The Electronic Evaluation of Fetal Heart Rate

Abstract

Twenty-five cases of fetal cardiac arrhythmia caused by premature and missed beats have been presented. Of the 25 arrhythmias, 23 were of supraventricular origin and 2 of ventricular origin. In 22 cases the arrhythmia disappeared almost immediately after birth, and in 2 it persisted as long as 48 hours. The remaining record was taken from an immature fetus whose umbilical cord had prolapsed. This fetus died during labor. In spite of a frequent clinical diagnosis of "fetal distress" in this type of arrhythmia, all but the immature fetus were delivered in good condition. The recorded data suggest that these arrhythmias may be caused by vagotonia (associated with possible mild hypoxia) and not by anoxic myocardial irritability.