Medicine and Health related Information

The two parts of the right atrium develops from two diffrent sources.
a) The anterior rough muscular part of right atrium and right auricle develops from right half of atrial chamber.
b) The posterior smooth part of atrium develops from the right horn of sinus venosus. The tributaries of sinus venosus also open into the posterior smooth part of right atrium. This part of right atrium is called sinus venosum.
c) The right and left valve of sini-atrial orifice fuses at its upper end and forms spetum spurium.
d) The septum spurium and left valve fuses with the interatrial septum.
e) The right valve divides into 3 parts by 2 limbic bands and gives rise to terminalis, valve of inferior venacava, valve of coronary sinus.