Definition

A heart attack occurs when blood flow to the heart muscle is interrupted. Oxygen cannot get to the heart muscle, causing tissue damage or tissue death.

Causes

A heart attack may be caused by:

• Thickening of the walls of the arteries feeding the heart muscle (coronary arteries)
• Build up of fatty plaques in the coronary arteries
• Narrowing of the coronary arteries
• Spasm of the coronary arteries
• Development of a blood clot in the coronary arteries
• Embolism that affects the coronary arteries

Risk Factors

The risk of heart attack is greater in males and older adults.

Factors that may increase your chance of developing a heart attack include:

• Obesity
• Smoking
• High blood pressure
• Sedentary lifestyle
• High blood cholesterol —specifically, high LDL cholesterol, and low HDL cholesterol
• High blood triglycerides
• Diabetes
• Stress
• Family members with heart disease
• Using testosterone therapy medication

Symptoms

Symptoms include:

• Squeezing, heavy chest pain behind breastbone, especially with:
  • Exercise or exertion
  • Emotional stress
  • Cold weather
  • A large meal
  • Usually comes on quickly
• Pain in the left shoulder, left arm, or jaw
• Shortness of breath
• Sweating, clammy skin
• Nausea
• Weakness
• Loss of consciousness
• Anxiety, especially feeling a sense of doom or panic without apparent reason

Unusual symptoms of heart attack—may occur more frequently in women:

• Stomach pain
• Back and shoulder pain
• Confusion
• Fainting

If you think you are having a heart attack, call for emergency medical services right away.

Diagnosis

Your bodily fluids may be tested. This can be done with:

• Blood tests—To look for certain enzymes found in the blood within hours or days after a heart attack
• Urine tests—To look for certain substances found in the urine within hours or days after a heart attack

Your heart function may be tested. This can be done with:

• Electrocardiogram (EKG) —to look for evidence of blockage or damage
• Echocardiogram —to examine the size, shape, function, and motion of the heart
• Stress test —Records the heart’s electrical activity under increased physical stress, usually done days or weeks after the heart attack

Images may be taken. This can be done with:

• Nuclear scanning—show areas of the heart muscle where there is diminished blood flow
• Electron-beam computed tomography (EBCT)—to make detailed pictures of the heart, coronary arteries, and surrounding structures
• Coronary angiography —To look for narrowing or blockage in the coronary arteries

Treatment

Treatment includes:

• Aspirin
• Oxygen
• Pain-relieving medication
• Nitrate medications
• Other antiplatelet agents
• Beta-blockers and/or angiotensin-converting enzyme (ACE) inhibitor medications
• Anti-anxiety medication
• Cholesterol-lowering medications such as statin drugs

Within the first six hours after a heart attack, you may be given medications to break up blood clots in the coronary arteries.

Prevention

Preventing or treating coronary artery disease may help prevent a heart attack.

• Maintain a healthy weight.
• Begin a safe exercise program. Follow your doctor’s advice.
• If you smoke, talk to your doctor about ways to quit.
• Eat a healthy diet. Your diet should be low in saturated fat and rich in whole grains, fruits, and vegetables.
• Properly treat long-term conditions, like high blood pressure, diabetes, and high cholesterol.
• Manage stress.
• Ask your doctor about taking a small, daily dose of aspirin.
  • Although most people are able to tolerate such a low dose of aspirin, even this small amount can rarely lead to serious bleeding, particularly from the gastrointestinal (GI) tract.
  • Aspirin may not work as well when combined with other pain medications.

Heart and Stroke Foundation http://www.heartandstroke.com/site/c.ikIQLcMWJtE/b.2796497/k.BF8B/Home.htm

Heart and Stroke Foundation http://www.heartandstroke.com

ST-elevation myocardial infarction (STEMI). EBSCO DynaMed website. Available at:
http://www.ebscohost.com/dynamed
Updated August 27, 2014. Accessed September 29, 2014.

What is a heart attack? National Heart Lung and Blood Institute website. Available at:
http://www.nhlbi.nih.gov/health/health-topics/topics/heartattack/
Updated December 13, 2013. Accessed September 29, 2014.

7/6/2009 DynaMed’s Systematic Literature Surveillance
http://www.ebscohost.com/dynamed:
Antithrombotic Trialists’ (ATT) Collaboration, Baigent C, Blackwell L, et al. Aspirin in the primary and secondary prevention of vascular disease: collaborative meta-analysis of individual participant data from randomised trials. Lancet. 2009;373:1849-1860.

2/3/2014 DynaMed’s Systematic Literature Surveillance
http://www.ebscohost.com/dynamed:
Finkle W, Greenland S, et al. Increased risk of non-fatal myocardial infarction following testosterone therapy prescription in men. PLoS One. 2014;9(1).