Cardiac Enzymes (Cardiac Biomarkers)

What are cardiac enzymes (cardiac biomarkers)?

When your heart experiences damage or stress due to lack of oxygen, it releases substances called cardiac enzymes into the bloodstream. Enzymes are proteins that help your body manage metabolism and other chemical processes. 

What is a cardiac enzyme marker test?

An enzyme marker test is a blood test to measure specific biological markers (biomarkers) in your blood. High levels of cardiac enzymes can be a sign of a heart attack or stress on the heart.

How do healthcare providers use cardiac biomarkers?

Increases in cardiac enzymes can indicate acute coronary syndrome (ACS), myocardial ischemia or the presence of injury to the heart muscle.

Treatments for these conditions vary. An accurate diagnosis is critical to ensuring that you receive the appropriate care.

What’s the purpose of cardiac biomarkers?

Healthcare providers measure cardiac marker levels to:

• Screen for heart damage and other problems.
• Diagnose heart conditions that cause symptoms like chest pain and shortness of breath.
• Monitor how well heart medications and heart surgery work.
• Predict a prognosis (outlook) for various heart conditions.

Where do you get a cardiac enzyme marker test?

A cardiac enzyme marker test requires a blood draw. The blood draw takes just a few minutes. In an emergency situation, the blood draw takes place in an emergency department or hospital. For nonurgent situations, the test may take place at your healthcare provider’s office or a blood-testing lab.

What are the types of cardiac enzymes (cardiac biomarkers)?

There are different types of cardiac biomarkers. All of them are enzymes or proteins. Elevated heart enzymes may show that you have cardiovascular disease or other heart problems.

A biomarker test for troponin is the primary test healthcare providers use to detect heart damage from a heart attack or ACS. Troponin levels can rise for up to 12 hours after a heart attack. They stay elevated for up to two weeks. You may get several cardiac enzyme tests spaced several hours or days apart to measure these biomarkers.

Healthcare providers may also test for natriuretic peptides (NPs) that may be elevated in conditions like heart failure. Providers can measure various types of peptides, but they most commonly use N-terminal proBNP (NT-proBNP) in the assessment of strain on the heart due to heart failure.

Who needs a cardiac enzyme (cardiac biomarker) test?

Your healthcare provider may order a cardiac enzyme test if you have symptoms of a possible heart problem. These symptoms include:

• Chest pain.
• Dizziness.
• Nausea.
• Profuse sweating.
• Shortness of breath.
• Heart failure exacerbation.

What other blood tests do healthcare providers use to diagnose a heart attack or heart damage?

You may also get one or more of these blood tests:

• Complete blood count (CBC) to measure blood cell and platelet levels.
• Basic metabolic panel (BMP) or comprehensive metabolic panel to measure levels of electrolytes and proteins.
• Blood gas test (ABG) to measure oxygen, carbon dioxide and acid levels.

What other tools do healthcare providers use to diagnose a heart attack or heart damage?

In addition to lab (blood) tests, you may receive:

• Chest X-ray.
• Echocardiogram, such as a transesophageal echocardiogram (TEE).
• Electrocardiogram (ECG or EKG).
• Exercise stress test or nuclear cardiac stress test.
• Angiogram.
• Positron emission tomography (PET) scan.

A note from Cleveland Clinic

Was it a heart attack or not? Wondering about it can be a source of high anxiety. To move forward, you need answers. Healthcare providers use cardiac biomarkers to screen, diagnose and treat heart conditions. Elevated levels of cardiac enzymes (cardiac biomarkers) in your blood can be a sign of heart damage, stress or inflammation. Now is the time to ask questions about your cardiac enzymes and what your test results mean.