The document provides warning signs and symptoms of heart attacks. It notes that up to 60% of heart attacks are "silent" with no noticeable symptoms. Common symptoms include chest pain and discomfort in the left arm, but heart attacks can occur without chest pains. Less common warning signs include abdominal pain, fatigue, nausea and cold sweats. The document recommends calling emergency services immediately if a heart attack is suspected and provides tips on first aid measures and equipment that can help prevent death from a heart attack.