High cholesterol levels increase the risk of arteriosclerosis
In recent years, researchers have changed their mind about how LDL cholesterol influences the risk of cardiovascular disease. It used to be thought that excess cholesterol simply builds up on the walls of blood vessels. But that has turned out not to be true. Depending on their age and lifestyle, most people have small inflammations in the walls of their blood vessels. These can develop in different ways. In people who have high LDL cholesterol, the phagocytes (scavenger cells) in blood “eat” more cholesterol particles. This means that cholesterol is more likely to stick to the walls of affected blood vessels.
Inflammations can also weaken the blood vessel wall, which might then tear. If blood suddenly comes into contact with the cholesterol-rich deposits as a result, a blood clot might form. That is because our bodies try to seal the wound in the blood vessel wall, just like when scabs form if you cut your skin.
If this happens, the consequences will depend on various things, including how big the blood clot is. A big clot can completely block the blood vessel, causing a or stroke. But the blood clots that form are often only small – they fix the damage in the blood vessel wall and do not have any noticeable consequences. Then the cut heals on its own. This can lead to scarring and calcification of the blood vessel wall, which can gradually make the blood vessel narrower without blocking it completely. The blood vessel wall becomes thicker and stiffer. The medical term for the hardening of blood vessel walls is arteriosclerosis.
Inflammations can develop in any artery in the body. They are particularly dangerous in the large arteries that carry blood to the brain and heart. Narrow coronary blood vessels can cause chest pain (pectoral angina) during physical strain. If a coronary blood vessel becomes blocked, blood will no longer flow to part of the heart muscle, which might result in a heart attack. If a blood vessel in the brain becomes blocked, it might lead to a stroke.