Improvement of the Hydrodynamic Response of a Ventricular Assist Device: A False Auricle Solution

Abstract

We propose a new design of the auricular cannula in ventricular assist devices (VADs), consisting of a collapsible large cannula with a capacity approximately equal to the ejection volume of the VAD. The device works as a false auricle and filters the negative pressure that occurs during diastole. We show that the use of this type of cannula improves the hydrodynamic efficiency and the stability of the working conditions. Moreover, during chronic implantation in sheep, hemolysis stays well below pathological levels. These improvements result in much better controllability of the whole VAD.

Development and Clinical Assay of the BCM Ventricular Assist Device

“…The inflow and outflow cannulae have different diameters (29 and 21 mm, respectively) in their junction with the VAD. We used St. Jude Medical valves (1).…”

“…In this way, the systolic period is used for filling of the inflow cannula. This causes a significant increase in the efficiency of the VAD at high frequencies (1,2).…”

Low‐Cost Pulsatile Cardiac Assist Device With Compliant Input Chamber

“…In some cases, this leads to the collapse of the chamber. Some years ago, our group reported that a compliant cannula acting as a false auricle could improve filling of the pump by filtering the negative pressure and unloading the ventricle or auricle during the VAD systole, even if both systoles are synchronized (7,8).…”