Fetal Diagnosis of Supravalvular Aortic Stenosis and Pulmonary Stenosis in a Family with Non-Syndromic Elastin Mutation

Supravalvular aortic stenosis (SVAS) has been well described in Williams-Beuren Syndrome and non-syndromic elastin (ELN) mutations. Non-syndromic ELN mutations are inherited in an autosomal dominant pattern with incomplete penetrance and variable expressivity. ELN haploinsufficiency leads to progressive arteriopathy, typically affecting the aortic sinotubular junction. Multi-level pulmonary stenosis has also been reported and biventricular obstruction may portend a worse prognosis. Fetal presentation of ELN mutation with SVAS has not been previously reported in the literature. We present a case of fetal diagnosis of SVAS and multi-level pulmonary stenosis in a family with a known pathogenic ELN mutation (Exon 6, c.278del [p.Pro93Leufs*29]). On the fetus' initial fetal echo, there was only mild flow acceleration through the aortic outflow tract, however, she went on to develop progressive bilateral obstruction. In the early post-natal period, the child was clinically asymptomatic and showed similar mild SVAS and mild valvar and supravalvular pulmonary stenosis. Our case highlights the need for serial monitoring of fetuses with suspected or confirmed ELN arteriopathy.

Numerical study of hemodynamic flow in the aortic vessel of Williams syndrome patient with congenital heart disease

Congenital arterial stenosis such as supravalvar aortic stenosis (SVAS) are highly prevalent in Williams syndrome (WS) and other arteriopathies pose a substantial health risk. Conventional tools for severity assessment, including clinical findings and pressure gradient estimations, often fall short due to their susceptibility to transient physiological changes and disease stage influences. Moreover, in the pediatric population, the severity of these and other congenital heart defects (CHDs) often restricts the applicability of invasive techniques for obtaining crucial physiological data. Conversely, evaluating CHDs and their progression requires a comprehensive understanding of intracardiac blood flow. Current imaging modalities, such as blood speckle imaging (BSI) and four-dimensional magnetic resonance imaging (4D MRI) face limitations in resolving flow data, especially in cases of elevated flow velocities. To address these challenges, we devised a computational framework employing zero-dimensional (0D) lumped parameter models coupled with patient-specific reconstructed geometries pre- and post-surgical intervention to execute computational fluid dynamic (CFD) simulations. This framework facilitates the analysis and visualization of intricate blood flow patterns, offering insights into geometry and flow dynamics alterations impacting cardiac function. In this study, we aim to assess the efficacy of surgical intervention in correcting an extreme aortic defect in a patient with WS, leading to reductions in wall shear stress (WSS), maximum velocity magnitude, pressure drop, and ultimately a decrease in cardiac workload.

Patch aortoplasty for supravalvular aortic stenosis in an adult patient: A case report

INTRODUCTION

Supravalvular aortic stenosis (SVAS) is an uncommon congenital abnormality that presents with intimal thickening of the aortic media at the sinotubular junction. Given the congenital nature of the disease, patients usually become symptomatic in childhood.

PRESENTATION OF CASE

A 48-year-old man developed symptomatic SVAS in middle age. A patch aortoplasty with a bovine pericardial patch was performed. His postoperative course was uneventful, and echocardiography revealed a significant decrease in peak velocity and pressure gradient.

DISCUSSION

SVAS, a congenital heart disease with an incidence of 1 in 20,000 live births, is often linked to Williams syndrome but can also occur independently. Isolated SVAS is generally less severe and may not show symptoms in childhood. Its narrowing often stabilizes after growth, but in this middle-aged patient, symptoms appeared later in life. SVAS usually presents as discrete thickening above the sinuses of Valsalva or as diffuse narrowing along the ascending aorta. Surgical relief is the common treatment, with flap plasty using various patch techniques. This patient, having discrete stenosis and intact aortic valve function, underwent single-patch expansion. Key to this surgery is avoiding coronary artery stenosis, by considering coronary orifice location and other cardiac anomalies. A bovine pericardial patch was chosen for its bleeding control benefits.

CONCLUSION

Although SVAS progression in middle age is quite rare, it can be successfully corrected with detailed and selected surgical procedures.

Coronary artery lesions are associated with adverse cardiac events in children undergoing supravalvular aortic stenosis repair

OBJECTIVES

The aim of this study was to identify the prevalence and anatomic characteristics of coronary artery lesions and their associated postoperative risk in patients undergoing supravalvular aortic stenosis repair.

METHODS

The association between structural risk factors, postoperative ST-segment changes, and major adverse cardiac events was explored using logistic regression and the Fisher's exact test.

RESULTS

In 51 consecutive patients with supravalvular aortic stenosis treated between 2000 and 2017, a total of 48 coronary lesions were identified in 27 patients (53%). Prominent ostial ridge (type I) was the most common coronary lesion, followed by small ostium with (IIIb) or without (IIIa) diffuse long-segment coronary narrowing, and adhesion of the coronary cusp (type II). There were 54 concomitant coronary procedures, including 43 primary corrections and 11 revisions. Thirty-three patients underwent supravalvular aortic stenosis repair with a bifurcated patch, of which 13 (39.4%) had right coronary artery distortion/kinking requiring patch plication (n = 8) and reimplantation (n = 5). Postoperative major adverse cardiac events (MACE) occurred in 9 patients (17.6%), including 3 deaths, 4 needing mechanical circulatory support, and 6 experiencing ventricular arrhythmias. Twenty-two patients (43.1%) had postoperative ST-segment changes, including 13 early changes that resolved within 24 h and 9 persistent changes lasting >24 h. Patients with type III lesions were associated with postoperative persistent ST-segment change (P = 0.04) and these lesions independently predicted postoperative MACE (P = 0.02). Patients with pre-existing coronary lesions were at elevated risk of right coronary artery distortion/kinking (P = 0.045).

CONCLUSIONS

The prevalence of ST-segment changes and MACE is high in patients undergoing supravalvular aortic stenosis repair. The preoperative presence of complex coronary lesions is the most important predictor for postoperative major adverse cardiac events.

Fatal cardiac dysfunction in a child with Williams syndrome

Williams syndrome (WS) is a rare genetic disorder caused by a microdeletion of chromosome 7q11.23. Although the mortality rate of patients with WS is not very high, sudden cardiac death can occur, particularly in cases complicated by coronary artery stenosis. A 3-month-old female infant with supravalvular aortic stenosis and peripheral pulmonary stenosis was discovered unconscious in bed by her mother. She was immediately transferred to an emergency hospital but succumbed despite multiple attempts as resuscitation. DNA microarray analysis revealed microdeletions of 7q11.23 and 16p11.2, confirming WS and unexpectedly identifying 16p11.2 deletion syndrome which is known to be associated with neurodevelopmental disorders. Postmortem computed tomography revealed a severely enlarged heart, indicative of cardiac dysfunction. External examination revealed moderate-to-severe developmental delays in height and body weight. The heart, on internal examination, revealed whitish-discolored lesions; histologically severe fibrotic changes and thickening of the intima in the coronary arteries and aorta. In the brain, the dentate gyrus of the hippocampus appeared malformed. Taken together, these findings suggest that the cause of death was cardiac dysfunction due to WS. In addition, it could be possible that 16p11.2 deletion syndrome and dentate gyrus malformation contributed to her death. Future autopsy studies are warranted to clarify the precise role of microdeletion disorders in sudden death to reduce future preventable deaths in children.

Long-term surgical outcomes of congenital supravalvular aortic stenosis: a systematic review, meta-analysis and microsimulation study

OBJECTIVES

Congenital supravalvular aortic stenosis (SVAS) is a rare form of congenital outflow tract obstruction and long-term outcomes are scarcely reported. This study aims to provide an overview of outcomes after surgical repair for congenital SVAS.

METHODS

A systematic review of published literature was conducted, including observational studies reporting long-term clinical outcome (>2 years) after SVAS repair in children or adults considering >20 patients. Early risks, late event rates and time-to-event data were pooled and entered into a microsimulation model to estimate 30-year outcomes. Life expectancy was compared to the age-, sex- and origin-matched general population.

RESULTS

Twenty-three publications were included, encompassing a total of 1472 patients (13 125 patient-years; pooled mean follow-up: 9.0 (6.2) years; median follow-up: 6.3 years). Pooled mean age at surgical repair was 4.7 (5.8) years and the most commonly used surgical technique was the single-patch repair (43.6%). Pooled early mortality was 4.2% (95% confidence interval: 3.2-5.5%) and late mortality was 0.61% (95% CI: 0.45-0.83) per patient-year. Based on microsimulation, over a 30-year time horizon, it was estimated that an average patient with SVAS repair (mean age: 4.7 years) had an observed life expectancy that was 90.7% (95% credible interval: 90.0-91.6%) of expected life expectancy in the matched general population. The microsimulation-based 30-year risk of myocardial infarction was 8.1% (95% credible interval: 7.3-9.9%) and reintervention 31.3% (95% credible interval: 29.6-33.4%), of which 27.2% (95% credible interval: 25.8-29.1) due to repair dysfunction.

CONCLUSIONS

After surgical repair for SVAS, 30-year survival is lower than the matched-general-population survival and the lifetime risk of reintervention is considerable. Therefore, lifelong monitoring of the cardiovascular system and in particular residual stenosis and coronary obstruction is recommended.

Novel mutation in ELN gene causes cardiac abnormalities and inguinal hernia: case report

BACKGROUND

Elastin-driven genetic diseases are a group of complex diseases driven by elastin protein insufficiency and dominant-negative production of aberrant protein, including supravalvular aortic stenosis (SVAS) and autosomal dominant cutis laxa. Here, a Chinese boy with a novel nonsense mutation in the ELN gene is reported.

CASE PRESENTATION

We report a 1-year-old boy who presented with exercise intolerance, weight growth restriction with age, a 1-year history of heart murmur, and inguinal hernia. Gene sequencing revealed a novel nonsense mutation in the ELN gene (c.757 C > T (p.Gln253Ter), NM_000501.4). Due to severe branch pulmonary artery stenosis, the reconstruction of the branch pulmonary artery with autologous pericardium was performed. The inguinal hernia repair was performed 3 months postoperatively. After six months of outpatient follow-up, the child recovered well, gained weight with age, and had no special clinical symptoms.

CONCLUSION

We identified a de novo nonsense mutation in the ELN gene leading to mild SVAS and severe branch pulmonary artery stenosis. A new phenotype of inguinal hernia was also needed to be considered for possible association with the ELN gene. Still, further confirmation will be necessary.

A new mouse model of elastin haploinsufficiency highlights the importance of elastin to vascular development and blood pressure regulation

Supravalvular aortic stenosis (SVAS) is an autosomal dominant disease resulting from elastin (ELN) haploinsufficiency. Individuals with SVAS typically develop a thickened arterial media with an increased number of elastic lamellae and smooth muscle cell (SMC) layers and stenosis superior to the aortic valve. A mouse model of SVAS (Eln+/-) was generated that recapitulates many aspects of the human disease, including increased medial SMC layers and elastic lamellae, large artery stiffness, and hypertension. The vascular changes in these mice were thought to be responsible for the hypertension phenotype. However, a renin gene (Ren) duplication in the original 129/Sv genetic background and carried through numerous strain backcrosses raised the possibility of renin-mediated effects on blood pressure. To exclude excess renin activity as a disease modifier, we utilized the Cre-LoxP system to rederive Eln hemizygous mice on a pure C57BL/6 background (Sox2-Cre;Elnf/f). Here we show that Sox2-Cre;Eln+/f mice, with a single Ren1 gene and normal renin levels, phenocopy the original global knockout line. Characteristic traits include an increased number of elastic lamellae and SMC layers, stiff elastic arteries, and systolic hypertension with widened pulse pressure. Importantly, small resistance arteries of Sox2-Cre;Eln+/f mice exhibit a significant change in endothelial cell function and hypercontractility to angiotensin II, findings that point to pathway-specific alterations in resistance arteries that contribute to the hypertensive phenotype. These data confirm that the cardiovascular changes, particularly systolic hypertension, seen in Eln+/- mice are due to Eln hemizygosity rather than Ren duplication.

Role of Transthoracic Echocardiography in Early Diagnosis of Williams Syndrome in the Neonatal Period

•

Williams syndrome with SVAS can develop rapidly.

•

Diagnosis of WS based on facial features is difficult in neonates.

•

TTE plays an important role in the assessment of WS in neonates.

Influence of Surgical Methods on Hemodynamics in Supravalvular Aortic Stenosis: A Computational Hemodynamic Analysis

We compared differences in the hemodynamic parameters of multiple surgical techniques for supravalvular aortic stenosis (SVAS). A three-dimensional model was reconstructed based on a patient's CT scan. Virtual McGoon, Doty, and Brom repairs were completed using computer-aided design (CAD). Hemodynamic parameters were calculated through computational fluid dynamics (CFD). The velocity profile and wall shear stress (WSS) showed the blood flow pattern. Energy loss (EL) and energy efficiency (EE) were calculated to estimate the cardiac workload. The perioperative blood flow ratio (BFR) of brachiocephalic vessels and coronary arteries was calculated. The preoperative flow velocity was abnormally high (> 5.0 m/s). High WSS was detected at the sinotubular junction (STJ), and its preoperative distribution in the aorta was uneven. High-speed flow disappeared after each of the three operations. The WSS distribution at the aortic root was consistent with the postoperative STJ structure of each operation. EL in the systolic phase decreased postoperatively (Original: 634 mW, McGoon: 218 mW, Doty: 278 mW, Brom: 255 mW). No significant difference in brachiocephalic BFR was detected among the different techniques. A slightly increased coronary BFR (Original: 7.56%, McGoon: 7.99%, Doty: 8.55%, Brom: 8.89%) was detected. McGoon, Doty, and Brom repair each effectively restored stable blood flow and greatly improved EE. The best WSS distribution and coronary blood supply were achieved after Brom repair due to its ability to reconstruct the symmetrical aortic root structure. CFD combined with a virtual operation is a promising method in surgical planning and optimization for SVAS.

Comparison of Doty and McGoon techniques for surgical reconstruction of congenital supravalvular aortic stenosis

BACKGROUND

We aimed to compare the results of two surgical methods for the treatment of congenital supravalvular aortic stenosis.

METHODS

From May 2004 to January 2020, 29 patients underwent surgical repair for supravalvular aportic stenosis in a single centre. The perioperative evaluation of the patients was retrospectively reviewed.

RESULTS

Fifteen (51.7%) and 14 (48.2%) patients were treated with the Doty and the McGoon methods, respectively. The median age of our cohort was 4.5 (3.0-9.9) years. Ten (34.5%) patients had Williams-Beuren syndrome, and pulmonary stenosis was observed in 12 (41.3%) patients. The median follow-up time was 2.5 (0.7-7.3) years. On follow-up, five patients had residual stenosis with the McGoon technique and one with the Doty technique (p = 0.05). One patient died early in the post-operative period in the Doty group, and three patients were re-operated on due to restenosis in the McGoon group. Freedom from re-operation in the Doty group at 1, 3, 5, and 10 years was 100%. In the McGoon group, freedom from re-operation rates at the 1-, 3-, and 7-year follow-up were 100, 88.9, and 44.4%, respectively (p = 0.08).

CONCLUSION

Our results with both surgical techniques suggest that supravalvular aortic stenosis can be treated with good results. The Doty method provided better relief for the supravalvular aortic segment, considering the residual stenosis and the re-operation rates.

Supravalvular aortic stenosis repair: surgical training of 2 repair techniques using 3D-printed models

There are a number of techniques used in the surgical treatment of supravalvular aortic stenosis with excellent results; however, junior surgeons' experience may be limited due to its rare nature. Simulation with 3D-printed models provides a safe platform for surgeons to rehearse surgical techniques prior to patient application but must replicate all features of surgical anatomy. Here, we describe how software manipulation can be used to accurately reproduce the surgical anatomy in supravalvular aortic stenosis and be used to train surgeons in 2 different techniques.

Midterm Results and Predictors for the Postoperative Vascular Stenosis of Supravalvular Aortic Stenosis

This study reviewed the midterm outcomes of supravalvular aortic stenosis (SVAS) repair and determined the risk factors associated with postoperative aortic or pulmonary stenosis. We retrospectively reviewed 225 patients who underwent surgical correction of SVAS from 2010 to 2019. A total of 178 (79.1%), 44 (19.6%) and 3 (1.3%) patients underwent McGoon, Doty, and Brom repair, respectively. The median age at surgery was 2.2 years (interquartile range, 1.2-4.4). The median follow-up time was 3.7 years (interquartile range, 1.9-5.7). Early and late mortality rates were 3.1% and 1.4%, respectively. The overall 5-year survival rate was 97.9%. Eleven patients received reintervention, including 6 (2.8%) reoperations and 5 (2.3%) balloon dilatations. Higher preoperative pressure gradient at the distal ascending aorta or aortic arch was a risk factor for reintervention (P = 0.04). Rates of mortality and complications were not related to the surgical technique. Eleven patients (5.2%) developed sinotubular junction (STJ) stenosis. Freedom from postoperative distal artery stenosis (DAS) of type II SVAS was significantly lower than that of type I (P < 0.01). Higher preoperative pressure gradient at the STJ (P < 0.01) and concomitant bilateral or peripheral pulmonary artery (PA) stenosis (P < 0.01) were risk factors for postoperative DAS. Postoperative PA stenosis occurred more frequently in patients who received bilateral pulmonary arterioplasty (P < 0.01). Postoperative prognosis of the aortic root after SVAS repair was satisfactory. DAS and PA stenosis were common. The results of bilateral pulmonary arterioplasty were unsatisfactory. The surgical timing and technique for PA stenosis should be carefully considered.

Numerical analysis of stenoses severity and aortic wall mechanics in patients with supravalvular aortic stenosis

Supravalvular aortic stenosis (SVAS) is an aortic malformation characterized by a narrowing of the ascending aorta, resulting in abnormal hemodynamics and pressure drop across the stenosed region. It has been observed that the pressure drops measured from Doppler ultrasound exams often tend to be higher than those obtained from invasive cardiac catheterization. These misleadingly elevated pressure measurements may drive the decision to refer patients for surgical treatment prematurely. Considering this strong clinical association, the purpose of this work is to develop a computational modeling approach using a two-way coupled fluid-structure interaction methodology to determine an accurate prediction of trans-stenotic pressure drop and to further highlight the discrepancy between the SVAS assessment methods. Blood is modeled using Navier-Stokes equations while the aortic wall is simulated by a composite poroelastic structure to represent the three main layers of the arterial wall. The relationship between aortic wall elasticity and the blood flow conditions is examined in varying levels of stenosis, ranging from mild to severe degrees of vessel diameter narrowing. A substantial overestimation of the traditional Doppler pressure drop measurement is observed, especially for severe stenosis levels. The simulation results indicate that elasticity of the aortic wall has a relatively little effect on trans-stenotic pressure drop for the range of mild to moderate SVAS cases, but predicted to have a profound effect for severe SVAS cases. Moreover, significant sensitivity to the pressure drop across the SVAS region from stenosis severity is observed.

Computerized virtual surgery based on computational fluid dynamics simulation for planning coronary revascularization with aortic root replacement in adult congenital heart disease: a case report

A 38-year-old woman presented with exertional dyspnea and chest compression. She had undergone repair of congenital supravalvular aortic stenosis at 8 years of age. Contrast-enhanced computed tomography showed re-stenosis in the ascending aorta, bilateral coronary arterial aneurysm, and a highly thickened left ventricular wall. Release of stenosis was necessary to avoid left ventricular functional deterioration; however, it could cause demand–supply mismatch in coronary flow due to substantial left ventricular hypertrophy. Sufficient statistical evidence was not available in this situation; therefore, computerized virtual surgery based on computational fluid dynamics (CFD) was performed to predict the postoperative hemodynamics. Consequently, root replacement with in situ Carrel patch coronary reconstruction was considered a better option than coronary artery graft bypass in the left-side coronary flow supply. The patient underwent root replacement with in situ Carrel patch coronary reconstruction as planned based on CFD without any complication and was discharged 15 days postoperatively.

An unusual combination of an atypical maternally inherited novel 0.3 Mb deletion in Williams-Beuren region and a de novo 22q11.21 microduplication in an infant with supravalvular aortic stenosis

Williams-Beuren syndrome (WBS) is a rare neurodevelopmental disorder characterized by supravalvular aortic stenosis (SVAS), intellectual disability, overfriendliness and dysmorphic features. It is typically caused by 1.5-1.8 Mb deletions on 7q11.23. The 22q11.21 microduplication syndrome has a variable phenotype and is frequently associated with congenital heart disease. Here we present a unique patient, carrying aberrations within both of the above syndrome regions, referred for possible diagnosis of WBS because of SVAS. The patient was a boy who died suddenly 47 days after birth, possibly due to cardiac complications. Genetic testing was carried out, including array Comparative Genomic Hybridization (aCGH), Fluorescence In situ Hybridization (FISH) and Multiplex Ligation-Dependent Probe Amplification (MLPA) showing that the proband was heterozygous for a novel and atypical 0.3 Mb deletion in WBS region (7q11.23) encompassing the ELN gene. In addition, he was found heterozygous for a 22q11.21 microduplication. Parental studies revealed that the 7q11.23 deletion was inherited from the mother who also exhibited a cardiovascular phenotype, however very mild. The same maternally inherited deletion was detected in one of the proband's siblings, born two years later with a less severe SVAS. The 22q11.2 microduplication was de novo in origin. Detection and investigation of atypical deletions within known syndrome regions are crucial for better genotype-phenotype correlations and more accurate characterization of critical regions. The combined effect of two different genetic defects - one in a known syndrome region and one with variable clinical significance, is valuable for revealing gene interactions and enabling more accurate predictions, especially in prenatal diagnosis.

Successful pharmacological management of a child with compound heterozygous familial hypercholesterolemia and review of the recent literature

Severe familial hypercholesterolemia (SFH) is characterized by markedly elevated low-density lipoprotein cholesterol (LDL-C) and severe early-onset cardiovascular disease if left untreated. We report on the decade-long therapeutic journey of a 15-year-old boy with SFH due to a severe compound heterozygous genotype. He presented at the age of 5 years with widespread xanthomas and LDL-C of 17.4 mmol/L. He was diagnosed with SFH, initially treated with colestyramine that was subsequently combined with simvastatin. At the age of 12 years, he was diagnosed to have supravalvular aortic stenosis and ezetimibe/atorvastatin was introduced in place of colestyramine/simvastatin. At the age of 14 years, he received triple therapy with evolocumab, initially at the recommended dose of 420 mg monthly and then reduced to 140 mg biweekly. Currently at the age of 15 years, he is on atorvastatin 40 mg ON, ezetimibe 10 mg OM, and evolocumab 140 mg biweekly, achieving LDL-C levels of 2.4 mmol/L. Genetic testing identified compound heterozygous mutations in the LDL receptor genes [c.(940 + 1_941-1) (1845 + 1_1846-1)dup] and exon 12, nucleotide c.1747 C > T, amino acid p.(His583Tyr). Medical management without lipoprotein apheresis can achieve target LDL-C in children with SFH. Our patient, who developed supravalvular aortic stenosis at the age of 12 years, needed early aggressive treatment when SFH guidelines and newer drugs for young children were unavailable. Our patient demonstrated that 140 mg biweekly of evolocumab has the same cholesterol-lowering effect as the recommended 420 mg monthly dose.

Cardiovascular abnormalities in patient with Williams-Beuren syndrome

We present a case of a 42-year-old male patient with severe supravalvular aortic stenosis associated with aortic and mitral valve stenosis as well as an anomalous origin of the right coronary ostium caused by deletion in the q11.23 region of the human chromosome 7 in a patient with Williams-Beuren syndrome.

Supravalvular Aortic Stenosis Caused by a Familial Chromosome 7 Inversion Disrupting the ELN Gene Uncovered by Whole-Genome Sequencing

Apparently, balanced chromosomal rearrangements usually have no phenotypic consequences for the carrier. However, in some cases, they may be associated with an abnormal phenotype. We report herein the case of a 4-year-old boy presenting with clinically isolated supravalvular aortic stenosis (SVAS). No chromosomal imbalance was detected by array CGH. The karyotype showed a balanced paracentric chromosome 7 inversion. Breakpoint characterization using paired-end whole-genome sequencing (WGS) revealed an ELN gene disruption in intron 1, accounting for the phenotype. Family study showed that the inversion was inherited, with incomplete penetrance. To our knowledge, this is the first case of a disruption of the ELN gene characterized by WGS. It contributes to refine the genotype-phenotype correlation in ELN disruption. Although this disruption is a rare etiology of SVAS, it cannot be detected by the diagnostic tests usually performed, such as array CGH or sequencing methods (Sanger, panel, or exome sequencing). With the future perspective of WGS as a diagnostic tool, it will be important to include a structural variation analysis in order to detect balanced rearrangements and gene disruption.

Frequent intragenic microdeletions of elastin in familial supravalvular aortic stenosis

BACKGROUND

Supravalvular aortic stenosis (SVAS) is a congenital heart disease affecting approximately 1:25,000 live births. SVAS may occur sporadically, be inherited in an autosomal dominant manner, or be associated with Williams-Beuren syndrome, a complex developmental disorder caused by a microdeletion of chromosome 7q11.23. ELN on 7q11.23, which encodes elastin, is the only known gene to be recurrently mutated in less than half of SVAS patients.

METHODS

Whole-exome sequencing (WES) was performed for seven familial SVAS families to identify other causative gene mutations of SVAS.

RESULTS

Three truncating mutations and three intragenic deletions affecting ELN were identified, yielding a diagnostic efficiency of 6/7 (85%). The deletions, which explained 3/7 of the present cohort, spanned 1-29 exons, which might be missed in the course of mutational analysis targeting point mutations. The presence of such deletions was validated by both WES-based copy number estimation and multiplex ligation-dependent probe amplification analyses, and their pathogenicity was reinforced by co-segregation with clinical presentations.

CONCLUSIONS

The majority of familial SVAS patients appear to carry ELN mutations, which strongly indicates that elastin is the most important causative gene for SVAS. The frequency of intragenic deletions highlights the need for quantitative tests to analyze ELN for efficient genetic diagnosis of SVAS.

Isolated supravalvular aortic stenosis with left ventricular diverticulum and cleft mitral valve: Surgical repair in adulthood

Supravalvular aortic stenosis is an uncommon but well characterized congenital narrowing of the ascending aorta above the level of the coronary arteries. It can be a familial disorder, can occur sporadically, or can be associated with Williams syndrome. We are reporting a very rare presentation of supravalvular aortic stenosis with associated left ventricular diverticulum and cleft mitral valve. Repair consisted of resection of the ascending aorta, patch augmentation of the aortic root, and mitral valve repair. Follow-up echocardiography demonstrated normal mitral and aortic valve function and a postoperative three-dimensional computed tomographic scan showed a normal shape of the reconstructed ascending aorta.

[Reintervention with percutaneous balloon angioplasty in patients with congenital heart disease with left-sided obstructions]

BACKGROUND

Left-sided cardiac obstructions represent 15% of congenital heart disease (CHD). The treatment in adults is surgical; however, balloon dilation by interventional catheterization can alleviate the symptoms in pediatric patients to allow them to reach the target height. The aim was to determine the survival and the factors associated with reintervention in patients with CHD with left-sided obstruction treated with balloon angioplasty.

METHODS

A cohort study was conducted in patients aged 4 to 17 years with left-sided heart obstruction (valvular stenosis [VS], supravalvular aortic stenosis [SAS], coarctation of the aorta [CA]) successfully treated with balloon angioplasty. The follow-up was of 10 years and the outcome variable was the restenosis with reintervention criteria. Pediatric stage at the time of the procedure, nutritional status, residual gradient, and presence of genetic syndromes were considered prognostic variables. For statistical analysis, measures of central tendency and dispersion were used. Chi squared was employed in qualitative variables and Kruskal-Wallis in quantitative variables.

RESULTS

We had a total of 110 patients: 40% had CA, 35% VS, and 25% SAS. 39% required reintervention: 80% in SAS, 35% in CA, and 14% in VS.

CONCLUSION

The intervention balloon is a stopgap measure that allows patients with left-sided obstructions to reach the target height.

Novel ELN mutation in a family with supravalvular aortic stenosis and intracranial aneurysm

Pathogenic germline mutations in ELN can be detected in patients with supravalvular aortic stenosis. The mutation might occur de novo or be inherited following an autosomal dominant pattern of inheritance. In this report we describe a three-generation family suffering from supravalvular aortic stenosis, various other arterial stenoses, sudden death, and intracranial aneurysms. A frameshift mutation in exon 12, not described before, was detected in the affected family members. This report emphasises the importance of family history, genetic counselling, and demonstrates the great variability in the phenotype within a single SVAS family.

Bovine aortic arch with supravalvular aortic stenosis

A 5-year-old boy was diagnosed to have supravalvular aortic stenosis (SVAS). On evaluation of CT angiogram, there was associated bovine aortic arch (BAA). Association of BAA with SVAS has not been previously reported in literature, and to best of our knowledge, this is the first case report of SVAS with BAA. Recent studies show BAA as a marker for aortopathy. SVAS is also an arteriopathy. In light of this, SVAS can also possibly be a manifestation of aortopathy associated with BAA.

Recurrent pulseless electrical activity in a patient with coronary vasospasm and supravalvular aortic stenosis: a case report

BACKGROUND

Pulseless electrical activity cardiac arrest is associated with poor outcomes and the identification of potentially reversible reasons for cardiac arrest is fundamental.

CASE PRESENTATION

We describe the case of a 46-year-old male with the rare coincidental finding of supravalvular aortic stenosis and coronary vasospasm leading to recurrent pulseless electrical activity cardiac arrest. Extracorporeal life support was successfully applied for hemodynamic stabilization. Supravalvular aorticstenosis underwent surgical repair. The patient survived five time resuscitation and was discharged after full neurological recovery.

CONCLUSIONS

Coronary vasospasm and supravalvular aortic stenosis are rare but potentially reversible causes of pulseless electrical activity cardiac arrest. Extracorporeal life support allows accurate diagnostic and possibly therapy even of uncommon reasons for cardiac arrest.

Supravalvular aortic stenosis associated to infectious endocarditis and cerebral vascular disease in a patient with Williams-Beuren Syndrome

The Williams-Beuren syndrome is a rare genetic disease characterized by: (a) typical facial features; (b) psychomotor retardation with a specific neurocognitive profile; (c) cardiovascular condition and (d) likely transient hypocalcemia in infancy. The objective of this study was to describe the clinic evolution and diagnosis of patient with this syndrome that was associated with endocarditis caused by Streptococcus parasanguis in the ascending aorta and an aneurism located in the fronto-temporal area, which produced a parenchymal hematoma in the left lobe, and subarachnoid hemorrhage. He was treated with ceftriaxone and dicloxacillin. Then we proceeded to correct the aneurysm and perform vegetation resection in aortic arteries with supravalvular aortic stenosis correction. The evolution after one year has been favorable and is currently without neurologic sequelae. A 5-year-old male patient presented a diagnosis of supravalvular aortic stenosis. After cardiac catheterization was performed, he presented a fever and right side paresis. The echocardiogram showed multiple vegetations in the ascendant aortic arch and the supraortic arteries. The blood cultures reported S. parasanguis. The magnetic resonance showed a subarachnoid hemorrhage with an aneurysm and a hematoma.

Infective endarteritis in a case of supravalvular aortic stenosis

Supravalvular aortic stenosis is the rarest form of congenital left ventricular outflow tract obstruction. It can be associated with Williams syndrome or it may be an isolated anomaly. Although infective endocarditis is common in valvular aortic stenosis, in supravalvular aortic stenosis infective endocarditis/endarteritis is rarely reported. We report a case of infective endarteritis in a case of supravalvular aortic stenosis due to resistant enterococci, causing prolonged fever. Blood culture-directed antibiotic therapy cured the infection. <Learning objective: Infective endarteritis in supravalvular aortic stenosis is a rarely reported but treatable entity. Although it may respond to empirical antibiotics, occasionally some resistant organism, causing infective endarteritis, may not respond to empirical therapy. Multiple blood culture with culture-directed antibiotic administration may be lifesaving, as in our index case.>.

Surgical treatment of valvular and supravalvular aortic stenosis in homozygous familial hypercholesterolemia

A 61-year-old male with homozygous familial hypercholesterolemia presented with dyspnea and syncope. He had been treated with low-density lipoprotein apheresis for 26 years. Echocardiography and computed tomography showed severe valvular and supravalvular aortic stenosis. Computed tomography and cardiac catheterization revealed a severely calcified narrowed aortic root and an occlusion in the proximal right coronary artery. During surgery, the ascending aorta was replaced under deep hypothermic circulatory arrest without aortic cross-clamping. After that, the aortic root from the annulus to the sino-tubular junction was enlarged with a two-ply bovine pericardial patch. An aortic valve replacement with a 17 mm mechanical valve and coronary artery bypass grafting to the right coronary artery were performed. The patient recovered from the surgery without any cerebrovascular complications.

Cardiovascular manifestations of Williams syndrome: imaging findings

Williams syndrome is a relatively common (1 in 10,000 live births) genetic disorder caused by a deletion involving chromosome 7 that results in a variety of clinically significant abnormalities, including developmental delay, behavioral changes, hypercalcemia, and a distinct "elfin" facial appearance. Congenital cardiovascular disease that presents in childhood is responsible for most of the morbidity and mortality associated with this disorder. The purpose of this pictorial essay is to review imaging findings of some of the more common cardiovascular manifestations of Williams syndrome and to highlight some of the unique anatomic variations that can be seen in these patients.

Mid-term outcome after surgical repair of congenital supravalvular aortic stenosis by extended aortoplasty

OBJECTIVES

Congenital supravalvular aortic stenosis (SVAS) is a rare arteriopathy associated with the Williams-Beuren syndrome (WBS) and other elastin gene deletions. Our objective was to review the mid-term outcomes of SVAS repair with extended aortoplasty.

METHODS

Congenital SVAS repairs from 2001 to 2010 were retrospectively reviewed. The follow-up records, reintervention and reoperation data and most recent echocardiograms were obtained.

RESULTS

From 2001 to 2010, 21 patients (15 males) underwent surgical repair of SVAS by extended aortoplasty with autologous pretreated pericardium, which is a modification of the Doty technique. The mean age was 3.1 ± 4.2 years. WBS was diagnosed in 14 of the patients. There was no early mortality, but one late death was observed. At the latest follow-up (mean follow-up, 4.3 ± 2.9 years; range, 1-108 months), echocardiograms revealed a peak Doppler gradient across the aortic outflow tract of 15 ± 8 mmHg. The majority of the patients had minimal to mild aortic insufficiency. No reoperation or reintervention was required.

CONCLUSIONS

Extended aortoplasty provides excellent mid-term relief of SVAS and, in addition, reshapes the aortic root geometry to a much more favourable anatomical configuration. It can be performed without any increase in operative risks. The mid-term results are excellent.

Supravalvular aortic stenosis in William's syndrome

We report supravalvular aortic stenosis in a 12 year old patient who presented with mental retardation, malformed teeth, broad lower lips, pectus carinatum, clinodactyly, kyphoscoliosis with symptoms of shortness of breath. On examination presence of better volume pulse in right radial artery with ejection systolic murmur best heard in right 2^nd intercostal space were noted. Patient was diagnosed as having William's syndrome with investigations demonstrating Supravalvular aortic stenosis with a gradient of 170 mm Hg.