Objective: To describe the prenatal sonographic appearances in cases of absent pulmonary valve syndrome and the importance of investigating the presence of 22q11 deletion.
Methods: We describe 2 cases, which were referred because of a suspicion of a cardiac malformation. In both cases, a large anechoic mass emerging from the right ventricle was visualized and identified as an aneurysmal dilatation of the pulmonary trunk with hypertrophy of the right ventricle. The diagnosis of tetralogy of Fallot with absent pulmonary valve syndrome and a secondary diverticular dilatation of the pulmonary artery was made. A review of the literature revealed another 18 cases of prenatal diagnosis of absent pulmonary valve syndrome with or without knowledge of chromosomal abnormalities.
Results: Pathologic examinations confirmed the diagnosis of absent pulmonary valve syndrome in both cases. Final results of fetal karyotyping revealed a 22q11 deletion in the first case.
Conclusions: An abnormal 4-chamber view with an aneurysmal dilatation of the pulmonary trunk should suggest the diagnosis of this rare congenital anomaly. Perinatal death occurs in more than 60% of cases and is usually associated with hydrops fetalis, the presence of other malformations, or both. Even in the absence of extracardiac malformations, investigation for 22q11 deletion in cases of conotruncal cardiac abnormalities is recommended.