Objective
To compare outcomes and characteristics of patients with antenatally diagnosed major congenital heart disease (CHD) with postnatally diagnosed cases. Northern Ireland has 22 000 live births per year. There is a low termination rate; providing the opportunity to study the natural history of fetal CHD.
Methods
Patients born between 1/1/3 and 31/12/8 were included. Cases were identified using the regional fetal and paediatric cardiology database and post-mortem records. Data recorded includes – outcome (termination of pregnancy, intra-uterine death, neonatal death, neonatal survival), karyotype and physiology (uni- or bi-ventricular).
Results
31% (108/346) of major CHD was diagnosed antenatally. Of the antenatal diagnoses, 80% (86) were live born, 12% (13) died in-utero and 8% (9) pregnancies were terminated. 22% (19) of antenatally diagnosed live births died during the neonatal period. 62% (67/108) reached 28 days, compared with 93% of the postnatal group (221/238, p<0.0001). There was no significant difference in the proportion of karyotype defects in the antenatal group (25%, 27/108) versus the postnatal group (23%, 54/238, p=0.64). Excluding lethal karyotypes (trisomy 13 and trisomy 18), mortality for livebirths was not significantly different (12%, 9/75 vs 7%, 15/229, p = 0.13). 46% (50/108) of the antenatal group had functionally univentricular physiology, compared with 8% (18/238) of the postnatal group (p<0.001).
Conclusions
Antenatally diagnosed cases have significantly higher early mortality than those with a postnatal diagnosis. However, the mortality difference is negligible for liveborn infants without lethal trisomies. This is despite the significantly higher proportion of these cases having functionally uni-ventricular physiology.