Heart Facts | Heart physiology/anatomy

Heart physiology/anatomy

The human heart is a complex organ weighing around 250g, and is essential for pumping blood all around the body. Without it our body organs and tissues would die due to oxygen starvation. The heart resides close to the anterior chest wall and is surrounded by the pericardial cavity, which has a lining called the pericardium. The muscular heart has four chambers, called the right and left atria, and right and left ventricles.

These chambers exist to allow the blood to be pumped around the body. The right atrium receives deoxygenated blood (blood lacking in oxygen) from the two major veins known as the superior vena cava and the inferior vena cava, and then transfers this blood through the tricuspid valve to the right ventricle. This valve is necessary to prevent the blood flowing backwards into the right atrium. Blood in the right ventricle then passes through the pulmonary semilunar valve to the pulmonary trunk which supplies the pulmonary arteries with blood for gas exchange in the lungs. The left atrium then receives oxygenated blood (blood rich in oxygen) from the pulmonary veins, and the mitral valve (also called bicuspid valve) helps the blood flow to the left ventricle. The more muscular left ventricle (it is thicker than the right ventricle due to the fact that it has to pump blood a further distant) transfers blood to the ascending aorta. This blood rich in oxygen then passes through the descending aorta to the rest of the body.

In the next post I will consider another important part of heart physiology and anatomy, that of the heart valves.