Physical fitness in children with Marfan and Loeys-Dietz syndrome: associations between cardiovascular parameters, systemic manifestations, fatigue, and pain.

Children with Marfan (MFS) and Loeys-Dietz syndrome (LDS) report limitations in physical activities, sports, school, leisure, and work participation in daily life. This observational, cross-sectional, multicenter study explores associations between physical fitness and cardiovascular parameters, systemic manifestations, fatigue, and pain in children with MFS and LDS. Forty-two participants, aged 6-18 years (mean (SD) 11.5(3.7)), diagnosed with MFS (n = 36) or LDS (n = 6), were enrolled. Physical fitness was evaluated using the Fitkids Treadmill Test's time to exhaustion (TTE) outcome measure. Cardiovascular parameters (e.g., echocardiographic parameters, aortic surgery, cardiovascular medication) and systemic manifestations (systemic score of the revised Ghent criteria) were collected. Pain was obtained by visual analog scale. Fatigue was evaluated by PROMIS® Fatigue-10a-Pediatric-v2.0-short-form and PROMIS® Fatigue-10a-Parent-Proxy-v2.0-short-form. Multivariate linear regression analyses explored associations between physical fitness (dependent variable) and independent variables that emerged from the univariate linear regression analyses (criterion p < .05). The total group (MFS and LDS) and the MFS subgroup scored below norms on physical fitness TTE Z-score (mean (SD) -3.1 (2.9); -3.0 (3.0), respectively). Univariate analyses showed associations between TTE Z-score aortic surgery, fatigue, and pain (criterion p < .05). Multivariate analyses showed an association between physical fitness and pediatric self-reported fatigue that explained 48%; 49%, respectively, of TTE Z-score variance (F (1,18) = 18.6, p ≤ .001, r2 = .48; F (1,15) = 16,3, p = .01, r2 = .49, respectively).    Conclusions: Physical fitness is low in children with MFS or LDS and associated with self-reported fatigue. Our findings emphasize the potential of standardized and tailored exercise programs to improve physical fitness and reduce fatigue, ultimately enhancing the physical activity and sports, school, leisure, and work participation of children with MFS and LDS. What is Known: • Marfan and Loeys-Dietz syndrome are heritable connective tissue disorders and share cardiovascular and systemic manifestations. • Children with Marfan and Loeys-Dietz syndrome report increased levels of disability, fatigue and pain, as well as reduced levels of physical activity, overall health and health-related quality of life. What is New: • Physical fitness is low in children with Marfan and Loeys-Dietz syndrome and associated with self-reported fatigue. • Our findings emphasize the potential of standardized and tailored exercise programs to improve physical fitness and reduce fatigue, ultimately enhancing the physical activity and sports, school, leisure, and work participation of children with Marfan and Loeys-Dietz syndrome.

Mitral Valve Prolapse and Its Motley Crew-Syndromic Prevalence, Pathophysiology, and Progression of a Common Heart Condition.

Mitral valve prolapse (MVP) is a commonly occurring heart condition defined by enlargement and superior displacement of the mitral valve leaflet(s) during systole. Although commonly seen as a standalone disorder, MVP has also been described in case reports and small studies of patients with various genetic syndromes. In this review, we analyzed the prevalence of MVP within syndromes where an association to MVP has previously been reported. We further discussed the shared biological pathways that cause MVP in these syndromes, as well as how MVP in turn causes a diverse array of cardiac and noncardiac complications. We found 105 studies that identified patients with mitral valve anomalies within 18 different genetic, developmental, and connective tissue diseases. We show that some disorders previously believed to have an increased prevalence of MVP, including osteogenesis imperfecta, fragile X syndrome, Down syndrome, and Pseudoxanthoma elasticum, have few to no studies that use up-to-date diagnostic criteria for the disease and therefore may be overestimating the prevalence of MVP within the syndrome. Additionally, we highlight that in contrast to early studies describing MVP as a benign entity, the clinical course experienced by patients can be heterogeneous and may cause significant cardiovascular morbidity and mortality. Currently only surgical correction of MVP is curative, but it is reserved for severe cases in which irreversible complications of MVP may already be established; therefore, a review of clinical guidelines to allow for earlier surgical intervention may be warranted to lower cardiovascular risk in patients with MVP.

Homozygous deletion of exons 2-7 within TGFB3 gene in a child with severe Loeys-Dietz syndrome and Marfan-like features.

We describe a patient with palatal abnormalities-cleft palate and bifid uvula; distinctive facial features-long and triangular face, large ears and nose, thin lips and dental crowding; musculoskeletal abnormalities-severe scoliosis, joint laxity, long digits, flat feet, decreased muscle mass, and diminished muscle strength; and cardiac features-a dilatated ascending aorta at the level of Valsalva sinuses and a patent foramen ovale. Sequence analysis and deletion/duplication testing for a panel of genes involved in connective tissue disorders revealed the presence of a novel homozygous deletion of exons 2-7 in TGFB3 gene. Heterozygous pathogenic mutations in TGFB3 have been associated with Loeys-Dietz syndrome 5 (LDS5) and Arrhythmogenic Right Ventricular Dysplasia type 1. Here, we report the first case of a homozygous TGFB3 variant associated with a severe LDS5 and Marfan-like presentation.

Neurovascular findings in children and young adults with Loeys-Dietz syndromes: Informing recommendations for screening.

INTRODUCTION: Loeys-Dietz Syndromes (LDS) are a group of connective tissue disorders associated with vascular abnormalities, including arterial tortuosity, aneurysms, and dissections. While neurovascular involvement is common, no pediatric or young adult recommendations for screening exist. We aimed to review our institution's experience with special focus on neurovascular imaging to better understand the pathology and guide screening. METHODS: A retrospective cohort study of patients with LDS was performed. Demographics, genetic subtype, clinical and radiographical data were analyzed. Primary outcome measures included pathology on neurovascular imaging, time to progression, and arterial tortuosity indexes for bilateral cervical internal carotid arteries (ICA) and vertebral arteries (VA). RESULTS: Of 47 patients with LDS identified, 39 (83.0%) were found to have neuroimaging. Intracranial and cervical vascular tortuosity were seen in 79.5% and 64.1%, respectively. Twenty-one patients (44.7%) received follow-up screening, of which 3 were found to have progression. Time to progression was an average of 2.1 years. Average follow-up was 607 days (range 123-3070 days). Mean Arterial Tortuosity Index for the right ICA, left ICA, right VA, and left VA were 18, 20, 49, and 47, respectively. Comparison of interval percent change in Arterial Tortuosity Index over the course of follow-up demonstrated small changes in the right ICA (mean 5%), left ICA (mean 1%), right VA (mean 1%), and left VA (mean 2%). CONCLUSIONS: Arterial tortuosity was most prevalent, though it did not progress significantly over time. We suggest an algorithm for management and serial screening to guide management of pediatric and young adults with LDS.

Valve-sparing aortic root replacement in children: Outcomes from 100 consecutive cases.

OBJECTIVE: Valve-sparing root replacement is an attractive alternative to composite mechanical or biologic prostheses for aortic root aneurysms in children. Data on outcomes in pediatric patients are limited. We present our institutional experience with 100 consecutive pediatric valve-sparing aortic root procedures. METHODS: All children who underwent valve-sparing root replacement at our institution from May 1997 to August 2017 were identified, and echocardiographic and clinical data were reviewed. The primary end point was mortality, and secondary end points included complications, further interventions, and subsequent valvular dysfunction. RESULTS: Median age at operation was 13.6 years (interquartile range, 9.42-15.9); 51 patients (51%) had Marfan syndrome, and 39 patients (39%) had Loeys-Dietz syndrome. Mean preoperative maximum sinus diameter was 4.4 ± 0.71 cm (z score 7.3 [5.7-9.3]). Most patients (n = 80, 80%) underwent reimplantation procedures with a Valsalva graft. Four patients (4%) underwent David I reimplantation with a straight-tube graft, 13 patients (13%) underwent a Yacoub remodeling procedure, and 3 patients (3%) underwent a Florida sleeve procedure. Perioperative valve-sparing root replacement mortality was 2% (n = 2). Six patients required late reintervention for development of pseudoaneurysms. Eight patients underwent additional aortic surgery. Average time to reoperation was 7.23 ± 4.56 years. Of the 84 patients undergoing a reimplantation procedure, 5 (5.9%) underwent late valve replacement versus 5 (33.3%) of the 15 patients who received a remodeling procedure (P = .001). CONCLUSIONS: Valve-sparing root replacement is a safe and effective option for children with aortic root aneurysms in children. The reimplantation procedure is preferred. Late aortic insufficiency and pseudoaneurysm formation remain late concerns.

Systematic review of quality of life in persons with hereditary thoracic aortic aneurysm and dissection diagnoses.

The purpose of this study was to explore the literature on quality of life (QoL) in patients with hereditary thoracic aortic aneurysm and dissection (HTAAD); including Marfan syndrome (MFS), Loeys-Dietz syndrome (LDS), vascular Ehlers-Danlos syndrome (vEDS) and other HTAAD diagnoses, critically appraising and synthesizing the relevant literature. A systematic review was performed by searching the published literature using available medical, physical, psychological, social databases and other sources. Studies addressing QoL in persons with an HTAAD diagnosis, published in peer-reviewed journals were assessed. Of 227 search results, 20 articles satisfied the eligibility criteria. No studies of QoL in LDS, vEDS, or other HTAAD were found, only on MFS. Most studies had been published in the last 3 years. All were cross-sectional quantitative studies besides one pilot intervention study. Most studies were of small sample size, had low response rate or participants without verified diagnosis. Despite these limitations, most studies indicate that having an HTAAD diagnosis as MFS may negatively impact QoL, but few studies found any associations between the biomedical symptoms and decreased QoL. More research is needed on QoL in samples with verified HTAAD diagnosis to develop evidence-based knowledge and appropriate guidelines for these diagnoses.

Parental-reported neurodevelopmental issues in Loeys-Dietz syndrome.

BACKGROUND: Loeys-Dietz syndrome (LDS) is a congenital multisystem disorder affecting the cardiovascular and musculoskeletal system. Limited data have reported neurodevelopmental (ND) issues in LDS. AIMS: To determine the extent of ND issues in patients with LDS. METHODS: A prospective study was performed of LDS patients or their caregivers. The study included data collected via an online survey of age-specific questions. Standard statistical methods were used for baseline and demographic characteristics, as well as group comparisons. OUTCOMES: Data were obtained from 67 patients with LDS (54% female). Median age was 14.9 years. Gene mutations included TGFBR1 (39%), TGFBR2 (40%), SMAD3 (7%), and unknown (14%). Motor delays (30%, 18/61) and hypotonia (63%, 37/60) occurred frequently. Physical (62%, 39/62), occupational (41%, 23/56), and speech therapies (34%, 20/58) were common. Feeding issues were common (41%, 23/56). TGFBR1 mutations were more frequent among those with motor delays and feeding issues. CONCLUSIONS: Patients with LDS and/or their caregivers report at least one ND problem in most cases, and many require therapies. These data suggest ND disorders should be considered to be part of the phenotype.

Longitudinal Changes in Segmental Aortic Stiffness Determined by Cardiac Magnetic Resonance in Children and Young Adults With Connective Tissue Disorders (the Marfan, Loeys-Dietz, and Ehlers-Danlos Syndromes, and Nonspecific Connective Tissue Disorders).

Aortic stiffness measured by cardiac magnetic resonance (CMR) in connective tissue disorder (CTD) patients has been previously shown to be abnormal and to be associated with adverse aortic outcomes. The rate of increase in aortic stiffness with normal aging has been previously described. However, longitudinal changes in aortic stiffness have not been characterized in CTD patients. We examined longitudinal changes in CMR-derived aortic stiffness in children and young adults with CTDs. A retrospective analysis of 50 children and young adults (median age, 20 years; range, 0.2 to 49; 40% < 18 years old) with a CTD, and with at least 2 CMR examinations (total 152 examinations) over a median duration of 3.9 (1 to 13.2) years was performed. Aortic stiffness measures (strain, distensibility, and ß stiffness index) were calculated on each examination at the aortic root (AoR), ascending aorta, and descending aorta. Longitudinal changes in parameters were analyzed using linear mixed-effects models. Aortic strain and distensibility decreased with age, whereas the ß stiffness index increased at all aortic segments. The average rates of decline in distensibility (x10-3 mm Hg-1 per 10-year increase in age) were 0.7, 1.3, and 1 at the AoR, ascending aorta, and descending aorta, respectively. The rates of decline in distensibility were not associated with the rates of AoR dilation or surgical AoR replacement. In conclusion, on serial CMR measurements in children and young adults with CTDs, aortic stiffness progressively increased with age, with rates of change only slightly higher than those previously reported in healthy adults.

Loeys-Dietz syndrome and pregnancy: The first ten years.

The physiological and haemodynamic changes that occur in pregnancy and the postpartum period increase the risk of aortic dissection. Loeys-Dietz syndrome results from mutations in the genes encoding components of the TGF-ß signalling pathway; aortic pathology is of particular concern in this condition but other vascular abnormalities can also be present. Significant maternal morbidity and mortality has been described in patients with Loeys-Dietz syndrome, but successful and uncomplicated pregnancies are still possible. Nevertheless, all patients with this condition should, at present, be treated as very high risk in pregnancy and the postpartum period, until reliable risk prediction tools become available. This review summarises the recent advances in the understanding of the pathophysiology of this condition, and the management strategies currently advocated.

Phenotypic variability and diffuse arterial lesions in a family with Loeys-Dietz syndrome type 4.

Syndromic thoracic aortic aneurysm and dissection (TAAD) can suggest Marfan, vascular Ehlers-Danlos or Loeys-Dietz (LDS) syndromes. Several of the TGFß-pathway-related genes predispose to different types of LDS. Heterozygous loss-of-function variations in TGFß2 have been shown to be responsible for a novel form of syndromic TAAD associated with an impairment of the mitral valve and cerebrovascular disease called Loeys-Dietz syndrome type 4 (LDS4). We report the clinical characterization of a LDS4 French family with sudden deaths and diffuse vascular lesions, caused by a frameshift mutation in TGFß2 gene: c.[995del]; p.(Leu332TrpfsTer27). Clinical characteristics include aneurysm of aortic sinus, skeletal and cutaneous features compatible with a syndromic form of TAAD (joint hypermobility, scoliosis, and easy bruises), intracranial aneurysms and rare mitral valve involvement. Iliac aneurysms, systemic medium caliber arteries dissections, and mild developmental delay were present in the family, and have not been described in LDS4. Phenotypic variability was also an important finding, including absence of clinical vascular events at advanced age in one case. Our data expand the phenotype of LDS4: we confirm that TGFß2 mutations are responsible for true LDS syndrome with non-specific features of connective tissue disorders and diffuse vascular lesions. Adapted vascular follow up and prevention has to be proposed for these patients.

LOEYS-DIETZ SYNDROME: PERIOPERATIVE ANESTHESIA CONSIDERATIONS.

Loeys-Dietz syndrome (LDS) is a rare autosomal dominant disease related to genetic mutations in receptors for the cytokine transforming growth factor-receptor type 1 (TGFB-R1) or 2 gene (TGFB-R2) on the cell surface. LDS results in abnormal protein synthesis and dysfunctional connective tissue, which can result in unique cardiovascular anesthesia challenges related to perioperative management. Patients with LDS may manifest hypertelorism, bifid uvula or cleft palate, and arterial tortuosity. Virtually all LDS patients show some type of abnormal skin findings and bleeding tendency. These patients may show a rapid progression of aortic dilation, regurgitation, and a propensity towards rupture and/or dissection at a much earlier age and smaller aneurysm size. LDS patients who require surgical intervention require meticulous vigilance from the anesthesiologist. We describe a 26 year old patient with documented LDS type 1 who presented for repair of an ascending/root aneurysm in this case report. Recognition of LDS and intra-operative management of the cardiovascular manifestations of this disease is paramount in ensuring successful surgical outcome and to limit morbidity and mortality.

Pathophysiology and Management of Cardiovascular Manifestations in Marfan and Loeys-Dietz Syndromes.

Marfan syndrome (MFS) is an autosomal dominant heritable disorder of connective tissue that affects the cardiovascular, skeletal, ocular, pulmonary, and nervous systems and is usually caused by mutations in the FBN1 gene, which encodes fibrillin-1. MFS is traditionally considered to result from the structural weakness of connective tissue. However, recent investigations on molecular mechanisms indicate that increased transforming growth factor-ß (TGF-ß) activity plays a crucial role in the pathogenesis of MFS and related disorders, such as Loeys-Dietz syndrome (LDS), which is caused by mutation in TGF-ß signaling-related genes. In addition, recent studies show that angiotensin II type 1 receptor (AT1R) signaling enhances cardiovascular pathologies in MFS, and the angiotensin II receptor blocker losartan has the potential to inhibit aortic aneurysm formation. However, the relationship between TGF-ß and AT1R signaling pathways remains poorly characterized. In this review, we discuss the recent studies on the molecular mechanisms underlying cardiovascular manifestations of MFS and LDS and the ensuing strategies for management.

Spontaneous Coronary Artery Dissection in Loeys-Dietz Syndrome: Role of Optical Coherence Tomography in Diagnosis and Management.

Coronary artery aneurysm with dissection is an uncommon presentation of Loeys-Dietz syndrome (LDS). Diagnosis and management of patients with LDS who present with unstable clinical syndromes merit special attention given unique pathophysiology derangements associated with this disease entity. Clinical experience in treating such patients is limited to a few case reports, and an optimal catheter-based treatment approach is less well defined. Intravascular imaging techniques, particularly optical coherence tomography (OCT), are able to provide further insight about the morphology of lesions and guide-catheter based intervention. In this case report, we describe one such patient and highlight the key morphological characteristics of coronary artery disease in patients with LDS as well as the crucial role of OCT in its management.

Differential diagnosis and diagnostic flow chart of joint hypermobility syndrome/ehlers-danlos syndrome hypermobility type compared to other heritable connective tissue disorders.

Joint hypermobility syndrome/Ehlers-Danlos syndrome hypermobility type (JHS/EDS-HT) is an evolving and protean disorder mostly recognized by generalized joint hypermobility and without a defined molecular basis. JHS/EDS-HT also presents with other connective tissue features affecting a variety of structures and organs, such as skin, eye, bone, and internal organs. However, most of these signs are present in variable combinations and severity in many other heritable connective tissue disorders. Accordingly, JHS/EDS-HT is an "exclusion" diagnosis which needs the absence of any consistent feature indicative of other partially overlapping connective tissue disorders. While both Villefranche and Brighton criteria include such an exclusion as a mandatory item, a systematic approach for reaching a stringent clinical diagnosis of JHS/EDS-HT is still lacking. The absence of a consensus on the diagnostic approach to JHS/EDS-HT concerning its clinical boundaries with similar conditions contribute to limit our actual understanding of the pathologic and molecular bases of this disorder. In this review, we revise the differential diagnosis of JHS/EDS-HT with those heritable connective tissue disorders which show a significant overlap with the former and mostly include EDS classic, vascular and kyphoscoliotic types, osteogenesis imperfecta, Marfan syndrome, Loeys-Dietz syndrome, arterial tortuosity syndrome, and lateral meningocele syndrome. A diagnostic flow chart is also offered with the attempt to support the less experienced clinician in stringently recognizing JHS/EDS-HT and stimulate the debate in the scientific community for both management and research purposes.

The neuromuscular differential diagnosis of joint hypermobility.

Joint hypermobility is the defining feature of various inherited connective tissue disorders such as Marfan syndrome and various types of Ehlers-Danlos syndrome and these will generally be the first conditions to be considered by geneticists and pediatricians in the differential diagnosis of a patient presenting with such findings. However, several congenital and adult-onset inherited myopathies also present with joint hypermobility in the context of often only mild-to-moderate muscle weakness and should, therefore, be included in the differential diagnosis of joint hypermobility. In fact, on the molecular level disorders within both groups represent different ends of the same spectrum of inherited extracellular matrix (ECM) disorders. In this review we will summarize the measures of joint hypermobility, illustrate molecular mechanisms these groups of disorders have in common, and subsequently discuss the clinical features of: 1) the most common connective tissue disorders with myopathic or other neuromuscular features: Ehlers-Danlos syndrome, Marfan syndrome and Loeys-Dietz syndrome; 2) myopathy and connective tissue overlap disorders (muscle extracellular matrix (ECM) disorders), including collagen VI related dystrophies and FKBP14 related kyphoscoliotic type of Ehlers-Danlos syndrome; and 3) various (congenital) myopathies with prominent joint hypermobility including RYR1- and SEPN1-related myopathy. The aim of this review is to assist clinical geneticists and other clinicians with recognition of these disorders.

Skeletal overgrowth syndrome caused by overexpression of C-type natriuretic peptide in a girl with balanced chromosomal translocation, t(1;2)(q41;q37.1).

Chromosomal translocation of 2q37.1 just distal to the NPPC gene coding for C-type natriuretic peptide (CNP) and subsequent overproduction of CNP have been reported to cause a skeletal overgrowth syndrome. Loeys-Dietz syndrome (LDS) is one of marfanoid overgrowth syndromes, of which subtype IV is caused by haploinsufficiency of transforming growth factor beta 2 (TGFB2). We report on a girl with clinical phenotypes of overgrowth syndrome, including long and slim body habitus, macrodactyly of the big toe, scoliosis, ankle valgus deformity, coxa valga, slipped capital femoral epiphysis, and aortic root dilatation. Karyotyping revealed a balanced chromosomal translocation between 1q41 and 2q37.1, and the breakpoints could be mapped by targeted resequencing analysis. On chromosome 2q37.1, the translocation took place 200,365 bp downstream of NPPC, and serum level of the amino terminal of CNP was elevated. The contralateral site of translocation on chromosome 1q41 disrupted TGFB2 gene, presumed to cause its haploinsufficiency. This case supports the concept that NPPC is overexpressed because of the loss of a specific negative regulatory control in the normal chromosomal location, and demonstrates the effectiveness of targeted resequencing in the mapping of breakpoints.