Cardiac marker

Table columns:
Test
Sensitivity and specificity
Approximate peak
Description

Table rows:
cells: Troponin test
The most sensitive and specific test for myocardial damage. Because it has increased specificity compared with CK-MB, troponin is a superior marker for myocardial injury.
12 hours
Troponin is released during MI from the cytosolic pool of the myocytes. Its subsequent release is prolonged with degradation of actin and myosin filaments. Isoforms of the protein, T and I, are specific to myocardium. Differential diagnosis of troponin elevation includes acute infarction, severe pulmonary embolism causing acute right heart overload, heart failure, myocarditis. Troponins can also calculate infarct size but the peak must be measured in the 3rd day. After myocyte injury, troponin is released in 2–4 hours and persists for up to 7 days.
cells: Creatine Kinase (CK-MB) test
It is relatively specific when skeletal muscle damage is not present.
10–24 hours
The CK-MB isoform of creatine kinase is expressed in heart muscle. It resides in the cytosol and facilitates movement of high energy phosphates into and out of mitochondria. Since it has a short duration, it cannot be used for late diagnosis of acute MI but can be used to suggest infarct extension if levels rise again. This is usually back to normal within 2–3 days.
cells: Lactate dehydrogenase (LDH)
LDH is not as specific as troponin.
72 hours
Lactate dehydrogenase catalyses the conversion of pyruvate to lactate. LDH-1 isozyme is normally found in the heart muscle and LDH-2 is found predominantly in blood serum. A high LDH-1 level to LDH-2 suggest MI. LDH levels are also high in tissue breakdown or hemolysis. It can mean cancer, meningitis, encephalitis, or HIV. This is usually back to normal 10–14 days.
cells: Aspartate transaminase (AST)
This was the first used.[6] It is not specific for heart damage, and it is also one of the liver function tests.
cells: Myoglobin (Mb)
low specificity for myocardial infarction
2 hours
Myoglobin is used less than the other markers. Myoglobin is the primary oxygen-carrying pigment of muscle tissue. It is high when muscle tissue is damaged but it lacks specificity. It has the advantage of responding very rapidly,[7] rising and falling earlier than CK-MB or troponin. It also has been used in assessing reperfusion after thrombolysis.[8]
cells: Ischemia-modified albumin (IMA)
low specificity
IMA can be detected via the albumin cobalt binding (ACB) test, a limited available FDA approved assay. Myocardial ischemia alters the N-terminus of albumin reducing the ability of cobalt to bind to albumin. IMA measures ischemia in the blood vessels and thus returns results in minutes rather than traditional markers of necrosis that take hours. ACB test has low specificity therefore generating high number of false positives and must be used in conjunction with typical acute approaches such as ECG and physical exam. Additional studies are required.
cells: Pro-brain natriuretic peptide
This is increased in patients with heart failure. It has been approved as a marker for acute congestive heart failure. Pt with < 80 have a much higher rate of symptom-free survival within a year. Generally, pt with CHF will have > 100.
cells: Glycogen phosphorylase isoenzyme BB
0.854 and 0.767[9]
7 hours
Glycogen phosphorylase isoenzyme BB (abbreviation: GPBB) is one of the three isoforms of glycogen phosphorylase. This isoform of the enzyme exists in cardiac (heart) and brain tissue. Because of the blood–brain barrier, GP-BB can be seen as being specific to heart muscle. GP-BB is one of the "new cardiac markers" which are considered to improve early diagnosis in acute coronary syndrome. During the process of ischemia, GP-BB is converted into a soluble form and is released into the blood. A rapid rise in blood levels can be seen in myocardial infarction and unstable angina. GP-BB is elevated 1–3 hours after process of ischemia.

Questions about this table:
originalText: what are the different cardiac biomarkers in heart disease
answer: answerTexts: Troponin
Creatine Kinase (CK-MB)
Lactate dehydrogenase (LDH)
Aspartate transaminase (AST)
Myoglobin (Mb)
Ischemia-modified albumin (IMA)
Pro-brain natriuretic peptide
Glycogen phosphorylase isoenzyme BB