Craig Simmons

University of Toronto, Dept. of Mechanical & Industrial Engineering

Canada Research Chair in Mechanobiology




The valves in your heart snap open and close with every heartbeat,
subjecting the cells in the valve leaflets to extreme pressures,
deformations, and shear stresses as blood rushes by them. Remarkably
most valves will last a lifetime in the face of these repeated
biomechanical insults. But when valve failure does occur, it has dire
consequences and the valve must be replaced surgically, as there is no
drug treatment for heart valve disease. Notably, the most common valve
disease involves scarring and calcification of the leaflets in focal
regions in which the tissue is inherently stiffer and the cells are
exposed to disturbed blood flow patterns. These spatial correlations
between the biophysical microenvironment and sites of disease
development may provide clues as to the factors that contribute to valve
homeostasis and disease, ultimately revealing therapeutic targets. In
this talk, I will present our work aimed at identifying the
biomechanical regulators of valve (patho)biology, with particular focus
on how hemodynamics and extracellular matrix stiffness may modulate
valve cell dysfunction to contribute to aortic valve stenosis.