小児用人工心臓用アキシャル型セルフベアリングモータの動特性評価

抄録

Mechanical circulatory support devices such as ventricular assist devices (VADs) are required for treatment of heart failure patients with small body size. However, clinically available rotary VADs which can be implanted in small pediatric patients still have not been developed. The implantable pediatric rotary VADs require compact device size, high mechanical durability and blood biocompatibility. Selection of impeller suspension methods is significant important for development of the rotary VADs. Magnetic suspension system is one of the strongest candidates to develop next generation VADs which can completely suspend a spinning rotor impeller without mechanical contact. Our research group has been developed an ultra-compact double stator self-bearing motor with 5-degrees of freedom (-DOF) control. The 5-DOF controlled self-bearing motor is 22 mm in diameter and 34 mm in height. This paper investigated magnetic suspension stability during pump operation. The developed maglev centrifugal blood pump produced flow rate of 0-3 L/min against head pressure of 60-100 mmHg at rotating speeds of 4000-5000 rpm. The centrifugal impeller was completely suspended with the proposed 5-DOF control concept. The results indicate sufficient pump performance for pediatric circulatory support and stable impeller suspension performance.