Perinatal outcomes of intrauterine fetal arrhythmias: A 10-year retrospective cohort study

Sustained fetal arrhythmia can produce life-threatening fetal distress, fetal hemodynamic compromise, hydrops fetalis, or even fetal death. Survivors may subsequently possess severe neurologic deficits. We conducted a retrospective observational study of pregnant women hospitalized with fetal arrhythmias from January 2011 to May 2020 at West China Second University Hospital, and fetal arrhythmias were diagnosed by specialists in cardiac ultrasonography. Of 90 cases of fetal arrhythmias, 14 (15.6%) were complicated by fetal congenital heart disease (CHD), 21 (23.33%) by fetal-hydrops, 15 (16.67%) cases by intrauterine therapy, and 6 (6.67%) by maternal auto-immune disease. In the fetal-hydrops group, the intrauterine therapy rate was significantly higher (47.62% vs 7.24%, P < .001) and the survival rate significantly lower (47.62% vs 92.75%, P < .001) than in the nonfetal hydrops group. A fetus whose arrhythmia was complicated by fetal-hydrops and CHD was delivered earlier and exhibited a lower cardiovascular profile score at diagnosis and birth, lower birth weight, and a higher rate of pregnancy termination than cases without hydrops and CHD (P < .05). Among the cases with maternal auto-immune disease, 71.43% (5/7) manifested fetal atrioventricular block. Multiple linear regression analysis revealed that 3 variables – fetal-hydrops (P < .001), body mass index (P = .014), and gestational age at diagnosis of fetal arrhythmia (P = .047) – were correlated with the gestational delivery age of arrhythmic fetuses. Parents should be counseled by the multidisciplinary team regarding the individualized management and prognosis of the arrhythmic fetus, and individualized fetal intrauterine therapy should be performed if necessary.