Chest pain representing acute coronary syndrome (ACS) is the most common reason patients presenting to the emergency department (ED) are admitted to the hospital. The treatment for ACS is early targeted therapy and missed cases results in increased morbidity and mortality. As a result many clinicians choose to admit patients for further evaluation, resulting in further testing and higher medical costs. The HEART score was developed in order to risk stratify these patients. The score is an acronym for history, EKG, age, risk factors, and troponin. Unlike other clinical decision rules, the components are scored 0, 1, or 2, allowing for a middle ground, and this CDR was uniquely developed for use in the ED. This research group has previously performed prospective validation studies assessing the HEART score. In this paper, the group compared the HEART, TIMI, and GRACE clinical decision rules and their ability to risk stratify low risk chest pain patients.
How does the HEART score compare to TIMI and GRACE scores in determining low risk chest pain patients?
All patients presenting to ten emergency departments in the Netherlands between October 2008 and November 2009 who complained of chest pain.
TIMI and GRACE score
Primary: Major Adverse Cardiac Event (MACE): Acute myocardial injury, PCI, CABG, coronary angiography showing correctable disease that was managed conservatively, death due to any cause.
Secondary: 6 week occurrence of MI or death, diagnosis of ACS within 3 months of presentation, coronary angiography within 3 months of presentation
Prospective, observational study (history was taken prospectively, but EKGs read by cardiologist retrospectively)
Patients who complained of dyspnea and palpitations, Additionally, those patients with EKGs notable for STEMI prehospital (these patients were transported to specific hospitals)
- 2440 patients included in enrollment
- 52 patients had invalid data on admission or lost to follow up
- 2388 followed for sufficient length to be included in study
- 407 patients (17%) had a MACE in entire study group
- 155 patients (6.4%) with AMI
- 251 patients (10.5%) underwent PCI
- 67 patients (2.8%) had a CABG
- 44 patients (1.8%) had coronary angio with conservatively managed correctable stenosis
|Clinical Decision Rule||
Low risk score
- Study asked a simple, clinically relevant question with patient centered outcome
- All data on HEART score is based on ED patients
- Large, multicenter study
- Excellent follow up (~98% of patients enrolled)
- Variability in history taking and EKG interpretation could lead to significant variation in provider scoring
- Primary endpoint (MACE) is a composite with individual pieces that are not equally patient relevant (i.e. death is not the same as AMI)
- Although the study is designed to capture all patients who presented with chest pain, there is always potential for missed cases
- Overall MACE rate (17%) higher than in other health care systems (i.e. US)
- C-statistics (AUC) measure accuracy which gives equal weight to sensitivity and specificity. In the emergency department, we are more concerned about discharging false negatives than admitting false positives. In other words, sensitivity is much more important to our clinical decision making than specificity. Therefore, comparing the sensitivities of these tests is probably more applicable towards ED management than the C-statistic composite
“The HEART score provides the clinician with a quick and reliable predictor of outcome, without computer-required calculating. Low HEART scores (0–3), exclude short-term MACE with >98% certainty. In these patients one might consider reserved policies. In patients with high HEART scores (7–10) the high risk of MACE may indicate more aggressive policies.”
In this observational cohort stufy, the HEART score more accurately identifies a low risk group of ED chest pain patients in comparison to either the TIMI or GRACE scores Further external validation studies examining the score in various populations would be beneficial
Potential Impact To Current Practice
Clinicians should consider adoption of the HEART score over TIMI or GRACE for chest pain risk stratification. Since this study, additional external validation studies have been performed (including the HEART pathway) demonstrating the utility of this tool.
The HEART score appears to be a superior clinical decision tool for risk stratification of chest pain patients in the ED when compared to the TIMI and GRACE scores.