Retrospective study to identify predictors of the presence and rapid progression of aortic dilatation in patients with bicuspid aortic valves

Concomitant cardiovascular malformations in isolated bicuspid aortic valve disease: a retrospective cross-sectional study and meta-analysis

Background

Congenital bicuspid aortic valve affects up to 2% of the general population. It occurs in complex congenital heart defects or in syndromes such as Turner, Marfan, or Loeys-Dietz. However, the majority of bicuspid aortic valves are considered to manifest as isolated malformations.

Methods

We aimed to assess retrospectively associated cardiovascular malformations in 200 individuals with bicuspid aortic valve considered to occur as an isolated manifestation. All individuals underwent transthoracic echocardiography, 164 thoracoabdominal tomographic imaging, and 84 coronary artery imaging. In addition, we also performed a meta-analysis of data from the literature to assess the occurrence of associate malformations.

Results

In our retrospective cross-sectional study collective, the mean age was 45±15 years, 154 (77%) individuals were male. Anatomy of bicuspid aortic valve according to Schaefer was type 1 in 142 (71%), type 2 in 35 (18%), type 3 in 2 (1%), unicuspid in 6 (3%), and unclassified in 15 (8%) individuals. Coarctation of the aorta had 4.2% of individuals, 3.6% had coronary anomalies. No individual had a patent ductus arteriosus, 0.5% had atrial and ventricular septal defect each, 1.5% mitral valve prolapse. No individual had a tricuspid valve prolapse. Our meta-analysis identified in cohorts with isolated bicuspid aortic valve 11.8% (95% CI: 7.7–16.0%) individuals with aortic coarctation, 3.7% (95% CI: 1.2–6.1%) with coronary anomalies, 3.3% (95% CI: 0.0–6.7%) with patent ductus arteriosus, 5.9% (95% CI: 1.3–10.5%) with ventricular septal defect and 1.6% (95% CI: 1.1–2.1%) with mitral valve prolapse.

Conclusions

Individuals with isolated bicuspid aortic valve may exhibit a variety of associated cardiovascular malformations and therefore screening for associated malformations may be warranted.

Bicuspid Aortic Valves: an Up-to-Date Review on Genetics, Natural History, and Management

PURPOSE OF REVIEW

Bicuspid aortic valve (BAV) is the most common congenital cardiac abnormality. It has a wide spectrum of clinical manifestations including aortic regurgitation (AR), aortic stenosis, and an associated aortopathy with a small but increased risk of aortic dissection. This review describes current knowledge of BAV, from anatomy and genetics to a discussion of multifaceted strategies utilized in the management of this unique patient population. This review will also highlight critical knowledge gaps in areas of basic and clinical research to enhance further understanding of this clinical entity.

RECENT FINDINGS

The current knowledge regarding pathophysiologic mechanisms, screening, and surveillance guidelines for BAV and the associated aortopathy is discussed. We also discuss current management techniques for aortic valve repair versus replacement, indications for aortic surgery (root or ascending aorta), and the emergence of the Ross procedure as a viable management option not only in children, but also in adolescents and adults. The varied clinical phenotype of the BAV, resulting in its specific complex hemodynamic interactions, renders it an entity which is separate and distinct from the tricuspid aortic valve pathologies. While various aortic histopathologic and protein alterations in BAV patients have been described, it remains unclear if these changes are causal or the result of hemodynamic alterations imposed by sheer stress on the intrinsically dysfunctional BAV. Medical management for patients with BAV with AS, AI, or dilated aortic roots/ascending aortas remains challenging and needs further investigation. More than 50% of patients with BAV will undergo AVR during their lifetime, and more than 25% of patients with BAV undergo aortic surgery performed for dilation of the aortic root or ascending aorta, often concurrently with AVR. The search for the ultimate genetic or epigenetic cause of the different bicuspid phenotypes will ultimately be facilitated by the next-generation sequencing tools that allow for study of large populations at low cost. Improvements in diagnostic and stratification criteria to accurately risk assess BAV patients are critical to this process.

Point on the Aortic Bicuspid Valve

Background—Bicuspid aortic valve (BAV) disease is the most prevalent congenital heart disease in the world. Knowledge about its subtypes origin, development, and evolution is poor despite the frequency and the potential gravity of this condition. Its prognosis mostly depends on the risk of aortic aneurysm development with an increased risk of aortic dissection. Aims—This review aims to describe this complex pathology in way to improve the bicuspid patients’ management. Study design—We reviewed the literature with MEDLINE and EMBASE databases using MeSH terms such as “bicuspid aortic valve”, “ascending aorta”, and “bicuspid classification”. Results—There are various classifications. They depend on the criteria chosen by the authors to differentiate subtypes. Those criteria can be the number and position of the raphes, the cusps, the commissures, or their arrangements regarding coronary ostia. Sievers’ classification is the reference. The phenotypic description of embryology revealed that all subtypes of BAV are the results of different embryological pathogenesis, and therefore, should be considered as distinct conditions. Their common development towards aortic dilatation is explained by the aortic media’s pathological histology with cystic medial necrosis. At the opposite, BAV seems to display a profound genetic heterogeneity with both sporadic and familial forms. BAV can be even isolated or combined with other congenital malformations. Conclusions—All those characteristics make this pathology a highly complex condition that needs further genetic, embryological, and hemodynamic explorations to complete its well described anatomy.

Unraveling Bicuspid Aortic Valve Enigmas by Multimodality Imaging: Clinical Implications

Multimodality imaging is the basis of the diagnosis, follow-up, and surgical management of bicuspid aortic valve (BAV) patients. Transthoracic echocardiography (TTE) is used in our clinical routine practice as a first line imaging for BAV diagnosis, valvular phenotyping and function, measurement of thoracic aorta, exclusion of other aortic malformations, and for the assessment of complications such are infective endocarditis and aortic. Nevertheless, TTE is less useful if we want to assess accurately other aortic segments such as mid-distal ascending aorta, where computed tomography (CT) and magnetic resonance (CMR) could improve the precision of aorta size measurement by multiplanar reconstructions. A major advantage of CT is its superior spatial resolution, which affords a better definition of valve morphology and calcification, accuracy, and reproducibility of ascending aorta size, and allows for coronary artery assessment. Moreover, CMR offers the opportunity of being able to evaluate aortic functional properties and blood flow patterns. In this setting, new developed sequences such as 4D-flow may provide new parameters to predict events during follow up. The integration of all multimodality information facilitates a comprehensive evaluation of morphologic and dynamic features, stratification of the risk, and therapy guidance of this cohort of patients.

Inter-Ethnic Differences in Valvular Dysfunction, Aortopathy, and Progression of Disease of an Asian Bicuspid Aortic Valve Population

BACKGROUND

There are differences in bicuspid aortic valve (BAV) characteristics between Asian and European populations, but little is known about the inter-ethnic differences in bicuspid valve function and aortic root dimensions within the diverse Asian population.

METHODS

From 1992-2017, 562 patients with index echocardiographic diagnosis of BAV in a tertiary health care institution in Singapore were analysed according to their ethnic groups: Chinese, Malay, Indian, and Eurasian. Study outcomes included BAV complications (infective endocarditis, aortic dissection) and clinical outcomes (aortic valve surgery, aortic root surgery, all-cause mortality). Total events were defined as composite outcome of all BAV complications and outcomes. Aortic dimensions and aortic dilatation rates were also studied.

RESULTS

There were 379 (67.5%) Chinese, 79 (14.0%) Malay, 73 (13.0%) Indian, and 31 (5.5%) Eurasian patients. Type 1 BAV (58.5%) was the most prevalent BAV morphology, with moderate-to-severe aortic stenosis (AS) (36.8%) being the most common complication in the overall population. There was a higher prevalence of type 0 BAV in Chinese and Indian groups, and type 1 BAV with fusion of left-right coronary cusp in Eurasian and Malay groups (p=0.082). There was no difference in significant AS among groups. The highest prevalence of moderate-to-severe aortic regurgitation was observed amongst the Eurasian group, followed by Chinese, Indian, and Malay groups (p=0.033). The Chinese group had the largest mean indexed diameters of the aortic root. Multivariable linear regression demonstrated that only the Chinese had significantly larger indexed diameters in the aortic annulus, sinotubular junction (STJ), and ascending aorta (AA), relative to the Eurasian group, after adjusting for age, sex, smoking, hypertension, hyperlipidaemia, diabetes, and aortic regurgitation. On follow-up echocardiography, there was a trend towards the highest dilatation rates of sinus of Valsalva and STJ amongst Indian, and AA amongst Malay groups. Kaplan-Meier curves showed the highest incidence of total events amongst Chinese, followed by Malay, Indian and Eurasian (log-rank=9.691; p=0.021) patients.

CONCLUSION

There were differences in BAV morphology, valve dysfunction, aortopathy, and prognosis within the Asian population. Chinese patients had one of the highest prevalence of significant aortic regurgitation, with the largest aortic dimensions and worst outcomes compared with other Asian ethnicities. Closer surveillance is warranted in BAV patients within the Asian population.

Bicuspid aortic valve repair with external or subcommissural annuloplasty-echocardiographic prospective trial

BACKGROUND

The incompetent bicuspid aortic valve (BAV) can be repaired using various techniques. This study presents a prospective comparison of external and subcommissural aortic annuloplasty.

METHODS

Fifty consecutive patients (38 males, age: 43.9 ± 15.8 years) with BAV insufficiency with or without aortic dilatation underwent valve repair in a single institution. They were prospectively allocated to one of two groups based on the aortic annulus stabilization technique: 25 patients were operated on using the subcommissural annuloplasty (SCA) and 25 using the external complete annuloplasty (EA). Transthoracic echocardiography was performed in all patients before the operation and 1 and 3 years after the operation. Moreover, mortality and morbidity at 7 years were evaluated.

RESULTS

In prospective echocardiographic comparison, EA was associated with smaller diameter of the aortic annulus (24.1 ± 2.6 mm vs. 25.8±2.1 mm, p < .05) and lower mean and peak transvalvular gradients (7 ± 4 mmHg vs. 13 ± 4 mmHg, p = .02 and 15.3 ± 9.7 mmHg vs. 20.7 ± 5.6 mmHg, p = .03, respectively). No patients died or required reoperation due to recurrent insufficiency at 6,81 (interquartile range-0,17) years after the operation. The Kaplan-Meier actuarial freedom from aortic regurgitation (AR) grade ≥2 or gradient > 20 mmHg at 35.1 ± 3.6 months years was 96% (24 out of 25) for patients who had external annuloplasty and amounted to 76% (19 out of 25) for those who had SCA, p = .05).

CONCLUSIONS

External annuloplasty performed during repair of the BAV is associated with better hemodynamics at medium-term follow-up compared to SCA.

Wall Shear Stress Predicts Aortic Dilation in Patients With Bicuspid Aortic Valve

OBJECTIVES

This study sought to assess the predictive value of wall shear stress (WSS) for colocalized ascending aorta (AAo) growth rate (GR) in patients with bicuspid aortic valve (BAV).

BACKGROUND

BAV is associated with AAo dilation, but there is limited knowledge about possible predictors of aortic dilation in BAV patients with BAV. An increased WSS has been related to aortic wall damage in patients with BAV, but no previous prospective study tested its predictive value for dilation rate. Recently, a registration-based technique for the semiautomatic mapping of aortic GR has been presented and validated.

METHODS

Forty-seven patients with BAV free from valvular dysfunction prospectively underwent 4-dimensional flow cardiac magnetic resonance to compute WSS and subsequent follow-up with 2 electrocardiogram-gated high-resolution contrast-enhanced computed tomography angiograms for GR assessment.

RESULTS

During a median follow-up duration of 43 months, mid AAo GR was 0.24 mm/year. WSS and its circumferential component showed statistically significant association with mid AAo GR in bivariate (P = 0.049 and P = 0.014, respectively) and in multivariate analysis corrected for stroke volume and either baseline AAo diameter (P = 0.046 and P = 0.014, respectively) or z-score (P = 0.036 and P = 0.012, respectively). GR mapping further detailed that GR was heterogeneous in the AAo and that circumferential WSS, but not WSS magnitude, showed statistically significant positive associations with GR in the regions with the fastest growth.

CONCLUSIONS

4D flow cardiac magnetic resonance-derived WSS and, in particular, its circumferential component predict progressive dilation of the ascending aorta in patients with BAV. Thus, the assessment of WSS may be considered in the follow-up of these patients.

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.

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.

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.

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.

Aortic Dilatation in Patients With Bicuspid Aortic Valve

Bicuspid aortic valve (BAV) is the most common congenital cardiac abnormality. BAV aortic dilatation is associated with an increased risk of adverse aortic events and represents a potentially lethal disease and hence a considerable medical burden. BAV with aortic dilatation warrants frequent monitoring, and elective surgical intervention is the only effective method to prevent dissection or rupture. The predictive value of the aortic diameter is known to be limited. The aortic diameter is presently still the main reference standard for surgical intervention owing to the lack of a comprehensive understanding of BAV aortopathy progression. This article provides a brief comprehensive review of the current knowledge on BAV aortopathy regarding clinical definitions, epidemiology, natural course, and pathophysiology, as well as hemodynamic and clinically significant aspects on the basis of the limited data available.

Assessing the methodology used to study the ascending aorta haemodynamics in bicuspid aortic valve

Aims

Modern imaging techniques provide evermore-detailed anatomical and physiological information for use in computational fluid dynamics to predict the behaviour of physiological phenomena. Computer modelling can help plan suitable interventions. Our group used magnetic resonance imaging and computational fluid dynamics to study the haemodynamic variables in the ascending aorta in patients with bicuspid aortic valve before and after isolated tissue aortic valve replacement. Computer modelling requires turning a physiological model into a mathematical one, solvable by equations that undergo multiple iterations in four dimensions. Creating these models involves several steps with manual inputs, making the process prone to errors and limiting its inter- and intra-operator reproducibility. Despite these challenges, we created computational models for each patient to study ascending aorta blood flow before and after surgery.

Methods and results

Magnetic resonance imaging provided the anatomical and velocity data required for the blood flow simulation. Patient-specific in- and outflow boundary conditions were used for the computational fluid dynamics analysis. Haemodynamic variables pertaining to blood flow pattern and derived from the magnetic resonance imaging data were calculated. However, we encountered problems in our multi-step methodology, most notably processing the flow data. This meant that other variables requiring computation with computational fluid dynamics could not be calculated.

Conclusion

Creating a model for computational fluid dynamics analysis is as complex as the physiology under scrutiny. We discuss some of the difficulties associated with creating such models, along with suggestions for improvements in order to yield reliable and beneficial results.

Non-aneurysmal ascending aorta diameter changes after aortic valve replacement in patients with stenotic bicuspid and tricuspid aortic valve

OBJECTIVE

The appropriate timing of aortic repair in patients with bicuspid aortic valve-related aortopathy remains controversial. We describe the changes in diameter of the non-aneurysmal ascending aorta after aortic valve replacement for bicuspid or tricuspid aortic valve stenosis.

METHODS

This retrospective review included 189 patients who had undergone aortic valve replacement for severe stenotic aortic valve with a non-aneurysmal ascending aorta diameter of 45 mm or less between January 2008 and December 2018. A linear mixed-effect model was used to analyze and compare the enlargement rates of the non-aneurysmal ascending aorta at the tubular portion after aortic valve replacement in bicuspid and tricuspid aortic valve patients.

RESULTS

The enlargement rate of the non-aneurysmal ascending aorta after aortic valve replacement was significantly greater in the bicuspid aortic valve group than in the tricuspid aortic valve group (0.36 mm/year vs. 0.09 mm/year, p < 0.001). The specific form of bicuspid aortic valve also affected aorta diameter enlargement: the enlargement rate of 0.85 mm/year in the Type 0 (according to Sievers' classification) group was approximately five times that in the Non-Type 0 group (p < 0.001). No aortic events were observed, and no patients needed reoperations for the ascending aorta, in either the bicuspid or tricuspid aortic valve groups.

CONCLUSION

The persistent possibility of progressive ascending aortic dilatation after aortic valve replacement for bicuspid aortic valve stenosis, especially in Type 0 bicuspid aortic valve patients, demands careful post-procedural evaluation of the ascending aorta.

High prevalence of ascending aortic dilation in adults with repaired coarctation of the aorta

BACKGROUND

Ascending aortic dilation is a feared complication in adults with repaired coarctation of the aorta, as the condition is associated with life-threatening complications such as aortic dissection and rupture. However, the data are currently limited regarding factors associated with ascending aortic dilation in these patients.

METHODS AND RESULTS

From the national register of congenital heart disease, 165 adult patients (≥ 18 years old) with repaired coarctation of the aorta, and echocardiographic data on aortic dimensions, were identified (61.2% male, mean age 35.8 ± 14.5 years). Aortic dilation (aortic diameters > 2 SD above reference mean) was found in 55 (33.3%) of the 165 included patients, and was associated with manifest aortic valve disease in univariable logistic regression analysis (OR 2.44, 95% CI [1.23, 4.83]).

CONCLUSIONS

Aortic dilation is common post-repair of coarctation of the aorta, and is associated with manifest aortic valve disease and thus indirectly with the presence of a bicuspid aortic valve. However, no association was found between aortic dilation and age or blood pressure.

The Association between Morphological and Functional Characteristics of the Bicuspid Aortic Valve and Bicuspid Aortopathy

Objective

To identify the association between morphological and functional characteristics of the bicuspid aortic valve (BAV) and bicuspid aortopathy and to identify the determinants of aortic dilatation using transthoracic echocardiography (TTE) and cardiac computed tomography (CCT).

Materials and Methods

This study included 312 subjects (mean [SD] age, 52.7 [14.3] years; 227 males [72.8%]) who underwent TTE and CCT. The BAVs were classified by anterior-posterior (BAV-AP) or right-left (BAV-RL) orientation of the cusps and divided according to the presence (raphe+) or absence of a raphe (raphe−) based on the CCT and intraoperative findings. The dimensions of the sinus of Valsalva and the proximal ascending aorta were measured by CCT. We assessed the determinants of aortic root and proximal ascending aortic dilatation (size index > 2.1 cm/m²) by Univariable and multivariable logistic regression analyses.

Results

Of the 312 patients, BAV-AP was present in 188 patients (60.3%), and 185 patients (59.3%) were raphe+. Moderate-to-severe aortic stenosis (AS) was the most common hemodynamic abnormality (54.8%). The most common type of aortopathy was the combined dilated root and mid-ascending aortic phenotype (62.5%). On multivariable analysis, age and AS severity were significantly associated with aortic root dilatation (p < 0.05), and age, sex, and AS severity were significantly associated with ascending aortic dilatation (p < 005). However, the orientation of the cusps, presence of a raphe, and severity of aortic regurgitation were not associated with aortic root and ascending aortic dilatation.

Conclusion

BAV morphological characteristics were not determinants of aortic dilatation. Age, sex, and AS severity were predictors of bicuspid aortopathy. Therefore, age, sex, and AS severity, rather than valve morphology, need to be considered when planning treatment for BAV patients.

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.

The evaluation of annuloplasty in bicuspid aortic valve repair using cardiac magnetic resonance

Background

The incompetent bicuspid aortic valve (BAV) can be replaced or repaired using various surgical techniques. This study sought to assess the efficacy of external annuloplasty and postoperative reverse remodelling using cardiac magnetic resonance (CMR) and compare the results of external and subcommissural annuloplasty.

Methods

Out of a total of 200 BAV repair performed between 2004 and 2018, 21 consecutive patients (median age 54 years) with regurgitation requiring valve repair with annuloplasty without concomitant aortic root surgery were prospectively referred for CMR and transthoracic echocardiography (TTE) one year after the operation. Two aortic annulus stabilization techniques were used: external, circumferential annuloplasty (EA), and subcommissural annuloplasty (SCA).

Results

11 patients received EA and 10 patients were treated using SCA. There was no in-hospital mortality and all patients survived the follow-up period (median: 12.6 months (first quartile: 6.6; third quartile: 14.1). CMR showed strong correlation between postoperative aortic recurrent regurgitant fraction and left ventricular end-diastolic volume (r = 0.62; p = 0.003) as well as left ventricular ejection fraction (r = -0.53; p = 0.01). Patients treated with EA as compared with SCA had larger anatomic aortic valve area measured by CMR (3.5 (2.5; 4.0) vs. 2.5 cm² (2.0; 3.4); p = 0.04). In both EA and SCA group, aortic valve area below 3.5 cm² correlated with no regurgitation recurrency. EA (vs. SCA) was associated with lower peak transvalvular aortic gradients (10 (6; 17) vs. 21 mmHg (15; 27); p = 0.04).

Conclusions

The repair of the bicuspid aortic valve provides significant postoperative reverse remodelling, provided no recurrent regurgitation and durable reduction annuloplasty can be achieved. EA is associated with lower transvalvular gradients and higher aortic valve area assessed by CMR, compared to SCA.

Impact of Regular Physical Activity on Aortic Diameter Progression in Paediatric Patients with Bicuspid Aortic Valve

Patients with bicuspid aortic valve (BAV) have an increased risk of aortic dilation and aortic dissection or rupture. The impact of physical training on the natural course of aortopathy in BAV patients remains unclear. The aim of this study was to evaluate the impact of regular physical activity on aortic diameters in a consecutive cohort of paediatric patients with BAV. Consecutive paediatric BAV patients were evaluated and categorized into two groups: physically active and sedentary subjects. Only the subjects with a complete 2-year follow-up were included in the study. To evaluate the potential impact of physical activity on aortic size, aortic diameters were measured at the sinus of Valsalva and mid-ascending aorta using echocardiography. We defined aortic diameter progression the increase of aortic diameter ≥ 10% from baseline. Among 90 BAV patients (11.5 ± 3.4 years of age, 77% males), 53 (59%) were physically active subjects. Compared to sedentary, physically active subjects were not significantly more likely to have > 10% increase in sinus of Valsalva (13% vs. 8%, p-value = 0.45) or mid-ascending aorta diameter (9% vs. 13%, p-value = 0.55) at 2 years follow-up, both in subjects with sinus of Valsalva diameter progression (3.7 ± 1.0 mm vs. 3.5 ± 0.8 mm, p-value = 0.67) and in those with ascending aorta diameter progression (3.0 ± 0.8 mm vs. 3.2 ± 1.3 mm, p-value = 0.83). In our paediatric cohort of BAV patients, the prevalence and the degree of aortic diameter progression was not significantly different between physically active and sedentary subjects, suggesting that aortic dilation is unrelated to regular physical activity over a 2-year period.

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.

Determinants of aortic growth rate in patients with bicuspid aortic valve by cardiovascular magnetic resonance

Objectives

This study aimed to identify determinants of aortic growth rate in bicuspid aortic valve (BAV) patients. We hypothesised that (1) BAV patients with repaired coarctation (CoA) exhibit decreased aortic growth rate, (2) moderate/severe re-coarctation (reCoA) results in increased growth rate, (3) patients with right non-coronary (RN) valve cusps fusion pattern exhibit increased aortic growth rate compared with right-left cusps fusion and type 0 valves.

Methods

Starting from n=521 BAV patients with cardiovascular magnetic resonance data, we identified n=145 patients with at least two scans for aortic growth analysis. Indexed areas of the sinuses of Valsalva and ascending aorta (AAo) were calculated from cine images in end-systole and end-diastole. Patients were classified based on dilation phenotype, presence of CoA, aortic valve function and BAV morphotype. Comparisons between groups were performed. Linear regression was carried out to identify associations between risk factors and aortic growth rate.

Results

Patients (39±16 years of age, 68% male) had scans 3.7±1.8 years apart; 32 presented with AAo dilation, 18 with aortic root dilation and 32 were overall dilated. Patients with repaired CoA (n=61) showed decreased aortic root growth rate compared with patients without CoA (p≤0.03) regardless of sex or age. ReCoA, aortic stenosis, regurgitation and history of hypertension were not associated with growth rate. RN fusion pattern showed the highest aortic root growth rate and type 0 the smallest (0.30 vs 0.08 cm²/m*year, end-systole, p=0.03).

Conclusions

Presence of CoA and cusp fusion morphotype were associated with changes in rate of root dilation in our BAV population.

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.

Fluid-Structure Interaction Models of Bicuspid Aortic Valves: The Effects of Nonfused Cusp Angles

Bicuspid aortic valve (BAV) is the most common type of congenital heart disease, occurring in 0.5-2% of the population, where the valve has only two rather than the three normal cusps. Valvular pathologies, such as aortic regurgitation and aortic stenosis, are associated with BAVs, thereby increasing the need for a better understanding of BAV kinematics and geometrical characteristics. The aim of this study is to investigate the influence of the nonfused cusp (NFC) angle in BAV type-1 configuration on the valve's structural and hemodynamic performance. Toward that goal, a parametric fluid-structure interaction (FSI) modeling approach of BAVs is presented. Four FSI models were generated with varying NFC angles between 120 deg and 180 deg. The FSI simulations were based on fully coupled structural and fluid dynamic solvers and corresponded to physiologic values, including the anisotropic hyper-elastic behavior of the tissue. The simulated angles led to different mechanical behavior, such as eccentric jet flow direction with a wider opening shape that was found for the smaller NFC angles, while a narrower opening orifice followed by increased jet flow velocity was observed for the larger NFC angles. Smaller NFC angles led to higher concentrated flow shear stress (FSS) on the NFC during peak systole, while higher maximal principal stresses were found in the raphe region during diastole. The proposed biomechanical models could explain the early failure of BAVs with decreased NFC angles, and suggests that a larger NFC angle is preferable in suture annuloplasty BAV repair surgery.

microRNAs in bicuspid aortic valve associated aortopathy: Recent advances and future perspectives

The risk of acute aortic events in patients with bicuspid aortic valve (BAV) constitutes a medical concern in terms of timing and surgical decision. During the past years, there has been a growing interest in the potential of microRNAs (miRNAs) as crucial epigenetic factors in multiple cellular processes associated with BAV aortopathy. Nevertheless, there are still challenges that need to be overcome before miRNAs could enter clinical practice, and further validation studies in larger and well-defined BAV cohorts are now required. This review aims at providing a comprehensive overview of the available data on the expression profiles and function of specific miRNAs in BAV aortopathy, evaluating miRNA signatures as potential molecular markers of disease. We also discuss the role of other novel classes of non-coding RNAs, including long non-coding RNAs and circular RNAs, in BAV-associated aortopathy, mainly regarding their possible implementation as diagnostic and prognostic markers.

An overview of the molecular mechanisms underlying development and progression of bicuspid aortic valve disease

Bicuspid aortic valve (BAV) is a common congenital heart malformation frequently associated with the development of aortic valve diseases and severe aortopathy, such as aortic dilatation, aneurysm and dissection. To date, different genetic loci have been identified in syndromic and non- syndromic forms of BAV. Among these, genes involved in the regulation of extracellular matrix remodelling, epithelial to mesenchymal transition and nitric oxide metabolism appear to be the main contributors to BAV pathogenesis. However, no- single gene model explains BAV inheritance, suggesting that more factors are simultaneously involved. In this regard, characteristic epigenetic and immunological profiles have been documented to contradistinguish BAV individuals. In this review, we provide a comprehensive overview addressing molecular mechanisms involved in BAV development and progression.

Evolving Surgical Approaches to Bicuspid Aortic Valve Associated Aortopathy

Bicuspid aortic valve (BAV) is the most common congenital cardiac pathology which results from the fusion of two adjacent aortic valve cusps. It is associated with dilatation of the aorta, known as bicuspid valve-associated aortopathy or bicuspid aortopathy. Bicuspid aortopathy is progressive and is linked with adverse clinical events. Hence, frequent monitoring and early intervention with prophylactic surgical resection of the proximal aorta is often recommended. Over the past two decades resection strategies and surgical interventions have mainly been directed by surgeon and institution preferences. These practices have ranged from conservative to aggressive approaches based on aortic size and growth criteria. This strategy, however, may not best reflect the risks of important aortic events. A new set of guidelines was proposed for the treatment of bicuspid aortopathy. Herein, we will highlight the most recent findings pertinent to bicuspid aortopathy and its management in the context of a case presentation.

Ascending aortic dilatation rate after transcatheter aortic valve replacement in patients with bicuspid and tricuspid aortic stenosis: A multidetector computed tomography follow-up study

BACKGROUND

Current data is lacking about the progression of ascending aortic dilatation after transcatheter aortic valve replacement (TAVR) in aortic stenosis (AS) patients with bicuspid aortic valve (BAV) and tricuspid aortic valve (TAV). This study aims to assess the ascending aortic dilatation rate (mm/year) after TAVR in patients with BAV versus TAV using a multidetector computed tomography (MDCT) follow-up and to determine the predictors of ascending aortic dilatation rate.

METHODS

Severe AS patients undergoing TAVR from March 2013 to March 2018 at our center with MDCT follow-ups were included. BAV and TAV were identified using baseline MDCT. Baseline and follow-up MDCT images were analyzed, and the diameters of ascending aorta were measured. Study end point is ascending aortic dilatation rate (mm/year). Furthermore, factors predicting ascending aortic dilatation rate were also investigated.

RESULTS

Two hundred and eight patients were included, comprised of 86 BAV and 122 TAV patients. Five, 4, 3, 2, and 1-year MDCT follow-ups were achieved in 7, 9, 30, 46, and 116 patients. The ascending aortic diameter was significantly increased after TAVR in both BAV group (43.7±4.4 mm vs. 44.0±4.5 mm; P<0.001) and TAV group (39.1±4.8 mm vs. 39.7±5.1 mm; P<0.001). However, no difference of ascending aortic dilatation rate was found between BAV and TAV group (0.2±0.8 mm/year vs. 0.3±0.8 mm/year, P=0.592). Multivariate linear regression revealed paravalvular leakage (PVL) grade was independently associated with ascending aortic dilatation rate in the whole population and BAV group, but not TAV group. No aortic events occurred during follow-ups.

CONCLUSION

Ascending aortic size continues to grow after TAVR in BAV patients, but the dilatation rate is mild and comparable to that of TAV patients. PVL grade is associated with ascending aortic dilatation rate in BAV patients post-TAVR.

Clinical and pathophysiological aspects of bicuspid aortic valve disease

A bicuspid aortic valve is not only a common congenital heart defect but also an enigmatic condition that can cause a large spectrum of diseases, such as aortic valve stenosis and severe heart failure in newborns whereas aortic dissection in adults. On the contrary, a bicuspid aortic valve can also occur with normal function throughout life and never need treatment. Numerous genetic mechanisms are involved in the abnormal cellular functions that may cause abnormal development of the aortic valve during early foetal life. As several chromosomal disorders are also associated with a bicuspid valve, there does not appear to be an apparent common trigger to the abnormal development of the aortic valve. The clinical care of the bicuspid aortic valve patient has been changed by a significant body of evidence that has improved the understanding of the natural history of the disease, including when to best intervene with valve replacement and when to provide prophylactic aortic root surgery. Moreover, as bicuspid valve disease is also part of various syndromes, we can identify high-risk patients in whom a bicuspid valve is much more unfavourable than in the normal population. This review provides an overview of all aspects of the bicuspid aortic valve condition and gives an updated perspective on issues from pathophysiology to clinical care of bicuspid aortic valve disease and associated aortic disease in asymptomatic, symptomatic, and pregnant patients, as well as our viewpoint on population screening.

Transcatheter Aortic Valve Replacement for Bicuspid Aortic Valve: Challenges and Pitfalls

Because of the unfavorable anatomic features of bicuspid aortic stenosis (AS), the outcomes of transcatheter aortic valve replacement (TAVR) in bicuspid AS were suboptimal, particularly when using the first-generation transcatheter valves. However, the newer-generation transcatheter valves significantly improved the outcomes of TAVR in bicuspid AS. Nonetheless, long-term durability of transcatheter valves and concomitant aortopathy should be taken into account. Considering the expanding indication of TAVR to lower the surgical risk and a younger population, these issues should be evaluated in future studies.

Predictors of aortic dilation in patients with coarctation of the aorta: evaluation with dual-source computed tomography

Background

Coarctation of aorta (CoA) may progressively develop aortic dilation at other site of the aorta and can lead to fatal aortic diseases. We aimed to evaluate the occurrence of aortic dilation and related predictors in patients with CoA using dual-source computed tomography (DSCT).

Methods

Fifty-three patients with CoA identified by DSCT were retrospectively reviewed. Aortic diameters were measured at six different levels and standardized as z-scores based on the square root of body surface area. Coarctation site–diaphragm ratio (CDR) was used to describe the degree of narrowing. A total of 26 patients were included in mild group (CDR > 50%) and 27 in severe group (CDR < 50%) according to the severity of coarctation. Student’s t-test and Spearman correlation coefficients, univariate and multivariable logistic regression analyses were used to assess the risk factors including age, degree of narrowing and other malformations for aortic dilation.

Results

Severe group had significantly larger z-scores of ascending aorta (2.41 ± 0.39 vs. 2.10 ± 0.57, p < 0.05) and post-coarctation aorta (2.17 ± 0.48 vs. 1.68 ± 0.43, p < 0.001) compared with mild group. Degree of coarctation was associated with the z-scores of the ascending aorta (r = − 0.356, p < 0.05) and post-coarctation aorta (r = − 0.414, p < 0.05). Collateral circulation was related to the z-scores of ascending aorta (r = 0.375, p < 0.05). Increased severity of coarctation was independent predictor of ascending (odds ratio 7.46; 95% CI 1.19–46.76; p < 0.05) and post-coarctation aortic dilation(odds ratio 8.42; 95% CI 1.84–38.56; p < 0.05).

Conclusions

Ascending and post-coarctation aortic diameters or dilations were both associated with the degree of coarctation. By comprehensively evaluating the aortic diameters and associated malformations including collateral circulation, DSCT can aid in stratification of risk for aortic dilation in patients with CoA.

Electronic supplementary material

The online version of this article (10.1186/s12872-018-0863-8) contains supplementary material, which is available to authorized users.

Enlightening the Association between Bicuspid Aortic Valve and Aortopathy

Bicuspid aortic valve (BAV) patients have an increased incidence of developing aortic dilation. Despite its importance, the pathogenesis of aortopathy in BAV is still largely undetermined. Nowadays, intense focus falls both on BAV morphology and progression of valvular dysfunction and on the development of aortic dilation. However, less is known about the relationship between aortic valve morphology and aortic dilation. A better understanding of the molecular pathways involved in the homeostasis of the aortic wall, including the extracellular matrix, the plasticity of the vascular smooth cells, TGFβ signaling, and epigenetic dysregulation, is key to enlighten the mechanisms underpinning BAV-aortopathy development and progression. To date, there are two main theories on this subject, i.e., the genetic and the hemodynamic theory, with an ongoing debate over the pathogenesis of BAV-aortopathy. Furthermore, the lack of early detection biomarkers leads to challenges in the management of patients affected by BAV-aortopathy. Here, we critically review the current knowledge on the driving mechanisms of BAV-aortopathy together with the current clinical management and lack of available biomarkers allowing for early detection and better treatment optimization.

Should the dilated ascending aorta be repaired at the time of bicuspid aortic valve replacement?

OBJECTIVES

Bicuspid aortic valve (BAV) is the most common congenital valvular abnormality and frequently presents with accelerated calcific aortic valve disease, requiring aortic valve replacement (AVR) and thoracic aortic aneurysm and dissection. Supporting evidence for Association Guidelines of aortic dimensions for aortic resection is sparse. We sought to determine whether concurrent repair of dilated or aneurysmal aortic disease during AVR in patients with BAV substantially improves morbidity and mortality outcomes.

METHODS

Mortality and reoperation outcomes of 1301 adults with BAV and dilated aorta undergoing AVR-only surgery were compared to patients undergoing AVR with aortic resection (AVR-AR) using Cox proportional hazards modelling and patient matching.

RESULTS

Clinically important differences in patient characteristics, aortic valve function and aortic dimensions were identified between cohorts. Event rates were low, with rates of reoperation and death within 1 year of only 1.8% and 5.4%, respectively, and no aortic dissection observed during follow-up. There were no significant differences in reoperation or mortality outcomes between the AVR-only and AVR-AR cohorts. Age, aortic dimension or a combination thereof was not associated with better or worse outcomes after each AVR-AR compared with AVR.

CONCLUSIONS

We conclude AVR-only and AVR-AR surgery have low morbidity and mortality and have utility over a wide range of age and aortic sizes. Our results do not provide support for the 45-mm aortic dimension recommended in the current guidelines for aortic resection while performing AVR or any other specific dimension.

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.

Aortic Cross-Sectional Area/Height Ratio and Outcomes in Patients With Bicuspid Aortic Valve and a Dilated Ascending Aorta

Background—

In patients with bicuspid aortic valve and dilated proximal ascending aorta, we sought to assess (1) factors associated with increased longer-term cardiovascular mortality and (2) incremental prognostic use of indexing aortic root to patient height.

Methods and Results—

We studied 969 consecutive bicuspid aortic valve patients (50±13 years; 87% men) with proximal aorta ≥4 cm, who also had a gated contrast-enhanced thoracic computed tomography or magnetic resonance angiography. A ratio of ascending aortic area/height was calculated on tomography, and ≥10 cm 2 /m was considered abnormal, as previously reported. Society of Thoracic Surgeons score and cardiovascular death were recorded. Greater than or equal to III+ aortic regurgitation and severe aortic stenosis were seen in 37% and 10%, respectively. Society of Thoracic Surgeons score and right ventricular systolic pressure were 2±3 and 15±16 mm Hg, respectively. Abnormal ascending aortic area/height ratio was noted in 33%; 44% underwent ascending aortic surgery at 34 days. At 10.8 years (interquartile range, 9.6–12.3), 82 (9%) died (0.4% in-hospital postoperative mortality). On multivariable Cox survival analysis, ascending aortic area/height ratio (hazard ratio, 2; 95% confidence interval, 1.20–3.35) was associated with cardiovascular death, whereas aortic surgery (hazard ratio, 0.46; confidence interval, 0.26–0.80) was associated with improved survival (both P <0.01). Of the 405 patients with ascending aortic diameter of 4.5 to 5.5 cm, 64% had an abnormal ascending aortic area/height ratio, and 70% deaths occurred in patients with an abnormal ratio.

Conclusions—

In bicuspid aortic valve patients with dilated proximal ascending aorta, ascending aortic area/height ratio was independently associated with cardiovascular death.

Bicuspid aortic valve syndrome: a multidisciplinary approach for a complex entity

Bicuspid aortic valve (BAV) or bicuspid aortopathy is the most common congenital heart disease. It can be clinically silent and it is often identified as an incidental finding in otherwise healthy, asymptomatic patients. However, it can be dysfunctioning at birth, even requiring neonatal intervention, or, in time, lead to aortic stenosis, aortic insufficiency, and endocarditis, and also be associated with aortic aneurysm and aortic dissection. Given its prevalence and significant complications, it is estimated that BAV is responsible for more deaths and morbidity than the combined effects of all the other congenital heart defects. Pathology of BAV is still not well known and many questions are unresolved. In this manuscript we review some aspects on bicuspid aortopathy, a heterogeneous and frequent disease in which like some authors have previously described, complex gene environment are present. Further investigations and, what is more, multidisciplinary teams are needed to improve our knowledge on this really fascinating disease.

Bicuspid aortic valve outcomes

BACKGROUND

Bicuspid aortic valve is the most common CHD. Its association with early valvular dysfunction, endocarditis, thoracic aorta dilatation, and aortic dissection is well established.

OBJECTIVE

The aim of this study was to assess the incidence and predictors of cardiac events in adults with bicuspid aortic valve.

METHODS

We carried out a retrospective analysis of cardiac outcomes in ambulatory adults with bicuspid aortic valve followed-up in a tertiary hospital centre. Outcomes were defined as follows: interventional - intervention on the aortic valve or thoracic aorta; medical - death, aortic dissection, aortic valve endocarditis, congestive heart failure, arrhythmias, or ischaemic heart disease requiring hospital admission; and a composite end point of both. Kaplan-Meier curves were generated to determine event rates, and predictors of cardiac events were determined by multivariate analysis.

RESULTS

A total of 227 patients were followed-up over 13±9 years; 29% of patients developed severe aortic valve dysfunction and 12.3% reached ascending thoracic aorta dimensions above 45 mm. At least one cardiac outcome occurred in 38.8% of patients, with an incidence rate at 20 years of follow-up of 47±4%; 33% of patients were submitted to an aortic valve or thoracic aorta intervention. Survival 20 years after diagnosis was 94±2%. Independent predictors of the composite end point were baseline moderate-severe aortic valve dysfunction (hazard ratio, 3.19; 95% confidence interval, 1.35-7.54; p<0.01) and aortic valve leaflets calcification (hazard ratio, 4.72; 95% confidence interval, 1.91-11.64; p<0.005).

CONCLUSIONS

In this study of bicuspid aortic valve, the long-term survival was excellent but with occurrence of frequent cardiovascular events. Baseline aortic valve calcification and dysfunction were the only independent predictors of events.

Clinical and echocardiographic predictors of long-term outcome of a large cohort of patients with bicuspid aortic valve

BACKGROUND AND OBJECTIVES

Bicuspid aortic valve (BAV) disease is the most common congenital cardiac malformation. The aim of the present article is to determine clinical and echocardiographic prognostic factors and provide a predictive model of outcome of a large cohort of patients with BAV.

METHODS

We retrospectively enrolled 337 patients consecutively assessed for echocardiography at our Cardiology Department from 1993 to 2014. We considered aortic valve replacement, aortic surgery and cardiovascular death as a clinical combined end-point. Predictors of outcome were determined by Cox regression.

RESULTS

Mean age was 29.2 ± 19.8 years, median 27.1 years. A total of 38.4% patients presented a history of hypertension. Mean duration of follow-up was 8.4 ± 6.1 years, range 0-21 years. A total of 73 patients underwent aortic valve replacement and/or aortic surgery during follow-up. Age at surgery was 45.2 ± 15.6 years. Seven patients died because of cardiovascular causes. At multivariate analysis, baseline clinical predictors were history of hypertension [hazard ratio (HR) 2.289, 95% confidence interval (CI) 1.350-3.881, P = 0.002], larger ascending aortic diameter (HR 2.537, 95% CI 1.888-3.410, P < 0.001), moderate-to-severe aortic regurgitation (HR 2.266, 95% CI 1.402-3.661, P = 0.001) and moderate-to-severe aortic stenosis (HR 2.807, 95% CI 1.476-5.338, P = 0.002). A predictive model was created by integrating these four independent covariates. It allows the calculation of calculate a risk score for each patient, which helps better tailor appropriate treatment in BAV patients.

CONCLUSION

At enrolment, history of hypertension, a wider aortic diameter, moderate-to-severe aortic regurgitation and aortic stenosis were independently correlated to combined end-point. Long-term follow-up showed low cardiovascular mortality (2.1%) and a high prevalence of cardiac surgery (21.6%).

Clinical and echocardiographic determinants in bicuspid aortic dilatation: Results from a longitudinal observational study

Bicuspid aortic valve (BAV) disease is associated with aortic dilatation. Timing of follow-up and surgery is challenging. Hence, there is an unmet clinical need for additional risk stratification. It is unclear whether valve morphology is associated with dilatation rates. Therefore, the objective of this study was to examine the association between clinical and echocardiographic determinants (including valve morphology) and aortic dimension and the progression rate of dilatation.Aortic dimensions were assessed on serial echocardiographic images between 1999 and 2014 in a population of 392 patients with BAVs in a tertiary care center in the Netherlands. Analyses using mixed linear models were performed.Mean age of participants was 48 ± 17 years and 69% were male. BAV morphology was associated with aortic dimensions, as well as age, sex, BSA, and valvular dysfunction. Tubular ascending aorta, sinus of Valsalva, and sinotubular junction showed a dilatation rate of 0.32, 0.18, and 0.06 mm/year, respectively. Dilatation rate was not associated with valve morphology.In the present study, there is no association between BAV morphology and aortic dilatation rates. Therefore, morphology is of limited use in prediction of aortic growth. Discovering fast progressors remains challenging.

Association between bicuspid aortic valve morphotype and regional dilatation of the aortic root and trunk

Thoracic aortic disease, including thoracic aortic aneurysm (TAA), is frequently seen in patients with bicuspid aortic valve (BAV). We hypothesized that BAV morphotype would be associated with aortic aneurysm phenotypes but that other patient variables would significantly modify this relationship. 829 patients between 18 and 90 years with BAV and available raw imaging of the aortic valve and the ascending aorta to its mid-portion prior to aortic valve and aortic surgery were examined. The sinuses of Valsalva and proximal ascending aorta were measured from 2-dimensional co-planar echocardiographic images. We observed strong associations between patient habitus and raw and normalized dimensions of the aortic root and ascending aorta. Patients with R-L morphotype presented at an older age with larger aortic root but similar ascending aortic dimensions. After accounting for patient morphometric characteristics and severity of aortic valve disease, patients with R-L valve morphotype were marginally more likely to have an aortic root aneurysm (86% vs. 78%; P = 0.043), defined as aortic root dimension Z score ≥3. We observed only small differences in aortic dimensions between BAV morphotypes, that are eclipsed by variation in patient habitus. We interpret these findings to mean that BAV patients will not likely benefit from therapies based on aortic valve morphotype. Rather, we propose that all BAV patients should undergo longitudinal follow-up, independent of valve morphotype. Guidelines for aortic surgery based upon dimensions alone may be improved by considering patient characteristics such as age, body size and other characteristics.

Dilatation of the initially non-aneurysmal ascending aorta after replacement of a bicuspid versus tricuspid aortic valve

Objective

To compare the aortic diameter after isolated aortic valve replacement (AVR) in patients with a bicuspid (BAV) or tricuspid aortic valve (TAV) and an initially normal ascending aorta.

Methods

Patients with an ascending aortic diameter of < 45 mm who had undergone isolated AVR were studied. Ultrasonic cardiographic measurements of the ascending aortic diameter made pre- and postoperatively and follow-up data concerning adverse aortic events and death were analyzed.

Results

A total of 613 patients were included in this retrospective study; of these, 211 had a BAV and 402 had a TAV. In both groups, the ascending aorta significantly expanded but was non-aneurysmal during follow-up; however, the difference between the two groups was not significant. Cox regression analysis showed no significant effect associated with the presence of a BAV on adverse aortic events or death.

Conclusion

Dilatation of the ascending aorta was observed after AVR in both groups, but was not more pronounced in patients with a BAV. Long-term follow-up for ascending aortic aneurysm is necessary after AVR in both patients with a BAV and those with a TAV.

Bicuspid Aortic Valve: Unlocking the Morphogenetic Puzzle

Although bicuspid aortic valve is the most common congenital abnormality, it is perhaps erroneous to consider this disease one clinical entity. Rather, it may be useful to consider it a cluster of diseases incorporating different phenotypes, etiologies, and pathogenesis. Discussion of bicuspid aortic valve can be difficult because there is no clear consensus on a phenotypic description among authors, and many classification schemes have been proposed. The literature suggests that different phenotypes have different associations and clinical manifestations. In addition, recent studies suggest a genetic basis for the disease, yet few genes have so far been described. Furthermore, recent scientific literature has been focusing on the increased risk of aortic aneurysms, but the pathogenesis of bicuspid aortic valve aortopathy is still unclear. The aim of this paper is to review the current evidence about the unsolved issues around bicuspid aortic valve.