Bicuspid Aortic Valve Morphology and Interventions in the Young

Bicuspid aortic valve: The most frequent and not so benign congenital heart disease

Bicuspid aortic valve (BAV) is the most frequent congenital heart disease, with an incidence of approximately 1%. It can be silent and associated with normal valve function. However, a series of complications, even catastrophic, may occur with time: valve incompetence, valve stenosis by dystrophic calcification, infective endocarditis, progressive dilatation of the ascending aorta, aortic dissection, sudden death. The problem of BAV is not just about the number of semilunar cusps, but also the aortic wall. Severe noninflammatory degenerative changes (elastic fiber fragmentation, smooth muscle cells death, mucoid extracellular matrix accumulation=MEMA) are observed in the aortic wall of BAV patients, with intrinsic weakness accounting for progressive aneurysmal dilatation of the ascending aorta, valve incompetence, and wall dissection. The link between valve and aortic wall pathology finds most probably an explanation in the embryology of the arterial pole since neurocrestal cells play a role in the development of both the ascending aorta, aortic arch, and semilunar valves. The frequent association of adult aortic coarctation and BAV provides evidence for this hypothesis. BAV has a significant genetic component as to require screening of first-degree relatives, as outlined by AHA/ACC 2022 guidelines.

Effect of patient factors, center, and era on Fontan timing: An observational study using the Pediatric Health Information Systems Database

BACKGROUND

There are no consensus guidelines defining optimal timing for the Fontan operation, the last planned surgery in staged palliation for single-ventricle heart disease.

OBJECTIVES

Identify patient-level characteristics, center-level variation, and secular trends driving Fontan timing.

METHODS

A retrospective observational study of subjects who underwent Fontan from 2007 to 2021 at centers in the Pediatric Health Information Systems database was performed using linear mixed-effects modeling in which age at Fontan was regressed on patient characteristics and date of operation with center as random effect.

RESULTS

We included 10,305 subjects (40.4% female, 44% non-white) at 47 centers. Median age at Fontan was 3.4 years (IQR 2.6-4.4). Hypoplastic left heart syndrome (-4.4 months, 95%CI -5.5 to -3.3) and concomitant conditions (-2.6 months, 95%CI -4.1 to -1.1) were associated with younger age at Fontan. Subjects with technology-dependence (+4.6 months, 95%CI 3.1-6.1) were older at Fontan. Black (+4.1 months, 95%CI 2.5-5.7) and Asian (+8.3 months, 95%CI 5.4-11.2) race were associated with older age at Fontan. There was significant variation in Fontan timing between centers. Center accounted for 10% of variation (ICC 0.10, 95%CI 0.07-0.14). Center surgical volume was not associated with Fontan timing (P = .21). Operation year was associated with age at Fontan, with a 3.1 month increase in age for every 5 years (+0.61 months, 95%CI 0.48-0.75).

CONCLUSIONS

After adjusting for patient-level characteristics there remains significant inter-center variation in Fontan timing. Age at Fontan has increased. Future studies addressing optimal Fontan timing are warranted.

Characteristics and outcomes of the Spanish registry for pediatric patients with bicuspid aortic valve (REVAB)

INTRODUCTION AND OBJECTIVES

Bicuspid aortic valve (BAV) disorder is the most common congenital heart disease. The aim of this study was to describe the characteristics of 0- to 18-year olds with BAV in a population-based registry.

METHODS

Data from all pediatric patients were obtained from the Spanish registry for pediatric patients with bicuspid aortic valve (REVAB) (< 18 years). For data analysis, patients with BAV were divided into 2 groups by their features: isolated BAV and BAV with associated congenital heart disease.

RESULTS

We included 1681 patients from 33 hospitals. Males accounted for 69.6% (n = 1158). Valve morphology was horizontal in 63.4% (n = 1012) and pure (Sievers type 0) in 28.4% (n=469). Isolated BAV was present in 63.7% (n=1060), and concomitant left-sided obstructive lesions in 23.4% (n=390). Interventions were required in 8.6% (n=145).

CONCLUSION

These data represent the first large, population-based description of the clinical presentations and outcomes of patients enrolled in the Spanish registry for pediatric patients with bicuspid aortic valve.

Bicuspid aortic valve: evolving knowledge and new questions

Bicuspid aortic valve (BAV), a common congenital anomaly with various morphological phenotypes, is also characterised by marked heterogeneity in clinical presentations including clinically silent condition with mild valvulo-aortopathy, progressive valvulopathy and complex valvulo-aortopathy with shorter life expectancy. The clinical importance of using a general and unified nosology for BAV is well-accepted by opinion leaders and an international consensus statement has been recently published, which will serve as an important scientific platform for BAV. This review describes the current knowledge of BAV based on clinical studies, addresses several unresolved issues requiring investigators' attention and highlights the necessity of prospective studies with a very long follow-up duration for better appreciation of BAV-associated valvulo-aortopathy. In addition, the progression of valvular calcification in patients with BAV and its potential contribution to development of valvulopathy will be discussed.

"Y" incision and rectangular patch enlargement of aortic annulus and valve reconstruction with autologous pericardium in congenital aortic stenosis

Surgical aortic valve replacement in children who have undergone prior balloon or surgical valvuloplasty or both is a formidable challenge. The aortic annulus is small, there is no ideal prosthesis and lifelong anticoagulation is highly undesirable. A "Y" incision and rectangular patch enlargement of the aortic annulus introduced by Dr. Bo Yang in 2020 combined with aortic valve reconstruction introduced by Dr. Shigeyuki Ozaki in 2011, is feasible, as described in this case.

Perspectives on pediatric congenital aortic valve stenosis: Extracellular matrix proteins, post translational modifications, and proteomic strategies

In heart valve biology, organization of the extracellular matrix structure is directly correlated to valve function. This is especially true in cases of pediatric congenital aortic valve stenosis (pCAVS), in which extracellular matrix (ECM) dysregulation is a hallmark of the disease, eventually leading to left ventricular hypertrophy and heart failure. Therapeutic strategies are limited, especially in pediatric cases in which mechanical and tissue engineered valve replacements may not be a suitable option. By identifying mechanisms of translational and post-translational dysregulation of ECM in CAVS, potential drug targets can be identified, and better bioengineered solutions can be developed. In this review, we summarize current knowledge regarding ECM proteins and their post translational modifications (PTMs) during aortic valve development and disease and contributing factors to ECM dysregulation in CAVS. Additionally, we aim to draw parallels between other fibrotic disease and contributions to ECM post-translational modifications. Finally, we explore the current treatment options in pediatrics and identify how the field of proteomics has advanced in recent years, highlighting novel characterization methods of ECM and PTMs that may be used to identify potential therapeutic strategies relevant to pCAVS.

Patients with Bicuspid Aortopathy and Aortic Dilatation

(1) Background: Bicuspid aortic valve (BAV) is the most frequent congenital cardiac disease. Alteration of ascending aorta diameter is a consequence of shear stress alterations due to haemodynamic abnormalities developed from inadequate valve cusp coaptation. (2) Objective: This narrative review aims to discuss anatomical, pathophysiological, genetical, ultrasound, and radiological aspects of BAV disease, focusing on BAV classification related to imaging patterns and flux models involved in the onset and developing vessel dilatation. (3) Methods: A comprehensive search strategy was implemented in PubMed from January to May 2022. English language articles were selected independently by two authors and screened according to the following criteria. (4) Key Contents and Findings: Ultrasound scan is the primary step in the diagnostic flowchart identifying structural and doppler patterns of the valve. Computed tomography determines aortic vessel dimensions according to the anatomo-pathology of the valve. Magnetic resonance identifies hemodynamic alterations. New classifications and surgical indications derive from these diagnostic features. Currently, indications correlate morphological results, dissection risk factors, and genetic alterations. Surgical options vary from aortic valve and aortic vessel substitution to aortic valve repair according to the morphology of the valve. In selected patients, transcatheter aortic valve replacement has an even more impact on the treatment choice. (5) Conclusions: Different imaging approaches are an essential part of BAV diagnosis. Morphological classifications influence the surgical outcome.

Outcome and Impact of Associated Left-Sided Cardiac Lesions in Coarctation of the Aorta Diagnosed During Fetal Life

Significant effort has been put into the optimization of the antenatal diagnosis of coarctation of the aorta (CoA). However, although left-sided cardiac lesions are known to cluster, the necessity to intervene postnatally for other left-sided cardiac lesions has not been reported in a cohort of fetuses with suspected CoA. We report a study of all 89 fetuses with antenatally suspected and postnatally confirmed diagnosis of CoA who underwent CoA repair as the primary procedure at a single tertiary congenital heart disease center over 10 years (January 1, 2010, to December 31, 2019). Almost 1 in 5 patients (18%) had to undergo surgery and/or transcatheter intervention on additional left-sided cardiac lesions (14%) and/or reintervention on the aortic arch (12%) during follow-up to median age of 2.85 years. Freedom from intervention at 5 years was 78% (95% confidence interval [CI] 67 to 88%) if reintervention on CoA was excluded, and 72% (95% CI 60 to 82%) if this was included. Five-year survival was 95% (95% CI 90 to 100%). Furthermore, 20% of affected infants had genetic (10%) and/or extracardiac (16%) abnormalities. Our study highlights the need for comprehensive antenatal counseling, including the prognosis of primary repair of CoA and the potential development of additional left-sided cardiac lesions, which may be difficult to diagnose prenatally even in expert hands or impossible to diagnose because of the physiology of the fetal circulation.

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 between bicuspid aortic valve phenotype and patterns of valvular dysfunction: A meta-analysis

Background

Valvular dysfunction is a common complication in patients with bicuspid aortic valves (BAV). The aim of this study was to determine the relationship between BAV morphology patterns and valve dysfunction.

Methods

We searched the PubMed, The Cochrane Library, Web of Science, and CNKI until May 31, 2020, to identify all studies investigating the morphology of BAV and valvular dysfunction, and data were extracted according to the Preferred Reporting Items for Systematic reviews and Meta‐Analyses (PRISMA). Data were analyzed using Stata 15.1 software. The additional characteristics (gender, mean age) were collected to perform a meta‐regression analysis.

Results

Thirteen studies on BAV‐RL (n = 2002) versus BAV‐RN (n = 1254) and raphe (n = 4001) versus without raphe (n = 673) were included. The BAV‐RL patients showed a higher incidence of aortic regurgitation than BAV‐RN patients (OR = 1.46; 95% CI: 1.12 to 1.90, p = .005), while the BAV‐RL patients showed a lower incidence of aortic stenosis than BAV‐RN patients (OR = 0.66, 95% CI: 0.58 to 0.76, p = .000); BAV patients with raphe presents a higher incidence of aortic regurgitation than those without raphe (OR = 1.95, 95% CI: 1.12–3.39, p = .017). No differences were found between raphe and without raphe group in the incidence of aortic stenosis (OR = 0.97, 95% CI: 0.53 to 1.76, p = .907). Mean age and gender had no influence on observed differences.

Conclusions

Our results confirmed a relationship between different BAV phenotypes and aortic valve dysfunction. BAV‐RL and BAV with raphe are more likely to develop aortic regurgitation, while patients with BAV‐RN present a higher possibility to develop aortic stenosis.

Treatment of Bicuspid Aortic Valve Stenosis Using Transcatheter Heart Valves

The paucity of data regarding the use of transcatheter aortic valve replacement (TAVR) in bicuspid aortic valve (BAV) anatomy due to exclusion from pivotal studies and lack of studies assessing the long-term outcomes and valve performance continue to present a significant challenge as we expand TAVR to patients with BAV anatomy. This article discusses the important anatomic and clinical considerations in the selection and management of patients with BAV with TAVR and reviews the emerging evidence that increasingly suggests this procedure is safe, device success is excellent, and procedural outcomes are improving.

International Consensus Statement on Nomenclature and Classification of the Congenital Bicuspid Aortic Valve and Its Aortopathy, for Clinical, Surgical, Interventional and Research Purposes

This International Consensus Classification and Nomenclature for the congenital bicuspid aortic valve condition recognizes 3 types of bicuspid valves: 1. The fused type (right-left cusp fusion, right-non-coronary cusp fusion and left-non-coronary cusp fusion phenotypes); 2. The 2-sinus type (latero-lateral and antero-posterior phenotypes); and 3. The partial-fusion (forme fruste) type. The presence of raphe and the symmetry of the fused type phenotypes are critical aspects to describe. The International Consensus also recognizes 3 types of bicuspid valve-associated aortopathy: 1. The ascending phenotype; 2. The root phenotype; and 3. Extended phenotypes. ©  2021 Jointly between the RSNA, the European Association for Cardio-Thoracic Surgery, The Society of Thoracic Surgeons, and the American Association for Thoracic Surgery. The articles are identical except for minor stylistic and spelling differences in keeping with each journal's style. All rights reserved. Keywords: Bicuspid Aortic Valve, Aortopathy, Nomenclature, Classification.

Summary: international consensus statement on nomenclature and classification of the congenital bicuspid aortic valve and its aortopathy, for clinical, surgical, interventional and research purposes

This International evidence-based nomenclature and classification consensus on the congenital bicuspid aortic valve and its aortopathy recognizes 3 types of bicuspid aortic valve: 1. Fused type, with 3 phenotypes: right-left cusp fusion, right-non cusp fusion and left-non cusp fusion; 2. 2-sinus type with 2 phenotypes: Latero-lateral and antero-posterior; and 3. Partial-fusion or forme fruste. This consensus recognizes 3 bicuspid-aortopathy types: 1. Ascending phenotype; root phenotype; and 3. extended phenotypes.

International consensus statement on nomenclature and classification of the congenital bicuspid aortic valve and its aortopathy, for clinical, surgical, interventional and research purposes

This International Consensus Classification and Nomenclature for the congenital bicuspid aortic valve condition recognizes 3 types of bicuspid valves: 1. The fused type (right-left cusp fusion, right-non-coronary cusp fusion and left-non-coronary cusp fusion phenotypes); 2. The 2-sinus type (latero-lateral and antero-posterior phenotypes); and 3. The partial-fusion (forme fruste) type. The presence of raphe and the symmetry of the fused type phenotypes are critical aspects to describe. The International Consensus also recognizes 3 types of bicuspid valve-associated aortopathy: 1. The ascending phenotype; 2. The root phenotype; and 3. Extended phenotypes.

Summary: International consensus statement on nomenclature and classification of the congenital bicuspid aortic valve and its aortopathy, for clinical, surgical, interventional, and research purposes

This International evidence-based nomenclature and classification consensus on the congenital bicuspid aortic valve and its aortopathy recognizes 3 types of bicuspid aortic valve: 1. Fused type, with 3 phenotypes: right-left cusp fusion, right-non cusp fusion and left-non cusp fusion; 2. 2-sinus type with 2 phenotypes: Latero-lateral and antero-posterior; and 3. Partial-fusion or forme fruste. This consensus recognizes 3 bicuspid-aortopathy types: 1. Ascending phenotype; root phenotype; and 3. extended phenotypes.

International consensus statement on nomenclature and classification of the congenital bicuspid aortic valve and its aortopathy, for clinical, surgical, interventional and research purposes

This International Consensus Classification and Nomenclature for the congenital bicuspid aortic valve condition recognizes 3 types of bicuspid valves: 1. The fused type (right-left cusp fusion, right-non-coronary cusp fusion and left-non-coronary cusp fusion phenotypes); 2. The 2-sinus type (latero-lateral and antero-posterior phenotypes); and 3. The partial-fusion (forme fruste) type. The presence of raphe and the symmetry of the fused type phenotypes are critical aspects to describe. The International Consensus also recognizes 3 types of bicuspid valve-associated aortopathy: 1. The ascending phenotype; 2. The root phenotype; and 3. Extended phenotypes.

Summary: International Consensus Statement on Nomenclature and Classification of the Congenital Bicuspid Aortic Valve and Its Aortopathy, for Clinical, Surgical, Interventional and Research Purposes

This International evidence-based nomenclature and classification consensus on the congenital bicuspid aortic valve and its aortopathy recognizes 3 types of bicuspid aortic valve: 1. Fused type, with 3 phenotypes: right-left cusp fusion, right-non cusp fusion and left-non cusp fusion; 2. 2-sinus type with 2 phenotypes: Latero-lateral and antero-posterior; and 3. Partial-fusion or forme fruste. This consensus recognizes 3 bicuspid-aortopathy types: 1. Ascending phenotype; root phenotype; and 3. extended phenotypes.

International Consensus Statement on Nomenclature and Classification of the Congenital Bicuspid Aortic Valve and Its Aortopathy, for Clinical, Surgical, Interventional and Research Purposes

This International Consensus Classification and Nomenclature for the congenital bicuspid aortic valve condition recognizes 3 types of bicuspid valves: 1. The fused type (right-left cusp fusion, right-non-coronary cusp fusion and left-non-coronary cusp fusion phenotypes); 2. The 2-sinus type (latero-lateral and antero-posterior phenotypes); and 3. The partial-fusion (forme fruste) type. The presence of raphe and the symmetry of the fused type phenotypes are critical aspects to describe. The International Consensus also recognizes 3 types of bicuspid valve-associated aortopathy: 1. The ascending phenotype; 2. The root phenotype; and 3. Extended phenotypes.

Sex Differences in Children and Young Adults With Bicuspid Aortic Valve Disease in First Two Decades of Life

OBJECTIVE

To elucidate sex differences in valve morphology, disease phenotype, progression, and outcomes among children and young adults with bicuspid aortic valve (BAV).

PATIENTS AND METHODS

This is a retrospective cohort study examining all children and young adults (aged ≤22 years) with isolated BAV diagnosed, by excluding patients with concomitant congenital heart defects or genetic syndromes, from January 1, 1990, through December 1, 2016, at Mayo Clinic in Rochester, Minnesota.

RESULTS

Of 1010 patients with BAV, 558 had isolated BAV. Distributions of morphology were right-left in 65.8% (n=367), right-noncoronary in 34% (n=190), and left-noncoronary cusp fusion in 0.2% (n=1) of patients; with no sex differences. Male to female ratio was 3:1. At the first echocardiographic evaluation in the study, there were no sex differences in terms of frequency of aortic valve stenosis or regurgitation. However, males had significantly higher grades of aortic valve regurgitation at 17 years of age onward (P<.0001). Males had significantly larger mid-ascending aorta (P=.01) and sinus of Valsalva dimensions (z score; P=.0001) as compared with females, with a novel finding of peak aortic dimensions around 8 years of age. Males also had more than 2-fold higher risk for sinus of Valsalva dilation (z score >2) as compared with females (odds ratio, 2.3; 95% CI, 1.2 to 4.2; P=.01). There were no significant sex differences in the primary cardiac outcomes of interventions on aortic valve and/or aorta, aortic dissection, or death.

CONCLUSION

In children and young adults with BAV, males have a higher grade of aortic regurgitation in late adolescence, significantly larger aortic dimensions, different patterns of aortic growth, and more frequent sinus of Valsalva dilation as compared with females. Overall, the rate of primary cardiac events is lower in young patients, with no significant sex differences.

Pathology of the Aorta and Aorta as Homograft

The aorta is not a rigid tube, it is an “organ” with lamellar units, consisting of elastic fibers, extracellular matrix and smooth muscle cells in between as parenchyma. Several diseases may occur in the natural history of the aorta, requiring replacement of both semilunar cusps and ascending aorta. They may be congenital defects, such as bicuspid aortic valve and isthmal coarctation with aortopathy; genetically determined, such as Marfan and William syndromes; degenerative diseases, such as atherosclerosis and medial necrosis with aortic dilatation, valve incompetence and dissecting aneurysm; inflammatory diseases such as Takayasu arteritis, syphilis, giant cell and IgM4 aortitis; neoplasms; and trauma. Aortic homografts from cadavers, including both the sinus portion with semilunar cusps and the tubular portion, are surgically employed to replace a native sick ascending aorta. However, the antigenicity of allograft cells, in the lamellar units and interstitial cells in the cusps, is maintained. Thus, an immune reaction may occur, limiting durability. After proper decellularization and 6 months’ implantation in sheep, endogenous cell repopulation was shown to occur in both the valve and aortic wall, including the endothelium, without evidence of inflammation and structural deterioration/calcification in the mid-term. The allograft was transformed into an autograft.

Semilunar Valve Interventions for Congenital Heart Disease: JACC State-of-the-Art Review

Transcatheter balloon valvuloplasty for the treatment of aortic and pulmonary valve stenosis was first described nearly 40 years ago. Since that time, the technique has been refined in an effort to optimize acute outcomes while reducing the long-term need for reintervention and valve replacement. Balloon pulmonary valvuloplasty is considered first-line therapy for pulmonary valve stenosis and generally results in successful relief of valvar obstruction. Larger balloon to annulus (BAR) diameter ratios can increase the risk for significant valvar regurgitation. However, the development of regurgitation resulting in right ventricular dilation and dysfunction necessitating pulmonary valve replacement is uncommon in long-term follow-up. Balloon aortic valvuloplasty has generally been the first-line therapy for aortic valve stenosis, although some contemporary studies have documented improved outcomes following surgical valvuloplasty in a subset of patients who achieve tri-leaflet valve morphology following surgical repair. Over time, progressive aortic regurgitation is common and frequently results in the need for aortic valve replacement. Neonates with critical aortic valve stenosis remain a particularly high-risk group. More contemporary data suggest that acutely achieving an aortic valve gradient <35 mm Hg with mild aortic regurgitation may improve long-term valve performance and reduce the need for valve replacement. Continued study will help to further improve outcomes and reduce the need for future reinterventions.

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.

Bicuspid Aortic Valve Disease from Infancy to Older Age: A 25-Year Experience from an Italian Referral Center

Aim:

Bicuspid aortic valve (BAV) is the most common congenital heart defect, with considerable risk of morbidity and mortality. The purpose of the study was to analyze clinical and echocardiographic presentation of BAV in a large-volume tertiary Italian center and to test their interaction with full age span, sex, and first diagnosis versus second referral.

Methods:

Consecutive patients of all ages diagnosed with BAV at our center from January 1988 to December 2012 were retrospectively included. Exclusion criteria were as follows: associated complex congenital cardiac disease, systemic syndrome, and previous cardiac surgery.

Results:

Eligible patients were 790, divided by age quartiles. Seventy-two percent of patients had any grade BAV dysfunction. Aortic valve stenosis was more frequent in the first (24%) and fourth (24%) quartiles. This corresponds to a double-peak stenosis severity curve, being more severe at a very young age and in the elderly. Aortic valve regurgitation was more prevalent in each quartile than stenosis, with a prevalence of 72% in the second quartile and 77% in the third quartile. This corresponds to a single-peak regurgitation severity curve, being more severe in the fourth and fifth decades of life. Patients with previously diagnosed BAV had more significant valve dysfunction in comparison to patients with first diagnosis of BAV, either stenosis (15% vs. 21%, P = 0.024) or regurgitation (58% vs. 68%, P = 0.006).

Conclusion:

The dominant BAV dysfunction in this large Northern Italian community is regurgitation, with higher severity of disease in the fourth and fifth decades of life.

Transcatheter Aortic Valve Replacement in Bicuspid Aortic Valve Stenosis

After 15 years of successive randomized, controlled trials, indications for transcatheter aortic valve replacement (TAVR) are rapidly expanding. In the coming years, this procedure could become the first line treatment for patients with a symptomatic severe aortic stenosis and a tricuspid aortic valve anatomy. However, randomized, controlled trials have excluded bicuspid aortic valve (BAV), which is the most frequent congenital heart disease occurring in 1% to 2% of the total population and representing at least 25% of patients 80 years of age or older referred for aortic valve replacement. The use of a less invasive transcatheter therapy in this elderly population became rapidly attractive, and approximately 10% of patients currently undergoing TAVR have a BAV. The U.S. Food and Drug Administration and the "European Conformity" have approved TAVR for low-risk patients regardless of the aortic valve anatomy whereas international guidelines recommend surgical replacement in BAV populations. Given this progressive expansion of TAVR toward younger and lower-risk patients, heart teams are encountering BAV patients more frequently, while the ability of this therapy to treat such a challenging anatomy remains uncertain. This review will address the singularity of BAV anatomy and associated technical challenges for the TAVR procedure. We will examine and summarize available clinical evidence and highlight critical knowledge gaps regarding TAVR utilization in BAV patients. We will provide a comprehensive overview of the role of computed tomography scans in the diagnosis, and classification of BAV and TAVR procedure planning. Overall, we will offer an integrated framework for understanding the current role of TAVR in the treatment of bicuspid aortic stenosis and for guiding physicians in clinical decision-making.

Serial echocardiography for valve dysfunction and aortic dilation in bicuspid aortic valves

BACKGROUND AND AIMS

Complications of bicuspid aortic valve commonly include aortic stenosis, aortic regurgitation, and ascending aortic dilation. The progression of these lesions is not well described.

MATERIALS AND METHODS

We reviewed 249 bicuspid aortic valve patients with at least two echocardiograms from 2006 to 2016. Valve morphology (right-left or right-noncoronary cusp fusion) was confirmed by visual inspection, and aortic stenosis and regurgitation were quantified according to current guidelines; the ascending aorta was measured at end-systole 2-3 cm above the sinotubular junction. Annualized progression of stenosis, regurgitation, and aortic dilation from first to most recent echocardiogram were compared between right-left and right-nonfused valves using multivariable logistic regression to adjust for baseline differences in groups.

RESULTS

Among 249 bicuspid aortic valve patients (mean age 47.6 ± 13.5 years, 66.3% male), 75.9% had right-left cusp fusion. At baseline, aortic stenosis was absent or mild in 80.3%; aortic regurgitation was absent or mild in 80.7%; and aortic diameters were 35.0 ± 5.7 mm (sinuses of Valsalva) and 37.4 ± 6.2 mm (ascending). Mean annualized decrease in aortic valve area was 0.07 cm² /year, with 30% of bicuspid aortic valve patients progressing ≥0.1 cm² /year. Aortic regurgitation progressed ≥1 grade in 37 patients. Mean annualized increase in ascending aorta diameter was 0.36 mm/year in right-left and 0.65 mm/year in right-nonbicuspid valves.

CONCLUSIONS

In this serial echocardiographic study of bicuspid aortic valve patients, cusp orientation was not associated with progression of valve dysfunction. Right-noncoronary cusp fusion was associated with ascending aortic diameter progression.

Bicuspid aortic valve and sports: From the echocardiographic evaluation to the eligibility for sports competition

Bicuspid aortic valve (BAV) is the most common congenital heart defect in adults. Although a BAV may remain without clinical consequences for a lifetime, it can deteriorate in aortic valve stenosis and regurgitation and aortic dilatation. Unfortunately, the impact of regular training on patients with BAV and its natural course is not fully understood, although preliminary evidence suggests that the progression of valvular disease occurs primarily in an independent manner from sports practice. The current review aims to report how to perform a comprehensive echocardiographic examination in athletes with BAV and analyze the current literature on the influence of sports practice and how it impacts the aortic valve in athletes with BAV. The article also summarizes the current recommendations on sports eligibility and disqualification for competitive athletes with BAV.

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.

Utilizing wall shear stress as a clinical biomarker for bicuspid valve-associated aortopathy

PURPOSE OF REVIEW

Bicuspid aortic valve (BAV) results from fusion of two adjacent aortic valve cusps, and is associated with dilatation of the aorta, known as BAV-associated aortopathy, or bicuspid aortopathy. Bicuspid aortopathy is progressive, increasing the risk of life-threatening clinical events, such as aortic dissection. Regular monitoring and timely intervention with prophylactic surgical resection of the proximal aorta is recommended.

RECENT FINDINGS

Aortopathy is heterogeneous among patients. Studies have shown that different flow patterns lead to specific phenotypes of aortopathy. Although not uniform, BAV morphology affects flow patterns. Recent work has demonstrated the role of wall shear stress (WSS) in driving aortopathy, and it is suggested that individualized WSS 'heat maps' can be used for clinically monitoring patients with BAV. WSS has the potential to be an imaging biomarker for directing resection timing, surgical strategies, and postsurgical follow-up care.

SUMMARY

Finding and validating noninvasive hemodynamic biomarkers of aortic risk to assist in the management of BAV patients is of clinical importance. Herein, we will review the latest findings pertaining to the utility of WSS as a specific biomarker of risk for BAV patients with aortopathy.

The American Association for Thoracic Surgery consensus guidelines on bicuspid aortic valve-related aortopathy: Full online-only version

Bicuspid aortic valve disease is the most common congenital cardiac disorder, being present in 1% to 2% of the general population. Associated aortopathy is a common finding in patients with bicuspid aortic valve disease, with thoracic aortic dilation noted in approximately 40% of patients in referral centers. Several previous consensus statements and guidelines have addressed the management of bicuspid aortic valve-associated aortopathy, but none focused entirely on this disease process. The current guidelines cover all major aspects of bicuspid aortic valve aortopathy, including natural history, phenotypic expression, histology and molecular pathomechanisms, imaging, indications for surgery, surveillance, and follow-up, and recommendations for future research. It is intended to provide clinicians with a current and comprehensive review of bicuspid aortic valve aortopathy and to guide the daily management of these complex patients.

GATA6 Regulates Aortic Valve Remodeling, and Its Haploinsufficiency Leads to Right-Left Type Bicuspid Aortic Valve

BACKGROUND

Bicuspid aortic valve (BAV), the most common congenital heart defect affecting 1% to 2% of the population, is a major risk factor for premature aortic valve disease and accounts for the majority of valve replacement. The genetic basis and mechanisms of BAV etiology and pathogenesis remain largely undefined.

METHODS

Cardiac structure and function was assessed in mice lacking a Gata6 allele. Human GATA6 gene variants were analyzed in 452 BAV cases from the BAV consortium and 1849 controls from the Framingham GWAS (Genome Wide Association Study). GATA6 expression was determined in mice and human tissues using quantitative real-time polymerase chain reaction and immunohistochemistry. Mechanistic studies were carried out in cultured cells.

RESULTS

Gata6 heterozygous mice have highly penetrant right-left (RL)-type BAV, the most frequent type in humans. GATA6 transcript levels are lower in human BAV compared with normal tricuspid valves. Mechanistically, Gata6 haploinsufficiency disrupts valve remodeling and extracellular matrix composition through dysregulation of important signaling molecules, including matrix metalloproteinase 9. Cell-specific inactivation of Gata6 reveals an essential role for GATA6 in secondary heart field myocytes because loss of 1 Gata6 allele from Isl- 1-positive cells-but not from endothelial or neural crest cells-recapitulates the phenotype of Gata6 heterozygous mice.

CONCLUSIONS

The data identify a new cellular and molecular mechanism underlying BAV. The availability of an animal model for the most frequent human BAV opens the way for the elucidation of BAV pathogenesis and the development of much needed therapies.

Evaluation of relationship between bicuspid aortic valve phenotype with valve dysfunction and associated aortopathy

Introduction: Morphology of bicuspid aortic valve (BAV) may have implication in the associated pathologies including aortic stenosis (AS), aortic insufficiency (AI) and aortic dilation. The aim of this study is to investigate the frequency and patterns of valvular dysfunction and aortopathy associated with different phenotypes of BAV in a referral center in northwest of Iran. Methods: In this prospective study patients who presented to our echocardiography lab between January 2014 and December 2015 and were diagnosed with BAV were assessed. Frequency of various BAV phenotypes and their association with valvular dysfunction and aortopathy was evaluated. A P value less than 0.05 was considered statistically significant. Results: The average age of the study patients was 40±16 years, with predominance of male sex (72%). Patients with anteroposteriorly located BAV (BAV-AP) phenotype constituted majority of our cases with prevalence of 62.7%, while 37.3% of cases had right-left (BAV-RL) located valves. BAV-RL patients when compared to BAV-AP patients had higher frequencies of dilated aortic arch (25% vs. 4.3%, P < 0.001), AS (56.3% vs. 31.4%, P < 0.001), mass or vegetation on aortic valve (14.3 vs. 6.4%, P = 0.023) and lower frequencies of dilated aortic root (42.9% vs. 57.4%, P = 0.01), aortic insufficiency (68.8% vs. 79.8%, P = 0.034) and co-arctation of aorta (3.6% vs. 11.7%, P = 0.01). Conclusion: There seems to be a relationship between various BAV phenotypes, and frequency and pattern of aortic valve dysfunction and aortopathy. These findings suggest that examining leaflet morphology in BAV might help in risk stratification of these patients.

Aortic elasticity and the influence of valve morphology in children with bicuspid aortic valve

AimWe investigated dimensions and elasticity of whole aorta in patients with bicuspid aortic valve and influence of valve phenotype.

METHOD

The study group included 44 patients and 42 controls. Patients were divided into groups according to the type of valve opening as horizontal - fusion between right and left coronary cusps - and vertical - fusion between right-non-coronary cusps; according to age they were divided into younger (5-10 years) and older patients (11-16 years). Our study did not include valve phenotype with fusion between left and non-coronary cusps. Systolic-diastolic diameters of aortic annulus, sinus valsalva, sinutubular junction, arcus, and ascending-descending and abdominal aorta were measured and z-scores were obtained. Aortic strain, distensibility, and stiffness index were calculated. Flow-mediated dilatation of brachial artery was studied.

RESULTS

z-Scores at annulus, sinus valsalva, sinutubular junction, and ascending aorta were higher in study patients (p=0.001, p=0.0001, p=0.0001, p=0.0001, respectively). z-Scores of sinus valsalva and sinotubular junction were higher in the horizontal group than in the vertical group (p=0.006, p=0.023, respectively). z-Score was over +2 in 51% of patients with horizontal morphology and 33% of patients with vertical morphology (p=0.0001). Ascending aorta was more distensible and less stiff in the study group (11.3±5.63 versus 7.91±4.5, p=0.002; 4.76±3.60 versus 6.19±3.44 cm2.dyn-1.10-6, p=0.033, respectively). Stiffness index of ascending, arcus, and abdominal aorta were higher in the horizontal group (p=0.004, p=0.038, p=0.006, respectively). Ascending aorta was more distensible and less stiff in the younger group (p=0.007, p=0.027, respectively) but did not differ in the older group compared with the control group.

CONCLUSION

Aortic dimensions are enlarged in patients with bicuspid aortic valve starting from childhood, suggesting the presence of generalised aortopathy. Aortic elasticity is increased at young age and decreased with age.

Exercise recommendations in patients with valvular heart disease

Valvular heart disease affects 1%-2% of young individuals, many of whom aspire to partake in competitive sport or high intensity recreational exercise. There are limited reports on the impact of intensive physical activity on the progression of valvular heart disease; therefore, current recommendations are based on consensus opinion. The management of exercising individuals with valvular heart disease requires a structured approach that incorporates several key factors including symptomatic status, functional capacity, type and nature of the valvular lesion, impact on ventricular structure and function and effect on pulmonary artery pressure. Asymptomatic individuals with minor valvular abnormalities may engage in all forms of competitive sport, whereas those with lesions of moderate severity may exercise intensively if an exercise stress test tailored to the relevant physical activity reveals good functional capacity without myocardial ischaemia, haemodynamic disturbances or arrhythmia. Symptomatic athletes and those with severe valvular heart disease, impaired ventricular function, pulmonary hypertension and arrhythmias should refrain from most competitive sports. Athletes with a bicuspid aortic valve and aortic root diameter >40 mm should avoid sport with a strong isometric component even with minimal valvular dysfunction. There is an association between mitral valve prolapse and sudden cardiac death in the general population; however, there is limited evidence of increased risk with competitive sport. Athletes undergoing corrective surgery may return to exercise after 3 months if ventricular function and exercise capacity are preserved. Individuals anticoagulated for mechanical bioprosthetic valves should avoid contact or collision sport to minimise the risk of bleeding.

Abnormal aortic stiffness in patients with bicuspid aortic valve: phenotypic variation determined by magnetic resonance imaging

The aim of this study was to assess aortic stiffness in patients with bicuspid aortic valve (BAV), and to determine if differences exist among the BAV phenotypes. Stiffness was measured by pulse wave velocity (PWV) determined using velocity-encoded magnetic resonance imaging (VENC-MRI). VENC-MRI was performed in 100 BAV patients and 45 normal controls. PWV was determined between the mid ascending and mid descending aorta. The BAV phenotypes were characterized using steady-state free precession (SSFP) images acquired across the face of the aortic valve, and classified as follows: right-left cusp (R-L) fusion, right and non-coronary cusp (R-NC) fusion, and left and non-coronary cusp (L-NC) fusion. The following BAV phenotypes were identified: 76 R-L, 23 R-NC, and 1 L-NC fusion. BAV patients demonstrated significantly greater PWV compared to normal controls, after adjusting for age (9.16 vs. 3.83 m/s; p < 0.0001). Furthermore, PWV was significantly greater in patients with R-NC fusion than those with R-L fusion phenotype (12.27 vs. 7.97 m/s; p < 0.001). There was significantly increased PWV from VENC-MRI in BAV patients compared to normal controls. Thisis the first to demonstrate the association of different BAV phenotypes and aortic stiffness. VENC-MRI PWV assessment potentially represents a novel parameter for enhanced surveillance and may alter surgical triage of aorta in this high risk group.

Echocardiographic manifestations and chemical composition of stenotic bicuspid aortic valves

Bicuspid aortic valve (BAV) is an inherited form of heart disease with only two aortic valve leaflets via a disorder of cardiac valvulogenesis. We investigated the in vivo echocardiographic features of cardiac morphology in patients with BAV and the ex vivo compositional components of all the excised BAV leaflets isolated from BAV patients. Three BAV patients were randomly selected. All patients underwent 2D transthoracic echocardiography (TTE) with a Doppler ultrasound tool. The compositional components of each respective BAV leaflet for all the excised BAVs were determined by a portable fiber-optic Raman spectroscopy. Preoperative TTE revealed the thickened and calcified BAV leaflets, and stenotic aortic flow for all BAV patients. These BAV patients exhibited severe aortic stenosis (AS) by the lower values of aortic valve area (AVA) index. One patient showed a more significant left ventricle hypertrophy, whereas two patients exhibited a significant aortic regurgitation (AR). In addition, three different Raman spectral patterns were summed up from 121 randomized Raman determinations for all the excised BAV leaflets. The main calcified deposition in each BAV leaflet was formed by large amounts of calcium hydroxyapatite and type-B carbonate apatite (Raman bands at 960 and 1070 cm^-1). The calcified BAV leaflets were composed of different compositional components such as calcium hydroxyapatite, type-B carbonate apatite, lipids, proteins, cholesterol and β-carotene. The rare NL subtype of type 1 BAV morphotype was found in one patient, but two patients had the purely BAV morphotype with two equal-sized leaflets.

Longitudinal Assessment of the Doppler-Estimated Maximum Gradient in Patients With Congenital Valvar Aortic Stenosis Pre- and Post-Balloon Valvuloplasty

BACKGROUND

Aortic stenosis has been reported to manifest a slow rate of progression in mild disease, with a greater likelihood of progression in patients with moderate-severe disease. The natural history of the Doppler-estimated maximum gradient (DEMG) in patients after balloon aortic valvuloplasty (BAVP) has not previously been studied on a large scale.

METHODS AND RESULTS

A retrospective review was performed of 360 patients from 1984 to 2012 with aortic stenosis, providing a total of 2059 echocardiograms both before and after BAVP. Patients were excluded if they had an intervention within the first 30 days of life. The relationships between the aortic stenosis DEMG and several predictors (age at initial study, body surface area, valve morphology, and initial DEMG) were explored using linear mixed effect models. Patients with a unicommissural aortic valve had a significantly higher rate of progression compared with those with a bicommissural aortic valve (0.81 and 0.45 mm Hg/year; P<0.001). The median rate of progression in the post-BAVP group was significantly lower than the median pre-BAVP rate of progression (n=34; pre-BAVP 3.97 [1.69-8.7] mm Hg/year; post-BAVP 0.40 [-1.80 to 3.88] mm Hg/year; P<0.008). When adjusted for body surface area, there was no significant increase in the DEMG (-0.03 mm Hg/m² per year; P<0.001).

CONCLUSIONS

There is a statistically significant increase in the DEMG over time in patients with aortic stenosis. After balloon dilation, the DEMG rate of change is reduced compared with that pre-dilation. Given the effect of body surface area on DEMG progression, more frequent observation should be made during periods of rapid somatic growth.

Impact of Bicuspid Aortic Valve Morphology on Aortic Valve Disease and Aortic Dilation in Pediatric Patients

Bicuspid aortic valve (BAV) is the most common congenital heart defect. BAV is associated with aortic stenosis and insufficiency, and aortic dilation in adult groups, but data in pediatric groups are limited. We sought to assess the impact of BAV morphology on aortic valve disease and aortic dilation in pediatric patients. We performed a retrospective review of all echocardiograms in patients with isolated BAV who were followed at our institution from July 2002 to July 2012. BAV morphology, aortic valve stenosis and/or insufficiency, and aortic dimensions were measured manually. Comparisons were made between right-left cusp fusion (RL) and right-noncoronary cusp fusion (RN) BAV morphologies. Generalized least square models were fit to analyze the impact of specific variables on aortic dilation. There were 1075 echocardiograms in 366 patients (72% male) with isolated BAV. Aortic valve insufficiency and stenosis were more common in RN (p < 0.001 for both). The median aortic sinus Z score was higher in the RL (0.47; IQR - 0.31 to 1.44) than in the RN group (0.02; - 0.83 to 0.82) (p < 0.001). There was no difference in median ascending aorta Z score between groups. Patients with the highest weights had larger aortas (p < 0.001), but the absolute difference between the highest and lowest weight groups was small (1.5 mm). The impact of BAV morphology on aortic valve disease and aortic dilation in pediatric patients presages that seen in adults. Patient body weight does not make significant clinical impacts on aortic diameters, suggesting that Z scores for aortic diameters should be based on ideal body weights.

Aortic Diameter Growth in Children With a Bicuspid Aortic Valve

Knowledge of aortic growth in patients with bicuspid aortic valve (BAV) is essential to identify patients at risk for dissection, but data on children remain unclear. We retrospectively evaluated the aortic diameters of all pediatric BAV patients, identified through an echocardiographic database (2005 to 2013). Medical records were reviewed and aortic diameters re-measured on echocardiographic images at diagnosis and if available on variable mid- and endpoints follow-up. Dilatation (z-score >2) was based on 2 different z-score equation methods (Gautier/Campens). In 234 of the total 250 BAV patients, aortic diameters were analyzed; median age was 6.1 years (interquartile range 1.7 to 10), of which 63% were male. Aortic coarctation was present in 81 (36%) patients, 23% had a ventricular septal defect. BAV morphology according to Sievers was as follows: type 0 in 128 patients (55%), type 1 in 96 (41%), and type 2 in 10 (4%). Ascending aortic (AA) dilatation was present in 24% (Gautier) and 36% (Campens) at inclusion. Median follow-up was 4.7 years. The AA was the only location where mean z-scores progressed significantly with age: 0.06 (Gautier) and 0.09 (Campens) units per year between ages 5 and 15 years. Associations for higher AA z-scores at older age were an initial z-score >2 (p <0.001) and aortic valve stenosis (p <0.05). Neither dissection nor preventive aortic surgery occurred. In conclusion, only the AA seems at risk for complication, although no aortic complications occurred in this pediatric BAV cohort. BAV morphology seems associated with larger AA z-scores and valvular dysfunction.

Managing Thoracic Aortic Aneurysm in Patients with Bicuspid Aortic Valve Based on Aortic Root-Involvement

Bicuspid aortic valve (BAV) can be both sporadic and hereditary, is phenotypically variable, and genetically heterogeneous. The clinical presentation of BAV is diverse and commonly associated with a high prevalence of valvular dysfunction producing altered hemodynamics and aortic abnormalities (e.g., aneurysm and dissection). The thoracic aortic aneurysm (TAA) in BAV frequently involves the proximal aorta, including the aortic root, ascending aorta, and aortic arch, but spares the aorta distal to the aortic arch. While the ascending aortic aneurysm might be affected by both aortopathy and hemodynamics, the aortic root aneurysm is considered to be more of a consequence of aortopathy rather than hemodynamics, especially in younger patients. The management of aortic aneurysm in BAV has been very controversial because the molecular mechanism is unknown. Increasing evidence points toward the BAV root phenotype [aortic root dilation with aortic insufficiency (AI)] as having a higher risk of catastrophic aortic complications. We propose more aggressive surgical approaches toward the BAV with root phenotype.

Pathological Investigation of Congenital Bicuspid Aortic Valve Stenosis, Compared with Atherosclerotic Tricuspid Aortic Valve Stenosis and Congenital Bicuspid Aortic Valve Regurgitation

Background

Congenital bicuspid aortic valve (CBAV) is the main cause of aortic stenosis (AS) in young adults. However, the histopathological features of AS in patients with CBAV have not been fully investigated.

Methods and Results

We examined specimens of aortic valve leaflets obtained from patients who had undergone aortic valve re/placement at our institution for severe AS with CBAV (n = 24, CBAV-AS group), severe AS with tricuspid aortic valve (n = 24, TAV-AS group), and severe aortic regurgitation (AR) with CBAV (n = 24, CBAV-AR group). We compared the histopathological features among the three groups. Pathological features were classified using semi-quantitative methods (graded on a scale 0 to 3) by experienced pathologists without knowledge of the patients’ backgrounds. The severity of inflammation, neovascularization, and calcium and cholesterol deposition did not differ between the CBAV-AS and TAV-AS groups, and these four parameters were less marked in the CBAV-AR group than in the CBAV-AS (all p<0.01). Meanwhile, the grade of valvular fibrosis was greater in the CBAV-AS group, compared with the TAV-AS and CBAV-AR groups (both p<0.01). In AS patients, thickness of fibrotic lesions was greater on the aortic side than on the ventricular side (both p<0.01). Meanwhile, thickness of fibrotic lesions was comparable between the aortic and ventricular sides in CBAV-AR patients (p = 0.35).

Conclusions

Valvular fibrosis, especially on the aortic side, was greater in patients with CBAV-AS than in those without, suggesting a difference in the pathogenesis of AS between CBAV and TAV.