Changing the speed of left ventricular assist devices (LVADs) cyclically may be useful to restore aortic pulsatility; however, the effects of this pulsation on right ventricular (RV) function are unknown. This study investigates the effects of direct ventricular interaction by quantifying the amount of wave energy created by RV contraction when axial and centrifugal LVADs are used to assist the left ventricle. In 4 anesthetized pigs, pressure and flow were measured in the main pulmonary artery and wave intensity analysis was used to identify and quantify the energy of waves created by the RV. The axial pump depressed the intensity of waves created by RV contraction compared with the centrifugal pump. In both pump designs, there were only minor and variable differences between the continuous and pulsed operation on RV function. The axial pump causes the RV to contract with less energy compared with a centrifugal design. Diminishing the ability of the RV to produce less energy translates to less pressure and flow produced, which may lead to LVAD-induced RV failure. The effects of pulsed LVAD operation on the RV appear to be minimal during acute observation of healthy hearts. Further study is necessary to uncover the effects of other modes of speed modulation with healthy and unhealthy hearts to determine if pulsed operation will benefit patients by reducing LVAD complications.
From the *Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Canada
†Department of Surgery, Bonde Artificial Heart Laboratory, Yale School of Medicine, New Haven, CT
‡Department of Surgery, Bonde Artificial Heart Laboratory, Yale School of Medicine, New Haven, CT
§Department of Electrical and Computer Engineering, California State University, Northridge, CA
¶Department of Surgery, Cardiac Surgery, Yale School of Medicine, New Haven, CT.
Submitted for consideration December 2017; accepted for publication in revised form April 2018.
Disclosure: The authors have no conflicts of interest to report.
Supported by NIH/NHLBI grant# R21HL118611. No relationships with industry to report.
Correspondence: Pramod Bonde, MD, FACS, Center for Advanced Heart Failure and Transplantation, Yale School of Medicine, Yale New Haven Hospital, 330 Cedar Street, 204 Boardman, PO Box: 208039, New Haven, CT 06520. Email: email@example.com.