Clinical background
Acute chest pain is one of the commonest reasons for attending an emergency department, and a minority, under 10%, actually have an acute coronary syndrome. The clinical challenge is twofold: not to miss patients with myocardial infarction or unstable angina, and to avoid systematic over-triage with long stays, unnecessary objective cardiac testing and false positive findings that lead on to sometimes invasive investigations. The HEART Pathway was designed to solve exactly this problem: to identify, with a structured and reproducible instrument, the large proportion of patients who can be discharged early without risking that an acute coronary syndrome is overlooked.
Applying the HEART Pathway
The HEART score is the sum of five components, each scored 0 to 2:
where:
- = History: Slightly suspicious = 0, Moderately suspicious = 1, Highly suspicious = 2
- = ECG: Normal = 0, Non-specific repolarisation disturbance = 1, Significant ST-segment deviation = 2
- = Age: <45 years = 0, 45–64 years = 1, ≥65 years = 2
- = Risk factors: No known risk factors = 0, 1–2 risk factors = 1, ≥3 risk factors or known atherosclerotic disease = 2. The risk factors counted are hypertension, hypercholesterolaemia, diabetes, obesity (BMI >30), smoking (current or stopped <3 months ago), family history, and known atherosclerotic disease.
- = Initial troponin: ≤1× the upper limit of normal = 0, 1–3× the upper limit of normal = 1, >3× the upper limit of normal = 2
The total score ranges from 0 to 10. Low risk is defined as 0–3, moderate risk as 4–6, and high risk as 7–10.
The HEART Pathway is, however, more than the score itself. For a patient to be classified as low risk and suitable for early discharge, two conditions must be met: a HEART score of 0–3 and a troponin within the reference range at both 0 and 3 hours after arrival. The serial troponin protocol is therefore an integral part of the Pathway, not an addition to it.
The derivation cohort consisted of patients presenting with chest pain to Dutch emergency departments. The first large external validation was published by Six et al. in 2013 and comprised 2,906 patients at 14 hospitals in the Asia-Pacific region, with 30-day MACE (death, myocardial infarction or coronary revascularisation) as the outcome [1].
Interpretation in practice
| Risk band | HEART score | Troponin at 0 and 3 h | Recommended action |
|---|---|---|---|
| Low risk | 0–3 | Not raised at either time point | Early discharge from the emergency department without objective cardiac testing. Follow up in primary care. |
| Low risk | 0–3 | Raised at either time point | Must not be discharged. Continued investigation in an observation unit or on a ward. |
| Moderate risk | 4–6 | Whatever the result | Further investigation with objective cardiac testing (stress test, coronary angiography or equivalent) in an observation unit or on a ward. |
| High risk | 7–10 | Whatever the result | Inpatient care, cardiology consultation, early invasive strategy. |
It is important to note that a raised troponin at either measurement overrides the low-risk classification, however low the HEART score. The troponin component of the score assesses the initial level, but the Pathway protocol additionally requires the 3-hour value to be normal before discharge can be considered.
In the randomised HEART Pathway trial, use of the Pathway increased the proportion of early discharges from 18.4% to 39.7% compared with usual care, while the length of stay was shortened by an average of 12 hours (from 21.9 to 9.9 hours) and objective cardiac testing fell by 12.1 percentage points at 30 days [2]. None of the 105 patients identified for early discharge in the Pathway arm suffered a MACE within 30 days.
Validation and performance
In the multinational validation cohort of Six et al. (2,906 patients), the HEART score had a c-statistic of 0.83 (95% CI 0.81–0.85) for 30-day MACE, compared with 0.75 (95% CI 0.72–0.77) for the TIMI score [1]. The low-risk group (HEART ≤3) made up 28.2% of the cohort, with a false negative rate of 1.7% (14 of 820 patients). The high-risk group (HEART 7–10) made up 16% with a MACE rate of 43.1%.
A systematic review and meta-analysis by Fernando et al. in 2019, which included 30 studies with a total of 44,202 patients, summarised the overall evidence [3]. At the threshold of HEART ≥4, sensitivity for MACE was 95.9% (95% CI 93.3–97.5%) and specificity 44.6% (95% CI 38.8–50.5%). At the high-risk threshold of HEART ≥7, sensitivity was 39.5% and specificity 95.0%. Sensitivity for death was 95.0% and for myocardial infarction 97.5% at HEART ≥4. The review concluded that the HEART score has excellent prognostic performance and recommended it as the primary instrument for risk stratification of emergency department patients with chest pain.
In a comparative analysis of the HEART Pathway and ADAPT (a 2-hour accelerated diagnostic protocol based on TIMI) in 141 patients from the randomised trial, both instruments identified all patients with MACE as high risk (sensitivity 100%), but the HEART Pathway classified 47% of patients as low risk versus 24% for ADAPT, an absolute difference of 22.7 percentage points [4]. The HEART Pathway therefore reclassified almost twice as many patients for early discharge without losing sensitivity.
Limitations
Subjectivity of the history component. Judging how suspicious the history is (slightly, moderately or highly) is the least clearly defined component and the one that varies most between assessors. In the randomised trial, inter-observer agreement was measured by having an independent physician assign a second HEART score, and discrepancies were reported particularly for this component [2].
Developed with contemporary, not high-sensitivity, troponin assays. The HEART score and the HEART Pathway were validated with contemporary troponin assays. A retrospective study by Harris et al. in 1,014 patients found that when high-sensitivity troponin was used, a model with the ECG and high-sensitivity troponin alone had a c-statistic of 0.883 for ACS/MACE at 30 days, compared with 0.876 for the full HEART score [5]. Adding history, age and risk factors therefore did not improve discrimination. The authors argue that the HEART score has limited added value in the high-sensitivity troponin era, particularly for patients in the moderate risk group (HEART 4–6), in whom the ECG and troponin alone may suffice for a disposition decision. This observation is important but comes from a retrospective single-cohort study and needs prospective confirmation.
Excluded patients. The HEART Pathway does not apply to patients with ST elevation on the ECG, since these have an unequivocal STEMI and should be managed according to reperfusion guidelines, not risk-stratified. Nor does it apply to patients with haemodynamic instability or other clear indications for inpatient care.
The low-risk threshold and missed events. In the multinational validation, the false negative rate in the low-risk group was 1.7% [1]. In the randomised trial the rate was zero, but the cohort was small (105 early discharges) and the confidence interval for the true rate of missed MACE is therefore wide [2]. A sensitivity of 95.9% in the meta-analysis means that approximately 4 of every 100 patients with MACE may be classified as low risk if the HEART score is used without the serial troponin protocol [3]. This underlines the importance of following the Pathway protocol with troponin at both 0 and 3 hours consistently, and of never discharging a patient with a raised troponin at 3 hours whatever the score.
Single-centre RCT. The randomised trial was conducted at a single tertiary emergency hospital in North Carolina with trained emergency physicians and access to a wide range of cardiac testing modalities [2]. Generalisability to smaller hospitals or to health systems with different resources and routines is not established.
References
- Six AJ, Cullen L, Backus BE, et al. The HEART score for the assessment of patients with chest pain in the emergency department: a multinational validation study. Crit Pathw Cardiol 2013;12(3):121–6. PMID: 23892941
- Mahler SA, Riley RF, Hiestand BC, et al. The HEART Pathway randomized trial: identifying emergency department patients with acute chest pain for early discharge. Circ Cardiovasc Qual Outcomes 2015;8(2):195–203. PMID: 25737484
- Fernando SM, Tran A, Cheng W, et al. Prognostic accuracy of the HEART score for prediction of major adverse cardiac events in patients presenting with chest pain: a systematic review and meta-analysis. Acad Emerg Med 2019;26(2):140–151. PMID: 30375097
- Stopyra JP, Miller CD, Hiestand BC, et al. Chest pain risk stratification: a comparison of the 2-hour accelerated diagnostic protocol (ADAPT) and the HEART Pathway. Crit Pathw Cardiol 2016;15(2):46–49. PMID: 27183253
- Harris A, Heier K, Spindel JF, et al. The HEART score has less utility with high sensitivity troponin. Front Cardiovasc Med 2026;13:506365. PMID: 42534855
