Criss-cross heart--a case with horizontal septum, complete transposition, pulmonary atresia and ventricular septal defect.

Criss-cross heart is a recently described anomaly in which the systemic and pulmonary blood streams cross at the atrioventricular (AV) level, without mixing. A case of criss-cross heart is described in which the right atrium, in a solitus position, communicated with a left-superior positioned, morphologically right ventricle, and the left atrium communicated with a normally located, morphologically left ventricle. The interventricular septum occupied a horizontal plane. Associated defects were complete d-transposition of the great arteries with l-positioned aorta, pulmonary atresia, ventricular septal defect, atrial septal defect, and patent ductus arteriosus. To the best of our knowledge this is the first angiocardiographic demonstration of this rare combination of lesions. The literature on criss-cross heart and horizontal septum is reviewed. It is stressed that regardless of whether the criss-cross phenomenon is an anatomical fact or an angiocardiographic illusion, it is an established angiocardiographic entity and should be recognized as such.