Background: Sustained fetal tachyarrhythmia may result in congestive heart failure, hydrops fetalis, and fetal/neonatal death, which requires timely and appropriate therapy.
Aim: To determine the value of transplacental digoxin therapy for fetal tachyarrhythmia with multiple evaluations.
Methods: Four cases of fetal tachyarrhythmia were diagnosed with fetal echocardiography and treated with transplacental digoxin therapy with an initial dosage of 0.25 mg qd. Fetal echocardiography and measurement of maternal serum digoxin concentrations were performed every 5-7 days. Echocardiographic information was further used for the calculation of three evaluation systems including, Tei index, cardiovascular profile score (CVPS), and umbilical artery resistance index (UARI). The dosage of digoxin was adjusted according to the serum concentration, as well as results from three evaluation systems.
Results: During the course of digoxin treatment, our patients show an increase of CVPS and decrease of Tei index and UARI, suggesting the recovery of heart function. Sinus rhythm was restored in 3-10 days in three cases and 42 days in one case. At the time of delivery, the placental transportation efficiency (neonate/mother ratio of serum digoxin concentration) was 76.45-84.31%. Following delivery, the general conditions of neonates were favorable. During the 4- to 14-month follow-up, reoccurrence of arrhythmia, neurological deficit, and retarded growth and development were not observed.
Conclusions: Transplacental digoxin therapy with combined evaluation of Tei index, CVPS, and UARI systems is useful for treating fetal atrial flutter (AF) and supraventricular tachycardia (SVT).