Ck or creatine kinase is found within most muscle cells and is released into the bloodstream when muscular cellular necrosis or damage occurs. In the ed study ck mb myoglobin and ctni were equally sensitive 100 for the detection of ami in patients who presented 7 4 14 h after onset of chest pain.
Myoglobin was the earliest marker and its negative predictive value npv was significantly higher than for ck mb mass and troponin t from 3 to 6 hours after the onset of symptoms myoglobin versus ck mb mass p 03.
Myoglobin ck mb troponin. Indeed cardiac troponin is central to the definition of acute myocardial infarction mi in the consensus guidelines from the european society of cardiology esc and the american college of. Ck mb is cardiac specific and is useful for the early diagnosis of acute myocardial infarction. However ctni was the most specific serum marker specificity 91 9 compared to ck mb 85 6 myoglobin 61 4.
Myoglobin b type natriuretic peptide bnp creatine kinase isoenzyme mb ck mb and cardiac troponin t ctn t are cardiac biomarkers frequently used for evaluating cardiac risk factors. However ck is not specific. Serial plasma concentrations of myoglobin creatine kinase mb ck mb isoenzyme and cardiac troponin i ctni were measured in 25 patients with a confirmed diagnosis of acute myocardial infarction ami and 74 patients who were suspected of ami but were subsequently ruled out for this diagnosis.
An abnormal troponin t predicted a subsequent event while abnormal ck mb or myoglobin did not. Myoglobin versus troponin t p 01. 1 0 to 7 9 for myoglobin 1 0 0 3 to 3 2 and for ck mb 0 9 0 2 to 3 4.
This includes the heart so with the same principle as troponin elevations in ck could indicate heart muscle damage. Currently the ck marker largely has been replaced by cardiac troponins and ck mb isoenzyme. Ck mb typically is detectable in the serum 4 6 hours after the onset of ischemia peaks in 12 24 hours and normalizes in 2 3 days.
The npv of myoglobin reached 89 4 hours after the onset of symptoms. Myoglobin is a heme protein normally found in skeletal and cardiac muscle with a molecular weight of 17 8 kda.