Thoracoabdominal aortic replacement in a 6-year-old boy with Loeys-Dietz syndrome.

Connective tissue disorders such as Marfan- and Loeys-Dietz syndrome (LDS) can lead to aortic aneurysms and aortic dissections in children. Patients with LDS often necessitating multiple aortic surgeries throughout their lives to extend their lifespan. A boy with LDS underwent Bentall procedure at the age of three for aortic aneurysm. At the age of six, this boy was referred to the hospital again due to severe abdominal pain. Computed tomographic angiography (CTA)indicates aortic dissection (DeBakey Type III, Stanford Type B). After a multidisciplinary team discussion, a successful thoracoabdominal aortic replacement was performed.

Engineered vascular grafts lend unique insight to pathophysiology of aortic aneurysms.

Yang et al.1 generate tissue engineered blood vessels from hiPSC-derived smooth muscle cells harboring a mutation found in Loeys-Dietz syndrome. In vitro and in vivo data from these vessels provide new insight into the molecular physiology of aortic aneurysms and may create a paradigm for understanding a suite of vascular diseases.

Delayed diagnosis of Loeys-Dietz syndrome revealed through atrial septal defect with pulmonary artery dilation.

Loeys-Dietz syndrome (LDS) is an autosomal-dominant connective tissue disorder associated with mutations in the transforming growth factor ß receptor. It is characterized by distinctive craniofacial changes, skeletal features, and cardiovascular complications. We present a case of a 24-year-old male with development delay and a one-year history of progressively worsening dyspnea on moderate exertion and orthopnea. Echocardiography revealed right atrial and right ventricle dilation, right ventricle hypertrophy, atrial septal defect, and aneurysmal dilation of the pulmonary artery trunk. This case underscores the importance of early detection and comprehensive imaging in patients suspected of having LDS, particularly considering the potential for atypical vascular manifestations.

Validating a Curvature-Based Marker of Cervical Carotid Tortuosity for Risk Assessment in Heritable Aortopathies.

BACKGROUND: Cervical arterial tortuosity is associated with adverse outcomes in Loeys-Dietz syndrome and other heritable aortopathies. METHODS AND RESULTS: A method to assess tortuosity based on curvature of the vessel centerline in 3-dimensional space was developed. We measured cervical carotid tortuosity in 65 patients with Loeys-Dietz syndrome from baseline computed tomography angiogram/magnetic resonance angiogram and all serial images during follow-up. Relations between baseline carotid tortuosity, age, aortic root diameter, and its change over time were compared. Patients with unoperated aortic roots were assessed for clinical end point (type A aortic dissection or aortic root surgery during 4 years of follow-up). Logistic regression was performed to assess the likelihood of clinical end point according to baseline carotid tortuosity. Total absolute curvature at baseline was 11.13±5.76 and was relatively unchanged at 8 to 10 years (fold change: 0.026±0.298, P=1.00), whereas tortuosity index at baseline was 0.262±0.131, with greater variability at 8 to 10 years (fold change: 0.302±0.656, P=0.818). Baseline total absolute curvature correlated with aortic root diameter (r=0.456, P=0.004) and was independently associated with aortic events during the 4-year follow-up (adjusted odds ratio [OR], 2.64 [95% CI, 1.02-6.85]). Baseline tortuosity index correlated with age (r=0.532, P<0.001) and was not associated with events (adjusted OR, 1.88 [95% CI, 0.79-4.51]). Finally, baseline total absolute curvature had good discrimination of 4-year outcomes (area under the curve=0.724, P=0.014), which may be prognostic or predictive. CONCLUSIONS: Here we introduce cervical carotid tortuosity as a promising quantitative biomarker with validated, standardized characteristics. Specifically, we recommend the adoption of a curvature-based measure, total absolute curvature, for early detection or monitoring of disease progression in Loeys-Dietz syndrome.

National registry insights on genetic aortopathies and thoracic endovascular aortic interventions.

OBJECTIVE: Thoracic endovascular aortic repair (TEVAR) in patients with genetic aortopathies (GA) is controversial, given concerns of durability. We describe characteristics and outcomes after TEVAR in patients with GA. METHODS: All patients undergoing TEVAR between 2010 and 2023 in the Vascular Quality Iniatitive were identified and categorized as having a GA or not. Demographics, baseline, and procedural characteristics were compared among groups. Multivariable logistic regression was used to evaluate the independent association of GA with postoperative outcomes. Kaplan-Meier methods and multivariable Cox regression analyses were used to evaluate 5-year survival and 2-year reinterventions. RESULTS: Of 19,340 patients, 304 (1.6%) had GA (87% Marfan syndrome, 9% Loeys-Dietz syndrome, and 4% vascular Ehlers-Danlos syndrome). Compared with patients without GA, patients with GA were younger (50 years [interquartile range, 37-72 years] vs 70 years [interquartile range, 61-77 years]), more often presented with acute dissection (28% vs 18%), postdissection aneurysm (48% vs 17%), had a symptomatic presentation (50% vs 39%), and were less likely to have degenerative aneurysms (18% vs 47%) or penetrating aortic ulcer (and intramural hematoma) (3% vs 13%) (all P < .001). Patients with GA were more likely to have prior repair of the ascending aorta/arch (open, 56% vs 11% [P < .001]; endovascular, 5.6% vs 2.1% [P = .017]) or the descending thoracic aorta (open, 12% vs 2% [P = .007]; endovascular, 8.2% vs 3.6% [P = .011]). No significant differences were found in prior abdominal suprarenal repairs; however, patients with GA had more prior open infrarenal repairs (5.3% vs 3.2%), but fewer prior endovascular infrarenal repairs (3.3% vs 5.5%) (all P < .05). After adjusting for demographics, comorbidities, and disease characteristics, patients with GA had similar odds of perioperative mortality (4.6% vs 7.0%; adjusted odds ratio [aOR], 1.1; 95% confidence interval [CI], 0.57-1.9; P = .75), any in-hospital complication (26% vs 23%; aOR, 1.24; 95% CI, 0.92-1.6; P = .14), or in-hospital reintervention (13% vs 8.3%; aOR, 1.25; 95% CI, 0.84-1.80; P = .25) compared with patients without GA. However, patients with GA had a higher likelihood of postoperative vasopressors (33% vs 27%; aOR, 1.44; 95% CI, 1.1-1.9; P = .006) and transfusion (25% vs 23%; aOR, 1.39; 95% CI, 1.03-1.9; P = .006). The 2-year reintervention rates were higher in patients with GA (25% vs 13%; adjusted hazard ratio, 1.99; 95% CI, 1.4-2.9; P < .001), but 5-year survival was similar (81% vs 74%; adjusted hazard ratio, 1.02; 95% CI, 0.70-1.50; P = .1). CONCLUSIONS: TEVAR for patients with GA seemed to be safe initially, with similar odds for in-hospital complications, in-hospital reinterventions, and perioperative mortality, as well as similar hazards for 5-year mortality compared with patients without GA. However, patients with GA had higher 2-year reintervention rates. Future studies should assess long-term durability after TEVAR compared with the recommended open repair to appropriately weigh the risks and benefits of endovascular treatment in patients with GA.

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.

Unraveling the genetic collagen connection: clinical and therapeutic insights on genetic connective tissue disorders.

Hereditary connective tissue disorders include more than 200 conditions affecting different organs and tissues, compromising the biological role of the extracellular matrix through interference in the synthesis, development, or secretion of collagen and/or its associated proteins. The clinical phenotype includes multiple signs and symptoms, usually nonspecific but of interest to rheumatologists because of musculoskeletal involvement. The patient´s journey to diagnosis is long, and physicians should include these disorders in their differential diagnoses of diseases with systemic involvement. In this review, insights for the diagnosis and treatment of osteogenesis imperfecta, hypermobility spectrum disorder/Ehlers-Danlos syndrome, Marfan, Loeys-Dietz, and Stickler syndromes are presented.

Cardiovascular and obstetrical outcomes among delivering patients with Marfan or Loeys-Dietz syndrome: a retrospective analysis by hospital delivery setting.

BACKGROUND: Pregnancy is a high-risk time for patients with Marfan syndrome or Loeys-Dietz syndrome because of the risk for cardiovascular complications, including the risk for aortic dissection. Little is known about the differences in obstetrical and cardiac outcomes based on delivery hospital setting (academic or academic-affiliated vs community medical centers). OBJECTIVE: This study aimed to evaluate the obstetrical and cardiac outcomes of patients with Marfan syndrome or Loeys-Dietz syndrome based on delivery hospital setting. STUDY DESIGN: This was a secondary analysis of a retrospective, observational cohort study of singleton pregnancies among patients with a diagnosis of Marfan syndrome or Loeys-Dietz syndrome from 1990 to 2016. Patients were identified through the Marfan Foundation, the Loeys-Dietz Syndrome Foundation, or the Cardiovascular Connective Tissue Clinic at Johns Hopkins Hospital. Data were obtained via self-reported obstetrical history and verified by review of medical records. Nonparametric analyses were performed using Fisher's exact tests and Wilcoxon rank-sum tests. RESULTS: A total of 273 deliveries among patients with Marfan syndrome or Loeys-Dietz syndrome were included in this analysis (Table 1). More patients who had a known diagnosis before delivery of either Marfan syndrome or Loeys-Dietz syndrome delivered at an academic hospital as opposed to a community hospital (78.6% vs 59.9%; P=.001). Patients with Marfan syndrome or Loeys-Dietz syndrome who delivered at academic centers were more likely to have an operative vaginal delivery than those who delivered at community centers (23.7% vs 8.6%; P=.002). When the indications for cesarean delivery were assessed, connective tissue disease was the primary indication for the mode of delivery at community centers when compared with academic centers (55.6% vs 43.5%; P=.02). There were higher rates of cesarean delivery for arrest of labor and/or malpresentation at community hospitals than at academic centers (23.6% vs 5.3%; P=.01). There were no differences between groups in terms of the method of anesthesia used for delivery. Among those with a known diagnosis of Marfan syndrome or Loeys-Dietz syndrome before delivery, there were increased operative vaginal delivery rates at academic hospitals than at community hospitals (27.2% vs 15.1%; P=.03) (Table 2). More patients with an aortic root measuring ≥4 cm before or after pregnancy delivered at academic centers as opposed to community centers (33.0% vs 10.2%; P=.01), but there were no significant differences in the median size of the aortic root during pregnancy or during the postpartum assessment between delivery locations. Cardiovascular complications were rare; 8 patients who delivered at academic centers and 7 patients who delivered at community centers had an aortic dissection either in pregnancy or the postpartum period (P=.79). CONCLUSION: Patients with Marfan syndrome or Loeys-Dietz syndrome and more severe aortic phenotypes were more likely to deliver at academic hospitals. Those who delivered at academic hospitals had higher rates of operative vaginal delivery. Despite lower frequencies of aortic root diameter >4.0 cm, those who delivered at community hospitals had higher rates of cesarean delivery for the indication of Marfan syndrome or Loeys-Dietz syndrome. Optimal delivery management of these patients requires further prospective research.

Pelvic Floor Dysfunction Among Persons With Marfan and Loeys-Dietz Syndrome.

IMPORTANCE: Connective tissue disorders are proposed in the literature to be predisposing risk factors for pelvic floor disorders. Prior data characterizing the prevalence of and symptom burden related to pelvic floor disorders are limited for individuals with Marfan syndrome and are nonexistent for those with Loeys-Dietz syndrome. OBJECTIVE: The objective of this study was to determine the prevalence and severity of symptoms related to pelvic floor disorders among individuals with Marfan syndrome and Loeys-Dietz syndrome using the Pelvic Floor Distress Inventory-20 (PFDI-20). STUDY DESIGN: In this cross-sectional study, a survey including the PFDI-20 was administered to biologically female individuals older than 18 years with a confirmed diagnosis of Marfan syndrome or Loeys-Dietz Syndrome. Respondents were solicited through the websites, email lists, and social media forums of The Marfan Foundation and The Loeys-Dietz syndrome Foundation. RESULTS: A total of 286 respondents were included in the final analysis, 213 with Marfan syndrome and 73 with Loeys-Dietz syndrome. The median PFDI-20 score of the cohort was 43.8. Individuals with Loeys-Dietz syndrome had higher PFDI-20 scores and were more likely to have established risk factors for pelvic floor disorders that correlated with their PFDI-20 scores compared with those with Marfan syndrome. CONCLUSIONS: Respondents with Marfan syndrome and Loeys-Dietz syndrome experience a high burden of symptoms related to pelvic floor disorders. Despite the similar pathophysiology and clinical manifestations of these disorders, there were differences in PFDI-20 responses that may suggest that these diseases differ in the ways they affect the pelvic floor.

Cardiovascular pathology, inheritance and prognosis in a familial cohort of Loeys-Dietz type III.

INTRODUCTION: Loeys-Dietz syndrome (LDS) is a heritable disease that is the result of dysregulation of the transforming growth factor beta (TGFß) pathway. The pathogenic variants associated with the condition are linked to aortic aneurysms and dissections along with other cardiovascular and non-cardiovascular abnormalities. LDS type III is associated with pathogenic variants in the SMAD3 gene responsible for signally in the TGFß pathway. Most of the current knowledge of LDS stems from studies of LDS I and II patient with limited data on large cohorts of LDS III patients. We sought to identify the prevalence and course of cardiovascular diseases in a large familial cohort of LDS III patients and also to compare these findings with a previously described cohort of similar size with the identical pathogenic variant. METHODS: The cohort was identified by systematic genetic screening of a familial cohort identified through a single proband. Data was collected from retrospective chart review of patients identified to be affected by the syndrome. RESULTS: Screening of 97 patients identified 19 patients (16 through genetic testing and 3 through phenotypic screening of untested direct descendants of genetically positive individuals). The prevalence of cardiovascular abnormalities was 84%. There was significant intrafamilial phenotypic variability within the cohort with the predominant cardiovascular abnormality being mitral valve disease followed by aortic disease. 92% of patients >18 years of age had osteoarthritis which is a further hallmark of LDS III. CONCLUSION: LDS III sets itself apart from the more widely studied LDS types I and II cardiovascular phenotypes by presenting later in life and tending to be more strongly associated with mitral valve disease.

Loeys-Dietz syndrome and Goldenhar syndrome unveiled together.

Haemifacial microsomia is an asymmetrical congenital tissue malformation developed from the first and second branchial arches with or without multi-system involvement. Alternatively recognised as Goldenhar syndrome or oculoauriculovertebral spectrum (OAVS), it is an aetiologically heterogeneous group of disorders showing dominant trends in inheritable form.We present a case of a boy in early childhood with concomitant craniofacial features of craniofacial microsomia with Loeys-Dietz syndrome. He had a unilateral hypoplastic face, asymmetrical ear malformations and multiple preauricular tags with epibulbar dermoid (features suggestive of Goldenhar syndrome). On detailed clinical evaluation, he met Beighton's criteria and was diagnosed with arterial tortuosity. Further molecular testing confirmed the diagnosis of Loeys-Dietz syndrome type II.Loeys-Dietz syndrome is characterised by aortic root enlargement or type A dissection with or without other vascular malformations and facial midline defects. Molecular testing is required to establish the diagnosis because of overlapping features with other connective tissue disorders.

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.

Endovascular aortic repair in patients with Marfan and Loeys-Dietz syndrome is safe and durable when employed by a multi-disciplinary aortic team.

OBJECTIVES: The aim of this study was to report on mid-term outcomes after endovascular aortic repair (EVAR) in patients with Marfan (MFS) or Loeys-Dietz (LDS) syndrome. METHODS: We analysed data from 2 European centres of patients with MFS and LDS undergoing EVAR. Patients were analysed based on (i) timing of the procedure (planned versus emergency procedure) and (ii) the nature of the landing zone (safe versus non-safe). The primary end-point was freedom from reintervention. Secondary end-points were freedom from stroke, bleeding and death. RESULTS: A population of 419 patients with MFS (n = 352) or LDS (n = 67) was analysed for the purpose of this study. Thirty-nine patients (9%) underwent EVAR. Indications for thoracic endovascular aortic repair or EVAR were aortic dissection in 13 (33%) patients, aortic aneurysm in 22 (57%) patients and others (intercostal patch aneurysm, penetrating atherosclerotic ulcer, pseudoaneurysm, kinking of frozen elephant trunk (FET)) in 4 (10%) patients. Thoracic endovascular repair was performed in 34 patients, and abdominal endovascular aortic repair was performed in 5 patients. Mean age at 1st thoracic endovascular aortic repair/EVAR was 48.5 ± 15.4 years. Mean follow-up after 1st thoracic endovascular aortic repair/EVAR was 5.9 ± 4.4 years. There was no statistically significant difference in the rate of reinterventions between patients with non-safe landing zone and the patients with safe proximal landing zone (P = 0.609). Furthermore, there was no increased probability for reintervention after planned endovascular intervention compared to emergency procedures (P = 0.916). Mean time to reintervention, either open surgical or endovascular, after planned endovascular intervention was in median 3.9 years (95% confidence interval 2.0-5.9 years) and 2.0 years (95% confidence interval -1.1 to 5.1 years) (P = 0.23) after emergency procedures. CONCLUSIONS: EVAR in patients with MFS and LDS and a safe landing zone is feasible and safe. Endovascular treatment is a viable option when employed by a multi-disciplinary aortic team even if the landing zone is in native tissue.

Functional analysis of cell lines derived from SMAD3-related Loeys-Dietz syndrome patients provides insights into genotype-phenotype relation.

RATIONALE: Pathogenic (P)/likely pathogenic (LP) SMAD3 variants cause Loeys-Dietz syndrome type 3 (LDS3), which is characterized by arterial aneurysms, dissections and tortuosity throughout the vascular system combined with osteoarthritis. OBJECTIVES: Investigate the impact of P/LP SMAD3 variants with functional tests on patient-derived fibroblasts and vascular smooth muscle cells (VSMCs), to optimize interpretation of SMAD3 variants. METHODS: A retrospective analysis on clinical data from individuals with a P/LP SMAD3 variant and functional analyses on SMAD3 patient-derived VSMCs and SMAD3 patient-derived fibroblasts, differentiated into myofibroblasts. RESULTS: Individuals with dominant negative (DN) SMAD3 variant in the MH2 domain exhibited more major events (66.7% vs. 44.0%, P = 0.054), occurring at a younger age compared to those with haploinsufficient (HI) variants. The age at first major event was 35.0 years [IQR 29.0-47.0] in individuals with DN variants in MH2, compared to 46.0 years [IQR 40.0-54.0] in those with HI variants (P = 0.065). Fibroblasts carrying DN SMAD3 variants displayed reduced differentiation potential, contrasting with increased differentiation potential in HI SMAD3 variant fibroblasts. HI SMAD3 variant VSMCs showed elevated SMA expression and altered expression of alternative MYH11 isoforms. DN SMAD3 variant myofibroblasts demonstrated reduced extracellular matrix formation compared to control cell lines. CONCLUSION: Distinguishing between P/LP HI and DN SMAD3 variants can be achieved by assessing differentiation potential, and SMA and MYH11 expression. The differences between DN and HI SMAD3 variant fibroblasts and VSMCs potentially contribute to the differences in disease manifestation. Notably, myofibroblast differentiation seems a suitable alternative in vitro test system compared to VSMCs.

The Impact of Pregnancy in Patients with Thoracic Aortic Disease: Epidemiology, Risk Assessment, and Management Considerations.

Thoracic aortic disease (TAD) poses substantial risks during pregnancy, particularly for women with genetic conditions such as Marfan syndrome, Loeys-Dietz syndrome, and vascular Ehlers-Danlos syndrome. This review examines the epidemiology, risk assessment, and management of TAD in pregnancy. Preconception counseling is vital considering the hereditary nature of TAD and potential pregnancy-related complications. Genetic testing and imaging surveillance aid in risk assessment. Medical management, including beta-blockade and strict blood pressure control, is essential throughout pregnancy. Surgical interventions may be necessary in certain cases. A multidisciplinary approach involving cardiologists, obstetricians, cardiac surgeons, anesthesiologists, and other specialists with expertise in cardio-obstetrics is essential for optimal outcomes. Patient education and shared decision-making play vital roles in navigating the complexities of TAD in pregnancy and improving maternal and neonatal outcomes.

Loeys-Dietz syndrome with a novel in-frame SMAD3 deletion diagnosed as a result of postpartum aortic dissection: A case report.

OBJECTIVE: Loeys-Dietz syndrome (LDS) is a rare, autosomal dominant connective tissue disorder which can aggressively affect the aortic vasculature. Limited information is available regarding its impact on pregnancy and postpartum outcomes. CASE REPORT: A pregnant 38-year-old nulliparous woman with mild aortic regurgitation and family history of aortic aneurysms presented with an aortic root measuring 49 mm. Despite concerns of an underlying connective tissue disorder, a definitive diagnosis was not reached. She delivered under strict blood pressure control, developed intractable uterine atony, and underwent uterine artery embolization. On the second postpartum day, aortic dissection was incidentally diagnosed, and aortic root replacement surgery was performed. Genetic testing revealed a novel in-frame SMAD3 deletion [NM_005902.4: c.703_708del, (p.Ile235_Ser236del)], leading to a diagnosis of LDS type 3. CONCLUSION: This case highlights the high postpartum aortic dissection risk in women with LDS, emphasizing the importance of early diagnosis in pregnant women with few clinical symptoms.

Familial visceral branch artery aneurysms in Loeys-Dietz syndrome.

Loeys-Dietz syndrome (LDS) is an autosomal dominant heritable disorder due to pathogenic variants in one of several genes involved in TGF-ß (transforming growth factor-beta) signalling. LDS is associated with aortic aneurysm and dissection. LDS may also lead to extra-aortic aneurysms, the majority of which occur in the head and neck vasculature. Visceral aneurysms are uncommon, and no cases of distal superior mesenteric artery (SMA) branch aneurysms in patients with LDS have been reported. Three related females with TGFBR1-related LDS developed distal SMA branch artery aneurysms involving the ileocolic and jejunal arteries. Endovascular or surgical intervention was performed in each. The presence and severity of arterial, craniofacial, and cutaneous features of LDS in these patients are variable. TGFBR1-related LDS may rarely lead to SMA branch artery aneurysms that can develop later in life. Surgical and endovascular procedures can successfully treat these aneurysms, but data to guide size thresholds and optimal treatment strategies are lacking.