Doctors discuss how common the condition is, why it happens — and whether Trump's symptoms align with his diagnosis.

The memo also detailed that POTUS underwent “bilateral lower extremity venous Doppler ultrasounds were performed and revealed chronic venous insufficiency, a benign and common condition, particularly in individuals over the age of 70.

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.