Mechano-electric coupling simulation of left ventricle: effect of excitation propagation pattern on contractile behavior

Abstract

The left ventricle (LV) plays an important role in pumping blood throughout the body. The LV motion is attributed to an electrophysiological mechanism, i.e. cardiac conduction system and excitation propagation, and mechanical mechanisms, i.e. contraction of the cardiac muscle fibers. In a sinus rhythm, the excitation propagates through the LV due to the electrophysiological stimulus of the heart muscle cells with a constant rhythm. However, in an arrhythmia, the stimulus rhythm becomes inconstant, and some arrhythmia with a severe abnormality results in a reduction of cardiac function. So far, although some computational studies considering the electrophysiological change during arrhythmia have been done, little is known about the effect of coupling mechanism between electrophysiological dynamics and the entire LV kinematic behavior. In this study, an electrophysiological-mechanical integrated LV model is developed, and the effects of the excitation propagations in both the normal and arrhythmia conditions on the LV kinematics are investigated.