Aortic strain in bicuspid aortic valve: an analysis

Abstract

Introduction: Bicuspid aortic valve (BAV) is frequently related to aortic valve disease and aortopathy and it is usually monitored by transthoracic echocardiography and computed tomography (CT) angiography. However, early markers of disease progression are not currently available. Speckletracking echocardiography (STE) has shown consistent results among other cardiac pathologies. The present study evaluated STE aortic and left ventricle (LV) strain prognostic value, their discriminative power and their correlation with the degree of valvular regurgitation. Methods:We retrospectively followed forty-eight adult patients with BAV and twenty gender and age matched controls for a median period of approximately twenty months, all with LV ejection fraction > 50% and without wall-motion abnormalities or poor acoustic window. We measured LV and aortic classic and STE parameters and we analysed their statistically significant differences, as well as their discriminative power of BAV presence. Hereinafter, we assessed their correlation with the primary cardiac outcome -aortic valve replacement (AVR) -through a COX regression analysis. Finally, our population with BAV was divided according to their severity of aortic regurgitation (AR) in none, mild, moderate or severe, and we evaluated: a) their echocardiographic parameters' differences throughout the disease; and b) which values predicted the existence of at least moderate AR. Results:In our sample, values of LV dimensions and aortic diameter were higher in BAV population.Regarding their mechanics, LV global longitudinal strain (GLS) was impaired (p<0.001) and aortic global circumferential strain (GCS) did not differ among the two groups. Aortic GLS was significantly increased (p=0.027) and was a reliable discriminator of BAV presence, though aortic diameter was better (area under the curve = 0.92). In BAV patients with AR, aortic GCS decreased with the increment of severity (p=0.004) and severe AR had an exponentially augmented aortic GLS (45.2 ± 32.3%). Aortic valve replacement was the only outcome observed and its only predictor was LV end-diastolic volume (indexed).Discussion: BAV patients had impaired LV contraction, despite having preserved LV ejection fraction.Our population had pronounced aortic dilatation, which caused a distortion in strain calculation, with high values of aortic GLS. Increasing severity of AR caused a reduction in aortic GCS, partly reflecting its significant vascular wall impairment throughout the disease.Conclusion: STE aortic strain was not a reliable predictor of surgery in BAV patients.

Myocardial strain of the left ventricle by speckle tracking echocardiography: From physics to clinical practice

“…In addition, Carlos et al 174 . reported a significant reduction in GLS in patients with bicuspid aortic valve (BAV) in comparison to control group (− 16.0 ± 2.8 vs. − 19.0 ± 1.9, p < 0.001), underlining the subclinical alteration in LV mechanics even without valvulopathy or aortopathy.…”

“…172 After aortic valve replacement, LV deformation shows improvement in all the 3 normal directions. 173 In addition, Carlos et al 174 Finally, GLS provides useful information in the setting of mitral stenosis (MS). It was demonstrated how patients affected by MS present significantly lower absolute GLS values compared to healthy control participants prior to percutaneous balloon mitral valvuloplasty.…”

Bicuspid Aortic Valve in Children and Adolescents: A Comprehensive Review

“…In paediatric patients with congenital AS treated with balloon aortic valvuloplasty, post-procedural GLS was lower than in healthy children, with more impaired values in those with LV eccentric hypertrophy or with higher residual aortic gradients [ 35 ]. Carlos et al reported lower GLS values in BAV patients [ 36 ]. Impaired GLS has been observed more frequently in cases of valve dysfunction, with a progressive worsening according to the severity of the valvulopathy, and it has been correlated, even in BAV patients, with the risk of undergoing aortic valve replacement [ 37 ].…”