Bicuspid Aortic Valve Patients Research Articles

Abstract 4141445: Long-Term Predictive Value of 4D Flow MRI in Bicuspid Aortic Valve Patients: A 10-Year Assessment for Aortic Surgery Risk

Introduction: Bicuspid aortic valve (BAV) is associated with progressive ascending aorta (AAo) dilation, often leading to aneurysms, dissections, and ruptures. Thus, current guidelines recommend preventive surgery for AAo dilation. Recent 4D flow MRI studies show that BAV morphology causes abnormal transvalvular flow patterns, increasing wall shear stress (WSS), a trigger of aortic growth. Further studies have delineated areas of abnormally high WSS by comparing to estimates of matched controls, and show promise in detecting risk for aortic growth. However, since the long-term prognostic significance of this marker is unclear, we aimed to quantify WSS in BAV patients to assess its value in predicting the need for aortic surgery up to 10 years post-4D flow MRI acquisition. Methods: BAV patients without prior surgical intervention scanned before April 1, 2014 were identified. Using medical records, patients were categorized as ‘operated’ if they underwent aortic surgery post-scan and ‘non-operated’ if they were surgery-free for at least 10 years post-scan. 4D flow MRIs were processed with an AI pipeline, including 3D segmentation of the aorta, followed by peak velocity (PV) and WSS quantification in the AAo (Fig. 1A-C). Patient-specific WSS heatmaps were computed relative to a map based on the WSS of 10 or more sex and age-matched controls. Relative areas of elevated WSS in the AAo were then calculated (Fig. 1D-F). Results: 115 patients were included, with 73 non-operated (age: 42.5±11.5y, 49M) and 42 operated patients (age: 53.5±12.1y, 34M). The mean baseline mid-AAo diameters for non-operated and operated patients were 3.8±0.6 cm and 4.1±0.5 cm, respectively. Among operated patients, the mean scan to surgery time was 5.7±3.3y. All three 4D flow metrics were significantly higher in operated compared to non-operated patients: PV: 2.6±0.6 vs. 1.7±0.4 m/s (p<0.01); WSS: 2.2±0.5 vs. 1.6±0.4 Pa (p<0.01); relative area of high WSS on heatmaps: 31±12 vs. 15±13% (p<0.01). Conclusions: 4D flow MRI parameters provide long-term predictive value in BAV patients, as elevated peak velocity, wall shear stress, and relative area of high wall shear stress on heatmaps are associated with subsequent aortic surgery within 10 years post-scan.

Abstract 4123806: Early Findings on the Impact of Renin-Angiotensin-Aldosterone System Inhibitors on Bicuspid Aortic Valve Disease Progression: A Single Center Cohort Study

Introduction: Patients with a bicuspid aortic valve (BAV) often have an associated aortopathy, increasing their risk of aortic dissection. Currently, there is no proven therapy to stabilize the growth of BAV aortopathy. This study aimed to assess the effect of cardioprotective medications, specifically renin-angiotensin-aldosterone system inhibitors (RAASi), on the progression of aortic dilation in adult BAV patients. Methods: A retrospective cohort study was conducted including adult patients with BAV followed at our center between 1996-2020. All patients had echocardiography imaging with at least 5 years of follow-up. The cohort was divided based on the chronic use of RAASi, as determined by pharmacy check-out data. The primary endpoint was defined as either the progression of ascending aortic diameter ≥ 4.5 cm or surgery for ascending aortic replacement. Results: The study included 262 patients with a mean age of 54.3±19.5 years, of whom 75.2% (n=197) were male, and 34.7% (n=44) had a diagnosis of hypertension. At baseline, the average size of the ascending aorta was 4.2±4.1 mm and 3.5±4.0 mm at the level of the aortic sinuses. The average follow-up time was 5.8±0.8 years. During follow-up, 23 patients underwent ascending aortic replacement with concurrent aortic valve replacement, 66 patients experienced progression of ascending aortic diameter ≥ 4.5 cm, and 2 patients died. Patients using RAASi (n=40) had a lower incidence of the primary endpoint compared to those without RAASi chronic therapy (12.8% vs. 24.8%, p=0.147). Multivariate analysis indicated that patients without RAASi chronic therapy had a significantly increased risk of the primary endpoint (HR=2.87, 95% CI [1.03-8.01], p=0.43). Conclusions: Our early findings suggest that RAASi may have a preventative role in the progression of BAV aortopathy.

Association between silent cerebral embolism and cognitive alterations following transcatheter aortic valve replacement in bicuspid versus tricuspid aortic valve patients

Abstract Background Silent cerebral ischemic lesions (SCILs) is a common magnetic resonance imaging (MRI) finding in severe aortic stenosis patients post - transcatheter aortic valve replacement (TAVR). We evaluated the association between SCILs and cognitive alterations in patients with bicuspid aortic valve (BAV) versus tricuspid aortic valve (TAV) post-TAVR. Methods This study enrolled 100 consecutive TAVR (45 with BAV and 55 TAV). DW-MRI and neurocognitive evaluation (MoCA score) were performed at baseline, discharge, and 1- and 12-month post-discharge. Results Ninety-two out of the 100 patients (92%) exhibited cognitive dysfunction at baseline. Post-TAVR, overall cognitive function significantly improved, the average MOCA score increased from 18.69±6.74 to 22.18±6.30. During the 1-year follow-up, 54 patients demonstrated improved cognitive function, and the number of patients with moderate-to-severe cognitive dysfunction (MoCA score < 18) significantly decreased from 32 to 16. Prevalence of SCILs was 14% and 72% at baseline and discharge, respectively. New SCILs were observed in 60 patients at discharge, distributed across all vascular territories, averaging 4 lesions with a total volume of 215.4±195.4mm3. Although no significant correlation existed between total volume of new SCILs and cognitive changes post-TAVR (R=-0.133, p=0.206), patients with SCILs still displayed significant cognitive improvement (MoCA score from 18.4±6.6 to 22.0±7.1), whereas patients who developed large SCILs (lesion diameter >9) showed less improvement compared to those with small or median SCILs (number of patients who had cognitive improvement: 32 vs. 52, p<0.05). Cognitive function improvement post-TAVR did not significantly differ between BAV and TAV patients, MoCA scores were comparable (BAV group, n=45, from 18.63±6.68 to 21.88±6.80 vs. TAV group, n=55, from 18.73±6.81 to 22.42±5.80; p>0.05). DW-MRI revealed more new SCILs in BAV patients post-TAVR compare to TAV patients (235 lesions vs. 150 lesions, respectively). In BAV patients, SCILs primarily manifested in small and medium sizes (224 lesions), despite more severe calcification (valvular calcium volume 956.5±644.0 mm vs. 634.4±508.0 mm3; p=0.028). The number of large lesions was similar in the two groups (11 in BAV group and 10 in TAV group). Conclusion TAVR demonstrates positive effects on improving cognitive function in aortic stenosis patients, despite common occurrence of SCILs in both BAV and TAV patients. Cognitive function post-TAVR was comparable between BAV and TAV patients. The cognitive improvement from TAVR may be less impacted by small- and medium-sized SCILs, while severe SCILs might impede or diminish the cognitive benefits of TAVR.table

Conduction Disturbances and Outcome After Surgical Aortic Valve Replacement in Patients With Bicuspid and Tricuspid Aortic Stenosis.

This study aimed to compare the incidence and prognostic implications of new-onset conduction disturbances after surgical aortic valve replacement (SAVR) in patients with bicuspid aortic valve (BAV) aortic stenosis (AS) versus patients with tricuspid aortic valve (TAV) AS (ie, BAV-AS and TAV-AS, respectively). Additionally, the study included stratification of BAV patients according to subtype. In this cohort study, the incidence of postoperative third-degree atrioventricular (AV) block with subsequent permanent pacemaker requirement and new-onset left bundle-branch block (LBBB) was investigated in 1147 consecutive patients without preoperative conduction disorder who underwent isolated SAVR (with or without ascending aortic surgery) between January 1, 2005, and December 31, 2022. The groups were stratified by aortic valve morphology (BAV, n=589; TAV, n=558). The outcomes of interests were new-onset third-degree AV block or new-onset LBBB during the index hospitalization. The impact of new-onset postoperative conduction disturbances on survival was investigated in BAV-AS and TAV-AS patients during a median follow-up of 8.2 years. BAV morphology was further categorized according to the Sievers and Schmidtke classification system (possible in 307 BAV-AS patients) to explore association between BAV subtypes and new-onset conduction disturbances after SAVR. The overall incidence of third-degree AV block and new-onset LBBB after SAVR was 4.5% and 7.8%, respectively. BAV-AS patients had a higher incidence of both new-onset third-degree AV block (6.5% versus 2.5%; P=0.001) and new-onset LBBB (9.7% versus 5.7%; P=0.013) compared with TAV-AS patients. New-onset LBBB was associated with an increased all-cause mortality during follow-up (adjusted hazard ratio, 1.60 [95% CI, 1.12-2.30]; P=0.011), whereas new-onset third-degree AV block was not associated with worse prognosis. Subgroup analysis of the BAV cohort revealed that BAV-AS patients with fusion of the right- and non-coronary cusps had the highest risk of new-onset third-degree AV block (adjusted odds ratio [aOR], 8.33 [95% CI, 3.31-20.97]; P<0.001, with TAV as reference group) and new-onset LBBB (aOR, 4.03 [95% CI, 1.84-8.82]; P<0.001, with TAV as reference group), whereas no significant association was observed for the other BAV subtypes. New-onset LBBB after SAVR is associated with increased all-cause mortality during follow-up, and is more frequent complication in BAV AS patients compared with TAV-AS patients. BAV-AS patients with fusion of the right- and non-coronary cusps have an increased risk for conduction disturbances after SAVR. This should be taken into consideration when managing these patients.

Aortic root replacement for bicuspid aortic valve dysfunction does not impair survival rates

BackgroundPatients with a bicuspid aortic valve carry an increased risk for developing an ascending aortic aneurysm due to intrinsic aortic wall alterations. A lower threshold for aortic surgery may therefore be considered in these patients, especially in those who require aortic valve surgery. This study aimed to compare the outcomes of an isolated aortic valve replacement with that of an aortic root replacement in bicuspid aortic valve patients with an indication for aortic valve surgery.MethodsPatients were included in retrospect from a tertiary academic hospital. Included patients received an elective aortic valve (AVR) or a composite valve-graft conduit (both mechanical and biological) between 2006 and 2021 without any concomitant procedure. Mortality data were retrieved from a national database and comparisons, including survival analyses, were performed between both groups.ResultsA total of 132 isolated AVR and 149 aortic root replacements were included. Patients who received an isolated AVR were significantly older than the aortic root replacement group (62.9 vs. 57.7 year respectively, p < 0.001). Survival analyses showed a comparable long-term mortality between both groups (8.1% vs. 9.1%, p = 0.321).ConclusionThis study shows that performing an aortic root replacement with a composite valve-graft conduit in bicuspid aortic valve patients does not impair the survival outcomes. In the light of preventing potential future aortic complications within this patient group with a congenitally and structurally weakened aortic wall, a more aggressive approach towards the treatment of BAV aortopathy might be considered.

Interrupted aortic arch with severe aortic stenosis in an adult bicuspid aortic valve patient

Interrupted aortic arch with severe aortic stenosis in an adult bicuspid aortic valve patient

Greater TIMP-1 protein levels and neointimal formation represent sex-dependent cellular events limiting aortic vessel expansion in female rats.

Fragmentation/loss of the structural protein elastin represents the precipitating event translating to aortic expansion and subsequent aneurysm formation. The present study tested the hypothesis that greater protein expression of tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) and neointimal growth secondary to a reduction of medial elastin content represent sex-dependent events limiting aortic vessel expansion in females. TIMP-1 protein levels were higher in the ascending aorta of female versus male patients diagnosed with a bicuspid aortic valve (BAV). The latter paradigm was recapitulated in the aorta of adult male and female rats complemented by greater TIMP-2 expression in females. CaCl2 (0.5 M) treatment of the infrarenal aorta of adult male and female rats increased the in situ vessel diameter and expansion was significantly smaller in females despite a comparable reduction of medial elastin content. The preferential appearance of a neointimal region of the CaCl2-treated infrarenal aorta of female rats may explain in part the smaller in situ expansion and neointimal growth correlated positively with the % change of the in situ diameter. Neointimal formation was secondary to a significant increase in the density of medial/neointimal vascular smooth muscle cells (VSMCs) that re-entered the G2-M phase whereas VSMC cell cycle re-entry was attenuated in the CaCl2-treated infrarenal aorta of male rats. Thus, greater TIMP-1 expression in the aorta of female BAV patients may prevent excessive elastin fragmentation and preferential neointimal growth following CaCl2-treatment of the infrarenal aorta of female rats represents a sex-dependent biological event limiting vessel expansion secondary to a significant loss of the structural protein.

Assessment of abnormal transvalvular flow and wall shear stress direction for pediatric/young adults with bicuspid aortic valve: a cross-sectional 4D flow study

BackgroundAortic dilation is seen in pediatric/young adult patients with bicuspid aortic valve (BAV), and hemodynamic markers to predict aortic dilation are necessary for monitoring. Although promising hemodynamic metrics, such as abnormal wall shear stress (WSS) magnitude, have been proposed for adult BAV patients using 4D flow cardiovascular magnetic resonance, those for pediatric BAV patients have less frequently been reported, partly due to scarcity of data to define normal WSS range. To circumvent this challenge, this study aims to investigate if a recently proposed 4D flow-based hemodynamic measurement, abnormal flow directionality, is associated with aortic dilation in pediatric/young adult BAV patients. Methods4D flow scans for BAV patients (<20 years old) and age-matched controls were retrospectively enrolled. Static segmentation for the aorta and pulmonary arteries was obtained to quantify peak systolic hemodynamics and diameters in the proximal aorta. In addition to peak velocity, wall shear stress (WSS), vorticity, helicity, and viscous energy loss, direction of aortic velocity and WSS in BAV patients was compared with that of control atlas using registration technique; angle differences of >60deg and >120deg were defined as moderately and severely abnormal, respectively. Association between the obtained metrics and normalized diameters (Z-scores) were evaluated at the sinotubular junction, mid ascending aorta, and distal ascending aorta. ResultsFifty-three BAV patients, including eighteen with history of repaired aortic coarctation, and seventeen controls were enrolled. Correlation between moderately abnormal velocity/WSS direction and aortic Z-scores was moderate to strong at the sinotubular junction and mid ascending aorta (R=0.62-0.81; p<0.001) while conventional measurements exhibited weaker correlation (|R|=0.003-0.47, p=0.009-0.99) in all subdomains. Multivariable regression analysis found moderately abnormal velocity direction and existence of aortic regurgitation (only for isolated BAV group) were independently associated with mid ascending aortic Z-scores. ConclusionAbnormal velocity and WSS directionality in the proximal aorta was strongly associated with aortic Z-scores in pediatric/young adult BAV patients.

Infective Endocarditis in Patients With Bicuspid Aortic Valves: Unique Clinical and Microbiologic Features

Patients with bicuspid aortic valves (BAV) are at increased risk of infective endocarditis (IE). Information of the clinical presentation and the microbiology of BAV-associated IE, however, is limited. Therefore, our study aimed to characterise the clinical features native valve endocarditis (NVE) in the setting of BAV and compared them to patients with prosthetic valve endocarditis (PVE) following BAV replacement. Adult patients with BAV or history of BAV with aortic valve replacement (AVR) and a definite or possible IE diagnosis within the Mayo Clinic Enterprise (USA) from January 2008 to December 2021, were included. BAV was confirmed by trans-oesophageal echocardiography. IE was defined according to the modified Duke criteria and only an initial episode was included. Statistical analyses were performed to compare clinical characteristics, microbiology, and IE complications. Overall, 161 patients with BAV and IE (NVE [n=60], 37.3%) and PVE [n=101, 62.7%) were included. Mean age±SD was 56.5±16.1 years, and 139 (86.3%) patients were males. PVE patients were older (p<0.01) and had a higher rate of hypertension (p<0.01), chronic heart failure (p<0.01), chronic kidney disease (p<0.01), and perivalvular abscess (p<0.01). BAV patients with NVE had a higher prevalence of isolated mitral valve IE (p<0.01), moderate to severe aortic valve regurgitation (p<0.01) and combined aortic with mitral valve IE (p<0.01). Streptococcus mitis was the most common pathogen in NVE (30.0%) while Staphylococcus aureus was the most common in PVE (15.8%). Patients with BAV are at risk of both NVE and PVE. Each syndrome has unique clinical features, including microbiologic findings, that should be appreciated in IE diagnosis and management.

Two-year follow-up of transcatheter aortic valve replacement in low-risk patients with symptomatic severe bicuspid aortic valve stenosis.

In 2019, the US Food and Drug Administration (FDA) approved transcatheter aortic valve replacement (TAVR) for low-risk patients with symptomatic severe tricuspid aortic stenosis. However, bicuspid aortic valve (BAV) patients were included only in single-arm registries of pivotal low-risk TAVR trials, resulting in limited data for this subgroup. The LRT (Low Risk TAVR) trial was an investigator-initiated, prospective, multicenter study and the firstFDA-approved investigational device exemption trial to evaluate the feasibility of TAVR with balloon-expandable or self-expanding valves in low-risk patients with symptomatic severe BAV stenosis. This analysis reports 2-year follow-up, assessing the primary outcome of all-cause mortality and evaluating clinical outcomes. From 2016 to 2019, a total of 72 low-risk patients diagnosed with symptomatic, severe BAV stenosis underwent TAVR across six centers. Six patients were lost to follow-up. At 2-year follow-up, mortality was 1.5% (1 of 66 patients). Among the remaining 65 patients, four experienced nondisabling strokes (6.2%), while 2 (3.1%) developed infective endocarditis. No new permanent pacemakers were required beyond the 30-day follow-up, and no patients, including those with endocarditis, needed aortic valve re-intervention. At the 2-year echocardiography follow-up (n = 65), 27.8% of BAV patients showed mild aortic regurgitation, with none exhibiting moderate or severe regurgitation. The mean aortic gradient was 12.1 ± 4.1 mmHg, and the mean valve area was 1.7 ± 0.5 cm². The 2-year follow-up confirms commendable clinical outcomes of TAVR in patients with bicuspid aortic stenosis, establishing its evident safety.

Indexed aortic valve area using multimodality imaging for assessing the severity of bicuspid aortic stenosis

BackgroundThe impact of various imaging modalities on discordance/concordance between indexed aortic valve area (iAVA) and catheterization-derived mean transaortic pressure gradient (mPGcath) is unclear in patients with bicuspid aortic valve (BAV). This study aimed to compare iAVA measurements obtained using four different methodologies in BAV and tricuspid aortic valve (TAV) patients, using mPGcath as a reference standard. MethodsWe retrospectively reviewed patients who underwent comprehensive assessment of AS, including two-dimensional (2D) transthoracic echocardiography (TTE), three-dimensional (3D) transesophageal echocardiography (TEE), multidetector computed tomography (MDCT), and catheterization, at our institution between 2019 and 2022. iAVA was measured using the continuity eq. (CE) with left ventricular outflow tract area obtained by 2D TTE, 3D TEE, and MDCT, as well as planimetric 3D TEE. Results and ConclusionsAmong 564 patients (64 with BAV and 500 with TAV), 64 propensity-matched pairs of patients with BAV and TAV were analyzed. iAVACE(2DTTE) led to overestimation of AS severity (BAV, 23.4%; TAV, 28.1%) and iAVACE(MDCT) led to underestimation of AS severity (BAV, 29.3%; TAV, 16.7%), whereas iAVACE(3DTEE) and iAVAPlani(3DTEE) resulted in a reduction in the discordance of AS grading. A moderate correlation was observed between mPGcath and iAVACE(3DTEE) (BAV, r = −0.63; TAV, r = −0.68), with iAVACE(3DTEE) corresponding to the current guidelines' cutoff value (BAV, 0.58 cm2/m2; TAV, 0.60 cm2/m2). Discordance/concordance between iAVA and mPGcath in evaluating AS severity varies depending on the methodology and imaging modality used. The use of iAVACE(3DTEE) is valuable for reconciling the discordant AS grading in BAV patients as well as TAV.

Prognostic value of the electrocardiogram in patients with bicuspid aortic valve disease

BackgroundIdentifying bicuspid aortic valve (BAV) patients at risk for cardiac events remains challenging and the role of the electrocardiogram (ECG) has not yet been described. Therefore, this study aims to describe ECG parameters in BAV patients, and investigate their prognostic value. MethodsIn this single-center prospective study patients with BAV without a prior aortic valve replacement (AVR) were included. Transthoracic echocardiogram and 12‑lead resting-ECG were obtained. Associations between ECG parameters and the composite endpoint of all-cause mortality and AVR were assessed using Cox-proportional hazard analysis. Results120 patients with BAV were included (median age 30 years, 61% male). Median aortic jet velocity was 2.4 m/s [IQR: 1.7–3.4] and 5 patients (4%) had severe aortic regurgitation. All patients were in sinus rhythm. Any ECG abnormality was present in 57 patients (48%). Median PR-interval was 156 [IQR: 138–170] msec. A deviating QRS axis was found in 17 patients (14%) and Cornell criteria for LVH were fulfilled in 20 patients (17%). Repolarization abnormalities were present in 12 patients (10%). Median follow-up duration was 7.0 [6.3–9.8] years, during which 23 patients underwent AVR and 2 patients died. After adjusting for age, a longer PR-interval was associated with worse intervention-free survival (HR 1.02, 95% CI: 1.01–1.04). ConclusionAlmost half of the patients with BAV had abnormalities on their ECG. Moreover, the PR-interval may be an interesting prognostic marker for intervention-free survival in BAV patients.

Bicuspid Aortic Valve Function and Aortopathy on Presentation and Progression in Children: Does Sex Difference Have Any Implications?

Bicuspid aortic valve (BAV) is the most common congenital heart defect. It can be accompanied by aortic regurgitation or stenosis with aortopathies. Studies in adults showed a sex difference, but there are limited number of reports in the pediatric population. To evaluate the difference in bicuspid aortic valve morphology and functionality between sexes, and the presence and progression of aortopathies, a retrospective chart review study was performed at a tertiary referral care center in the Midwest. In our study, we analyzed a cohort of 476 pediatric patients diagnosed with BAV who presented between January 2007 and February 2018. During the follow-up period spanning 2 to 10years, male patients (n = 314, 66%) had larger aortic valve annulus (AVA) and sinus of Valsalva (SOV) at the time of initial presentation with more likelihood for progression. In the subgroup analysis, the larger SOV in males was observed in isolated BAV patients without genetic syndromes or cardiac malformations, and there were no significant differences between both sexes in the ascending aorta dimension, valve functionality, valve morphology, and the need for intervention in any of the studied groups. As such, these findings may alter the follow-up focus and frequency for patients with BAV, particularly before adulthood, and warrant further studies.

Smooth muscle cell phenotypic switching occurs independent of aortic dilation in bicuspid aortic valve-associated ascending aortas.

Bicuspid aortic valves (BAV) are frequently associated with ascending aortic aneurysms. The etiology is incompletely understood, but genetic factors, in addition to flow perturbations, are likely involved. Since loss of contractility and elaboration of extracellular matrix in the vessel wall are features of BAV-associated aortopathy, phenotypic modulation of smooth muscle cells (SMCs) may play a role. Ascending aortic tissue was collected intra-operatively from 25 individuals with normal (i.e., tricuspid) aortic valves (TAV) and from 25 individuals with BAVs. For both TAV and BAV, 10 patients had non-dilated (ND) and 15 patients had dilated (D) aortas. SMCs were isolated and cultured from a subset of patients from each group. Aortic tissue and SMCs were fluorescently immunolabeled for SMC phenotypic markers (i.e., alpha-smooth muscle actin (ASMA, contractile), vimentin (synthetic) and p16INK4a and p21Cip1 (senescence). SMCs were also analyzed for replicative senescence in culture. In normal-sized and dilated BAV aortas, SMCs switched from the contractile state to either synthetic or senescent phenotypes, as observed by loss of ASMA (ND: P = 0.001, D: P = 0.002) and associated increases in vimentin (ND: P = 0.03, D: P = 0.004) or p16/p21 (ND: P = 0.03, D: P<0.0001) compared to TAV. Dilatation of the aorta exacerbated SMC phenotypic switching in both BAV and TAV aortas (all P<0.05). In SMCs cultured from normal and dilated aortas, those isolated from BAV reached replicative senescence faster than those from TAV aortas (all P = 0.02). Furthermore, there was a stark inverse correlation between ASMA and cell passage number in BAV SMCs (ND: P = 0.0006, D: P = 0.01), but not in TAV SMCs (ND: P = 0.93, D: P = 0.20). The findings of this study provide direct evidence from cell culture studies implying that SMCs switch from the contractile state to either synthetic or senescent phenotypes in the non-dilated BAV aorta. In cultured SMCs from both non-dilated and dilated aortas, we found that this process may precede dilatation and accompany aneurysm development in BAV. Our findings suggest that therapeutically targeting SMC phenotypic modulation in BAV patients may be a viable option to prevent or delay ascending aortic aneurysm formation.

TAVR with self- expandable valves: what challenges in bicuspid aortic valve disease?

Background: The bicuspid aortic valve (BAV) represents a complex anatomic entity for transcatheter aortic valve replacement (TAVR) because of its unique technical challenges. All the randomized clinical trials comparing outcomes of TAVI with surgery till date, have excluded patients with bicuspid aortic valve. The only data in literature come from empirical observations, with large variability in implantation techniques across different centers and operators. Objective: These case reports describe the results of transcatheter aortic valve replacement (TAVR) in bicuspid aortic valve stenosis (BAV) using self-expandable valves with their clinical, imaging, procedural, and follow-up settings. Case reports: We report 3 cases of TAVR with BAV. The patients were at high risk of surgery. Baseline cardiac computed tomography (CT) was analyzed by interventional cardiologists. We used self-expandable valves in all the procedures. There were no cases of valve embolization or need for a second valve, no post-dilatation, no cases of moderate or severe aortic regurgitation, and none of the cases required a permanent pacemaker implantation. Conclusion: With the available observational data, it seems that TAVI is indeed technically feasible in selected BAV patients with acceptable results. Self-expandable valves can be safe and effective devices for these procedures. Most of the current data studies highlight the importance of preprocedural imaging determining the outcome of TAVI in BAV patients. Advancements device iterations and procedural refinements will continue to improve the outcomes of these patients treated by TAVR.

Metabolic plasma signatures in thoracic aortic aneurysm associated to tricuspid and bicuspid aortic valves

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Instituto de Salud Carlos III with co-funding from the ERDF and Comunidad de Madrid Background/Introduction Thoracic aortic aneurysm (TAA) develops asymptomatic with life-threatening consequences and its diagnosis is usually fortuitous. TAA is mostly idiopathic, although its prevalence is significantly higher in subjects with bicuspid aortic valve (BAV) for unknown reasons. We hypothesize that it is essential to investigate idiopathic TAA by differentiating between BAV and tricuspid aortic valve (TAV) patients for personalized diagnosis and treatment. Purpose We aimed to identify plasma metabolic profiles of aortic dilatation in idiopathic TAA, differentiating between subjects with BAV or TAV. Methods Plasma samples from 41 idiopathic TAA patients and 57 subjects without aortic dilatation (control, C) were collected and classified according to aortic valve type (BAV or TAV). Full metabolomics coverage was carried out by 1H RMN and LC-MS/MS untargeted analysis, including reverse phase and hydrophilic interaction chromatography and positive and negative electrospray ionization modes. Significant variation in metabolite levels were considered if FDR-adjusted p-value &amp;lt;0.05. Results Our analyses highlighted a metabolic signature specific for BAV and TAV subjects. BAV patients presented a marked glycerophospholipid metabolism alteration involving different lysophospholipids (LPAs, LPCs and LPEs) and phospholipids (PCs, PEs, PAs and PIs). Particularly, LPCs and LPEs were increased in BAV-TAA vs BAV-C, being an indicator of stimulation of glucose utilization through glycolysis and suppression of fatty acid biosynthesis. In contrast, carnitine-related metabolism was the most altered pathway observed in TAV subjects. In particular, we detected an increment in plasma acylcarnitines in TAV-TAA compared to TAV-C suggesting an altered β-oxidation of fatty acids and mitochondrial overload. Conclusions Idiopathic TAA development is differentially reflected in plasma from BAV and TAV patients, supporting an individualized diagnosis valve-dependent and suggesting also differential therapeutic targets.

Spatially resolved metabolomics revealed specific nucleotide alterations within the media and adventitia layers in idiopathic thoracic aortic aneurysms associated with tricuspid and bicuspid valves

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): Instituto de Salud Carlos III co-supported by FEDER grants and co-funded by the European Union Background Thoracic aortic aneurysms (TAAs) curse silently and asymptomatic. The vast majority are idiopathic, representing 80-95% of the cases. Nevertheless, there is an association between TAA and the presence of bicuspid aortic valve (BAV) constituting BAV an independent risk factor of TAA. The presence of BAV accelerates the growth of the aneurysm affecting younger patients than those with tricuspid aortic valve (TAV). Evidence points to a profound remodeling of the media and adventitia layers, but the underlying mechanisms are unknown, especially the metabolic changes taking place and their in situ localization. Purpose Our aim was to identify, in a spatially resolved manner, the in situ metabolic alterations occurring in TAA human aortas while differentiating between BAV and TAV patients. In a further step, we sought to identify the changes happening particularly within the media and adventitia layers. Methods Mass spectrometry imaging (MSI) was applied to identify metabolic differences between human aortas with (TAA) and without (C) dilatation classified according to their aortic valve and obtained from cardiac surgeries. Clinical groups consisted on TAV-C (n=11), BAV-C (n=12), TAV-TAA (n=12) and BAV-TAA (n=12). Subsequent virtual microdissection histologically guided was applied to identify the specific metabolic changes located within media and/or adventitia. Changes were considered significant if FDR&amp;gt;2 and p-value &amp;lt;0.05. Results Purine metabolism resulted altered in BAV-TAA patients while no differences were found in TAV-TAA ones. Particularly, we detected a significant increase of aortic ATP (FC= 2.92; p-value= 0.030), ADP (FC= 2.04; p-value= 0.020), AMP (FC= 2.42; p-value= 0.011) and GDP (FC= 2.29; p-value= 0.046) in BAV-TAA vs. BAV-C subjects. In contrast, we found an in situ increment in pyrimidine metabolism resulting UDP and UMP increased in both, TAV and BAV associated TAAs. When comparing the arterial layers, media layer was found to be the major driver of BAV-TAA with no nucleotides changes in adventitia. However, TAV-TAA media and adventitia layer behave similarly with the exception of a massive increase of ATP (FC=50.23, p=0.046) in adventitia with no alteration in media of TAV-TAA vs. TAV-C patients. Conclusions Idiopathic TAAs course differently in subjects with bicuspid and tricuspid valves both in terms of mechanisms of action and arterial remodeling within the aortic layers. These findings suggest that TAA patients with bicuspid or tricuspid aortic valve should be treated as independent groups for optimal disease management.

3D Characterization of the Aortic Valve and Aortic Arch in Bicuspid Aortic Valve Patients.

Patients with bicuspid aortic valve (BAV) commonly have associated aortic stenosis and aortopathy. The geometry of the aortic arch and BAV is not well defined quantitatively, which makes clinical classifications subjective or reliant on limited 2D measurements. The goal of this study was to characterize the 3D geometry of the aortic arch and BAV using objective and quantitative techniques. Pre-TAVR computed tomography angiogram (CTA) in patients with BAV and aortic stenosis (AS)were analyzed (n = 59) by assessing valve commissural angle, presence of a fused region, percent of fusion, and calcium volume. The ascending aorta and aortic arch were reconstructed from patient-specific imaging segmentation to generate a centerline and calculate maximum curvature and maximum area change for the ascending aorta and the descending aorta. Aortic valve commissural angle signified a bimodal distribution suggesting tricuspid-like (≤150°, 52.5% of patients) and bicuspid-like (>150°, 47.5%) morphologies. Tricuspid like was further classified by partial (10.2%) or full (42.4%) fusion, and bicuspid like was further classified into valves with fused region (27.1%) or no fused region (20.3%). Qualitatively, the aortic arch was found to have complex patient-specific variations in its 3D shape with some showing extreme diameter changes and kinks. Quantitatively, subgroups were established using maximum curvature threshold of 0.04 and maximum area change of 30% independently for the ascending and descending aorta. These findings provide insight into the geometric structure of the aortic valve and aortic arch in patients presenting with BAV and AS where 3D characterization allows for quantitative classification of these complex anatomic structures.

Doing Well for Those Who Do Well: Surgical Aortic Valve Replacement in Bicuspid Aortic Valve Patients

Doing Well for Those Who Do Well: Surgical Aortic Valve Replacement in Bicuspid Aortic Valve Patients

Progression of the ascending aorta diameter after surgical or transcatheter bicuspid aortic valve replacement.

Ascending aorta (AA) dilatation in patients with bicuspid aortic valve (AV) is related both to genetic and haemodynamic factors. The aim of this study is to compare late progression of AA dilatation in bicuspid AV patients undergoing surgical aortic valve replacement (SAVR) versus transcatheter aortic valve implantation (TAVI). Data of 189 consecutive patients who underwent AV replacement for severe bicuspid AV stenosis were prospectively collected. Patients who underwent SAVR were compared to patients who underwent TAVI. Indication to the procedure was validated by the institutional Heart Team. Aortic diameters were evaluated by transthoracic echocardiogram. Differences between preoperative and long-term follow-up AA diameters were compared in the 2 groups. Between January 2015 and December 2021, 143 (76%) patients underwent SAVR and 46 (24%) patients underwent TAVI. At 4.6 (standard deviation 1.7) years follow-up, patients in the TAVI group showed significantly lower survival (P = 0.00013) and event-free survival (P < 0.0001). AA diameter progression was lower in surgical compared to transcatheter patients, 0.95 (0.60, 1.30) vs 1.65 (0.67, 2.63) mm, P = 0.02. AA diameter progression indexed for body surface area and height was lower in the surgical group: 0.72 (0.38, 1.05) vs 1.05 (0.39, 1.71) mm/m2, P = 0.02, and 0.59 (0.36, 0.81) vs 1.11 (0.44, 1.78) mm/m, P = 0.001, respectively. At multivariable linear regression analysis transcatheter procedure, baseline aortic diameter and paravalvular leak were significantly associated with increased postoperative AA dilatation. Bicuspid AV patients who underwent SAVR, showed significantly less long-term AA diameter progression than patients who underwent transcatheter procedure.