Isolated pericardial effusion: an indication for fetal karyotyping?

The outcome and associations of 35 consecutive cases of isolated pericardial effusion detected in the fetus are presented. In all cases included in the study, there was no evidence of a structural abnormality or a rhythm disturbance detectable antenatally. Karyotyping revealed that 26% of cases had trisomy 21 and 31% of the total had some form of chromosomal anomaly. Our study shows that the outlook for isolated pericardial effusion is good. However, there is a high incidence of associated karyotypic anomalies, in particular trisomy 21. Fetal karyotyping is therefore recommended in these cases.