Juxtaposition of the Atrial Appendages
Juxtaposition of the atrial appendages refers to that condition in which both atrial appendages or one and part of the other lie beside each other and to one side of the great arterial vessels. The appendages lying to the left of the great vessels (left-sided juxtaposition) is considerably more common than the state in which the appendages lie to the right of the great vessels (right-sided juxtaposition) by a ratio of about 6:1. Among left-sided juxtaposition it is common that the right atrial appendage be bifid and that only its left unit be "juxtaposed." Such a state is termed "bifid atrial appendage with partial juxtaposition." Juxtaposition almost always is associated with significant congenital heart disease in which transposition of the great vessels is commonly a feature. Tricuspid atresia with transposition or complete transposition are the two conditions most commonly associated with juxtaposition. Recognition of juxtaposition as an entity may serve, under certain circumstances, as an aid in the evaluation of an angio-cardiogram.
- © 1973 American Heart Association, Inc.