The goal of this proposal is to develop a biomechanical model for artery buckling, and to determine the roles of mechanical factors in artery buckling, kinking and twisting. Artery buckling creates significant vascular problems. The educational objective is to integrate the proposed research into the education of undergraduate and graduate students, with a special emphasis on recruiting Hispanic students. The project is a combination of experimental and theoretical work. In the long term, the project can have a significant impact on the study, treatment and prevention of cardiovascular diseases, with possible applications to other biological tubular systems (e.g. veins, ureters).

Project Report

The overall goals of this CAREER project were to establish a biomechanical model for artery buckling and integrate the research with biomedical engineering teaching and minority student training activities. Artery tortuosity is a significant vascular problem that often occurs in various arteries and veins associated with aging, hypertension and atherosclerosis, but the related biomechanical study was lacking. The research objective of this project was to establish a biomechanical model of artery buckling to determine the role of mechanical factors in artery buckling. Major Results: This project established a new theory of artery buckling and proposed it as a mechanism for artery tortuosity. By combining theoretical, numerical and experimental approaches, we found that both arteries and veins buckle into tortuous shapes due to a higher lumen pressure, lower axial stretch, or weakened wall. This is true for arteries and veins of various sizes under either static or pulsatile pressure. In addition, vessel dimensions, initial curvature, stenosis, aneurysm, surrounding tissue support, and other geometric and material irregularities, as well as vessel growth, affect the critical buckling load. We further demonstrated that arteries and veins will twist-buckle and form a kink when twisting along their axes. The critical buckling torque increases with increasing lumen pressure and axial stretch ratio. We also established model equations that accurately predicted the critical buckling loads. Intellectual Merits: These results enrich and broaden the knowledge of vascular biomechanics and shed light on the biomechanical mechanism of artery tortuosity. The new knowledge sets a biomechanical basis for determining the appropriate axial tension in bypass grafting and reconstructive vascular surgery and for developing new techniques to prevent and treat vessel tortuosity by targeting mechanical factors that ultimately will improve the prevention and treatment of cardiovascular disease. Broader Impacts: The mechanical stability of living tissues and organs is important for their normal functioning. The biomechanics of artery buckling developed in this project has wide applications in vascular biology, pathophysiology, and surgery. The biomechanical model developed and the approach used can be useful for studying the stability and buckling of other biological organs and organelles and soft engineering structures. The research activities were integrated with the biomedical education at UTSA, with an emphasis on minority student education and training. The new findings from this project were incorporated into two bioengineering courses that enhance the biomedical engineering curriculum. The project also provided training opportunities for over 30 trainees, with most trainees of underrepresented backgrounds, including four postdoctoral fellows, 10 graduate students, 12 undergraduate students, and six high school students. This project also provided more training opportunities for minority students in other Minority Biomedical Research Support programs at UTSA, such as MARC-U*STAR, RISE, and LSAMP programs, to enhance biomedical education at this Hispanic-Serving Institution. These research and training activities attracted more minority students into the biomedical engineering field and contributed to the education of a diverse workforce in biomedical engineering. Our research activities were also featured in local news and internet media that raised the public awareness to the biomedical engineering research. In addition, this project has helped the investigator launch a successful academic career.

Project Start
Project End
Budget Start
2007-03-01
Budget End
2013-02-28
Support Year
Fiscal Year
2006
Total Cost
$478,000
Indirect Cost
Name
University of Texas at San Antonio
Department
Type
DUNS #
City
San Antonio
State
TX
Country
United States
Zip Code
78249