Hemodynamic Effects of Concentric and Eccentric Outflow Graft of LVADs on the Aortic Valve

Abstract Background: Aortic valve disease is a common complication of left ventricular assist device (LVAD) support. Optimizing the outflow graft anastomotic type of LVADs might be an alternative that can reduce this complication. However, the effect of this type of LVAD on the biomechanical states of the aortic valve remains unclear.Methods: In this study, a finite element-smoothed particle hydrodynamics-coupled model was established. Two kinds of anastomotic types (concentric and eccentric graft cases) were designed.Results: The anastomotic type could significantly affect the biomechanical states of the aortic valve. During the opening phase, the motion, deformation, and biomechanical states of the leaflet in both cases were similar to each other. The axial hemodynamic force (AHF) imposed on the leaflet in the eccentric graft case (0.9 N) was slightly larger than that in the concentric graft case (0.3 N). During the closing phase, the rapid closing time of the leaflet in the eccentric graft case (40 ms) was longer than that in the concentric graft case (15 ms). In addition, the peak value of the AHF in the concentric graft case was much larger (13 N) than that in the eccentric graft case (4.5 N). The oscillation of the AHF was observed only in the concentric graft case.Conclusions: The eccentric graft could lead to better biomechanical and hemodynamic states of the aortic valve than the concentric graft.