Effect of left-right heart during biventricular assist device support by speed synchronization: A computer study

Abstract

Biventricular assist device (BiVAD) is a treatment for the end-stage heart failure patients. Normally, after left ventricular assist device (LVAD) implanted in the end-stage heart failure patients, a right heart failure immediately appeared. Then, the right ventricular assist device (LVAD) was implanted. Both LVAD and RVAD implanted so call BiVAD. Additionally, the speed synchronization is a novel concept for remaining the high preload and increasing the cardiac output. It is a potential to promote a bridge to recovery treatment. The cardiovascular, RVAD, LVAD and speed synchronization models (co-pulse mode) are implemented using MATLAB. The normal heart and pathology heart are used in this study. The pathology level of the heart was regulated by a level of maximum elastance (Emax: 30% of normal heart value) in the heart model. The constant speed mode and co-pulse mode (increasing pump speed in systolic period between 8,000–11,000 rpm) are simulated using the MicroMed-DeBakey VAD model. The hemodynamics, ejection fraction, pressure-volume loop and pressure volume area (PVA) of different heart condition and pump mode are simulated. The results indicated the aortic pressure, pulmonary artery pressure and ejection fraction in co-pulse mode are similar to the constant speed mode. However, PVA in co-pulse mode are higher than the constant speed mode on pathology heart. In conclusion, this computer simulation can re-generated the effect of BiVAD under the pathological condition. The optimal ratio of RVAD support is important to prevent the suction event. Speed synchronization can maintain the high PVA than constant speed. Therefore, partial support with co-pulse mode can potentially use for the bridge to recovery treatment.