Troponin Test

The troponin test measures the level of troponin in your blood. Troponin is a type of protein found in the muscles of your heart. Troponin isn’t normally found in the blood. When heart muscles become damaged, troponin is sent into the bloodstream. As heart damage increases, greater amounts of troponin are released in the blood.

High levels of troponin in the blood may mean you are having or recently had a heart attack. A heart attack happens when blood flow to the heart gets blocked. This blockage can be deadly. But quick diagnosis and treatment can save your life.

Other names: cardiac troponin I (cTnI), cardiac troponin T (cTnT), cardiac troponin (cTN), cardiac-specific troponin I and troponin T

Troponin Test Details

To understand what is Troponin test, you must first know what Troponin in blood means; and what is Troponin I and Troponin T.

Troponin is a group of three proteins:

• Troponin C

• Troponin T

• Troponin I

Now, exactly what are Troponin I and T as cardiac makers? Only Troponin I and Troponin T regulate heart muscle and tissue contraction, not Troponin C.

Now, back to the Troponin test. A Troponin test can measure the levels of Troponin in blood. These proteins are released after damage to the heart muscles. The greater the damage to the heart, the higher the Troponin levels in the blood.

Troponin levels may rise approximately 4 or 6 hours after heart damage. Troponin in blood continues to remain raised for up to 2 weeks thus providing a greater time range to detect the problem. In angina patients, raised Troponin levels mean aggravation in the condition and a high risk of heart failure.

However, the Troponin test should not be the only investigation to diagnose a heart problem. It should be combined with physical examination, medical information, ECG, etc.

Purpose of Test 

Troponin is a type of protein found in heart muscle but not typically found in the blood. However, when the heart is damaged, this protein is released into the bloodstream. Even a slight increase in troponin level can signal some damage to the heart. Very high levels of troponin indicate that a heart attack has occurred.2

You might have a troponin test if you have signs of a heart attack or severe heart failure. Sometimes, there are warnings (e.g., fatigue, chest tightness) in the months before a heart attack, but one can occur without any warning. A heart attack generally begins suddenly and worsens rapidly.

Indications for a troponin test include:

• Pain, pressure, tightness, or discomfort in the chest
• Arm, shoulder, neck, back, upper abdomen, or jaw pain
• Shortness of breath
• Weakness or fatigue
• Nausea, vomiting
• Pale or blue skin or lips
• Sweating
• Heart palpitations (a sense that your heart is beating rapidly)
• Rapid breathing
• Confusion, dizziness, or loss of consciousness

A silent heart attack is a heart attack without the typical symptoms. It can be characterized by a cold sweat, dizziness, and generalized weakness. If your healthcare provider is concerned that you could be having a silent heart attack, you might have a troponin test.

What is it used for?

This test is most often used to diagnose a heart attack. It is sometimes used to monitor angina, a condition that limits blood flow to the heart and causes chest pain. Angina sometimes leads to a heart attack.

Why do I need a troponin test?

You may need this test if you have been admitted to the emergency room with symptoms of a heart attack. These symptoms include:

• Chest pain or discomfort
• Pain in other parts of the body, including your arm, back, jaw, or neck
• Trouble breathing
• Nausea and vomiting
• Fatigue
• Dizziness
• Sweating

If you have symptoms of a heart attack, call 911 immediately.

What happens during a troponin test?

A healthcare professional will take a blood sample from a vein in your arm, using a small needle. After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.

Risks and Contraindications

A heart attack is a medical emergency, but a troponin test does not cause any adverse effects. The results should be interpreted in the context of your medical history, symptoms, and other tests.

Before the Test 

You will likely have this test at the same time as other tests that are used to assess the likelihood of a heart attack. You don’t need to do anything to prepare for it.

Timing 

A troponin level is obtained using a standard blood sample, drawn from a vein. The procedure takes a few minutes.

Food and Drink 

You don’t need to make any special dietary adjustments for this test, as food and drink do not affect the result.

During the Test

A nurse or a phlebotomist will perform your blood troponin test. If you are also being evaluated for an emergency heart condition, your healthcare provider will likely be nearby or in the room checking your heart sounds, pulse, and other diagnostic heart tests.

Pre-Test

Along with your test, you are likely to have other tests that can help your healthcare providers know if you are having a heart attack. You will probably have an EKG. This is a non-invasive test in which electrodes are placed on your chest to detect the electrical activity (and any abnormal changes) produced by your heart as it beats.

You will also have your blood oxygen level measured with a non-invasive pulse oximeter. This is a small device which is placed on your finger.

You might also have your blood oxygen, carbon dioxide, and pH measured with an arterial blood gas (ABG).1 An ABG test requires an arterial blood sample and does not use the blood sample for your troponin test, which is collected from a vein.

Throughout the Test 

In the ER or your healthcare provider’s office, a band is tied around your upper arm a few inches above the vein which is poked to draw a blood sample for the troponin test. How this test is performedThe skin is cleaned and a needle will be inserted to draw the blood It will take a few minutes to lose the band and also the needle.

Sometimes, if you are in the emergency room or staying as an inpatient in the hospital, an intravenous (IV, in a vein) line will be placed in one of your veins so that blood can be collected as necessary. This prevents the need for repeated punctures.

The blood sample for your troponin test might be collected using your IV if you already have one in place.

Post-Test

If you have a needle puncture for your troponin test, you will have a bandage placed over the puncture site and your nurse will check on you periodically to make sure that it has stopped bleeding.

Procedure

The Troponin I test procedure is a quick, simple test using a few milliliters of blood from the patient’s vein. The test timing must be a minimum of 6 to 12 hours after the start of cardiac symptoms. No prior test preparation is required. The procedure takes around 10 minutes only using a rapid test kit.

The Troponin I card test is the most reliable Troponin I test. According to a study: “The Troponin I Test Device (Whole Blood/Serum/Plasma) has been compared with a leading commercial cTnI EIA test, demonstrating an overall accuracy of 98.5%.” (Ref: www.ekoweb.fi/images/pdf/Cardiac_Troponin_I.pdf)

The Troponin I test procedure is a qualitative test to detect raised Troponin I levels in whole blood/serum/plasma. The blood sample can be drawn either by fingerstick or venipuncture method. The blood sample is added to a handy test device using various other aids like droppers, capillary tubes, etc. This device is like a quick reader with markers as indicators.

Test Report

A normal range of the Troponin I test is below 0.04 ng/mL. Troponin concentration over Troponin normal range that is at 0.40 ng/mL and higher, could be an indicator of a heart injury: Please consult a doctor. Troponin concentrations of 0.04-0.39 ng/mL may require a series of Troponin tests. Over 0.40 ng/mL is well outside the Troponin normal range and needs immediate doctor consultation.

What do the results mean?

If your results show normal troponin levels for 12 hours after chest pain has started, it’s unlikely that your symptoms were caused by a heart attack.

• Congestive heart failure
• Kidney disease
• Blood clots in your lungs

If you have questions about your results, talk to your healthcare provider.

Learn more about laboratory tests, reference ranges, and understanding results.