Observation and Quantification of Cavitation on a Mechanical Heart Valve with an Electro-Hydraulic Total Artificial Heart

Abstract

In previous studies, we investigated the cavitation phenomenon in a mechanical heart valve using an electro-hydraulic total artificial heart. With this system, a 50% glycerin solution kept at 37°C was used as the working fluid. We reported that most of the cavitation bubbles were observed near the valve stop and were caused by the squeeze flow. However, in these studies, the effect of the partial pressure of CO₂ on the mechanical heart valve cavitation was neglected. In this study, in order to investigate the effect of the partial pressure of CO₂ on mechanical heart valve cavitation using an electro-hydraulic total artificial heart, we controlled the partial pressure of the CO₂ in vitro. A 25-mm Medtronic Hall valve was installed in the mitral position of an electro-hydraulic total artificial heart. In order to quantify the mechanical heart valve cavitation, we used a high-speed camera. Even though cavitation intensity slightly increased with increases in the PCO₂ at heart rates of 60, 70 and 100 bpm, throughout the experiment, there was no significant difference between the PCO₂ and cavitation intensity.