Changes in aorta hemodynamics in Left-Right Type 1 bicuspid aortic valve patients after replacement with bioprosthetic valves: An in-silico study

Bicuspid aortic valve (BAV) is the most common cardiac congenital abnormality with a high rate of concomitant aortic valve and ascending aorta (AAo) pathologic changes throughout the patient's lifetime. The etiology of BAV-related aortopathy was historically believed to be genetic. However, recent studies theorize that adverse hemodynamics secondary to BAVs also contribute to aortopathy, but their precise role, specifically, that of wall shear stress (WSS) magnitude and directionality remains controversial. Moreover, the primary therapeutic option for BAV patients is aortic valve replacement (AVR), but the role of improved post-AVR hemodynamics on aortopathy progression is also not well-understood. To address these issues, this study employs a computational fluid dynamics model to simulate personalized AAo hemodynamics before and after TAVR for a small cohort of 6 Left-Right fused BAV patients. Regional distributions of five hemodynamic metrics, namely, time-averaged wall shear stress (TAWSS) and oscillating shear index (OSI), divergence of wall shear (DWSS), helicity flux integral & endothelial cell activation potential (ECAP), which are hypothesized to be associated with potential aortic injury are computed in the root, proximal and distal ascending aorta. BAVs are characterized by strong, eccentric jets, with peak velocities exceeding 4 m/s and axially circulating flow away from the jets. Such conditions result in focused WSS loading along jet attachment regions on the lumen boundary and weaker, oscillating WSS on other regions. The jet attachment regions also show alternating streaks of positive and negative DWSS, which may increase risk for local tissue stretching. Large WSS magnitudes, strong helical flows and circumferential WSS have been previously implicated in the progression of BAV aortopathy. Post-intervention hemodynamics exhibit weaker, less eccentric jets. Significant reductions are observed in flow helicity, TAWSS and DWSS in localized regions of the proximal AAo. On the other hand, OSI increases post-intervention and ECAP is observed to be low in both pre- and post-intervention scenarios, although significant increases are also observed in this ECAP. These results indicate a significant alleviation of pathological hemodynamics post AVR.

Filamin A heart valve disease as a genetic cause of inherited bicuspid and tricuspid aortic valve disease

OBJECTIVE

Variants in the FLNA gene have been associated with mitral valve dystrophy (MVD), and even polyvalvular disease has been reported. This study aimed to analyse the aortic valve and root involvement in FLNA-MVD families and its impact on outcomes.

METHODS

262 subjects (37 (18-53) years, 140 male, 79 carriers: FLNA+) from 4 FLNA-MVD families were included. Echocardiography was performed in 185 patients and histological analysis in 3 explanted aortic valves. The outcomes were defined as aortic valve surgery or all-cause mortality.

RESULTS

Aortic valve alterations were found in 58% of FLNA+ compared with 6% of FLNA- (p<0.001). 9 (13.4%) FLNA+ had bicuspid aortic valve compared with 4 (3.4%) FLNA- (p=0.03). Overall, the transvalvular mean gradient was slightly increased in FLNA+ (4.8 (4.1-6.1) vs 4.0 (2.9-4.9) mm Hg, p=0.02). The sinuses of Valsalva and sinotubular junction diameters were enlarged in FLNA+ subjects (all p<0.05). 8 FLNA+ patients underwent aortic valve surgery (0 in relatives; p<0.001). Myxomatous remodelling with an infiltration of immune cells was observed. Overall survival was similar between FLNA+ versus FLNA- subjects (86±5% vs 85±6%, p=0.36). There was no statistical evidence for an interaction between genetic status and sex (p=0.15), but the survival tended to be impaired in FLNA+ men (p=0.06) whereas not in women (p=0.71).

CONCLUSION

The patients with FLNA variants present frequent aortic valve disease and worse outcomes. Bicuspid aortic valve is more frequent in patients carrying the FLNA-MVD variants. These unique features should be factored into the management of patients with dystrophic and/or bicuspid aortic valve.

Swiss Cheese Heart: A Tale of Multiple Valve Perforations

Gerbode defect, an anomalous connection between the left ventricle and right atrium, is often congenital but can be acquired or iatrogenically formed. We present an exceedingly rare case of this defect associated with multiple valve perforation in an otherwise healthy patient with bicuspid aortic valve and endocarditis.

Patient-specific analysis of bicuspid aortic valve hemodynamics using a fully coupled fluid-structure interaction model

Bicuspid aortic valve (BAV), the most common congenital heart disease, is prone to develop significant valvular dysfunction and aortic wall abnormalities such as ascending aortic aneurysm. Growing evidence has suggested that abnormal BAV hemodynamics could contribute to disease progression. In order to investigate BAV hemodynamics, we performed 3D patient-specific fluid-structure interaction (FSI) simulations with fully coupled blood flow dynamics and valve motion throughout the cardiac cycle. Results showed that the hemodynamics during systole can be characterized by a systolic jet and two counter-rotating recirculation vortices. At peak systole, the jet was usually eccentric, with asymmetric recirculation vortices and helical flow motion in the ascending aorta. The flow structure at peak systole was quantified using the vorticity, flow rate reversal ratio and local normalized helicity (LNH) at four locations from the aortic root to the ascending aorta. The systolic jet was evaluated with the peak velocity, normalized flow displacement, and jet angle. It was found that peak velocity and normalized flow displacement (rather than jet angle) gave a strong correlation with the vorticity and LNH in the ascending aorta, which suggests that these two metrics could be used for clinical noninvasive evaluation of abnormal blood flow patterns in BAV patients.

Coarctation of Aorta With Tricuspid Aortic Valve Is Not Associated With Ascending Aortic Aneurysm

BACKGROUND

Aortic aneurysm is common in patients with coarctation of aorta (COA), but it is unclear whether the risk of aortic aneurysms is due to COA or related to the presence of other risk factors such as bicuspid aortic valve (BAV) and hypertension.

OBJECTIVES

The purpose of this study was to assess the relationship among COA, BAV, and thoracic aortic aneurysms.

METHODS

A total of 867 patients with COA (COA group) were matched 1:1:1 to 867 patients with isolated BAV (BAV group) and 867 patients without structural heart disease (SHD) (no-SHD group). The COA group was further subdivided into a COA+BAV subgroup (n = 304 [35%]), and COA with tricuspid aortic valve (TAV) (COA+TAV subgroup [n = 563 (65%)]). Aortic dimensions were assessed at baseline and at 3, 5, and 7 years.

RESULTS

Compared with the no-SHD group, the COA+BAV subgroup had larger aortic root diameter (37 mm [Q1-Q3: 30-43 mm] vs 32 mm [Q1-Q3: 27-35 mm]; P < 0.001) and mid ascending aorta dimeter (34 mm [Q1-Q3: 29-40 mm] vs 28 mm [Q1-Q3: 24-31 mm]; P = 0.008). Similarly, the BAV group had larger aortic root diameter (37 mm [Q1-Q3: 30-42 mm] vs 32 mm [Q1-Q3: 27-35 mm]; P < 0.001), and mid ascending aorta dimeter (35 mm [Q1-Q3: 30-40 mm] vs 28 mm [Q1-Q3: 24-31 mm]; P < 0.001). Compared with the COA+TAV subgroup, the COA+BAV subgroup and BAV group were associated with larger aortic root and mid ascending aorta diameter at baseline and follow-up. The risk of acute aortic complications was low in all groups.

CONCLUSIONS

These findings suggest that BAV (and not COA) was associated with ascending thoracic aorta dimensions, and that patients with COA+TAV were not at a greater risk of developing ascending aortic aneurysms as compared with patients without SHD.

Computed tomography calcium scoring in aortic stenosis: bicuspid versus tricuspid morphology

OBJECTIVE

CT aortic valve calcium score (AVCscore) and density (AVCdensity) thresholds have been recommended for aortic stenosis (AS) severity assessment in tricuspid aortic valve (TAV). We aimed to compare AVCscore and AVCdensity in bicuspid aortic valve (BAV) versus TAV.

METHODS

Retrospective single-centre study of patients with echocardiographic AS-severity and CT-AVC assessments within 6 months, and left ventricular ejection fraction ≥50%, all referred for clinical AS evaluation.Severe AS was defined as aortic valve area (AVA) ≤1 cm2 or indexed AVA ≤0.6cm2/m2 plus mean gradient ≥40 mm Hg or peak velocity ≥4 m/s. AVC was assessed by Agatston method.

RESULTS

Of the 1957 patients, 328 had BAV and 1629 had TAV, age 65±11 vs 80±9 years (p<0.001), men 65% vs 56% (p=0.006), respectively. BAV morphology was associated with higher AVCscore and AVCdensity independent of age, comorbidities and AS severity (p<0.001) in men only (sex and BAV interaction p<0.001). In patients with severe AS, mean AVCscore and AVCdensity were higher in BAV-men than that in TAV-men (both p<0.001), but similar in BAV-women and TAV-women (both p≥0.4). Such patterns remained the same after adjustment for clinical covariates and AS severity. Best thresholds for severe AS diagnosis in BAV-men were 2916 AU by AVCscore and 600 AU/cm2 by AVCdensity which were higher than the guideline-recommended thresholds, while thresholds in BAV-women (1036 AU and 282 AU/cm2) were similar to guideline-recommended ones.

CONCLUSION

Valve calcification in AS differs according to valve morphology and sex. BAV-men with severe AS exhibit greater AVCscore and AVCdensity than TAV-men. This presents a diagnostic challenge to the current guidelines, which needs confirmation in larger studies.

Predictive machine learning models for ascending aortic dilatation in patients with bicuspid and tricuspid aortic valves undergoing cardiothoracic surgery: a prospective, single-centre and observational study

OBJECTIVES

The objective of this study was to develop clinical classifiers aiming to identify prevalent ascending aortic dilatation in patients with bicuspid aortic valve (BAV) and tricuspid aortic valve (TAV).

DESIGN AND SETTING

A prospective, single-centre and observational cohort.

PARTICIPANTS

The study involved 543 BAV and 491 TAV patients with aortic valve disease and/or ascending aortic dilatation, excluding those with coronary artery disease, undergoing cardiothoracic surgery at the Karolinska University Hospital (Sweden).

MAIN OUTCOME MEASURES

Predictors of high risk of ascending aortic dilatation (defined as ascending aorta with a diameter above 40 mm) were identified through the application of machine learning algorithms and classic logistic regression models.

EXPOSURES

Comprehensive multidimensional data, including valve morphology, clinical information, family history of cardiovascular diseases, prevalent diseases, demographic details, lifestyle factors, and medication.

RESULTS

BAV patients, with an average age of 60.4±12.4 years, showed a higher frequency of aortic dilatation (45.3%) compared with TAV patients, who had an average age of 70.4±9.1 years (28.9% dilatation, p <0.001). Aneurysm prediction models for TAV patients exhibited mean area under the receiver-operating-characteristic curve (AUC) values above 0.8, with the absence of aortic stenosis being the primary predictor, followed by diabetes and high-sensitivity C reactive protein. Conversely, prediction models for BAV patients resulted in AUC values between 0.5 and 0.55, indicating low usefulness for predicting aortic dilatation. Classification results remained consistent across all machine learning algorithms and classic logistic regression models.

CONCLUSION AND RECOMMENDATION

Cardiovascular risk profiles appear to be more predictive of aortopathy in TAV patients than in patients with BAV. This adds evidence to the fact that BAV-associated and TAV-associated aortopathy involves different pathways to aneurysm formation and highlights the need for specific aneurysm preventions in these patients. Further, our results highlight that machine learning approaches do not outperform classical prediction methods in addressing complex interactions and non-linear relations between variables.

Later aorta operation after aortic valve replacement for bicuspid aortic valve

BACKGROUND

We investigated long-term outcomes, particularly later aorta operations and overall death in patients who underwent aortic valve replacement for bicuspid aortic valve without aortic surgery.

METHODS

Between January 2002 and December 2022, 274 patients underwent aortic valve replacement for bicuspid aortic valve at our institution. Of them, 181 patients who did not undergo aortic surgery, in accordance with current guidelines, were analyzed retrospectively.

RESULTS

The median follow-up duration was 6.1 (2.0-10.6) years, and follow-up was completed in 97.8% of pateints. There were 3 patients (1.7%) who underwent later aorta operation during follow-up period. The cumulative later aorta operation rate at 10 years adjusting overall death as competing risk was 16.3%, and the estimated rates of freedom from overall death at 10 years was 83.7%. Fine-Gray competing risk regression model showed that aortic valve stenosis was only the predictor of later aorta operation (hazard ratio 8.477; p = 0.012). In multivariable Cox models, predictors of overall death were aortic valve stenosis (hazard ratio: 8.270, 95% confidence interval: 1.082-63.235; p = 0.042) and operation time (hazard ratio: 1.011, 95% confidence interval: 1.004-1.017; p = 0.002).

CONCLUSIONS

Patients with bicuspid aortic valve with ascending aortic diameter less than 45 mm are at low risk of later aorta operation after isolated aortic valve replacement.

Prognostic Implications of Left Atrial Strain in Bicuspid Aortic Valve With Chronic Aortic Regurgitation

BACKGROUND

Left atrial reservoir strain (LARS) is a novel imaging biomarker of left ventricular diastolic dysfunction. This study aimed to examine the prognostic implications of LARS in patients with bicuspid aortic valve and significant (moderate-severe to severe) aortic regurgitation.

METHODS AND RESULTS

A total of 220 patients with bicuspid aortic valve and significant aortic regurgitation were prospectively enrolled in our study. LARS and left ventricular global longitudinal strain were derived from speckle-tracking echocardiography. The end point was a composite of all-cause mortality, heart failure hospitalization, and aortic valve repair or replacement. The threshold value of LARS <24% was used to identify impaired left atrial mechanics based on prior results. During a median follow-up of 364 (interquartile range, 294-752) days, 46 patients (20.9%) reached the composite end points. On multivariable Cox analysis, impaired LARS (adjusted hazard ratio, 2.08 [95% CI, 1.05-4.11]; P=0.036) was a statistically significant predictor of composite end points after adjustment for other statistically significant predictors. Finally, adding impaired LARS to other statistically significant predictors (New York Heart Association functional class and left ventricular global longitudinal strain) significantly improved the global χ2 (from 32.19 to 36.56; P=0.037) and reclassification (continuous net reclassification index=0.55; P<0.001) of the prediction model.

CONCLUSIONS

In patients with bicuspid aortic valve and significant aortic regurgitation, the impairment of LARS is a strong independent prognostic predictor and confers incremental prognostic utility over clinical and other echocardiographic parameters. These findings suggest that LARS could be considered in risk stratification for such populations.

Oscillatory shear stress is elevated in patients with bicuspid aortic valve and aortic regurgitation: a 4D flow cardiovascular magnetic resonance cross-sectional study

AIMS

Patients with bicuspid aortic valve (BAV) and aortic regurgitation have higher rate of aortic complications compared with patients with BAV and stenosis, as well as BAV without valvular disease. Aortic regurgitation alters blood haemodynamics not only in systole but also during diastole. We therefore sought to investigate wall shear stress (WSS) during the whole cardiac cycle in BAV with aortic regurgitation.

METHODS AND RESULTS

Fifty-seven subjects that underwent 4D flow cardiovascular magnetic resonance imaging were included: 13 patients with BAVs without valve disease, 14 BAVs with aortic regurgitation, 15 BAVs with aortic stenosis, and 22 normal controls with tricuspid aortic valve. Peak and time averaged WSS in systole and diastole and the oscillatory shear index (OSI) in the ascending aorta were computed. Student's t-tests were used to compare values between the four groups where the data were normally distributed, and the non-parametric Wilcoxon rank sum tests were used otherwise. BAVs with regurgitation had similar peak and time averaged WSS compared with the patients with BAV without valve disease and with stenosis, and no regions of elevated WSS were found. BAV with aortic regurgitation had twice as high OSI as the other groups (P ≤ 0.001), and mainly in the outer mid-to-distal ascending aorta.

CONCLUSION

OSI uniquely characterizes altered WSS patterns in BAVs with aortic regurgitation, and thus could be a haemodynamic marker specific for this specific group that is at higher risk of aortic complications. Future longitudinal studies are needed to verify this hypothesis.

Extracellular Matrix Disorganization Caused by ADAMTS16 Deficiency Leads to Bicuspid Aortic Valve With Raphe Formation

BACKGROUND

A better understanding of the molecular mechanism of aortic valve development and bicuspid aortic valve (BAV) formation would significantly improve and optimize the therapeutic strategy for BAV treatment. Over the past decade, the genes involved in aortic valve development and BAV formation have been increasingly recognized. On the other hand, ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) gene family members have been reported to be able to modulate cardiovascular development and diseases. The present study aimed to further investigate the roles of ADAMTS family members in aortic valve development and BAV formation.

METHODS

Morpholino-based ADAMTS family gene-targeted screening for zebrafish heart outflow tract phenotypes combined with DNA sequencing in a 304 cohort BAV patient registry study was initially carried out to identify potentially related genes. Both ADAMTS gene-specific fluorescence in situ hybridization assay and genetic tracing experiments were performed to evaluate the expression pattern in the aortic valve. Accordingly, related genetic mouse models (both knockout and knockin) were generated using the CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/clustered regularly interspaced short palindromic repeat-associated 9) method to further study the roles of ADAMTS family genes. The lineage-tracing technique was used again to evaluate how the cellular activity of specific progenitor cells was regulated by ADAMTS genes. Bulk RNA sequencing was used to investigate the signaling pathways involved. Inducible pluripotent stem cells derived from both BAV patients and genetic mouse tissue were used to study the molecular mechanism of ADAMTS. Immunohistochemistry was performed to examine the phenotype of cardiac valve anomalies, especially in the extracellular matrix components.

RESULTS

ADAMTS genes targeting and phenotype screening in zebrafish and targeted DNA sequencing on a cohort of patients with BAV identified ADAMTS16 (a disintegrin and metalloproteinase with thrombospondin motifs 16) as a BAV-causing gene and found the ADAMTS16 p. H357Q variant in an inherited BAV family. Both in situ hybridization and genetic tracing studies described a unique spatiotemporal pattern of ADAMTS16 expression during aortic valve development. Adamts16+/- and Adamts16+/H355Q mouse models both exhibited a right coronary cusp-noncoronary cusp fusion-type BAV phenotype, with progressive aortic valve thickening associated with raphe formation (fusion of the commissure). Further, ADAMTS16 deficiency in Tie2 lineage cells recapitulated the BAV phenotype. This was confirmed in lineage-tracing mouse models in which Adamts16 deficiency affected endothelial and second heart field cells, not the neural crest cells. Accordingly, the changes were mainly detected in the noncoronary and right coronary leaflets. Bulk RNA sequencing using inducible pluripotent stem cells-derived endothelial cells and genetic mouse embryonic heart tissue unveiled enhanced FAK (focal adhesion kinase) signaling, which was accompanied by elevated fibronectin levels. Both in vitro inducible pluripotent stem cells-derived endothelial cells culture and ex vivo embryonic outflow tract explant studies validated the altered FAK signaling.

CONCLUSIONS

Our present study identified a novel BAV-causing ADAMTS16 p. H357Q variant. ADAMTS16 deficiency led to BAV formation.

Associations of Lifelong Exercise Characteristics With Valvular Function and Aortic Diameters in Patients With a Bicuspid Aortic Valve

BACKGROUND

The potential impact of exercise on valvular function and aortic diameters in patients with a bicuspid aortic valve remains unclear. Therefore, we assessed the association between lifelong exercise characteristics, valvular dysfunction, and aortic dilatation in patients with a bicuspid aortic valve.

METHODS AND RESULTS

In this cross-sectional study, exercise volume (metabolic equivalent of task minutes per week), exercise intensity, and sport type were determined from the age of 12 years to participation using a validated questionnaire. Echocardiography was used to assess aortic stenosis or aortic regurgitation and to measure diameters at the sinuses of Valsalva and ascending aorta. Aortic dilatation was defined as a Z-score ≥2. Four hundred and seven patients (42±17 years, 60% men) were included, of which 133 were sedentary (<500 metabolic equivalent of task minutes per week), 94 active (500-1000 metabolic equivalent of task minutes per week), and 180 highly active (≥1000 metabolic equivalent of task minutes per week). Moderate-to-severe aortic stenosis or aortic regurgitation was present in 23.7% and 20.0%, respectively. Sinuses of Valsalva and ascending aorta diameters were 34.8±6.6 and 36.5±8.1 mm, whereas aortic dilatation was found in 21.6% and 53.4%, respectively. Exercise volume was not associated with valve dysfunction or aortic dilatation. Vigorous intensity and mixed sports were associated with a lower prevalence of aortic stenosis (adjusted odds ratios, 0.43 [0.20-0.94] and adjusted odds ratios, 0.47 [0.23-0.95]). Exercise intensity and sport type were not associated with aortic regurgitation and aortic dilatation.

CONCLUSIONS

We found no deleterious associations between lifelong exercise characteristics, valvular dysfunction, and aortic dilatation in patients with a bicuspid aortic valve. Vigorous intensity and exercise in mixed sports were associated with a lower prevalence of moderate-to-severe aortic stenosis. These observations suggest that lifelong exercise does not appear to induce adverse cardiovascular effects in patients with a bicuspid aortic valve.

Well-functioning bicuspid aortic valves should be preserved during aortic replacement for the ascending aortopathy phenotype

OBJECTIVES

Consensus has not been reached on whether or not to replace or preserve a well-functioning bicuspid aortic valve (BAV) in patients undergoing aortic replacement for the ascending phenotype of BAV aortopathy. We characterize morphology, evaluate progression of aortic regurgitation or aortic stenosis, and investigate the need for aortic valve replacement in patients whose well-functioning BAV was preserved during ascending aortic replacement ≥10 years prior.

METHODS

From January 1991 to August 2011, 191 patients with a well-functioning BAV underwent supracoronary aortic replacement (113 valves were minimally repaired). Aortic morphology was evaluated, aortic regurgitation grade and transvalvular aortic gradient modeled parametrically, and survival assessed by the Kaplan-Meier method. Median follow-up was 10 years.

RESULTS

Mean aortic diameter was 2.9 ± 0.53 cm at the annulus and 4.2 ± 0.55 cm at the sinuses. Mean maximum ascending diameter was 5.1 ± 0.49 cm. All patients exhibited a cusp-fusion BAV phenotype. Fifteen-year progression to severe aortic regurgitation was 3.2%. Mean aortic valve gradient began to rise 5 years postoperatively to 27 mm Hg by 14 years. Freedom from aortic valve replacement at 1, 5, 10, and 15 years was 100%, 95%, 83%, and 63%, respectively. Minimal valve repair was not associated with late aortic valve replacement. Fifteen-year survival was 74%.

CONCLUSIONS

Preserving a well-functioning BAV should be considered in carefully selected patients undergoing aortic replacement for the ascending phenotype of BAV aortopathy. The valves remain durable in the long term, with slow progression of regurgitation or stenosis, and low probability of aortic valve replacement through 10 years.

Use of transillumination echocardiography in the assessment and diagnosis of bicuspid aortic valve

Bicuspid aortic valve is the most common congenital heart defect. Transthoracic echocardiogram is the initial tool to assess and diagnose this condition, however, transesophageal echocardiogram with 3D modalities, including transillumination have a better anatomical and functional evaluation of the valve, allowing to classify the bicuspid aortic valve according to the position of the raphe and assess the main vessels for complications or exclude other cardiovascular diseases.

Combination of an extremely rare and a common congenital valvular anomalies: Accessory mitral valve chordae from left atrium and bicuspid aortic valve

Accessory chordae tendineae is an extremely rare anomaly. In this case report, we described a 61-year-old female patient newly diagnosed with the combination of an accessory mitral valve chordae extending from left atrium which is an extremely rare congenital anomaly and a bicuspid aortic valve. In our patient, three-dimensional echocardiography showed incremental value over two-dimensional echocardiography in the assessment of the exact localization and the extend of accessory chordea.

Aortic area/height ratio, peak wall stresses, and outcomes in veterans with tricuspid versus bicuspid aortic valve-associated ascending thoracic aortic aneurysms

BACKGROUND

In ascending thoracic aortic aneurysm risk stratification, aortic area/height ratio is a reasonable alternative to maximum diameter. Biomechanically, aortic dissection may be initiated by wall stress exceeding wall strength. Our objective was to evaluate the association between aortic area/height and peak aneurysm wall stresses in relation to valve morphology and 3-year all-cause mortality.

METHODS

Finite element analysis was performed on 270 ascending thoracic aortic aneurysms (46 associated with bicuspid and 224 with tricuspid aortic valves) in veterans. Three-dimensional aneurysm geometries were reconstructed from computed tomography and models developed accounting for prestress geometries. Fiber-embedded hyperelastic material model was applied to obtain aneurysm wall stresses during systole. Correlations of aortic area/height ratio and peak wall stresses were compared across valve types. Area/height ratio was evaluated across peak wall stress thresholds obtained from proportional hazards models of 3-year all-cause mortality, with aortic repair treated as a competing risk.

RESULTS

Aortic area/height 10 cm2/m or greater coincided with 23/34 (68%) 5.0 to 5.4 cm and 20/24 (83%) 5.5 cm or greater aneurysms. Area/height correlated weakly with peak aneurysm stresses: for tricuspid valves, r = 0.22 circumferentially and r = 0.24 longitudinally; and for bicuspid valves, r = 0.42 circumferentially and r = 0.14 longitudinally. Age and peak longitudinal stress, but not area/height, were independent predictors of all-cause mortality (age: hazard ratio, 2.20 per 9-year increase, P = .013; peak longitudinal stress: hazard ratio, 1.78 per 73-kPa increase, P = .035).

CONCLUSIONS

Area/height was more predictive of high circumferential stresses in bicuspid than tricuspid valve aneurysms, but similarly less predictive of high longitudinal stresses in both valve types. Peak longitudinal stress, not area/height, independently predicted all-cause mortality. VIDEO ABSTRACT.

Coronary artery dilation associated with bicuspid and unicuspid aortic valve disease in children: a series of 17 patients

INTRODUCTION

Coronary artery dilation associated with bicuspid/unicuspid aortic valves is described in adults with limited data in children. We aimed to describe the clinical course of children with bicuspid/unicuspid aortic valves and coronary dilation including coronary Z-score changes over time, association of coronary changes with aortic valve anatomy/function, and complications.

MATERIALS AND METHODS

Institutional databases were searched for children ≤18 years with both bicuspid/unicuspid aortic valves and coronary dilation (1/2006-6/2021). Kawasaki disease and isolated supra-/subvalvar aortic stenosis were excluded. Statistics were descriptive with associations measured by Fisher's exact test and overlapping 83.7% confidence intervals.

RESULTS

Of 17 children, bicuspid/unicuspid aortic valve was diagnosed at birth in 14 (82%). Median age at coronary dilation diagnosis was 6.4 years (range: 0-17.0). Aortic stenosis was present in 14 (82%) [2 (14%) moderate, 8 (57%) severe]; 10 (59%) had aortic regurgitation; 8 (47%) had aortic dilation. The right coronary was dilated in 15 (88%), left main in 6 (35%), and left anterior descending in 1 (6%) with no relationship between leaflet fusion pattern or severity of aortic regurgitation/stenosis on coronary Z-score. Follow-up evaluations were available for 11 (mean 9.3 years, range 1.1-14.8) with coronary Z-scores increasing in 9/11 (82%). Aspirin was used in 10 (59%). There were no deaths or coronary artery thrombosis.

DISCUSSION

In children with bicuspid/unicuspid aortic valves and coronary dilation, the right coronary artery was most frequently involved. Coronary dilation was observed in early childhood and frequently progressed. Antiplatelet medication use was inconsistent, but no child died nor developed thrombosis.

Left ventricular myocardial work for the prediction of postoperative outcomes in patients with bicuspid aortic stenosis

Chronic elevation of left ventricular (LV) afterload contributes to adverse LV remodeling and myocardial impairment in bicuspid aortic valve (BAV) patients with severe aortic stenosis (AS). Incorporating LV afterload into global longitudinal strain (GLS) analysis, myocardial work facilitates early detection of LV dysfunction. The present study was to evaluate myocardial work in BAV patients with severe AS undergoing surgical aortic valve replacement (SAVR) and to evaluate its prognostic impact on early postoperative outcomes. Between January 2021 and March 2022, BAV patients with severe AS scheduled for SAVR were included and underwent comprehensive transthoracic echocardiography. Quantification of LV myocardial work was performed to obtain LV global work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE). Clinical outcome was defined as a composite of major cardiovascular events including mortality, myocardial infarction, stroke, acute kidney injury, low cardiac output syndrome and vascular complications during hospitalization or within 30 days after operation. Among 103 BAV patients with severe AS undergoing SAVR (mean age of 65 ± 9 years, 57.3% male), 22 experienced postoperative major cardiovascular events. BAV patients with major cardiovascular events demonstrated lower LV GWI (P < 0.001) and GCW (P = 0.002) along with elder age (P = 0.030), decreased LVGLS (P = 0.026) and right ventricular longitudinal strain (P = 0.019), and higher prevalence of abnormal average E/e' ratio (P = 0.029) than those without major events. Decreased LV GWI and GCW was independently associated with the occurrence of major cardiovascular events (P < 0.01 for adjusted OR). Multivariable logistic regression model including LV GWI demonstrated superior power than the model including LVGLS and yielded best discrimination for BAV patients with and without major cardiovascular events during early postoperative period. Echocardiography-based LV myocardial work overcomes the limitations of LVGLS and presents as a promising novel index for the early detection of functional myocardial damage and the optimization of intervention timing among BAV patients with severe AS.

Left atrial strain brings new insights for evaluating early diastolic dysfunction in patients with well-functioning bicuspid aortic valve

BACKGROUND

Left atrial reservoir strain (LARS) is an early sensor of left ventricular (LV) diastolic dysfunction. Still, the clinical implications of LARS in patients with well-functioning bicuspid aortic valve (BAV) remain unknown.

MATERIALS

The study recruited 103 patients with well-functioning BAV and 50 controls with tricuspid aortic valves. LARS, LV global longitudinal strain (LVGLS) and aortic elasticity indices (aortic strain, aortic distensibility and stiffness index) were acquired. This study aimed to analyze the changes of LARS and further explore the influential factors of LARS in patients with well-functioning BAV.

RESULTS

Patients with BAV had lower LARS (34.17 ± 4.85 vs. 44.72 ± 6.06 %, P < .001) and LVGLS (20.53 ± 1.28 vs. 22.30 ± .62 %, P < .001), and abnormal aortic elasticity indices (aortic strain:7.14 ± 1.57 vs. 10.99 ± 1.03 %, aortic distensibility: 5.82 ± 1.50 vs. 8.98 ± 2.42 (10-6 cm2 dyne-1 ), and stiffness index: 6.30 ± 2.30 vs. 3.92 ± .98, all P < .05) compared with controls. LARS was associated with LVGLS (r = .799), interventricular septum index (r = -.232), lateral e' (r = .290), septal e' (r = .308), E/e' ratio (r = -.392), aortic strain (r = .829), aortic distensibility (r = .361), and stiffness index (r = -.724) (all P < .05). LVGLS, aortic strain and E/e' ratio were independent influencers of LARS in the multifactorial analysis model (all P < .05).

CONCLUSION

In patients with well-functioning BAV, decreased LARS may provide evidence of subclinical LV diastolic function impairment. LARS may be helpful for clinical risk stratification in such a population.

2022 ACC/AHA guideline for the diagnosis and management of aortic disease: A report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2022 ACC/AHA Guideline for the Diagnosis and Management of Aortic Disease" provides recommendations to guide clinicians in the diagnosis, genetic evaluation and family screening, medical therapy, endovascular and surgical treatment, and long-term surveillance of patients with aortic disease across its multiple clinical presentation subsets (ie, asymptomatic, stable symptomatic, and acute aortic syndromes).

METHODS

A comprehensive literature search was conducted from January 2021 to April 2021, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, CINHL Complete, and other selected databases relevant to this guideline. Additional relevant studies, published through June 2022 during the guideline writing process, were also considered by the writing committee, where appropriate.

STRUCTURE

Recommendations from previously published AHA/ACC guidelines on thoracic aortic disease, peripheral artery disease, and bicuspid aortic valve disease have been updated with new evidence to guide clinicians. In addition, new recommendations addressing comprehensive care for patients with aortic disease have been developed. There is added emphasis on the role of shared decision making, especially in the management of patients with aortic disease both before and during pregnancy. The is also an increased emphasis on the importance of institutional interventional volume and multidisciplinary aortic team expertise in the care of patients with aortic disease.

Mid-term outcomes and hemodynamic performance of transcatheter aortic valve implantation in bicuspid aortic valve stenosis: Insights from the bicuSpid TAvi duraBILITY (STABILITY) registry

BACKGROUND

Limited data are available on transcatheter heart valves (THVs) durability in bicuspid aortic valve (BAV) stenosis.

AIMS

To evaluate evaluating 4-year clinical and echocardiographic outcomes of patients with BAV undergoing transcatheter aortic valve implantation (TAVI).

METHODS

The bicuSpid TAvi duraBILITY (STABILITY) registry is an Italian multicentre registry including all consecutive patients with BAV and severe aortic stenosis (AS), treated by means of TAVI between January 2011 and December 2017. Outcomes of interest were all-cause death at 4-year, over time changes in echocardiographic measurements, and THV durability according to the valve aortic research consortium (VARC)-3 update definitions.

RESULTS

Study population included 109 patients (50% females; mean age 78 ± 7.5 years) with a mean Society of Thoracic Surgeons Predicted Risk of Mortality score of 5.1 ± 4.3%. Median follow-up (FU) duration was 4.1 years [interquartile range: 2.8-5.1]. The overall cumulative incidence of all-cause death by Kaplan-Meier estimates at 4 years was 32%. Compared to baseline, a significant decrease in transprosthetic mean gradient was obtained after TAVI (54 ± 16 vs. 10 ± 5 mmHg; p < 0.001), whereas a significant increase was observed at 4-year (13 ± 6.4 mmHg, p = 0.03). Cumulative incidence of hemodynamic valve dysfunction (HVD) was 4%. Six patients met HVD criteria: three moderate and three severe HVD. All three cases of severe HVD were clinically relevant (bioprosthetic valve failure [BVF]) with two patients receiving a reintervention (TAVI in TAVI), and one patient experiencing a valve-related death due to endocarditis.

CONCLUSIONS

The STABILITY registry suggests that in patients with severe AS and BAV undergoing TAVI, postprocedural clinical benefits might last, over time, up to 4-year FU. The low rates of severe HVD and BVF may support the hypothesis of good THV durability also in BAV recipient.

Plasma Cell-Free DNA Is a Potential Biomarker for Diagnosis of Calcific Aortic Valve Disease

INTRODUCTION

Calcific aortic valve disease (CAVD) is the third most common cardiovascular disease in aging populations. Despite a growing number of biomarkers having been shown to be associated with CAVD, a marker suitable for routine testing in clinical practice is still needed. Plasma cell-free DNA (cfDNA) has been suggested as a biomarker for diagnosis and prognosis in multiple diseases. In this study, we aimed to test whether cfDNA could be used as a biomarker for the diagnosis of CAVD.

METHODS

Serum samples were collected from 137 diagnosed CAVD patients and 180 normal controls. The amount of cfDNA was quantified by amplifying a short fragment (ALU 115) and a long fragment (ALU 247) using quantitative real-time PCR. The cfDNA integrity (cfDI) was calculated as the ratio of ALU247 to ALU115. The association between CAVD and cfDI was evaluated using regression analysis.

RESULTS

CAVD patients had increased ALU 115 fragments (median, 185.14 (416.42) versus 302.83 (665.41), p < 0.05) but a decreased value of cfDI (mean, 0.50 ± 0.25 vs. 0.41 ± 0.26, p < 0.01) in their serum when compared to controls. This difference was more dramatic in non-rheumatic CAVD patients (p < 0.001) versus rheumatic CAVD patients (no significant difference). Similarly, CAVD patients with bicuspid aortic valve (BAV) (p < 0.01) showed a greater difference than non-BAV CAVD patients (p < 0.05). Linear regression and logistic regression showed that cfDI was independently and significantly associated with the presence of CAVD (95% CI, 0.096 to 0.773, p < 0.05). The ROC assay revealed that cfDI combined with clinical characteristics had a better diagnostic value than cfDI alone (AUC = 0.6191, p < 0.001).

CONCLUSION

cfDI may be a potential biomarker for diagnosis of CAVD.

Identification of immune-related signatures and pathogenesis differences between thoracic aortic aneurysm patients with bicuspid versus tricuspid valves via weighted gene co-expression network analysis

BACKGROUND

Thoracic aortic aneurysm (TAA) occurs due to pathological aortal dilation, and both individuals with normal tricuspid aortic valves (TAV) or abnormal bicuspid aortic valves (BAV), the latter being a congenital condition, are at risk. However, some differences are present between TAA/BAV and TAA/TAV with respect to their pathophysiological processes and molecular mechanisms, but their exact nature is still mostly unknown. Therefore, it is necessary to elucidate TAA developmental differences among BAV vs. TAV patients.

METHODS

Publically-available gene expression datasets, aortic tissue derived from TAA/BAV and TAA/TAV individuals, were analyzed by weighted gene co-expression network analysis (WGCNA) to identify gene modules associated with those conditions. Gene Ontology (GO) enrichment analysis was performed on those modules to identify the enriched genes within those modules, which were verified by Gene Set Variation Analysis (GSVA) on a dataset derived from aortic smooth muscle cell gene expression between TAA/TAV and TAV/BAV patients. Immune cell infiltration patterns were then analyzed by CIBERSORT, and a protein-protein interaction (PPI) network was constructed based on WGCNA and enrichment analysis results to identify hub genes, followed by validation via stepwise regression analysis. Three signatures most strongly associated with TAA/TAV were confirmed by receiver operating characteristic (ROC) and decision curve analyses (DCA) between prior-established training and testing gene sets.

RESULTS

WGCNA delineated 2 gene modules being associated with TAA/TAV vs. TAA/BAV; both were enriched for immune-associated genes, such as those relating to immune responses, etc., under enrichment analysis. TAA/TAV and TAA/BAV tissues also had differing infiltrating immune cell proportions, particularly with respect to dendritic, mast and CD4 memory T cells. Identified three signatures, CD86, integrin beta 2 (ITGB2) and alpha M (ITGAM), as yielding the strongest associations with TAA/TAV onset, which was verified by areas under the curve (AUC) at levels approximating 0.8 or above under ROC analysis, indicating their predictive value for TAA/TAV onset. However, we did not examine possible confounding variables, so there are many alternative explanations for this association.

CONCLUSIONS

TAA/TAV pathogenesis was found to be more associated with immune-related gene expression compared to TAA/BAV, and the identification of three strongly-associated genes could facilitate their usage as future biomarkers for diagnosing the likelihood of TAA/TAV onset vs. TAA/BAV, as well as for developing future treatments.

Calcium Fracture and Device Over Expansion in Transcatheter Aortic Valve Replacement for Bicuspid Aortic Valves

Transcatheter aortic valve replacement (TAVR) in patients with bicuspid aortic valve disease (BAV) has potential risks of under expansion and non-circularity which may compromise long-term durability. This study aims to investigate calcium fracture and balloon over expansion in balloon-expandable TAVs on the stent deformation with the aid of simulation. BAV patients treated with the SAPIEN 3 Ultra with pre- and post-TAVR CTs were analyzed (n = 8). Simulations of the stent deployment were performed (1) with baseline simulation allowing calcium fracture, (2) without allowable calcium fracture and (3) with balloon over expansion (1 mm larger diameter). When compared to post CT, baseline simulations had minimal error in expansion (2.5% waist difference) and circularity (3.0% waist aspect ratio difference). When compared to baseline, calcium fracture had insignificant impact on the expansion (- 0.5% average waist difference) and circularity (- 1.6% average waist aspect ratio difference). Over expansion had significantly larger expansion compared to baseline (15.4% average waist difference) but had insignificant impact on the circularity (- 0.5% waist aspect ratio difference). We conclude that stent deformation can be predicted with minimal error, calcium fracture has small differences on the final stent deformation except in extreme calcified cases, and balloon over expansion expands the waist closer to nominal values.

Variation in provider compliance with sports restriction guidelines in children with an isolated bicuspid aortic valve

BACKGROUND

Published guidelines for sports restriction for children with a bicuspid aortic valve remain controversial. We sought to describe practice variation and factors influencing sports restrictions in these children.

METHODS

This retrospective single-centre study included children (7-18 years old) with an isolated bicuspid aortic valve at baseline from 1 January, 2005 to 31 December, 2014. Sports restrictions, factors potentially influencing decision-making, and outcomes were collected. Descriptive statistics and multivariable mixed-effects logistic regression models were performed with providers and patients as random effects. Provider variation was estimated using intraclass correlation coefficients. Odds ratios, 95% confidence intervals, and p-values were reported from the models.

RESULTS

In 565 encounters (253 children; 34 providers), 41% recommended no sports restrictions, 40% recommended high-static and high-dynamic restrictions, and 19% had no documented recommendations. Based on published guidelines, 22% of children were inappropriately restricted while 30% were not appropriately restricted. The paediatric cardiology provider contributed to 37% of observed practice variation (p < 0.001). Sports restriction was associated with older age, males, greater ascending aorta z-score, and shorter follow-up interval. There were no aortic dissections or deaths and one cardiac intervention.

CONCLUSION

Physicians frequently fail to document sports restrictions for children with a bicuspid aortic valve, and documented recommendations often conflict with published guidelines. Despite this, no adverse outcomes occurred. Providers accounted for a significant proportion of the variation in sports restrictions. Further research to provide evidence-based guidelines may improve provider compliance with activity recommendations in this population.

Magnetic resonance analysis of ventricular volumes in bicuspid and trileaflet aortic regurgitation

OBJECTIVE

To identify differences in left ventricular (LV) remodelling between patients with bicuspid aortic valve (BAV) and trileaflet aortic valve (TAV) with chronic aortic regurgitation (AR).

METHODS

Retrospective cohort study of 210 consecutive patients undergoing cardiac magnetic resonance for AR evaluation. We divided the study population according to valvular morphology. Independent predictors of LV enlargement AR were evaluated.

RESULTS

There were 110 patients with BAV and 100 patients with TAV. Patients with BAV were younger (mean age BAV vs TAV: 41±16 years vs 67±11 years; p<0.01), mostly male (% male BAV vs TAV: 84.5% vs 65%, p=0.01) and presented milder degrees of AR (median regurgitant fraction BAV vs TAV: 14 (6-28)% vs 22 (12-35)%, p=0.002). Both groups presented similar indexed LV volumes and ejection fraction. According to the degree of AR, at mild AR, patients with BAV presented larger LV volumes (BAV vs TAV: indexed end diastolic left ventricular volumes (iEDV): 96.5±19.7 vs 82.1±19.3 mL, p<0.01; indexed end systolic left ventricular volumes (iESV): 39.4±10.3 mL vs 33.2±10.5 mL, p=0.01). These differences disappeared at higher degrees of AR. Independent predictors of LV enlargement were regurgitant fraction (EDV: OR 1.118 (1.081-1.156), p<0.001; ESV: OR 1.067 (1.042-1.092), p<0.001), age (EDV: OR 0.940 (0.917-0.964), p<0.001, ESV: OR 0.962 (0.945-0.979), p<0.001) and weight (EDV: OR 1.054 (1.025-1.083), p<0.001).

CONCLUSIONS

In chronic AR, LV enlargement is an early finding. LV volumes display a direct correlation with regurgitant fraction and an inverse association with age. Patients with BAV present larger ventricular volumes, especially at mild AR. However, these differences are attributable to demographic disparities; valve type is not independently associated with LV size.

The Importance of Aortic Valve Bicuspid Phenotype in Valvular Evolution in Pediatric Patients: A Case Report and Literature Mini-Review

Bicuspid aortic valve (BAV) is the most commonly encountered congenital malformation in the pediatric population, associated with aortic leaflet degeneration and aortopathy. However, studies on BAV and its complications in children are limited. We present the case of a 16-year-old with type 1B BAV with a raphe with fusion between the right and non-coronary cusps who exhibited severe aortic stenosis, regurgitation, and progressive dilatation of the ascending aorta. Surgical intervention, including aortic valve and aortic root replacement, was performed due to the patient's deteriorating condition. Histopathological examination revealed degenerative changes and calcifications in the aortic valve and mucoid fibrosis in the ascending aorta. The results are consistent with BAV patients being predisposed to aortic stenosis and regurgitation due to increased mechanical stress and hemodynamic abnormalities. Although more common in adults and a rare complication in pediatric patients, calcification was previously observed concurrently with rapid valve degeneration in our daily practice. Further studies are needed to improve our understanding of the mechanisms underlying BAV-related complications and refine treatment strategies for pediatric patients.

Family screening for bicuspid aortic valve and aortic dilatation: a meta-analysis

AIMS

International guidelines recommend screening of first-degree relatives (FDR) of people with bicuspid aortic valves (BAVs). However, the prevalence of BAV and of aortic dilatation amongst family members is uncertain.

METHODS AND RESULTS

A systematic review and meta-analysis of original reports of screening for BAV. Databases including MEDLINE, Embase, and Cochrane CENTRAL were searched from inception to December 2021 using relevant search terms. Data were sought on the screened prevalence of BAV and aortic dilatation. The protocol was specified prior to the searches being performed, and standard meta-analytic techniques were used. Twenty-three observational studies met inclusion criteria (n = 2297 index cases; n = 6054 screened relatives). The prevalence of BAV amongst relatives was 7.3% [95% confidence interval (CI) 6.1%-8.6%] overall and per family was 23.6% (95% CI 18.1%-29.5%). The prevalence of aortic dilatation amongst relatives was 9.4% (95% CI 5.7%-13.9%). Whilst the prevalence of aortic dilatation was particularly high in relatives with BAV (29.2%; 95% CI 15.3%-45.1%), aortic dilatation alongside tricuspid aortic valves was a more frequent finding, as there were many more family members with tricuspid valves than BAV. The prevalence estimate amongst relatives with tricuspid valves (7.0%; 95% CI 3.2%-12.0%) was higher than reported in the general population.

CONCLUSION

Screening family members of people with BAV can identify a cohort substantially enriched for the presence of bicuspid valve, aortic enlargement, or both. The implications for screening programmes are discussed, including in particular the substantial current uncertainties regarding the clinical implications of aortic findings.

Ex vivo biaxial load testing analysis of aortic biomechanics demonstrates variation in elastic energy distribution across the aortic zone zero

OBJECTIVES

We hypothesized that tissue characteristics vary significantly along zone zero, which may be reflected by regional differences in stored elastic energy. Our objectives were to (1) characterize the regional variation in stored elastic energy within tissues of the aortic zone zero and (2) identify the association between this variation and patient characteristics.

METHODS

From February 2018 to January 2021, 123 aortic tissue samples were obtained from the aortic root and proximal and distal ascending aortas of 65 adults undergoing elective ascending aorta replacement. Biaxial biomechanics testing was performed to obtain tissue elastic energy at the inflection point and compared with patient demographics and preoperative computed tomography imaging. Coefficient models were fit using B-spline to interrogate the relationship among elastic energy, region, and patient characteristics.

RESULTS

Mean elastic energy at inflection point was 24.3 ± 15.6 kJ/m3. Elastic energy increased significantly between the root and proximal, and root and distal ascending aorta and decreased with increasing age. Differences due to history of connective tissue disorder and bicuspid aortic valve were significant but diminished when controlled for other patient characteristics. Among covariates, age and region were found to be the most important predictors for elastic energy.

CONCLUSIONS

Aortic tissue biomechanical metrics varied across regions and with patient characteristics within the aortic zone zero. Assessment of endovascular outcomes in the ascending aorta must closely consider the region of deployment and variable tissue qualities along the length of the landing zone. Regional variation in tissue characteristics should be incorporated into existing patient-specific models of aortic mechanics.

Multimodality Imaging of Aortic Valve Calcification and Function in a Murine Model of Calcific Aortic Valve Disease and Bicuspid Aortic Valve

Calcific aortic valve disease (CAVD) is a prevailing disease with increasing occurrence and no known medical therapy. Dcbld2-/- mice have a high prevalence of bicuspid aortic valve (BAV), spontaneous aortic valve calcification, and aortic stenosis (AS). 18F-NaF PET/CT can detect the aortic valve calcification process in humans. However, its feasibility in preclinical models of CAVD remains to be determined. Here, we sought to validate 18F-NaF PET/CT for tracking murine aortic valve calcification and leveraged it to examine the development of calcification with aging and its interdependence with BAV and AS in Dcbld2-/- mice. Methods: Dcbld2-/- mice at 3-4 mo, 10-16 mo, and 18-24 mo underwent echocardiography, 18F-NaF PET/CT (n = 34, or autoradiography (n = 45)), and tissue analysis. A subset of mice underwent both PET/CT and autoradiography (n = 12). The aortic valve signal was quantified as SUVmax on PET/CT and as percentage injected dose per square centimeter on autoradiography. The valve tissue sections were analyzed by microscopy to identify tricuspid and bicuspid aortic valves. Results: The aortic valve 18F-NaF signal on PET/CT was significantly higher at 18-24 mo (P < 0.0001) and 10-16 mo (P < 0.05) than at 3-4 mo. Additionally, at 18-24 mo BAV had a higher 18F-NaF signal than tricuspid aortic valves (P < 0.05). These findings were confirmed by autoradiography, with BAV having significantly higher 18F-NaF uptake in each age group. A significant correlation between PET and autoradiography data (Pearson r = 0.79, P < 0.01) established the accuracy of PET quantification. The rate of calcification with aging was significantly faster for BAV (P < 0.05). Transaortic valve flow velocity was significantly higher in animals with BAV at all ages. Finally, there was a significant correlation between transaortic valve flow velocity and aortic valve calcification by both PET/CT (r = 0.55, P < 0.001) and autoradiography (r = 0.45, P < 0.01). Conclusion: 18F-NaF PET/CT links valvular calcification to BAV and aging in Dcbld2-/- mice and suggests that AS may promote calcification. In addition to addressing the pathobiology of valvular calcification, 18F-NaF PET/CT may be a valuable tool for evaluation of emerging therapeutic interventions in CAVD.

Familial Associations of Prevalence and Cause-Specific Mortality for Thoracic Aortic Disease and Bicuspid Aortic Valve in a Large-Population Database

BACKGROUND

Thoracic aortic disease and bicuspid aortic valve (BAV) likely have a heritable component, but large population-based studies are lacking. This study characterizes familial associations of thoracic aortic disease and BAV, as well as cardiovascular and aortic-specific mortality, among relatives of these individuals in a large-population database.

METHODS

In this observational case-control study of the Utah Population Database, we identified probands with a diagnosis of BAV, thoracic aortic aneurysm, or thoracic aortic dissection. Age- and sex-matched controls (10:1 ratio) were identified for each proband. First-degree relatives, second-degree relatives, and first cousins of probands and controls were identified through linked genealogical information. Cox proportional hazard models were used to quantify the familial associations for each diagnosis. We used a competing-risk model to determine the risk of cardiovascular-specific and aortic-specific mortality for relatives of probands.

RESULTS

The study population included 3 812 588 unique individuals. Familial hazard risk of a concordant diagnosis was elevated in the following populations compared with controls: first-degree relatives of patients with BAV (hazard ratio [HR], 6.88 [95% CI, 5.62-8.43]); first-degree relatives of patients with thoracic aortic aneurysm (HR, 5.09 [95% CI, 3.80-6.82]); and first-degree relatives of patients with thoracic aortic dissection (HR, 4.15 [95% CI, 3.25-5.31]). In addition, the risk of aortic dissection was higher in first-degree relatives of patients with BAV (HR, 3.63 [95% CI, 2.68-4.91]) and in first-degree relatives of patients with thoracic aneurysm (HR, 3.89 [95% CI, 2.93-5.18]) compared with controls. Dissection risk was highest in first-degree relatives of patients who carried a diagnosis of both BAV and aneurysm (HR, 6.13 [95% CI, 2.82-13.33]). First-degree relatives of patients with BAV, thoracic aneurysm, or aortic dissection had a higher risk of aortic-specific mortality (HR, 2.83 [95% CI, 2.44-3.29]) compared with controls.

CONCLUSIONS

Our results indicate that BAV and thoracic aortic disease carry a significant familial association for concordant disease and aortic dissection. The pattern of familiality is consistent with a genetic cause of disease. Furthermore, we observed higher risk of aortic-specific mortality in relatives of individuals with these diagnoses. This study provides supportive evidence for screening in relatives of patients with BAV, thoracic aneurysm, or dissection.

Occult deterioration of an aortic annular abscess: how do we diagnose a pseudoaneurysm periaortic valve? A case report

BACKGROUND

Infectious endocarditis (IE) is a disease caused by the colonization of toxic microorganisms on the endocardium of heart valves [1]. Although much progress has been made in the diagnosis and treatment of IE, its complications, such as annular abscesses [2], still have a high mortality rate. In this case, we describe a patient with infective endocarditis complicated by occult deteriorated aortic annular abscess.

CASE PRESENTATION

A 44-year-old man was admitted due to weakness of his right limbs and unclear speech for 10 h. He had recurrent fevers for 1 month before admission. Transthoracic echocardiography showed a mix-echoic vegetation attached to the bicuspid aortic valve, moderate aortic regurgitation and a possible aortic annular abscess. Blood cultures were negative and empiric antibiotic therapy was begun. The patient did not have fever again and seem to be clinically improved. However, follow-up transesophageal echocardiography revealed a large periaortic abscess led to aortic sinus pseudoaneurysm. The patient underwent mechanical prosthetic valve replacement and annulus reconstruction successfully. Perivalvular abscess may be insidious deterioration in patients who seem to be clinically improved, which requires us to pay more attention.

DISCUSSION

Occult deterioration of an aortic annular abscess is rare and more attention should be paid. Re-evaluation of echocardiography is required even if the patient's symptoms improve.

Anatomical mapping of the membranous septum in tricuspid and bicuspid aortic valves by cardiac computed tomography

A higher incidence of conduction disturbances and permanent pacemaker implantation (PPI) has been observed after transcatheter aortic valve implantation (TAVI) in patients with bicuspid aortic valves (BAVs) as compared to those with tricuspid aortic valves (TAVs). This study aimed to provide an anatomical explanation for this observation, supported by an in-depth anatomical mapping of the membranous septum (MS) in a large cohort of BAVs and TAVs using cardiac computed tomography (CT). A total of 300 cardiac CT scans were analysed, revealing a significantly shorter sub-annular length of the MS in BAVs at all measuring points compared to TAVs (p < 0.001). In the current BAV cohort, the MS was found to be at its shortest at the RCC site, measuring less than 1 mm in depth. In addition, the MS was located more anteriorly towards the RCC in BAVs, where the transcatheter aortic valve tends to be implanted deeper, and we observed a trend towards a higher PPI rate in BAVs. Future studies should investigate whether anatomical mapping of the MS in patients undergoing TAVI could be a useful tool for decision-making and potentially mitigate the risk of conduction disturbances.

Novel Association of the NOTCH Pathway Regulator MIB1 Gene With the Development of Bicuspid Aortic Valve

Importance

Nonsyndromic bicuspid aortic valve (nsBAV) is the most common congenital heart valve malformation. BAV has a heritable component, yet only a few causative genes have been identified; understanding BAV genetics is a key point in developing personalized medicine.

Objective

To identify a new gene for nsBAV.

Design, Setting, and Participants

This was a comprehensive, multicenter, genetic association study based on candidate gene prioritization in a familial cohort followed by rare and common association studies in replication cohorts. Further validation was done using in vivo mice models. Study data were analyzed from October 2019 to October 2022. Three cohorts of patients with BAV were included in the study: (1) the discovery cohort was a large cohort of inherited cases from 29 pedigrees of French and Israeli origin; (2) the replication cohort 1 for rare variants included unrelated sporadic cases from various European ancestries; and (3) replication cohort 2 was a second validation cohort for common variants in unrelated sporadic cases from Europe and the US.

Main Outcomes and Measures

To identify a candidate gene for nsBAV through analysis of familial cases exome sequencing and gene prioritization tools. Replication cohort 1 was searched for rare and predicted deleterious variants and genetic association. Replication cohort 2 was used to investigate the association of common variants with BAV.

Results

A total of 938 patients with BAV were included in this study: 69 (7.4%) in the discovery cohort, 417 (44.5%) in replication cohort 1, and 452 (48.2%) in replication cohort 2. A novel human nsBAV gene, MINDBOMB1 homologue MIB1, was identified. MINDBOMB1 homologue (MIB1) is an E3-ubiquitin ligase essential for NOTCH-signal activation during heart development. In approximately 2% of nsBAV index cases from the discovery and replication 1 cohorts, rare MIB1 variants were detected, predicted to be damaging, and were significantly enriched compared with population-based controls (2% cases vs 0.9% controls; P = .03). In replication cohort 2, MIB1 risk haplotypes significantly associated with nsBAV were identified (permutation test, 1000 repeats; P = .02). Two genetically modified mice models carrying Mib1 variants identified in our cohort showed BAV on a NOTCH1-sensitized genetic background.

Conclusions and Relevance

This genetic association study identified the MIB1 gene as associated with nsBAV. This underscores the crucial role of the NOTCH pathway in the pathophysiology of BAV and its potential as a target for future diagnostic and therapeutic intervention.

Serum endocan levels in children with rheumatic aortic insufficiency: can it differentiate bicuspid aortic valve disease from rheumatic heart disease?

AIM

In this study, it was aimed to examine the serum endocan levels in patients with rheumatic aortic regurgitation and to investigate whether it has a value in differentiating it from aortic regurgitation due to bicuspid aortic valve.

METHODS

Blood samples were collected from patients with rheumatic aortic regurgitation (Group 1), incidentally diagnosed patients with borderline or definite rheumatic aortic regurgitation (Group 2), children with bicuspid aortic valve accompanied by aortic regurgitation (Group 3) and healthy children (Group 4) of similar age.

RESULTS

There were 12 children in Group 1, 13 in Group 2, 25 in Group 3, and 25 in Group 4. Groups were similar in terms of age (p = 0.291). There was no statistically significant difference between median serum endocan levels of Group 1 and Group 2 (p = 0.624), and Group 3 and Group 4 (p = 0.443). Despite that, the median serum endocan levels of Group 1 and Group 2 were significantly higher than that of both Group 3 and Group 4 (p = 0.000 for all).

CONCLUSIONS

Our results indicate that serum endocan level can be used to differentiate rheumatic aortic regurgitation from non-rheumatic aortic regurgitation. It is thought that the prognostic role of this marker should be confirmed in long-term, prospective studies with larger samples.