title: Concept of left atrial pressure estimation using its pulsatile amplitude in the helical flow total artificial heart.
abstract: The total artificial heart (TAH) requires physiological control to respond to the metabolic demand of the body. To date, 1/R control is a single physiological control method that can control venous pressure. To realize an implantable 1/R control system, we are developing a new pressure measuring method using absolute pressure sensor. To find a method for absolute pressure sensor, which went well without calibration, concept of left atrial pressure (LAP) estimation using its pulsatile amplitude was proposed. Its possibility was investigated with two long-term survived goats whose hearts were replaced with the helical flow TAHs. In manual control condition, there existed a positive relation between mean LAP (mLAP) and normalized pulsatile amplitude (NPA). Percent systole revealed not to affect the relationship between mLAP and NPA. Dispersion was observed between different pulse rates. As for cardiac output difference (QLD) that is the difference of flow rate between systolic and diastolic phases, similar results were obtained except in low QLDs. In the 1/R control condition, relatively high correlation between mLAP and NPA could be obtained. In estimation of mLAP using the correlating function of individual goat, fairly good correlation was obtained between measured mLAP and estimated mLAP. Despite that further studies are necessary, it was demonstrated that the concept of the LAP estimation could be possible.
authors.affiliation: Department of Biomedical Engineering, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
authors.forename: Sheng-Yuan
authors.initials: SY
authors.lastname: Wu
authors.forename: Itsuro
authors.initials: I
authors.lastname: Saito
authors.forename: Takashi
authors.initials: T
authors.lastname: Isoyama
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Inoue
authors.forename: Masami
authors.initials: M
authors.lastname: Sato
authors.forename: Shintaro
authors.initials: S
authors.lastname: Hara
authors.forename: Xin-Yang
authors.initials: XY
authors.lastname: Li
authors.forename: Terumi
authors.initials: T
authors.lastname: Yurimoto
authors.forename: Haruka
authors.initials: H
authors.lastname: Murakami
authors.forename: Yukino
authors.initials: Y
authors.lastname: Kawase
authors.forename: Toshiya
authors.initials: T
authors.lastname: Ono
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Abe
mesh_terms: D000818:Animals; D062185:Atrial Pressure / Q000502:physiology*; D001783:Blood Flow Velocity / Q000502:physiology; D002302:Cardiac Output / Q000502:physiology*; D005260:Female; D006041:Goats; D006339:Heart Rate / Q000502:physiology*; D006354:Heart, Artificial; D006439:Hemodynamics / Q000502:physiology