Present-day designs of mechanical prosthetic heart valves (MPHV) are far from ideal and significant complications such as hemolysis, platelet destruction, and thromboembolism-often arise after their implantation. These pathological conditions are believed to be caused by the exposure of blood elements to excessive hemodynamic stresses induced by the complex, turbulent flow field in the vicinity of the mechanical prosthesis. Therefore, a critical prerequisite for improving and further refining existing MPHV designs is the in-depth understanding of the flow fields they induce. A 5-year research plan is proposed herein aimed at developing and validating a state-of-the art numerical simulation tool for obtaining quantitatively accurate predictions of all flow phenomena occurring in prosthetic valves.
The specific aims for the proposed research program are: 1) To develop a highly accurate and efficient numerical method for simulating unsteady, three-dimensional flows in realistic bileaflet MPHV geometries; 2) To develop and implement in MPHV flow simulations advanced turbulence closure models capable of accurate predictions of transition to turbulence and relaminarization in pulsatile flows at physiological Reynolds numbers; 3) To conduct detailed laboratory experiments to obtain comprehensive data sets and use these data sets to validate and fine-tune the CFD model; and 4) To apply the CFD method to study in detail the structure of turbulence in bi-leaflet MPHV designs and explore its implications to clinically observed complications. The proposed CFD method will revolutionize current valve design and testing practices. The method will be capable of yielding descriptions of the valve flow fields at a level of detail not currently accessible by experiments alone, leading to substantial time and cost savings during the research and development phase. This work will also lead to a computational framework for assessing the likelihood that implantation of a given MPHV design may lead to thromboembolic complications.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL070262-02
Application #
6732724
Study Section
Surgery and Bioengineering Study Section (SB)
Program Officer
Baldwin, Tim
Project Start
2003-05-01
Project End
2007-04-30
Budget Start
2004-05-01
Budget End
2005-04-30
Support Year
2
Fiscal Year
2004
Total Cost
$327,598
Indirect Cost
Name
Georgia Institute of Technology
Department
Biomedical Engineering
Type
Schools of Engineering
DUNS #
097394084
City
Atlanta
State
GA
Country
United States
Zip Code
30332
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