Seminar Abstract

“Investigating Ventricular Tachycardia as a Result of Premature Stimuli in a Three-Dimensional Canine Cardiac Model of Heart Failure”

Experiments by Akar and Rosenbaum (2003) demonstrated increased arrhythmia vulnerability in canines induced to exhibit the characteristics of heart failure. In these hearts, the delivery of a single premature stimulus caused a conduction block at the subepicardial-midmyocardial cell interface, along the transmural wall of the heart. This was attributed to action potential duration (APD) prolongation in failing hearts, which is markedly heterogeneous across the transmural wall, and was characterized by disproportionate APD prolongation of midmyocardial cells. This subsequently led to the genesis of polymorphic ventricular tachycardia (PVT).

This project aims to replicate these experimental results in a three-dimensional wedge model of the failing canine heart. The wedge is built from diffusion tensor magnetic resonance imaging (DTMRI) data, experimental measurements of conduction velocity and connexin43 expression in failing and non-failing hearts, and utilizes the Greenstein-Winslow single-cell cardiac model.