What Is the HEART Score?
The HEART score is a clinical prediction tool developed by Dr. A. Jacob Six and colleagues in the Netherlands, first published in 2008. It was designed specifically to help emergency department physicians rapidly assess the risk of major adverse cardiac events (MACE) in patients presenting with chest pain. The acronym HEART stands for its five components: History, ECG, Age, Risk factors, and Troponin.
Chest pain is one of the most common reasons for emergency department visits worldwide, accounting for approximately 8 million visits annually in the United States alone. However, only a minority of these patients are actually experiencing an acute coronary syndrome (ACS). The HEART score provides a simple, evidence-based framework to identify which patients can be safely discharged and which require urgent intervention, reducing unnecessary admissions while ensuring high-risk patients receive appropriate care.
Unlike many cardiac risk scores that were developed for patients already diagnosed with ACS, the HEART score was specifically designed for the undifferentiated chest pain patient in the emergency department setting, making it uniquely practical for front-line clinicians.
Understanding MACE
Major Adverse Cardiac Events (MACE) is a composite endpoint commonly used in cardiovascular research and clinical practice. In the context of the HEART score, MACE within 6 weeks of presentation typically includes:
- Acute myocardial infarction (AMI): Heart attack, including both ST-elevation and non-ST-elevation myocardial infarction
- Percutaneous coronary intervention (PCI): Coronary angioplasty with or without stenting performed due to significant coronary artery disease
- Coronary artery bypass grafting (CABG): Surgical revascularization for multi-vessel or left main coronary artery disease
- All-cause death: Death from any cause within the follow-up period
The MACE rate is the primary outcome measure for the HEART score, with different risk categories corresponding to substantially different MACE rates within 6 weeks of the initial emergency department presentation.
HEART Score Components Explained
History (0-2 points)
The history component evaluates the clinical suspicion based on the patient's presenting symptoms. A highly suspicious history includes typical chest pain characteristics: substernal pressure or squeezing, radiation to the jaw, left arm, or both arms, association with diaphoresis (sweating) or nausea, and provocation by exertion with relief by rest or nitroglycerin. Moderately suspicious histories contain some typical features mixed with atypical elements. Slightly suspicious histories involve predominantly atypical features such as sharp, pleuritic, or positional chest pain.
ECG (0-2 points)
The electrocardiogram component assesses the initial ECG findings. A normal ECG receives 0 points. Non-specific repolarization disturbances, bundle branch blocks, left ventricular hypertrophy patterns, or pacemaker rhythms that prevent interpretation receive 1 point. Significant ST deviation (ST depression or elevation of 1 mm or more in two or more contiguous leads, not known to be pre-existing) receives 2 points.
Age (0-2 points)
Age is a powerful independent risk factor for coronary artery disease. Patients under 45 years receive 0 points, those aged 45 to 64 receive 1 point, and patients 65 years and older receive 2 points. This reflects the progressively increasing prevalence and severity of coronary artery disease with advancing age.
Risk Factors (0-2 points)
This component counts traditional cardiovascular risk factors: hypertension, hypercholesterolemia, diabetes mellitus, obesity (BMI > 30), current or recent smoking (< 90 days), and positive family history of coronary artery disease (first-degree relative with CAD before age 65 in women or 55 in men). No known risk factors = 0 points; 1–2 risk factors = 1 point; 3 or more risk factors, or history of known atherosclerotic disease (CAD, stroke, or peripheral vascular disease) = 2 points.
Troponin (0-2 points)
Initial troponin level is a critical component. Normal troponin (at or below the institutional upper limit of normal) = 0 points; 1–3 times the upper limit of normal = 1 point; greater than 3 times the upper limit of normal = 2 points. This applies to both conventional and high-sensitivity troponin assays, though the specific thresholds should be adjusted based on the assay used at the treating institution.
Score Interpretation and Risk Levels
| HEART Score | Risk Level | MACE Rate (6 weeks) | Recommended Action |
|---|---|---|---|
| 0 – 3 | Low risk | 1.7% | Consider early discharge with outpatient follow-up |
| 4 – 6 | Moderate risk | 12 – 16.6% | Admit for observation, serial troponins, non-invasive testing |
| 7 – 10 | High risk | 50 – 65% | Urgent invasive strategy (early coronary angiography) |
Clinical Use in the Emergency Department
The HEART score has become one of the most popular chest pain risk stratification tools in emergency medicine due to its simplicity and strong clinical performance. It can be calculated within minutes at the bedside without any specialized equipment beyond a standard ECG and troponin assay.
In practice, many emergency departments use the HEART score as part of an accelerated diagnostic protocol (ADP). Patients with a HEART score of 0–3 and two negative serial troponins (drawn at presentation and 3–6 hours later) may be candidates for early discharge with outpatient follow-up, potentially including a stress test within 72 hours. This approach has been shown to safely reduce admissions by 20–30% without missing clinically significant cardiac events.
For moderate-risk patients (score 4–6), admission for observation with serial troponin testing and further evaluation (e.g., coronary CT angiography, stress testing, or cardiology consultation) is generally recommended. High-risk patients (score 7–10) typically warrant urgent cardiology consultation and early invasive evaluation with coronary angiography.
HEART Score vs. TIMI Score
The Thrombolysis in Myocardial Infarction (TIMI) risk score is another widely used tool for assessing patients with chest pain. However, there are important differences between the two scores:
| Feature | HEART Score | TIMI Score |
|---|---|---|
| Target population | Undifferentiated chest pain in ED | Patients with suspected or confirmed UA/NSTEMI |
| Components | History, ECG, Age, Risk factors, Troponin | Age, Risk factors, Known stenosis, ASA use, Angina, ST changes, Biomarkers |
| Score range | 0 – 10 | 0 – 7 |
| Sensitivity for MACE | Higher (96–99% at score ≤ 3) | Lower (~95%) |
| Identifies safe discharges | Better (larger low-risk group) | Smaller low-risk group |
Multiple comparison studies have found that the HEART score outperforms the TIMI score in the emergency department setting, particularly in identifying low-risk patients suitable for early discharge. The HEART score also incorporates the clinical history component, which the TIMI score lacks, adding valuable clinical judgment to the scoring process.
Evidence and Validation
The HEART score has been validated in numerous studies across multiple countries and healthcare settings. Key evidence includes:
- Original derivation study (2008): Six et al. demonstrated that the HEART score effectively stratified chest pain patients into three distinct risk groups with significantly different MACE rates.
- HEART Pathway trial (2015): A randomized controlled trial by Mahler et al. showed that using the HEART score pathway reduced objective cardiac testing by 12%, reduced length of stay, increased early discharges by 21%, and was safe with no missed major adverse cardiac events at 30 days.
- HEART-FP study (2018): A large multicenter validation confirmed the safety of the HEART score for identifying low-risk patients, with a negative predictive value exceeding 99%.
- Meta-analyses: Multiple systematic reviews and meta-analyses including tens of thousands of patients have confirmed the HEART score's excellent diagnostic performance, with pooled sensitivity for MACE exceeding 96% at the low-risk threshold.
Current American College of Emergency Physicians (ACEP) guidelines support the use of the HEART score as a validated tool for chest pain risk stratification in the emergency department.
Frequently Asked Questions
What does a HEART score of 0 mean?
A HEART score of 0 indicates the lowest possible risk category. The patient has an atypical history, normal ECG, is under 45, has no risk factors, and a normal troponin. The estimated 6-week MACE rate for a score of 0–3 is approximately 1.7%. However, a score of 0 does not completely exclude cardiac disease, and clinical judgment should always be applied.
Can the HEART score be used for all chest pain patients?
The HEART score was designed for adult patients presenting to the emergency department with chest pain as a primary complaint. It should not be used for patients with clear STEMI on ECG (who require immediate intervention), patients with non-cardiac diagnoses already identified (e.g., pneumothorax, pulmonary embolism), or pediatric patients. It is most useful for the "gray zone" of undifferentiated chest pain.
How subjective is the History component?
The History component is the most subjective element of the HEART score. Studies have shown moderate inter-rater reliability for this component. To improve consistency, clinicians should focus on classic features of anginal chest pain: substernal location, provocation by exertion, and relief with rest or nitroglycerin. Atypical features include sharp pain, pleuritic pain, positional pain, and pain reproducible by palpation.
Should serial troponins change the HEART score?
The initial HEART score uses the first troponin result. If serial troponins rise, the HEART score should be recalculated with the updated troponin value. A rising troponin level may move a patient from the low-risk to moderate or high-risk category, changing the management approach accordingly.
Is the HEART score valid with high-sensitivity troponin assays?
Yes, the HEART score has been validated with both conventional and high-sensitivity troponin assays. When using high-sensitivity troponin, the institutional upper limit of normal (99th percentile) should be used as the reference for scoring. Some modifications to the troponin thresholds may be appropriate based on institutional protocols.