title: Pulsatile support using a rotary left ventricular assist device with an electrocardiography-synchronized rotational speed control mode for tracking heart rate variability.
abstract: We previously developed a novel control system for a continuous-flow left ventricular assist device (LVAD), the EVAHEART, and demonstrated that sufficient pulsatility can be created by increasing its rotational speed in the systolic phase (pulsatile mode) in a normal heart animal model. In the present study, we assessed this system in its reliability and ability to follow heart rate variability. We implanted an EVAHEART via left thoracotomy into five goats for the Study for Fixed Heart Rate with ventricular pacing at 80, 100, 120 and 140 beats/min and six goats for the Study for native heart rhythm. We tested three modes: the circuit clamp, the continuous mode and the pulsatile mode. In the pulsatile mode, rotational speed was increased during the initial 35 % of the RR interval by automatic control based on the electrocardiogram. Pulsatility was evaluated by pulse pressure and dP/dt max of aortic pressure. As a result, comparing the pulsatile mode with the continuous mode, the pulse pressure was 28.5 ± 5.7 vs. 20.3 ± 7.9 mmHg, mean dP/dt max was 775.0 ± 230.5 vs 442.4 ± 184.7 mmHg/s at 80 bpm in the study for fixed heart rate, respectively (P < 0.05). The system successfully determined the heart rate to be 94.6 % in native heart rhythm. Furthermore, pulse pressure was 41.5 ± 7.9 vs. 27.8 ± 5.6 mmHg, mean dP/dt max was 716.2 ± 133.9 vs 405.2 ± 86.0 mmHg/s, respectively (P < 0.01). In conclusion, our newly developed the pulsatile mode for continuous-flow LVADs reliably provided physiological pulsatility with following heart rate variability.
authors.affiliation: Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan. a_mamoru@mbn.nifty.com.|Department of Cardiovascular Surgery, Saitama Medical Center, Jichi Medical University, Saitama, Japan. a_mamoru@mbn.nifty.com.
authors.forename: Mamoru
authors.initials: M
authors.lastname: Arakawa
authors.affiliation: Department of Cardiac Surgery, Tokyo Metropolitan Geriatric Hospital, 35-2 Sakae-cho, Itabashi-ku, Tokyo, 173-0015, Japan. takashin-tyk@umin.ac.jp.
authors.forename: Takashi
authors.initials: T
authors.lastname: Nishimura
authors.affiliation: Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Takewa
authors.affiliation: Department of Cardiothoracic Surgery, University of Tokyo, Toyo, Japan.
authors.forename: Akihide
authors.initials: A
authors.lastname: Umeki
authors.affiliation: Department of Cardiothoracic Surgery, University of Tokyo, Toyo, Japan.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Ando
authors.affiliation: Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan.
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Kishimoto
authors.affiliation: Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Kishimoto
authors.affiliation: Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Fujii
authors.affiliation: Department of Cardiothoracic Surgery, University of Tokyo, Toyo, Japan.
authors.forename: Kazuma
authors.initials: K
authors.lastname: Date
authors.affiliation: Department of Cardiac Surgery, Tokyo Metropolitan Geriatric Hospital, 35-2 Sakae-cho, Itabashi-ku, Tokyo, 173-0015, Japan.
authors.forename: Shunei
authors.initials: S
authors.lastname: Kyo
authors.affiliation: Department of Cardiovascular Surgery, Saitama Medical Center, Jichi Medical University, Saitama, Japan.
authors.forename: Hideo
authors.initials: H
authors.lastname: Adachi
authors.affiliation: Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan.
authors.forename: Eisuke
authors.initials: E
authors.lastname: Tatsumi
mesh_terms: D000818:Animals; D001794:Blood Pressure; D004195:Disease Models, Animal; D004562:Electrocardiography; D006041:Goats; D006321:Heart / Q000502:physiology; D006333:Heart Failure / Q000628:therapy*; D006339:Heart Rate; D006353:Heart-Assist Devices; D011673:Pulsatile Flow; D015203:Reproducibility of Results; D013599:Systole
keywords: EVAHEART; LVAD; Rotary blood pump