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

OBJECTIVE: To investigate the prognostic utility of Heart Foundation (Australia) risk stratification table in an ED chest pain population.

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 30 days. 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 7 days (13.5%, 95% CI 11.1-16.4%) and 93 MACE at 30 days (14.4%%, 95% CI 11.9-17.3%). Diagnostic performance (c-statistic) of the National Heart Foundation risk classification for ACS, MI, 7 and 30 day MACE was 0.74 for each (95% CI 0.71-0.77). Although sensitivity of the high-risk classification for MI, 7 and 30 day MACE was high (99-100%), specificity was low (48-50%).

CONCLUSION: The Heart Foundation risk classification shows only fair predictive performance for MI, 7 and 30 day MACE. With specificity of approximately 50%, the recommendation for coronary care admission for all high-risk patients is hard to justify.