Physiologic Cardiovascular Strain and Intrinsic Wave Imaging

Abstract

Cardiovascular disease remains the primary killer worldwide. The heart, essentially an electrically driven mechanical pump, alters its mechanical and electrical properties to compensate for loss of normal mechanical and electrical function. The same adjustment also is performed in the vessels, which constantly adapt their properties to accommodate mechanical and geometrical changes related to aging or disease. Real-time, quantitative assessment of cardiac contractility, conduction, and vascular function before the specialist can visually detect it could be feasible. This new physiologic data could open up interactive therapy regimens that are currently not considered. The eventual goal of this technology is to provide a specific method for estimating the position and severity of contraction defects in cardiac infarcts or angina. This would improve care and outcomes as well as detect stiffness changes and overcome the current global measurement limitations in the progression of vascular disease, at little more cost or risk than that of a clinical ultrasound.

Ultrasonic characterization of the nonlinear properties of canine livers by measuring shear wave speed and axial strain with increasing portal venous pressure

“…These parameters are consistent with the kernel sizes and dimensions previously reported for strain imaging in 2-D (Konofagou et al, 2011; Korukonda and Doyley, 2011; Wang et al, 2008) and 3-D displacement estimation (Byram et al, 2010; Kuo and von Ramm, 2008). …”

Acoustic Waves in Medical Imaging and Diagnostics

“…Kanai has made measurements of the waves present in the heart as it beats (Kanai 2005; Kanai 2009). A method called electromechanical imaging has been used to measure the electromechanical waves propagating in the heart wall and the pulse waves propagating in the arterial vasculature (Pernot et al 2007; Wang et al 2008; Vappou et al 2010; Konofagou et al 2011; Provost et al 2011). A method that uses passive tomography methods, adapted from the field of seismology, has been reported that uses physiological motion to measure the shear wave velocity in various soft tissues (Benech et al 2009; Gallot et al 2011).…”

Radial Basis Functions for Combining Shape and Speckle Tracking in 4D Echocardiography

“…Lee et al have shown that RF-based speckle tracking provides accurate strain measurements when compared to tagged MR in 2D myocardial slices [12], [13]. They went on to show that 2D RF-based speckle tracking could be used to identify regions of abnormal cardiac function [14]. …”