SOUTHERN METHODIST UNIVERSITY
DEPARTMENT OF MECHANICAL ENGINEERING
SOUTHWEST MECHANICS LECTURE SERIES
HEMODYNAMICS AND ATHEROSCLEROSIS: ARTERIES TO CELLS
AND BACK AGAIN
Prof. Don P. Giddens, Dean – College of Engineering – Georgia Institute of Technology
Lawrence L. Gellerstedt, Jr. Chair in Bioengineering,
Georgia Research Alliance Eminent Scholar
Interactions between flowing blood and the artery wall have been the subject of biomechanical study for
decades, motivated largely by the fact that cardiovascular and cerebrovascular diseases are the most frequent
cause of death in advanced societies. A quarter of a century ago, one of the most common diagnostic applications of hemodynamics was the use of the stethoscope to detect bruits, or turbulent-generated sounds, in the
carotid artery, a very important example of fluid-solid interaction. The advent of noninvasive methods of
measuring blood flow and velocity - first, Doppler ultrasound and, more recently, MRI - has led to much more
sophisticated and definitive diagnostic procedures which rely on fluid mechanics principles.
Interest has not been restricted to diagnostic uses, however. It was recognized that hemodynamics may
play a role in the development of arterial disease, notably, though not exclusively, the localization of atherosclerotic plaques. The tendency for plaques to be focal and to develop in rather predictable locations tempted
investigators to postulate a variety of cause-effect relationships between atherogenesis and fluid dynamics.
Comparisons of intimal thickening in human arteries with in vitro hemodynamic model studies suggests that
plaques have a tendency to develop in areas where the mean wall shear stress is fairly low in magnitude, not
where the wall shear stress is high. Oscillations in wall shear may also have an effect, as well as the relative
length of time a blood borne particle spends near a particular site on the artery wall. However, these concepts
are based on observations, and the search for mechanisms has led to efforts to understand interactions between
blood and the artery under physiologic conditions.
The key to understanding hemodynamic-artery wall interactions lies at the cell and molecular level.
Yet, we know that the hemodynamic environment in vivo may be quite complex at sites of atherogenesis. The
challenge for the next decade will be to integrate the macroscopic and microscopic worlds. How does knowledge gained in cell culture research become incorporated into the larger fluid dynamics picture? How will
studies in animal models be interpreted with regard to human vessels? How might biological information gathered under relatively simple laboratory conditions be developed into quantitative models that can be incorporated into describing and, more importantly, predicting how flowing blood and the artery wall interact? Biomechanics will undoubtedly be one of the major factors in bridging the molecular world with an understanding of
atherosclerosis in humans.
Biography - Don P. Giddens is Dean of the College of Engineering, the Lawrence L. Gellerstedt, Jr. Chair in Bioengineering, and Georgia Research Alliance Eminent Scholar at the Georgia Institute of Technology. Giddens joined the Georgia Tech faculty
in 1968. In 1992 he left his position as the Chair of Aerospace Engineering to serve as the Dean of the Whiting School of Engineering
and Professor of Mechanical Engineering at The Johns Hopkins University until 1997 when he rejoined Georgia Tech to serve as
Chair of The Wallace H. Coulter Department of Biomedical Engineering, a joint department between Georgia Tech’s College of
Engineering and Emory University’s School of Medicine. In July 2002, Giddens became the Dean of the College of Engineering at
Georgia Tech.
Date:
Tuesday, February 21, 2006
Location: Room 110, Junkins Engineering Building
Lecture will begin promptly at
1:30 PM
NOTE: On-campus ME Graduate students are required to attend. ME Undergrads are encouraged to attend