Bicuspid aortic valve is heritable

Retrospective comparison of parent-reported genetics knowledge, empowerment, and familial uptake of cardiac screening between parents who received genetic counseling by a certified genetic counselor and those who did not: A single US academic medical center study

Bicuspid aortic valve (BAV) is the most common congenital heart defect, which can cause severe cardiac complications. BAVs cluster in families and demonstrate high heritability. Cardiac screening for first-degree relatives of individuals with a BAV is recommended. This retrospective two-group study evaluated the impact of cardiovascular genetic counseling provided by a board-certified genetic counselor on parent-reported outcomes by comparing parental responses of those who received genetic counseling by a genetic counselor (GC group) for family history of BAV to those who did not (non-GC group). A retrospective chart review from May 2016 to June 2019 identified 133 pediatric patients with an isolated BAV. Parents of eligible probands were invited to complete an online survey assessing genetics knowledge, empowerment (Genomics Outcome Scale), and familial uptake of cardiac screening. Surveys were completed by 38/97 (39%) parents in the non-GC group and 20/36 (56%) parents in the GC group. The median genetics knowledge score was not significantly different between the two groups (GC group: 8, range 3-11 out of a maximum possible of 12; non-GC group: 7, range 2-11; p = .08). The mean empowerment score was not significantly different between the two groups (GC group: mean 24.6, SD 2.2; non-GC group: mean 23.2, SD 3.5; p = .06). The uptake of cardiac screening was significantly higher in the GC group with 39/59 (66%) total first-degree relatives reported as having been screened compared with 36/91 (40%) in the non-GC group (p = .002). Parent-reported outcomes in our study suggest that receiving genetic counseling by a board-certified genetic counselor significantly increased familial uptake of cardiac screening for first-degree relatives of pediatric patients with a BAV. Studies with larger sample sizes are needed to confirm the findings of this study; however, a referral to a genetic counselor should be considered for patients with a BAV.

Heart Disease and Stroke Statistics-2022 Update: A Report From the American Heart Association

BACKGROUND

The American Heart Association, in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2022 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population and an enhanced focus on social determinants of health, adverse pregnancy outcomes, vascular contributions to brain health, and the global burden of cardiovascular disease and healthy life expectancy.

RESULTS

Each of the chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policymakers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Sex Differences and Similarities in Valvular Heart Disease

As populations age worldwide, the burden of valvular heart disease has grown exponentially, and so has the proportion of affected women. Although rheumatic valve disease is declining in high-income countries, degenerative age-related causes are rising. Calcific aortic stenosis and degenerative mitral regurgitation affect a significant proportion of elderly women, particularly those with comorbidities. Women with valvular heart disease have been underrepresented in many of the landmark studies which form the basis for guideline recommendations. As a consequence, surgical referrals in women have often been delayed, with worse postoperative outcomes compared with men. As described in this review, a more recent effort to include women in research studies and clinical trials has increased our knowledge about sex-based differences in epidemiology, pathophysiology, diagnostic criteria, treatment options, outcomes, and prognosis.

CELSR1 Risk Alleles in Familial Bicuspid Aortic Valve and Hypoplastic Left Heart Syndrome

BACKGROUND

Whole-genome sequencing in families enables deciphering of congenital heart disease causes. A shared genetic basis for familial bicuspid aortic valve (BAV) and hypoplastic left heart syndrome (HLHS) was postulated.

METHODS

Whole-genome sequencing was performed in affected members of 6 multiplex BAV families, an HLHS cohort of 197 probands and 546 relatives, and 813 controls. Data were filtered for rare, predicted-damaging variants that cosegregated with familial BAV and disrupted genes associated with congenital heart disease in humans and mice. Candidate genes were further prioritized by rare variant burden testing in HLHS cases versus controls. Modifier variants in HLHS proband-parent trios were sought to account for the severe developmental phenotype.

RESULTS

In 5 BAV families, missense variants in 6 ontologically diverse genes for structural (SPTBN1, PAXIP1, and FBLN1) and signaling (CELSR1, PLXND1, and NOS3) proteins fulfilled filtering metrics. CELSR1, encoding cadherin epidermal growth factor laminin G seven-pass G-type receptor, was identified as a candidate gene in 2 families and was the only gene demonstrating rare variant enrichment in HLHS probands (P=0.003575). HLHS-associated CELSR1 variants included 16 missense, one splice site, and 3 noncoding variants predicted to disrupt canonical transcription factor binding sites, most of which were inherited from a parent without congenital heart disease. Filtering whole-genome sequencing data for rare, predicted-damaging variants inherited from the other parent revealed 2 cases of CELSR1 compound heterozygosity, one case of CELSR1-CELSR3 synergistic heterozygosity, and 4 cases of CELSR1-MYO15A digenic heterozygosity.

CONCLUSIONS

CELSR1 is a susceptibility gene for familial BAV and HLHS, further implicating planar cell polarity pathway perturbation in congenital heart disease.

Is Bicuspid Aortic Valve Morphology Genetically Determined? A Family-Based Study

Bicuspid aortic valve (BAV) is a common congenital heart disease, with a 10-fold higher prevalence in first-degree relatives. BAV has different phenotypes based on the morphology of cusp fusion. These phenotypes are associated with different clinical courses and prognoses. Currently, the determinants of the valve phenotype are unknown. In this study we evaluated the role of genetics using familial cohorts. Patients with BAV and their first-degree relatives were evaluated by echocardiography. The concordance in BAV phenotype between pairs of family members was calculated and compared with the concordance expected by chance. We then performed a systematic literature review to identify additional reports and calculated the overall concordance rate. During the study period, 70 cases from 31 families and 327 sporadic cases were identified. BAV was diagnosed in 14% of the screened relatives. The proportions of the morphologies identified was: 12.3% for type 0, 66.2% for type 1-LR, 15.4% for type 1-RN, 4.6% for type 1-NL, and 1.5% for type 2. For the assessment of morphologic concordance, we included 120 pairs of first-degree relatives with BAV from our original cohort and the literature review. Concordance was found only in 62% of the pairs which was not significantly higher than expected by chance. In conclusion, our finding demonstrates intrafamilial variability in BAV morphology, suggesting that morphology is determined by factors other than Mendelian genetics. As prognosis differs by morphology, our findings may suggest that clinical outcomes may vary even between first-degree relatives.

Association of Regional Wall Shear Stress and Progressive Ascending Aorta Dilation in Bicuspid Aortic Valve

OBJECTIVES

The aim of this study was to evaluate the role of wall shear stress (WSS) as a predictor of ascending aorta (AAo) growth at 5 years or greater follow-up.

BACKGROUND

Aortic 4-dimensional flow cardiac magnetic resonance (CMR) can quantify regions exposed to high WSS, a known stimulus for arterial wall dysfunction. However, its association with longitudinal changes in aortic dilation in patients with bicuspid aortic valve (BAV) is unknown.

METHODS

This retrospective study identified 72 patients with BAV (age 45 ± 12 years) who underwent CMR for surveillance of aortic dilation at baseline and ≥5 years of follow-up. Four-dimensional flow CMR analysis included the calculation of WSS heat maps to compare regional WSS in individual patients with population averages of healthy age- and sex-matched subjects (database of 136 controls). The relative areas of the AAo and aorta (in %) exposed to elevated WSS (outside the 95% CI of healthy population averages) were quantified.

RESULTS

At a median follow-up duration of 6.0 years, the mean AAo growth rate was 0.24 ± 0.20 mm/y. The fraction of the AAo exposed to elevated WSS at baseline was increased for patients with higher growth rates (>0.24 mm/y, n = 32) compared with those with growth rates <0.24 mm/y (19.9% [IQR: 10.2%-25.5%] vs 5.7% [IQR: 1.5%-21.3%]; P = 0.008). Larger areas of elevated WSS in the AAo and entire aorta were associated with higher rates of AAo dilation >0.24 mm/y (odds ratio: 1.51; 95% CI: 1.05-2.17; P = 0.026 and odds ratio: 1.70; 95% CI: 1.01-3.15; P = 0.046, respectively).

CONCLUSIONS

The area of elevated AAo WSS as assessed by 4-dimensional flow CMR identified BAV patients with higher rates of aortic dilation and thus might determine which patients require closer follow-up.

A novel TBX19 gene mutation in patients with isolated ACTH deficiency from distinct families with a common geographical origin

Isolated ACTH deficiency (IAD) is a life-threatening condition, particularly in the neonatal period, while a main consequence of undiagnosed isolated ACTH deficiency in survivors is cognitive impairment. TBX19 is involved in the differentiation and proliferation of corticotropic cells and TBX19 mutations are responsible for more than 60% of neonatal cases of IAD. We describe a new variant of the main TBX19 transcript (NM 005149.3, c.840del (p.(Glu280Asp fs*27)), classified as pathogenic, whose pathogenicity is assumed to be due to nonsense mediated decay leading to non-expression of T-box transcription factor TBX19. Moreover we summarize the TBX19 mutations published as individual cases since our last large cohort. Interestingly, this pathogenic variant was identified in four patients from three apparently unrelated families. Two of these families were consanguineous, and after investigations all of three were discovered to have roots in the same mountainous region of northern Morocco, suggesting a founder effect. Early diagnosis, timely treatment (hydrocortisone therapy) and preventive education allowed normal development, growth and quality of life in all patients.

Unicuspid aortic valve: a rare congenital anomaly

Unicuspid aortic valve (UAV) is a rare congenital aortic valve anomaly. It has two subtypes and often is associated with aortic valve dysfunction and corresponding clinical presentations. Echocardiography is the first choice of diagnostic method for UAV. Three-dimensional echocardiography has played an increasingly important role in diagnosis, intraprocedural guidance, and post-procedural assessment in recent years. There remain challenges in distinguishing UAV from bicuspid aortic valve (BAV) or tricuspid aortic valve (TAV). Misdiagnosis is most resulted from raphes or leaflet calcifications. Multi-modality imaging has obvious advantages over single-modality imaging and is crucial for UAV diagnosis. Accurate identification of aortic valve morphology is important to choose the best treatment. Aortic balloon valvoplasty, surgical valvotomy, commissurotomy, Ross procedure, surgical valve repair and surgical replacement are most common treatment modalities of UAV. In this review, we aim to discuss UAV including epidemiology, definition, classification, diagnostic importance and necessity, valvular function, clinical presentation, associated disorders, non-invasive diagnostic modalities and therapeutic approaches.

Uptake of Screening and Recurrence of Bicuspid Aortic Valve and Thoracic Aortic Aneurysm Among At-Risk Siblings of Pediatric Probands

OBJECTIVE

To determine uptake of cardiac screening and recurrence of bicuspid aortic valve (BAV) and thoracic aortic aneurysm (TAA) in a population of at-risk siblings of pediatric probands.

STUDY DESIGN

A retrospective chart review of pediatric patients with known BAV and/or TAA was performed. Echocardiogram data from identified siblings were collected to determine screening uptake and recurrence of BAV and TAA. Statistical analyses were performed using Wilcoxon signed-rank test and chi-square.

RESULTS

The cohort included 251 probands and 388 at-risk siblings. Among the siblings, 150 had at least 1 echocardiogram, giving an overall screening uptake of 38.7%. The only factor found to be associated with increased uptake was documented recommendation for screening of first-degree relatives in the proband's initial cardiology note (P = .03). A total of 11 screened siblings (7.3%) had BAV and 19 had TAA (12.7%), with an overall combined recurrence of 15.3%. Siblings of probands who had both BAV and TAA had increased recurrence of TAA compared with siblings of probands with isolated BAV (16.1% vs 3.9%, respectively).

CONCLUSIONS

Given low uptake in at-risk siblings, the opportunity exists to assess barriers for families in pursuing the recommended screening. Furthermore, the relatively high recurrence of BAV and TAA in at-risk siblings highlights the potential for improved health outcomes through increased screening and early detection. Developing standardized guidelines and promoting early cardiac screening in at-risk siblings while counseling families about hereditary risk for BAV and TAA may help improve uptake and optimize clinical management in at-risk pediatric patients.

Phenotypes of Cardiovascular Diseases: Current Status and Future Perspectives

Cardiovascular diseases (CVDs) are a large group of diseases and have become the leading cause of morbidity and mortality worldwide. Although considerable progresses have been made in the diagnosis, treatment and prognosis of CVD, communication barriers between clinicians and researchers still exist because the phenotypes of CVD are complex and diverse in clinical practice and lack of unity. Therefore, it is particularly important to establish a standardized and unified terminology to describe CVD. In recent years, there have been several studies, such as the Human Phenotype Ontology, attempting to provide a standardized description of the disease phenotypes. In the present article, we outline recent advances in the classification of the major types of CVD to retrospectively review the current progresses of phenotypic studies in the cardiovascular field and provide a reference for future cardiovascular research.

Family screening in patients with isolated bicuspid aortic valve : Restriction to those with aortic dilatation is not justified

Aim

To determine the prevalence of undiagnosed bicuspid aortic valve (BAV) and isolated aortic dilatation in first-degree relatives (FDRs) of patients with isolated BAV and to explore the recurrence risk of BAV in different subgroups of probands with BAV. Recent American College of Cardiology (ACC)/American Heart Association (AHA) Guidelines recommend family screening in patients with associated aortopathy only.

Methods

During follow-up visits, patients with isolated BAV received a printed invitation for their FDRs advising cardiac screening.

Results

From 2012–2019, 257 FDRs of 118 adult BAV patients were screened, among whom 63 (53%) index patients had undergone aortic valve surgery (AVS), including concomitant aortic replacement in 25 (21%). Of the non-operated index patients, 31 (26%) had aortic dilatation (> 40 mm). Mean age of the FDRs was 48 years (range 4–83) and 42% were male. The FDR group comprised 20 parents, 103 siblings and 134 offspring. Among these FDRs, 12 (4.7%) had a previously undiagnosed BAV and 23 (8.9%) had an isolated aortic dilatation. FDRs of the probands with previous AVS (n = 147) had a risk ratio for BAV of 2.25 (95% confidence interval (CI) 0.62–8.10). FDRs of the probands with BAV and repaired or unrepaired aortic dilatation (n = 127) had a risk ratio for BAV of 0.51 (95% CI 0.16–1.66).

Conclusion

Screening FDRs of patients with isolated BAV resulted in a reasonable yield of 14% new cases of BAV or isolated aortic dilatation. A trend towards an increased risk of BAV in FDRs was observed in the probands with previous AVS, whereas this risk seemed to be diminished in the probands with associated aortic dilatation. This latter finding does not support the restrictive ACC/AHA recommendation.

Potential role of an athlete-focused echocardiogram in sports eligibility

Sudden cardiac death (SCD) of an athlete is a rare but tragic event and sport activity might play a trigger role in athletes with underlying structural or electrical heart diseases. Preparticipation screenings (PPs) have been conceived for the potential to prevent SCD in young athletes by early identification of cardiac diseases. The European Society of Cardiology protocol for PPs includes history collection, physical examination and baseline electrocardiogram, while further examinations are reserved to individuals with abnormalities at first-line evaluation. Nevertheless, transthoracic echocardiography has been hypothesized to have a primary role in the PPs. This review aims to describe how to approach an athlete-focused echocardiogram, highlighting what is crucial to focus on for the different diseases (cardiomyopathies, valvulopathies, congenital heart disease, myocarditis and pericarditis) and when is needed to pay attention to overlap diagnostic zone ("grey zone") with the athlete's heart. Once properly tested, focused echocardiography by sports medicine physicians may become standard practice in larger screening practices, potentially available during first-line evaluation.

Significance of Hemodynamics Biomarkers, Tissue Biomechanics and Numerical Simulations in the Pathogenesis of Ascending Thoracic Aortic Aneurysms

Guidelines for the treatment of aortic wall diseases are based on measurements of maximum aortic diameter. However, aortic rupture or dissections do occur for small aortic diameters. Growing scientific evidence underlines the importance of biomechanics and hemodynamics in aortic disease development and progression. Wall shear stress (WWS) is an important hemodynamics marker that depends on aortic wall morphology and on the aortic valve function. WSS could be helpful to interpret aortic wall remodeling and define personalized risk criteria. The complementarity of Computational Fluid Dynamics and 4D Magnetic Resonance Imaging as tools for WSS assessment is a promising reality. The potentiality of these innovative technologies will provide maps or atlases of hemodynamics biomarkers to predict aortic tissue dysfunction. Ongoing efforts should focus on the correlation between these non-invasive imaging biomarkers and clinico-pathologic situations for the implementation of personalized medicine in current clinical practice.

Bicuspid Aortic Valve: Genetic and Clinical Insights

Bicuspid aortic valve (BAV) is the most common valvular congenital heart disease, with a prevalence of 0.5 to 2% in the general population. Patients with BAV are at risk for developing cardiovascular complications, some of which are life-threatening. BAV has a wide spectrum of clinical presentations, ranging from silent malformation to severe and even fatal cardiac events. Despite the significant burden on both the patients and the health systems, data are limited regarding pathophysiology, risk factors, and genetics. Family studies indicate that BAV is highly heritable, with autosomal dominant inheritance, incomplete penetrance, variable expressivity, and male predominance. Owing to its complex genetic model, including high genetic heterogenicity, only a few genes were identified in association with BAV, while the majority of BAV genetics remains obscure. Here, we review the different forms of BAV and the current data regarding its genetics. Given the clear heritably of BAV with the potential high impact on clinical outcome, the clinical value and cost effectiveness of cascade screening are discussed.

Common deletion variants causing protocadherin-α deficiency contribute to the complex genetics of BAV and left-sided congenital heart disease

Bicuspid aortic valve (BAV) with ~1%-2% prevalence is the most common congenital heart defect (CHD). It frequently results in valve disease and aorta dilation and is a major cause of adult cardiac surgery. BAV is genetically linked to rare left-heart obstructions (left ventricular outflow tract obstructions [LVOTOs]), including hypoplastic left heart syndrome (HLHS) and coarctation of the aorta (CoA). Mouse and human studies indicate LVOTO is genetically heterogeneous with a complex genetic etiology. Homozygous mutation in the Pcdha protocadherin gene cluster in mice can cause BAV, and also HLHS and other LVOTO phenotypes when accompanied by a second mutation. Here we show two common deletion copy number variants (delCNVs) within the PCDHA gene cluster are associated with LVOTO. Analysis of 1,218 white individuals with LVOTO versus 463 disease-free local control individuals yielded odds ratios (ORs) at 1.47 (95% confidence interval [CI], 1.13-1.92; p = 4.2 × 10-3) for LVOTO, 1.47 (95% CI, 1.10-1.97; p = 0.01) for BAV, 6.13 (95% CI, 2.75-13.7; p = 9.7 × 10-6) for CoA, and 1.49 (95% CI, 1.07-2.08; p = 0.019) for HLHS. Increased OR was observed for all LVOTO phenotypes in homozygous or compound heterozygous PCDHA delCNV genotype comparison versus wild type. Analysis of an independent white cohort (381 affected individuals, 1,352 control individuals) replicated the PCDHA delCNV association with LVOTO. Generalizability of these findings is suggested by similar observations in Black and Chinese individuals with LVOTO. Analysis of Pcdha mutant mice showed reduced PCDHA expression at regions of cell-cell contact in aortic smooth muscle and cushion mesenchyme, suggesting potential mechanisms for BAV pathogenesis and aortopathy. Together, these findings indicate common variants causing PCDHA deficiency play a significant role in the genetic etiology of common and rare LVOTO-CHD.

Cost-effectiveness analysis of screening for first-degree relatives of patients with bicuspid aortic valve

AIMS

Bicuspid aortic valve (BAV) is the commonest congenital heart valve malformation, and is associated with life-threatening complications. Given the high heritability index of BAV, many experts recommend echocardiography screening for first-degree relatives (FDRs) of an index case. Here we aim to evaluate the cost-effectiveness of such cascade screening for BAV.

METHODS

Using a decision-analytic model, we performed a cost-effectiveness analysis of echocardiographic screening for FDRs of BAV index case. Data on BAV probabilities and complications among FDRs were derived from our institution's BAV familial cohort and from the literature on population-based BAV cohorts with long-term follow-up. Health gain was measured as quality-adjusted life years (QALYs). Cost inputs were based on list prices and literature data. One-way and probabilistic sensitivity analyses were performed to account for uncertainty in the model's variables.

RESULTS

Screening of FDRs was found to be the dominant strategy, being more effective and less costly than no screening, with savings of €644 and gains of 0.3 QALYs. Results were sensitive throughout the rang of the model's variables, including the full range of reported BAV rates among FDRs across the literature. A gradual decrease of the incremental effect was found with the increase in screening age.

CONCLUSIONS

This economic evaluation model found that echocardiographic screening of FDRs of BAV index case is not only clinically important but also cost-effective and cost-saving. Sensitivity analysis supported the model's robustness, suggesting its generalization.

Two MicroRNAs, miR-34a and miR-125a, Are Implicated in Bicuspid Aortopathy by Modulating Metalloproteinase 2

It has been recognized that wall shear stress plays an important role in the development of Bicuspid Aortopathy (BA), but the intrinsic mechanism is not well elucidated. This study aims to explore the underlying relationship between hemodynamical forces and pathological phenomenon. Total RNA was prepared from aortic wall tissues collected from 20 BA patients. RNA sequencing, bioinformatic analysis and quantitative reverse-transcription PCR validation identified nine miRNAs that were up-regulated in the aortic part exposed to high wall shear stress compared to the low wall shear stress control, and six miRNAs that were down-regulated. Among these candidates, miR-34a and miR-125a, both down-regulated in the high wall shear stress parts, were shown to be potential inhibitors of the metalloproteinase 2 gene. Luciferase reporter assays confirmed that both miRNAs could inhibit the expression of metalloproteinase 2 mRNA in CRL1999 by complementing with its 3' untranslated region. Conversely, immunofluorescence assays showed that inhibition of miR-34a or miR-125a could lead to increased metalloproteinase 2 protein level. On the other hand, both miR-34a and miR-125a were shown to alleviate stretch-induced stimulation of metalloproteinase 2 expression in CRL1999 cells. The results suggested that miR-34a and miR-125a might be implicated in wall shear stress induced aortic pathogenesis due to their apparent regulatory roles in metalloproteinase 2 expression and extracellular matrix remodeling, which are key events in the weakening of aortic walls among BA patients.

Incidental finding of an adult intracardiac teratoma

We reported an exceedingly rare adult case of intracardiac teratoma with a bicuspid aortic valve. A small mass was discovered in the right ventricle of a 37-year-old man by accident after he was referred to our hospital due to chronic chest distress and aggravated palpitation. We performed a surgical exploration with excision of the lesion after a repeat transthoracic echocardiography suggested a space-occupying lesion in the interventricular septum. A mature cystic teratoma was pathologically confirmed. During the half-year follow-up, no symptoms were reported. This case constitutes the first report of the smallest primary intracardiac teratoma in an adult with a bicuspid aortic valve.

Valvular heart disease in congenital heart disease: a narrative review

Patients with congenital heart disease (CHD) are one of the fastest growing populations in cardiology, and valvular pathology is at the center of many congenital lesions. Derangements in valvular embryology lead to several anomalies prone to dysfunction, each with hemodynamic effects that require appropriate surveillance and management. Surgical innovation has provided new treatments that have improved survival in this population, though has also contributed to esotericism in patients who already have unique anatomic and physiologic considerations. Conduit and prosthesis durability are often monitored collaboratively with general and specialized congenital-focused cardiologists. As such, general cardiologists must become familiar with valvular disease with CHD for appropriate care and referral practices. In this review, we summarize the embryology of the semilunar and atrioventricular (AV) valves as a foundation for understanding the origins of valvular CHD and describe the mechanisms that account for heterogeneity in disease. We then highlight the categories of pathology from the simple (e.g., bicuspid aortic valve, isolated pulmonic stenosis) to the more complex (e.g., Ebstein's anomaly, AV valvular disease in single ventricle circulations) with details on natural history, diagnosis, and contemporary therapeutic approaches. Care for CHD patients requires collaborative effort between providers, both CHD-specialized and not, to achieve optimal patient outcomes.

Focused Strategies for Defining the Genetic Architecture of Congenital Heart Defects

Congenital heart defects (CHD) are malformations present at birth that occur during heart development. Increasing evidence supports a genetic origin of CHD, but in the process important challenges have been identified. This review begins with information about CHD and the importance of detailed phenotyping of study subjects. To facilitate appropriate genetic study design, we review DNA structure, genetic variation in the human genome and tools to identify the genetic variation of interest. Analytic approaches powered for both common and rare variants are assessed. While the ideal outcome of genetic studies is to identify variants that have a causal role, a more realistic goal for genetic analytics is to identify variants in specific genes that influence the occurrence of a phenotype and which provide keys to open biologic doors that inform how the genetic variants modulate heart development. It has never been truer that good genetic studies start with good planning. Continued progress in unraveling the genetic underpinnings of CHD will require multidisciplinary collaboration between geneticists, quantitative scientists, clinicians, and developmental biologists.

Update in Biomolecular and Genetic Bases of Bicuspid Aortopathy

Bicuspid aortic valve (BAV) associated with aortopathy is the most common congenital heart disease in the general population. Far from being a simple harmless valve malformation, it can be a complex and heterogeneous disease and a source of chronic and acute pathology (early valvular disease, aneurysm, dissection). In the previous years, intense research has been carried out to find out and understand its mechanisms, but the pathophysiology of the disease is still not fully understood and many questions remain open. Recent studies have discovered several genetic mutations involved in the development of valvular and aortic malformations, but still cannot explain more than 5–10% of cases. Other studies have also focused on molecular alterations and cellular processes (TGF-β pathway, microRNAs, degradation of the extracellular matrix, metalloproteinases, etc.), being a field in constant search and development, looking for a therapeutic target to prevent the development of the disease. Increased knowledge about this multifaceted disorder, derived from both basic and clinical research, may influence the diagnosis, follow-up, prognosis, and therapies of affected patients in the near future. This review focuses on the latest and outstanding developments on the molecular and genetic investigations of the bicuspid aortopathy.

Molecular and Mechanical Mechanisms of Calcification Pathology Induced by Bicuspid Aortic Valve Abnormalities

Bicuspid aortic valve (BAV) is a congenital defect affecting 1-2% of the general population that is distinguished from the normal tricuspid aortic valve (TAV) by the existence of two, rather than three, functional leaflets (or cusps). BAV presents in different morphologic phenotypes based on the configuration of cusp fusion. The most common phenotypes are Type 1 (containing one raphe), where fusion between right coronary and left coronary cusps (BAV R/L) is the most common configuration followed by fusion between right coronary and non-coronary cusps (BAV R/NC). While anatomically different, BAV R/L and BAV R/NC configurations are both associated with abnormal hemodynamic and biomechanical environments. The natural history of BAV has shown that it is not necessarily the primary structural malformation that enforces the need for treatment in young adults, but the secondary onset of premature calcification in ~50% of BAV patients, that can lead to aortic stenosis. While an underlying genetic basis is a major pathogenic contributor of the structural malformation, recent studies have implemented computational models, cardiac imaging studies, and bench-top methods to reveal BAV-associated hemodynamic and biomechanical alterations that likely contribute to secondary complications. Contributions to the field, however, lack support for a direct link between the external valvular environment and calcific aortic valve disease in the setting of BAV R/L and R/NC BAV. Here we review the literature of BAV hemodynamics and biomechanics and discuss its previously proposed contribution to calcification. We also offer means to improve upon previous studies in order to further characterize BAV and its secondary complications.

Multi-Omics Approaches to Define Calcific Aortic Valve Disease Pathogenesis

Calcific aortic valve disease sits at the confluence of multiple world-wide epidemics of aging, obesity, diabetes, and renal dysfunction, and its prevalence is expected to nearly triple over the next 3 decades. This is of particularly dire clinical relevance, as calcific aortic valve disease can progress rapidly to aortic stenosis, heart failure, and eventually premature death. Unlike in atherosclerosis, and despite the heavy clinical toll, to date, no pharmacotherapy has proven effective to halt calcific aortic valve disease progression, with invasive and costly aortic valve replacement representing the only treatment option currently available. This substantial gap in care is largely because of our still-limited understanding of both normal aortic valve biology and the key regulatory mechanisms that drive disease initiation and progression. Drug discovery is further hampered by the inherent intricacy of the valvular microenvironment: a unique anatomic structure, a complex mixture of dynamic biomechanical forces, and diverse and multipotent cell populations collectively contributing to this currently intractable problem. One promising and rapidly evolving tactic is the application of multiomics approaches to fully define disease pathogenesis. Herein, we summarize the application of (epi)genomics, transcriptomics, proteomics, and metabolomics to the study of valvular heart disease. We also discuss recent forays toward the omics-based characterization of valvular (patho)biology at single-cell resolution; these efforts promise to shed new light on cellular heterogeneity in healthy and diseased valvular tissues and represent the potential to efficaciously target and treat key cell subpopulations. Last, we discuss systems biology- and network medicine-based strategies to extract meaning, mechanisms, and prioritized drug targets from multiomics datasets.

Genetic and Developmental Contributors to Aortic Stenosis

Aortic stenosis (AS) remains one of the most common forms of valve disease, with significant impact on patient survival. The disease is characterized by left ventricular outflow obstruction and encompasses a series of stenotic lesions starting from the left ventricular outflow tract to the descending aorta. Obstructions may be subvalvar, valvar, or supravalvar and can be present at birth (congenital) or acquired later in life. Bicuspid aortic valve, whereby the aortic valve forms with two instead of three cusps, is the most common cause of AS in younger patients due to primary anatomic narrowing of the valve. In addition, the secondary onset of premature calcification, likely induced by altered hemodynamics, further obstructs left ventricular outflow in bicuspid aortic valve patients. In adults, degenerative AS involves progressive calcification of an anatomically normal, tricuspid aortic valve and is attributed to lifelong exposure to multifactoral risk factors and physiological wear-and-tear that negatively impacts valve structure-function relationships. AS continues to be the most frequent valvular disease that requires intervention, and aortic valve replacement is the standard treatment for patients with severe or symptomatic AS. While the positive impacts of surgical interventions are well documented, the financial burden, the potential need for repeated procedures, and operative risks are substantial. In addition, the clinical management of asymptomatic patients remains controversial. Therefore, there is a critical need to develop alternative approaches to prevent the progression of left ventricular outflow obstruction, especially in valvar lesions. This review summarizes our current understandings of AS cause; beginning with developmental origins of congenital valve disease, and leading into the multifactorial nature of AS in the adult population.

Effect of Losartan or Atenolol on Children and Young Adults With Bicuspid Aortic Valve and Dilated Aorta

Bicuspid aortic valve aortopathy is defined by dilation of the aortic root (AoRt) and/or ascending aorta (AsAo), and increases risk for aortic aneurysm and dissection. The effects of medical prophylaxis on aortic growth rates in moderate to severe bicuspid aortopathy have not yet been evaluated. This was a single-center retrospective study of young patients (1 day to 29 years) with bicuspid aortopathy (AoRt or AsAo z-score ≥ 4 SD, or absolute dimension ≥ 4 cm), treated with either losartan or atenolol. Maximal diameters and BSA-adjusted z-scores obtained from serial echocardiograms were utilized in a mixed linear effects regression model. The primary outcome was the annual rate of change in AoRt and AsAo z-scores during treatment, compared with before treatment. The mean ages (years) at treatment initiation were 14.2 ± 5.1 (losartan; n = 27) and 15.2 ± 4.9 (atenolol; n = 18). Median treatment duration (years) was 3.1 (IQR 2.4, 6.0) for losartan, and 3.7 (IQR 1.4, 6.6) for atenolol. Treatment was associated with decreases in AoRt and AsAo z-scores (SD/year), for both losartan and atenolol (pre- vs post-treatment): losartan/AoRt: +0.06 ± 0.02 vs -0.14 ± 0.03, p < 0.001; losartan/AsAo: +0.20 ± 0.03 vs -0.09 ± 0.05, p < 0.001; atenolol/AoRt: +0.07 ± 0.03 vs -0.02 ± 0.04, p = 0.04; atenolol/AsAo: +0.21 ± 0.04 vs -0.06 ± 0.06, p < 0.001. Treatment was also associated with decreases in absolute growth rates (cm/year) for all comparisons (p ≤ 0.02). Medical prophylaxis reduced proximal aortic growth rates in young patients with at least moderate and progressive bicuspid aortopathy.

Therapeutic approach comparison in bicuspid aortic valve aortopathy and clinical practice implications

Bicuspid aortic valve (BAV) is the most common heart valve malformation, and it may be associated with the development of long-term complications, such as aortic stenosis (AS) secondary to valvular calcification and aortic insufficiency (AI), with or without ascending aortic aneurysm (AAA). This study was performed at the Institute of Cardiovascular Diseases, Timişoara, Romania, from 2015 through 2018 and included a total of 105 patients with BAV. Out of the 105 BAV patients, 14 displayed AAA, alongside either AS or AI, and were selected undergo aortic valve replacement (AVR) alongside surgical replacement or aortoplasty of the ascending aorta, and the elastic fiber loss in the ascending aortic wall was evaluated for each patient. Two surgical interventions used alongside AVR in BAV patients with AAA and AS or AI were compared in this study: reduction ascending aortoplasty (RAA) and ascending aorta replacement (AAR). Postoperative follow-ups have shown RAA is useful short-term but that, in contrast to AAR, it leads to aortic redilatation over time. These results can contribute to a major future meta-analysis with the goal of improving the current clinical practice guidelines for BAV aortopathy.

Innovative approach to identify multigenomic and environmental interactions associated with birth defects in family-based hybrid designs

Genes, including those with transgenerational effects, work in concert with behavioral, environmental, and social factors via complex biological networks to determine human health. Understanding complex relationships between causal factors underlying human health is an essential step towards deciphering biological mechanisms. We propose a new analytical framework to investigate the interactions between maternal and offspring genetic variants or their surrogate single nucleotide polymorphisms (SNPs) and environmental factors using family-based hybrid study design. The proposed approach can analyze diverse genetic and environmental factors and accommodate samples from a variety of family units, including case/control-parental triads, and case/control-parental dyads, while minimizing potential bias introduced by population admixture. Comprehensive simulations demonstrated that our innovative approach outperformed the log-linear approach, the best available method for case-control family data. The proposed approach had greater statistical power and was capable to unbiasedly estimate the maternal and child genetic effects and the effects of environmental factors, while controlling the Type I error rate against population stratification. Using our newly developed approach, we analyzed the associations between maternal and fetal SNPs and obstructive and conotruncal heart defects, with adjustment for demographic and lifestyle factors and dietary supplements. Fourteen and 11 fetal SNPs were associated with obstructive and conotruncal heart defects, respectively. Twenty-seven and 17 maternal SNPs were associated with obstructive and conotruncal heart defects, respectively. In addition, maternal body mass index was a significant risk factor for obstructive defects. The proposed approach is a powerful tool for interrogating the etiological mechanism underlying complex traits.

Heart Disease and Stroke Statistics-2021 Update: A Report From the American Heart Association

BACKGROUND

The American Heart Association, in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2021 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population, an enhanced focus on social determinants of health, adverse pregnancy outcomes, vascular contributions to brain health, the global burden of cardiovascular disease, and further evidence-based approaches to changing behaviors related to cardiovascular disease.

RESULTS

Each of the 27 chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policy makers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Sex and Race Differences in the Pathophysiology, Diagnosis, Treatment, and Outcomes of Valvular Heart Diseases

Valvular heart diseases have long been considered to be similar in men and women and across races/ethnicities. Recently, studies have demonstrated major differences between sexes. Unfortunately, studies on valvular heart diseases, as on other cardiovascular diseases, are mostly performed in Caucasian men or in cohorts with a vast majority of Caucasian men. Therefore, our knowledge on valvular diseases in women and non-Caucasians remains limited. Nevertheless, aortic stenosis has been shown to be almost as prevalent in women as in men, and less prevalent in African Americans. Men appear to have a more calcified aortic valve lesion, and women tend to have a more fibrosed one. Primary mitral regurgitation is more frequent in women who have more rheumatic and Barlow etiologies, whereas men have more fibroelastic deficiency and posterior leaflet prolapse/flail. Left ventricular remodelling due to valvular heart diseases is sex related in terms of geometry and probably also in composition of the tissue. Outcomes seem to be worse in women after surgical interventions and better than or equivalent to men after transcatheter ones. Regarding other valvular heart diseases, very few studies are available: Aortic regurgitation is more frequent in men, isolated tricuspid regurgitation more frequent in women. Rheumatic valve diseases are more frequent in women and are mostly represented by mitral and aortic stenoses. Many other sex/gender- and race/ethnic-specific studies are still needed in epidemiology, pathophysiology, presentation, management, and outcomes. This review aims to report the available data on sex differences and race specificities in valvular heart diseases, with a primary focus on aortic stenosis and mitral regurgitation.

Quadricuspid aortic valve: a case report and review of literature

Quadricuspid aortic valve, a rare congenital cardiac defect, manifests most commonly as aortic regurgitation. Clinical presentation mainly depends on the functional status of the aortic valve, myocardium and associated cardiovascular abnormalities. Aortic valve replacement or repair is usually warranted in the 5th or 6th decade.

Genetic Etiology of Left-Sided Obstructive Heart Lesions: A Story in Development

Congenital heart disease is the most common congenital defect observed in newborns. Within the spectrum of congenital heart disease are left‐sided obstructive lesions (LSOLs), which include hypoplastic left heart syndrome, aortic stenosis, bicuspid aortic valve, coarctation of the aorta, and interrupted aortic arch. These defects can arise in isolation or as a component of a defined syndrome; however, nonsyndromic defects are often observed in multiple family members and associated with high sibling recurrence risk. This clear evidence for a heritable basis has driven a lengthy search for disease‐causing variants that has uncovered both rare and common variants in genes that, when perturbed in cardiac development, can result in LSOLs. Despite advancements in genetic sequencing platforms and broadening use of exome sequencing, the currently accepted LSOL‐associated genes explain only 10% to 20% of patients. Further, the combinatorial effects of common and rare variants as a cause of LSOLs are emerging. In this review, we highlight the genes and variants associated with the different LSOLs and discuss the strengths and weaknesses of the present genetic associations. Furthermore, we discuss the research avenues needed to bridge the gaps in our current understanding of the genetic basis of nonsyndromic congenital heart disease.

First-Degree Relatives Screening of Patients with Bicuspid Aortic Valve: Effectiveness and Feasibility in Pediatric Cardiology Daily Practice

Bicuspid aortic valve (BAV) is the most common congenital heart disease. Since heritability is suspected, actual guidelines recommend to perform an echocardiographic assessment for first-degree relatives (FDR) of patient with BAV. This study aimed to assess the effectiveness and the feasibility of the current guidelines for the screening of FDR of patient with BAV in a pediatric cardiology daily practice. Consecutive patients with BAV and their FDR were prospectively included from January 2015 to March 2018 at Centre Hospitalier Universitaire de Laval, Quebec City (Canada). Data were retrospectively collected and analyzed. A total of 713 FDR of 213 consecutives index cases [median age: 11 (6-20) years] were studied. Up to 32 (6.6%) FDR had a BAV and 26 (5.4%) had an aortic valve dysfunction. A total of 14 (2.9%) FDR had an ascending aorta dilatation according to Z-score including 6 (1.2%) patients with an ascending aorta ≥ 45 mm. No statistically significant differences regarding BAV, aortic valve dysfunction and ascending aorta dilatation prevalence were identified between generations. Screening was done in 482 (67.6%), prescribed but not done in 134 (19%), not prescribed in 92 (13%) and declined in 5 (1%) FDR. The prevalence of BAV in FDR was similar to prospective adult studies and supports actual guidelines in pediatric cardiology practice. Ascending aorta dilatation was rare in our young population. Exhaustiveness and additional burden to implement current guidelines remain a challenge in daily practice.

A de novo pathogenic BMP2 variant-related phenotype with the novel finding of bicuspid aortic valve

A rare autosomal dominant syndrome with craniofacial dysmorphisms, skeletal abnormalities, short stature, and congenital heart defects has recently been described, associated with monoallelic truncating and frameshift bone morphogenetic protein 2 (BMP2) variants and deletions. We describe a patient harboring a novel de novo BMP2 nonsense variant, who exhibited craniofacial and skeletal features previously described for this trait and the novel findings of bicuspid aortic valve (BAV) and aortic root and ascending aortic aneurysm. This first instance of aortic valve involvement provides another potential cause of BAV and confirms the role of BMP2 in left ventricular outflow development.

Prevalence rates study of selected isolated non-Mendelian congenital anomalies in the Hutterite population of Alberta, 1980-2016

A study of the prevalence rates for selected isolated non-Mendelian congenital anomalies in the Hutterite Brethren of Alberta, Canada was undertaken to further examine longitudinal data in this isolated community that was last reported in 1985 (Lowry et al., 1985), although there are numerous publications on recessive disorders (Boycott et al., 2008; Triggs-Raine et al., 2016). Cases were ascertained from the Alberta Congenital Anomaly Surveillance System for the years 1997-2016. Since our initial results showed some surprising findings in the Hutterite Brethren, such as zero cases of spina bifida, cleft lip and palate, gastroschisis, and omphalocele, and a significant excess of cases with hypospadias, we extended the study to prior years (1980-1996) for selected anomalies. For the extended study period (1980-2016), there was a significant increased prevalence of hypospadias, tetralogy of Fallot and tricuspid atresia in the Hutterite population, and although not statistically significant, zero cases of cleft lip with cleft palate, gastroschisis and omphalocele were confirmed. Further research is needed to determine the precise effects of rural environmental exposures, lifestyle factors, and genetic associations for selected multifactorial congenital anomalies.

Rare deleterious variants of NOTCH1, GATA4, SMAD6, and ROBO4 are enriched in BAV with early onset complications but not in BAV with heritable thoracic aortic disease

Background

Bicuspid aortic valve (BAV) is the most common cardiovascular malformation in adults, with a prevalence of 0.5%–2%. The prevalence of BAV in cohorts who were ascertained due to thoracic aortic aneurysms or acute aortic dissections (TAD) is as high as 20%. However, the contribution of causal BAV genes to TAD is not known. Therefore, we evaluated rare deleterious variants of GATA4, NOTCH1, SMAD6, or ROBO4 in patients with BAV who presented with TAD.

Methods

Our cohort consisted of 487 probands with Heritable Thoracic Aortic Aneurysms or Dissections (HTAD, 12% BAV, 29% female) and 63 probands with Early onset complications of Bicuspid Aortic Valve disease (EBAV, 63% TAD, 34% female). After whole exome sequencing, we functionally annotated GATA4, NOTCH1, SMAD6, and ROBO4 variants and compared the prevalence of rare variants in these genes to controls without HTAD.

Results

We identified 11 rare deleterious variants of GATA4, SMAD6, or ROBO4 in 12 (18%) EBAV cases. The burden of rare SMAD6 and GATA4 variants was significantly enriched in EBAV but not in HTAD cases, even among HTAD cases with BAV (p < .003).

Conclusion

Rare variants of NOTCH1, ROBO4, SMAD6, or GATA4 do not significantly contribute to BAV in cohorts with HTAD. We conclude that BAV patients who present with HTAD are a genetically distinct subgroup with implications for genetic testing and prognosis.

Mechanisms of heart valve development and disease

The valves of the heart are crucial for ensuring that blood flows in one direction from the heart, through the lungs and back to the rest of the body. Heart valve development is regulated by complex interactions between different cardiac cell types and is subject to blood flow-driven forces. Recent work has begun to elucidate the important roles of developmental pathways, valve cell heterogeneity and hemodynamics in determining the structure and function of developing valves. Furthermore, this work has revealed that many key genetic pathways involved in cardiac valve development are also implicated in diseased valves. Here, we review recent discoveries that have furthered our understanding of the molecular, cellular and mechanosensitive mechanisms of valve development, and highlight new insights into congenital and acquired valve disease.

Causes, Diagnosis, Risk Stratification and Treatment of Bicuspid Aortic Valve Disease: An Updated Review

The most common congenital heart disease is the bicuspid aortic valve. Understanding the pathophysiology and the altered hemodynamics is a key component for the diagnosis, risk stratification and treatment. Among others, aortic valve stenosis is the most common complication. Treatment strategies vary depending on the severity of the disease, particularly the dilation of the aorta playing a major role. Together with valve replacement, transcatheter aortic valve implantation is now considered as an alternative option with good results. With this review we would like to discuss the causes, diagnostic methods, risk stratification and treatment strategies of the bicuspid aortic valve.

Multimodality imaging in bicuspid aortic valve

Bicuspid aortic valve (BAV) patients are at increased risk of valve dysfunction and ascending aorta aneurysm. Imaging techniques are essential to establish diagnosis, identify complications and indicate surgical treatment. Transthoracic echocardiography (TTE) is the imaging technique of choice to diagnose BAV, valve morphotype and valvular dysfunction in clinical practice. However, it can be less precise in assessing the aortic root and proximal ascending aorta, and visualization of the mid-distal ascending aorta and the arch may be difficult in some adults where cardiac magnetic resonance (CMR) and computed tomography, using multiplanar reconstructions, are better at assessing aortic diameters. Although valvular dysfunction is very variable, almost half of the patients have more than mild aortic valve disease. TTE is the most effective and accurate test for evaluating the severity of valvular dysfunction and guiding appropriate management decisions. Aorta dilation is a common finding in patients with BAV. The pattern of aortic dimensions has been categorized in three aortic phenotypes: no-dilation phenotype, ascending aorta phenotype and root phenotype. Controversial data exist regarding the relationship between BAV morphology and aorta dilation phenotype. The assessment of aortic stiffness (measuring distensibility or the velocity of propagation of flow) has raised special interest in order to predict progressive aorta dilation. However, current data indicates that BAV aortas do not show altered stiffness compared to those associated with a tricuspid valve with a similar aorta size. Moreover, novel 4D-flow CMR sequences have been crucial in the evaluation of abnormal ascending aorta flow, showing that flow in the aorta of BAV patients is asymmetric and includes the formation of large vortices. Such flow abnormalities are thought to produce changes in wall shear stress which has been associated with extracellular matrix dysregulation. The key points to understand familial screening and the recommendations for establishing the follow-up and therapeutic management of BAV patients are exposed in the review. The main objective of this article is to review the advantages and limitations of the imaging techniques in the diagnosis and management of BAV and the best strategies in the use of multimodality imaging.

Genetics in bicuspid aortic valve disease: Where are we?

Bicuspid aortic valve (BAV) is the most common congenital heart defect, found in up to 2% of the population and associated with a 30% lifetime risk of complications. BAV is inherited as an autosomal dominant trait with incomplete penetrance and variable expressivity due to a complex genetic architecture that involves many interacting genes. In this review, we highlight the current state of knowledge about BAV genetics, principles and methods for BAV gene discovery, clinical applications of BAV genetics, and important future directions.

Clinical history and management of bicuspid aortic valve in children and adolescents

Bicuspid aortic valve (BAV) is one of the most common congenital heart defects in children, adolescents and adults. BAV can occur as an isolated lesion or in association with other congenital heart defects, such as coarctation of the aorta or genetic syndromes like Turner syndrome. Although the majority of long term complications associated with BAV manifest later in life, children and adolescents may present with early onset valvular dysfunction or dilation of the aorta. BAV is a heterogeneous disease with a wide array of presentations at various ages, depending on the degree of aortic valve dysfunction, aortic dilation and presence of associated lesions. Aortic valve stenosis and/or regurgitation are the primary indications for intervention in children and adolescents with BAV. Although a majority of young patients with BAV also have some aortic dilation, interventions on the aorta are very rare during this time frame. Children and adolescents with BAV benefit from comprehensive assessment of their risk profile to determine follow-up surveillance intervals, sports recommendations, and timing of surgical intervention. The morphologic phenotype of BAV is important to identify, as it may predict future complications and prognosis.

The impact of the aortic cusps fusion pattern and valve disease severity on the aortic wall mechanics in patients with bicuspid aortic valve

The ascending aorta dilatation in the bicuspid aortic valve (BAV) patients is often attributed to congenital abnormalities of the aortic wall, but it may be related to hemodynamic disturbances in the course of BAV disease. At present, ascending aortic diameter is used as almost sole but weak predictor of aortic dissection and rupture in BAV. We examined the association between aortic wall mechanics and severity of aortic valve disease including different cusps fusion patterns using conventional echocardiography and tissue Doppler imaging (TDI). We prospectively studied 106 BAV patients: 72 with right-left (R-L) coronary cusp fusion were matched 1:1 to 34 patients with right-noncoronary (R-N) cusp fusion obtaining 34 pairs of patients. Peak systolic radial velocity and acceleration of the ascending aortic wall, measured by TDI, were used as an index of hemodynamic stress imposed on the aorta. Paired analysis showed higher aortic wall radial velocity (4.71 ± 1.61 cm/s vs. 3.33 ± 1.44 cm/s, p = 0.001) and acceleration (1.08 ± 0.46 m/s² vs. 0.80 ± 0.34 m/s², p = 0.015) in-R-L compared to R-N fusion. Pearson correlation showed association of ascending tubular aortic diameter with age (r = 0.258, p = 0.012), weight (r = 0.323, p = 0.001), peak aortic valve gradient (r = 0.386, p = 0.0001), aortic root diameter (r = 0.439, p < 0.0001), and R-N fusion pattern (r = 0.209, p = 0.043). Aortic root diameter was related to male gender (r = 0.296, p = 0.003), weight (r = 0.381, p = 0.0001), ascending aortic diameter (r = 0.439, p < 0.0001), and severity of aortic regurgitation (r = 0.337, p = 0.0009). Regional differences in aortic wall motion between different BAV cusp fusion patterns and association of aortic diameters with the severity of aortic valve disease, both suggest a deleterious hemodynamic impact of cusp fusion patterns and aortic valve dysfunction on ascending aortic wall. Assessment of aortic hemodynamic by TDI is feasible and could be potentially used to improve prediction of acute aortic complications, thus helping to establish optimal timing of aortic surgery in BAV patients.

Predictors of Bicuspid Aortic Valve–Associated Aortopathy in Childhood

Background:

Bicuspid aortic valve (BAV) is the most prevalent congenital heart defect affecting 1% to 2% of the population. It is associated with ascending aorta dilatation. Valve morphology, aortic stenosis (AS), and aortic insufficiency (AI) have been proposed as potential risk factors; however, evaluating their role is difficult, as these factors are inherently related. The aim of this study was to determine whether BAV morphology and dysfunction are independent determinants for ascending aorta dilatation in pediatric patients.

Methods:

A multicenter, retrospective, cross-sectional study of pediatric BAV patients followed since 2004 was performed. Imaging data were assessed for BAV morphology, severity of AS and AI, history of coarctation, and aortic dimensions. Associations were determined using multivariable regression analysis. A subset of patients undergoing aortic interventions (balloon dilation or Ross) were assessed longitudinally.

Results:

Data were obtained from 2122 patients (68% male; median age 10.2 years). Fifty percent of patients had ascending aorta dilatation. Right and noncoronary cusp fusion, increasing AS and AI, and older age were independently associated with ascending aorta dilatation. A history of coarctation was associated with less ascending aorta dilatation. In patients with neither AS nor AI, 37% had ascending aorta dilatation (4% severe). No complications related to aortic dilatation occurred in this cohort. Aortic Z scores were determined, and a Z -score calculator was created for this population.

Conclusions:

In this large pediatric cohort of patients with BAV, valve morphology, AS, and AI are independently associated with ascending aorta dilatation, suggesting that hemodynamic factors influence aortopathy. However, even in BAVs with no AS or AI, there is significant ascending aorta dilatation independent of valve morphology. Interventions that led to changes in degree of AI and AS did not seem to influence change in aortic dimensions. The current BAV cohort can be used as a reference group for expected changes in aortic dimensions during childhood.

The importance of genetics and genetic counselors in the evaluation of patients with bicuspid aortic valve and aortopathy

PURPOSE OF REVIEW

Bicuspid aortic valve (BAV) is a common congenital heart defect, with an estimated frequency of 1-2% in the general population. BAV may occur as an isolated finding or as a feature of certain syndromes. This article discusses potential genetic causes of BAV, includes a list of current known and candidate genes associated with BAV, provides a hypothetical case demonstrating the importance of genetic testing and cascade screening, and highlights the value of genetic counselors specializing in cardiovascular genetics.

RECENT FINDINGS

Individuals with BAV are at significantly increased risk of progressive aortic valve disease and aortic root aneurysms. There is high heritability associated with BAV, and several specific genes have recently been associated with BAV. There is wide phenotypic variability among BAV malformations, including which cusps are involved and the degree of aortic root involvement. Genotype-phenotype correlations exist that impact treatment recommendations. Genetic testing can reduce morbidity and mortality by guiding management strategies and identifying asymptomatic relatives before significant complications occur.

SUMMARY

Identifying cases of BAV with an identifiable genetic cause can significantly impact patients and family members. The list of associated genes is constantly growing. Genetic counselors have an important role in the evaluation of families at risk of BAV.