How does the heart work?

The main function of the heart is to pump blood and oxygen to the body. Your heart beats between 60-90 times a minute and over 100,000 times a day.

The heart has four chambers. The upper chambers are the right and left atria and the lower chambers are the right and left ventricles. In addition, there are two major blood vessels-the pulmonary artery and aorta, which carry blood away from the heart.

The right side of the heart receives blood from the body and pumps it through the pulmonary artery to the lungs where it is supplied with oxygen. This oxygen-rich blood is then returned to the left side of the heart where it is pumped through the aorta to the rest of the body.

Separating the chambers and major blood vessels are 4 different valves, which act like one-way doors allowing blood to flow in one direction only.

  • The tricuspid valve lies between the right atrium and right ventricle and directs flow between these two chambers.
  • The pulmonic valve sits between the right ventricle and pulmonary artery, allowing blood to flow to the lungs to receive oxygen.
  • The mitral valve is positioned between the left atrium and left ventricle, which is the main pumping chamber of the heart.
  • The aortic valve directs the oxygen-rich blood from the left ventricle into the aorta and to the rest of the body.

4-chambers-and-heart-valves

What is aortic stenosis?

Aortic stenosis is a narrowing of the aortic valve. Because the aortic valve does not fully open, the heart has to work harder to pump blood to the rest of the body.

People with severe aortic stenosis may complain they have chest pain, feel tired or short of breath. If left untreated, aortic stenosis may lead to heart failure.

 

aortic-stenosis-cross-section

What causes aortic stenosis?

Aortic stenosis may be caused by several different conditions.

  • Degenerative Changes-In some elderly people, the aging process may cause calcium build up on the valve leaflets. Calcium can make the leaflets stiff and narrow the aortic valve.
  • Rheumatic Fever-This infection can cause scar tissue to develop on the valve leaflets. Scar tissue may stiffen and narrow the valve so it does not fully open.
  • Congenital Heart Defect-The aortic valve typically consists of three leaflets. In some cases, the leaflets are not fully formed and do not function properly. This problem, however, may not cause any symptoms until people are 40-50 years old.