Normal Heart Anatomy

The heart has four separate chambers. The two upper chambers are called the right and left atria. The atria are receiving chambers for blood returning from the body and the lungs. The wall dividing the two atria is called the atrial septum. The lower two chambers are the right and left ventricles. The ventricles are muscular chambers responsible for pumping blood to the body and lungs. The wall dividing the two ventricles is called the ventricular septum. There are four separate valves in the heart: the tricuspid valve, pulmonary valve, mitral valve, and aortic valve. The valves open to allow bloodflow forward and close prevent any backflow. Finally, there are a number of veins and arteries attaching to the heart. The superior and inferior vena cava drain blood back from the heart to the right atrium (see Normal blood flow). The pulmonary veins drain blood back from the lungs to the left atrium. The pulmonary artery connects to the right ventricle and directs blood out to the lungs. The aorta connects to the left ventricle and directs blood out to the body.