Authors' objectives:

This review sought to answer the following questions:

- What is the value of individual clinical features in the diagnosis of an acute myocardial infarction (MI)? - How accurate are electrocardiogram (ECG) changes in the diagnosis of acute coronary syndrome (ACS)? - What is the most cost-effective way to manage patients presenting in the community with suspected acute MI? - What is the value of a resting ECG in the diagnosis of CHD? - What is the value of an exercise ECG in the diagnosis of CHD? - How effective are rapid access chest pain clinics in the diagnosis of exertional angina? - What is the impact of rapid access chest pain clinics (RACPCs) compared with other possible models of care in the investigation of exertional angina?

Authors' results and conclusions: Acute chest pain - clinical symptoms and signs: No clinical features in isolation were useful in ruling in or excluding an ACS. The clinical features most helpful were pleuritic pain (LR+ 0.19, 95% CI 0.14 to 0.25) and pain on palpation (LR+ 0.23, 95% CI 0.08 to 0.30). Acute chest pain: resting ECG: The presence of ST elevation was highly specific for MI, with LR+ 13.1 (95% CI 8.28 to 20.6). A completely normal ECG was reasonably useful at ruling out a myocardial infarction (LR+ 0.14 (95% CI 0.11 to 0.20). Black box studies of clinical interpretation of ECGs found very high LR+ (145 in the best quality study), but low sensitivity (LR 0.58). Simulation exercise of management strategies for suspected ACS: Point of care testing with troponins was cost-effective. Pre-hospital thrombolysis on the basis of ambulance telemetry was more effective but more costly than thrombolysis performed in hospital. Chronic chest pain: resting ECG: Resting ECG features were not found to be very useful. Presence of Q-waves had LR+ 2.56 (95% CI 0.89 to 7.30). One study reported a high LR+ of 9.96 (95% CI 2.5838.5) for QRS notching. Chronic chest pain: exercise ECG: Presence of ST depression had LR+ 2.79 (95% CI 2.53 to 3.07) for a 1 mm cutoff and 3.85 (95% CI 2.49 to 5.98) for a 2 mm cutoff. The LRs were 0.44 (95% CI 0.40 to 0.47) (1 mm) and 0.72 (95% CI 0.65 to 0.81) (2 mm). Other methods of interpreting the exercise ECG did not result in dramatic improvements in these results. The test performed better in men than women. RACPCs: No true evaluative studies were identified. Weak evidence was found to suggest that these clinics might be associated with reduced admission to hospital of patients with non-cardiac pain, better recognition of ACS, earlier specialist assessment of exertional angina and earlier diagnosis of non-cardiac chest pain. Simulation exercise of models of care for investigation of suspected exertional angina: RACPCs were predicted to result in earlier diagnosis of both confirmed CHD and non-cardiac chest pain than models of care based around open access exercise tests or routine cardiology outpatients, but were more expensive. The benefits of RACPCs disappeared if waiting times for further investigation (e.g. angiography) were long (6 months).

Authors' recommendations: - In patients in whom an ACS is suspected, emergency referral for further assessment in a specialist setting is justified. - ECG interpretation in acute chest pain can be highly specific for diagnosing MI. - Point of care testing with troponins is cost-effective in triaging patients with suspected ACS. - Resting ECG and exercise ECG are of only limited value in the diagnosis of CHD. - The potential advantages of RACPCs are lost if there are long waiting times for further investigation.

Authors' methods: Systematic review, Economic modelling

Project Status: Completed

URL for project: http://www.hta.ac.uk/1115

Year Published: 2004

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: England, United Kingdom

Organisation Name: NIHR Health Technology Assessment programme

Contact Address: NIHR Journals Library, National Institute for Health and Care Research, Evaluation, Trials and Studies Coordinating Centre, Alpha House, University of Southampton Science Park, Southampton SO16 7NS, UK

Contact Name: journals.library@nihr.ac.uk

Contact Email: journals.library@nihr.ac.uk

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