Transplacental fetal therapy for junctional ectopic tachycardia.

Junctional ectopic tachycardia (JET) is a rare type of tachyarrhythmia. A 39-year-old woman was transferred to our hospital for fetal tachyarrhythmia at 32 weeks' gestation. Fetal cardiac sonography revealed atrial and ventricular rates of 120-130 and 175-230 bpm, respectively, without 1:1 atrioventricular relationship. As ventricular tachycardia was considered to be the most probable diagnosis, transplacental therapy with digoxin and sotalol was done with partial response. Diagnosis of JET was made after birth. Although fetal JET is rare and prenatal diagnosis and treatment of this condition is still a challenge, differential diagnosis of fetal tachyarrhythmia should include this disorder.