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.

Approximately one million Americans suffer a heart attack each year. Four hundred thousand of them die as a result of their heart attack.

Medically Reviewed by a Doctor on 4/4/2013

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Heart Attack Warning Symptoms and Signs

Heart Attack Symptoms and Early Warning Signs

Heart attack is the number one killer of both men and women in the U.S. Each year, about 1.1 million Americans suffer a heart attack, and 460,000 of these are fatal. Most of the deaths from heart attacks are caused by ventricular fibrillation of the heart that occurs before the victim of the heart attack can reach an emergency room. Those who reach the emergency room have an excellent prognosis; survival from a heart attack with modern treatment should exceed 90%. The 1% to 10% of heart attack victims who die later include those victims who suffer major damage to the heart muscleinitially or who suffer additional damage at a later time. Fortunately, procedures such as coronary angiogramand PTCA (coronary balloon angioplasty), and clot dissolving drugs are available that can quickly open blocked arteries in order to restore circulation to the heart and limit heart muscle damage. In order to optimally benefit heart attack victims and limit the extent of heart damage, these treatments to open blocked arteries should be given early during a heart attack.

Knowing the early warning signs of heart attack is critical for prompt recognition and treatment. Many heart attacks start slowly, unlike the dramatic portrayal often seen in the movies. A person experiencing a heart attack may not even be sure of what is happening. Heart attack symptoms vary among individuals, and even a person who has had a previous heart attack may have different symptoms in a subsequent heart attack. Although chest painor pressure is the most common symptom of a heart attack, heart attack victims may experience a diversity of symptoms that include:

  • Pain, fullness, and/or squeezing sensation of the chest
  • Jaw pain, toothache, headache
Picture of the heart

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