title: Analysis of baroreflex sensitivity during undulation pump ventricular assist device support.
abstract: The aim of this study was to examine the baroreflex sensitivity (BRS), which involves the autonomic nervous system, in a goat with a chronically implanted undulation pump ventricular assist device (UPVAD). The UPVAD involved transforming the rotation of a brushless DC motor into an undulating motion by a disc attached via a special linking mechanism, and a jellyfish valve in the outflow cannula to prevent diastolic backflow. The pump was implanted into the thoracic cavity of a goat by a left thoracotomy, and the inflow and outflow cannulae were sutured to the apex of the left ventricle and to the descending aorta, respectively. The driving cable was wired percutaneously to an external controller. Electrocardiogram and hemodynamic waveforms were recorded at a sampling frequency of 1 kHz. BRS was determined when awake by the slope of the linear regression of R-R interval against mean arterial pressure changes, which were induced by the administration of methoxamine hydrochloride, both with continuous driving of the UPVAD as well as without assistance. BRS values during the UPVAD support and without assistance were 1.60 +/- 0.30 msec/mm Hg and 0.98 +/- 0.22 msec/mm Hg (n = 5, P < 0.05), respectively. BRS was significantly improved during left ventricular assistance. Therefore, UPVAD support might decrease sympathetic nerve activity and increase parasympathetic nerve activity to improve both microcirculation and organ function.
authors: Department of Medical Engineering and Cardiology, Institute of Development, Aging and Cancer, Tohoku University, Aoba-ku, Sendai, Japan. hongjianliu63@yahoo.co.jp
authors: Hongjian
authors: H
authors: Liu
authors: Yasuyuki
authors: Y
authors: Shiraishi
authors: Xiumin
authors: X
authors: Zhang
authors: Hojin
authors: H
authors: Song
authors: Yoshifumi
authors: Y
authors: Saijo
authors: Atsushi
authors: A
authors: Baba
authors: Tomoyuki
authors: T
authors: Yambe
authors: Yusuke
authors: Y
authors: Abe
authors: Kou
authors: K
authors: Imachi
mesh_terms: D000818:Animals; D017704:Baroreflex / Q000187:drug effects; D004562:Electrocardiography; D004867:Equipment Design; D006041:Goats; D006352:Heart Ventricles / Q000187:drug effects; D006353:Heart-Assist Devices; D018056:Hemorheology / Q000187:drug effects; D008297:Male; D008729:Methoxamine / Q000494:pharmacology / Q000627:therapeutic use; D019919:Prosthesis Implantation; D014662:Vasoconstrictor Agents / Q000494:pharmacology / Q000627:therapeutic use
chemical_list: D014662:Vasoconstrictor Agents; D008729:Methoxamine