Predicting Marfan Syndrome in Children With Congenital Ectopia Lentis: Development and Validation of a Nomogram

Purpose

To derive an effective nomogram for predicting Marfan syndrome (MFS) in children with congenital ectopia lentis (CEL) using regularly collected data.

Methods

Diagnostic standards (Ghent nosology) and genetic test were applied in all patients with CEL to determine the presence or absence of MFS. Three potential MFS predictors were tested and chosen to build a prediction model using logistic regression. The predictive performance of the nomogram was validated internally through time-dependent receiver operating characteristic curves, calibration curves, and decision curve analysis.

Results

Eyes from 103 patients under 20 years old and with CEL were enrolled in this study. Z score of body mass index (odds ratio [OR] = 0.659; 95% confidence interval [CI], 0.453-0.958), corneal curvature radius (OR = 3.397; 95% CI, 1.829-6.307), and aortic root diameter (OR = 2.342; 95% CI, 1.403-3.911) were identified as predictors of MFS. The combination of the above predictors shows good predictive ability, as indicated by area under the curve of 0.889 (95% CI, 0.826-0.953). The calibration curves showed good agreement between the prediction of the nomogram and the actual observations. In addition, decision curve analysis showed that the nomogram was clinically useful and had better discriminatory power in identifying patients with MFS. For better individual prediction, an online MFS calculator was created.

Conclusions

The nomogram provides accurate and individualized prediction of MFS in children with CEL who cannot be identified with the Ghent criteria, enabling clinicians to personalize treatment plans and improve MFS outcomes.

Translational Relevance

The prediction model may help clinicians identify MFS in its early stages, which could reduce the likelihood of developing severe symptoms and improve MFS outcomes.

Vertebral artery dissection caused by atlantoaxial dislocation in a patient with Marfan syndrome

A small number of case reports have documented a link between atlantoaxial dislocation (AAD) and vertebral artery dissection (VAD), but this association has never been described in patients with hereditary connective tissue disorders. We present a case of an 18-year-old female patient, diagnosed with Marfan syndrome since the age of one, who underwent brain MRA for intracranial aneurysm screening revealing tortuosity of the internal carotid and vertebral arteries as well as atlantoaxial dislocation. Since the patient was asymptomatic, a wait-and-see approach was chosen, but a follow-up MRA after 18 months showed the appearance of a dissecting pseudoaneurysm of the V3 segment of the left vertebral artery. Despite the patient being still asymptomatic, it was decided to proceed with C1-C2 stabilization to prevent further vascular complications. Follow-up imaging showed realignment of the atlantoaxial joint and reduction of the dissecting pseudoaneurysm of the left vertebral artery. In our patient, screening MRA has led to the discovery of asymptomatic arterial and skeletal abnormalities which, if left untreated, might have led to severe cerebrovascular complications. Therefore, AAD correction or close monitoring with MRA should be provided to MFS patients with this craniovertebral junction anomaly, even if asymptomatic.

Quality of life in young patients with acute type a aortic dissection in China: comparison with Marfan syndrome and non-Marfan syndrome

BACKGROUND

There is a paucity of Chinese studies evaluating the quality of life (QoL) in young acute type A aortic dissection (AAAD) patients with Marfan syndrome.

METHODS

Young adult AAAD patients (younger than 45 years old) underwent surgical treatment at our institution from January 2017 to December 2020 were consecutive enrolled. The hospital survivors completed 1 year of follow up. Patients were divided into two groups according to the presence or absence of Marfan syndrome (MFS). A 1:1 propensity score matching (PSM) with a caliper 0.2 was conducted to balance potential bias in baseline. The follow-up data were analyzed primarily for change in quality of life and anxiety status.

RESULTS

After PSM, 32 comparable pairs were matched. The baseline data were comparable and postoperative complications were similar between groups. In terms of SF-36 scale, the role physical, bodily pain, role emotional and mental health subscales were no significantly improved in MFS patients over time. At 1 year after discharged, the subscale of mental health and bodily pain were significantly lower in the MFS group than in the non-MFS group. In terms of HADS assessments, the level of anxiety in MFS patients was significantly higher than in non-MFS patients at 1 year after discharged.

CONCLUSIONS

The QoL in young AAAD patients with MFS is lower than those without MFS after surgery. This may be associated with the uncontrollable persistent chronic pain and the uncertainty and concerns for the disease's progression.

Neurotrophic Keratopathy in Marfan Syndrome Patient After Micropulse Transscleral Cyclophotocoagulation: A Call for Risk Stratification

BACKGROUND Micropulse transscleral cyclophotocoagulation is a non-invasive, widely employed procedure that uses diode laser to target the ciliary body to lower the intraocular pressure. Despite its acknowledged efficacy, certain complications are recognized, with neurotrophic keratopathy being a rare yet serious consequence. This report seeks to shed light on a potential high-risk subgroup susceptible to neurotrophic keratopathy, exemplified by our patient with Marfan syndrome, a condition characterized by thin sclera. CASE REPORT Our patient, who was confirmed to have Marfan syndrome with pseudophakic glaucoma, underwent micropulse transscleral cyclophotocoagulation due to high intraocular pressure bilaterally and subsequently quickly manifested neurotrophic keratopathy in both eyes postoperatively. Swift initiation of management involved a comprehensive approach, including topical antibiotics, preservative-free lubrication, medroxyprogesterone acetate 1%, serum balanced salt solution (BSS) 50%, and the application of bandage contact lenses to expedite healing. Fortunately, the left eye demonstrated resolution within 10 days, while the right eye exhibited delayed healing, leading to subsequent scarring. CONCLUSIONS This report highlights the critical importance of recognizing populations predisposed to neurotrophic keratopathy before subjecting them to micropulse transscleral cyclophotocoagulation. Such awareness allows for the fine-tuning of procedural parameters, offering a strategic approach to mitigate the risk of neurotrophic keratopathy development. By further exploring and recognizing potential risk factors, clinicians can enhance patient outcomes and refine the safety profile of micropulse transscleral cyclophotocoagulation.

Postoperative longitudinal refractive changes in children younger than 8 years with ectopia lentis and Marfan syndrome

PURPOSE

To evaluate the postoperative longitudinal refractive changes in children younger than 8 years with ectopia lentis and Marfan syndrome (MFS).

SETTING

Zhongshan ophthalmic center, Guangzhou, China.

DESIGN

Retrospective cohort study.

METHODS

Medical data of patients diagnosed with ectopia lentis and MFS that underwent surgery younger than 8 years were collected. Refractive errors and ocular biometric parameters were collected preoperatively and at each follow-up visit. Patients were stratified into groups according to age at surgery, and only the eye operated on first was selected. Multivariate analysis was performed to determine the association between refractive shift and potential risk factors.

RESULTS

In total, 54 eyes of 54 patients were enrolled. The median age at surgery was 6.21 years (interquartile range [IQR], 5.25 to 6.85), and the median follow-up was 2.0 years (IQR, 1.2 to 2.8 years). At age 8 years, patients demonstrated a median myopic shift ranged from -1.75 diopters (D) (IQR, -2.75 to -1.00 D) for the 4-year-old group to -0.13 D (IQR, -0.50 to -0.06 D) for the 7-year-old group. Multivariate analysis showed that greater myopic shift was associated with younger age at surgery ( P = .004), male sex ( P = .026), and shorter preoperative axis length ( P = .005).

CONCLUSIONS

A tendency toward increasing postoperative myopic was demonstrated in children with ectopia lentis and MFS, with the greatest myopic shift in the younger age groups. If the goal is to reach emmetropia by age 8 years, the immediate postoperative hypermetropic targets should be 1.75 D for age 4 years, 1 D for age 5 years, 0.5 D for age 6 years, and 0 to 0.25 D for age 7 years.

Cervical kyphosis correction in Marfan syndrome: our experience and literature review

BACKGROUND

Spinal deformities are common in Marfan syndrome (MFS). They usually involve the thoraco-lumbar spine but rarely involves the cervical spine. Kyphosis is the common spine deformity of the cervical spine and mandates surgical correction as they are at risk of neurological deterioration since they are refractory to conservative management. Few studies of surgical correction of spine deformity included cervical deformity.

OBJECTIVES

To analyze the challenges faced during surgery, clinical and radiological outcome, and complications following surgical correction for cervical kyphosis in Marfan syndrome.

METHODS

We identified that 5 patients with a diagnosis of MFS with cervical kyphosis who underwent fusion surgery between the years 2010 and 2022 were reviewed, retrospectively. We analyzed the demographic details, radiological parameters, operative variables (blood loss and nuances), perioperative complications, length of stay, clinical and radiological outcome, and complications following fusion surgery for cervical kyphosis in MFS.

RESULTS

The mean age of patients was 16.6 ± 4.72 years (range, 12-23 years). The average kyphotic vertebra involved is 3 ± 0.7 bodies (range 2-4) with 2 patients with thoracic deformity. All patients underwent surgical deformity correction. All patients improved clinically with Nurick grade (pre vs. post: 3.4 vs. 2.2) and mJOA (pre vs. post: 8.2 vs. 12.6). There was significant deformity correction from 37.48° to 9.1°. Mean blood loss encountered was 900 ± 173.2 ml. Perioperative complications: wound complication with CSF leak (1). Late complications: ventilator dependence (1) and junctional kyphosis (1). Mean length of hospital stay was 103 ± 178.9 days. All patients were doing symptomatically better after mean follow-up of 58 ± 28.32 months. One patient is bedridden and hospitalized.

CONCLUSION

Cervical kyphosis is a rare spine deformity in patients with MFS, and they usually present with neurological deterioration mandating surgical correction. Multidisciplinary approach (pediatrics, genetics and cardiology) is required for systematic evaluation of these patients. They should be evaluated with necessary imaging to rule out associated spinal deformity (atlanto-axial subluxation, scoliosis, and intraspinal pathology like ductal ectasia). Our results suggest better surgical outcome in terms of low operative complications with neurologic improvement in MFS patients. These patients require regular follow-up to identify late complications (instrument failure, non-union, and pseudarthrosis).

Uncovering the Hidden World of Aqueous Humor Proteins for Discovery of Biomarkers for Marfan Syndrome

Ectopia lentis is a hallmark of Marfan syndrome (MFS), a genetic connective tissue disorder affecting 1/5000 to 1/10 000 individuals worldwide. Early detection in ophthalmology clinics and timely intervention of cardiovascular complications can be lifesaving. In this study, a modified proteomics workflow with liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based data-independent acquisition (DIA) and field asymmetric ion mobility spectrometry (FAIMS) to profile the proteomes of aqueous humor (AH) and lens tissue from MFS children with ectopia lentis is utilized. Over 2300 and 2938 comparable proteins are identified in AH and the lens capsule, respectively. Functional enrichment analyses uncovered dysregulation of complement and coagulation-related pathways, collagen binding, and cell adhesion in MFS. Through weighted correlation network analysis (WGCNA) and machine learning, distinct modules associated with clinical traits are constructed and a unique biomarker panel (Q14376, Q99972, P02760, Q07507; gene names: GALE, MYOC, AMBP, DPT) is defined. These biomarkers are further validated using advanced parallel reaction monitoring (PRM) in an independent patient cohort. The results provide novel insights into the proteome characterization of ectopia lentis and offer a promising approach for developing a valuable biomarker panel to aid in the early diagnosis of Marfan syndrome via AH proteome.

Quantitative analysis of choriocapillaris flow deficits and choroidal thickness in children with Marfan syndrome

PURPOSE

To evaluate the characteristics and associated factors of choroidal thickness (ChT) and choriocapillaris flow deficit percentage (CC FD%) in children with Marfan syndrome (MFS).

METHODS

This is a cross-sectional study. The ChT of the subfoveal area and other areas 0.5, 1.5, and 2.5 mm away from the fovea were assessed. The CC FD% of quadrant and circular regions with diameters of 0.5, 1.5 and 2.5 mm were assessed with 3×3 mm macular choriocapillaris images. Best-corrected visual acuity (BCVA) and cardiac function factor such as Z score were measured to analyse the associations with ChT and CC FD%.

RESULTS

51 MFS children and 50 healthy controls were enrolled in this study. Compared with the healthy controls, the ChT in the MFS group was thinner in the subfoveal area, temporal 0.5, 1.5 and 2.5 mm (all p<0.001). The CC FD% was higher in circle 0.5, 1.5 and 2.5 mm (all p<0.001). Multivariate regression analysis showed that CC FD% in the circle 2.5 mm when the Z score ≥2 was associated with BCVA (β=9.08 (95% CI 3.96 to 14.20); p=0.005) and Z score (β=4.19 (95% CI 1.28 to 12.00); p=0.012).

CONCLUSIONS

Thinner ChT and a higher CC FD% were observed in children with MFS, and an increased CC FD% in circle 2.5 mm was significantly associated with worse BCVA and cardiac function. These findings may help identify future visual impairment and early cardiac events in MFS children.

Scattered Media Elastic Fibers from the Aortic Root to the Ascending Aorta in a 30-Year-Old Marfan Syndrome Patient

We present a case report of a 30-year-old Marfan syndrome patient who underwent a David procedure for severe aortic valve insufficiency and Valsalva aneurysm. Harvested aortic walls were examined by pathologists. Although the tunica media of the ascending aorta contained aligned elastic fibers, the aortic root media lacked aligned elastic fibers.

Rare complications of infective endocarditis in marfan-like morphotype: diagnosis of multiple mitral valve aneurysms and aortic root abscess using three-dimensional transesophageal echocardiography

Mitral valve aneurysm (MVA) is characterized by a saccular outpouching of the mitral leaflet, and it represents a rare condition typically associated with aortic valve endocarditis. Three-Dimensional Transesophageal Echocardiography (3D-TEE) serves as an effective tool for detecting the presence of MVA and its potential complications. In this report, we present a case involving a young man with striking images of bicuspid aortic valve endocarditis complicated by an aortic root abscess and multiple perforated mitral valve aneurysms, diagnosed using 3D TEE. This case suggests the uncommon coexistence of Marfan like morphotype, bicuspid aortic valve, and infective endocarditis as a triple mechanism in the occurrence of MVA. It underscores the significance of early and accurate imaging diagnosis for facilitating prompt surgical intervention.

[Secondary non-tuberculous mycobacterium infection in patients with bronchiectasis caused by Marfan syndrome]

In this article, we reported a 28-year-old female patient who presented with intermittent hemoptysis, cough, and sputum production. Laboratory tests showed no abnormalities in the blood counts or inflammatory markers, and the sputum cultures were negative. A chest computed tomography scan showed bronchiectasis associated with infection in the middle and lower lobes of the right lung and right pleural thickening. We performed bronchoalveolar lavage by bronchoscopy in the dorsal segment of the right lower lobe and found Mycobacterium avium intracellulare complex (MAC) by Next Generation Sequencing (NGS) of bronchoalveolar lavage fluid (BALF). The patient's symptoms improved significantly after anti-mycobacterium treatment and the extent of infection was reduced on imaging. To further identify the cause of bronchiectasis, the patient is tall and thin, with slender limbs. Cardiac color ultrasound showed the widening of aortic sinus. Her genetic testing of blood samples revealed the gene mutation in the FBN1 gene (c.4349G>A). Based on these results, she was diagnosed with Marfan syndrome.

[Structural and functional features of the eye in Marfan syndrome. Report 1. Changes in the fibrous tunic of the eye]

Marfan syndrome (MS) is an orphan hereditary connective tissue disease associated with a mutation in the FBN1 gene, which pathological manifestations are characterized by polysystemic involvement. The fibrillin-1 protein is an integral component of the sclera and cornea of the eye, and in MS its structure is distrubed.

PURPOSE

This study assesses potential structural and functional changes in the cornea and sclera of a patient with MS.

MATERIAL AND METHODS

Two groups were formed, comparable in the axial length of the eye and age: the main group - 19 patients (38 eyes) with a verified diagnosis of MS, and the control group - 24 patients (48 eyes) with myopia of varying degrees. The results obtained from MS patients were analyzed depending on the absence or presence of ectopia lentis. In addition to measuring the basic ophthalmological parameters (refraction, axial length, visual acuity), topographic keratometry, anterior segment optical coherence tomography, and ocular response analyzer were used for structural and functional assessment of the cornea and sclera.

RESULTS

In MS there was a statistically significant increase in the radius of curvature and a decrease in corneal refraction in the central zone compared to the control group. There were no significant differences in central corneal thickness, but there was a significant decrease in the thickness of the sclera in the limbal zone compared to the control group. There were no statistically significant changes in corneal hysteresis and corneal resistance factor in MS.

CONCLUSION

This study confirmed the previously obtained data on the tendency of the optical power to reliably decrease in MS (flattening of the cornea). This symptom can be considered as a compensatory factor affecting clinical refraction, while the decrease in the thickness of the sclera - as the main reason for aaxial length elongation in MS. There were no clear patterns of dependence of the changes in the cornea and sclera analyzed in this study on the presence or absence of ectopia lentis. Changes in the lens, perhaps, should be regarded only as one of the potential components of the ocular symptom complex in MS.

Overcoming challenges associated with identifying FBN1 deep intronic variants through whole-genome sequencing

BACKGROUND

Marfan syndrome (MFS), caused by pathogenic variants of FBN1 (fibrillin-1), is a systemic connective tissue disorder with variable phenotypes and treatment responsiveness depending on the variant. However, a significant number of individuals with MFS remain genetically unexplained. In this study, we report novel pathogenic intronic variants in FBN1 in two unrelated families with MFS.

METHODS

We evaluated subjects with suspected MFS from two unrelated families using Sanger sequencing or multiplex ligation-dependent probe amplification of FBN1 and/or panel-based next-generation sequencing. As no pathogenic variants were identified, whole-genome sequencing was performed. Identified variants were analyzed by reverse transcription-PCR and targeted sequencing of FBN1 mRNA harvested from peripheral blood or skin fibroblasts obtained from affected probands.

RESULTS

We found causative deep intronic variants, c.6163+1484A>T and c.5788+36C>A, in FBN1. The splicing analysis revealed an insertion of in-frame or out-of-frame intronic sequences of the FBN1 transcript predicted to alter function of calcium-binding epidermal growth factor protein domain. Family members carrying c.6163+1484A>T had high systemic scores including prominent skeletal features and aortic dissection with lesser aortic dilatation. Family members carrying c.5788+36C>A had more severe aortic root dilatation without aortic dissection. Both families had ectopia lentis.

CONCLUSION

Variable penetrance of the phenotype and negative genetic testing in MFS families should raise the possibility of deep intronic FBN1 variants and the need for additional molecular studies. This study expands the mutation spectrum of FBN1 and points out the importance of intronic sequence analysis and the need for integrative functional studies in MFS diagnosis.

[Structural and functional features of the eye in Marfan syndrome. Report 2. Changes in the anatomical complex of the lens]

Analysis of lens changes in Marfan syndrome (MS), in addition to assessing the position of the lens itself, should include the possibility of examining its supporting and accommodative components (ciliary zonule and ciliary body), or what can be called the entire anatomical complex of the lens. Optical methods of studying the structures of the anterior segment of the eye, due to iris opacity, allow only to analyze the state of the lens within the natural or medically enlarged pupil width. Visualization of the structures located behind the iris is possible with the use of radiation diagnostic methods, in particular ultrasound biomicroscopy (UBM).

PURPOSE

This study assesses the state of the anatomical complex of the lens in MS using UBM.

MATERIAL AND METHODS

The study was carried out on clinical material previously used by us to analyze changes in the fibrous membrane of the eye in MS. At the first stage, the main (19 patients with MS, 38 eyes) and the control (24 patients with myopia, 48 eyes) groups were formed for comparative evaluation. The formed groups were standardized according to the age of the patients and the axial length of the eye. At the second stage, patients with MS were divided into subgroups depending on the absence or presence of biomicroscopic signs of ectopia lentis (22 and 16 eyes, respectively). For UBM, an ultrasound linear sensor with a scanning frequency of 50 MHz was used (Aviso device, Quantel Medical, France). Various biometric UBM indicators were determined: lens thickness, diameter of the lens, lens-axial length factor, iris-lens angle, iris-lens contact distance, posterior chamber depth, length of the fibers of ciliary zonule, thickness of the ciliary body, sclera-ciliary process angle.

RESULTS

There are changes in the anatomical complex of the lens as a whole in MS (in the lens itself, the ciliary zonule, and the ciliary body), which are characterized by an increase in lens thickness and a decrease in the diameter of the lens, an increase in the length of the fibers of the ciliary zonule and a decrease in the thickness of the ciliary body. At the same time, the displacement of the lens detected by optical biomicroscopy (ectopia lentis) can be considered as an advanced stage of changes in the anatomical complex of the lens.

CONCLUSION

UBM provides the possibility of full-fledged visualization of all components of the anatomical complex of the lens in terms of both diagnostics, and monitoring of changes in MS. The question of the advisability of including this method in the algorithm for diagnosing ocular manifestations in order to verify the MS remains open. Possible obstacles may be, on the one hand, related to the need for special and expensive equipment, and on the other hand, the absence of a generally accepted «normal» values of UBM indicators of the anatomical complex of the lens.

Versican accumulation drives Nos2 induction and aortic disease in Marfan syndrome via Akt activation

Thoracic aortic aneurysm and dissection (TAAD) is a life-threatening condition associated with Marfan syndrome (MFS), a disease caused by fibrillin-1 gene mutations. While various conditions causing TAAD exhibit aortic accumulation of the proteoglycans versican (Vcan) and aggrecan (Acan), it is unclear whether these ECM proteins are involved in aortic disease. Here, we find that Vcan, but not Acan, accumulated in Fbn1C1041G/+ aortas, a mouse model of MFS. Vcan haploinsufficiency protected MFS mice against aortic dilation, and its silencing reverted aortic disease by reducing Nos2 protein expression. Our results suggest that Acan is not an essential contributor to MFS aortopathy. We further demonstrate that Vcan triggers Akt activation and that pharmacological Akt pathway inhibition rapidly regresses aortic dilation and Nos2 expression in MFS mice. Analysis of aortic tissue from MFS human patients revealed accumulation of VCAN and elevated pAKT-S473 staining. Together, these findings reveal that Vcan plays a causative role in MFS aortic disease in vivo by inducing Nos2 via Akt activation and identify Akt signaling pathway components as candidate therapeutic targets.

Drug-based cardiovascular prevention in patients with Marfan Syndrome: a systematic review

INTRODUCTION

Marfan Syndrome (MFS) is a rare and complex genetic disorder associated with increased aortic growth and aortic disease. The effectiveness of cardiovascular medical therapies aiming to slow down aortic growth has been tested in several trials, particularly beta-blockers and angiotensin receptor blockers, however showing conflicting results.

EVIDENCE ACQUISITION

We conducted a systematic review on PubMed (Medline), Cochrane library, Google Scholar, and Biomed Central databases between January and February 2022. We selected relevant articles focusing on patients with MFS treated with beta-blockers, angiotensin receptors blockers, or both, and reporting data on the effect of the drugs on 1) slowing down aortic dilatation; 2) the reduction of aortic complication (aortic dissection, mortality, aortic surgery); and with a 3) follow-up length of at least two years. A total of 16 studies were selected.

EVIDENCE SYNTHESIS

Beta-blockers remain the mainstay of therapy as they have proven to slow aortic enlargement. Angiotensin receptor blockers are a useful alternative and with proven benefit as an add-on therapy to limit aortic growth. Neither beta-blockers, nor angiotensin receptor blockers have shown meaningful results on clinical aortic endpoints.

CONCLUSIONS

The current evidence of pharmacological treatment for MFS patients is conflicting due to the lack of large, randomized clinical trials with adequate follow-up studies and homogeneous age grouping. Beta-blockers and angiotensin receptor blockers are the only available treatments to reduce aortic growth. A recently published patient-level meta-analysis confirmed that angiotensin receptor blockers and beta-blockers have a similar effect on reducing the rate of increase of the aortic root Z score, used singularly or as add-on therapy. Considering the current evidence on new features related with MFS (such as mitral annular disjunction - MAD) bearing a potential additional increased arrhythmic risk, it is of paramount importance to establish the role of beta-blockers and angiotensin receptor blockers in clinical endpoints of this population as well.

Comprehensive review of aortic aneurysms, dissections, and cardiovascular complications in connective tissue disorders

Connective tissue disorders, including Marfan syndrome (MS) and Ehlers-Danlos syndrome (EDS), are characterized by genetic mutations affecting connective tissue structural integrity. These disorders significantly elevate the risk of aortic dissection, a life-threatening condition. This comprehensive review delves into the intricate interplay between connective tissue disorders and aortic dissection, shedding light on the clinical features, pathophysiology, genetic underpinnings, diagnostic approaches, clinical management, associated comorbidities, and prognosis, mainly focusing on MS and EDS, while also exploring rare connective tissue disorders and forms of cutis laxa contributing to aortic pathology.

Insights into elastic fiber fragmentation: Mechanisms and treatment of aortic aneurysm in Marfan syndrome

Marfan syndrome (MFS) is an autosomal dominant connective tissue disorder caused by mutations in fibrillin 1 (FBN1) gene. These mutations result in defects in the skeletal, ocular, and cardiovascular systems. Aortic aneurysm is the leading cause of premature mortality in untreated MFS patients. Elastic fiber fragmentation in the aortic vessel wall is a hallmark of MFS-associated aortic aneurysms. FBN1 mutations result in FBN1 fragments that also contribute to elastic fiber fragmentation. Although recent research has advanced our understanding of MFS, the contribution of elastic fiber fragmentation to the pathogenesis of aneurysm formation remains poorly understood. This review provides a comprehensive overview of the molecular mechanisms of elastic fiber fragmentation and its role in the pathogenesis of aortic aneurysm progression. Increased comprehension of elastic fragmentation has significant clinical implications for developing targeted interventions to block aneurysm progression, which would benefit not only individuals with Marfan syndrome but also other patients with aneurysms. Moreover, this review highlights an overlooked connection between inhibiting aneurysm and the restoration of elastic fibers in the vessel wall with various aneurysm inhibitors, including drugs and chemicals. Investigating the underlying molecular mechanisms could uncover innovative therapeutic strategies to inhibit elastin fragmentation and prevent the progression of aneurysms.

Aortic valve reimplantation in patients with connective tissue disorders: Are the leaflets durable?

OBJECTIVE

The durability of reimplanted myxomatous aortic valves in root replacements for patients with connective tissue disorders (CTD) is unclear; therefore, we sought to evaluate the long-term resilience of these repairs.

METHODS

From January 1980 to January 2020, 214 patients with CTD and 645 without CTD underwent primary, elective aortic valve reimplantation operations at Cleveland Clinic. The CTD cohort included 164 (77%) with Marfan, 23 (11%) with Loeys-Dietz, and 7 (3.3%) with Ehlers-Danlos CTD. We accounted for differing patient characteristics between the groups by propensity score matching to compare outcomes, yielding 96 matched pairs. Longitudinal echocardiographic measures were compared using nonlinear mixed effects models.

RESULTS

In the CTD cohort, there were no operative mortalities (30-day or in-hospital), 1 (0.47%) stroke, and 1 (0.47%) early in-hospital reoperation for valve dysfunction. Ten-year prevalence of no aortic regurgitation was 86%, mild 11%, and moderate 3%. Ten-year freedom from reoperation was 97%. In propensity matched cohorts, there were no significant differences in in-hospital outcomes, longitudinal aortic regurgitation and mean gradient, risk of reoperation on the aortic valve, or risk of late death.

CONCLUSIONS

Aortic valve reimplantation is a durable operation in patients with CTD and root aneurysms. These patients do not experience early degeneration of their reimplanted aortic valves.