How useful are the Heart Foundation risk criteria for assessment of emergency department patients with chest pain

Kelly AM – The Heart Foundation risk classification shows only fair predictive performance for MI, 7 and 30 day major adverse cardiac events (MACE). With specificity of approximately 50%, the recommendation for coronary care admission for all high–risk patients is hard to justify.

Methods

• A planned sub-study of a prospective observational study of adult patients with potentially cardiac chest pain who underwent evaluation for acute coronary syndrome (ACS) was conducted.
• Data collected included demographical, clinical, ECG, biomarker and outcome data.
• Outcome of interest was diagnostic utility of the classification system for ACS or myocardial infarction (MI) at index presentation and major adverse cardiac events (MACE) within 7 and 30days.
• MACE included death, cardiac arrest, revascularization, cardiogenic shock, arrhythmia and prevalent (cause of presentation) and incident (occurring within the follow-up period) MI.
• Analysis was by descriptive and receiver-operator curve analyses.

Results

• Seven hundred and sixty-eight patients were studied; 109 had MI (14.2%, 95% confidence interval [CI] 11.9-16.8%).
• There were 88 MACE at 7days (13.5%, 95% CI 11.1-16.4%) and 93 MACE at 30days (14.4%%, 95% CI 11.9-17.3%).
• Diagnostic performance (c-statistic) of the National Heart Foundation risk classification for ACS, MI, 7 and 30day MACE was 0.74 for each (95% CI 0.71-0.77).
• Although sensitivity of the high-risk classification for MI, 7 and 30day MACE was high (99-100%), specificity was low (48-50%).

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