Hardening of the arteries happens when the arteries are damaged and start to accumulate plaque, according to WebMD. The plaque causes the arteries to harden and to narrow. At first, symptoms are silent, but as the arteries narrow, chest pain can result.
Hardening of the arteries is also called atherosclerosis and is a leading cause of cardiovascular disease, claims WebMD. This includes heart attack, peripheral vascular disease and stroke.
LDL, which is the "bad" type of cholesterol, invades the injured part of the artery wall, claims WebMD. White blood cells detect the cholesterol and attack it. However, instead of removing the cholesterol, the white blood cells get tangled up with the cholesterol and plaque forms.
Some types of plaque stop growing after they reach a certain size and don't leave the wall of the artery. This type of plaque doesn't cause symptoms. Other types can eventually cause a total blockage of the artery. In an artery that leads to the heart, this can cause a heart attack. If the artery is in the brain, it can cause a stroke, claims WebMD.
Other symptoms of hardening of the arteries include leg pain when walking, sexual dysfunction, weakness or numbness in the limbs, renal failure, or high blood pressure, according to the Mayo Clinic.