Shear wave tracking: open chest versus closed chest

This paper describes an in-vivo pilot study in which the systolic myocardial stiffness of four pigs was measured with various acoustic techniques. We compare the propagation velocity of shear waves in open chest and closed chest experiments, in which the open-chest shear wave was either physiologically induced by aortic valve closure (N=3), or externally induced by acoustic-radiation force (N=1). The results of closed-chest versus open-chest recordings are consistent within 1 unit of standard error, whereas the acoustic-radiation force measurement showed lowest standard deviation (7% versus 13%).