The Food and Drug Administration (FDA) has approved the antiplatelet agent Plavix (clopidogrel bisulfate) as a treatment for preventing new blockages in arteries that have already been damaged by a severe heart attack. This severe type of heart attack is caused by the sudden, total blockage of an artery. Plavix first came on the market in November 1997 to reduce platelet activity in people with decreased blood flow to the heart due to coronary artery disease. Platelets are sticky blood cells that contribute to blood clot formation and blood vessel blockages. Two studies were recently done involving a total of about 50,000 individuals who received Plavix early in the course of a severe heart attack caused by total vessel blockage. The drug was shown to help improve blood flow and reduce the rates of recurrent heart attack, stroke, and death, sometimes in combination with aspirin or other anti-clotting therapies. (FDA)