title: A novel counterpulsation mode of rotary left ventricular assist devices can enhance myocardial perfusion.
abstract: The effect of rotary left ventricular assist devices (LVADs) on myocardial perfusion has yet to be clearly elucidated, and several studies have shown decreased coronary flow under rotary LVAD support. We have developed a novel pump controller that can change its rotational speed (RS) in synchronization with the native cardiac cycle. The aim of our study was to evaluate the effect of counterpulse mode, which increases the RS in diastole, during coronary perfusion. Experiments were performed on ten adult goats. The EVAHEART LVAD was installed by the left ventricular uptake and the descending aortic return. Ascending aortic flow, pump flow, and coronary flow of the left main trunk were monitored. Coronary flow was compared under four conditions: circuit-clamp, continuous mode (constant pump speed), counterpulse mode (increased pump speed in diastole), and copulse mode (increased pump speed in systole). There were no significant baseline changes between these groups. In counterpulse mode, coronary flow increased significantly compared with that in continuous mode. The waveform analysis clearly revealed that counterpulse mode mainly resulted in increased diastolic coronary flow. In conclusion, counterpulse mode of rotary LVADs can enhance myocardial perfusion. This novel drive mode can provide great benefits to the patients with end-stage heart failure, especially those with ischemic etiology.
authors.affiliation: Department of Artificial Organ, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, Japan. masandoo@hotmail.com
authors.forename: Masahiko
authors.initials: M
authors.lastname: Ando
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Takewa
authors.forename: Takashi
authors.initials: T
authors.lastname: Nishimura
authors.forename: Kenji
authors.initials: K
authors.lastname: Yamazaki
authors.forename: Shunei
authors.initials: S
authors.lastname: Kyo
authors.forename: Minoru
authors.initials: M
authors.lastname: Ono
authors.forename: Tomonori
authors.initials: T
authors.lastname: Tsukiya
authors.forename: Toshihide
authors.initials: T
authors.lastname: Mizuno
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Taenaka
authors.forename: Eisuke
authors.initials: E
authors.lastname: Tatsumi
mesh_terms: D000818:Animals; D015908:Counterpulsation; D006041:Goats; D006321:Heart / Q000502:physiology*; D006353:Heart-Assist Devices; D009206:Myocardium; D016277:Ventricular Function, Left / Q000502:physiology*