Each year, mechanical heart valves (MHV's) are implanted in over 130,0000 patients. However, there are still several design-related problems associated with current commercial MHV's. We propose to develop a computational environment to improve the MHV design and evaluation process. This computational environment will consist of a geometric design module, coupled fluid-structure dynamics simulation code and visualization/animation software. In Phase I, we designed a generic two-dimensional bileaflet mitral MHV prototype and simulated it's response to physiologic ventricular contractions. Model predictions on valve motion and fluid dynamics showed close agreement with published in-vivo and in-vitro data. The valve opening angle and hinge recess were varied to demonstrate the utility of our design software. In Phase II, the design environment will be expanded to include three-dimensional (3D) virtual prototypes of bileaflet MHV's and 3D ventricular contraction. Extensive validation of model predictions will be done experimentally in collaboration with the Georgia Tech Bioengineering Center. A graphical-user-interface will be created for the design environment. Finally, the developed capability will be used to identify criteria for improved valve flow dynamics in bileaflet valves based on parameters such as occluder and hinge region geometry and maximum valve opening angle.
The computational MHV design environment will enable rapid, cost-effective prototyping and analysis of different valve designs. It will also enable detailed hemodynamic evaluation of current MHV designs. Valve manufacturers such as St. Jude Medical and Baxter have expressed strong interest in our proposed product. We will also market our capability to other valve and LVAD manufacturers, and to cardiovascular research labs.
