cor triatriatum

(redirected from accessory atrium)

cor tri·at·ri·a·'tum

a heart with three atrial chambers, the left atrium being subdivided by a transverse septum with a single small opening that separates the openings of the pulmonary veins from the mitral valve.
Synonym(s): accessory atrium

cor triatriatum

[kôr trī·ā′trē·ā′tum]
a congenital anomaly caused by failure of resorption of the embryonic common pulmonary vein, resulting in division of the left atrium by a fibromuscular diaphragm, the posterosuperior chamber receiving the pulmonary venous return and the anteroinferior chamber communicating with the left atrial appendage and mitral orifice. The orifice between the two compartments may be reduced or absent, producing pulmonary venous obstruction.

cor tri·at·ri·a·tum

(kōr trī-at-rī-ā'tŭm)
A congenital anomaly characterized by a heart with three atrial chambers, the left atrium being subdivided by a transverse septum with a single small opening that separates the openings of the pulmonary veins from the mitral valve.