Comparison of Immersed Boundary Simulations of Heart Valve Hemodynamics Against In Vitro 4D Flow MRI Data

Alexander D Kaiser; Nicole K Schiavone; Christopher J Elkins; Doff B McElhinney; John K Eaton; Alison L Marsden

doi:10.1007/s10439-023-03266-2

Comparison of Immersed Boundary Simulations of Heart Valve Hemodynamics Against In Vitro 4D Flow MRI Data

Ann Biomed Eng. 2023 Oct;51(10):2267-2288. doi: 10.1007/s10439-023-03266-2. Epub 2023 Jun 28.

Authors

Alexander D Kaiser^#^{1

2}, Nicole K Schiavone^#³, Christopher J Elkins³, Doff B McElhinney^{1

2

4}, John K Eaton³, Alison L Marsden^{5

6

7

8

9}

Affiliations

¹ Department of Pediatrics (Cardiology), Stanford University, Stanford, CA, USA.
² Stanford Cardiovascular Institute, Stanford, CA, USA.
³ Department of Mechanical Engineering, Stanford University, Stanford, CA, USA.
⁴ Department of Cardiothoracic Surgery, Stanford University, Stanford, CA, USA.
⁵ Department of Pediatrics (Cardiology), Stanford University, Stanford, CA, USA. amarsden@stanford.edu.
⁶ Stanford Cardiovascular Institute, Stanford, CA, USA. amarsden@stanford.edu.
⁷ Department of Mechanical Engineering, Stanford University, Stanford, CA, USA. amarsden@stanford.edu.
⁸ Institute for Computational and Mathematical Engineering, Stanford University, Stanford, CA, USA. amarsden@stanford.edu.
⁹ Department of Bioengineering, Stanford University, Stanford, CA, USA. amarsden@stanford.edu.

^# Contributed equally.

Abstract

The immersed boundary (IB) method is a mathematical framework for fluid-structure interaction problems (FSI) that was originally developed to simulate flows around heart valves. Direct comparison of FSI simulations around heart valves against experimental data is challenging, however, due to the difficulty of performing robust and effective simulations, the complications of modeling a specific physical experiment, and the need to acquire experimental data that is directly comparable to simulation data. Such comparators are a necessary precursor for further formal validation studies of FSI simulations involving heart valves. In this work, we performed physical experiments of flow through a pulmonary valve in an in vitro pulse duplicator, and measured the corresponding velocity field using 4D flow MRI (4-dimensional flow magnetic resonance imaging). We constructed a computer model of this pulmonary artery setup, including modeling valve geometry and material properties via a technique called design-based elasticity, and simulated flow through it with the IB method. The simulated flow fields showed excellent qualitative agreement with experiments, excellent agreement on integral metrics, and reasonable relative error in the entire flow domain and on slices of interest. These results illustrate how to construct a computational model of a physical experiment for use as a comparator.

Keywords: Heart valve fluid–structure interaction; Heart valve simulation; Immersed boundary method; Immersed boundary method validation; Pulmonary valve modeling.

MeSH terms

Aortic Valve
Computer Simulation
Heart Rate
Heart Valves / diagnostic imaging
Hemodynamics*
Magnetic Resonance Imaging
Models, Cardiovascular*

Abstract

MeSH terms

Grants and funding