Prenatal diagnosis, associated findings and postnatal outcome in fetuses with congenitally corrected transposition of the great arteries

PURPOSE: To analyze anatomic features and associated malformations in 37 prenatally detected cases of congenitally corrected transposition of the great arteries (ccTGA) and to evaluate the prenatal course, neonatal outcome and mid-term follow-up. METHODS: Retrospective analysis of prenatal ultrasound of 37 patients with ccTGA in two tertiary centers between 1999 and 2019. All fetuses received fetal echocardiography and a detailed anomaly scan. Postnatal outcome and follow-up data were retrieved from pediatric reports. RESULTS: Isolated ccTGA without associated cardiac anomalies was found in 13.5% (5/37), in all other fetuses additional defects such as VSD (73.0%), pulmonary obstruction (35.1%), tricuspid valve anomalies (18.9%), aortic arch anomalies (13.5%), ventricular hypoplasia (5.4%) or atrioventricular block (5.4%) were present. The rate of extracardiac malformations or chromosomal aberrations was low. There were 91.9% (34/37) live births and postnatal survival rates reached 91.2% in a mean follow-up time of 4.98 years. The prenatal diagnosis of ccTGA was confirmed postnatally in all but one documented live birth and the prenatal counselling regarding the expected treatment after birth (uni- versus biventricular repair) was reassured in the majority of cases. The postnatal intervention rate was high, 64.7% (22/34) received surgery, the intervention-free survival was 36.7%, 35.0% and 25.0% at 1 month, 1 year and 10 years, respectively. CONCLUSIONS: ccTGA is a rare heart defect often associated with additional heterogeneous cardiac anomalies that can be diagnosed prenatally. The presented study demonstrates a favorable outcome in most cases but the majority of patients require surgical treatment early in life.