Anatomy of the Heart
The human heart comprises 4 “chambers”: two upper chambers known as the “atria” and two lower chambers known as the “ventricles”. The right side of the heart comprises the right atrium (RA) and right ventricle (RV). The left side comprises the left atrium (LA) and left ventricle (LV). The two sides are separated by a wall of muscles called the “septum”.
The heart pumps oxygenated blood to other parts of the body via the circulatory system. The circulatory system comprises a system of blood vessels that carry blood to and from the heart. The major blood vessels connected to the heart include the aorta, the Superior Vena Cava (SVC), the Inferior Vena Cava (IVC), the pulmonary artery and the pulmonary vein. Deoxygenated (oxygen-deficient) blood enters the RA via the SVC (from the upper part of the body) and IVC (from the lower part of the body). As the atria contracts, blood exits the RA and enters the RV via the tricuspid valve (the valve between the RA and RV). Once the RV contracts, blood leaves the heart via the pulmonary valve to the pulmonary artery and finally into the lungs, wherein it gets oxygenated. The pulmonary vein supplies oxygen-rich blood to the LA. Upon contraction of the LA, the blood flows from the LA to the LV via the mitral valve (the valve between the LA and LV). Oxygenated (oxygen-rich) blood is pumped from the LV via an aortic valve to the aorta (the main artery). These valves ensure that blood flows in the right direction and prevent backflow. The oxygenated blood then travels from the aorta via smaller arteries and into the body organs through the capillaries. In the capillaries, the blood delivers oxygen and nutrients into the organs, tissues, and cells and collects carbon dioxide and waste products. The now deoxygenated blood is collected into the veins and travels back to the RA where this cycle starts again.