Criss-Cross Heart

Hearts with twisted or “criss-cross” atrioventricular connections have spiraling pathways connecting each atrium to its draining ventricle. Frequently, this results in the interventricular septum lying horizontally with superior-inferior positioning of the ventricles. The atrioventricular and ventriculoarterial connections can be either concordant or discordant. The physiology of infants and children with this congenital heart malformation is determined by the presence of associated septal defects, ventricular hypoplasia, atrioventricular valve straddle, and degree of outflow tract obstruction. These features will result either in symptoms of cyanosis in the newborn period, or intracardiac mixing and shunt physiology later in childhood. The diagnostic challenge of criss-cross hearts is to correctly identify the loss of usual axial alignment between the atria and ventricles and to accurately assess the potential for re-septation without compromising ventricular capacity or atrioventricular valve function, while also achieving adequate pulmonary and systemic blood flow. A wide variety of surgical approaches are possible in these patients; their suitability is best assessed using multimodality imaging including three-dimensional reconstruction of the key intracardiac structures and anatomic relations.