Performance optimization of the pulsatile synchronous LVAD based on myocardial energetics and cardiac output using a computer simulation

When myocardial infarction compromises cardiac output, treatment sometimes involves the application of a pulsatile synchronous left ventricular assist device (LVAD). The authors use a computer simulation to explore the possibility of optimal phasing of pump cycle with respect to events in the cardiac cycle from the standpoint of improved myocardial energetics and system flow. Central to the simulation is a time-varying elastance model of the left ventricle. It is coupled to a closed-loop circulatory model that consists of a nonlinear multielement aorta model, the main aortic branches including the coronaries, a lumped venous system model, a time-varying elastance model of the right ventricle, and lumped models of the pulmonary arteries, and veins. Oxygen availability per beat is calculated from the arteriovenous oxygen difference and the total coronary flow and oxygen consumption per beat is computed