Troponin is a protein located in the cells of the heart muscles. Also referred to as “cardiac troponin” proteins, these are usually classified as type I, type T, and type C. People who have suffered a heart attack generally have elevated cardiac troponin levels in their bloodstream, as a consequence of heart muscle damage. There are tests that can help determine troponin I and T levels, to see if the heart’s muscle has indeed suffered damage.
High-Sensitivity Troponin I Test
Troponin I tests have been along for quite some time, but a more recent and more sensitive version of the test surfaced, and it could help predict cardiovascular disease with better accuracy. It’s implied that this test can predict heart attacks and strokes even years before they occur.
The high-sensitivity troponin I test was part of a study conducted by Atherosclerosis Risk in Communities (ARIC), looking to examine the outcomes of atherosclerosis. The study participants were 15,000 middle-aged men and women from different corners of the US.
During the study, over 8.000 people between the ages of 54 and 74 were studied, all of them with no history of cardiovascular disease. After performing this blood test, 90 percent of them turned out to have troponin in their bloodstream.
Interestingly enough, the high-sensitivity troponin I test might be more effective in people over the age of 60, compared to an analysis of risk factors such as blood pressure and cholesterol levels. These risk factors in older people might not give that much information to help predict cardiovascular disease as this high-sensitivity test can.
Troponin and heart damage
It turns out that people who experience a heart attack have elevated troponin levels in their blood. These are enzymes that are released once the heart muscle has suffered damage. Blood tests are generally performed on people suspected to have had a heart attack to check for troponin levels.
The two common enzymes sought out when performing a blood test for diagnosing a heart attack are I and T. People who have never suffered a heart attack have almost zero troponin in their bloodstream.
Even if troponin level tests have been around for a while, they can only detect elevated levels of this enzyme. The high-sensitivity troponin I test, however, can detect very low troponin levels, making it more accurate than the alternative.
Performing a high-sensitivity troponin test
Doctors that choose to perform troponin tests are interested in ruling out any other conditions that might cause the symptoms of a heart attack. Whether the test performed is for troponin T or I, the information provided by either test is just as relevant in diagnosing a heart attack.
These tests are generally performed when someone is admitted to the emergency room as a heart attack suspect. They could show signs of chest pain, dizziness, nausea and vomiting, arrhythmia, fatigue, excessive sweating, shortness of breath, and other symptoms associated with a heart attack.
Even a slight elevation of troponin levels can indicate heart damage. Generally speaking, people who have suffered a heart attack with have high troponin levels for about 10 or 14 days after the episode. The elevation occurs after three to six hours after suffering a heart attack.
However, troponin examination is never the standalone test used to determine a heart attack. It’s usually paired with an EKG or an echocardiogram. Doctors may even choose to perform more blood tests to see if troponin levels rise or fall over the duration of several hours.
People who have angina and high troponin levels could learn their condition is getting worse and are at a higher risk of having a heart attack. High troponin levels can indicate other things as well, such as congestive heart failure, cardiomyopathy, or myocarditis (heart inflammation).
If your troponin test results are good over several measurements, your heart’s muscle hasn’t suffered any damage, which means that your heart attack signs could be caused by another medical condition.
Troponin and other muscles
Troponin is a cardiac marker, which means that it’s used to indicate heart muscle damage and heart muscle damage only. However, there have been a few cases where people who have a skeletal muscle disease and high troponin levels.
As a general rule, it’s very rare for people who have experienced a heart attack to have normal troponin levels. There are also rare cases where people with high troponin having had no heart attacks whatsoever. For example, conditions such as pulmonary embolism and renal failure can also lead to elevated troponin levels.
Conclusion
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