The right atrium is one of four chambers of the heart. There are two atria in the heart, the right and the left atrium, which are not communicated with one another. The right atrium gets deoxygenated blood from the superior and inferior vena cava, pumping it into the right ventricle through the tricuspid valve. The right auricular appendix is attached to it.
In the walls of the right atrium, next to the entrance of the superior vena cava, is the sinoatrial node, whose cells generates electrical impulses that begin the cardiac contractions. The right atrium is irrigated by the right coronary artery.