Why do cardiac marker tests when you are above 50?

A normal lipid profile test measures the number of fat molecules called lipids. Lipids are fatty compounds that perform a variety of functions in your body. They're part of your cell membranes and help control what goes in and out of your cells. They help move and store energy, absorb vitamins, and make hormones. Too many lipids in your blood can lead to a fatty substance building up in your arteries. This can cause your arteries to narrow and increase your risk of cardiovascular disease. 

A lipid panel measures five different types of lipids from a blood sample:

1. Low-density lipoprotein (LDL) cholesterol: LDL cholesterol has a reputation for being the "bad cholesterol." When its level is high, excess LDL cholesterol contributes to plaque buildup in the arteries. 
    
2. Very-low-density lipoprotein (VLDL) cholesterol: This type of cholesterol comes from food you've recently eaten. It's typically in low amounts when you have a fasting blood panel. An increase in this type of cholesterol in a fasting sample may indicate that your body isn't processing cholesterol correctly.
    
3. High-density lipoprotein (HDL) cholesterol: This cholesterol earned the title of "good cholesterol" because it helps you eliminate extra cholesterol. It brings it to your liver and ends up in your excreta. A healthy amount of HDL cholesterol works against plaque buildup in arteries. This improves your risk of heart disease and stroke.
    
4. Total Cholesterol (TC): This is your overall cholesterol level — the combination of LDL-C, VLDL-C and HDL-C.
    
5. Triglycerides: A type of fat from food. Excess triglycerides in the blood are associated with cardiovascular disease and pancreatic inflammation.

Above 50, one should be careful if the lipid panel shows certain signs of being out of range. Ignoring these may be harmful in the long run. The key question is, whether the risk of heart ailment is increasing. This is where market tests come in handy!

Marker tests are thus advanced tests one needs to do in case specific base readings are not in line with the reference ranges. These tests measure the level of hormones, enzymes or proteins in the bloodstream to indicate particular damage. Abnormal levels usually indicate higher risk levels or, in the case of medications, the effectiveness of the same.

Some of the key advanced cardiac marker tests are:

1. C-Reactive Protein: Normal CRP or hs (high sensitivity) CRP test measures the level of CRP, a protein made by the liver. Hs-CRP can catch even a tiny increase in CRP, released in case of inflammation in the body. A high level of hs-CRP in the blood is linked to an increased risk of heart attacks. According to Mayo Clinic, "a hs-CRP test may be most useful for people who have a 10% to 20% chance of having a heart attack within the next 10 years. This is known as intermediate risk."
    
2. Apolipoprotein: Apolipoproteins are the major protein component of lipoproteins (whose function is to transport lipids – HDL, VLDL and LDL) and are important in maintaining lipoproteins' structural integrity and solubility. 2 types of test indicate a higher risk of a heart ailment
   1. Apolipoprotein A-1 (Apo A-1): Apolipoprotein A1 is the major protein for the high-density lipid (HDL), also known as "good" cholesterol. Apo A1 helps the HDL to take up cholesterol from the tissues and is bound by receptors in the liver where the cholesterol is destroyed. Assessing the levels of Apolipoprotein A1 directly reflects the high-density lipoprotein levels. This way, apolipoprotein A can help lower your cardiovascular disease risk. it is usually recommended for individuals with risk factors such as high blood pressure, high cholesterol, obesity, diabetes, smoking, or a family history of heart disease. 
   2. Apolipoprotein B (Apo B) is used alongside other routine lipid tests to help determine an individual's risk of developing CVD - not as a general population screen but rather where patients have a family history of heart disease. Apo B is the primary protein component of lipoproteins such as very low-density lipoprotein (VLDL), low-density lipoprotein (LDL), and chylomicrons. It binds to LDL or "bad" cholesterol, causing plaque accumulation in the blood vessels. This can lead to the development and progression of cardiovascular disease that can be life-threatening if left untreated.
       
3. Lipoprotein A: Lipoprotein A is a mixture of Low-density lipoprotein (LDL) and a protein called apolipoprotein (A). Lp-A levels are primarily determined by genetics. Unlike other types of cholesterol, lp-A levels are not significantly affected by diet, exercise, or lifestyle changes. That is why testing for Lp-A is essential, particularly for individuals with a strong family history of cardiovascular (heart or blood vessel) disease, as it is considered an independent risk factor for heart attack and stroke. While both Lp-A and LDL are types of cholesterol and contribute to the buildup of plaques in arteries, Lp-a comprises LDL along with an additional protein called apolipoprotein (a), which potentially makes it more damaging to your arteries and, therefore, can be an individual contributor to cardiovascular problems.
    
4. Natriuretic Peptide Tests (BNP, NT-proBNP): Natriuretic peptides are proteins that your heart and blood vessels make. Natriuretic peptide tests measure the amount of these proteins in a blood sample. Two natriuretic peptides can be measured to check for possible heart failure. 
   1. Brain natriuretic peptide (BNP) is a protein that the heart makes and releases BNP into your bloodstream when it's working harder than normal to pump blood. The BNP tells your blood vessels to open wider and your kidneys to get rid of water and salt through urine. This helps reduce the workload on your heart by lowering blood pressure and reducing the amount of blood your heart has to pump
   2. N-terminal pro-b-type natriuretic peptide (NT-proBNP): Like BNP, your heart makes larger amounts of NT-proBNP when it has to work harder to pump blood.
       
5. Homocysteine: Homocysteine is an amino acid. Amino acids are chemicals in your blood that help create proteins. Vitamin B12, vitamin B6 and vitamin B9 (folate) break down homocysteine to generate other chemicals your body needs. If you have more than 50 mcmol/L, the excess homocysteine may damage the lining of your arteries (blood vessels that carry oxygen-rich blood throughout your body). High homocysteine levels can also lead to blood clots or blood vessel blockages. Artery damage or blood clots significantly raise your risk of heart attack. 
    
6. Creatinine kinase (CK): This enzyme can be measured several times over 24 hours. It will often at least double if you've had a heart attack. However, because levels of CK can go up in many other conditions besides a heart attack, it is not very specific.
    
7. CK-MB: This is a subtype of CK. It is more sensitive for finding heart damage from a heart attack. CK-MB rises 4 to 6 hours after a heart attack. But it is generally back to normal in a day or two. Because of this, it's not helpful when a healthcare provider is trying to figure out if your recent chest pain was a heart attack.
    
8. Myoglobin: This is a small protein that stores oxygen. It is measured occasionally. Myoglobin is sometimes measured in addition to Troponin to help diagnose a heart attack. It is also not very specific for finding a heart attack. Skeletal and cardiac muscles both contain the protein myoglobin. After a tissue injury, it is quickly released.
    
9. Troponin: Protein test is used to measure levels of the same in the heart muscle. If one's blood has these proteins, it indicates that the heart muscle is damaged. There are two types of Troponin – a) Troponin I, which is unique to heart muscle, and b) Troponin II, which does exist in other muscles in a minimal amount – excess of it does indicate heart damage. The levels increase sharply within 3-12 hours after a heart attack and peak 24 hours after the event – remaining high for several days.
    

FAQs

1. What is the purpose of a cardiac enzyme test?

The cardiac enzyme test detects signs of damage to the heart muscle following a heart attack or other cardiac conditions. It can also evaluate heart function after procedures like coronary artery bypass grafting (CABG) or angioplasty.

2. What role does Troponin T play in diagnosing heart-related conditions?

Troponin T, a protein in heart muscle, is a key marker in blood tests for diagnosing heart attacks. The high-sensitivity troponin T test helps healthcare professionals assess heart attack risk and the likelihood of heart disease.

3. Why are cardiac biomarkers measured?

Measuring cardiac biomarkers helps evaluate heart damage and diagnose conditions causing symptoms such as chest pain and shortness of breath.

4. Who should consider taking a cardiac risk marker test?

Individuals with a family history of heart disease or those at a higher risk of developing cardiac issues at a younger age may benefit from a cardiac risk marker test.

5. What does it mean if heart enzyme levels are high?

Elevated levels of heart enzymes often indicate the presence of cardiovascular disease or other heart-related issues. Troponin biomarker tests are primarily used to identify heart damage resulting from a heart attack or acute coronary syndrome (ACS).