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Background: Coarctation of the aorta (COA) is associated with reduced aortic distensibility and systemic hypertension (HTN). 60–85% of COA patients have a bicuspid aortic valve (BAV). It is not known if the presence of a BAV accentuates the aortopathy and HTN in CoA patients. We examined whether patients with COA and a BAV had lower aortic distensibility by CMR, and a higher prevalence of systemic HTN compared with COA patients with a tricuspid aortic valve (TAV). Methods: In successfully repaired COA patients excluding those with residual COA, ascending aorta (AAO) and descending aorta (DAO) distensibility was calculated by CMR. HTN was assessed using standard pediatric and adult criteria. Results: Among 215 COA patients (median age 25.3 years), 67% had a BAV, and 33% had a TAV. Median AAO distensibility z-score was lower in the BAV group (− 1.2 versus − 0.7; p = 0.014) but DAO distensibility was similar in BAV and TAV patients. HTN prevalence was similar in BAV (32%) and TAV groups (36%, p = 0.56). On multivariable analysis controlling for confounders, HTN was not associated with BAV but was associated with male gender (p = 0.003) and older age at follow-up (p = 0.004). Conclusions: In young adults with treated COA, those with a BAV had stiffer AAO compared to those with a TAV, but DAO stiffness was similar. HTN was not related to BAV. These results suggest that although the presence of a BAV in COA exacerbates the AAO aortopathy, it does not exacerbate the more generalized vascular dysfunction and associated HTN. [ABSTRACT FROM AUTHOR]

Background: Bicuspid aortic valve (BAV) disease is associated with increased risk of aortopathy. In addition to current intervention guidelines, BAV mediated changes in aortic 3D hemodynamics have been considered as risk stratification measures. We aimed to evaluate the association of 4D flow cardiovascular magnetic resonance (CMR) derived voxel-wise aortic reverse flow with aortic dilation and to investigate the role of aortic valve regurgitation (AR) and stenosis (AS) on reverse flow in systole and diastole. Methods: 510 patients with BAV (52 ± 14 years) and 120 patients with trileaflet aortic valve (TAV) (61 ± 11 years) and mid-ascending aorta diameter (MAAD) > 35 mm who underwent CMR including 4D flow CMR were retrospectively included. An age and sex-matched healthy control cohort (n = 25, 49 ± 12 years) was selected. Voxel-wise reverse flow was calculated in the aorta and quantified by the mean reverse flow in the ascending aorta (AAo) during systole and diastole. Results: BAV patients without AS and AR demonstrated significantly increased systolic and diastolic reverse flow (222% and 13% increases respectively, p < 0.01) compared to healthy controls and also had significantly increased systolic reverse flow compared to TAV patients with aortic dilation (79% increase, p < 0.01). In patients with isolated AR, systolic and diastolic AAo reverse flow increased significantly with AR severity (c = − 83.2 and c = − 205.6, p < 0.001). In patients with isolated AS, AS severity was associated with an increase in both systolic (c = − 253.1, p < 0.001) and diastolic (c = − 87.0, p = 0.02) AAo reverse flow. Right and left/right and non-coronary fusion phenotype showed elevated systolic reverse flow (> 17% increase, p < 0.01). Right and non-coronary fusion phenotype showed decreased diastolic reverse flow (> 27% decrease, p < 0.01). MAAD was an independent predictor of systolic (p < 0.001), but not diastolic, reverse flow (p > 0.1). Conclusion: 4D flow CMR derived reverse flow associated with BAV was successfully captured even in the absence of AR or AS and in comparison to TAV patients with aortic dilation. Diastolic AAo reverse flow increased with AR severity while AS severity strongly correlated with increased systolic reverse flow in the AAo. Additionally, increasing MAAD was independently associated with increasing systolic AAo reverse flow. Thus, systolic AAo reverse flow may be a valuable metric for evaluating disease severity in future longitudinal outcome studies. [ABSTRACT FROM AUTHOR]

Background: Coarctation of aorta (CoA) may progressively develop aortic dilation at other site of the aorta and can lead to fatal aortic diseases. We aimed to evaluate the occurrence of aortic dilation and related predictors in patients with CoA using dual-source computed tomography (DSCT).Methods: Fifty-three patients with CoA identified by DSCT were retrospectively reviewed. Aortic diameters were measured at six different levels and standardized as z-scores based on the square root of body surface area. Coarctation site-diaphragm ratio (CDR) was used to describe the degree of narrowing. A total of 26 patients were included in mild group (CDR > 50%) and 27 in severe group (CDR < 50%) according to the severity of coarctation. Student's t-test and Spearman correlation coefficients, univariate and multivariable logistic regression analyses were used to assess the risk factors including age, degree of narrowing and other malformations for aortic dilation.Results: Severe group had significantly larger z-scores of ascending aorta (2.41 ± 0.39 vs. 2.10 ± 0.57, p < 0.05) and post-coarctation aorta (2.17 ± 0.48 vs. 1.68 ± 0.43, p < 0.001) compared with mild group. Degree of coarctation was associated with the z-scores of the ascending aorta (r = - 0.356, p < 0.05) and post-coarctation aorta (r = - 0.414, p < 0.05). Collateral circulation was related to the z-scores of ascending aorta (r = 0.375, p < 0.05). Increased severity of coarctation was independent predictor of ascending (odds ratio 7.46; 95% CI 1.19-46.76; p < 0.05) and post-coarctation aortic dilation(odds ratio 8.42; 95% CI 1.84-38.56; p < 0.05).Conclusions: Ascending and post-coarctation aortic diameters or dilations were both associated with the degree of coarctation. By comprehensively evaluating the aortic diameters and associated malformations including collateral circulation, DSCT can aid in stratification of risk for aortic dilation in patients with CoA. [ABSTRACT FROM AUTHOR]

Background: We aimed to determine the circulating miRNA expression profile associated with BAV and aortic dilation to provide diagnostic and prognostic biomarkers for BAV and/or aortic dilation.Methods and Results: We applied a miRNome-wide microarray approach using plasma samples (n = 24) from healthy tricuspid aortic valve individuals, BAV patients and BAV patients with aortic dilation to compare and identify the specific miRNAs associated with BAV and aortic dilation. In a second stage, the expression patterns of the miRNA candidates were validated by RT-qPCR in an independent cohort (n = 43). The miRNA microarray data and RT-qPCR analyses revealed that the expression levels of circulating miR-122, miR-130a and miR-486 are significantly influenced by the morphology of the aortic valve (bicuspid/tricuspid) and could be functionally involved in the regulation of TGF-β1 signalling. Furthermore, the expression pattern of miR-718 in the plasma was strongly influenced by dilation of the ascending aorta. miR-718 expression was inversely correlated with the aortic diameter (R = -0.63, p = 3.1 × 10-5) and was an independent predictor of aortic dilation (β = -0.41, p = 0.022). The genes targeted by miR-718 are involved in the regulation of vascular remodelling.Conclusions: We propose that miR-122, miR-130a, miR-486 and miR-718 are new molecular features associated with BAV and aortic dilation principally by the activation of TGF-β1 pathway and vascular remodelling mediated by VEGF signalling pathways. [ABSTRACT FROM AUTHOR]