Short-term risk after initial observation for chest pain

The HEART score is useful to predict cardiovascular risks and reduces unnecessary cardiac imaging in low-risk patients with acute chest pain

The present study was to investigate whether the HEART score can be used to evaluate cardiovascular risks and reduce unnecessary cardiac imaging in China.Acute coronary syndrome patients with the thrombosis in myocardial infarction risk score < 2 were enrolled in the emergency department. Baseline data were collected and a HEART score was determined in each participant during the indexed emergency visit. Participants were follow-up for 30 days after discharge and the studied endpoints included acute myocardial infarction, cardiovascular mortality and all-cause mortality.A total of 244 patients were enrolled and 2 was loss of follow-up. The mean age was 50.4 years old and male patients accounted for 64.5%. Substernal pain and featured as pressure of the pain accounted for 34.3% and 39.3%, respectively. After 30 days' follow-up, no patient in the low-risk HEART score group and 2 patients (1.5%) in the high risk HEART score group had cardiovascular events. The sensitivity of HEART score to predict cardiovascular events was 100% and the specificity was 46.7%. The potential unnecessary cardiac testing was 46.3%. Cox proportional hazards regression analysis showed that per one category increase of the HEART score was associated with nearly 1.3-fold risk of cardiovascular events.In the low-risk acute chest pain patients, the HEART score is useful to physicians in evaluating the risk of cardiovascular events within the first 30 days. In addition, the HEART score is also useful in reducing the unnecessary cardiac imaging.

Performance of highly sensitive cardiac troponin T assay to detect ischaemia at PET-CT in low-risk patients with acute coronary syndrome: a prospective observational study

BACKGROUND

Highly sensitive troponin T (hs-TnT) assay has improved clinical decision-making for patients admitted with chest pain. However, this assay's performance in detecting myocardial ischaemia in a lowrisk population has been poorly documented.

PURPOSE

To assess hs-TnT assay's performance to detect myocardial ischaemia at positron emission tomography/CT (PET-CT) in low-risk patients admitted with chest pain.

METHODS

Patients admitted for chest pain with a nonconclusive ECG and negative standard cardiac troponin T results at admission and after 6 hours were prospectively enrolled. Their hs-TnT samples were at T0, T2 and T6. Physicians were blinded to hs-TnT results. All patients underwent a PET-CT at rest and during adenosine-induced stress. All patients with a positive PET-CT result underwent a coronary angiography.

RESULTS

Forty-eight patients were included. Six had ischaemia at PET-CT. All of them had ≥1 significant stenosis at coronary angiography. Areas under the curve (95% CI) for predicting significant ischaemia at PET-CT using hs-TnT were 0.764 (0.515 to 1.000) at T0, 0.812(0.616 to 1.000) at T2 and 0.813(0.638 to 0.989) at T6. The receiver operating characteristicbased optimal cut-off value for hs-TnT at T0, T2 and T6 needed to exclude significant ischaemia at PET-CT was <4 ng/L. Using this value, sensitivity, specificity, positive and negative predictive values of hs-TnT to predict significant ischaemia were 83%/38%/16%/94% at T0, 100%/40%/19%/100% at T2 and 100%/43%/20%/100% at T6, respectively.

CONCLUSIONS

Our findings suggest that in low-risk patients, using the hs-TnT assay with a cut-off value of 4 ng/L demonstrates excellent negative predictive value to exclude myocardial ischaemia detection at PET-CT, at the expense of weak specificity and positive predictive value.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Identifier: NCT01374607.

Best Clinical Practice: Current Controversies in Evaluation of Low-Risk Chest Pain-Part 1

BACKGROUND

Chest pain is a common presentation to the emergency department (ED), though the majority of patients are not diagnosed with acute coronary syndrome (ACS). Many patients are admitted to the hospital due to fear of ACS.

OBJECTIVE

Our aim was to investigate controversies in low-risk chest pain evaluation, including risk of missed ACS, stress test, and coronary computed tomography angiography (CCTA).

DISCUSSION

Chest pain accounts for 10 million ED visits in the United States annually. Many patients are at low risk for a major cardiac adverse event (MACE). With negative troponin and nonischemic electrocardiogram (ECG), the risk of MACE and myocardial infarction (MI) is < 1%. The American Heart Association recommends further evaluation in low- to intermediate-risk patients within 72 h. These modalities add little to further risk stratification. These evaluations do not appropriately risk stratify patients who are already at low risk, nor do they diagnose acute MI. CCTA is an anatomic evaluation of the coronary vasculature with literature support to decrease ED length of stay, though it is associated with downstream testing. Literature is controversial concerning further risk stratification in already low-risk patients.

CONCLUSIONS

With nonischemic ECG and negative cardiac biomarker, the risk of ACS approaches < 1%. Use of stress test and CCTA for risk stratification of low-risk chest pain patients is controversial. These tests may allow prognostication but do not predict ACS risk beyond ECG and troponin. CCTA may be useful for intermediate-risk patients, though further studies are required.

Compliance with stress testing in patients discharged from the emergency department following a diagnosis of low-risk chest pain

OBJECTIVE

To determine rates of compliance with outpatient stress testing in patients with a diagnosis of low-risk chest pain, reasons for non-compliance and incidence of adverse cardiac events (ACE).

METHODS

This was a prospective study of 79 patients who were discharged from the emergency department with low-risk chest pain. Patients were followed-up by phone interview.

RESULTS

36.7% of patients completed EST within 30 days, 2.5% of patients completed their EST within the recommended 72 h. A lack of time was the most common reason for non-compliance and was seen in 32.0% of patients. 20% of ESTs were cancelled by the primary care physician (PCP). 12% of patients were non-compliant, as they believed the pain to be non-cardiac. There were no documented ACEs in the study.

CONCLUSIONS

Compliance with EST is poor in patients with low-risk chest pain. Non-compliance is related to a number of factors including work commitments, cancellation of studies by the PCP and patients beliefs about the nature of their chest pain.

Compliance with outpatient stress testing in low-risk patients presenting to the emergency department with chest pain

Recent evidence suggests that stress testing prior to emergency department (ED) release in low-risk chest pain patients identifies those who can be safely discharged home. When immediate stress testing is not feasible, rapid outpatient stress testing has been recommended. The objective of this study was to determine compliance rate and incidence of adverse cardiac events in patients presenting to the ED with low-risk chest pain referred for outpatient stress testing. Retrospective chart and social security death index review were conducted in 448 consecutive chest pain patients who presented to a university hospital and level I trauma center between April 30 and December 31, 2007. Patients were evaluated with an accelerated chest pain protocol defined as a 4-hour ED rule out and referral for outpatient stress testing within 72 hours of ED release. Only patients without known cardiac disease, a thrombolysis in myocardial infarction risk score ≤2, negative serial ECGs and cardiac biomarkers, and benign ED course were eligible for the protocol. Primary outcome measures included compliance with outpatient stress testing and documented 30-day incidence of adverse cardiac events following ED release. The social security death index was queried to determine 12-month incidence of all-cause mortality in enrolled patients. Logistic regression analysis of characteristics associated with outpatient stress test compliance was determined and incidence of adverse cardiac events in those who were and were not compliant with outpatient stress testing was compared. Significance was set at P < 0.05. A total of 188 patients (42%) completed outpatient stress testing, but only 27 (6%) completed testing within 72 hours of ED discharge. Compliance was correlated with insurance and race, but not patient age, gender, or thrombolysis in myocardial infarction risk score. No significant differences in adverse cardiac events were documented in patients who did and did not comply with outpatient stress testing. Compliance with outpatient stress testing is poor in low-risk chest pain patients following ED release. Despite poor compliance, the documented incidence of adverse cardiac events in this low-risk cohort was lower than that reported in patients with negative provocative testing prior to ED release.

Testing of low-risk patients presenting to the emergency department with chest pain: a scientific statement from the American Heart Association

The management of low-risk patients presenting to emergency departments is a common and challenging clinical problem entailing 8 million emergency department visits annually. Although a majority of these patients do not have a life-threatening condition, the clinician must distinguish between those who require urgent treatment of a serious problem and those with more benign entities who do not require admission. Inadvertent discharge of patients with acute coronary syndrome from the emergency department is associated with increased mortality and liability, whereas inappropriate admission of patients without serious disease is neither indicated nor cost-effective. Clinical judgment and basic clinical tools (history, physical examination, and electrocardiogram) remain primary in meeting this challenge and affording early identification of low-risk patients with chest pain. Additionally, established and newer diagnostic methods have extended clinicians' diagnostic capacity in this setting. Low-risk patients presenting with chest pain are increasingly managed in chest pain units in which accelerated diagnostic protocols are performed, comprising serial electrocardiograms and cardiac injury markers to exclude acute coronary syndrome. Patients with negative findings usually complete the accelerated diagnostic protocol with a confirmatory test to exclude ischemia. This is typically an exercise treadmill test or a cardiac imaging study if the exercise treadmill test is not applicable. Rest myocardial perfusion imaging has assumed an important role in this setting. Computed tomography coronary angiography has also shown promise in this setting. A negative accelerated diagnostic protocol evaluation allows discharge, whereas patients with positive findings are admitted. This approach has been found to be safe, accurate, and cost-effective in low-risk patients presenting with chest pain.

Serial hematocrit testing does not identify major injuries in trauma patients in an observation unit

BACKGROUND

Routine serial hematocrit measurements are a component of the trauma evaluation for patients without serious injury identified on initial evaluation. We sought to determine whether serial hematocrit testing was useful in detecting significant intra-abdominal injuries in trauma patients in our observation unit.

METHODS

We performed a retrospective chart review of all trauma patients placed in our observation unit over a 14-month period. Patients had received trauma surgery evaluation before placement in the observation unit and routinely received serial hematocrit testing (>or=2 hematocrit levels) while in the observation unit. We compared trauma patients with a hematocrit drop of 5 points or more to those without a significant hematocrit drop.

RESULTS

Three hundred sixty-five trauma patients were placed in the observation unit, and 310 patients (85%) had at least 2 hematocrits drawn during their stay. Of these patients, 20.6% had a hematocrit drop of 5 or more. Of patients with the hematocrit change, 18.8% were admitted to an inpatient unit from the observation unit compared to 9.3% of patients without a significant hematocrit change (P = .034). In one of these patients who had a computed tomography scan before observation admission, which demonstrated free fluid, the hematocrit drop assisted in diagnosing significant intra-abdominal injury.

CONCLUSION

Although serial hematocrit testing may be useful in specific situations, routine use of serial hematocrit testing in trauma patients at a level I trauma center's observation unit did not significantly aid in the detection of occult injury.

The use of exercise stress testing for the management of low-risk patients with chest pain

OBJECTIVE

This retrospective study assessed the contribution of exercise stress testing (EST) in the evaluation of patients with low risk for coronary heart disease who presented to the emergency department (ED) with chest pain.

BASIC PROCEDURES

The study included 175 patients who presented to the ED with chest pain and underwent EST between January 1, 2005, and November 30, 2006.

MAIN FINDINGS

After the EST, 113 patients were discharged, and 62 were admitted. Exercise stress testing's positive predictive value for coronary artery disease among admitted patients was 35.7%, and sensitivity was 95.2%. Exercise stress testing's negative predictive value among discharged patients was 99.1%. None of the 113 discharged patients returned to the ED for cardiac reasons during the 30-day follow-up period.

PRINCIPAL CONCLUSION

A chest pain unit or a parallel facility for evaluating patients with chest pain and with low risk for active coronary disease is necessary for detecting low-risk patients who eventually need cardiac intervention.

Usefulness of routine use of multidetector coronary computed tomography in the "fast track" evaluation of patients with acute chest pain

Recently published American Heart Association/American College of Cardiology guidelines suggest that multidetector computed tomography (MDCT) may be appropriate for investigating acute chest pain (ACP). Only a few small studies have evaluated the use of MDCT in ACP, where it was not part of routine investigation. We sought to evaluate the routine use of MDCT in a large cohort of patients presenting with ACP in a real-world setting. We studied 785 consecutive patients with ACP who underwent evaluation by MDCT or myocardial perfusion scintigraphy after an observation period of > or = 12 hours. Patients with findings suggestive of significant coronary artery disease (CAD) were referred to coronary angiography. Forty-two patients were hospitalized due to evidence of myocardial ischemia and 44 patients were discharged after the observation period. Of the remaining 699 patients, 340 underwent MDCT and 359 myocardial perfusion scintigraphy. In 22 patients (7%) multidetector computed tomogram showed significant CAD and in 32 (9%) patients myocardial perfusion scintigram showed significant ischemia. Significant CAD was confirmed by coronary angiography in 65% and 60%, respectively. Multidetector computed tomogram was nondiagnostic in 31 patients (9%). Extracardiac findings that might be related to ACP and/or necessitated further investigation were demonstrated by multidetector computed tomogram in 71 patients (21%). During 3-month follow-up, 1 patient (0.3%) with negative multidetector computed tomographic and 9 (3%) with negative myocardial perfusion scintigraphic findings developed an acute coronary syndrome or died. Rehospitalization, due to recurrent chest pain, occurred in 9 patients (3.3%) and 21 patients (7.2%), respectively. In conclusion, MDCT could be an appropriate alternative to traditional noninvasive techniques for investigating ACP.

Impact of a negative prior stress test on emergency physician disposition decision in ED patients with chest pain syndromes

OBJECTIVE

Many emergency department (ED) patients with potential acute coronary syndromes (ACS) have prior visits and prior cardiac testing; however, the effect of knowledge of prior testing on the emergency physician disposition decision making is not known. We studied the impact of prior noninvasive testing (ie, stress testing) for myocardial ischemia on disposition decision making in ED patients with potential ACS.

METHODS

We performed a prospective cohort study of ED patients with chest pain who received an electrocardiogram for potential ACS. Data included demographics, medical history, stress test history, and TIMI risk score. Patients were followed in-house; 30-day telephone interviews were performed for follow-up. Main outcomes were ED disposition (admit/discharge) and a composite of 30-day death, acute myocardial infarction, and revascularization stratified on the basis of prior stress testing known at the time of presentation. Standard statistical techniques were used with 95% confidence intervals (CI).

RESULTS

There were 1853 patients enrolled and 97% had follow-up. Patients had a mean age of 53 +/- 14 years; 60% were women, 67% were black. There were 1491 (79%) patients without a prior stress test, 291 (16%) had a normal prior stress test result, and 89 (5%) had an abnormal prior stress test result. Admission rates were 92% (95% CI, 87%-98%) for patients with a prior abnormal stress test, 73% (95% CI, 67%-78%) for patients with a normal prior stress test, and 70% (95% CI, 67%-72%) for patients without a prior stress test. Adverse outcomes were the highest among patients with prior abnormal stress test but did not differ significantly between patients with no prior stress test and patients with prior normal stress test (10.1% [95% CI, 3.6-16.7%] vs 5.2% [95% CI, 4.1-6.4%] vs 4.8% [95% CI, 2.4-7.3%]).

CONCLUSION

Patients without prior stress tests and patients with prior normal stress tests were admitted for potential ACS at the same rate and had the same 30-day cardiovascular event rates. This suggests that prior stress testing does not affect subsequent disposition decisions. Perhaps cardiac catheterization or computed tomography coronary angiograms would have more of an impact on subsequent visits, making them potentially more cost-effective in the low-risk patient.

A critical pathway for patients with acute chest pain and low risk for short-term adverse cardiac events: role of outpatient stress testing

STUDY OBJECTIVE

We evaluate the safety and feasibility of a critical care pathway protocol in which patients with acute chest pain who are low risk for coronary artery disease and short-term adverse cardiac outcomes receive outpatient stress testing within 72 hours of an emergency department (ED) visit.

METHODS

We performed an observational study of an ED-based chest pain critical pathway in an urban, community hospital in 979 consecutive patients. Patients enrolled in the protocol were observed in the ED before receiving 72-hour outpatient stress testing. The pathway was primarily analyzed for rates of death or myocardial infarction in the 6 months after ED discharge and outpatient stress testing. Secondary outcome measures included need for coronary intervention at initial stress testing and within 6 months after discharge, subsequent ED visits for chest pain, and subsequent hospitalization.

RESULTS

Of 871 stress-tested patients aged 40 years or older, who had low risk for coronary artery disease and short-term adverse cardiac events, and had 6-month follow-up, 18 (2%) required coronary intervention, 1 (0.1%) had a myocardial infarction within 1 month, 2 (0.2%) had a myocardial infarction within 6 months, 6 (0.7%) had normal stress test results after discharge but required cardiac catheterization within 6 months, and 5 (0.6%) returned to the ED within 6 months for ongoing chest pain. Hospital admission rates decreased significantly from 31.2% to 26.1% after initiation of the protocol (P<.001).

CONCLUSION

For patients with chest pain and low risk for short-term cardiac events, outpatient stress testing is feasible, safe, and associated with decreased hospital admission rates. With an evidence-based protocol, physicians efficiently identify patients at low risk for clinically significant coronary artery disease and short-term adverse cardiac outcomes.

Initial Evaluation of Chest Pain

Chest pain is among the most frequently evaluated presenting complaints in the emergency department (ED). Diagnostic etiologies range from benign to life-threatening. Failure to diagnose the life-threatening chest emergencies-specifically acute coronary syndrome, aortic dissection, and pulmonary embolism-can lead to catastrophic medical and legal outcomes for the patient and physician respectively. This article focuses on clinical and risk management strategies to minimize misdiagnosis and produce favorable medical and medicolegal outcomes.