title: Influence of a novel electrocardiogram-synchronized rotational-speed-change system of an implantable continuous-flow left ventricular assist device (EVAHEART) on hemolytic performance.
abstract: We developed a novel controller for a continuous-flow left ventricular assist device (EVAHEART) that can change the pump's rotational speed (RS) in synchronization with a patient's myocardial electrocardiogram (ECG) with the aim of facilitating cardiac recovery. We previously presented various applications of this system in animal models, but there remained a concern that the repeated acceleration and deceleration of the impeller may induce additional hemolysis. In this study, we evaluated the blood trauma and motor power consumption induced by our system in a mock circulation. We evaluated our system with a 60-bpm pulse frequency and a variance between the high and low RSs of 500 rpm (EVA-P; n = 4). The continuous modes of EVAHEART (EVA-C; n = 4) and ROTAFLOW (n = 4) were used as controls. The pumps were examined at a mean flow rate of 5.0 ± 0.2 L/min against a mean pressure head of 100 ± 3 mmHg for a 4-h period. As a result, the normalized indexes of the hemolysis levels of EVA-P and EVA-C were 0.0023 ± 0.0019 and 0.0023 ± 0.0025, respectively, and their difference was not significant. The estimated mean motor power consumptions of EVA-C and EVA-P were 6.24 ± 0.33 and 7.19 ± 0.93 W, respectively. When a novel ECG-synchronized RS-change system was applied to EVAHEART, the periodic RS change with a 500-rpm RS variance did not affect the hemolysis at a 60-bpm pulse frequency.
authors.affiliation: Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai Suita, Osaka, 565-8565, Japan, kishimoto.satoru.ri@mail.ncvc.go.jp.
authors.forename: Satoru
authors.initials: S
authors.lastname: Kishimoto
authors.forename: Kazuma
authors.initials: K
authors.lastname: Date
authors.forename: Mamoru
authors.initials: M
authors.lastname: Arakawa
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Takewa
authors.forename: Takashi
authors.initials: T
authors.lastname: Nishimura
authors.forename: Tomonori
authors.initials: T
authors.lastname: Tsukiya
authors.forename: Toshihide
authors.initials: T
authors.lastname: Mizuno
authors.forename: Nobumasa
authors.initials: N
authors.lastname: Katagiri
authors.forename: Yukihide
authors.initials: Y
authors.lastname: Kakuta
authors.forename: Daisuke
authors.initials: D
authors.lastname: Ogawa
authors.forename: Motonobu
authors.initials: M
authors.lastname: Nishimura
authors.forename: Eisuke
authors.initials: E
authors.lastname: Tatsumi
mesh_terms: D004562:Electrocardiography; D006339:Heart Rate; D006353:Heart-Assist Devices; D006461:Hemolysis / Q000502:physiology*; D008955:Models, Cardiovascular