The tests – the Elecsys troponin T high-sensitive assay (Roche Diagnostics) and the ARCHITECT STAT high-sensitivity troponin I assay (Abbott Diagnostics) – measure the levels of cardiac troponin in the blood in people suspected of having a heart attack. Troponin is a protein that is released into the blood when heart muscle is damaged, often as the result of a heart attack.

Standard cardiac troponin tests are typically carried out 10-12 hours apart so that a change in troponin levels can be detected. For many people, this means that they have to be admitted to hospital for observation while the testing is carried out.

High-sensitivity troponin tests have been developed that are able to detect lower levels of troponin in the blood, and therefore can detect a change in levels of troponin earlier and enable an earlier discharge for patients who have not had a heart attack. “Use of these high-sensitivity tests enables the earlier detection of changes in troponin levels” says Professor Carole Longson, NICE Health Technology Evaluation Centre Director. “This in turn can allow doctors to rule out a diagnosis of a specific type of heart attack called a non-ST-segment elevation myocardial infarction (NSTEMI) within as little as 4 hours from the patient being seen in the emergency department. The increased sensitivity of these tests could mean a reduced length of stay for people without raised levels of troponin, and earlier treatment for those with a confirmed NSTEMI.”

As with standard cardiac troponin tests, the new tests need to be used alongside clinical history taking and ECG monitoring to diagnose NSTEMI. This is because cardiac troponin levels can also be raised in people who do not have coronary heart disease.

A further high-sensitivity cardiac troponin test - the AccuTnI+3 assay (Beckman Coulter) is recommended for research to gain information on its use for the early rule out of NSTEMI in people presenting to an emergency department with a suspected acute coronary syndrome.

Ends

Notes to Editors

About the NICE diagnostics guidance on the early rule out of myocardial infarction using high-sensitivity troponin tests

1. The NICE diagnostics guidance for high-sensitivity troponin tests is available on the NICE website.

About acute myocardial infarction (AMI)

1. AMI is part of a group of conditions collectively known as acute coronary syndrome (ACS), which includes both ST-segment-elevation myocardial infarction (STEMI) and non-ST-segment-elevation myocardial infarction (NSTEMI), and unstable angina.
2. These conditions are associated with common symptoms but have different underlying pathologies; STEMI is usually associated with a relatively large amount of damage to the myocardium (heart muscle) caused by a major blockage in the coronary artery, and can be detected with ST-elevation on an ECG trace. By comparison, NSTEMI is associated with relatively less damage to myocardium caused by partial blockage of the coronary artery or blockage of a smaller artery, and does not produce ST-elevation on ECG.
3. Acute coronary syndromes arise from an obstruction in the coronary arteries, usually caused by atherosclerosis and build-up of plaque which ruptures. When blood flow to the heart is reduced or blocked for a significant length of time (around 30-60 minutes) damage to cardiomyocytes (heart muscle cells) occurs, a pathological change which distinguishes an AMI from unstable angina.
4. Patients with ACS generally present with chest pain, a symptom which is responsible for around 700,000 emergency department attendances per year in England and Wales and 253,765 emergency admissions per year.
5. During 2011/12, the Myocardial Ischaemia National Audit Project (MINAP) reported 79,433 admissions with AMI recorded in England and Wales, 32,439 (41%) of which were categorised as STEMI, and 46,994 (59%) were categorised as NSTEMI.
6. The incidence of acute myocardial infarction increases with age, with the average age of first STEMI being 65 years, and of first NSTEMI 70 years. The incidence is also greater amongst men, with men being twice as likely to have an AMI as women.

About the NICE Diagnostics Assessment Programme

1. For further information about the NICE diagnostics assessment programme see Developing NICE diagnostic technologies guidance  
2. Topics to be considered by the Programme are routed through the related Medical Technologies Evaluation Programme. Further information about this can be found at Developing NICE medical technologies guidance

About NICE

The National Institute for Health and Care Excellence (NICE) is the independent body responsible for driving improvement and excellence in the health and social care system. We develop guidance, standards and information on high-quality health and social care. We also advise on ways to promote healthy living and prevent ill health.

Our aim is to help practitioners deliver the best possible care and give people the most effective treatments, which are based on the most up-to-date evidence and provide value for money, in order to reduce inequalities and variation.

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