Direct Intrauterine Fetal Treatment of Fetal Tachyarrhythmia with Severe Hydrops fetalis by Antiarrhythmic Drugs

Abstract

In cases of non-immune hydrops fetalis caused by tachyarrhythmias, the transplacental passage of antiarrhythmic drugs may be hampered. When this is proven by fetal blood sampling in cases of tachyarrhythmia refractory to transplacental treatment, additional administration of antiarrhythmic drugs into the fetus is necessary and seems to improve the results. Although injections of antiarrhythmic agents in fetal ascites are also highly effective, intravascular administration by sonographic guidance is to be preferred. Then, simultaneous measurements of fetal and maternal drug levels are possible for the evaluation of pharmacokinetics and for monitoring the antiarrhythmic therapy.

New Therapeutic Aspects in Nonimmune Hydrops fetalis Based on Four Hundred and Two Prenatally Diagnosed Cases

“…By repeated fetal blood samplings, an im paired transplacental passage of the antiar rhythmic agents was proved in our cases with severe NIHF [8]. In 11 cases a congeni tal heart block was present, associated with structural cardiac defects in all cases.…”

“…Causes and associations, gestational age of diagnosis and outcome of pregnancies of the 402 cases are summarized in figure 1 In addition to the more often described transplacental ther apy, in our population direct applications of antiarrhythmic drugs were performed in 10 of these 21 cases, in some individuals by repeated injection of drugs into fetal ascites and more recently in the umbilical vein [8].…”

“…Direct applications of antiarrhythmic drugs can be necessary in fetuses with severe NIHF caused by tachyarrhyth mia when impaired transplacental passage of antiarrhythmic drugs is proved by fetal blood sampling [8]. In this way, cases of tachyarrhythmia and NIHF refractory to transplacental therapy can be treated suc cessfully in utero [8].…”

Quantitative Analysis of Cardiac Function in Non-Immunological Hydrops fetalis

“…Individual therapeutic management of non-immunological hydrops fetalis has been discussed in recent years [1,2], The treat ment of in utero congestive heart failure in cases of cardiogenic hydrops fetalis is now starting [3,4]. Using color flow mapping, we reported on the successful diagnosis of fetal heart disease [5].…”

Successful Treatment of Supraventricular Tachycardia with Flecainide Acetate: A Case Report

“…Not every fetus will benefit from transplacental therapy, and direct fetal treatment [3] may be necessary to overcome failure of oral therapy or the obvious circulatory insufficiency of the hydropic fetus. However, problems to date have been the short half-life of drugs and the consequent need for a repeat invasive procedure.…”