Andres Caballero

Biomedical Engineering PhD Thesis Defense

Date: Wednesday, October 23, 2019

Time: 11:30 am

Location: Room 104, Technology Enterprise Park (TEP)

Advisor:

Wei Sun, PhD

Committee Members:

Rudolph Gleason, PhD

Cyrus Aidun, PhD

Stamatios Lerakis, MD, PhD

John Oshinski, PhD

Title: Computational Modeling of Left Ventricle-Valve Dynamics using a Fluid-Structure Interaction Framework.

Abstract:

The left heart (LH) is a key player of the cardiovascular system. Diseases of and associated with the left ventricle (LV)-valve complex account for a large share of cardiovascular disease-related deaths. As accurate and detailed interrogation of cardiac function has been actively pursued clinically in recent years, computational modeling has emerged as a viable approach to study the LH dynamics in physiologic and pathologic states. Yet, most of the previous computational investigations have either solved the fluid or structural physics alone, have been limited to idealized geometries, have adopted linear elastic material models, have focused on a short time frame of the cardiac cycle, or have not incorporated all LH structures. Proper LV-valve dynamics requires a balanced interplay between the LV, the left atrium (LA), the aortic valve (AV), the mitral valve (MV) and the blood flow. Thus, blood-leaflet interaction, leaflet coaptation, and flow dynamics into, within and outward of the LV are all critical parameters to investigate; an area where fluid-structure interaction (FSI) modeling is required.

The main objective of this work was to model the FSI between the blood flow, the heart valves and the cardiac wall throughout the cardiac cycle in order to improve our understanding of the biomechanics of the LH complex under baseline, diseased and repaired states. First, a novel FSI framework for modeling subject-specific and patient-specific LV-valve dynamics was developed and validated. Next, these holistic LH models were used to better understand the biomechanical challenges facing various minimally-invasive AV replacement and MV repair procedures.