Prenatal diagnosis, management and outcome of fetal dysrhythmia: a tertiary fetal medicine centre experience over an eight-year period.

OBJECTIVE

To review the prenatal diagnosis, management and outcome of fetal dysrhythmia.

METHODS

Prenatal diagnosis, management and outcomes of fetuses with dysrhythmia were reviewed retrospectively (01/01/1997 to 31/12/2004).

RESULTS

Over an 8-year period, 318 pregnant mothers were referred for assessment of suspected fetal dysrhythmias. Median gestation was 30 weeks (range 19-41). Fetal dysrhythmia was identified in 182 (57%) and classified as: (i) 126 atrial extrasystoles; (ii) 26 tachyarrhythmia, and (iii) 30 bradyarrhythmia. Of the fetuses with tachyarrhythmia, 23 had supraventricular tachycardia (SVT), 2 atrial flutter and 1 sinus tachycardia. One death associated with severe hydrops occurred in the tachyarrhythmia group. 19 cases of SVT were successfully treated in utero. Both cases of atrial flutter required direct current cardioversion in the neonatal period. In the bradyarrhythmia group, there were 15 isolated cases and 10 cases associated with congenital heart disease, with 73 and 20% survival, respectively.

CONCLUSIONS

Benign atrial extrasystoles are the commonest cause for referral and assessment of fetal dysrhythmia. The overall prognosis for SVT is good with the majority responding to transplacental therapy. In cases with congenital atrioventricular block, the outcome was less favourable, especially when the atrioventricular block was associated with congenital heart disease.