TY - JOUR
T1 - Influence of left ventricular assist device pressure-flow characteristic on exercise physiology
T2 - Assessment with a verified numerical model
AU - Graefe, Roland
AU - Henseler, Andreas
AU - Körfer, Reiner
AU - Meyns, Bart
AU - Fresiello, Libera
N1 - Funding Information:
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: L.F. is supported by the Frans Van de Werf Fund and by the Belgian Fund for Cardiac Surgery. R.G., A.H., and R.K. thank the Erich and Hanna Klessmann foundation for its support.
Publisher Copyright:
© The Author(s) 2019.
PY - 2019/9/1
Y1 - 2019/9/1
N2 - Current left ventricular assist devices are designed to reestablish patient’s hemodynamics at rest but they lack the suitability to sustain the heart adequately during physical exercise. Aim of this work is to assess the performance during exercise of a left ventricular assist device with flatter pump pressure-flow characteristic and increased pressure sensitivity (left ventricular assist device 1) and to compare it to the performance of a left ventricular assist device with a steeper characteristic (left ventricular assist device 2). The two left ventricular assist devices were tested at constant rotational speed with a verified computational cardiorespiratory simulator reproducing an average left ventricular assist device patient response to exercise (EXE↑) and a left ventricular assist device patient with no chronotropic and inotropic response (EXE→). According to the results, left ventricular assist device 1 pumps a higher flow than left ventricular assist device 2 both at EXE↑ (6.3 vs 5.6 L/min) and at EXE→ (6.7 vs 6.1 L/min), thus it better unloads the left ventricle. Left ventricular assist device 1 increases the power delivered to the circulation from 0.63 W at rest to 0.67 W at EXE↑ and 0.82 W at EXE→, while left ventricular assist device 2 power shows even a minimal decrease. Left ventricular assist device 1 better sustains exercise hemodynamics and can provide benefits in terms of exercise performance, especially for patients with a poor residual left ventricular function, for whom the heart can hardly accommodate an increase of cardiac output.
AB - Current left ventricular assist devices are designed to reestablish patient’s hemodynamics at rest but they lack the suitability to sustain the heart adequately during physical exercise. Aim of this work is to assess the performance during exercise of a left ventricular assist device with flatter pump pressure-flow characteristic and increased pressure sensitivity (left ventricular assist device 1) and to compare it to the performance of a left ventricular assist device with a steeper characteristic (left ventricular assist device 2). The two left ventricular assist devices were tested at constant rotational speed with a verified computational cardiorespiratory simulator reproducing an average left ventricular assist device patient response to exercise (EXE↑) and a left ventricular assist device patient with no chronotropic and inotropic response (EXE→). According to the results, left ventricular assist device 1 pumps a higher flow than left ventricular assist device 2 both at EXE↑ (6.3 vs 5.6 L/min) and at EXE→ (6.7 vs 6.1 L/min), thus it better unloads the left ventricle. Left ventricular assist device 1 increases the power delivered to the circulation from 0.63 W at rest to 0.67 W at EXE↑ and 0.82 W at EXE→, while left ventricular assist device 2 power shows even a minimal decrease. Left ventricular assist device 1 better sustains exercise hemodynamics and can provide benefits in terms of exercise performance, especially for patients with a poor residual left ventricular function, for whom the heart can hardly accommodate an increase of cardiac output.
KW - cardiovascular modeling
KW - exercise physiology
KW - Ventricular assist device
UR - http://www.scopus.com/inward/record.url?scp=85066854351&partnerID=8YFLogxK
U2 - 10.1177/0391398819846126
DO - 10.1177/0391398819846126
M3 - Article
C2 - 31104554
AN - SCOPUS:85066854351
SN - 0391-3988
VL - 42
SP - 490
EP - 499
JO - The International journal of artificial organs
JF - The International journal of artificial organs
IS - 9
ER -