Peripheral artery disease (P.A.D.) is a disease in which plaque builds up in the arteries that carry blood to your head, organs, and limbs. Plaque is made up of fat, cholesterol, calcium, fibrous tissue, and other substances in the blood.
Painless swelling may affect both legs and may include the calves or even the thighs. The effect of gravity makes the swelling most noticeable in the lower part of the body. Foot, leg, and ankle swelling is common when the person also: Is overweight.
Congestive heart failure causes the ankles and feet to swell because the heart is not pumping as much blood to the kidneys. This causes fluid retention, which results in the ankles and other areas of the body swelling up. Kidney failure can also cause swollen feet and ankles, again because of fluid retention. Though some swelling of the ankles in pregnancy is normal, if the ankles start to swell quickly, it may be a sign of eclampsia, explains WebMD.