Prognostic Utility of the HEART Score in the Observation Unit

The evaluation of individuals with possible acute myocardial infarction (AMI) is time consuming and costly. Risk stratification early during an acute care encounter presents an opportunity for increased delivery of high-value care. We sought to evaluate if the HEART score could be used in the triage of low-risk versus high-risk patients directly home without cardiac testing. Retrospective review of 838 patients placed in an observation unit for evaluation of AMI was done at a single-center, tertiary care teaching hospital. Primary outcome was major adverse cardiac event-death, AMI, or revascularization-at 30 days from the index encounter. Participants' average age was 60.1 years, 40% were male, and 67% were African American. Complete data were available for all 838 patients, including 30-day follow-up at study completion. The primary endpoint was met in 14 patients (1.7%), all of whom were in the high-risk group, with HEART score ≥4. Of the low-risk patients, 8 (2.8%) had a positive functional study, 5 underwent subsequent coronary angiography, with none (0%) found to have obstructive coronary disease. In conclusion, our results suggest that patients with a HEART score ≤3 being evaluated for chest pain are at extremely low risk for major adverse cardiac events and may be safely discharged without provocative testing. Positive cardiac testing in this population is more likely to represent a false-positive finding, resulting in unnecessary testing. These findings should be prospectively validated.