Overview Tests Treatment Sources

Tests
The goal of testing for angina is to distinguish between chest pain that is not heart-related (such as that due to skeletal muscle injury), that is due to treatable angina (not heart damage), and that is due to a heart attack. When a patient presents to the emergency room with an acute coronary syndrome – a group of symptoms that suggest heart injury – they are evaluated with a variety of laboratory and non-laboratory tests. These are used to determine the cause of the pain and the severity of the condition. Since some treatments for a heart attack must be given within a short period of time to minimize heart damage, an accurate diagnosis must be quickly confirmed.

Laboratory Tests
Cardiac biomarkers, proteins that are released when muscle cells are damaged, are frequently ordered to help differentiate angina from a heart attack. These include:

• Troponin - the most commonly ordered and cardiac-specific of the markers; will be elevated within a few hours of heart damage and remain elevated for up to two weeks
• CK-MB – one particular form of the enzyme creatine kinase that is found mostly in heart muscle and rises when there is damage to the heart muscle cells
• BNP or NT-proBNP – released by the body as a natural response to heart failure; increased levels of BNP, while not diagnostic for a heart attack, indicate an increased risk of cardiac problems in persons with acute coronary syndrome
• Myoglobin – a protein released into the blood when heart or other skeletal muscle is injured

One or more of these tests are usually ordered initially and then 1 or 2 more times in the next 12 to 16 hours to look at changes in concentrations. If these cardiac biomarkers are normal, then it is much less likely that the symptoms and chest pain are due to heart muscle damage and more likely that the pain is due to angina.

Other more general screening tests may also be ordered to help evaluate the patient’s major body organs, electrolyte balance, blood sugar, and red and white blood cells to see whether there are any excesses, deficiencies, or dysfunctions that may be causing or exacerbating the patient’s symptoms. These include:

• Comprehensive Metabolic Panel– a group of usually 14 tests that is used as a broad screening tool to asses the current status of a person’s kidneys, liver, electrolyte and acid/base balance, blood sugar, and blood proteins
• Complete Blood Count – a test used to determine a person’s general health status and to screen for a variety of disorders, such as anemia and infection

Non-Laboratory Evaluations
A range of non-laboratory evaluations and tests are used to assess chest pain and other symptoms. These include:

• A medical history, including an evaluation of risk factors such as age, CAD, diabetes, and smoking
• A physical examination
• An electrocardiography (ECG or EKG) – a test that looks at the heart’s electrical activity and rhythm
• Continuous ECG monitoring – the patient wears a monitor that evaluates heart rhythm over a period of time

Based on the findings of these tests, other procedures may be necessary, including:

• An exercise stress test
• Chest X-ray
• Radionuclide imaging – a radioactive compound is injected into the blood to evaluate blood flow and show images of narrowed blood vessels around the heart
• Echocardiography – ultrasound imaging of the heart
• Coronary catheterization – in this procedure, a thin flexible tube is inserted into an artery in the leg and threaded up to the coronary arteries to evaluate blood flow and pressure in the heart and the status of the arteries in the heart
• Coronary angiography – X-rays of arteries using a radiopaque dye to help diagnose CAD; this procedure is performed during coronary catheterization

On This Site

Tests: CK, Myoglobin, CK-MB, AST, Troponin, Cardiac biomarkers, BNP
Conditions: Heart attack, Heart disease

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