In vitro performance of trans‐valve left ventricular assist device installed at aortic valve position

Abstract

In this study, we developed a trans‐valve left ventricular assist device (LVAD) that unites a rear‐impeller axial‐flow blood pump (AFBP) and a polymer membrane valve placed at the aortic valve position. The diameter and length of the rear impeller AFBP was 12 and 63 mm, respectively. The polymer membrane valve was similar to the jelly‐fish valve consisting of a valve leaflet made of silicone rubber (thickness 0.5 mm), valve ring (diameter: 25 mm), and valve spokes. The trans‐valve LVAD was examined in a mock circulation. An implantable pulsatile flow (PF) VAD was connected to an atrial reservoir to simulate the left ventricle (LV), and the Hall valve was worn in the inflow port, and the trans‐valve LVAD was placed in the outflow port as an outflow valve. When the motor rotational speed increased to 26 400 rpm, the mean aortic flow increased from 4.2 to 5.3 L/min, mean aortic pressure increased from 83.4 to 100 mm Hg, and mean motor current of the implantable PF VAD decreased from 1.18 to 0.94 A (unloading effect on LV −21%). The energy equivalent pressure increased from 85.2 to 102 mm Hg, and surplus hemodynamic energy (SHE) decreased by −15.4% from the baseline. In conclusion, the trans‐valve LVAD has an advantage of preserving pulsatility without any complicated mechanism and is a novel and promising LV support device.

Mechanical and interventional support for heart failure with preserved ejection fraction: A review

“…Lower pump operational speeds would correspond to an LVAD being in parallel to the heart. This arrangement can be contrasted to the fixed, obligatory in‐series position of a trans‐aortic valve LVAD 34 which would be the most ineffective of the mechanical support options discussed for RCM and HCM. Operating the pump from the LV in series at higher rotational speeds for patients with HFpEF significantly increase their risk of suction events due to low LV reserves.…”