Chronic venous insufficiency, or CVI, happens when veins in the legs can’t properly carry blood back to the heart. That can lead to blood pooling in the lower legs.

President Donald Trump was examined for swelling in his legs and has been diagnosed with chronic venous insufficiency, the White House announced Thursday.

Leavitt said Trump noted "mild swelling in his lower legs," which prompted the White House medical team to evaluate him. They concluded that Trump has chronic venous insufficiency -- a condition in which there isn't adequate blood flow in the veins in the legs. This can cause the blood to pool, causing swelling in the lower legs.