please press F5 on your keyboard to enter presentation mode Welcome to the Eastern Health Pathology guide to hsTnT. The information in this presentation has been collated by Dr Ann Read, Chemical Pathologist, and A/Prof Gish New, Director of Cardiology at Eastern Health, and prepared by Tony O’Neill from Pathology. Click here when you are ready to continue

High Sensitivity Troponin (hsTnT) What is it? Troponin (Tn) is a protein released from necrotic cardiac muscle cells. Two forms, TnI and TnT, can be found in the circulation when even minor necrosis occurs. Eastern Health Pathology has used a Roche TnT method since 1999 hsTnT is the latest generation of assay and will be used across EH from 7 th February 2011 onwards (replacing the existing TnT method) Assay Facts The new assay units are ng/L (previous methods were ng/mL) hsTnT results cannot be directly compared with the previous method Reference Range (as defined by 99 th percentile) is ng/L Almost all patients will have measurable TnT using this method, although most will be very low in the absence of ACS. Interpreting Results If Delta hsTnT is >50% and either result is >14 → supportive of ACS If hsTnT is elevated but stable (ie Delta hsTnT is <50%) → consider other causes of myocardial injury (see below). Non-STEMI (but not Unstable Angina) can be ruled out if both results are normal 6 hours after presentation and there are no other symptoms of ACS. A single normal result can be used if symptoms began more than 6 hours ago An elevated hsTnT is abnormal and suggestive of myocardial ischaemia, although not necessarily due to ACS. Note that UA is part of the spectrum of ACS, but does not require a rise in Troponin/CK or ECG changes When interpreting hsTnT results, the timeframe since symptom onset must be considered. Most ACS patients show a rapid rise in troponin levels 3-18 hours after the onset of chest pain, followed by a gradual decrease over a period of days Further information regarding clinical interpretation is provided overleaf Using Delta hsTnT Clinical Application Non-ACS causes of an elevated Troponin Agzew Y. Elevated serum cardiac troponin in non-acute coronary syndrome Clin Cardiol 2009; 32: A Result Interpretation Matrix has been provided on the next page to assist with interpretation of hsTnT results Patients who present with a clinical history suggestive of ACS and hsTnT of >100 ng/L can be provisionally diagnosed Diagnosis of non-ST Elevation Myocardial Infarction (non-STEMI) may require demonstration of a changing hsTnT level over paired samples collected at least 3 hours apart in the window 3-12 hours post symptom onset (Delta hsTnT). The Delta hsTnT can be calculated using the tool found in the online Pathology Handbook (the EH Intranet page) or at Click here when you are ready to proceed

hsTnT Result Interpretation Guide Click here when you are ready to proceed

ACS Classification Click here when you are ready to proceed

Clinical Progression of ACS Acute Coronary Syndrome Guidelines Working Group Med J Aust 2006 : 184 (8 Suppl); S9-29 Defining ACS Over Time Click here when you have finished

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