TY - JOUR
T1 - Impact of superhydrophobicity on the fluid dynamics of a bileaflet mechanical heart valve
AU - Hatoum, Hoda
AU - Vallabhuneni, Sravanthi
AU - Kota, Arun Kumar
AU - Bark, David L.
AU - Popat, Ketul C.
AU - Dasi, Lakshmi Prasad
N1 - Funding Information:
The research done was partly supported by National Institutes of Health (NIH) under Award Number R01HL135505 , R21HL139208, the American Heart Association (AHA) under Award Number 19POST34380804 and and the National Science Foundation (NSF) under Award Number 1751628 .
Publisher Copyright:
© 2020
PY - 2020/10
Y1 - 2020/10
N2 - Objective: The objective of this study is to evaluate the impact of superhydrophobic coating on the hemodynamics and turbulence characteristics of a bileaflet mechanical valve in the context of evaluating blood damage potential. Methods: Two 3D printed bileaflet mechanical valves were hemodynamically tested in a pulse duplicator under physiological pressure and flow conditions. The leaflets of one of the two valves were sprayed with a superhydrophobic coating. Particle Image Velocimetry was performed. Pressure gradients (PG), effective orifice areas (EOA), Reynolds shear stresses (RSS) and instantaneous viscous shear stresses (VSS) were calculated. Results: (a) Without SH coating, the PG was found to be 14.53 ± 0.7 mmHg and EOA 1.44 ± 0.06 cm2. With coating, the PG obtained was 15.21 ± 1.7 mmHg and EOA 1.39 ± 0.07 cm2; (b) during peak systole, the magnitude of RSS with SH coating (110Pa) exceeded that obtained without SH coating (40 Pa) with higher probabilities to develop higher RSS in the immediate wake of the leaflet; (c) The magnitudes range of instantaneous VSS obtained with SH coating were slightly larger than those obtained without SH coating (7.0 Pa versus 5.0 Pa). Conclusion: With Reynolds Shear Stresses and instantaneous Viscous Shear Stresses being correlated with platelet damage, SH coating did not lead to their decrease. While SH coating is known to improve surface properties such as reduced platelet or clot adhesion, the relaxation of the slip condition does not necessarily improve overall hemodynamic performance for the bileaflet mechanical valve design.
AB - Objective: The objective of this study is to evaluate the impact of superhydrophobic coating on the hemodynamics and turbulence characteristics of a bileaflet mechanical valve in the context of evaluating blood damage potential. Methods: Two 3D printed bileaflet mechanical valves were hemodynamically tested in a pulse duplicator under physiological pressure and flow conditions. The leaflets of one of the two valves were sprayed with a superhydrophobic coating. Particle Image Velocimetry was performed. Pressure gradients (PG), effective orifice areas (EOA), Reynolds shear stresses (RSS) and instantaneous viscous shear stresses (VSS) were calculated. Results: (a) Without SH coating, the PG was found to be 14.53 ± 0.7 mmHg and EOA 1.44 ± 0.06 cm2. With coating, the PG obtained was 15.21 ± 1.7 mmHg and EOA 1.39 ± 0.07 cm2; (b) during peak systole, the magnitude of RSS with SH coating (110Pa) exceeded that obtained without SH coating (40 Pa) with higher probabilities to develop higher RSS in the immediate wake of the leaflet; (c) The magnitudes range of instantaneous VSS obtained with SH coating were slightly larger than those obtained without SH coating (7.0 Pa versus 5.0 Pa). Conclusion: With Reynolds Shear Stresses and instantaneous Viscous Shear Stresses being correlated with platelet damage, SH coating did not lead to their decrease. While SH coating is known to improve surface properties such as reduced platelet or clot adhesion, the relaxation of the slip condition does not necessarily improve overall hemodynamic performance for the bileaflet mechanical valve design.
KW - Blood damage
KW - Reynolds shear stress
KW - Superhydrophobicity
KW - Turbulence
KW - Viscous shear stress
UR - http://www.scopus.com/inward/record.url?scp=85088535441&partnerID=8YFLogxK
U2 - 10.1016/j.jmbbm.2020.103895
DO - 10.1016/j.jmbbm.2020.103895
M3 - Article
C2 - 32957201
AN - SCOPUS:85088535441
VL - 110
JO - Journal of the Mechanical Behavior of Biomedical Materials
JF - Journal of the Mechanical Behavior of Biomedical Materials
SN - 1751-6161
M1 - 103895
ER -