TY - JOUR
T1 - A Single-opening&closing Valve Tester for Direct Measurement of Closing Volume of the Heart Valve
AU - Wang, Hao
AU - Cui, Zhan
AU - Zhou, Zhongxi
AU - He, Zhaoming
N1 - Funding Information:
HW contributed to conceptualization, performed the experiment, data analyses and wrote the manuscript; ZC performed the experiment; ZZ performed the analysis with constructive discussions; ZH contributed to the conception of the study. The datasets used or analyzed during the current study are available from the corresponding author on reasonable request. Hao Wang is the inventor of the single opening&closing tester. The other authors do not have conflicts of interest.
Publisher Copyright:
© 2021, Biomedical Engineering Society.
PY - 2022/2
Y1 - 2022/2
N2 - Purpose: The objective of this study was to develop a novel single opening&closing pulsatile flow in-vitro valve tester for direct measurement of closing volume of the heart valve. Methods: A single opening&closing valve tester was composed of a piston pump, valve mounting chamber, reservoir, measurement and control system. The piston pump was used to drive a valve to open and close with dictated flow which comprised three phases of accelerated, constant, and decelerated flow with six slopes. A high speed camera was used to record valve opening and closing images. Two pressure transducers across the tested valve were used to capture the ending time of valve closing which was verified by the high-speed photography. The closing time was measured and closing volume was calculated with a piston displacement volume during valve closing. A tilting disc valve and porcine mitral valve were tested. Results: There was a big difference in flowrate between the Transonic flowmeter and piston pump. The heart valve opened and closed under the dictated flow driven by the piston pump. The transvalvular pressure was minor during valve opening and then increased sharply during valve closing. The closing time varied approximately linearly with the slope of the decelerated flow and was comparable between the two methods by the transvalvular pressure and high-speed photography. The closing volumes did not change much with the slope of the decelerated flow and were 7.0 ± 1.0 and 14.0 ± 1.5 mL for the tilting disc valve and mitral valve, respectively. Conclusion: Pulsatile flow is challenging to the flowmeter. A novel single opening&closing pulsatile flow in-vitro valve tester for the heart valve has successfully been developed and can be used to simulate and evaluate the opening and closing hemodynamics of the heart valve. The tester can be used to measure valve closing volume and time accurately with a standardized testing protocol free from effect of other components such as the resistance, compliance units and auxiliary valve in the continuous pulsatile flow valve tester.
AB - Purpose: The objective of this study was to develop a novel single opening&closing pulsatile flow in-vitro valve tester for direct measurement of closing volume of the heart valve. Methods: A single opening&closing valve tester was composed of a piston pump, valve mounting chamber, reservoir, measurement and control system. The piston pump was used to drive a valve to open and close with dictated flow which comprised three phases of accelerated, constant, and decelerated flow with six slopes. A high speed camera was used to record valve opening and closing images. Two pressure transducers across the tested valve were used to capture the ending time of valve closing which was verified by the high-speed photography. The closing time was measured and closing volume was calculated with a piston displacement volume during valve closing. A tilting disc valve and porcine mitral valve were tested. Results: There was a big difference in flowrate between the Transonic flowmeter and piston pump. The heart valve opened and closed under the dictated flow driven by the piston pump. The transvalvular pressure was minor during valve opening and then increased sharply during valve closing. The closing time varied approximately linearly with the slope of the decelerated flow and was comparable between the two methods by the transvalvular pressure and high-speed photography. The closing volumes did not change much with the slope of the decelerated flow and were 7.0 ± 1.0 and 14.0 ± 1.5 mL for the tilting disc valve and mitral valve, respectively. Conclusion: Pulsatile flow is challenging to the flowmeter. A novel single opening&closing pulsatile flow in-vitro valve tester for the heart valve has successfully been developed and can be used to simulate and evaluate the opening and closing hemodynamics of the heart valve. The tester can be used to measure valve closing volume and time accurately with a standardized testing protocol free from effect of other components such as the resistance, compliance units and auxiliary valve in the continuous pulsatile flow valve tester.
KW - Heart valve
KW - Regurgitation
KW - Replacement and repair
KW - Standardized pulsatile tester
UR - http://www.scopus.com/inward/record.url?scp=85108845470&partnerID=8YFLogxK
U2 - 10.1007/s13239-021-00560-9
DO - 10.1007/s13239-021-00560-9
M3 - Article
C2 - 34173164
AN - SCOPUS:85108845470
SN - 1869-408X
VL - 13
SP - 80
EP - 89
JO - Cardiovascular Engineering and Technology
JF - Cardiovascular Engineering and Technology
IS - 1
ER -