Heart Attack
(Myocardial Infarction)

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Heart attack facts

  • A heart attack results when a blood clot completely obstructs a coronary artery supplying blood to the heart muscle and heart muscle dies.
  • The blood clot that causes the heart attack usually forms at the site of rupture of an atherosclerotic, cholesterol plaque on the inner wall of a coronary artery.
  • The most common symptom of heart attack is chest pain.
  • The most common complications of a heart attack are heart failure and ventricular fibrillation.
  • The risk factors for atherosclerosis and heart attack include elevated cholesterol levels, increased blood pressure, tobacco use, diabetes, male gender, and a family history of heart attacks at an early age.
  • Heart attacks are diagnosed with electrocardiograms and measurement of cardiac enzymes in blood.
  • Treatment guidelines emphasize treatment at a hospital capable of doing PCI (percutaneous coronary intervention) also termed as stenting or stent placement.
  • Early reopening of blocked coronary arteries reduces the amount of damage to the heart and improves the prognosis for a heart attack.
  • Medical treatment for heart attacks may include antiplatelet, anticoagulant, and clot dissolving drugs as well as angiotensin converting enzyme (ACE) inhibitors, beta blockers, and oxygen.
  • Interventional treatment for heart attacks may include coronary angiography with percutaneous transluminal coronary angioplasty (PTCA), coronary artery stents, and coronary artery bypass grafting (CABG).
  • Patients suffering a heart attack are hospitalized for several days to detect heart rhythm disturbances, shortness of breath, and chest pain.
  • Further heart attacks can be prevented by aspirin, beta blockers, ACE inhibitors, discontinuing smoking, weight reduction, exercise, good control of blood pressure and diabetes, following a low cholesterol and low saturated fat diet that is high in omega-3-fatty acids, taking multivitamins with an increased amount of folic acid, decreasing LDL cholesterol, and increasing HDL cholesterol.

What is a heart attack?

A heart attack (also known as a myocardial infarction or MI) is the damage and death of heart muscle from the sudden blockage of a coronary artery by a blood clot. Coronary arteries are blood vessels that supply the heart muscle with blood and oxygen. Blockage of a coronary artery deprives the heart muscle of blood and oxygen, causing injury to the heart muscle. Injury to the heart muscle causes chest pain and chest pressure sensation. If blood flow is not restored to the heart muscle within 20 to 40 minutes, irreversible death of the heart muscle will begin to occur. Muscle continues to die for six to eight hours at which time the heart attack usually is "complete." The dead heart muscle is eventually replaced by scar tissue.

Medically Reviewed by a Doctor on 7/16/2014

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Heart Attack Warning Symptoms and Signs

12 Heart Attack Symptoms and Early Warning Signs

Although chest pain or pressure is the most common symptom of a heart attack, heart attack victims may experience a diversity of symptoms that include:

  • Chest discomfort, manifest as pain, fullness, and/or squeezing sensation of the chest;
  • jaw pain, toothache, headache;
  • shortness of breath;
  • nausea,
  • vomiting,
  • general epigastric (upper middle abdomen) discomfort;
  • sweating;
  • heartburn and/or indigestion;
  • arm pain (more commonly the left arm, but may be either arm);
  • upper back pain;
  • general malaise (vague feeling of illness); and
  • no symptoms (approximately one quarter of all heart attacks are silent, without chest pain or new symptoms and silent heart attacks are especially common among patients with diabetes mellitus).
Picture of the heart