VentrAssist left ventricular assist systems long-term in vitro reliability

Left ventricular assist systems (LVADs) are typically tested for long-term reliability by using a simulated human cardiovascular system. In this study, 13VentrAssist (Ventracor Ltd, Chatswood, NSW, Australia)systems are tested in mock loops with the aim of demonstrating in vitro continuous operational reliability of the pump subsystem greater than 80% (60%confidence) over 1 year. As of July 9, 2007, the total time on test of all 13 mock loop pumps is 29.36 years. In vitro reliability of the VentrAssist LVAD blood pump is 96.7%(60% confidence) at 1 year. No failures have been seen over 4.5 years of test, and testing is ongoing.