Acute coronary syndrome (ACS) is a term given to a group of symptoms. They are associated with chest pain at rest or during mild exertion. It also refers to certain type of heart attack known as unstable angina . This is a very serious condition. It indicates a heart attack could soon occur.

ACS can be a life-threatening condition. If you think you have ACS seek immediate medical treatment.


ACS is caused by a narrowing of the coronary arteries. These blood vessels carry blood to the heart muscle. The blood flow to the heart muscle is either greatly reduced or completely blocked. This leads to heart muscle damage or death.

Blood clots can sometimes cause the narrowing of the arteries. The narrowing most often happens from years of plaque build-up in an artery. This is called atherosclerosis .

Coronary Artery

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Risk Factors

The following factors increase your chances of developing acute coronary syndrome:

  • A family history of heart disease
  • You are a man over 45 years old or a woman over 55 years old
  • Being overweight or obese
  • Smoking
  • High cholesterol , especially high LDL ("bad") cholesterol and low HDL (“good”) cholesterol
  • High blood pressure
  • Diabetes
  • Being sedentary
  • Having angina, a previous heart attack, or other types of coronary artery disease


ACS is very serious. It requires immediate medical treatment. Contact your doctor if you experience any of these symptoms:

  • Angina—chest pain, pressure, tightness, burning, or other discomfort that may last a few minutes, go away, and then come back; often occurs after physical exertion, emotional stress or eating a large meal
  • Unstable angina—often occurs at rest, while sleeping, or with very little exertion; can last as long as 30 minutes.
  • Pain or discomfort in one or both arms, shoulders, the back, the neck, jaw, or stomach
  • Shortness of breath that accompanies chest pain or may occur just before it
  • Feeling light-headed or dizzy
  • Nausea and vomiting may occur
  • Sweating often occurs


Your doctor will ask about your symptoms and medical history. A physical exam will be done. If you suspect ACS, call an ambulance. At the hospital, tests may include the following:

  • Electrocardiogram (ECG or EKG)—measures the rate and regularity of your heartbeat; can show damage done to the heart muscle
  • Blood tests to measure different enzymes that are released when cells in the heart muscle dies including:
    • Troponin test—considered the most accurate test; can determine if a heart attack has occurred and how much new damage was done to the heart
    • CK or CK-MB test—measures creatine kinase (CK) in the blood
    • Myoglobin test—checks for the presence of myoglobin in the blood
  • Nuclear heart scan—radioactive tracers outline heart chambers and major blood vessels leading to and from the heart
  • Cardiac catheterization —can determine pressure and blood flow in the heart's chambers, collect blood samples from the heart, and examine the arteries of the heart by x-ray
  • Coronary angiography —produces images of blood flow through the heart; will show where there are blockages are
  • Echocardiogram —a test that uses sound waves to create a moving picture of your heart
  • Chest x-ray —images of the inside of the chest to assess heart size and show lung congestion and the presence of pneumonia


If you are having a heart attack, doctors will:

  • Work quickly to restore blood flow to the heart
  • Closely monitor vital signs to detect and treat complications
To restore blood flow, the main treatments are:

  • Aspirin is given to all patients suspected of acute coronary syndrome.
  • Anti-ischemic drugs, such as nitroglycerin , are used to help relieve chest pain.
  • Thrombolytic drugs are used to dissolve blood clots. When given soon after a heart attack begins, these drugs can limit or prevent permanent damage to the heart. To be most effective, they need to be given within one hour after the start of heart attack symptoms. Some thrombolytic drugs are:
  • Angioplasty —a catheter is inserted into a blocked artery. A balloon is inflated and deflated. This will allow blood to flow again. A stent may be placed.
  • Coronary artery bypass surgery —arteries or veins are taken from other areas in your body. They are used to bypass the blocked arteries in your heart.
  • Oxygen is given to all patients.

Based on a 2008 review, treating ACS with angiography and revascularization (restoring blood flow to the heart) may reduce the rate of being hospitalized again. But the surgery did not reduce the rate of death or heart attack.


To help reduce your chances of getting ACS, take the same heart-healthy lifestyle steps to prevent other forms of coronary artery disease such as:

  • Eating a well-balanced diet. It should be that is low in saturated fats. The diet should also be rich in fruits, vegetables, and whole grains.
  • Exercising regularly.
  • If you smoke, quit .
  • Manage you diabetes, blood pressure, and cholesterol. This can include lifestyle changes and medication.