TY - JOUR
T1 - Arterial pulsatility improvement in a feedback-controlled continuous flow left ventricular assist device: An ex-vivo experimental study
AU - Bozkurt, Selim
AU - van Tuijl, Sjoerd
AU - Schampaert, Stephanie
AU - van de Vosse, Frans N.
AU - Rutten, Marcel C. M.
PY - 2014/10
Y1 - 2014/10
N2 - Continuous flow left ventricular assist devices (CF-LVADs) reduce arterial pulsatility, which may cause long-term complications in the cardiovascular system. The aim of this study is to improve the pulsatility by driving a CF-LVAD at a varying speed, synchronous with the cardiac cycle in an ex-vivo experiment. A Micromed DeBakey pump was used as CF-LVAD. The heart was paced at 140 bpm to obtain a constant cardiac cycle for each heartbeat. First, the CF-LVAD was operated at a constant speed. At varying-speed CF-LVAD assistance, the pump was driven such that the same mean pump output was generated. For synchronization purposes, an algorithm was developed to trigger the CF-LVAD each heartbeat. The pump flow rate was selected as the control variable and a reference model was used for regulating the CF-LVAD speed. Continuous and varying-speed CF-LVAD assistance provided the same mean arterial pressure and flow rate, while the index of pulsatility doubled in both arterial pressure and pump flow rate signals under pulsatile pump speed support. This study shows the possibility of improving the pulsatility in CF-LVAD support by regulating pump speed over a cardiac cycle without compromising the overall level of support. IPEM.
AB - Continuous flow left ventricular assist devices (CF-LVADs) reduce arterial pulsatility, which may cause long-term complications in the cardiovascular system. The aim of this study is to improve the pulsatility by driving a CF-LVAD at a varying speed, synchronous with the cardiac cycle in an ex-vivo experiment. A Micromed DeBakey pump was used as CF-LVAD. The heart was paced at 140 bpm to obtain a constant cardiac cycle for each heartbeat. First, the CF-LVAD was operated at a constant speed. At varying-speed CF-LVAD assistance, the pump was driven such that the same mean pump output was generated. For synchronization purposes, an algorithm was developed to trigger the CF-LVAD each heartbeat. The pump flow rate was selected as the control variable and a reference model was used for regulating the CF-LVAD speed. Continuous and varying-speed CF-LVAD assistance provided the same mean arterial pressure and flow rate, while the index of pulsatility doubled in both arterial pressure and pump flow rate signals under pulsatile pump speed support. This study shows the possibility of improving the pulsatility in CF-LVAD support by regulating pump speed over a cardiac cycle without compromising the overall level of support. IPEM.
KW - CF-LVAD
KW - Flow rate control
KW - Arterial pulsatility
KW - Ex-vivo experiment
KW - Varying speed over a cardiac cycle
U2 - 10.1016/j.medengphy.2014.07.005
DO - 10.1016/j.medengphy.2014.07.005
M3 - Article
C2 - 25066581
SN - 1350-4533
VL - 36
SP - 1288
EP - 1295
JO - Medical Engineering & Physics
JF - Medical Engineering & Physics
IS - 10
ER -