Computational Models and Methods for Cardiac Dynamics

Atrial fibrillation is an abnormal rhythm originating in the upper chambers of the heart afflicting 2-3 million people in the US alone and whose incidence rises with increasing age. Due to the "graying of our population", an estimated 12-16 million Americans will be affected by 2050. Not only is its incidence of epidemic proportions, its morbidity is also significant because of its association with increased risk of both thromboembolism and stroke. The heartbeat under normal conditions is initiated by an electrical impulse that propagates diffusively through the heart and elevates the voltage at each cell, producing an action potential. The electrical waves that propagate, without damping, through the heart can exhibit complex dynamics and instabilities such as period-doubling bifurcations, alternans, two-dimensional spiral waves, three-dimensional scroll waves, and spatiotemporal turbulence (fibrillation) that can compromise the heart's ability to contract and pump blood efficiently. In this talk I will present an overview of my research in this field.