[Fetal and neonatal supraventricular paroxysmal tachycardias]

The authors report 3 cases of fetal supraventricular tachycardia which carried on into neo-natal life. In one case the tachycardia was discovered in the 35th week of amenorrhoea and was able to be followed up to term. In this respect the means of making a definite diagnosis are as follows : a cardiotocogram when one happens to be able to observe the beginning or the end of an attack (in which case a definite "plateau" shape is found) and especially a fetal electrocardiogram obtained transparietally in pregnancy or by means of an internal electrode in labour. Supraventricular tachycardia is usually of marked degree and comes in isolated episodes and is not to be confused with tachycardia that is found accompanying fetal distress, occurring in pathological pregnancies. The obstetrician can therefore delay while carrying out intensive supervision of the case, which is particularly directed to searching for signs of generalised feto-placental oedema. After birth the child should be transferred to an intensive care unit where the tachycardia, if it persists, should be reduced in order to avoid serious asystolies. The outlook for the baby if there is no congenital malformation is good, since the trouble with the cardiac rhythm is usually a reflection of lack of maturity in the cardiac conduction tissues.