Genetics Part C is a collection of research and clinical care reviews in TS from an international group of physician and scientist leaders who attended the 2018 "Turner Network Resource Symposium: Turner Science in the 21st Century", held in Arlington Virginia, July 15th-17th, 2018. Both this special issue and the 2018 Symposium are fueled by two rationales. First, inadequate attention has been given to health and psychosocial problems in girls and women with TS; and second, that an understanding of TS might shed light on the role of sex chromosome dosage in common conditions such as heart disease and autoimmune disease. These seminars interweave multiple themes: the fundamental partnership between participants with rare diseases and researchers, new knowledge regarding clinical care in TS, and an understanding of the "molecular phenotype" of TS-associated conditions., (Published 2019. This article is a U.S. Government work and is in the public domain in the USA.)

Cardiovascular imaging is essential to providing excellent clinical care for girls and women with Turner syndrome (TS). Congenital and acquired cardiovascular diseases are leading causes of the lifelong increased risk of premature death in TS. Non-invasive cardiovascular imaging is crucial for timely diagnosis and treatment planning, and a systematic and targeted imaging approach should combine echocardiography, cardiovascular magnetic resonance and, in select cases, cardiac CT. In recent decades, evidence has mounted for the need to perform cardiovascular imaging in all females with TS irrespective of karyotype and phenotype. This is due to the high incidence of outcome-determining lesions that often remain subclinical and occur in patterns specific to TS. This review provides an overview of state-of-the-art cardiovascular imaging practice in TS, by means of a review of the most recent literature, in the context of a recent consensus statement that has highlighted the role of cardiovascular diseases in these females., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2018. No commercial re-use. See rights and permissions. Published by BMJ.)

Turner syndrome is caused by complete or partial loss of the second sex chromosome, occurring in ~1 in 2,000 female births. There is a greatly increased incidence of aortopathy of unknown etiology, including bicuspid aortic valve (BAV), thoracic aortic aneurysms, aortic dissection and rupture. We performed whole exome sequencing on 188 Turner syndrome participants from the National Registry of Genetically Triggered Thoracic Aortic Aneurysms and Cardiovascular Related Conditions (GenTAC). A gene-based burden test, the optimal sequence kernel association test (SKAT-O), was used to evaluate the data with BAV and aortic dimension z-scores as covariates. Genes on chromosome Xp were analyzed for the potential to contribute to aortopathy when hemizygous. Exome analysis revealed that TIMP3 was associated with indices of aortopathy at exome-wide significance (p = 2.27 x 10(-7)), which was replicated in a separate cohort. The analysis of Xp genes revealed that TIMP1, which is a functionally redundant paralogue of TIMP3, was hemizygous in >50% of our discovery cohort and that having only one copy of TIMP1 increased the odds of having aortopathy (OR = 9.76, 95% CI = 1.91-178.80, p = 0.029). The combinatorial effect of a single copy of TIMP1 and TIMP3 risk alleles further increased the risk for aortopathy (OR = 12.86, 95% CI = 2.57-99.39, p = 0.004). The products of genes encoding tissue inhibitors of matrix metalloproteinases (TIMPs) are involved in development of the aortic valve and protect tissue integrity of the aorta. We propose that the combination of X chromosome TIMP1 hemizygosity and variants of its autosomal paralogue TIMP3, significantly increases the risk of aortopathy in Turner syndrome., Competing Interests: The authors have declared that no competing interests exist.

Girls and women with Turner syndrome face a lifelong struggle with both congenital heart disease and acquired cardiovascular conditions. Bicuspid aortic valve is common, and many have left-sided heart obstructive disease of varying severity, from hypoplastic left-sided heart syndrome to minimal aortic stenosis or coarctation of the aorta. Significant enlargement of the thoracic aorta may progress to catastrophic aortic dissection and rupture. It is becoming increasingly apparent that a variety of other cardiovascular conditions, including early-onset hypertension, ischemic heart disease, and stroke, are the major factors reducing the life span of those with Turner syndrome. The presentations and management of cardiovascular conditions in Turner syndrome differ significantly from the general population. Therefore, an international working group reviewed the available evidence regarding the diagnosis and treatment of cardiovascular diseases in Turner syndrome. It is recognized that the suggestions for clinical practice stated here are only the beginning of a process that must also involve the establishment of quality indicators, structures and processes for implementation, and outcome studies.

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., (© 2017 Wiley Periodicals, Inc.)

Turner syndrome affects 25-50 per 100,000 females and can involve multiple organs through all stages of life, necessitating multidisciplinary approach to care. Previous guidelines have highlighted this, but numerous important advances have been noted recently. These advances cover all specialty fields involved in the care of girls and women with TS. This paper is based on an international effort that started with exploratory meetings in 2014 in both Europe and the USA, and culminated with a Consensus Meeting held in Cincinnati, Ohio, USA in July 2016. Prior to this meeting, five groups each addressed important areas in TS care: 1) diagnostic and genetic issues, 2) growth and development during childhood and adolescence, 3) congenital and acquired cardiovascular disease, 4) transition and adult care, and 5) other comorbidities and neurocognitive issues. These groups produced proposals for the present guidelines. Additionally, four pertinent questions were submitted for formal GRADE (Grading of Recommendations, Assessment, Development and Evaluation) evaluation with a separate systematic review of the literature. These four questions related to the efficacy and most optimal treatment of short stature, infertility, hypertension, and hormonal replacement therapy. The guidelines project was initiated by the European Society for Endocrinology and the Pediatric Endocrine Society, in collaboration with The European Society for Pediatric Endocrinology, The Endocrine Society, European Society of Human Reproduction and Embryology, The American Heart Association, The Society for Endocrinology, and the European Society of Cardiology. The guideline has been formally endorsed by the European Society for Endocrinology, the Pediatric Endocrine Society, the European Society for Pediatric Endocrinology, the European Society of Human Reproduction and Embryology and the Endocrine Society. Advocacy groups appointed representatives who participated in pre-meeting discussions and in the consensus meeting., (© 2017 European Society of Endocrinology.)

Marfan syndrome (MFS) is an autosomal dominant connective tissue disease associated with acute aortic dissection (AAD). We used 2 large registries that include patients with MFS to investigate possible trends in the chronobiology of AAD in MFS. We queried the International Registry of Acute Aortic Dissection (IRAD) and the Genetically Triggered Thoracic Aortic Aneurysms and Cardiovascular Conditions (GenTAC) registry to extract data on all patients with MFS who had suffered an AAD. The group included 257 patients with MFS who suffered an AAD from 1980 to 2012. The chi-square tests were used for statistical testing. Mean subject age at time of AAD was 38 years, and 61% of subjects were men. AAD was more likely in the winter/spring season (November to April) than the other half of the year (57% vs 43%, p = 0.05). Dissections were significantly more likely to occur during the daytime hours, with 65% of dissections occurring from 6 a.m. to 6 p.m. (p = 0.001). Men were more likely to dissect during the daytime hours (6 a.m. to 6 p.m.) than women (74% vs 51%, p = 0.01). These insights offer a glimpse of the times of greatest vulnerability for patients with MFS who suffer from this catastrophic event. In conclusion, the chronobiology of AAD in MFS reflects that of AAD in the general population., (Copyright © 2016 Elsevier Inc. All rights reserved.)

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., (© 2016 Wiley Periodicals, Inc.)

Background: The risk of aortic complications associated with pregnancy in women with Marfan syndrome (MFS) is not fully understood., Methods and Results: MFS women participating in the large National Registry of Genetically Triggered Thoracic Aortic Aneurysms and Cardiovascular Conditions (GenTAC) were evaluated. Among 184 women with MFS in whom pregnancy information was available, 94 (51%) had a total of 227 pregnancies. Among the women with pregnancies, 10 (10.6%) experienced a pregnancy-related aortic complication (4 type A and 3 type B dissections, 1 coronary artery dissection, and 2 with significant [≥3 mm] aortic growth). Five of 7 aortic dissections, including all 3 type B, and the coronary dissection (75% of all dissections) occurred in the postpartum period. Only 5 of 8 women with pregnancy-associated dissection were aware of their MFS diagnosis. The rate of aortic dissection was higher during the pregnancy and postpartum period (5.4 per 100 person-years vs 0.6 per 100 person-years of nonpregnancy; rate ratio, 8.4 [95% CI=3.9, 18.4]; P<0.0001)., Conclusions: Pregnancy in MFS is associated with an increased risk of aortic dissection, both types A and B, particularly in the immediate postpartum period. Lack of knowledge of underlying MFS diagnosis before aortic dissection is a major contributing factor. These findings underscore the need for early diagnosis, prepregnancy risk counseling, and multidisciplinary peripartum management., (© 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.)

Cardiovascular disease is the major factor that reduces lifespan in Turner syndrome. High blood pressure (BP) is common in Turner syndrome and is the most easily treatable cardiovascular risk factor. We studied the prevalence of elevated screening systemic BP, awareness of the problem, and its clinical associations in a large group of girls attending the annual meeting of the Turner Syndrome Society of the United States. Among 168 girls aged 2 to 17 years, 42% had elevated screening BP (systolic and diastolic), yet only 8% reported a previous diagnosis of hypertension. History of aortic coarctation repair (17%) was positively associated with elevated systolic BP (52% versus 32%; P<0.05). Elevated systolic BP was positively associated with obesity (56% versus 31%; P<0.05). Because the prevalence of obesity in the studied population was similar to Center for Disease Control published data for obesity in all girls and the prevalence of increased BP is approximately twice that of the general population, the Turner syndrome phenotype/genotype probably includes an intrinsic risk for hypertension. Obesity and repaired aortic coarctation increase this risk further. There seems to be a BP awareness gap in girls with Turner syndrome. Because girls living with Turner syndrome are a sensitized population for hypertension, further study may provide clues to genetic factors leading to a better understanding of essential hypertension in the general population., (© 2016 American Heart Association, Inc.)

Objectives: This study sought to evaluate variability in aortic measurements with multiple imaging modalities in clinical centers by comparing with a standardized measuring protocol implemented in a core laboratory., Background: In patients with aortic disease, imaging of thoracic aorta plays a major role in risk stratifying individuals for life-threatening complications and in determining timing of surgical intervention. However, standardization of the procedures for performance of aortic measurements is lacking., Methods: To characterize the diversity of methods used in clinical practice, we compared aortic measurements performed by echocardiography, computed tomography (CT), and magnetic resonance imaging (MRI) at the 6 GenTAC (National Registry of Genetically Triggered Thoracic Aortic Aneurysms and Cardiovascular Conditions) clinical centers to those performed at the imaging core laboratory in 965 studies. Each center acquired and analyzed their images according to local protocols. The same images were subsequently analyzed blindly by the core laboratory, on the basis of a standardized protocol for all imaging modalities. Paired measurements from clinical centers and core laboratory were compared by mean of differences and intraclass correlation coefficient (ICC)., Results: For all segments of the ascending aorta, echocardiography showed a higher ICC (0.84 to 0.93) than CT (0.84) and MRI (0.82 to 0.90), with smaller mean of differences. MRI showed higher ICC for the arch and descending aorta (0.91 and 0.93). In a mixed adjusted model, the different imaging modalities and clinical centers were identified as sources of variability between clinical and core laboratory measurements, whereas age groups or diagnosis at enrollment were not., Conclusions: By comparing core laboratory with measurements from clinical centers, our study identified important sources of variability in aortic measurements. Furthermore, our findings with regard to CT and MRI suggest a need for imaging societies to work toward the development of unifying acquisition protocols and common measuring methods., (Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

In Turner syndrome, linear growth is less than the general population. Consequently, to assess stature in Turner syndrome, condition-specific comparators have been employed. Similar reference curves for cardiac structures in Turner syndrome are currently unavailable. Accurate assessment of the aorta is particularly critical in Turner syndrome because aortic dissection and rupture occur more frequently than in the general population. Furthermore, comparisons to references calculated from the taller general population with the shorter Turner syndrome population can lead to over-estimation of aortic size causing stigmatization, medicalization, and potentially over-treatment. We used echocardiography to measure aortic diameters at eight levels of the thoracic aorta in 481 healthy girls and women with Turner syndrome who ranged in age from two to seventy years. Univariate and multivariate linear regression analyses were performed to assess the influence of karyotype, age, body mass index, bicuspid aortic valve, blood pressure, history of renal disease, thyroid disease, or growth hormone therapy. Because only bicuspid aortic valve was found to independently affect aortic size, subjects with bicuspid aortic valve were excluded from the analysis. Regression equations for aortic diameters were calculated and Z-scores corresponding to 1, 2, and 3 standard deviations from the mean were plotted against body surface area. The information presented here will allow clinicians and other caregivers to calculate aortic Z-scores using a Turner-based reference population. © 2015 Wiley Periodicals, Inc., (© 2015 Wiley Periodicals, Inc.)

Background: Heterozygous human NKX2-5 homeodomain (DNA-binding domain) missense mutations are highly penetrant for varied congenital heart defects, including progressive atrioventricular (AV) block requiring pacemaker implantation. We recently replicated this genetic defect in a murine knockin model, in which we demonstrated highly penetrant, pleiotropic cardiac anomalies. In this study, we examined postnatal AV conduction in the knockin mice., Methods and Results: A murine knockin model (Arg52Gly, Nkx2-5(+/R52G)) in a 129/Sv background was analyzed by histopathology, surface, and telemetry ECG, and in vivo electrophysiology studies, comparing with control Nkx2-5(+/+) mice at diverse postnatal stages, ranging from postnatal day 1 (P1) to 17 months. PR prolongation (first degree AV block) was present at 4 weeks, 7 months, and 17 months of age, but not at P1 in the mutant mice. Advanced AV block was also occasionally demonstrated in the mutant mice. Electrophysiology studies showed that AV nodal function and right ventricular effective refractory period were impaired in the mutant mice, whereas sinus nodal function was not affected. AV nodal size was significantly smaller in the mutant mice than their controls at 4 weeks of age, corresponding to the presence of PR prolongation, but not P1, suggesting, at least in part, that the conduction abnormalities are the result of a morphologically atrophic AV node., Conclusions: The highly penetrant and progressive AV block phenotype seen in human heterozygous missense mutations in NKX2-5 homeodomain was replicated in mice by knocking in a comparable missense mutation., (© 2015 American Heart Association, Inc.)

Objective: To quantify myocardial blood flow in infants and children with mild or moderate aortic stenosis using adenosine-infusion cardiac magnetic resonance., Background: It is unclear whether asymptomatic children with mild/moderate aortic stenosis have myocardial abnormalities. In addition, cardiac magnetic resonance-determined normative myocardial blood flow data in children have not been reported., Methods: We studied 31 infants and children with either haemodynamically normal hearts (n=20, controls) or mild/moderate aortic stenosis (n=11). The left ventricular myocardium was divided into six segments, and the change in average segmental signal intensity during contrast transit was used to quantify absolute flow (ml/g/minute) at rest and during adenosine infusion by deconvolution of the tissue curves with the arterial input of contrast., Results: In all the cases, adenosine was well tolerated without complications. The mean pressure gradient between the left ventricle and the ascending aorta was higher in the aortic stenosis group compared with controls (24 versus 3 mmHg, p<0.001). Left ventricular wall mass was slightly higher in the aortic stenosis group compared with controls (65 versus 50 g/m², p<0.05). After adenosine treatment, both the absolute increase in myocardial blood flow (p<0.0001) and the hyperaemic flow significantly decreased (p<0.001) in children with mild/moderate aortic stenosis compared with controls., Conclusion: Abnormal myocardial blood flow in children with mild/moderate aortic stenosis may be an important therapeutic target.

Turner syndrome, a congenital condition that affects ∼1/2,500 births, results from absence or structural alteration of the second sex chromosome. There has been substantial effort by numerous clinical and genetic research groups to delineate the clinical, pathophysiological, cytogenetic, and molecular features of this multisystem condition. Questions about the molecular-genetic and biological basis of many of the clinical features remain unanswered, and health care providers and families seek improved care for affected individuals. The inaugural "Turner Resource Network (TRN) Symposium" brought together individuals with Turner syndrome and their families, advocacy group leaders, clinicians, basic scientists, physician-scientists, trainees and other stakeholders with interest in the well-being of individuals and families living with the condition. The goal of this symposium was to establish a structure for a TRN that will be a patient-powered organization involving those living with Turner syndrome, their families, clinicians, and scientists. The TRN will identify basic and clinical questions that might be answered with registries, clinical trials, or through bench research to promote and advocate for best practices and improved care for individuals with Turner syndrome. The symposium concluded with the consensus that two rationales justify the creation of a TRN: inadequate attention has been paid to the health and psychosocial issues facing girls and women who live with Turner syndrome; investigations into the susceptibility to common disorders such as cardiovascular or autoimmune diseases caused by sex chromosome deficiencies will increase understanding of disease susceptibilities in the general population., (© 2015 Wiley Periodicals, Inc.)

Purpose: Turner syndrome is a developmental disorder caused by partial or complete monosomy for the X chromosome in 1 in 2,500 females. We hypothesized that single-nucleotide polymorphism (SNP) array genotyping could provide superior resolution in comparison to metaphase karyotype analysis to facilitate genotype-phenotype correlations., Methods: We genotyped 187 Turner syndrome patients with 733,000 SNP marker arrays. All cases met diagnostic criteria for Turner syndrome based on karyotypes (60%) or characteristic physical features. The SNP array results confirmed the diagnosis of Turner syndrome in 100% of cases., Results: We identified a single X chromosome (45,X) in 113 cases. In 58 additional cases (31%), other mosaic cell lines were present, including isochromosomes (16%), rings (5%), and Xp deletions (8%). The remaining cases were mosaic for monosomy X and normal male or female cell lines. Array-based models of X chromosome structure were compatible with karyotypes in 104 of 116 comparable cases (90%). We found that the SNP array data did not detect X-autosome translocations (three cases) but did identify two derivative Y chromosomes and 13 large copy-number variants that were not detected by karyotyping., Conclusion: Our study is the first systematic comparison between the two methods and supports the utility of SNP array genotyping to address clinical and research questions in Turner syndrome.

Primary vascular tumours of the heart are rare and heterogeneous in their presentation and classification.We present a primary intramuscular vascular malformation of the left ventricle in an asymptomatic 12-year-old girl. Characteristics on cardiac magnetic resonance imaging, specifically increased signal intensity on T2-weighted images, and marked contrast enhancement with gadolinium were suggestive of increased vascularity. Histologically, the mass was determined to be an intramuscular vascular malformation of the small vessel arteriovenous subtype. This represents one of a select few intramuscular vascular malformations of the left ventricle reported in children. Our patient remains completely asymptomatic and has had no change in the size and appearance of the mass after more than 30 months of follow-up.

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., (Copyright © 2013 Wiley Periodicals, Inc.)

Background: Girls and women with Turner syndrome are at risk for aortic dissection and rupture. However, the size of the aorta and the clinical characteristics among those with Turner syndrome and dissection have received little attention., Methods and Results: We obtained medical records from 20 individuals who voluntarily participated in the International Turner Syndrome Aortic Dissection Registry. Type A dissections occurred in 17 of 20 (85%) cases, and type B occurred in 3 cases of which 1 occurred after coarctation stent placement. Of those with spontaneous aortic dissections, 18 of 19 (95%) had an associated cardiac malformation that included a bicuspid aortic valve. In 1 individual there was no predisposing finding other than the presence of Turner syndrome. Associated pregnancy was documented in 1 of 19 (5%). More than half (13/19, 68%) came to medical attention >24 hours after the onset of symptoms. For those with type A dissections, the mean ascending aortic size index was 2.7±0.6 cm/m(2) (n=9)., Conclusions: Aortic dissection in Turner syndrome occurs in young individuals at smaller aortic diameters than in the general population or other forms of genetically triggered aortopathy. The absence of aortic valve or other cardiac malformations appears to markedly reduce the risk of aortic dissection However, aortic dissection can occur in Turner syndrome without cardiac malformations or hypertension. Individuals with Turner syndrome who are >18 years of age with an ascending aortic size index >2.5 cm/m(2) should be considered for an aortic operation to prevent aortic dissection.

Cardiac malformations occur commonly in Turner syndrome (TS), but the outcomes of cardiac operations and catheter-based procedures are unknown. The Pediatric Cardiac Care Consortium database was queried for individuals with TS and other female subjects without genetic abnormalities or syndromes (non-TS [NTS]). Procedures for left-sided heart lesions represented most TS procedures (95.2%). Three hundred ninety-eight patients with TS who underwent 637 of these procedures of interest were compared with 25,913 female NTS subjects who underwent 56,625 procedures. The numbers of procedures per admission (1.47 vs 1.61, p = 0.01) and per patient (1.85 vs 2.16, p <0.0001) were significantly lower in patients with TS. Procedures for cyanotic heart disease other than hypoplastic left heart (HLH) were performed 4.5-fold less frequently in patients with TS. Patients with TS and NTS subjects had equivalent hospital lengths of stay, except for patients with TS who underwent hypoplastic aortic arch operations, patent ductus arteriosus ligation, pulmonary artery balloon dilation, balloon atrial septostomy, and catheter closure of atrial septal defects. There were 34 deaths among patients with TS and 1,795 among NTS subjects (8.6% vs 7.2%, p = 0.30). When HLH was excluded, mortality was lower in the TS group (3.9% vs 6.5%, p = 0.05). Operations for partial anomalous pulmonary venous connection (14.3% vs 1.9%, p = 0.03) and HLH (90.4% vs 70.5%, p = 0.08) were more likely to result in death in patients with TS. In conclusion, given generally comparable lengths of stay and numbers of procedures as well as uniformly excellent results, these data suggest that the diagnosis of TS does not increase the utilization of limited health care resources. Operations for HLH and partial anomalous pulmonary vein connection carry additional risk for those with TS. These results will permit risk stratification, prognostication, and counseling of individuals with TS and their families., (Copyright © 2012. Published by Elsevier Inc.)

Cardiovascular abnormalities are important features of Costello syndrome and other Ras/MAPK pathway syndromes ("RASopathies"). We conducted clinical, pathological and molecular analyses of 146 patients with an HRAS mutation including 61 enrolled in an ongoing longitudinal study and 85 from the literature. In our study, the most common (84%) HRAS mutation was p.G12S. A congenital heart defect (CHD) was present in 27 of 61 patients (44%), usually non-progressive valvar pulmonary stenosis. Hypertrophic cardiomyopathy (HCM), typically subaortic septal hypertrophy, was noted in 37 (61%), and 5 also had a CHD (14% of those with HCM). HCM was chronic or progressive in 14 (37%), stabilized in 10 (27%), and resolved in 5 (15%) patients with HCM; follow-up data was not available in 8 (22%). Atrial tachycardia occurred in 29 (48%). Valvar pulmonary stenosis rarely progressed and atrial septal defect was uncommon. Among those with HCM, the likelihood of progressing or remaining stable was similar (37%, 41% respectively). The observation of myocardial fiber disarray in 7 of 10 (70%) genotyped specimens with Costello syndrome is consistent with sarcomeric dysfunction. Multifocal atrial tachycardia may be distinctive for Costello syndrome. Potentially serious atrial tachycardia may present in the fetus, and may continue or worsen in about one-fourth of those with arrhythmia, but is generally self-limited in the remaining three-fourths of patients. Physicians should be aware of the potential for rapid development of severe HCM in infants with Costello syndrome, and the need for cardiovascular surveillance into adulthood as the natural history continues to be delineated., (Copyright © 2011 Wiley-Liss, Inc.)

Objectives: The purpose of this study was to assess the ability of plasma B-type natriuretic peptide (BNP) to diagnose significant cardiovascular disease (CVD) in the pediatric population., Background: BNP has been shown to be reliable in detecting ventricular dysfunction and heart failure in adults. Timely and accurate identification of significant pediatric heart disease is important but challenging. A simple blood test could aid the front-line physician in this task., Methods: Subjects without a history of heart disease with findings possibly attributable to significant CVD in the acute care setting requiring a cardiology consult were enrolled. Clinicians were blinded to the BNP result, and confirmation of disease was made by cardiology consultation., Results: Subjects were divided into a neonatal (n = 42, 0 to 7 days) and older age group (n = 58, >7 days to 19 years). CVD was present in 74% of neonates and 53% of the older age group. In neonates with disease, median BNP was 526 pg/ml versus 96 pg/ml (p < 0.001) for those without disease. In older children with disease, median BNP was 122 pg/ml versus 22 pg/ml in those without disease (p < 0.001). Subjects with disease from an anatomic defect, a longer hospital stay, or who died had higher BNP. A BNP of 170 pg/ml yielded a sensitivity of 94% and specificity of 73% in the neonatal group and 87% and 70% in the older age group, respectively, using a BNP of 41 pg/ml., Conclusions: BNP is a reliable test to diagnose significant structural or functional CVD in children. Optimal cutoff values are different from adult values.

Patients with Turner syndrome (TS) are at risk for aortic dissection, but the clinical profile for those at risk is not well described. In addition to reporting two new cases, we performed an electronic search to identify all reported cases of aortic dissection associated with TS. In total, 85 cases of aortic dissection in TS were reported between 1961 and 2006. Dissection occurred at a young age, 30.7 (range 4-64) years, which is significantly earlier than its occurrence in the general female population (68 years). Importantly, in 11% of the cases, neither hypertension nor congenital heart disease were identified, suggesting that TS alone is an independent risk factor for aortic dissection; however, the cases where no risk factors were identified were very poorly documented. A TS aortic dissection registry has been established to determine the natural history and risk factors better (http://www.turnersyndrome.org/).

Objective: Because aortic dilation increases the risk for dissection in the general adult population, and dissection occurs with greater frequency at a young age with Turner syndrome, we studied the prevalence, magnitude, and determinants of aortic dilation in a large group of girls and young women with Turner syndrome., Patients and Methods: Participants at annual Turner syndrome society meetings completed a questionnaire regarding their medical history. Echocardiographic measurements of their aorta were converted to z scores by using data from a larger group of normal control female subjects. Bivariable and multivariable analyses evaluated the effects of Turner syndrome features, such as a bicuspid aortic valve, coarctation, growth-hormone therapy, blood pressure, and karyotype, on aortic size., Results: Among 138 individuals with Turner syndrome <18 years old, 49% had the 45,X karyotype, 26% had bicuspid aortic valve, 17% had a history of coarctation, 78% had a history of growth-hormone therapy, and 40% had hypertension. Aortic z scores were calculated by using data from 407 control subjects. Bivariable analyses revealed that a bicuspid aortic valve, growth hormone, and 45,X karyotype predicted a larger proximal aorta at >/=1 level. Multivariable analysis predicted a larger proximal aorta at all of the levels only for bicuspid aortic valve individuals and at the annular level for those who received growth hormone. Importantly, all of the analyses revealed that Turner syndrome predicted a larger proximal aorta independent of these characteristics., Conclusions: Among young individuals with Turner syndrome, a bicuspid aortic valve predicts a larger proximal aorta, and growth-hormone use may predict a larger aortic annulus. Compared with a control population, Turner syndrome alone is an independent risk factor for aortic dilation.

Girls and women with Turner syndrome are at risk for catastrophic aortic dissection and rupture, but the clinical profile for those at risk is not well described. In addition to reporting two new cases, we performed an electronic search to identify all reported cases of aortic dissection associated with Turner syndrome. Particular attention was paid to the reporting of systemic hypertension (HTN) and congenital heart disease (CHD) which are known risk factors for aortic disease in the general population. In total, 85 cases of aortic dissection in TS were reported between 1961 and 2006. Dissection occurred at a young age, 30.7 (range 4-64) years, which is significantly earlier than its occurrence in the general female population (68 years). Of the cases for which HTN and CHD were explicitly assessed, 15% had HTN alone, 30% had CHD alone and 34% had both. Importantly, in 11% of the cases, neither HTN nor CHD were identified, suggesting that TS alone is an independent risk factor for aortic dissection; however, the cases where no risk factors were identified were very poorly documented. Dissection in women with TS undergoing assisted reproductive techniques (ART) frequently resulted in death. The literature on aortic dissection in TS is sparse and most cases are poorly documented, making it difficult to establish firm guidelines regarding monitoring and treatment. A TS aortic dissection registry has been established to better determine the natural history and risk factors (http://www.tssus.org/readweb.asp?wid = 3092).

Objectives: We tested a newly developed 4-dimensional (4D) right ventricular (RV) analysis method for computing RV volumes for both 3-dimensional (3D) ultrasound (US) and magnetic resonance (MR) images., Background: Asymmetry and the anatomical complexity of the RV make accurate determination of RV shape and volume difficult., Methods: Thirty patients, 14 with grossly normal cardiac anatomy and 16 with major congenital heart disease, were studied at the same visit with both 3D echocardiography (echo) and magnetic resonance imaging (MRI) for RV size and function. Ultrasound images were acquired on a Philips 7500 system (Philips Medical Systems, Andover, Massachusetts) with a matrix-array transducer (real-time 3D echo) with full volume sweeps from apical and subcostal views. Sagittal, 4-chamber, and coronal views were derived for contour detection (all 12 to 24 slices). The MR images were acquired with a 3-T MRI magnet with segmented cine-loop gradient echo sequences in short- and rotated long-axis views to cover the RV inflow, body, and outflow tract. The RV volumes were analyzed with the new software applicable to 3D echo MR images., Results: New software aided delineation of the RV free wall, tricuspid valve, RV outflow tract, and apex on 3D echo volumes. Although there was a slightly higher variability measuring right ventricular ejection fraction (RVEF) and volumes obtained by US compared with MRI, both imaging methods showed closely correlated results. The RVEF was measured with 4% variability for US and 5% variability for MRI with a correlation coefficient of r = 0.91. The RV end-diastolic volume was measured at 70.97 +/- 15.0 ml with 3D US and at 70.06 +/- 14.8 ml with MRI (r = 0.99), end-systolic volume measured 39.8 +/- 10.4 ml with 3D US and 39.1 +/- 10.2 ml with MRI (r = 0.98)., Conclusions: The new RV analysis software allowed validation of the accuracy of 4D echo RV volume data compared with MRI.