[Tissue Doppler imaging of the fetal heart--a new parametric ultrasound technique in prenatal medicine].

Tissue Doppler imaging is a new ultrasound technique for the acquisition and analysis of myocardial velocity and deforming parameters in the human heart. In cardiology this innovative technique is used to identify ischemic regions and stunned areas after cardiac infarction and to diagnose dyssynchrony. In the last two years, our research group has been using this technique extensively on fetal hearts. It is possible to establish the fetal cardiac cycle clearly just by analyzing the typical courses of myocardial velocity curves. The quality of the curves is comparable to the results in adult cardiology. Consequently, many innovative analysis options can be acquired, e.g., the comparison of the kinetics of several myocardial regions in the cardiac cycle, the determination of pre- and post-systolic intervals (isovolumic contraction time, isovolumic relaxation time), the evaluation of diastolic function by analyzing the E(m) and A(m) waves and the detection of the atrial contraction. These parameters are currently used in cardiology for extended function analysis. Tissue Doppler imaging is the first step in parametric imaging of the fetal heart and consequently marks the beginning of a new era in fetal echocardiography.