Major congenital heart disease: antenatal detection, patient characteristics and outcomes

Objective
To determine the antenatal detection rate in Northern Ireland (NI) for major congenital heart disease (CHD) between 1st January 2002 and 31st December 2006. To compare characteristics and prognosis of antenatal versus postnatal groups.

Methods
Data were obtained from fetal, neonatal and post-mortem records. Variables recorded: antenatal diagnosis, karyotype, referral indication, type of defect and neonatal outcome.

Results
Twenty-seven per cent (73/272) of patients with major CHD were diagnosed antenatally. Forty-one per cent (30/73) of these died before 28 days. Eighty-two per cent (60/73) of the antenatal diagnosis group were referred with suspected cardiac abnormality on obstetric screening. There were more lethal trisomies amongst the antenatal diagnosis group (15%, 11/73) than the postnatal diagnosis group (2%, 4/191) p < 0.001. Significantly more of the antenatal group had functionally univentricular hearts than the postnatal/post-mortem group (47%vs. 7%). Eighty-nine per cent (65/73) of defects diagnosed antenatally were ‘four chamber view’ defects. 11% (8/73) were ‘outflow tract view’ defects.

Conclusions
Antenatal detection in NI is around the European average. Those with an antenatal diagnosis have more complex CHD, higher risk of karyotype abnormality and poorer neonatal outcomes. Screening is responsible for the majority of antenatal diagnoses of major CHD. A regional training programme for obstetric sonographers has now been delivered.