Stress testing before discharge is not required for patients with low and intermediate risk of acute coronary syndrome after emergency department short stay assessment

Emergency Department Referral of Patients With Chest Pain for Noninvasive Cardiac Testing and 2-Year Clinical Outcomes

BACKGROUND

Noninvasive cardiac testing (NICT) has been associated with decreased long-term risks of major adverse cardiac events (MACEs) among emergency department patients at high coronary risk. It is unclear whether this association extends to patients without evidence of myocardial injury on initial ECG and cardiac troponin testing.

METHODS

A retrospective cohort study was conducted of patients presenting with chest pain between 2013 and 2019 to 21 emergency departments within an integrated health care system in Northern California, excluding patients with ST-segment-elevation myocardial infarction or myocardial injury by serum troponin testing. To account for confounding by indication, we grouped patient encounters by the NICT referral rate of the initially assigned emergency physician relative to local peers within discrete time periods. The primary outcome was MACE within 2 years. Secondary outcomes were coronary revascularization and MACE, inclusive of all-cause mortality. Associations between the NICT referral group (low, intermediate, or high) and outcomes were assessed using risk-adjusted proportional hazards methods with censoring for competing events.

RESULTS

Among 144 577 eligible patient encounters, the median age was 58 years (interquartile range, 48-68) and 57% were female. Thirty-day NICT referral was 13.0%, 19.9%, and 27.8% in low, intermediate, and high NICT referral groups, respectively, with a good balance of baseline covariates between groups. Compared with the low NICT referral group, there was no significant decrease in the adjusted hazard ratio of MACE within the intermediate (adjusted hazard ratio, 1.08 [95% CI, 1.02-1.14]) or high (adjusted hazard ratio, 1.05 [95% CI, 0.99-1.11]) NICT referral groups. Results were similar for MACE, inclusive of all-cause mortality, and coronary revascularization, as well as subgroup analyses stratified by estimated risk (history, electrocardiogram, age, risk factors, troponin [HEART] score: percent classified as low risk, 48.2%; moderate risk, 49.2%; and high risk, 2.7%).

CONCLUSIONS

Increases in NICT referrals were not associated with changes in the hazard of MACE within 2 years following emergency department visits for chest pain without evidence of acute myocardial injury. These findings further highlight the need for evidence-based guidance regarding the appropriate use of NICT in this population.

Higher intensity of 72-h noninvasive cardiac test referral does not improve short-term outcomes among emergency department patients with chest pain

BACKGROUND

It is unclear whether referral for cardiac noninvasive testing (NIT) following emergency department (ED) chest pain encounters improves short-term outcomes.

METHODS

This was a retrospective cohort study of patients presenting with chest pain, without ST-elevation myocardial infarction or myocardial injury by serum troponin testing, between 2013 and 2019 to 21 EDs within an integrated health care system. We examined the association between NIT referral (within 72 h of the ED encounter) and a primary outcome of 60-day major adverse cardiac events (MACE). Secondary outcomes were 60-day MACE without coronary revascularization (MACE-CR) and 60-day all-cause mortality. To account for confounding by indication for NIT, we grouped patient encounters into ranked tertiles of NIT referral intensity based on the likelihood of 72-h NIT referral associated with the initially assigned emergency physician, relative to local peers and within discrete time periods. Associations between NIT referral-intensity tertile and outcomes were assessed using risk-adjusted multivariable logistic regression.

RESULTS

Among 210,948 eligible patient encounters, 72-h NIT referral frequency was 11.9%, 18.3%, and 25.9% in low, intermediate, and high NIT referral-intensity encounters, respectively. Compared with the low referral-intensity tertile, there was a higher risk of 60-day MACE within the high referral-intensity tertile (odds ratio [OR] = 1.11, 95% confidence interval [CI] = 1.04 to 1.17) due to more coronary revascularizations without corresponding differences in MACE-CR or all-cause mortality. In analyses stratified by patients' estimated risk (HEART score; 50.5% lower risk, 38.7% moderate risk, 10.8% higher risk), the difference in 60-day MACE was primarily attributable to moderate-risk encounters (OR = 1.15, 95% CI = 1.08 to 1.24), with no differences among either lower- (OR = 1.10, 95% CI = 0.92 to 1.31) or higher- (OR = 1.01, 95% CI = 0.90 to 1.14) risk encounters.

CONCLUSION

Higher referral intensity for 72-h NIT was associated with higher risk of coronary revascularization but no difference in adverse events within 60 days. These findings further call into question the urgency of NIT among ED patients without objective evidence of myocardial injury.

Received care compared to ADP-guided care of patients admitted to hospital with chest pain of possible cardiac origin

Purpose

To assess the extent to which accelerated diagnostic protocols (ADPs), compared to traditional care, identify patients presenting to emergency departments (EDs) with chest pain who are at low cardiac risk and eligible for early ED discharge.

Patients and methods

Retrospective study of 290 patients admitted to hospital for further evaluation of chest pain following negative ED workup (no acute ischemic electrocardiogram [ECG] changes or elevation of initial serum troponin assay). Demographic data, serial ECG and troponin results, Thrombolysis in Myocardial Infarction (TIMI) score, cardiac investigations, and outcomes (confirmed acute coronary syndrome [ACS] at discharge and major adverse cardiac events [MACEs]) over 6 months of follow-up were analyzed. A validated ADP (ADAPT-ADP) was retrospectively applied to the cohort, and processes and outcomes of ADP-guided care were compared with those of care actually received.

Results

Patients had mean (±SD) TIMI score of 1.8 (±1.7); six (2.0%) patients were diagnosed with ACS at discharge. At 6 months, one patient (0.3%) re-presented with ACS and two (0.6%) died of non-coronary causes. The ADAPT-ADP defined 97 (33.4%) patients as being at low risk and eligible for early ED discharge, but who instead incurred mean hospital stay of 1.5 days, with 40.2% in telemetry beds, and 21.6% subject to non-invasive testing with only one positive result for coronary artery disease. None had a discharge diagnosis of ACS or developed MACE at 6 months.

Conclusion

Compared to traditional care, application of the ADAPT-ADP would have allowed one-third of chest pain patients with initially negative investigations in ED to have been safely discharged from ED.

Effectiveness of 2-hour Troponin in High-risk Patients With Suspected Acute Coronary Syndrome

BACKGROUND

Research has shown the safety and effectiveness of drawing a standard troponin level at presentation and again at 2 hours in only low-risk patients. Because high-sensitivity troponins are not currently approved in the United States, we studied the utility of a standard troponin that is presently in use. Our goal was to determine if 2-hour standard troponin would be safe and effective in the evaluation of a high-risk cohort of patients never studied previously.

METHODS

We conducted a single-center prospective observational study of adult patients presenting to the emergency department with signs and symptoms suggestive of acute coronary syndrome. Patients were defined as high risk if the attending physician planned to admit or transfer the patient to the observation unit. History, Electrocardiography, Age, Risk factors, Troponin scores were calculated on all patients to provide verification that the individuals were high risk. The primary outcome was a composite of 30-day myocardial infarction, death, cardiac arrest with return of spontaneous circulation, or dysrhythmia. The secondary outcome was 30-day revascularization.

RESULTS

We included a total of 122 patients with an average follow-up of 112 days (minimum 30 days). A total of 86% of cases had History, Electrocardiography, Age, Risk factors, Troponin scores ≥4. The primary outcome was met in 22 (18%) patients, and the secondary outcome occurred in 7 (5.7%) patients. The negative predictive value of negative 2-hour troponins along with no significant delta troponin rise was 98.7%.

CONCLUSIONS

Discharging patients thought to be high risk who have negative troponins at 0 and 2 hours and no delta troponin rise appears safe. No deaths occurred in follow-up. Larger studies are warranted.

Out-of-hours exercise treadmill testing reduces length of hospital stay for chest pain admissions

AIMS

The objective was to examine the impact of out-of-hours exercise treadmill tests (ETTs) on length of hospital stay (LOS) for patients admitted to a chest pain assessment unit with symptoms suggestive of acute coronary syndrome.

METHODS

Prospective observational study with 30-day follow-up of low-to-intermediate-risk chest pain patients undergoing out-of-hours ETT. Eligible patients had a nonischemic ECG, normal 6-12-h ST-segment monitoring, a negative 12-h troponin T assay, and no contraindications to exercise. Observed LOS was compared to expected LOS in the absence of out-of-hours ETT, using Wilcoxon rank-sum test. Estimated bed day savings and major adverse events at 30 days after discharge were examined.

RESULTS

Four hundred and twenty-two patients with a mean age of 52 years (SD 13 years, 25-83 years) were evaluated. Fifty-two per cent (n = 221) were men; 66% (n = 279) had one or less cardiovascular risk factors; and 79% (n = 334) of the patients presented on a Friday or Saturday. ETT was performed on a weekend day in 86% (n = 363) of the patients, facilitating same-day discharges in 71% (n =  300). The median LOS (interquartile range) was 1 day (1, 2 days) for patients assessed with out-of-hours ETT. The expected median LOS (IQR) was 3 days (2, 4 days) (P < 0.05) in the absence of out-of-hours ETT. Each out-of-hours ETT was estimated to save a mean (SD, range) of 1.6 (0.6, 1-4) bed days. Thirty-day mortality and readmission rates were 0 and 0.2% (1 of 422), respectively.

CONCLUSION

The availability of out-of-hours ETT facilitates safe early discharge and reduced LOS for low-to-moderate-risk patients admitted with symptoms of acute coronary syndrome.

The efficacy and safety of a chest pain protocol for short stay unit patients: A one year follow-up

BACKGROUND

The Alfred Emergency Short Stay Unit initiated a chest pain protocol for patients presenting with chest pain to risk stratify for acute coronary syndrome (ACS). A 30-day follow-up of patients discharged with low-or-intermediate risk of ACS demonstrated no deaths or ACS.

AIMS

The purpose of this study was to evaluate the long-term safety of the chest pain protocol, a one year follow-up was undertaken.

METHODS

A questionnaire was designed for the one-year follow-up and it was administered via a telephone interview by emergency nurses to document adverse cardiac events and health care utilisation.

RESULTS

From 297 patients, 224 (75%) were contacted 12 months following discharge. There was one death from stroke (0.4%; 95% confidence interval (CI): 0.01-2.5%) and another from an unknown cause. Five patients had been diagnosed with atrial fibrillation (2.2%; 95% CI: 0.7-5.1%), two patients had an acute myocardial infarction (0.9%; 95% CI: 0.03-2.1%) and four were diagnosed with angina (1.8%; 95% CI: 0.9-3.2%). Nearly half (n=103, 46%; 95% CI: 39.5-52.5%) had returned to the emergency department (ED) for various conditions including 42 patients with further chest pain. Ninety-six patients (43%; 95% CI: 39.3-52.7%) had specialist referrals and 124 investigations were performed. Thirty-four patients had cardiology referrals (15%; 95% CI: 10.7-20.5%) and 25 patients had gastroenterology referrals (11%; 95% CI: 7.3-16.0%). Diagnostic cardiac tests were performed on 38 patients: coronary angiography (n=10), 24-hour Holter monitoring (n=17), 24-hour blood pressure (BP) monitoring (n=4), thallium scans (n=5), exercise stress test (n=1) and CT scan (n=1).

CONCLUSION

Patients had a low risk of adverse events 12 months after discharge but substantial continuing health care utilization was observed. Complete assessment by health care professionals prior to discharge may help mitigate representations.

A cohort study of chest pain patients discharged from the emergency department for early outpatient treadmill exercise stress testing

OBJECTIVE

Guidelines on intermediate-risk chest pain, based on consensus alone, recommend inpatient provocative testing after infarct exclusion. Inpatient testing exceeds capacity in many hospitals, so guidelines concede outpatient testing within 72 h is acceptable. We performed a cohort study of chest pain patients having early outpatient treadmill exercise stress testing (EST).

METHODS

All chest pain patients discharged from our emergency with booked outpatient treadmill EST during the 2008 to 2010 calendar years were included. There were no exclusions. The primary outcome was diagnosis of major coronary artery disease among stress test attendees. Secondary outcomes were time to stress test booking, representations with chest pain or death within 30 days.

RESULTS

The cohort consisted of 657 patients: 59% men, mean age 53.2 years. Time from discharge to stress test averaged 10.6 days and 73% of patients attended. Of patients who attended, 14% had a positive test and 13% an inconclusive result. These patients were older than those with negative results (P < 0.001). Four patients (0.8% of attendees) were diagnosed with major coronary artery disease. There were no representations with acute myocardial infarction and no deaths identified.

CONCLUSIONS

Outpatient treadmill EST an average of 10 days post-discharge from emergency with chest pain did not result in adverse events despite reasonably high positive stress test rates. Consensus-based recommendations for inpatient testing or outpatient testing within 72 h of discharge should be reviewed in light of these data.

Improving stress testing compliance following chest pain presentations to the emergency department

OBJECTIVES

To determine whether a booked appointment time improves early outpatient exercise stress testing (EST) guideline adherence in patients discharged from the ED following assessment for possible acute coronary syndrome (ACS).

METHODS

In this pre and post study with a historical control group, patients classified as intermediate risk after negative ECG and serial troponin work-up for possible ACS were referred for EST. The intervention group were given an appointment time for EST at discharge, and the control group were given a referral but asked to book their own appointment. The primary outcome measure was the proportion in each group who attended for EST. Secondary outcomes were time to EST and rates of death, myocardial infarction and coronary revascularisation within 30 days in both groups. In addition, we explored reasons for non-attendance for EST for the intervention group.

RESULTS

There were 96 participants in the intervention group (mean age 55 ± 3 years) and 121 controls (mean age 62 ± 3 years). Seventy-two (75%) of the intervention group attended for EST compared with 38 (31%) of the control group, P < 0.001 after adjustment for differences in baseline variables. A poor understanding of the rationale for EST was a significant factor in patient non-attendance.

CONCLUSION

Pre-booked appointment times for EST improve timely attendance among patients discharged from the ED with intermediate-risk ACS. Compliance might improve further with patient education.