September 8, 2017Open Access

Fully-coupled fluid-structure interaction simulation of the aortic and mitral valves in a realistic 3D left ventricle model

Q: What is the clinical evidence from this study?

Study design: Other. Population: Normal left ventricular function (n=1). Intervention: Fully-coupled fluid-structure interaction (FSI) simulation (LV-Valve model) vs. LV model without valves (LV-NoValve model). Primary outcome: Peak systolic velocity (m/s).

Key Result

The fully-coupled fluid-structure interaction model with valves predicted a peak systolic velocity of 2.56 m/s, compared to 1.16 m/s in the model without valves and 2.17 m/s from Doppler echo data.

PICO

Population

Normal left ventricular function (n=1)

Intervention / Comparator

Fully-coupled fluid-structure interaction (FSI) simulation (LV-Valve model) vs LV model without valves (LV-NoValve model)

Primary Outcome

Peak systolic velocity (m/s)

Main Result

Absolute Event Rate: 2.56% vs 1.16%

Limitations

The mitral valve geometry was adapted from a previous study due to imaging artifacts in the subject-specific MSCT scans.
Aortic valve calcification was not incorporated in order to mimic a healthy state.
Absence of calcifications at the mitral annulus in the adapted model led to differences in diastolic parameters compared to clinical observations.
Numerical artifacts caused spike values in stress and pressure measurements during valve closure and early systole.

Abstract

In this study, we present a fully-coupled fluid-structure interaction (FSI) framework that combines smoothed particle hydrodynamics (SPH) and nonlinear finite element (FE) method to investigate the coupled aortic and mitral valves structural response and the bulk intraventricular hemodynamics in a realistic left ventricle (LV) model during the entire cardiac cycle. The FSI model incorporates valve structures that consider native asymmetric leaflet geometries, anisotropic hyperelastic material models and human material properties. Comparison of FSI results with subject-specific echocardiography data demonstrates that the SPH-FE approach is able to quantitatively predict the opening and closing times of the valves, the mitral leaflet opening and closing angles, and the large-scale intraventricular flow phenomena with a reasonable agreement. Moreover, comparison of FSI results with a LV model without valves reveals substantial differences in the flow field. Peak systolic velocities obtained from the FSI model and the LV model without valves are 2.56 m/s and 1.16 m/s, respectively, compared to the Doppler echo data of 2.17 m/s. The proposed SPH-FE FSI framework represents a further step towards modeling patient-specific coupled LV-valve dynamics, and has the potential to improve our understanding of cardiovascular physiology and to support professionals in clinical decision-making.

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Cite This Study

Mao et al. (Fri,) conducted a other in Normal left ventricular function (n=1). Fully-coupled fluid-structure interaction (FSI) simulation (LV-Valve model) vs. LV model without valves (LV-NoValve model) was evaluated on Peak systolic velocity (m/s). The fully-coupled fluid-structure interaction model with valves predicted a peak systolic velocity of 2.56 m/s, compared to 1.16 m/s in the model without valves and 2.17 m/s from Doppler echo data.

synapsesocial.com/papers/6a153e76b03a896dfa81ff48 https://doi.org/https://doi.org/10.1371/journal.pone.0184729