Abstract：
:A bicuspid aortic valve (BAV) is a congenital cardiac disorder where the valve consists of only two cusps instead of three, as in a normal tricuspid valve (TAV). Although 97 % of BAVs include asymmetric cusps, little or no prior studies have investigated the blood flow through a three-dimensional BAV and root. The aim of the present study was to characterize the effect of asymmetric BAV on the blood flow using fully coupled fluid-structure interaction (FSI) models with improved boundary conditions and tissue properties. This study presents four FSI models, including a native TAV, asymmetric BAVs with or without a raphe, and an almost symmetric BAV. Cusp tissue is composed of hyperelastic finite elements with collagen fibres embedded in the elastin matrix. A full cardiac cycle is simulated by imposing the same physiological blood pressures for all the TAV and BAV models. The latter have significantly smaller opening areas compared with the TAV. Larger stress values were found in the cusps of BAVs with fused cusps, at both the systolic and diastolic phases. The asymmetric geometry caused asymmetric vortices and much larger flow shear stress on the cusps which could be a potential initiator for early valvular calcification of BAVs.
journal_name
Med Biol Eng Computjournal_title
Medical & biological engineering & computingauthors
Marom G,Kim HS,Rosenfeld M,Raanani E,Haj-Ali Rdoi
10.1007/s11517-013-1055-4subject
Has Abstractpub_date
2013-08-01 00:00:00pages
839-48issue
8eissn
0140-0118issn
1741-0444journal_volume
51pub_type
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