Chest pain, pressure or tightness in the chest, or a squeezing or aching sensation in the middle of the chest

Pain or discomfort that radiates to the shoulders, arms, back, neck, jaw, or teeth, and in some cases may reach the upper part of the intestine

Nausea, indigestion, heartburn, or abdominal pain

shortness of breath

Dizziness, lightheadedness, or fainting

sweating

A heart attack usually causes chest pain that lasts more than 15 minutes. Some sufferers experience mild chest pain, while others experience more severe chest pain. The patient usually describes his feeling of discomfort by feeling pressure or heaviness in his chest, although some patients do not feel any pain or pressure in the chest at all. In women, heart attack symptoms are often not clear. It may appear as a feeling of nausea or pain in the back or jaw area.

Some people have heart attacks suddenly, but people usually have warning signs several hours or days before a heart attack.

What to do if you or someone else has a heart attack

Call 911, or the emergency number in your country or city. Don''t ignore the symptoms of a heart attack. If you can''t get an ambulance or emergency car for you, ask a neighbor or friend to take you to the nearest hospital. Don''t drive yourself unless you have no other options. As your condition may worsen, driving can put you and others in danger.

Chew and then swallow the aspirin while you wait for emergency help. Aspirin helps prevent your blood from clotting. And when taken during a heart attack, it can reduce the risk of heart failure. Don''t take aspirin if you''re allergic to it, or your doctor has told you not to take aspirin at all.

Take nitroglycerin, if it has been prescribed to you. If you think you''re having a heart attack and your doctor has previously prescribed nitroglycerin, take it as directed while you wait for emergency medical help.

Begin CPR if the person is unconscious. If the person is not breathing or their heart is not beating, then begin CPR to maintain blood flow after seeking emergency medical help.

Press firmly and quickly into the middle of the person''s chest with relatively rapid, regular strokes, about 100 to 120 compressions per minute.

If an automated external defibrillator is immediately available and the person is unconscious, follow the device''s instructions for use.