Collagen Bundle Orientation Explains Aortic Valve Leaflet Coaptation
نویسندگان
چکیده
The aortic valve owes its strength and durability to a network of collagen fibers within the leaflets. However, the pattern of these fibers and their role in valve function is not well understood. We imaged and quantified the macroscopically visible pattern of collagen fibers in seven porcine aortic valves with particular attention to measuring this pattern in the unstrained leaflet. We then used a structural finite element model of the aortic valve to study the effect of the observed collagen pattern on the configuration of the loaded valve. Results showed that collagen is oriented oblique to the free edge over much of the leaflet in its unstrained state, and simulations suggest that this architecture plays an important role by enabling adequate valve leaflet coaptation. Simulation results were validated by comparison with images of a porcine aortic valve under load.
منابع مشابه
Straightening of curved pattern of collagen fibers under load controls aortic valve shape.
The network of collagen fibers in the aortic valve leaflet is believed to play an important role in the strength and durability of the valve. However, in addition to its stress-bearing role, such a fiber network has the potential to produce functionally important shape changes in the closed valve under pressure load. We measured the average pattern of the collagen network in porcine aortic valv...
متن کاملA Fluid Structure Interaction Model of Native Aortic Valve with Physiologic Blood Pressure and Tissue Properties
The kinematics and dynamics of the aortic valve (AV) are highly dependent on the combined mechanical properties of the valve and the aortic root (AR), as well as the blood flow. Previous numerical models of physiological AV and AR, that included coaptation under the full cardiac cycle, ignored the influence of the blood flow (performing “dry” simulations). This study presents a full fluid-struc...
متن کاملLower Transient Stresses in an Aortic Valve Leaflet with Oblique Reinforcement Fibers: a Finite Element Study
INTRODUCTION Native aortic valve leaflets contain a network of strong collagen fibers within a matrix of relatively distensible tissue. This composite structure leads to anisotropic mechanical properties and is believed to play an important role in the ability of the structure to withstand the stresses of cyclic loading over billions of heart beats. Replacement valves that consist of animal tis...
متن کاملComplex Collagen Fiber and Membrane Morphologies of the Whole Porcine Aortic Valve
OBJECTIVES Replacement aortic valves endeavor to mimic native valve function at the organ, tissue, and in the case of bioprosthetic valves, the cellular levels. There is a wealth of information about valve macro and micro structure; however, there presently is limited information on the morphology of the whole valve fiber architecture. The objective of this study was to provide qualitative and ...
متن کاملPatient-specific simulation of a stentless aortic valve implant: the impact of fibres on leaflet performance.
In some cases of aortic valve leaflet disease, the implant of a stentless biological prosthesis represents an excellent option for aortic valve replacement (AVR). In particular, if compared with the implant of mechanical valves, it provides a more physiological haemodynamic performance and a reduced thrombogeneticity, avoiding the use of anticoagulants. The clinical outcomes of AVR are strongly...
متن کامل