This is a continuation of a project to characterize the ultrasonic properties of myocardial tissue in health and disease and to utilize this knowledge in the development of methods to assess regional myocardial perfusion, function, and viability. They have found in previous work that velocity, backscatter, and attenuation of ultrasound vary substantially with the angle of insonification relative to the local arrangement of fibers in the myocardial walls. This anisotropy has largely been ignored, but is thought to be responsible for the drop out of lateral wall echoes in some views of the heart. It is especially important in tissue characterization where subtle changes in ultrasonic properties caused by disease or other abnormalities must be detected in the face of alterations due to angle of incidence. Contrast echocardiography has the potential for assessment of regional myocardial perfusion, but they have found that anisotropy of backscatter and attenuation confounds these measurements as well. In this competitive renewal they propose to: 1) measure the anisotropy of ultrasonic backscatter, attenuation, and velocity in myocardial tissue and delineate the responsible mechanisms; 2) develop strategies for exploiting the knowledge and overcoming the potential difficulties anisotropy presents in echocardiographic imaging, tissue characterization, and contrast echocardiography; and 3) provide baseline knowledge of the anisotropy of myocardial mechanical and elastic properties to improve understanding of cardiac mechanics in normal and diseased hearts.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Method to Extend Research in Time (MERIT) Award (R37)
Project #
5R37HL040302-13
Application #
6182311
Study Section
Special Emphasis Panel (ZRG7-SSS-W (09))
Project Start
1988-04-01
Project End
2003-03-31
Budget Start
2000-04-01
Budget End
2001-03-31
Support Year
13
Fiscal Year
2000
Total Cost
$234,788
Indirect Cost
Name
Washington University
Department
Physics
Type
Schools of Arts and Sciences
DUNS #
062761671
City
Saint Louis
State
MO
Country
United States
Zip Code
63130
Lloyd, Christopher W; Shmuylovich, Leonid; Holland, Mark R et al. (2011) The diastolic function to cyclic variation of myocardial ultrasonic backscatter relation: the influence of parameterized diastolic filling (PDF) formalism determined chamber properties. Ultrasound Med Biol 37:1185-95
Hoffman, Joseph J; Johnson, Benjamin L; Holland, Mark R et al. (2011) Layer-dependent variation in the anisotropy of apparent integrated backscatter from human coronary arteries. Ultrasound Med Biol 37:632-41
Holland, Mark R; Gibson, Allyson A; Bauer, Adam Q et al. (2010) Echocardiographic tissue characterization demonstrates differences in the left and right sides of the ventricular septum. Ultrasound Med Biol 36:1653-61
Gibson, Allyson A; Schaffer, Jean E; Peterson, Linda R et al. (2009) Quantitative analysis of the magnitude and time delay of cyclic variation of myocardial backscatter from asymptomatic type 2 diabetes mellitus subjects. Ultrasound Med Biol 35:1458-67
Bauer, Adam Q; Anderson, Christian C; Holland, Mark R et al. (2009) Bone sonometry: reducing phase aberration to improve estimates of broadband ultrasonic attenuation. J Acoust Soc Am 125:522-9
Anderson, Christian C; Marutyan, Karen R; Holland, Mark R et al. (2008) Interference between wave modes may contribute to the apparent negative dispersion observed in cancellous bone. J Acoust Soc Am 124:1781-9
Bauer, Adam Q; Marutyan, Karen R; Holland, Mark R et al. (2008) Negative dispersion in bone: the role of interference in measurements of the apparent phase velocity of two temporally overlapping signals. J Acoust Soc Am 123:2407-14
Lloyd, Christopher W; Wallace, Kirk D; Holland, Mark R et al. (2007) Plane wave source with minimal harmonic distortion for investigating nonlinear acoustic properties. J Acoust Soc Am 122:91-6
Baldwin, Steven L; Yang, Min; Marutyan, Karen R et al. (2007) Ultrasonic detection of the anisotropy of protein cross linking in myocardium at diagnostic frequencies. IEEE Trans Ultrason Ferroelectr Freq Control 54:1360-9
Bauer, Adam Q; Marutyan, Karen R; Holland, Mark R et al. (2007) Is the Kramers-Kronig relationship between ultrasonic attenuation and dispersion maintained in the presence of apparent losses due to phase cancellation? J Acoust Soc Am 122:222-8

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