The Structure of Heart

The Structure of Heart

  • The heart is a muscular organ that pumps blood around the body. It is located slightly to the left in the chest cavity and is approximately the size of a fist.
  • The heart is made up of four chambers: the left atrium, the right atrium, the left ventricle, and the right ventricle.
  • Blood flows into the heart through veins and is pumped out through arteries. The largest artery is the aorta, and the largest vein is the vena cava.
  • The two atria are smaller and have thinner walls than the two ventricles. This is due to the fact that ventricles have to pump blood out of the heart, needing more force.
  • A wall called the septum separates the left and right sides of the heart to prevent oxygen-rich and oxygen-poor blood from mixing.
  • Blood flow through the heart is one-way due to the presence of valves. These valves prevent the backflow of blood and maintain the direction of blood flow.
  • There are four valves in the human heart: the mitral valve and the aortic valve on the left side, and the tricuspid valve and the pulmonary valve on the right side.
  • The heart muscle is controlled by electrical signals that initiate each heartbeat. These signals start at the sinoatrial (SA) node, often referred to as the heart’s natural pacemaker.
  • Oxygen-depleted blood returns to the heart from the body via the vena cava into the right atrium. It then moves to the right ventricle, which pumps it to the lungs for oxygenation through the pulmonary artery.
  • Oxygenated blood returns to the heart from the lungs via the pulmonary veins into the left atrium. It then moves to the left ventricle, which pumps it to the rest of the body through the aorta.
  • The heart has its own blood supply, the coronary arteries, which bring oxygen and nutrient-rich blood to the heart muscle. A heart attack can occur if these arteries become blocked.
  • The cardiovascular system is part of the larger circulatory system, which includes the lungs (for oxygen intake and carbon dioxide removal) and the veins, arteries, and capillaries that transport blood throughout the body.