Differences in manifestations of Marfan syndrome, Ehlers-Danlos syndrome, and Loeys-Dietz syndrome

Management of a pregnant woman with Marfan syndrome and aortic root and aberrant right subclavian artery aneurysm: a case report

Background

Marfan syndrome is a genetic connective tissue disorder that commonly affects the cardiovascular, skeletal, and ocular system. The increased risk of developing thoracic aortic aneurysms that can lead to aortic dissection and rupture is the main source of mortality in these patients. Pregnancy-induced changes can further increase the risk for aortic complications, especially in patients with an aortic root diameter > 45 mm.

Case summary

The case of a 26-year-old female with Marfan syndrome who was lost to follow-up for five years and presented to our department being pregnant at 21 weeks is presented. Echocardiography and cardiovascular magnetic resonance (CMR) showed an aortic root diameter of 55 mm and a large aneurysm of an aberrant right subclavian artery. Following multidisciplinary team discussion, valve-sparing aortic root and ascending aortic replacement was performed at 22 weeks of gestation without any complications. During the remaining pregnancy, the patient had frequent clinical and CMR follow-up investigations showing a mild increased size of the subclavian aneurysm. Uncomplicated caesarean delivery was performed at 35 weeks of gestation, and the subclavian artery aneurysm was successfully treated by interventional embolization.

Discussion

Although cardiovascular surgery in our patient during pregnancy was uncomplicated, the case illustrates that pre-pregnancy counselling in Marfan patients is recommended to reduce the risk for mother and child.

Arterial aneurysm and dissection: toward the evolving phenotype of Tatton-Brown-Rahman syndrome

BACKGROUND

Tatton-Brown-Rahman syndrome (TBRS) is a rare disorder, caused by DNMT3A heterozygous pathogenic variants, and first described in 2014. TBRS is characterised by overgrowth, intellectual disability, facial dysmorphism, hypotonia and musculoskeletal features, as well as neurological and psychiatric features. Cardiac manifestations have also been reported, mainly congenital malformations such as atrial septal defect, ventricular septal defect and cardiac valvular disease. Aortic dilatation has rarely been described.

METHODS

Here we have undertaken a detailed clinical and molecular description of eight previously unreported individuals, who had TBRS and arterial dilatation and/or dissection, mainly thoracic aortic aneurysm (TAA). We have also reviewed the seven previously published cases of TAA in individuals with TBRS to try to better delineate the vascular phenotype and to determine specific follow-up for this condition.

RESULTS

We include eight new patients with TBRS who presented with arterial aneurysms mainly involving aorta. Three of these patients presented with dissection that required critical surgery.

CONCLUSIONS

Arterial aneurysms and dissections are a potentially lethal, age-dependent manifestation. The prevalence of aortic disease in individuals with TBRS is far in excess of that expected in the general population. This cohort, together with individuals previously published, illustrates the importance to consider dilatation/dissection, mainly in aorta but also in other arteries. Arterial vascular weakness may therefore also be a cardinal feature of TBRS and vascular surveillance is recommended.

Instrumentation of hypoplastic pedicles with patient-specific guides

PURPOSE

Hypoplastic pedicles of the thoracolumbar spine (<5 mm diameter) are often found in syndromic deformities of the spine and pose a challenge in pedicle screw instrumentation. 3D-printed patient-specific guides might help overcome anatomical difficulties when instrumenting pedicles with screws, thereby reducing the necessity for less effective fixation methods such as hooks or sublaminar wires. In this study, the surgical feasibility and clinical outcome of patients with hypoplastic pedicles following pedicle screw instrumentation with 3D-printed patient-specific guides were assessed.

METHODS

Hypoplastic pedicles were identified on preoperative computed tomography (CT) scans in six patients undergoing posterior spinal fusion surgery between 2017 and 2020. Based on these preoperative CT scans, patient-specific guides were produced to help with screw instrumentation of these thin pedicles. Postoperatively, pedicle-screw-related complications or revisions were analyzed.

RESULTS

93/105 (88.6%) pedicle screws placed with patient-specific guides were instrumented. 62/93 (66.7%) of these instrumented pedicles were defined as hypoplastic with a mean width of 3.07 mm (SD  ±0.98 mm, 95% CI [2.82-3.32]). Overall, 6 complications in the 62 hypoplastic pedicles (9.7%) were observed and included intraoperatively managed 4 cerebrospinal fluid leaks, 1 pneumothorax and 1 delayed revision due to 2 lumbar screws (2/62, 3.3%) impinging the L3 nerve root causing a painful radiculopathy. The mean follow-up time was 26.7 (SD  ±11.7) months. Complications were only noted when the pedicle-width-to-screw-diameter ratio measured less than 0.62.

CONCLUSION

Patient-specific 3D-printed guides can aid in challenging instrumentation of hypoplastic pedicles in the thoracolumbar spine, especially if the pedicle-width-to-screw-diameter ratio is greater than 0.62.

Hypermobility Among Adolescents and the Association With Spinal Deformities: A Large Cross-Sectional Study

INTRODUCTION

Adolescent idiopathic scoliosis and Scheuermann kyphosis are common spinal deformities (SD) among adolescents. The potential link between hypermobility and SD is a topic of debate. We aimed to investigate the prevalence of hypermobility and its association with SD.

METHODS

A cross-sectional analysis of records of 17-year-old subjects who were recruited into mandatory military service was conducted. Study population comprised 1,220,073 subjects. Prevalence rates were calculated for hypermobility and different categories of SD by severity, studying the strength of the association between hypermobility and SD.

RESULTS

Of 1,220,073 subjects, 0.0111% exhibited hypermobility. Spinal deformities were identified in 10.5% of subjects. Specifically, 7.9% had mild SD, 2.4% had moderate SD, and 0.1% had severe SD. The overall association between hypermobility and SD showed an odds ratio of 2.31 (P < 0.001). Subgroup analyses revealed ORs of 1.226 (P = 0.041) for mild deformities, 5.783 (P < 0.001) for moderate deformities, and 4.01 (P = 0.002) for severe deformities. The association was stronger for moderate and severe SD.

CONCLUSIONS

This study establishes a notable association between hypermobility and SD among adolescents. The findings highlight the importance of understanding this relationship, which could contribute to advancements in comprehending SD development. Additional research is warranted to expand upon these findings.

Reproductive decision-making and the utilization of preimplantation genetic testing among individuals with inherited aortic or vascular disease

Preimplantation genetic testing for monogenic disorders (PGT-M) is a reproductive technology used in conjunction with in-vitro fertilization (IVF) to reduce the risk of passing on a known genetic condition from parent to child. There is limited research describing the experience and emotional impact of PGT-M among individuals with inherited aortic or vascular disease (IAVD). Our qualitative study aims to explore the factors that influence reproductive decision-making and the uptake of PGT-M within this population. Individuals diagnosed with IAVD who have considered PGT-M, and/or their reproductive partner, were recruited using internal clinical databases and advocacy organizations. Virtual semi-structured interviews were conducted using an interview guide that included questions related to participants' lived experience of their condition, risk perception, reproductive history, familiarity with PGT-M/IVF, and financial/psychosocial considerations. A total of 17 interviews were completed (13 affected individuals, 4 unaffected partners) and analyzed using thematic analysis. Emergent themes included: (1) the lived experience and perceived severity of disease; (2) need for comprehensive, balanced, and timely information; (3) and impact of personal values and circumstances. When discussing the impact of lived experience on reproductive decision-making, participants identified the physical and emotional impact of disease and variability of disease as factors influencing the uptake of PGT-M. Many described PGT-M as the only reproductive option presented to them by providers. Even so, participants expressed gaps in their understanding of PGT-M, particularly regarding cost/insurance coverage and the experience of IVF. Finally, participants recognized that the decision to pursue PGT-M primarily requires introspection and evaluation of one's values, but that cost remains a significant consideration. The findings from our study highlight the complexity of reproductive decision-making for individuals with IAVD and provide insight into their psychological and informational needs when engaging in this process. Providers can use these findings to tailor their discussions about reproductive decision-making with this patient cohort.

Marfan and Loeys-Dietz aortic phenotype: A potential tool for diagnosis and management

Objective

In heritable aortic diseases, different vascular involvement may occur with potential variable implications in aortic dilation/dissection risk. This study aimed to analyze the aortic anatomy of individuals with Marfan syndrome and Loeys-Dietz syndrome to identify possible morphological differences.

Methods

Computed tomography and magnetic resonance imaging of the thoracoabdominal aorta from the proximal supra-aortic vessels to the femoral bifurcation level of 114 patients with Marfan and Loeys-Dietz syndromes and 20 matched control subjects were examined. Aortic diameters, areas, length, and tortuosity were measured in different aortic segments using specific vessel analysis software.

Results

Patients with Marfan syndrome showed a higher prevalence of ascending aorta and aortic root dilation (P = .011), larger and longer aortic roots (P = .013) with pear-shaped phenotype, larger isthmus/descending aorta diameter ratio (P = .015), and larger suprarenal aorta and iliac arteries. Patients with Loeys-Dietz syndrome showed longer indexed segments and a significantly longer arch (P = .006) with type 2/3 arch prevalence (P = .097). Measurement ratios analysis provided cut-off values (aortic root to ascending aorta length/aortic root diameter, aortic root/sinotubular junction, aortic root/ascending aorta diameter) differentiating patients with Marfan syndrome from patients with Loeys-Dietz syndrome, even in the early stage of the disease.

Conclusions

Both syndromes show peculiar anatomic patterns at different aortic levels irrespective of aortic dilation and disease severity. These features may represent the expression of different genetic mutations on aortic development, with a potential impact on prognosis and possibly contributing to better management of the diseases. The systematic adoption of whole body imaging with magnetic resonance or computed tomography should always be considered, because they allow a complete vascular assessment with practical indicators of differential diagnosis.

A new procedure to induce aortic aneurysms in mice

Aortic aneurysms (AAs) are a major public health challenge, featured by a progressive impairs in aortic wall integrity that drives to aortic dilation and, in end stage, to its rupture. Despite important advances in the surgical treatment of aortic aneurysms, there is currently no pharmacological intervention that prevents their development, reduces their expansion, or avoids their rupture. In addition to classic risk factors such age or gender, several heritable connective tissue disorders have been associated with AA developing, highlighting the role of extracellular matrix (ECM) genes alterations in the developing of AA. In this sense, we have recently demonstrated that global deletion of the cellular communicating network factor 2 (CCN2), previously known as connective tissue growth factor (CTGF) due to its role in the extracellular matrix formation, predisposes to early and lethal AAs development after Angiotensin II (Ang II) infusion in mice. Here, we detail the protocol to induce and detect AAs generation in inducible global CCN2 knockout mice after Ang II infusion which allow the characterization of CCN role in AA development and may help to the development of pharmacological target for AA treatment.

Elucidating VSMC phenotypic transition mechanisms to bridge insights into cardiovascular disease implications

Cardiovascular diseases (CVD) are the leading cause of death worldwide, despite advances in understanding cardiovascular health. Significant barriers still exist in effectively preventing and managing these diseases. Vascular smooth muscle cells (VSMCs) are crucial for maintaining vascular integrity and can switch between contractile and synthetic functions in response to stimuli such as hypoxia and inflammation. These transformations play a pivotal role in the progression of cardiovascular diseases, facilitating vascular modifications and disease advancement. This article synthesizes the current understanding of the mechanisms and signaling pathways regulating VSMC phenotypic transitions, highlighting their potential as therapeutic targets in cardiovascular disease interventions.

Bioengineered vascular grafts with a pathogenic TGFBR1 variant model aneurysm formation in vivo and reveal underlying collagen defects

Thoracic aortic aneurysm (TAA) is a life-threatening vascular disease frequently associated with underlying genetic causes. An inadequate understanding of human TAA pathogenesis highlights the need for better disease models. Here, we established a functional human TAA model in an animal host by combining human induced pluripotent stem cells (hiPSCs), bioengineered vascular grafts (BVGs), and gene editing. We generated BVGs from isogenic control hiPSC-derived vascular smooth muscle cells (SMCs) and mutant SMCs gene-edited to carry a Loeys-Dietz syndrome (LDS)-associated pathogenic variant (TGFBR1A230T). We also generated hiPSC-derived BVGs using cells from a patient with LDS (PatientA230T/+) and using genetically corrected cells (Patient+/+). Control and experimental BVGs were then implanted into the common carotid arteries of nude rats. The TGFBR1A230T variant led to impaired mechanical properties of BVGs, resulting in lower burst pressure and suture retention strength. BVGs carrying the variant dilated over time in vivo, resembling human TAA formation. Spatial transcriptomics profiling revealed defective expression of extracellular matrix (ECM) formation genes in PatientA230T/+ BVGs compared with Patient+/+ BVGs. Histological analysis and protein assays validated quantitative and qualitative ECM defects in PatientA230T/+ BVGs and patient tissue, including decreased collagen hydroxylation. SMC organization was also impaired in PatientA230T/+ BVGs as confirmed by vascular contraction testing. Silencing of collagen-modifying enzymes with small interfering RNAs reduced collagen proline hydroxylation in SMC-derived tissue constructs. These studies demonstrated the utility of BVGs to model human TAA formation in an animal host and highlighted the role of reduced collagen modifying enzyme activity in human TAA formation.

Investigation of Strategies to Block Downstream Effectors of AT1R-Mediated Signalling to Prevent Aneurysm Formation in Marfan Syndrome

Cardiovascular outcome in Marfan syndrome (MFS) patients most prominently depends on aortic aneurysm progression with subsequent aortic dissection. Angiotensin II receptor blockers (ARBs) prevent aneurysm formation in MFS mouse models. In patients, ARBs only slow down aortic dilation. Downstream signalling from the angiotensin II type 1 receptor (AT1R) is mediated by G proteins and β-arrestin recruitment. AT1R also interacts with the monocyte chemoattractant protein-1 (MCP-1) receptor, resulting in inflammation. In this study, we explore the targeting of β-arrestin signalling in MFS mice by administering TRV027. Furthermore, because high doses of the ARB losartan, which has been proven beneficial in MFS, cannot be achieved in humans, we investigate a potential additive effect by combining lower concentrations of losartan (25 mg/kg/day and 5 mg/kg/day) with barbadin, a β-arrestin blocker, and DMX20, a C-C chemokine receptor type 2 (CCR2) blocker. A high dose of losartan (50 mg/kg/day) slowed down aneurysm progression compared to untreated MFS mice (1.73 ± 0.12 vs. 1.96 ± 0.08 mm, p = 0.0033). TRV027, the combination of barbadin with losartan (25 mg/kg/day), and DMX-200 (90 mg/kg/day) with a low dose of losartan (5 mg/kg/day) did not show a significant beneficial effect. Our results confirm that while losartan effectively halts aneurysm formation in Fbn1C1041G/+ MFS mice, neither TRV027 alone nor any of the other compounds combined with lower doses of losartan demonstrate a notable impact on aneurysm advancement. It appears that complete blockade of AT1R function, achieved by administrating a high dosage of losartan, may be necessary for inhibiting aneurysm progression in MFS.

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.

Re-evaluation of a Fibrillin-1 Gene Variant of Uncertain Significance Using the ClinGen Guidelines

Background

Marfan syndrome (MFS) is caused by fibrillin-1 gene (FBN1) variants. Mutational hotspots and/or well-established critical functional domains of FBN1 include cysteine residues, calcium-binding consensus sequences, and amino acids related to interdomain packaging. Previous guidelines for variant interpretation do not reflect the features of genes or related diseases. Using the Clinical Genome Resource (ClinGen) FBN1 variant curation expert panel (VCEP), we re-evaluated FBN1 germline variants reported as variants of uncertain significance (VUSs).

Methods

We re-evaluated 26 VUSs in FBN1 reported in 161 patients with MFS. We checked the variants in the Human Genome Mutation Database, ClinVar, and VarSome databases and assessed their allele frequencies using the gnomAD database. Patients' clinical information was reviewed.

Results

Four missense variants affecting cysteines (c.460T>C, c.1006T>C, c.5330G>C, and c.8020T>C) were reclassified as likely pathogenic and were assigned PM1_strong or PM1. Two intronic variants were reclassified as benign by granting BA1 (stand-alone). Four missense variants were reclassified as likely benign. BP5 criteria were applied in cases with an alternate molecular basis for disease, one of which (c.7231G>A) was discovered alongside a pathogenic de novo COL3A1 variant (c.1988G>T, p.Gly633Val).

Conclusions

Considering the high penetrance of FBN1 variants and clinical variability of MFS, the detection of pathogenic variants is important. The ClinGen FBN1 VCEP encompasses mutational hotspots and/or well-established critical functional domains and adjusts the criteria specifically for MFS; therefore, it is beneficial not only for identifying pathogenic FBN1 variants but also for distinguishing these variants from those that cause other connective tissue disorders with overlapping clinical features.

Integrative medicine for hypermobility spectrum disorders (HSD) and Ehlers-Danlos syndromes (EDS): a feasibility study

PURPOSE

Hypermobility spectrum disorders (HSD) and Ehlers-Danlos syndromes (EDS) are multisystem conditions marked by dysfunctional connective tissue. This feasibility study evaluated a 9-week integrative medicine program in this population.

METHODS

Using a single-arm study design, adults with HSD or EDS were given recommendations for an anti-inflammatory Mediterranean diet and self-management with additional behavioral and psychosocial support. Preliminary data on feasibility based on recruitment and retention, adherence to the diet, mobile app tracking, changes to perceived well-being via health outcomes, and satisfaction with care were obtained.

RESULTS

Thirteen participants were enrolled within a 4-month timeframe. Eight participants completed the study. Three participants met dietary tracking requirement in at least 4 of 8 intervention weeks and met the macronutrient requirements in at least half of the weeks tracked. No decreases in VAS pain scores after 5 and 9 weeks were noted; however, 62.5% (n = 5) of participants had decreased pain at 9 weeks, compared to baseline. There were significant improvements (p<.05) in six of twelve measurements of satisfaction with care at the end of the intervention.

CONCLUSION

This study provides a foundation for future research on patient experience and introduces a novel treatment paradigm focused on nutrition and self-management.

Trial Registration: National Institutes of Health clinicaltrials.gov; identifier: NCT04734041.

IMPLICATIONS FOR REHABILITATION

Lifestyle and dietary interventions are relatively safe and well tolerated in the hypermobility spectrum disorder (HSD) and Ehlers-Danlos disorder (EDS) population.Participants in our 9-week integrative medicine program actively engaged in self-management of their condition and showed promising adherence to dietary and tracking requirements.Effective treatment of the intricacies and dynamics of these highly variable and clinically heterogeneous disorders may require a network of healthcare providers, integrative healthcare, as well as behavioral and psychosocial support.Dietary tracking through mobile apps might help promote self-efficacy and adherence to dietary changes.Symptom tracking might be an effective way for patients to track changes to their health and could provide valuable information for health professionals engaged in managing the disorders.

Microvascular Capillary and Precapillary Cardiovascular Disturbances Strongly Interact to Severely Affect Tissue Perfusion and Mitochondrial Function in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Evolving from the Post COVID-19 Syndrome

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a frequent, debilitating and still enigmatic disease. There is a broad overlap in the symptomatology of ME/CFS and the Post-COVID-19 Syndrome (PCS). A fraction of the PCS patients develop the full clinical picture of ME/CFS. New observations in microvessels and blood from patients suffering from PCS have appeared and include microclots and malformed pathological blood cells. Capillary blood flow is impaired not only by pathological blood components but also by prothrombotic changes in the vascular wall, endothelial dysfunction, and the expression of adhesion molecules in the capillaries. These disturbances can finally cause a low capillary flow and even capillary stasis. A low cardiac stroke volume due to hypovolemia and the inability of the capacitance vessels to adequately constrict to deliver the necessary cardiac preload generate an unfavorable low precapillary perfusion pressure. Furthermore, a predominance of vasoconstrictor over vasodilator influences exists, in which sympathetic hyperactivity and endothelial dysfunction play a strong role, causing the constriction of resistance vessels and of precapillary sphincters, which leads to a fall in capillary pressure behind the sphincters. The interaction of these two precapillary cardiovascular mechanisms causing a low capillary perfusion pressure is hemodynamically highly unfavorable in the presence of a primary capillary stasis, which is already caused by the pathological blood components and their interaction with the capillary wall, to severely impair organ perfusion. The detrimental coincidence of microcirculatory and precapillary cardiovascular disturbances may constitute the key disturbance of the Post-COVID-19 syndrome and finally lead to ME/CFS in predisposed patients because the interaction causes a particular kind of perfusion disturbance-capillary ischemia/reperfusion-which has a high potential of causing mitochondrial dysfunction by inducing sodium- and calcium-overload in skeletal muscles. The latter, in turn, worsens the vascular situation through the generation of reactive oxygen species to close a vicious cycle from which the patient can hardly escape.

Survival and repair durability in patients undergoing concomitant aortic valve reimplantation and mitral valve repair

Objective

The study objective was to determine repair durability and survival in patients with and without connective tissue disorders undergoing concomitant aortic valve reimplantation and mitral valve repair.

Methods

From 2002 to 2019, 68 patients underwent concomitant aortic valve reimplantation and mitral valve repair, including 27 patients with Marfan syndrome (39.7%). Follow-up echocardiograms were analyzed using nonlinear multiphase mixed-effects cumulative logistic regression. The regurgitation grade over time was estimated by averaging patient-specific profiles. Survival and freedom from reoperation were estimated by the Kaplan-Meier method.

Results

At 7 years, 11% of patients had aortic insufficiency greater than mild (severe in 2 patients). There was no difference in greater than mild aortic insufficiency between patients with or without Marfan syndrome (P = .37). Twenty percent of patients had progressed to mitral regurgitation greater than mild (severe in only 1 patient). The prevalence of recurrent mitral regurgitation was higher in those without Marfan syndrome, with greater than mild regurgitation increasing to 24% by 2 years and remaining constant thereafter (P = .04). Freedom from reoperation on the aortic valve or mitral valve was 83% at 10 years and did not differ between Marfan syndrome groups. There were no cases of perioperative mortality. Survival at 5 and 10 years was 94% and 87%, respectively, without a difference between those with and without Marfan syndrome.

Conclusions

Patients can undergo a total repair strategy using combined aortic valve reimplantation and mitral valve repair procedures with a low risk of mortality and complications, with favorable freedom from both residual valve regurgitation and reoperation.

The genetics and disease mechanisms of rhegmatogenous retinal detachment

Rhegmatogenous retinal detachment (RRD) is a sight threatening condition that warrants immediate surgical intervention. To date, 29 genes have been associated with monogenic disorders involving RRD. In addition, RRD can occur as a multifactorial disease through a combined effect of multiple genetic variants and non-genetic risk factors. In this review, we provide a comprehensive overview of the spectrum of hereditary disorders involving RRD. We discuss genotype-phenotype correlations of these monogenic disorders, and describe genetic variants associated with RRD through multifactorial inheritance. Furthermore, we evaluate our current understanding of the molecular disease mechanisms of RRD-associated genetic variants on collagen proteins, proteoglycan versican, and the TGF-β pathway. Finally, we review the role of genetics in patient management and prevention of RRD. We provide recommendations for genetic testing and prophylaxis of at-risk patients, and hypothesize on novel therapeutic approaches beyond surgical intervention.

Hernia Formation: Risk Factors and Biology

The incidence of ventral hernias in the United States is in increasing. Herein, the author details the etiology of congenital and acquired ventral hernias as well as the risk factors associated with the development of each of these types of ventral hernias.

Extracellular Matrix Remodeling in Vascular Disease: Defining Its Regulators and Pathological Influence

Because of structural and cellular differences (ie, degrees of matrix abundance and cross-linking, mural cell density, and adventitia), large and medium-sized vessels, in comparison to capillaries, react in a unique manner to stimuli that induce vascular disease. A stereotypical vascular injury response is ECM (extracellular matrix) remodeling that occurs particularly in larger vessels in response to injurious stimuli, such as elevated angiotensin II, hyperlipidemia, hyperglycemia, genetic deficiencies, inflammatory cell infiltration, or exposure to proinflammatory mediators. Even with substantial and prolonged vascular damage, large- and medium-sized arteries, persist, but become modified by (1) changes in vascular wall cellularity; (2) modifications in the differentiation status of endothelial cells, vascular smooth muscle cells, or adventitial stem cells (each can become activated); (3) infiltration of the vascular wall by various leukocyte types; (4) increased exposure to critical growth factors and proinflammatory mediators; and (5) marked changes in the vascular ECM, that remodels from a homeostatic, prodifferentiation ECM environment to matrices that instead promote tissue reparative responses. This latter ECM presents previously hidden matricryptic sites that bind integrins to signal vascular cells and infiltrating leukocytes (in coordination with other mediators) to proliferate, invade, secrete ECM-degrading proteinases, and deposit injury-induced matrices (predisposing to vessel wall fibrosis). In contrast, in response to similar stimuli, capillaries can undergo regression responses (rarefaction). In summary, we have described the molecular events controlling ECM remodeling in major vascular diseases as well as the differential responses of arteries versus capillaries to key mediators inducing vascular injury.

Impact of patient demographics and intraoperative characteristics on abdominal aortic aneurysm sac following endovascular repair

BACKGROUND

Endovascular aortic repair (EVAR) has become the preferred treatment for abdominal aortic aneurysm (AAA). Its main aim is to seal the perfusion of the aneurysmal sac and, thus, induce sac regression and subsequent aortic remodelling. Aneurysmal sac regression has been linked to the short- and long-term clinical outcomes post-EVAR. It has also been shown to be influenced by endograft device choice, with several of these available commercially. This review summarises and discusses current evidence on the influence of pre- and intraoperative factors on sac regression. Additionally, this review aims to highlight the device-specific variations in sac regression to provide an overall holistic approach to treating AAAs with EVAR.

METHODS

A comprehensive literature search was conducted using multiple electronic databases to identify and extract relevant data.

RESULTS

Female sex, >70 mm original sac diameters, higher pre-procedural fibrinogen levels, smoking and low intra-aneurysmal pressure were found to positively impact sac regression. Whereas renal impairment, ischemic heart disease, high intra-aneurysmal pressure and aneurysm neck thrombus negatively influenced sac regression. Patent lumbar arteries, age, statins and hypercholesterolaemia displayed conflicting evidence regarding sac regression. Regarding the EVAR endografts compared, newer generation devices such as the Anaconda mainly showed the most optimal results.

CONCLUSION

Sac regression following EVAR in AAA is an important prognostic factor for morbidity and mortality. Nevertheless, several pre- and intraoperative factors can have an influence on sac regression. Therefore, it is necessary to take them into account when assessing AAA patients for EVAR to optimise outcomes. The choice of EVAR stent-graft can also affect sac regression, with evidence suggesting that the Fenestrated Anaconda is associated with the most favourable results.

Variable clinical expression of a Belgian TGFB3 founder variant suggests the presence of a genetic modifier

Background: TGFB3 variants cause Loeys-Dietz syndrome type 5, a syndromic form of thoracic aortic aneurysm and dissection. The exact disease phenotype is hard to delineate because of few identified cases and highly variable clinical representation. Methodology: We provide the results of a haplotype analysis and a medical record review of clinical features of 27 individuals from 5 different families, originating from the Campine region in Flanders, carrying the NM_003239.5(TGFB3):c.787G>C p.(Asp263His) likely pathogenic variant, dbSNP:rs796051886, ClinVar:203492. The Asp263 residue is essential for integrin binding to the Arg-Gly-Asp (RGD) motif of the TGFβ3-cytokine. Results: The haplotype analysis revealed a shared haplotype of minimum 1.92 Mb and maximum 4.14 Mb, suggesting a common founder originating >400 years ago. Variable clinical features included connective tissue manifestations, non-aneurysmal cardiovascular problems such as hypertrophic cardiomyopathy, bicuspid aortic valve, mitral valve disease, and septal defects. Remarkably, only in 4 out of the 27 variant-harboring individuals, significant aortic involvement was observed. In one family, a 31-year-old male presented with type A dissection. In another family, the male proband (65 years) underwent a Bentall procedure because of bicuspid aortic valve insufficiency combined with sinus of Valsalva of 50 mm, while an 80-year-old male relative had an aortic diameter of 43 mm. In a third family, the father of the proband (75 years) presented with ascending aortic aneurysm (44 mm). Conclusion: The low penetrance (15%) of aortic aneurysm/dissection suggests that haploinsufficiency alone by the TGFB3 variant may not result in aneurysm development but that additional factors are required to provoke the aneurysm phenotype.

Genetic Basis, New Diagnostic Approaches, and Updated Therapeutic Strategies of the Syndromic Aortic Diseases: Marfan, Loeys-Dietz, and Vascular Ehlers-Danlos Syndrome

Syndromic aortic diseases (SADs) encompass various pathological manifestations affecting the aorta caused by known genetic factors, such as aneurysms, dissections, and ruptures. However, the genetic mutation underlying aortic pathology also gives rise to clinical manifestations affecting other vessels and systems. As a consequence, the main syndromes currently identified as Marfan, Loeys-Dietz, and vascular Ehlers-Danlos are characterized by a complex clinical picture. In this contribution, we provide an overview of the genetic mutations currently identified in order to have a better understanding of the pathogenic mechanisms. Moreover, an update is presented on the basis of the most recent diagnostic criteria, which enable an early diagnosis. Finally, therapeutic strategies are proposed with the goal of improving the rates of patient survival and the quality of life of those affected by these SADs.

Smooth Muscle Heterogeneity and Plasticity in Health and Aortic Aneurysmal Disease

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

Aortic Dissection in a Young Patient With Unsuspected Aortopathy

Aortic dissection is often a fatal condition if not recognized and treated emergently. Fortunately, it is extremely rare in children and adolescents. We report a case of an adolescent boy who survived an aortic dissection due to severe aortic root dilation. A comprehensive history and physical examination, including family history, can facilitate an early diagnosis of connective tissue diseases, such as Loeys-Dietz syndrome (LDS).

Therapeutic difficulties in a patient with Ehlers-Danlos syndrome and numerous symptomatic premature ventricular contractions-case report and literature review

A 28-year-old female patient diagnosed with Ehlers-Danlos syndrome type III (hypermobile EDS, hEDS) was admitted to the cardiology clinic due to a 3-year history of symptomatic ventricular arrhythmia in the form of multiple premature ventricular contractions (PVCs). Attempts at antiarrhythmic treatment with beta-blockers, propafenone, and verapamil were unsuccessful. Due to the diagnosis of hEDS and the high risk of vascular complications related to the ablation procedure, invasive treatment was abandoned, and it was decided to implement flecainide. After the flecainide treatment initiation, a spectacular improvement in the number of ventricular arrhythmias was observed, along with the disappearance of the complaints previously reported by the patient. To the best of our knowledge, this is the first described case of spectacular flecainide antiarrhythmic effect in a patient with numerous PVCs also diagnosed with EDS. Flecainide treatment in the EDS group could be a successful alternative to ablation, which can lead to serious vascular and even life-threatening complications, especially after the failure of propafenone and beta-blockers treatment.

Connective tissue disorders and eye: A review and recent updates

Collagen vascular disorders (CVDs), also known as connective tissue diseases (CTDs), are a heterogeneous group of entities that affect the connective tissues and are capable of causing end-organ damage to multiple systems, primarily cardiopulmonary and musculoskeletal. However, the occurrence and severity are highly variable among patients. Ocular involvement occurs in a significant number of these disorders and may precede the onset of other extraocular features, thereby serving as an important marker in the diagnosis of these diseases. A timely and accurate diagnosis enables the management of complications. CTDs are primarily immune-mediated inflammatory diseases; however, classifications have encompassed heritable disorders affecting collagen-containing structures and disorders of vascular development. A review of literature published until 25 January 2022 and collected from various databases using the relevant keywords was conducted. All publications (original articles, review articles, as well as case reports) describing the ocular features in CTDs were studied in detail. The objective of this review is to recognize the common ophthalmic presentations of various autoimmune and heritable CTDs, distinguish them from overlapping diseases, elaborate on the prognosis and management of these varied eye presentations, and deliberate on their impact on other ophthalmic surgeries.

TGFβ signaling pathways in human health and disease

Transforming growth factor beta (TGFβ) is named for the function it was originally discovered to perform-transformation of normal cells into aggressively growing malignant cells. It became apparent after more than 30 years of research, however, that TGFβ is a multifaceted molecule with a myriad of different activities. TGFβs are widely expressed with almost every cell in the human body producing one or another TGFβ family member and expressing its receptors. Importantly, specific effects of this growth factor family differ in different cell types and under different physiologic and pathologic conditions. One of the more important and critical TGFβ activities is the regulation of cell fate, especially in the vasculature, that will be the focus of this review.

Fatigue in patients with syndromic heritable thoracic aortic disease: a systematic review of the literature and a qualitative study of patients' experiences and perceptions

INTRODUCTION

The purpose of this study was to explore the literature on fatigue in patients with syndromic heritable thoracic aortic disease (sHTAD), including Marfan syndrome (MFS), Loeys-Dietz syndrome (LDS), vascular Ehlers Danlos syndrome (vEDS) and other sHTADs, critically appraise and synthesize the relevant literature. We also aimed to investigate how adults with sHTAD experience and perceive fatigue, and to discuss clinical implications and direction for further research.

METHODS

First, a systematic review was performed by searching the published literature in all relevant databases and other sources until 20th October 2022. Second, a qualitative focus group interview study was conducted of 36 adults with sHTADs (LDS n = 11, MFS n = 14, vEDS n = 11).

RESULTS

In the systematic review, 33 articles satisfied the eligibility criteria (3 reviews and 30 primary studies). Of the primary studies: 25 dealt with adults (MFS n = 17, MFS/EDS n = 1, EDS n = 2, LDS/vEDS n = 3, different sHTADs n = 2), 5 with children (MFS n = 4, different sHTADs n = 1). Twenty-two were cross-sectional quantitative studies, 4 prospective and 4 qualitative studies. The quality of the included studies was mostly good, but many had small sample sizes, low response rates and/or participants without verified diagnosis. Despite these limitations, studies indicated high prevalence of fatigue (ranging from 37 to 89%), and fatigue was associated with both health and psychosocial aspects. Few studies found that fatigue was associated with disease-related symptoms. In the qualitative focus groups most of the participants reported that they had experienced fatigue which influenced several aspects of life. Four themes related to fatigue were elucidated: (1) different diagnoses-different fatigue?, (2) the nature of fatigue, (3) searches for causes of fatigue, (4) dealing with fatigue in daily life. The four themes seemed mutually interrelated in terms of barriers, strategies and facilitators for dealing with fatigue. The participants experienced fatigue as a consistent dilemma between self-assertion and inadequacy. Fatigue seems to influence several aspects of daily life and may be one of the most debilitating symptoms of having a sHTAD.

CONCLUSION

Fatigue seems to negatively impact the lives of people with sHTADs and should be recognized as an important aspect in the lifelong follow-up of these patients. The life-threatening complications of sHTADs may result in emotional stress, including fatigue and the risk of developing a sedentary lifestyle. Research and clinical initiatives should consider rehabilitation interventions aiming at postponing the onset or reducing symptoms of fatigue.

Somatic symptoms, pain, catastrophizing and the association with disability among children with heritable connective tissue disorders

The aim of the present study was to investigate the nature and prevalence of nonspecific somatic symptoms, pain and catastrophizing in children with Heritable Connective Tissue Disorders (HCTD), and to determine their association with disability. This observational, multicenter study included 127 children, aged 4-18 years, with Marfan syndrome (MFS) (59%), Loeys-Dietz syndrome (LDS) (8%), Ehlers-Danlos syndromes (EDS) (12%) and hypermobile Ehlers-Danlos syndrome (hEDS) (23%). The assessments included the Children's Somatization Inventory or parent proxy (CSI, PCSI), pain visual-analogue scale (VAS), SUPERKIDZ body diagram, Pain Catastrophizing Scale Child or parent proxy (PCS-C, PCS-P) and Childhood Health Assessment Questionnaire (CHAQ-30). Data from children aged ≥8 years were compared to normative data. In children ≥ 8 years (n = 90), pain was present in 59%, with a median of 4 (IQR = 3-9) pain areas. Compared to normative data, the HCTD group reported significantly higher on the CSI (p ≤ 0.001, d = 0.85), VAS pain intensity (p ≤ 0.001, d = 1.22) and CHAQ-30 (p ≤ 0.001, d = 1.16) and lower on the PCS-C (p = 0.017, d = -0.82) and PCS-P (p ≤ 0.001, d = -0.49). The intensity of nonspecific somatic symptoms and pain explained 45% of the variance in disability (r²  = 0.45 F(2,48) = 19.70, p ≤ 0.001). In children ≤ 7 years (n = 37),   pain was present in 35% with a median of 5(IQR = 1-13) pain areas. The mean(SD) VAS scores for pain intensity was 1.5(2.9). Functional disability was moderately correlated to the number of pain areas (r = 0.56, p ≤ 0.001), intensity of nonspecific somatic symptoms (r = 0.63, p ≤ 0.001) and pain (r = 0.83, p ≤ 0.001). In conclusion, this study supports the need for comprehensive assessment of nonspecific somatic symptoms, pain, and disability in children with HCTD to allow tailored treatment.

Retinal detachment in Loeys-Dietz syndrome

Loeys-Dietz syndrome (LDS) is an autosomal-dominant connective-tissue disorder with vascular and musculoskeletal abnormalities similar to Marfan syndrome. However, unlike Marfan, retinal detachment (RD) is rarely reported, and screening protocols do not currently feature ophthalmic assessment or RD counseling. We report a 5-generation family affected by LDS, where RD occurred in six eyes of four individuals. The proband was an 84-year-old male recently diagnosed with type-V LDS (TGFβ3 pathogenic variant c.899G>A, p.(Arg300Gln)). Further investigation was undertaken into the family's medical history. The proband experienced bilateral rhegmatogenous RD at age 60, requiring emergency surgical repair. Other notable ophthalmic features include unusual keratometry, abnormal biometry, and severe hayfever requiring long-term sodium cromoglycate treatment. The proband's sister, father, and uncle had also experienced RDs, all prior to LDS diagnosis. This series demonstrates that RD risk may be significant in LDS, and on occasion the presenting clinical feature. We suggest ophthalmic examination should be added to the initial assessment LDS patients, and patients informed of the early warning symptoms of retinal detachment. As in Marfan syndrome, LDS patients may exhibit cornea plana and abnormal corneal topography, producing atypical biometry. They may also present with allergic conjunctivitis, and awareness of these signs might facilitate earlier diagnosis.

A case of popliteal artery rupture in an 11-year-old patient with vascular Ehlers-Danlos syndrome

We have described a case of multiple surgeries for a ruptured popliteal artery in an 11-year-old female patient with vascular Ehlers-Danlos syndrome. She underwent emergency hematoma evacuation and ruptured popliteal artery interposition with the great saphenous vein graft, which was notably fragile during surgery and had ruptured on the seventh postoperative day. We performed another emergency hematoma evacuation and popliteal artery interposition with an expanded polytetrafluoroethylene vascular graft. Despite the early occlusion of the expanded polytetrafluoroethylene graft, she recovered with mild intermittent claudication in the left lower extremity and was discharged on postoperative day 20 after the first surgery.

The Impact of Genetic Variability of TGF-Beta Signaling Biomarkers in Major Craniofacial Syndromes

Craniofacial development is a complex process involving several signaling pathways, including the one regulated by the TGF-beta (TGF-β) superfamily of growth factors. Isoforms of TGF-β play a vital part in embryonic development, notably in craniofacial patterning. Consequently, pathogenic variants in their coding genes may result in a variety of orofacial and craniofacial malformations. Here, we review the impact of genetic variability of TGF-β signaling biomarkers in major disorders, including palatal and lip clefts, dental anomalies, and craniofacial syndromes, such as the Loeys-Dietz syndrome (LDS) and Camurati-Engelmann disease. Cleft lip and cleft palate are associated with missense mutations in the TGFB1 and TGFB3 genes, while mutations in the LTBP3 gene encoding TGF-β binding protein 3 may cause selective tooth agenesis. Oligodontia may also be caused by TGFB1-inactivating mutations and/or by variations in the GREM2 gene, which disrupt the activity of gremlin 2, a TGF-β/bone morphogenetic protein (BMP4) signaling antagonist. CED may be caused by mutations in the TGFB1 gene, while the TGF-β-related genetic background of LDS consists mostly of TGFBR1 and TGFBR2 mutations, which may also impact the above syndromes' vascular manifestations. The potential utility of the TGF-β signaling pathway factors as biomarkers that correlate genetics with clinical outcome of craniofacial malformations is discussed.

Physical activity and physical fitness in children with heritable connective tissue disorders

Objectives

Health problems in patients with heritable connective tissue disorders (HCTD) are diverse and complex and might lead to lower physical activity (PA) and physical fitness (PF). This study aimed to investigate the PA and PF of children with heritable connective tissue disorders (HCTD).

Methods

PA was assessed using an accelerometer-based activity monitor (ActivPAL) and the mobility subscale of the Pediatric Evaluation of Disability Inventory Computer Adaptive Test (PEDI-CAT). PF was measured in terms of cardiovascular endurance using the Fitkids Treadmill Test (FTT); maximal hand grip strength, using hand grip dynamometry (HGD) as an indicator of muscle strength; and motor proficiency, using the Bruininks-Oseretsky Test of Motor Proficiency-2 (BOTMP-2).

Results

A total of 56 children, with a median age of 11.6 (interquartile range [IQR], 8.8-15.8) years, diagnosed with Marfan syndrome (MFS), n = 37, Loeys-Dietz syndrome (LDS), n = 6, and genetically confirmed Ehlers-Danlos (EDS) syndromes, n = 13 (including classical EDS n = 10, vascular EDS n = 1, dermatosparaxis EDS n = 1, arthrochalasia EDS n = 1), participated. Regarding PA, children with HCTD were active for 4.5 (IQR 3.5-5.2) hours/day, spent 9.2 (IQR 7.6-10.4) hours/day sedentary, slept 11.2 (IQR 9.5-11.5) hours/day, and performed 8,351.7 (IQR 6,456.9-1,0484.6) steps/day. They scored below average (mean (standard deviation [SD]) z-score -1.4 (1.6)) on the PEDI-CAT mobility subscale. Regarding PF, children with HCTD scored well below average on the FFT (mean (SD) z-score -3.3 (3.2)) and below average on the HGD (mean (SD) z-score -1.1 (1.2)) compared to normative data. Contradictory, the BOTMP-2 score was classified as average (mean (SD) z-score.02 (.98)). Moderate positive correlations were found between PA and PF (r(39) = .378, p < .001). Moderately sized negative correlations were found between pain intensity and fatigue and time spent actively (r(35) = .408, p < .001 and r(24) = .395 p < .001, respectively).

Conclusion

This study is the first to demonstrate reduced PA and PF in children with HCTD. PF was moderately positively correlated with PA and negatively correlated with pain intensity and fatigue. Reduced cardiovascular endurance, muscle strength, and deconditioning, combined with disorder-specific cardiovascular and musculoskeletal features, are hypothesized to be causal. Identifying the limitations in PA and PF provides a starting point for tailor-made interventions.

Education and employment status among adults with Loeys-Dietz syndrome and vascular Ehlers-Danlos syndrome in Norway, a questionnaire based study

OBJECTIVES

To describe education level and employment status among adults with Loeys-Dietz syndrome and vascular Ehlers-Danlos syndrome, and explore factors related to work participation.

MATERIALS AND METHODS

Cross-sectional postal survey in 2018. Individuals with molecularly verified diagnosis were recruited through a National Resource Centre for Rare Disorders. A study specific questionnaire included topics on disease burden and validated instruments regarding education level, employment, pain, fatigue, psychological distress, and satisfaction with life.

RESULTS

Fifty persons (56% women) aged 18-67 years, participated. Almost 60% reported education level ≤13 years. Two thirds (66%) received disability benefits, 21 (42%) had full-time disability pension. The median age at ending work was 41 years. Full-time employed and students were younger (p = 0.014), less fatigued (p = 0.035), had less sleep problems (p = 0.028) and higher satisfaction with life (p<0.001) than those who received disability pension. A third (32%) were currently or used to be in sedentary work, and 68% currently had or used to be in practical work requiring much standing and walking (23%), much walking and lifting (34%) or heavy manual work (11%).

CONCLUSIONS

There is a potential that more adults with these diagnoses can sustain employment for more years. Health and social service follow-up routines and future studies should include details on employment perspectives to reveal those at risk of poor employment and to identify modifiable factors for work participation.

SMAD3 mutation in LDS3 causes bone fragility by impairing the TGF-β pathway and enhancing osteoclastogenesis

Loss-of-function mutations in SMAD3 cause Loeys-Dietz syndrome type 3 (LDS3), a rare autosomal-dominant connective tissue disorder characterized by vascular pathology and skeletal abnormalities. Dysregulation of TGF-β/SMAD signaling is associated with abnormal skeletal features and bone fragility. To date, histomorphometric and ultrastructural characteristics of bone with SMAD3 mutations have not been reported in humans and the exact mechanism by which SMAD3 mutations cause the LDS3 phenotype is poorly understood. Here, we investigated bone histomorphometry and matrix mineralization in human bone with a SMAD3 mutation and explored the associated cellular defect in the TGF-β/SMAD pathway in vitro. The index patient had recurrent fractures, mild facial dysmorphism, arachnodactyly, pectus excavatum, chest asymmetry and kyphoscoliosis. Bone histomorphometry revealed markedly reduced cortical thickness (−68 %), trabecular thickness (−32 %), bone formation rate (−50 %) and delayed mineralization. Quantitative backscattered electron imaging demonstrated undermineralized bone matrix with increased heterogeneity in mineralization. The patient's SMAD3 mutation (c.200 T > G; p.I67S), when expressed from plasmid vectors in HEK293 cells, showed reduced phosphorylation and transcription factor activity compared to normal control and SMAD3 (p.S264Y), a gain-of-function mutation, somatic mosaicism of which causes melorheostosis. Transfection study of the patients' SMAD3 (p.I67S) mutation displayed lower luciferase reporter activity than normal SMAD3 and reduced expression of TGF-β signaling target genes. Patient fibroblasts also demonstrated impaired SMAD3 protein stability. Osteoclastogenic differentiation significantly increased and osteoclast-associated genes, including ACP5 (encoding TRAP), ATP6V0D2, and DCSTAMP, were up-regulated in CD14 (+) peripheral blood mononuclear cells (PBMCs) with the SMAD3 (p.I67S) mutation. Upregulation of osteoclastogenic genes was associated with decreased expression of TGF-β signaling target genes. We conclude that bone with the SMAD3 (p.I67S) mutation features reduced bone formation, and our functional studies revealed decreased SMAD3 activation and protein stability as well as increased osteoclastogenesis. These findings enhance our understanding of the pathophysiology of LDS3 caused by SMAD3 mutations. Emerging therapies targeting in the TGF-β/SMAD pathway also raise hope for treatment of LDS3.

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Increased bone fragility

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Low bone matrix mineralization

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SMAD3 (p.I67S) decreased TGF-b signaling and SMAD3 activity.

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SMAD3 (p.I67S) reduced SMAD3 protein stability.

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SMAD3 (p.I67S) mediated osteoclastogenesis.

Computed tomography for aortic assessment in children

Because the aorta is the major vessel of the body, basic knowledge of aortic pathology is essential to the pediatric imager. This review divides aortic pathology into anatomical (e.g., congenital abnormalities) and acquired (e.g., vasculitis, trauma) entities, providing a brief description of pathology, technical considerations in CT acquisition and processing, and some pearls and pitfalls of interpretation. The objective of this paper is to familiarize general pediatric imagers with imaging features of common as well as high-impact aortic pathology on CT and prepare them for acquisition and reporting.

Mass spectrometric analysis of chondroitin sulfate-linked peptides

Chondroitin sulfate proteoglycans (CSPGs) are extracellular matrix components composed of linear glycosaminoglycan (GAG) side chains attached to a core protein. CSPGs play a vital role in neurodevelopment, signal transduction, cellular proliferation and differentiation and tumor metastasis through interaction with growth factors and signaling proteins. These pleiotropic functions of proteoglycans are regulated spatiotemporally by the GAG chains attached to the core protein. There are over 70 chondroitin sulfate-linked proteoglycans reported in cells, cerebrospinal fluid and urine. A core glycan linker of 3-6 monosaccharides attached to specific serine residues can be extended by 20-200 disaccharide repeating units making intact CSPGs very large and impractical to analyze. The current paradigm of CSPG analysis involves digesting the GAG chains by chondroitinase enzymes and analyzing either the protein part, the disaccharide repeats, or both by mass spectrometry. This method, however, provides no information about the site of attachment or the composition of linker oligosaccharides and the degree of sulfation and/or phosphorylation. Further, the analysis by mass spectrometry and subsequent identification of novel CSPGs is hampered by technical challenges in their isolation, less optimal ionization and data analysis. Unknown identity of the linker oligosaccharide also makes it more difficult to identify the glycan composition using database searching approaches. Following chondroitinase digestion of long GAG chains linked to tryptic peptides, we identified intact GAG-linked peptides in clinically relevant samples including plasma, urine and dermal fibroblasts. These intact glycopeptides including their core linker glycans were identified by mass spectrometry using optimized stepped higher energy collision dissociation and electron-transfer/higher energy collision dissociation combined with hybrid database search/de novo glycan composition search. We identified 25 CSPGs including three novel CSPGs that have not been described earlier. Our findings demonstrate the utility of combining enrichment strategies and optimized high-resolution mass spectrometry analysis including alternative fragmentation methods for the characterization of CSPGs.

Supplementary Information

The online version contains supplementary material available at 10.1007/s42485-022-00092-3.

Genotype-phenotype correlations of marfan syndrome and related fibrillinopathies: Phenomenon and molecular relevance

Marfan syndrome (MFS, OMIM: 154700) is a heritable multisystemic disease characterized by a wide range of clinical manifestations. The underlying molecular defect is caused by variants in the FBN1. Meanwhile, FBN1 variants are also detected in a spectrum of connective tissue disorders collectively termed as ‘type I fibrillinopathies’. A multitude of FBN1 variants is reported and most of them are unique in each pedigree. Although MFS is being considered a monogenic disorder, it is speculated that the allelic heterogeneity of FBN1 variants contributes to various manifestations, distinct prognoses, and differential responses to the therapies in affected patients. Significant progress in the genotype–phenotype correlations of MFS have emerged in the last 20 years, though, some of the associations were still in debate. This review aims to update the recent advances in the genotype-phenotype correlations of MFS and related fibrillinopathies. The molecular bases and pathological mechanisms are summarized for better support of the observed correlations. Other factors contributing to the phenotype heterogeneity and future research directions were also discussed. Dissecting the genotype-phenotype correlation of FBN1 variants and related disorders will provide valuable information in risk stratification, prognosis, and choice of therapy.

Intracranial Aneurysms in Loeys-Dietz Syndrome: A Multicenter Propensity-Matched Analysis

BACKGROUND

Loeys-Dietz syndrome (LDS) is an autosomal dominant connective tissue disorder characterized by a classic triad of hypertelorism, bifid uvula and/or cleft palate, and generalized arterial tortuosity. There are limited data on the prevalence and rupture risk of intracranial aneurysms (IAs) in the setting of LDS, with no established guidelines.

OBJECTIVE

To analyze the prevalence and rupture risk of IA in LDS.

METHODS

Electronic medical records of patients with a confirmed diagnosis of LDS and available cerebrovascular imaging were reviewed. Patients were divided into 2 groups based on the presence of IA. Unmatched and propensity-matched analyses were used to identify potential risk factors for aneurysm formation.

RESULTS

Records of 1111 patients were screened yielding a total of 60 patients with a diagnosis of LDS. Eighteen (30%) patients had IA, 4 (22.2%) of whom had multiple aneurysms for a total of 24 IAs. Twenty-three (95.8%) aneurysms were located in the anterior circulation; none of them were ruptured. On unmatched analysis, age ( P = .015), smoking history ( P = .034), hypertension ( P = .035), and number of extracranial aneurysms ( P &lt; .001) were significantly higher in patients with IA. After matching for age, sex, race, stroke history, family history, and extracranial aneurysms, smoking history ( P = .009) remained significant.

CONCLUSION

Patients with LDS have an increased risk of IAs, especially with a history of smoking. The prevalence rate of IAs in our series was 30%. Screening imaging should be considered at diagnosis, and patients should be encouraged to abstain from smoking. Further studies are needed to elucidate the risk of IA rupture and treatment considerations in this unique population.

National trends in thoracic aortic aneurysms and dissections in patients with Marfans and Ehlers Danlos syndrome

INTRODUCTION

Connective tissue disorders predispose patients to earlier aortic dissections and aneurysms. However, there is limited large cohort data given its low incidence.

METHODS

The National Inpatient Sample was searched for all adults with Marfans (MFS) and Ehlers Danlos (EDS) disease between 2010 and 2017. ICD codes were used to select those with a type A aortic dissection or aneurysm.

RESULTS

There was a total of 19,567 cases, giving the estimated incidence of MFS and EDS of 18 and 22.4 per 100k people, respectively. After inclusion criteria, there were 2553 MF and 180 EDS patients. There was no statistical difference in mortality between the MFS and EDS cohorts (4.6% vs. 2.8%, p = .26). EDS patients were more likely to undergo a TEVAR procedure (2.8% vs. 1.0%, p = .03). MF patients were more likely to have a complication of acute kidney injury (p = .02). EDS patients were more likely older (50 vs. 42, p < .001) and female (47% vs. 33%, p < .001). MFS patients were more likely to have a type A aortic dissection (44% vs. 31%, p < .001). The majority (89%) of patients were treated at urban teaching hospitals. On univariable logistic regression, aortic dissection was a predictor for mortality (odds ratio 7.31, p < .001). The type of connective tissue disease was not a significant predictor.

CONCLUSIONS

National level estimates show low mortality for patients with MF or ED presenting to the hospital with aortic dissection or aneurysm. The differences in age and gender can guide surveillance for these patient populations, leading to more elective admissions and reduced hospital mortality.

Ehlers-Danlos syndromes and their manifestations in the visual system

Ehlers-Danlos syndrome (EDS) is a rare, genetically variable, heterogenous group of (currently recognized) thirteen connective tissue disorders characterized by skin hyperextensibility, tissue fragility, and generalized joint hypermobility. In addition to these commonly recognized phenotypes, recent studies have notably highlighted variable ophthalmic features in EDS. In this review, we comprehensively gather and discuss the ocular manifestations of EDS and its thirteen subtypes in the clinical setting.

Embryonic Heterogeneity of Smooth Muscle Cells in the Complex Mechanisms of Thoracic Aortic Aneurysms

Smooth muscle cells (SMCs) are the major cell type of the aortic wall and play a pivotal role in the pathophysiology of thoracic aortic aneurysms (TAAs). TAAs occur in a region-specific manner with the proximal region being a common location. In this region, SMCs are derived embryonically from either the cardiac neural crest or the second heart field. These cells of distinct origins reside in specific locations and exhibit different biological behaviors in the complex mechanism of TAAs. The purpose of this review is to enhance understanding of the embryonic heterogeneity of SMCs in the proximal thoracic aorta and their functions in TAAs.

Pain and fatigue in adults with Loeys-Dietz syndrome and vascular Ehlers-Danlos syndrome, a questionnaire-based study

The purpose was to study self-reported chronic pain and fatigue symptoms among adults with molecularly verified Loeys-Dietz and vascular Ehlers-Danlos syndrome using a cross-sectional questionnaire design. Seventy adults were invited through a National Resource Centre for Rare Disorders. A study specific questionnaire including Brief Pain Inventory, Standardized Nordic Questionnaire, Fatigue Severity Scale, Hospital Anxiety & Depression Scale, questions on physical activity, and disease burden was used. Fifty-two persons participated, n = 34 with Loeys-Dietz and n = 18 with vascular Ehlers-Danlos syndrome, aged 18-68 years, 58% women. Chronic pain (79%) and fatigue (58%) symptoms were common. Half developed pain during childhood/adolescence. Sleep problems and high multi-organ burden were significantly associated with chronic pain (p = 0.004, p = 0.014) and high fatigue (p < 0.001, p < 0.001). Chronic pain was associated with higher scores of fatigue (p = 0.002). Higher scores of fatigue were associated with lower level of physical activity (p = 0.014), higher cardiovascular burden (p = 0.025), and higher symptoms of anxiety (p = 0.001). In this study, symptoms of chronic pain, fatigue, sleep problems, and disease burden seemed to mutually reinforce each other. Initiatives should consider interventions aimed at postponing the onset and reducing symptoms of pain, fatigue, and sleep problems and thus reduce the total disease burden at an early stage in patients with these complex conditions.

Clinical features and complications of Loeys-Dietz syndrome: A systematic review

INTRODUCTION

Loeys-Dietz syndrome (LDS) is a connective tissue disorder that arises from mutations altering the transforming growth factor β signalling pathway. Due to the recent discovery of the underlying genetic mutations leading to LDS, the spectrum of characteristics and complications is not fully understood.

METHODS

Our search included five databases (Pubmed, SCOPUS, Web of Science, EMBASE and google scholar) and included variations of "Loeys-Dietz Syndrome" as search terms, using all available data until February 2021. All study types were included. Three reviewers screened 1394 abstracts, of which 418 underwent full-text review and 392 were included in the final analysis.

RESULTS

We identified 3896 reported cases of LDS with the most commonly reported features and complications being: aortic aneurysms and dissections, arterial tortuosity, high arched palate, abnormal uvula and hypertelorism. LDS Types 1 and 2 share many clinical features, LDS Type 2 appears to have a more aggressive aortic disease. LDS Type 3 demonstrated an increased prevalence of mitral valve prolapse and arthritis. LDS Type 4 and 5 demonstrated a lower prevalence of musculoskeletal and cardiovascular involvement. Amongst 222 women who underwent 522 pregnancies, 4% experienced an aortic dissection and the peripartum mortality rate was 1%.

CONCLUSION

We observed that LDS is a multisystem connective tissue disorder that is associated with a high burden of complications, requiring a multidisciplinary approach. Ongoing attempts to better characterise these features will allow clinicians to appropriately screen and manage these complications.

Femtosecond Laser Combined with Double-Flange Polypropylene Suture Capsular Tension Ring Suspension for the Treatment of Subluxation of Lens in Marfan Syndrome

Purpose

To evaluate the use of femtosecond laser combined with double-flange polypropylene suture capsular tension ring (CTR) suspension to treat subluxation of lens in Marfan syndrome. The objective is to provide safer and more effective surgical procedures for patients. Setting. Eye Hospital, Aier Eye Hospital of Wuhan University, Wuhan, China

Methods

In this retrospective study, we observed sixteen patients (16 eyes) with Marfan syndrome who had undergone this operation. Femtosecond laser incision was performed on the anterior capsule with the lens as the center. The suspending CTR was clipped to anterior capsule to support it, which was secured to the sclera with a double-flange polypropylene suture. Uncorrected visual acuity (UCVA), intraocular pressure (IOP), tilt, and decentration of the intraocular lens (IOL) and postoperative complications were evaluated.

Results

All 16 patients were successfully implanted with suspended CTR and IOL after femtosecond laser assisted surgery. Visual acuity improved significantly after surgery (p < 0.01). At 1 month, 3 months and 6 months postoperatively, the tilt of the IOL was 2.70 ± 0.934, 2.65 ± 0.897, and 2.66 ± 0.781, and the decentration of the IOL was 0.30 ± 0.770, 0.30 ± 0.682, and 0.29 ± 0.737; both had no statistically significant difference between the three groups. After the operation, 4 patients had hyphema and 2 patients experienced a temporary postoperative IOP increase. Only one flange was exposed one month after operation and recovered right after secondary adjustment.

Conclusion

Femtosecond laser combined with double-flange polypropylene suture CTR suspension was effective in fixing the lens capsule to the scleral wall in cases of subluxation of lens seen in Marfan syndrome during our short-term observation. The long-term efficacy of this operation needs further observation and follow-up.

Clinical genetics evaluation and testing of connective tissue disorders: a cross-sectional study

BACKGROUND

Heritable connective tissue disorders (HCTDs) consist of heterogeneous syndromes. The diagnosis of HCTDs is aided by genomic biotechnologies (e.g., next-generation sequencing panels) facilitating the discovery of novel variants causing disease.

METHODS

Detailed clinical exam data and CLIA-approved genetic testing results from next generation sequencing of 74 genes known to play a role in HCTDs were manually reviewed and analyzed in one hundred consecutive, unrelated patients with phenotypic features indicative of a HCTD referred over a 3.5-year period (2016-2020) to a specialized academic genetics clinic. The prevalence of symptoms was evaluated in the context of genetic variants. We also determined if symptoms among different organ systems were related and performed latent class analysis to identify distinct groups of patients based on symptomatology.

RESULTS

In the cohort of 100 consecutive, unrelated individuals there were four pathogenic, six likely pathogenic and 35 classified potentially pathogenic variants of unknown clinical significance. Patients with potentially pathogenic variants exhibited similar symptom profiles when compared to patients with pathogenic/likely pathogenic variants in the same genes. Although results did not meet a multiple testing corrected threshold, patients with connective tissue symptoms had suggestive evidence of increased odds of having skin (odds ratio 2.18, 95% confidence interval 1.12 to 4.24) and eye symptoms (odds ratio 1.89, 95% confidence interval 0.98 to 3.66) requiring further studies. The best performing latent class analysis results were identified when dividing the dataset into three distinct groups based on age, gender and presence or absence of symptoms in the skeletal, connective tissue, nervous, gastrointestinal and cardiovascular systems. These distinct classes of patients included individuals with: (1) minimal skeletal symptoms, (2) more skeletal but fewer connective tissue, nervous or gastrointestinal symptoms and (3) more nervous system symptoms.

CONCLUSIONS

We used novel approaches to characterize phenotype-genotype relationships, including pinpointing potentially pathogenic variants, and detecting unique symptom profiles in patients with features of HCTDs. This study may guide future diagnosis and disease/organ system monitoring with continued improvement and surveillance by clinicians for patients and their families.

Systematic review of the association between isolated musculoskeletal hypermobility and adolescent idiopathic scoliosis

INTRODUCTION

Adolescent idiopathic scoliosis (AIS) affects 1-3% of the population, but its pathogenesis remains unclear. The coexistence of musculoskeletal hypermobility and scoliosis in many inherited syndromes raises the possibility that isolated musculoskeletal hypermobility may contribute to AIS development or progression.

METHODS

We performed a systematic review of the evidence for a relationship between isolated musculoskeletal hypermobility and AIS. A meta-analysis was planned, but if not possible, a narrative evidence synthesis was planned.

RESULTS

Nineteen studies met eligibility criteria for inclusion. One study was excluded due to insufficient quality. Substantial heterogeneity in study design and methodology negated meta-analysis, so a narrative review was performed. Of the 18 studies included, seven suggested a positive association and eight found no association. Three reported the prevalence of musculoskeletal hypermobility in individuals with AIS. Overall, there was no convincing population-based evidence for an association between musculoskeletal hypermobility and AIS, with only two case-control studies by the same authors presenting compelling evidence for an association. Although populations at extremes of hypermobility had a high prevalence of spinal curvature, these studies were at high risk of confounding. Wide variation in methods of measuring musculoskeletal hypermobility and the challenge of assessing AIS in population-based studies hinder study comparison.

CONCLUSIONS

There is a paucity of high-quality evidence examining the association between isolated musculoskeletal hypermobility and AIS. Large-scale prospective studies with adequate adjustment for potential confounding factors could clarify the relationship between musculoskeletal hypermobility and AIS to elucidate its role in the pathogenesis of AIS.