Right atrioventricular orifice

Right atrioventricular orifice
Section of the heart showing the ventricular septum. (Right atrioventricular orifice visible at left, but not labeled.)
Details
Identifiers
Latin	ostium atrioventriculare dextrum
Dorlands /Elsevier	o_09/12601882
TA	A12.1.02.002
FMA	9274
Anatomical terminology []

The right atrioventricular orifice (right atrioventricular opening) is the large oval aperture of communication between the right atrium and ventricle.

Situated at the base of the atrium, it measures about 4 cm. in diameter and is surrounded by a fibrous ring, covered by the lining membrane of the heart; it is considerably larger than the corresponding aperture on the left side, being sufficient to admit the ends of four fingers.

It is guarded by the tricuspid valve.

This article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)