Acute coronary syndrome risk stratum code N

Guide for use:

CODE 1 ST-segment-elevation (myocardial infarction)

This code is used where persistent ST elevation of >=1mm in two contiguous limb leads, or ST elevation of >=2mm in two contiguous chest leads, or with new left bundle -branch block (BBB) pattern on the ECG.

This classification is intended for identification of patients potentially eligible for reperfusion therapy, either pharmacologic or intervention-based. Other considerations such as the time to presentation and the clinical appropriateness of instituting reperfusion are not reflected in this metadata item.

CODE 2 Non-ST-segment-elevation ACS with high-risk features

This code is used when presentation with clinical features consistent with an acute coronary syndrome with high-risk features which include any of the following:

• repetitive or prolonged (> 10 minutes) ongoing chest pain or discomfort;
• elevated level of at least one cardiac biomarker (troponin or creatine kinase-MB isoenzyme);
• persistent or dynamic ECG changes of ST segment depression >= 0.5mm or new T wave >= 2mm;
• transient ST-segment elevation (>= 0.5 mm) in more than 2 contiguous leads;
• haemodynamic compromise: Blood pressure < 90 mmHg systolic, cool peripheries, diaphoresis, Killip Class > 1, and/or new onset mitral regurgitation;
• sustained ventricular tachycardia;
• syncope;
• left ventricular systolic dysfunction (left ventricular ejection fraction < 0.40);
• prior percutaneous coronary intervention within 6 months or prior coronary artery bypass surgery;
• presence of known diabetes (with typical symptoms of ACS);or
• chronic kidney disease (estimated glomerular filtration rate < 60mL/minute) (with typical symptoms of ACS).

This classification is intended for identification of patients potentially eligible for aggressive medical management and coronary angiography and revascularisation.

CODE 3 Non-ST-segment-elevation ACS with intermediate-risk features

This code is used when presentation with clinical features consistent with an acute coronary syndrome and any of the following intermediate-risk features AND NOT meeting the criteria for high-risk ACS:

• chest pain or discomfort within the past 48 hours that occurred at rest, or was repetitive or prolonged (but currently resolved);
• age greater than 65yrs;
• known coronary heart disease: prior myocardial infarction with left ventricular ejection fraction >= 0.40 known coronary lesion more than 50% stenosed;
• no high-risk changes on electrocardiography (see high-risk features);
• two or more of the following risk factors: known hypertension, family history, active smoking or hyperlipidaemia;
• presence of known diabetes (with atypical symptoms of ACS);
• chronic kidney disease (estimated glomerular filtration rate < 60mL/minute) (with atypical symptoms of ACS); or
• prior aspirin use.

This classification is intended for identification of patients potentially eligible for accelerated diagnostic evaluation and further risk stratification.

CODE 4 Non-ST-segment-elevation ACS with low-risk features

This code is used when presentation with clinical features consistent with an acute coronary syndrome without intermediate or high-risk features of non-ST-segment-elevation ACS. This includes onset of anginal symptoms within the last month, or worsening in severity or frequency of angina, or lowering of anginal threshold.

This classification is intended for identification of patients potentially eligible for outpatient investigation discharge on upgraded medical therapy and outpatient investigation.