When we're born, our blood vessels are flexible and elastic, and the blood is able to flow through them with ease. As we age, fatty deposits start to develop in the walls of our arteries and gradually they build up, forming lumps called plaques which extend into the middle of the artery, reducing the ease of blood flow through the artery. This process can be broken down into 3 stages:
- Fatty streaks – damage to the inner wall of the artery allows infiltration of fatty substances. At this stage artery damage is minimal and the blood flow isn't seriously affected.
- Soft plaque – repeated injury at the site of the fatty plaques results in a thickening of the artery's middle layer. Deposits of cholesterol, fatty substances, connective tissue and blood products form a soft cap or plaque. This bulges into the channel of the artery, restricting the flow of blood.
- Hard plaque – all 3 layers of the wall of the artery are affected. The artery's channel is now almost blocked.
This process can affect any organ. Atherosclerosis of the arteries:
- going to the brain can lead to a stroke
- can cause peripheral arterial disease or clogging of small arteries going to the legs
- in the heart can lead to angina or a heart attack.