An Ultrasound-Driven Kinematic Model of the Heart That Enforces Local Incompressibility

摘要

Local incompressibility can be used to improve fitting and analysis of ultrasound-based displacement data using a heart model. An analytic mathematical model incorporating inflation, torsion, and axial extension was generalized for the left ventricle. Short-axis and long-axis images of mouse left ventricles were acquired using high frequency B-mode ultrasound and myocardial displacements were determined using speckle tracking. Deformation gradient components in the circumferential and longitudinal directions were fitted using linear regressions. The slopes of these lines were then used to predict motion in the radial directions. The optimized kinematic model accurately predicted the motion of mouse left ventricle during rilling with normalized root mean square error of 4.4±1.2%.