Colour Doppler myocardial imaging: potential applications in acquired and congenital heart disease

Doppler myocardial imaging (DMI) is a new ultrasound technique which has been developed to allow colour Doppler imaging of cardiac structures as opposed to blood pool imaging. This is achieved by changing the velocity, filtering and threshold parameters of the standard colour Doppler algorithms. DMI parameters which can be measured are regional tissue velocity, acceleration and reflected Doppler energy. In addition, concomitant changes in the pulsed Doppler algorithms allow interrogation of instantaneous peak velocities during the cardiac cycle in the myocardial region in which the sample volume is placed. In both adult acquired heart disease and congenital heart disease, these new ultrasound parameters may provide new information on myocardial contractile function, diastolic function, myocardial perfusion and myocardial structure. The relative lack of image quality by chest wall attenuation inherent in the Doppler technique means that the methodology is potentially superior to standard grey-scale two-dimensional imaging in boundary detection and may prove to be of value in providing a robust boundary detection algorithm for use in volume calculations and in three-dimensional reconstruction of ventricular function.