Criss-cross heart: report of three cases with double-inlet ventricles diagnosed in utero.

Criss-cross heart is a rare congenital cardiac anomaly characterized by crossing of the inflow streams of the two ventricles, due to an apparent twisting of the heart about its long axis and when the axes of the openings of the atrioventricular (AV) valves are not parallel. If unrecognized, this leads to incorrect sequential segmental analysis. We report three cases of double-inlet ventricle with a criss-cross spatial relationship of the AV valves detected on prenatal ultrasound examination at 19-23 weeks' gestation. The sequential diagnosis was confirmed at postmortem examination in two cases and by neonatal echocardiography in the other. Antenatal diagnosis of criss-cross effect of the AV valves is feasible, allowing correct fetal diagnosis and appropriate counseling for this rare form of congenital cardiac disease.