The document discusses first aid for heart attacks. It defines a heart attack as occurring when the coronary arteries become blocked, causing the heart muscle to die from lack of oxygen and nutrients. Signs of a heart attack include chest pain, shortness of breath, paleness, sweating, anxiety, irregular pulse, nausea and vomiting. The first aid treatment is to immediately call an ambulance, have the casualty chew an aspirin to help break up clots unless allergic, place them in a resting position, monitor their condition, and be prepared for further deterioration.