An external validation of the HEART pathway among Emergency Department patients with chest pain

The impact of an outpatient disposition strategy for patients with HEART score 0-3 (HEART pathway) on HEART score prognostic accuracy is unclear. Our objective is to perform an external validation the HEART score in the setting of recent implementation of the HEART pathway. We conducted an external validation study of the HEART pathway among patients presenting to our ED with chest pain 6 weeks after institutional implementation of a HEART pathway outpatient disposition pathway. We reviewed the charts of 625 consecutive patients with chest pain. Data abstracted included all elements of the HEART score to include history, electrocardiogram (ECG) read, patient age, patient risk factors, and troponin levels. We also reviewed each patient's record for evidence of major adverse cardiac events (MACE) to include mortality, myocardial infarction, or coronary revascularization over 6 weeks following their initial ED visit. We double-abstracted 10% of the charts for quality assurance purposes. Of 625 charts, 449 patients met all criteria for study inclusion. Of these, 25 subjects (5.56%) experience 6-week MACE. No subject with a score of 3 or less has a MACE at 6 weeks (100% sensitivity, 38.7% specificity). The area under the receiver operator curve (AUROC) is 0.898 (95% confidence interval 0.847-0.950). Kappa coefficients for inter-rater reliability range from 0.62 for the history component of the HEART score to 1.0 for troponin. A low HEART score (0-3) maintains excellent sensitivity for predicting 6-week MACE in the setting of an outpatient disposition pathway for these patients.