[Determination of systolic time intervals of the fetal heart as an additional diagnosis sub partu].

The aim was to prove the usefulness of the determination of systolic time intervals PEP (pre-ejection period) and LVET (left ventricular ejection time) in the fetal cardiac cycle.--Based on the fetal electrocardiogram a second signal is necessary to get the corresponding times. In the own material we used the fetal phonocardiogram. Therefore we measured the times of Q-S1 and Q-S2. As a particularly important factor seems to be the quotient of PEP/LVET. The normal result of this quotient was 0.39 +/- 0.04 (0.35-0.43). In pathological cases the quotient was only 0.27 +/- 0.02 (0.25-0.29). These results are compared with the literature. Here are problems, because various investigators use various methods for getting the second signal (phonocardiogram, doppler ultrasonic cardiogram or fetal capillary pulse). Nevertheless determination of the fetal systolic time intervals is necessary, because many parameters are required to have an overview about the fetal condition.