Mitral regurgitation and axial flow left ventricular assist device: a computer simulation study.

Good right ventricular function is one of the major determinants of long-term outcomes in patients with implanted left ventricular assist devices (LVADs). In the present study, a computer model was developed to assess the impact of mitral regurgitation on right ventricular workload at different levels of LVAD support. Left ventricular assist device was simulated by a model of HeartMate II. The computer model has shown that the regurgitant volume of the mitral valve falls significantly only after the systolic pressure in the left ventricle decreases, which occurs at higher LVAD revolutions per minute (RPM) when there is no ejection through the aortic valve. However, at low LVAD RPM, the pressures in the left atrium and the pulmonary artery decrease significantly, despite a small decrease in regurgitant volume. According to the computer model, LVAD support decreases mitral regurgitation. Furthermore, regurgitant volume has a smaller impact on the right ventricular afterload when compared with a heart without LVAD support.