where does right atrium pump blood when it contracts
venous circulation
title: Heart text: right atrium and the right ventricle, separated by a valve, the tricuspid valve. The right atrium receives blood almost continuously from the body's two major veins, the superior and inferior venae cavae. A small amount of blood from the coronary circulation also drains into the right atrium via the coronary sinus, which is immediately above and to the middle of the opening of the inferior vena cava. In the wall of the right atrium is an oval-shaped depression known as the fossa ovalis, which is a remnant of an opening in the fetal heart known as the foramen ovale. Most title: Atrium (heart) text: now used for an appendage of the atrium. Humans have a four-chambered heart consisting of the right atrium, left atrium, right ventricle, and left ventricle. The atria are the two upper chambers. The right atrium receives and holds deoxygenated blood from the superior vena cava, inferior vena cava, anterior cardiac veins and smallest cardiac veins and the coronary sinus, which it then sends down to the right ventricle (through the tricuspid valve) which in turn sends it to the pulmonary artery for pulmonary circulation. The left atrium receives the oxygenated blood from the left and right pulmonary veins, which it title: Atrium (heart) text: pumps to the left ventricle (through the mitral valve) for pumping out through the aorta for systemic circulation. The right atrium and right ventricle are often referred to as the "right heart" and similarly the left atrium and left ventricle are often referred to as the "left heart". The atria do not have valves at their inlets and as a result, a venous pulsation is normal and can be detected in the jugular vein as the jugular venous pressure. Internally, there are the rough pectinate muscles and crista terminalis of His, which act as a boundary inside the atrium and title: Heart text: role in cardiac conduction. It arises from the lower part of the interventricular septum and crosses the interior space of the right ventricle to connect with the inferior papillary muscle. The right ventricle tapers into the pulmonary trunk, into which it ejects blood when contracting. The pulmonary trunk branches into the left and right pulmonary arteries that carry the blood to each lung. The pulmonary valve lies between the right heart and the pulmonary trunk. The left heart has two chambers: the left atrium, and the left ventricle, separated by the mitral valve. The left atrium receives oxygenated blood back title: Systole text: Systole The systole is the part of the cardiac cycle during which some chambers of the heart muscle contract after refilling with blood. The term "systole" originates from New Latin via Ancient Greek συστολή (sustolē): from συστέλλειν (sustellein, "to contract") via [σύν (syn, "together") + στέλλειν (stellein, "send"). The use of systole, "to contract", is very similar to the use of the English term "to squeeze". The mammalian heart has four chambers: the left atrium above the left ventricle (lighter pink, see graphic), which two are connected through the mitral (or bicuspid) valve; and the right atrium above the right