The sinus venarum (also known as the sinus of the vena cava, or sinus venarum cavarum
) is the portion of the
right atrium
The atrium ( la, ātrium, , entry hall) is one of two upper chambers in the heart that receives blood from the circulatory system. The blood in the atria is pumped into the heart ventricles through the atrioventricular valves.
There are two atr ...
in the adult human heart
where the inner surface
of the right atrium is smooth.
The sinus venarum represents the portion of the adult heart that develops from the
right sinus horn of the
foetal
sinus venosus
The sinus venosus is a large quadrangular cavity which precedes the atrium on the venous side of the chordate heart. In mammals, it exists distinctly only in the embryonic heart, where it is found between the two venae cavae. However, the sinus ve ...
.
The sinus venarum is demarcated from the rest of the (rough
trabeculated
) inner surface of the
right atrium
The atrium ( la, ātrium, , entry hall) is one of two upper chambers in the heart that receives blood from the circulatory system. The blood in the atria is pumped into the heart ventricles through the atrioventricular valves.
There are two atr ...
by the
crista terminalis
The crista terminalis or terminal crest represents the junction between the sinus venosus and the heart in the developing embryo. In the development of the human heart, the right horn and transverse portion of the sinus venosus ultimately become in ...
.
References
{{Portal bar, Anatomy
Cardiac anatomy