The studies of this project are those of the ongoing use of juvenile sheep for evaluating cardiac valve pathology and pathophysiology. Previous years' studies have concentrated upon conventional hydraulic/hemodynamic evaluations of native and prosthetic cardiac valves, and upon the morphologic and physical characterization of calcific degeneration of bioprosthetic valves. Efforts during the current year explored the following areas: (1) studies of homograft mitral valve substitutes; and (2) studies of Doppler determined intracardiac flow dynamics. The first studies have demonstrated the feasibility of homograft mitral valve replacement, providing a unique mode for investigating mechanisms of bioprosthetic valve leaflet degeneration and mineralization. The current studies have added credence to the hypothesis that preimplantation glutaraldehyde treatment facilitates mineralization. Two-dimensional, color-encoded Doppler evaluations of intracardiac flow dynamics using fundamental physical theories of jet flux and momentum continuity preservation have provided quantitative volumetric information regarding valvular regurgitation.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Intramural Research (Z01)
Project #
1Z01HL002714-10
Application #
3878976
Study Section
Project Start
Project End
Budget Start
Budget End
Support Year
10
Fiscal Year
1990
Total Cost
Indirect Cost
Name
National Heart, Lung, and Blood Institute
Department
Type
DUNS #
City
State
Country
United States
Zip Code
Schmidt, M A; Ohazama, C J; Agyeman, K O et al. (1999) Real-time three-dimensional echocardiography for measurement of left ventricular volumes. Am J Cardiol 84:1434-9