Comparison of impact of prenatal versus postnatal diagnosis of congenitally corrected transposition of the great arteries.

Congenitally corrected transposition of the great arteries (CCTGA) in the absence of major cardiac anomalies is thought to have a good outcome, although this has not been well documented. The objective of the present study was to compare the characteristics and outcomes of patients with a prenatal diagnosis of CCTGA to the characteristics and outcomes of those diagnosed postnatally. The optimal outcome was defined as intervention-free survival. All patients with CCTGA diagnosed prenatally and postnatally from 1999 to 2006 at 2 tertiary care institutions were reviewed. Patients with a single ventricle, heterotaxy, or valvar atresia were excluded. The differences between groups were assessed using the t test and chi-square test. A total of 54 patients (16 prenatal with 14 live born and 39 postnatal) were included. The patients diagnosed prenatally were diagnosed at a median gestational age of 20 weeks (range 16 to 37). Two deaths in each group were due to heart failure. The intervention-free survival rate for the prenatal and postnatal groups at 1, 6, and 36 months was 79%, 45%, and 30% and 85%, 61%, and 23%, respectively (p = NS). Of 37 patients, 14 (38%) underwent an arterial switch plus atrial baffling so that the morphologic left ventricle supported the systemic circulation, and 6 (16%) underwent repair of associated lesions so the morphologic right ventricle supported the systemic circulation; 4 (11%) of the 37 patients had pacemaker only. Prenatal patients with >1 fetal echocardiogram (12 of 14) did not have progression before birth. In conclusion, CCTGA has a >70% risk of intervention in the first 3 years after birth. The outlook is guarded and has an important effect on prenatal counseling.