Abstract
Thrombus formation at the interface between left ventricular wall and the inflow cannula of left ventricular assist device (LVAD) remains to be an unsolved problem that induces complications in clinical practice. The aim of this study is to develop an in vitro airless circuit which produces flow and pressure environments in patients with a LVAD, and to investigate an influence of MPC coating of the inflow cannula of EVAHEART^[○!R] LVAD (Sun Medical Technology Research Co., Japan) on thrombus detachment from the inflow cannula. In the thrombogenicity test, two identical circuits except for the cannula were prepared to form a comparative study. Heparinized blood from a single porcine with activated clotting time ranged within 130-210 sec was circulated for 4.5 hours. The tests were performed under the combinations of the total flow rate of 4 L/min or 5 L/min, and the pump rotational speed of 1800, 1900 or 2000 rpm, respectively. It was elucidated that higher amount of thrombus formed on the MPC non-coated cannula compared with MPC coated cannula. However, there was no difference in the amount of thrombus detached between the two cannula (Student's t-test, p=0.91). From these results, it was elucidated that the MPC non-coated cannula yielded significantly lower proportion of thrombus detachment to thrombus formation than the MPC coated cannula (Student's t-test, p<0.05).
