The Impact of Hemopump on Ventricular Energetic Parameters When Mechanical Ventilation is Applied: Numerical Simulation

The aim of this work is to study the impact of left ventricular assist device (LVAD) like Hemopump, on energetic parameters, when mechanical ventilation of the lungs is applied. In order to investigate this interaction, a model of the Hemopump was added, in series to the left ventricle, to a numerical simulator of the circulation. The simulator was implemented using lumped parameters models to reproduce the circulatory phenomena in terms of pressure and volume relationships. For each ventricle variable elastance models reproduce the Starling's law of the heart. In this study the ischemic heart disease was reproduced and subsequently left ventricular assist device was applied. The rotational speed of the Hemopump was changed in steps and was assumed to be constant during each step. The influence of mechanical ventilation was introduced by positive mean thoracic pressure. Positive thoracic pressure and different rotational speed of the LVAD have a significant influence on ventricular energetic variables (such as left and right external work, pressure volume area and cardiac mechanical efficiency).