Diagnostic and perinatal management of fetal extrasystole

Fifty fetuses referred to the Polish Mother's Memorial Hospital for fetal echocardiography between January 1, 1991 and June 1, 1995 were evaluated. The mean fetal gestational age at the time of diagnosis of arrhythmia was 34.1 weeks, and the mean gestational age at the time of delivery was 38.7 weeks. Checkup echocardiographic examinations were performed every 10-14 days, for a mean 2.4 studies per fetus. In most cases (48/50, 96%), premature atrial contractions were present during the first echocardiography examination. The fetal heart study was normal in 30 cases; in 7 (14%) there was tricuspid valve regurgitation, in 7 (14%) an atrial septal aneurysm, in 4 congenital heart defects, in 1 myocardial hypertrophy, and in 1 disproportion in the four-chamber view. Of the 50 fetuses, 43 underwent regular echocardiographic monitoring alone; in 7 cases, based on the presence of additional echocardiographic findings, pharmacotherapy was applied (digoxin, verapamil, or both). Three neonates died after delivery owing to malformations in two cases (one critical aortic stenosis, one spina bifida plus hygroma colli) and due to myocarditis in one case. In six of seven newborns treated in utero, myocarditis was diagnosed after birth (including the one with neonatal demise). Most of the newborns were in good condition after birth, their mean Apgar score being 8.6 and the mean birth weight 3259 g. We concluded that most extrasystoles represent an isolated anomaly, not affecting the fetal condition. Their presence should not influence the obstetric care and may require only echocardiographic monitoring. In most of our cases the premature contractions subsided after birth, although sometimes they preceded fetal supraventricular tachycardia or appeared after congenital myocarditis.