Events Calendar

4D Blood Flow in the Human Heart: Optimal Vortex Ring Formation and Validation Challenges

Speaker: Johannes Töger, Lund University

Talk Title: 4D Blood Flow in the Human Heart: Optimal Vortex Ring Formation and Validation Challenges

Series: Medical Imaging Seminar Series

Abstract: Diastolic dysfunction, i.e. dysfunction of the filling mechanisms of the left ventricle (LV) of the heart, is a disease with poor prognosis even in its mild form [1] and new measures of diastolic dysfunction may improve patient care. During the early phase of diastole (filling) of the human heart, a vortex ring forms in the left ventricle (LV) downstream from the mitral valve [2, 3]. Features of the vortex ring has been shown to reflect overall cardiac function [3, 4] and may therefore give new insights into the pathophysiology of diastole.

The full three-dimensional dynamics of the vortex ring can be imaged using 4D flow magnetic resonance imaging and mathematical post-processing by Lagrangian Coherent Structures (LCS), a flow analysis tool based on the theory of nonlinear dynamical systems (Figure 1). Furthermore, we have constructed a flow phantom for validation of 4D flow measurements of pulsatile flow (Figure 2) using particle imaging velocimetry (PIV) and planar laser-induced fluorescence (PLIF), meeting the formidable design challenge of producing a pulsatile, physiological, fully three-dimensional and highly repeatable experiment [5].

In vivo studies, healthy volunteers (n=23) and patients with heart failure (n=23) [6, 7] show that the healthy heart displays a matching between the volume of the vortex ring and the volume of the LV that is lost in heart failure. Furthermore, the mixing of blood in the vortex ring is increased in heart failure patients compared to healthy hearts, which may reflect the impaired diastolic function in the patients.

Host: Prof. Krishna Nayak

Location: Hughes Aircraft Electrical Engineering Center (EEB) - 132

Audiences: Everyone Is Invited

Contact: Talyia White