Antenatal diagnosis
Tetralogy of Fallot can be diagnosed antenatally as early as
12 weeks of gestation [22]. In a population-based study,
however, only half of the cases were detected during routine
obstetric ultrasonic screening [23]. In general,
patients who are referred for foetal echocardiography with
a suspicion of tetralogy of Fallot have the most severe phenotypes
[23]. Other reasons for referral for foetal echocardiography
include discovery of extra-cardiac
malformations, or known chromosomal abnormalities.
As a result, patients referred for foetal echocardiography
tend to have worse outcomes when compared to patients
who are diagnosed postnatally [23]. The foetus with
tetralogy can be delivered vaginally, but efforts should be
made for delivery to occur in a centre where paediatric cardiologists
are available to aid in the postnatal care.