Short- and Long-Term Prognostic Utility of the HEART Score in Patients Evaluated in the Emergency Department for Possible Acute Coronary Syndrome

Pre-hospital rule-out of non-ST-segment elevation acute coronary syndrome by a single troponin: final one-year outcomes of the ARTICA randomised trial

BACKGROUND AND AIMS

The healthcare burden of acute chest pain is enormous. In the randomized ARTICA trial, we showed that pre-hospital identification of low-risk patients and rule-out of non-ST-segment elevation acute coronary syndrome (NSTE-ACS) with point-of-care (POC) troponin measurement reduces 30-day healthcare costs with low major adverse cardiac events (MACE) incidence. Here we present the final 1-year results of the ARTICA trial.

METHODS

Low-risk patients with suspected NSTE-ACS were randomized to pre-hospital rule-out with POC troponin measurement or emergency department (ED) transfer. Primary 1-year outcome was healthcare costs. Secondary outcomes were safety, quality of life (QoL), and cost-effectiveness. Safety was defined as a 1-year MACE consisting of ACS, unplanned revascularization, or all-cause death. QoL was measured with EuroQol-5D-5L questionnaires. Cost-effectiveness was defined as 1-year healthcare costs difference per QoL difference.

RESULTS

Follow-up was completed for all 863 patients. Healthcare costs were significantly lower in the pre-hospital strategy (€1932 ± €2784 vs. €2649 ± €2750), mean difference €717 [95% confidence interval (CI) €347 to €1087; P < 0.001]. In the total population, the 1-year MACE rate was comparable between groups [5.1% (22/434) in the pre-hospital strategy vs. 4.2% (18/429) in the ED strategy; P = 0.54]. In the ruled-out ACS population, 1-year MACE remained low [1.7% (7/419) vs. 1.4% (6/417)], risk difference 0.2% (95% CI -1.4% to 1.9%; P = 0.79). QoL showed no significant difference between strategies.

CONCLUSIONS

Pre-hospital rule-out of NSTE-ACS with POC troponin testing in low-risk patients is cost-effective, as expressed by a sustainable healthcare cost reduction and no significant effect on QoL. One-year MACE remained low for both strategies.

Use of the HEAR Score for 30-Day Risk-Stratification in Emergency Department Patients

BACKGROUND

The 2021 American College of Cardiology/American Heart Association chest pain guidelines recommend risk scores such as HEAR (History, Electrocardiogram, Age, Risk factors) for short-term risk stratification, yet limited data exist integrating them with high-sensitivity cardiac troponin T (hs-cTnT).

METHODS

Retrospective, multicenter (n = 2), observational, US cohort study of consecutive emergency department patients without ST-elevation myocardial infarction who had at least one hs-cTnT (limit of quantitation [LoQ] <6 ng/L, and sex-specific 99th percentiles of 10 ng/L for women and 15 ng/L for men) measurement on clinical indications in whom HEAR scores (0-8) were calculated. The composite major adverse cardiovascular event (MACE) outcome was 30-day prognosis.

RESULTS

Among 1979 emergency department patients undergoing hs-cTnT measurement, 1045 (53%) were low risk (0-3), 914 (46%) intermediate risk (4-6), and 20 (1%) high risk (7-8) based on HEAR scores. HEAR scores were not associated with increased risk of 30-day MACE in adjusted analyses. Patients with quantifiable hs-cTnT (LoQ-99th) had an increased risk for 30-day MACE (3.4%) irrespective of HEAR scores. Those with serial hs-cTnT <99th percentile remained at low risk (range 0%-1.2%) across all HEAR score strata. Higher scores were not associated with long-term (2-year) events.

CONCLUSIONS

HEAR scores are of limited value in those with baseline hs-cTnT 99th percentile to define short-term prognosis. In those with baseline quantifiable hs-cTnT within the reference range (<99th percentile), a higher risk (>1%) for 30-day MACE exists even in those with low HEAR scores. With serial hs-cTnT measurements, HEAR scores overestimate risk when hs-cTnT remains <99th percentile.

Can ED chest pain patients with intermediate HEART scores be managed as outpatients?

PURPOSE

Current guidelines recommend hospital admission for patients who present to the emergency department (ED) with chest pain and are scored as intermediate risk for adverse outcomes based on the HEART score. While hospital admission for these patients allows for timely investigation and treatment, it is a resource-intensive process. This study examines whether intermediate HEART score patients can be safely managed on an outpatient basis through rapid access chest pain clinics.

METHODS

This retrospective observational study included all ED chest pain patients referred to rapid access clinics from January 2018 to April 2020 in Regina and Saskatoon, Saskatchewan. ED physician HEART scores were used in lieu of reviewer HEART scores when available. The primary outcome was the rate of major adverse coronary events (MACE), a composite measure of death, acute coronary syndrome, stroke, coronary angiography, and revascularization at 6 weeks in intermediate-risk patients. Secondary outcomes were the type of MACE, rate of MACE before rapid access clinic appointment and the most predictive component of the HEART score.

RESULTS

There were 1989 ED referrals, of which 817 were for intermediate-risk patients. 9.3% of intermediate-risk patients had a MACE at 6 weeks. MACE occurred before rapid access clinic follow-up in 1.1% of intermediate-risk patients, with coronary angiography being the most common MACE. Excluding coronary angiography, the risk of MACE before rapid access clinic follow-up was 0.7% in intermediate-risk patients. Components of the HEART score most predictive of MACE were troponin (OR 11.0, 95% CI: 3.7-32.3) and history (5.3, 95% CI: 2.4-11.8).

CONCLUSION

This study demonstrates that rapid access clinics are likely a safe alternative to admission for intermediate-risk chest pain patients and could reduce costly inpatient admissions for chest pain. With angiography excluded, MACE rates were well below the American College of Emergency Physicians cited 2% threshold.

The Value of Different Short-Term Risk Scoring Models in Predicting Long-Term Death of Acute Myocardial Infarction

Background and aims: To compare the value of three commonly used cardiovascular short-term risk scoring models, the GRACE score, TIMI score, and HEART score, in predicting the long-term prognosis of patients with acute myocardial infarction. Methods: The hospitalization data of patients who were hospitalized in West China Hospital of Sichuan University from 2011 to 2013 and diagnosed with acute myocardial infarction (AMI) were collected. The patients were scored by GRACE score, TIMI score, and HEART score. The long-term follow-up of patients was conducted until the end of January 2021. All-cause death and time of death of patients were confirmed by telephone follow-up, electronic medical record query, and household registration information. The predictive ability of different risk scores for long-term prognosis was compared according to the receiver operating characteristic (ROC) area under the curve (AUC), and the ability to distinguish patients with different risk levels was compared according to Kaplan−Meier survival curves. Results: The study ultimately included 2220 patients, with a median follow-up of 8 years and 454 (20.5%) deaths until the end of follow-up. Whether in ST-segment elevation myocardial infarction (STEMI) patients or non-ST-segment elevation myocardial infarction (NSTEMI) patients, the AUC value of the GRACE score (both AUC = 0.734) was significantly higher than the TIMI score (AUC = 0.675, p < 0.01; AUC = 0.665, p < 0.01) and HEART score (AUC = 0.632, p < 0.01; AUC = 0.611, p < 0.01) until the end of follow-up. In terms of risk stratification, the Kaplan−Meier survival curve shows that both THE GRACE score and TIMI score can distinguish AMI patients with different risk levels (p < 0.01), but the risk stratification ability of the HEART score in AMI patients was poor (p > 0.05). Conclusion: The GRACE risk score could represent a more accurate model to assess long-term death of acute myocardial infarction, but further studies are required.

Utilizing machine learning dimensionality reduction for risk stratification of chest pain patients in the emergency department

BACKGROUND

Chest pain is among the most common presenting complaints in the emergency department (ED). Swift and accurate risk stratification of chest pain patients in the ED may improve patient outcomes and reduce unnecessary costs. Traditional logistic regression with stepwise variable selection has been used to build risk prediction models for ED chest pain patients. In this study, we aimed to investigate if machine learning dimensionality reduction methods can improve performance in deriving risk stratification models.

METHODS

A retrospective analysis was conducted on the data of patients > 20 years old who presented to the ED of Singapore General Hospital with chest pain between September 2010 and July 2015. Variables used included demographics, medical history, laboratory findings, heart rate variability (HRV), and heart rate n-variability (HRnV) parameters calculated from five to six-minute electrocardiograms (ECGs). The primary outcome was 30-day major adverse cardiac events (MACE), which included death, acute myocardial infarction, and revascularization within 30 days of ED presentation. We used eight machine learning dimensionality reduction methods and logistic regression to create different prediction models. We further excluded cardiac troponin from candidate variables and derived a separate set of models to evaluate the performance of models without using laboratory tests. Receiver operating characteristic (ROC) and calibration analysis was used to compare model performance.

RESULTS

Seven hundred ninety-five patients were included in the analysis, of which 247 (31%) met the primary outcome of 30-day MACE. Patients with MACE were older and more likely to be male. All eight dimensionality reduction methods achieved comparable performance with the traditional stepwise variable selection; The multidimensional scaling algorithm performed the best with an area under the curve of 0.901. All prediction models generated in this study outperformed several existing clinical scores in ROC analysis.

CONCLUSIONS

Dimensionality reduction models showed marginal value in improving the prediction of 30-day MACE for ED chest pain patients. Moreover, they are black box models, making them difficult to explain and interpret in clinical practice.

The HEART score as a prognostic tool for revascularization

The History, Electrocardiogram, Age, Risk Factors, Troponin (HEART) score is a useful tool in the Emergency Department setting to identify those patients safe for outpatient evaluation of chest pain. Its utility for predicting cardiac interventions is unclear. Our objective was to evaluate the prognostic accuracy of the HEART score to predict the need for cardiac stent or coronary artery bypass grafting (CABG). We conducted a retrospective chart review of 625 consecutive subjects with chest pain presenting to an Emergency Department (ED) with a HEART pathway protocol in place. We also reviewed each subject's record for evidence of major adverse cardiac events within 6 weeks following their ED visit. We double-abstracted 10% of the charts for quality assurance. We included subjects if they were ≥ 18 at the time of presentation and had a chief complaint of chest pain. We excluded subjects if they did not have an electrocardiogram or troponin, or if their chart lacked sufficient information to calculate the history portion of their HEART score. Of 625 charts, 449 subjects met criteria for study inclusion. The area under the receiver operator curve reported as c-statistics was 0.877 [95% confidence interval (CI) 0.806-0.949] for the HEART score's ability to predict cardiac stent and 0.921 (95% CI 0.858-0.984) for CABG. There is a strong association between increasing HEART scores and the need for revascularization which may provide emergency physicians justification for expedited cardiology consultation and admission for these patients. These findings require further prospective validation.

Incorporation of the HEART Score Into a Low-risk Chest Pain Pathway to Safely Decrease Admissions

Chest pain can be a challenging complaint to manage in the emergency department. A missed diagnosis can result in significant morbidity or mortality, whereas avoidable testing and hospitalizations can lead to increased health care costs, contribute to hospital crowding, and increase risks to patients. The HEART score is a validated decision aid to identify patients at low risk for acute coronary syndrome who can be safely discharged without admission or objective cardiac testing. In the largest and one of the longest studies to date (N = 31,060; 30 months), we included the HEART score into a larger, newly developed low-risk chest pain decision pathway, using a retrospective observational pre/post study design with the objective of safely lowering admissions. The modified HEART score calculation tool was incorporated in our electronic medical record. A significant increase in discharges of low-risk chest pain patients (relative increase of 21%; p < 0.0001) in the postimplementation period was observed with no significant difference in the rates of major adverse cardiac events between the pre and post periods. There was a decrease in the amount of return admissions for 30 days (4.65% fewer; p = 0.009) and 60 days (3.78% fewer; p = 0.020). No significant difference in length of stay was observed for patients who were ultimately discharged. A 64% decrease in monthly coronary computed tomography angiograms was observed in the post period (p < 0.0001). These findings support the growing consensus in the literature that the adoption of the HEART pathway or similar protocols in emergency departments, including at large and high-volume medical institutions, can substantially benefit patient care and reduce associated health care costs.

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

OBJECTIVE

The HEART score has been proposed for emergency department (ED) prediction of major adverse cardiac events (MACE). We sought to summarize all studies assessing the prognostic accuracy of the HEART score for prediction of MACE in adult ED patients presenting with chest pain.

METHODS

We searched MEDLINE, PubMed, EMBASE, Scopus, Web of Science, and the Cochrane Database of Systematic Reviews from inception through May 2018 and included studies using the HEART score for the prediction of short-term MACE in adult patients presenting to the ED with chest pain. The main outcome was short-term (i.e., 30-day or 6-week) incidence of MACE. We secondarily evaluated the prognostic accuracy of the HEART score for prediction of mortality and myocardial infarction (MI). Where available, accuracy of the Thrombolysis in Myocardial Infarction (TIMI) score was determined.

RESULTS

We included 30 studies (n = 44,202) in analysis. A HEART score above the low-risk threshold (≥4) had a sensitivity of 95.9% (95% confidence interval [CI] = 93.3%-97.5%) and specificity of 44.6% (95% CI = 38.8%-50.5%) for MACE. A high-risk HEART score (≥7) had a sensitivity of 39.5% (95% CI = 31.6%-48.1%) and specificity of 95.0% (95% CI = 92.6%-96.6%) for MACE, whereas a TIMI score above the low-risk threshold (≥2) had a sensitivity of 87.8% (95% CI = 80.2%-92.8%) and specificity of 48.1% (95% CI = 38.9%-57.5%) for MACE. A high-risk TIMI score (≥6) was 2.8% sensitive (95% CI = 0.8%-9.6%), but 99.6% (95% CI = 98.5%-99.9%) specific for MACE. A HEART score ≥ 4 had a sensitivity of 95.0% (95% CI = 87.2%-98.2%) for prediction of mortality and 97.5% (95% CI = 93.7%-99.0%) for prediction of MI.

CONCLUSIONS

The HEART score has excellent performance for prediction of MACE (particularly mortality and MI) in chest pain patients and should be the primary clinical decision instrument used for the risk stratification of this patient population.

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.

HEART Failure? Episodes of Missed Major Cardiac Events When Applying the HEART Pathway to an Observation Unit Population

OBJECTIVE

The HEART Pathway risk prediction tool (HEART score plus serial troponin measures at 0 and 3 hours post-presentation) is used to identify low-risk patients with chest pain who may qualify for safe, early discharge. We calculated the percentage of patients in our observation unit that qualified as low risk using HEART Pathway, as well as their associated outcomes.

METHODS

We retrospectively reviewed charts on 966 consecutive patients admitted to our observation unit for chest pain (January 2015 to February 2016); HEART Pathway scores were retrospectively calculated and serial cardiac troponin values logged. The primary outcome was 42-day major adverse cardiac events (MACE), including acute myocardial infarction, urgent revascularization, and all-cause death.

RESULTS

The patients' mean age was 59, 42% were male, 46% white, and 68 (7.7%) had MACE. HEART Pathway defined 384 patients as low risk (39.8%) and eligible for early discharge. Applying HEART Pathway would have missed 1.2% of patients with MACE; however, all adverse cardiac events occurred in patients with a HEART Pathway score of 3 (4 of 193, 2.1%) and none in those with a HEART Pathway score ≤2 (0 of 134).

CONCLUSIONS

While the HEART Pathway identifies a pooled population at low risk for MACE, risk is not homogenous within this population. Patients with a score of 3 may have higher risk of 42-day MACE that may be unacceptable to some providers, while scores ≤2 saw no events. Caution is advised for those with HEART Pathway score of 3 until more data is available to accurately estimate risk.

Clinical utility of the HEART score in patients admitted with chest pain to an inner-city hospital in the USA

BACKGROUND

Chest pain is one of the most common presentations to a hospital, and appropriate triaging of these patients can be challenging. The HEART score has been used for such purposes in some countries and only a few validation studies from the USA are available. We aim to determine the utility of the HEART score in patients presenting with chest pain to an inner-city hospital in the USA.

PATIENTS AND METHODS

We retrospectively screened 417 consecutive patients admitted with chest pain to the observation/telemetry units at Einstein Medical Center Philadelphia. After applying inclusion and exclusion criteria, 299 patients were included in the analysis. Patients were divided into low-risk (0-3) and intermediate-high (≥4)-risk HEART score groups. Baseline characteristics, thrombolysis in myocardial infarction score, need for revascularization during index hospitalization, and major adverse cardiovascular events (MACE) at 6 weeks and 12 months were recorded.

RESULTS

There were 98 and 201 patients in the low-score group and intermediate-high-score group, respectively. Compared with the low-score group, patients in the intermediate-high-risk group had a higher incidence of revascularization during the index hospital stay (16.4 vs. 0%; P=0.001), longer hospital stay, higher MACE at 6 weeks (9.5 vs. 0%) and 12 months (20.4 vs. 3.1%), and higher cardiac readmissions. HEART score of at least 4 independently predicted MACE at 12 months (odds ratio 7.456, 95% confidence interval: 2.175-25.56; P=0.001) after adjusting for other risk factors in regression analysis.

CONCLUSION

HEART score of at least 4 was predictive of worse outcomes in patients with chest pain in an inner-city USA hospital. If validated in multicenter prospective studies, the HEART score could potentially be useful in risk-stratifying patients presenting with chest pain in the USA and could impact clinical decision-making.

Efficacy of Implementation of a Chest Pain Center at a Community Hospital

INTRODUCTION

Chest pain is the second leading cause for emergency department (ED) visits in the United States; however, <20% of the patients have acute coronary syndrome that require immediate attention. The HEART score is designed for rapid risk stratification of ED chest pain patients using the following criteria: history, electrocardiogram, age, risk factors, and troponin. It has been shown to be superior in identifying patients with low (HEART score 0-3) and high (7-10) risk of major adverse cardiac events, who can then be rapidly discharged or admitted for intervention.

OBJECTIVE

This retrospective review and assessment sought to evaluate the efficacy of implementation of a Chest Pain Center (CPC) at a predominantly Asian-based community hospital in the United States. Additionally, this assessment sought to evaluate the effectiveness and safety of a HEART protocol in the first 4 months after its adoption.

MATERIALS AND METHODS

The facility implemented the CPC, an observation unit, in October 2016. ED physicians risk stratified patients using the HEART score. The guidelines allow ED physicians to stratify patients into 3 categories: to discharge low-risk patients, observe moderate-risk patients in the CPC, and admit high-risk patients. Patients in the CPC received additional diagnostic work-up under the care of ED physicians and cardiologists for less than 24 hours. In addition, CPC patients were followed-up 2 and 30 days after discharge.

RESULTS

A total of 172 patients presented at the ED with a chief complaint of chest pain. The majority of the patients were classified into the moderate-risk group (n = 101). Low-risk patients spent significantly less hours in the hospital than the moderate- and high-risk groups, and the high-risk group spent more time in the hospital than the moderate-risk group. The staff followed-up with 74 CPC patients through telephone calls to assess if patients were still experiencing chest pain and if they had followed-up with a cardiologist or primary care physician. The 2- and 30-day survival rates were 100% and 97%, respectively.

DISCUSSION

The data showed a significant reduction in total length of stay for all chest pain patients. This retrospective program evaluation demonstrated some evidence in using HEART score to safely risk stratify chest pain patients to the appropriate level of care. As healthcare moves from a fee-for-service environment to value-based purchasing, hospitals need to devise and implement innovative strategies to provide efficient, beneficial, and safe care for the patients.