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Troponin T Gen4
MessagePerformed in Chemistry
Test Code
TROPOT
CPT Codes
84484
Preferred Specimen
Green Top LiHep, Plasma
Other Acceptable Specimens
SST Gold, Red
Specimen Stability
Refrigerated 24 hours
Frozen 1 year
Frozen 1 year
Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Oxalate/fluoride plasma
Stabilized with azide
Collected in an outdated/expired tube
Hemolyzed, icteric or lipemic
Contaminated
Stabilized with azide
Collected in an outdated/expired tube
Hemolyzed, icteric or lipemic
Contaminated
FDA Status
FDA Approved
Setup Schedule
Daily, Sunday through Saturday
Report Available
Less than 4 hours
Clinical Significance
Troponin T (TnT) is a component of the contractile apparatus of the striated musculature. Although the function of TnT is the same in all striated muscles, TnT originating exclusively from the myocardium (cardiac TnT, molecular weight 39.7 kD) clearly differs from skeletal muscle TnT. As a result of tis high tissuespecificity, cardiac troponin T (cTnT) is a cardiospecific, highly sensitive marker for myocardial damage. In cases of acute myocardial infarction (AMI), troponin T levels in serum rise about 3-4 hours after the occurrence of cardiac symptoms and can remain elevated for up to 14 days.
Troponin T is an independent prognostic marker which can predict the near-, midand even long-term outcome of patients with acute coronary syndrome (ACS).
In addition, four multicenter trials involving more than 7000 patients have shown that troponin T is also useful to identify patients that benefit from anti-thrombotic therapy (GPIIb/IIIa inhibitors, low molecular weight heparin).
Because it has been proven that cardiac troponin is an independent marker which best predicts the outcome of patients with ACS and is a useful tool in guiding anti-thrombotic therapy, the joint committee of the European Society of Cardiology (ESC) and American College of Cardiology (ACC) redefined myocardial infarction (MI). According to this new definition, MI is diagnosed when blood levels of cardiac troponin are above the 99th percentile of reference limit (of a healthy population) in the clinical setting of acute ischemia. The imprecision (coefficient of variation) at the 99th percentile for each troponin assay should be defined as less than or equal to 10%.
Thus, patients with ACS and elevated cardiac troponin and/or CK-MB are considered to have experienced a non-ST-elevation MI (NSTEMI); whereas the diagnosis of unstable angina is established if cardiac troponin and CK-MB are within the reference range. This redefinition of MI is now also part of the new ACC/AHA guidelines for the management of patients with unstable angina and NSTEMI.
Based on the redefinition of myocardial infarction several recommendations have been published concerning the role of cardiac troponin testing in patients with ACS.
Myocardial cell injury leading to elevated troponin T concentrations in the blood can also occur in other clinical settings like congestive heart failure, cardiomyopathy, myocarditis, heart contusion, renal failure, lung embolism, stroke, left ventricular dysfunction in septic shock, and interventional therapy like cardiac surgery, non-cardiac surgery, PTCA, and drug-induced cardiotoxicity. In many of these cases – in particular in patients with renal failure – increased levels of cardiac troponin T identify patients with poorer prognosis.
In summary, elevated troponin levels are indicative of myocardial injury, but elevations are not synonymous with an ischemic mechanism of injury. The term MI should be sued when there is evidence of cardiac damage, as detected by marker proteins, in a clinical setting consistent with myocardial ischemia. If the clinical circumstance suggests that an ischemic mechanism is unlikely, other causes of cardiac injury should be pursued.
The Elecsys Troponin T assay employs two monoclonal antibodies specifically directed against human cardiac troponin T. The antibodies recognize two epitopes (amino acid position 125-131 and 136-147) located in the central part of the cardiac troponin T protein, which consists of 288 amino acids. Elecsys Troponin T detects free troponin T as well as binary and ternary complexes of troponin.
Troponin T CalSet contain recombinant human cardiac troponin T (rec. hcTNT). The rec. hcTNT is isolated from cell culture E. coli BL21 containing a pET vector with human cardiac troponin T isoform 3 gene. After fermentation, the cells are disrupted by sonication and rec. hcTNT is purified by ion exchange chromatography. Purified rec. hcTNT is further characterized by SDS PAGE, Western blotting, immunological activity, and protein content.
Troponin T is an independent prognostic marker which can predict the near-, midand even long-term outcome of patients with acute coronary syndrome (ACS).
In addition, four multicenter trials involving more than 7000 patients have shown that troponin T is also useful to identify patients that benefit from anti-thrombotic therapy (GPIIb/IIIa inhibitors, low molecular weight heparin).
Because it has been proven that cardiac troponin is an independent marker which best predicts the outcome of patients with ACS and is a useful tool in guiding anti-thrombotic therapy, the joint committee of the European Society of Cardiology (ESC) and American College of Cardiology (ACC) redefined myocardial infarction (MI). According to this new definition, MI is diagnosed when blood levels of cardiac troponin are above the 99th percentile of reference limit (of a healthy population) in the clinical setting of acute ischemia. The imprecision (coefficient of variation) at the 99th percentile for each troponin assay should be defined as less than or equal to 10%.
Thus, patients with ACS and elevated cardiac troponin and/or CK-MB are considered to have experienced a non-ST-elevation MI (NSTEMI); whereas the diagnosis of unstable angina is established if cardiac troponin and CK-MB are within the reference range. This redefinition of MI is now also part of the new ACC/AHA guidelines for the management of patients with unstable angina and NSTEMI.
Based on the redefinition of myocardial infarction several recommendations have been published concerning the role of cardiac troponin testing in patients with ACS.
Myocardial cell injury leading to elevated troponin T concentrations in the blood can also occur in other clinical settings like congestive heart failure, cardiomyopathy, myocarditis, heart contusion, renal failure, lung embolism, stroke, left ventricular dysfunction in septic shock, and interventional therapy like cardiac surgery, non-cardiac surgery, PTCA, and drug-induced cardiotoxicity. In many of these cases – in particular in patients with renal failure – increased levels of cardiac troponin T identify patients with poorer prognosis.
In summary, elevated troponin levels are indicative of myocardial injury, but elevations are not synonymous with an ischemic mechanism of injury. The term MI should be sued when there is evidence of cardiac damage, as detected by marker proteins, in a clinical setting consistent with myocardial ischemia. If the clinical circumstance suggests that an ischemic mechanism is unlikely, other causes of cardiac injury should be pursued.
The Elecsys Troponin T assay employs two monoclonal antibodies specifically directed against human cardiac troponin T. The antibodies recognize two epitopes (amino acid position 125-131 and 136-147) located in the central part of the cardiac troponin T protein, which consists of 288 amino acids. Elecsys Troponin T detects free troponin T as well as binary and ternary complexes of troponin.
Troponin T CalSet contain recombinant human cardiac troponin T (rec. hcTNT). The rec. hcTNT is isolated from cell culture E. coli BL21 containing a pET vector with human cardiac troponin T isoform 3 gene. After fermentation, the cells are disrupted by sonication and rec. hcTNT is purified by ion exchange chromatography. Purified rec. hcTNT is further characterized by SDS PAGE, Western blotting, immunological activity, and protein content.
