Abdominally-Placed Implantable Left Ventricular Assist System (LVAS) with a Continuous Monitoring System

Abstract

A ventricular assist system (VAS) for temporary use was developed at the National Cardiovascular Center, Japan, and it has been used in more than 100 clinical cases [1]. In 1990, the Japanese government approved this VAS for commercial release. Some of the patients, however, could not be weaned from the VAS because of severe cardiac damage. A bridge to cardiac transplantation or permanent assist is an alternative option for these patients [2–3]. We developed an implantable left VAS (LVAS) to improve the quality of life in these patients. This new LVAS consists of an abdominally-placed implantable diaphragm-type blood pump, a continuous monitoring and control system, using the impedance method with an automatic calibration mechanism, and a portable control drive unit (CDU). Here we present this LVAS and the initial results of chronic animal experiments.