Stochastic Modelling and Dynamic Analysis of Cardiovascular System with Rotary Left Ventricular Assist Devices

TL;DR

This paper develops a stochastic cardiovascular model with LVAD to analyze the impact of pump power on heart recovery, using generalized polynomial chaos for efficient uncertainty quantification.

Contribution

It introduces a stochastic modeling approach with gPC to assess LVAD effects on cardiovascular dynamics, accounting for patient variability.

Findings

Identified critical LVAD pump power thresholds for heart support.

Demonstrated gPC model's efficiency in uncertainty propagation.

Provided insights into aortic valve dynamics under LVAD support.

Abstract

The left ventricular assist device (LVAD) has been used for end-stage heart failure patients as a therapeutic option. The aortic valve plays a critical role in heart failure and its treatment with LVAD. The cardiovascular-LVAD model is often used to investigate the physiological demands required by patients and predict the hemodynamic of the native heart supported with a LVAD. As a bridge to recovery treatment, it is important to maintain appropriate and active dynamics of the aortic valve and the cardiac output of the native heart, which requires that the LVAD pump must be adjusted so that a proper balance between the blood contributed through the aortic valve and the pump is maintained. In this paper, our objective is to identify a critical value of the pump power to ensure that the LVAD pump does not take over the pumping function in the cardiovascular-pump system and share the ejected blood with left ventricle to help the heart to recover. In addition, hemodynamic often involves variability due to patients heterogeneity and the stochastic nature of cardiovascular system. The variability poses significant challenges to understand dynamic behaviors of the aortic valve and cardiac output. A generalized polynomial chaos (gPC) expansion is used in this work to develop a stochastic cardiovascular-pump model for efficient uncertainty propagation, from which it is possible to rapidly calculate the variance in the aortic valve opening duration and the cardiac output in the presence of variability. The simulation results show that the gPC based cardiovascular-pump model is a reliable platform that can provide useful information to understand the effect of LVAD pump on the hemodynamic of the heart.