電気油圧駆動式全人工心臓の開発: 血液ポンプ駆動ユニットの改良

摘要

An electrohydraulic total artificial heart (EHTAH) system has been developed. The EHTAH system consists of diaphragm-type blood pumps, an electrohydraulic actuator, an internal control unit, a transcutaneous energy transfer system (TETS), a transcutaneous optical telemetry system (TOTS), and an internal battery. The reciprocating rotation of the impeller generates oil pressure which drives the blood pumps at alternating intervals. The blood pumps and the actuator were successfully integrated into the pump unit without oil conduits. As a result of miniaturizing the blood pumps and the actuator, the displacement volume and weight of the EHTAH system decreased to 872 ml and 2492g, respectively. Furthermore, the maximum flow rate and efficiency increased up to 12 L/min and 15.4%. The pump units and the EHTAH systems were successfully implanted in 36 calves weighing from 55 to 87kg. In the longest case, the calf with the pump unit survived for 87 days and the calf with the EHTAH system survived for 70 days. The EHTAH system was powered by the TETS, and was powered everyday by the internal battery for 40 minutes. These results indicate that the EHTAH system has the potential to become a fully implantable cardiac replacement system.%米国では全ての装置を体内へ埋め込む完全埋め込み型全rn置換型人工心臓AbioCor IRHの臨床治験が実施され，2001rn年から2004年までに14例の埋め込みが行われた。また血rn液ポンプのみを体内へ埋め込み，駆動装置を体外に設置すrnる全置換型人工心臓CardioWest TAHは現在までに全世rn界で300例以上の埋め込みが行われている。