For example, deep vein thrombosis may develop in people who have had a heart attack Acute Coronary Syndromes (Heart Attack Myocardial Infarction Unstable Angina) Acute coronary syndromes result from a sudden blockage in a coronary artery. During prolonged bed rest and other occasions when the legs are not moving normally (such as after a leg injury or a stroke), blood flow slows because the person is lying down and the calf muscles are not contracting and squeezing the blood toward the heart.
