A heart attack occurs when a coronary artery is permanently blocked or the blockage lasts for longer than about 30 minutes. The area of the heart muscle that is prevented from receiving blood from the blocked artery is starved for oxygen and dies. An infarct is the area of tissue that is damaged due to lack of oxygen and nutrients.
A heart attack generally causes severe chest pain that lasts for longer than 15 minutes. The pain is often characterized as crushing or pressing, is localized beneath the breast bone and often radiates to the left shoulder and arm or into the neck and jaws. The person often sweats profusely, is nauseous, short of breath and feels weak. It is also possible to have a silent heart attack where no symptoms occur. The results of a silent heart attack may show up on an electrocardiogram at a later date.
It is extremely important to seek medical attention immediately if you think you are having a heart attack. If a loved one has the symptoms but doesnt want to make a possibly unnecessary trip to the emergency room, strongly encourage them to go anyway. Thousands die each year because they did not seek help immediately or because they thought their symptoms might only be indigestion. Sixty percent of the people that die from heart attack do so within the first hour after the onset of symptoms and before seeking medical assistance. Prompt treatment greatly improves the chances of survival.