[Microdeletion of 22q11 and conotruncal cardiopathies: contribution of prenatal diagnosis]

Abstract

Objective: We report our experience on prenatal diagnosis of 22q11 deletion by fluorescent in situ hybridation (FISH).

Patients and methods: From February 1997 to April 1998, prenatal diagnosis of 22q11 deletion was performed in 13 cases of congenital conotruncal heart defects. FISH was carried out using D22S75 DiGeorge's chromosome region probe.

Results: Microdeletions of 22q11 were detected in 4 fetuses with tetralogy of Fallot (3 cases) and pulmonary atresia with ventricular septal defect (1 case). Termination of pregnancy was performed in two cases for severe congenital heart defect. A third malformed fetus died immediately after a blood sampling procedure. The last fetus, with a tetralogy of Fallot malformation, was born and underwent corrective cardiac surgery. The dysmorphic features of this fetus was suggestive of DiGeorge's syndrome, and the development status was normal.

Conclusion: Prenatal detection of 22q11 only played a minor role in the decision to terminate the pregnancy in our study.