APPROPRIATE DRIVE CONTROL OF VARIOUS LEFT VENTRICULAR ASSIST SYSTEMS

Abstract

We evaluated drive-modes and parameters of Zeon and Novacor left ventricular assist systems (LVAS) for appropriate drive-control in the short-term and long-term after operation. In control of the Zeon LVAS, pump ejection in the early diastole of the native heart with an intra-aortic balloon support in the late diastole was effective for cardiac recovery from postcardiotomy heart failure. Of 5 patients with the Zeon LVAS, 3 were weaned from the LVAS and 2 were discharged from the hospital. In the drive-control of the Novacor LVAS, specific setting of of the fill rate trigger mode as a counter-ejection was most appropriate for reduction of cardiac pre-and after-load and stable cardiac output. During 6 months after the Novacor implantation, gradual recovery of the native left ventricle was confirmed by means of echocardiography. However, the ventricular recovery did not reached the level of weaning from the Novacor LVAS. The patient underwent orthotopic heart transplantation after 7 months of the Novacor LVAS bridge, and he has survived with excellent general condition for over 1 year