title: A nonpulsatile total artificial heart with 1/R control.
abstract: A total artificial heart (TAH) using continuous flow pumps is promising for size reduction of the device; however, the role of pulsatility in TAHs has been a subject of great debate. Additionally, it is unclear whether, in a nonpulsatile TAH, a physiological control method such as 1/R control can keep the experimental animal in good condition. To realize a nonpulsatile TAH with 1/R control, the artificial valves were removed from undulation pump total artificial hearts (UPTAHs), which can produce both pulsatile and nonpulsatile flows using a single device. The UPTAHs were implanted into 18 goats, and 4 goats survived for more than 1 month. Three weeks of long-term nonpulsatile TAH operation could be tested in the goat that survived for 72 days, and it was proved that 1/R control is possible not only with a pulsatile TAH but also with a nonpulsatile TAH. The general condition of the goat and its organ function did not change on the application of nonpulsatile mode. Cardiac output and arterial pressure changed with the condition of the goat in pulsatile and also in nonpulsatile modes, and the changes seemed almost identical. However, the sucking effect of the atria was very significant in nonpulsatile mode, resulting in hemolysis. Therefore, nonpulsatile TAHs under 1/R control are considered to be inadequate unless some pulsatility can be introduced to avoid fatal sucking effects and to ensure sufficient inflow. During nonpulsatile operation, regular fluctuations were sometimes found in the aortic pressure, and these were caused by the periodic sucking effect in the left atrium that was possibly influenced by respiratory changes.
authors.affiliation: Department of Biomedical Engineering, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan. abe@bme.rcast.u-tokyo.ac.jp
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Abe
authors.forename: Itsuro
authors.initials: I
authors.lastname: Saito
authors.forename: Takashi
authors.initials: T
authors.lastname: Isoyama
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Miura
authors.forename: Wei
authors.initials: W
authors.lastname: Shi
authors.forename: Sachiko
authors.initials: S
authors.lastname: Yamaguchi
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Inoue
authors.forename: Hidemoto
authors.initials: H
authors.lastname: Nakagawa
authors.forename: Minoru
authors.initials: M
authors.lastname: Ono
authors.forename: Ayumi
authors.initials: A
authors.lastname: Kishi
authors.forename: Toshiya
authors.initials: T
authors.lastname: Ono
authors.forename: Akimasa
authors.initials: A
authors.lastname: Kouno
authors.forename: Tsuneo
authors.initials: T
authors.lastname: Chinzei
authors.forename: Kou
authors.initials: K
authors.lastname: Imachi
mesh_terms: D000818:Animals; D001772:Blood Cell Count; D002302:Cardiac Output; D005260:Female; D006041:Goats; D006354:Heart, Artificial; D011673:Pulsatile Flow