Cardiac anatomy from right to left

Right atrium

The cardiac anatomy will be discussed in the order of normal blood flow: from the right to the left.
In the normal situation, contrast will be injected intravenously - usually in the arm - reaching the right atrium via the superior vena cava.
The right atrium has an anterolateral position in the heart, and lies inferior to the left atrium.
The superior vena cava enters through the roof of the right atrium.
The inferior vena cava enters the right atrium from below near the cardiac septum.
Another structure that carries blood towards the right atrium is the coronary sinus, (venous return of the coronaries) which enters anterior to, and just to the left of the inferior vena cava.

Axial (left) and coronal oblique (right) reconstructions of the heart, depicting the right atrium and its main contributing blood vessels: the coronary sinus (blue arrow) and superior and inferior vena cava. IVC=inferior vena cava, A=anterior, SVC=superior vena cava