Doppler myocardial imaging. A new tool to assess regional inhomogeneity in cardiac function

In echocardiography, there is still a need for a better tool to quantify regional myocardial function. Doppler myocardial imaging (DMI) allows the calculation of local myocardial velocity profiles for segmental motion in both the radial and longitudinal direction. From the local velocity profile data, 1-dimensional regional myocardial strain rates (SR) and strain (epsilon) can now be calculated. These new deformation indices more accurately define regional function compared to velocities as they are independent of overall heart motion. This paper will define the normal segmental velocity, SR and epsilon profiles and their relationship with global mechanical event markers. It will also define the changes in local velocity and deformation characteristics, which are induced by disease and the current experimental and clinical status of this new quantitative ultrasound tool.