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Annals of Biomedical Engineering

, Volume 41, Issue 7, pp 1331–1346 | Cite as

Aortic Valve: Mechanical Environment and Mechanobiology

  • Sivakkumar Arjunon
  • Swetha Rathan
  • Hanjoong Jo
  • Ajit P. YoganathanEmail author
Article

Abstract

The aortic valve (AV) experiences a complex mechanical environment, which includes tension, flexure, pressure, and shear stress forces due to blood flow during each cardiac cycle. This mechanical environment regulates AV tissue structure by constantly renewing and remodeling the phenotype. In vitro, ex vivo and in vivo studies have shown that pathological states such as hypertension and congenital defect like bicuspid AV (BAV) can potentially alter the AV’s mechanical environment, triggering a cascade of remodeling, inflammation, and calcification activities in AV tissue. Alteration in mechanical environment is first sensed by the endothelium, which in turn induces changes in the extracellular matrix, and triggers cell differentiation and activation. However, the molecular mechanism of this process is not understood very well. Understanding these mechanisms is critical for advancing the development of effective medical based therapies. Recently, there have been some interesting studies on characterizing the hemodynamics associated with AV, especially in pathologies like BAV, using different experimental and numerical methods. Here, we review the current knowledge of the local AV mechanical environment and its effect on valve biology, focusing on in vitro and ex vivo approaches.

Keywords

Aortic valve Mechanobiology Shear stress Pressure Stretch Bicuspid Calcification 

Notes

Acknowledgments

Authors wish to thank the Cardiovascular Fluid Mechanics Lab, Dr. Hanjoong Jo’s lab, Dr. Robert M. Nerem’s Lab members, and all other researchers for their contributions to the work presented in this paper. Authors also would like to thank all the relevant funding sources for the Cardiovascular Fluid Mechanics lab at Georgia Tech: American Heart Association under the Post-doctoral Research Awards (0625620B, 10POST3050054) and Pre-doctoral Research Award (09PRE2060605), National Science Foundation through the Engineering Research Center program at the Georgia Tech under the award EEC 9731643, National Heart, Lung and Blood Institute grant number HL-07262, the Wallace H. Coulter Distinguished Faculty Chair funds, Petit Undergraduate Research Scholars Program, a gift from Tom and Shirley Gurley, and all other sources. Finally, the authors acknowledge the kindness of Mr. Holifield for donating porcine heart valves, and thank the machine shop crew at School of Chemical and Biomolecular Engineering, Georgia Tech for machining the ex vivo bioreactors for some of the studies presented in this paper.

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Copyright information

© Biomedical Engineering Society 2013

Authors and Affiliations

  • Sivakkumar Arjunon
    • 1
  • Swetha Rathan
    • 2
  • Hanjoong Jo
    • 1
    • 3
  • Ajit P. Yoganathan
    • 1
    • 2
    Email author
  1. 1.The Wallace H. Coulter Department of Biomedical EngineeringGeorgia Institute of Technology and Emory UniversityAtlantaUSA
  2. 2.School of Chemical and Biomolecular EngineeringGeorgia Institute of TechnologyAtlantaUSA
  3. 3.Division of Cardiology, Department of MedicineEmory UniversityAtlantaUSA

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