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Related Experiment Video

Updated: Jul 16, 2025

Protocol for Relative Hydrodynamic Assessment of Tri-leaflet Polymer Valves

Protocol for Relative Hydrodynamic Assessment of Tri-leaflet Polymer Valves

Published on: October 17, 2013

Effect of valve leaflet surface patterning on valve hydrodynamic performance.

Aili Wang¹, Yumiao Wang¹, Wanbing Liu²

¹State Key Laboratory of Cardiovascular Disease, FuWai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, PR China.

The International Journal of Artificial Organs

|September 12, 2023

Summary

This summary is machine-generated.

Altering pyrolytic carbon micro-structure with a parallel-groove pattern on artificial heart valve leaflets impacts hydrodynamic performance, affecting mean pressure gradient, effective orifice area, and regurgitation fraction.

Keywords:

Surface patterning heart valve prosthesis hemodynamics pulse duplicator

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Combining 3D-Printing and Electrospinning to Manufacture Biomimetic Heart Valve Leaflets

Combining 3D-Printing and Electrospinning to Manufacture Biomimetic Heart Valve Leaflets

Published on: March 23, 2022

Area of Science:

Biomedical Engineering
Materials Science
Cardiovascular Research

Background:

Artificial heart valves are crucial for treating valvular heart disease.
The pyrolytic carbon microstructure influences the performance of mechanical heart valves.
Understanding these effects is key to improving valve design and patient outcomes.

Purpose of the Study:

To investigate how the micro-structure of pyrolytic carbon on artificial heart valve leaflets affects their hydrodynamic performance.
To assess the impact of a laser-etched parallel-groove pattern on key hemodynamic parameters.

Main Methods:

Bileaflet mechanical valves (GKS 23 and 29 A) were tested according to ISO5840.
Hemodynamic parameters including mean pressure gradient (MPG), regurgitation fraction (RF), and effective orifice area (EOA) were measured.
A parallel-groove pattern was created on leaflet surfaces via laser etching, and valves were re-tested.

Main Results:

The parallel-groove pattern altered MPG, EOA, and RF.
MPG generally increased post-patterning.
EOA showed varied responses (larger in 23 A, smaller in 29 A), with RF exhibiting an inverse relationship.
RF decreased at 5 L/min (45 bpm) but showed complex changes at 7 L/min (70 bpm).

Conclusions:

Surface micro-structuring of pyrolytic carbon leaflets significantly influences the hydrodynamic performance of artificial heart valves.
The parallel-groove pattern offers a method to modulate valve hemodynamics, though effects vary with valve size and flow conditions.