Prognostic value of predischarge dobutamine stress echocardiography in chest pain patients with a negative cardiac troponin T

[Stress-Echocardiography in Low-risk Acute Coronary Syndrome Without Persistent ST-segment Elevation Diagnostic Algorithm]

This review addresses the capabilities of stress EchoCG as a simple, non-invasive, non-radiation method for diagnosing occult disorders of coronary blood flow in patients with non-ST-elevation acute coronary syndrome on a low-risk electrocardiogram. The capabilities of the enhanced stress EchoCG protocol are based on supplementing the standard detection of transient disturbances of local contractility, generally associated with coronary artery obstruction, with an assessment of the heart rate reserve, coronary reserve and other parameters. This approach is considered promising for a more complete characterization of heart function during exercise and an accurate prognosis of the clinical case, which allows determining the tactics for patient management not limited to selection for myocardial revascularization.

Clinical research progress of myocardial work in assessment and prediction of coronary artery disease in noninvasive pressure-strain loop technique

Early identification and treatment of high-risk coronary artery disease (CAD) is the main goal of current cardiovascular disease treatments. Speckle-tracking ultrasound technology can quantify myocardial work using pressure-strain loops. Because myocardial work takes into account the effect of the left ventricular systolic function afterload, it can more objectively reflect left ventricular myocardial mechanical function than the overall left ventricular longitudinal strain. Therefore, this technique is more widely used in diseases caused by CAD. This article reviews the evaluation and prediction of different CAD types using a variety of myocardial work parameters and provides a new method for clinical research to assess myocardial function, which is expected to become a new prediction method for CAD.

Major adverse cardiac events after emergency department evaluation of chest pain patients with advanced testing: Systematic review and meta-analysis

OBJECTIVES

Our primary objective was to describe the risk of major adverse cardiac events (MACE) at 1, 6, and 12 months after a negative coronary computed tomography angiogram (cCTA), electrocardiogram (ECG) stress test, stress echocardiography, and myocardial perfusion scintigraphy (MPS) in low- to intermediate-risk patients.

METHODS

Initially, 952 articles were identified for screening, 81 met criteria for full-text review, and once risk of bias was assessed, 33 articles were included in this meta-analysis. We utilized a random-effects model to assess pooled MACE event proportion for patients undergoing evaluation of acute coronary syndrome (ACS) when risk stratified to a low- to intermediate-risk category after undergoing standard testing. Heterogeneity analysis was performed using Cochrane's Q-test and I² statistic.

RESULTS

Twenty-one studies evaluated follow-up at 1 month with cCTA having a 0.09% (95% confidence interval [CI] = 0.03% to 0.26%) pooled MACE compared to 0.23% (95% CI = 0.01% to 5.8%) of the exercise stress testing (p = 1). MPS and cCTA had an overall event rate of 0.15% (95% CI = 0.06% to 0.41%) at 6 months (I²  = 0%). At 12 months, a subgroup analysis found a pooled cCTA MACE of 0.16% (95% CI = 0.04% to 0.65%) compared to 1.68% (95% CI = 0.01% to 2.6%) for stress echocardiography with low within-group heterogeneity (I²  = 0%). Subgroup analysis of cCTA with no disease versus nonobstructive disease (<50% stenosis) did not find statistical difference in the MACE at both 1 month (0.17% [95% CI = 0.04% to 0.67%] vs. 0.06% [95% CI = 0.01% to 0.34%]) and 12 months (0.44% [95% CI = 0.09% to 2.2% vs. 0.54% [95% CI = 0.19% to 1.5%]).

CONCLUSIONS

Patients presenting with chest pain who have a coronary CTA showing < 50% stenosis, negative ECG stress test, stress echocardiography, or stress myocardial perfusion scan in the past 12 months can be discharged without any further risk stratification if their ECG and troponin are reassuring given low MACE.

Non-invasive Imaging in Coronary Syndromes - Recommendations of the European Association of Cardiovascular Imaging and the American Society of Echocardiography, in Collaboration with the American Society of Nuclear Cardiology, Society of Cardiovascular Computed Tomography and Society for Cardiovascular Magnetic Resonance

Coronary artery disease (CAD) is one of the major causes of mortality and morbidity worldwide, with a high socioeconomic impact.(1) Non-invasive imaging modalities play a fundamental role in the evaluation and management of patients with known or suspected CAD. Imaging end-points have served as surrogate markers in many observational studies and randomized clinical trials that evaluated the benefits of specific therapies for CAD.(2) A number of guidelines and recommendations have been published about coronary syndromes by cardiology societies and associations, but have not focused on the excellent opportunities with cardiac imaging. The recent European Society of Cardiology (ESC) 2019 guideline on chronic coronary syndromes (CCS) and 2020 guideline on acute coronary syndromes in patients presenting with non-ST-segment elevation (NSTE-ACS) highlight the importance of non-invasive imaging in the diagnosis, treatment, and risk assessment of the disease.(3)(4) The purpose of the current recommendations is to present the significant role of non-invasive imaging in coronary syndromes in more detail. These recommendations have been developed by the European Association of Cardiovascular Imaging (EACVI) and the American Society of Echocardiography (ASE), in collaboration with the American Society of Nuclear Cardiology, the Society of Cardiovascular Computed Tomography, and the Society for Cardiovascular Magnetic Resonance, all of which have approved the final document.

HEART Pathway Implementation Safely Reduces Hospitalizations at One Year in Patients With Acute Chest Pain

STUDY OBJECTIVE

We determine whether implementation of the HEART (History, ECG, Age, Risk Factors, Troponin) Pathway is safe and effective in emergency department (ED) patients with possible acute coronary syndrome through 1 year of follow-up.

METHODS

A preplanned analysis of 1-year follow-up data from a prospective pre-post study of 8,474 adult ED patients with possible acute coronary syndrome from 3 US sites was conducted. Patients included were aged 21 years or older, evaluated for possible acute coronary syndrome, and without ST-segment elevation myocardial infarction. Accrual occurred for 12 months before and after HEART Pathway implementation, from November 2013 to January 2016. The HEART Pathway was integrated into the electronic health record at each site as an interactive clinical decision support tool. After integration, ED providers prospectively used the HEART Pathway to identify patients with possible acute coronary syndrome as low risk (appropriate for early discharge without stress testing or angiography) or nonlow risk (appropriate for further inhospital evaluation). Safety (all-cause death and myocardial infarction) and effectiveness (hospitalization) at 1 year were determined from health records, insurance claims, and death index data.

RESULTS

Preimplementation and postimplementation cohorts included 3,713 and 4,761 patients, respectively. The HEART Pathway identified 30.7% of patients as low risk; 97.5% of them were free of death and myocardial infarction within 1 year. Hospitalization at 1 year was reduced by 7.0% in the postimplementation versus preimplementation cohort (62.1% versus 69.1%; adjusted odds ratio 0.70; 95% confidence interval 0.63 to 0.78). Rates of death or myocardial infarction at 1 year were similar (11.6% versus 12.4%; adjusted odds ratio 1.00; 95% confidence interval 0.87 to 1.16).

CONCLUSION

HEART Pathway implementation was associated with decreased hospitalizations and low adverse event rates among low-risk patients at 1-year follow-up.

Utility of Physician Selection of Cardiac Tests in a Chest Pain Unit to Exclude Acute Coronary Syndrome Among Patients Without a History of Coronary Artery Disease

There are few data on the utility of physician selection of cardiac tests, including no-test, in a chest pain unit (CPU) to rule out acute coronary syndrome in low-risk patients without a history of coronary artery disease. We analyzed consecutive low-risk patients admitted to our CPU between 2012 and 2014 and determined the proportion of patients selected for testing, the type of initial cardiac test selected, and the incidence of major adverse cardiac events (MACEs) at 30 days and 6 months. The study group comprised 619 patients: mean age 57 years (27 to 92), 332 women (54%), and 360 (58%) with multiple cardiac risk factors. Cardiac testing included 283 no-test (46%); 179 exercise treadmill (29%); 113 myocardial perfusion stress scintigraphy (18%); <10% each for exercise stress echocardiography and coronary angiography. Testing was negative in 296 (88%), nondiagnostic in 30 (9%), and positive in 10 patients (3%). There were no MACEs at 30 days in any patients, and at 6 months, MACEs were 5 (1.1%). Length of stay was less in no-test than in tested patients (5.4 hours vs 9.8 hours, p <0.0001), and there was no difference in incidence of MACE at 6 months in no-test vs tested patients (2 MACEs vs 3 MACEs). Physician selection of cardiac tests, including no-test, promptly identified patients at low risk of acute coronary syndrome who could be safely and rapidly discharged from the CPU. Exclusion of cardiac testing shortened length of stay and was not associated with increase in MACE at 6 months.

Immediate Stress Echocardiography for Low-Risk Chest Pain Patients in the Emergency Department: A Prospective Observational Cohort Study

BACKGROUND

Evaluation and disposition of low-risk chest pain (CP) patients in the emergency department (ED) is time consuming and expensive. Low-risk CP often results in hospital admission to rule out myocardial infarction, which leads to additional costs and delays.

OBJECTIVE

Our aim was to assess whether an immediate exercise stress echocardiogram (IESE) in the ED will allow safe, efficient, and cost-effective evaluation and discharge of patients with low-risk CP.

METHODS

Low-risk CP patients (TIMI [Thrombolysis in Myocardial Infarction] score 0-1) presenting to the ED with normal electrocardiogram, no history of coronary artery disease, and negative troponin T received IESE. We followed these patients for major adverse cardiac events and compared them to a control cohort of similar-risk patients admitted with traditional care at 1 and 6 months.

RESULTS

We enrolled 216 patients, 117 IESE and 109 control. We obtained follow-up at 1 and 6 months in 94% of the IESE group and 88% in the control group. There was no difference in diagnostic catheterization or percutaneous coronary intervention between the 2 groups (6.0% and 1.7% vs. 6.4% and 1.8%; p = 0.89). Median time from triage to discharge was significantly shorter with IESE (572.6 min vs. 1466.0 min), resulting in significantly lower cost ($4380.50 vs. $6191.70). There were no adverse events related to IESE or early discharge.

CONCLUSIONS

In our study, IESE for low-risk CP patients presenting to the ED has the potential to be equally safe, more expeditious, and more cost effective than admission to an observation unit.

Cardiovascular Testing and Clinical Outcomes in Emergency Department Patients With Chest Pain

IMPORTANCE

Noninvasive testing and coronary angiography are used to evaluate patients who present to the emergency department (ED) with chest pain, but their effects on outcomes are uncertain.

OBJECTIVE

To determine whether cardiovascular testing-noninvasive imaging or coronary angiography-is associated with changes in the rates of coronary revascularization or acute myocardial infarction (AMI) admission in patients who present to the ED with chest pain without initial findings of ischemia.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort analysis used weekday (Monday-Thursday) vs weekend (Friday-Sunday) presentation as an instrument to adjust for unobserved case-mix variation (selection bias) between 2011 and 2012. National claims data (Truven MarketScan) was used. The data included a total of 926 633 privately insured patients ages 18 to 64 years who presented to the ED with chest pain without initial diagnosis consistent with acute ischemia.

EXPOSURES

Noninvasive testing or coronary angiography within 2 days or 30 days of presentation.

MAIN OUTCOMES AND MEASURES

The primary end points were coronary revascularization (percutaneous coronary intervention or coronary artery bypass graft surgery) and AMI admission at 7, 30, 180, and 365 days. The secondary end points were coronary angiography and coronary artery bypass grafting in those who underwent angiography.

RESULTS

The patients were ages 18 to 64 years with an average age of 44.4 years. A total of 536 197 patients (57.9%) were women. Patients who received testing (224 973) had increased risk at baseline and had greater risk of AMI admission than those who did not receive testing (701 660) (0.35% vs 0.14% at 30 days). Weekday patients (571 988) had similar baseline comorbidities to weekend patients (354 645) but were more likely to receive testing. After risk factor adjustment, testing within 30 days was associated with a significant increase in coronary angiography (36.5 per 1000 patients tested; 95% CI, 21.0-52.0) and revascularization (22.8 per 1000 patients tested; 95% CI, 10.6-35.0) at 1 year but no significant change in AMI admissions (7.8 per 1000 patients tested; 95% CI, -1.4 to 17.0). Testing within 2 days was also associated with a significant increase in coronary revascularization but no difference in AMI admissions.

CONCLUSIONS AND RELEVANCE

Cardiac testing in patients with chest pain was associated with increased downstream testing and treatment without a reduction in AMI admissions, suggesting that routine testing may not be warranted. Further research into whether specific high-risk subgroups benefit from testing is needed.

Noninvasive Testing in Emergency Department Patients with Low-Risk Chest Pain: Does the Evidence Support Current Guidelines?

Patients who present to the emergency department with chest pain but no evidence of ischemia on the electrocardiogram and negative cardiac markers are at very low risk. The newest American Heart Association/American College of Cardiology guidelines give noninvasive cardiac testing a IIa recommendation in this patient population. Here, we will review the existing literature that was cited in the American Heart Association/American College of Cardiology document, as well as several large, contemporary, comparative observational studies which were not included to address the following question: Do the benefits of noninvasive cardiac testing in this patient population outweigh the risks?

Echocardiography in the Emergency Department

In the busy emergency department, time-effective and accurate diagnostic and prognostic evaluation is essential Although clinical examination remains the mainstay of appropriate evaluation, remaining diagnostic uncertainty may need to be resolved by use of additional techniques. Echocardiography appears very well suited to the unique environment in the emergency department. It is portable to the patient's bedside, can be performed in minimal time, and results are immediately available. This facilitates correct triage and disposition of complicated cases. Small, hand-carried echocardiography systems have been developed with full imaging and Doppler capabilities. Thus, availability of echocardiography is increasing. Because both image acquisition and interpretation are operator-dependent, realization of full diagnostic potential requires extensive training and post-training experience to maintain proficiency.

Noninvasive cardiac imaging in suspected acute coronary syndrome

Noninvasive cardiac imaging has an important role in the assessment of patients with acute-onset chest pain. In patients with suspected acute coronary syndrome (ACS), cardiac imaging offers incremental value over routine clinical assessment, the electrocardiogram, and blood biomarkers of myocardial injury, to confirm or refute the diagnosis of coronary artery disease and to assess future cardiovascular risk. This Review covers the current guidelines and clinical use of the common noninvasive imaging techniques, including echocardiography and stress echocardiography, computed tomography coronary angiography, myocardial perfusion scintigraphy, positron emission tomography, and cardiovascular magnetic resonance imaging, in patients with suspected ACS, and provides an update on the developments in noninvasive imaging techniques in the past 5 years.

Chest pain: coronary CT in the ER

Cardiac CT has developed into a robust clinical tool during the past 15 years. Of the fields in which the potential of cardiac CT has raised more interest is chest pain in acute settings. In fact, the possibility to exclude with high reliability obstructive coronary artery disease (CAD) in patients at low-to-intermediate risk is of great interest both from the clinical standpoint and from the management standpoint. Several other modalities, with or without imaging, have been used during the past decades in the settings of new onset chest pain or in acute chest pain for both diagnostic and prognostic assessment of CAD. Each one has advantages and disadvantages. Most imaging modalities also focus on inducible ischaemia to guide referral to invasive coronary angiography. The advent of cardiac CT has introduced a new practice diagnostic paradigm, being the most accurate non-invasive method for identification and exclusion of CAD. Furthermore, the detection of subclinical CAD and plaque imaging offer the opportunity to improve risk stratification. Moreover, recent advances of the latest generation CT scanners allow combining both anatomical and functional imaging by stress myocardial perfusion. The role of cardiac CT in acute settings is already important and will become progressively more important in the coming years.

The incremental value of stress testing in patients with acute chest pain beyond serial cardiac troponin testing

OBJECTIVE

In patients with acute chest pain and normal range cardiac troponin (cTn), accurate risk stratification for acute coronary syndrome is challenging. This study assesses the incremental value of stress testing to identify patients for angiography with a view to revascularisation.

METHODS

A single-centre observational study recruited patients with acute chest pain in whom serial cTn tests were negative and stress testing (exercise tolerance testing/dobutamine stress echocardiography) was performed. Stress tests were reported as negative, non-diagnostic or positive. The primary outcomes were revascularisation on index admission, or cardiac death and myocardial infarction over 1 year follow-up.

RESULTS

Of 749 patients recruited, 709 underwent exercise tolerance testing and 40 dobutamine stress echo of which 548 (73.2%) were negative, 169 (22.6%) were non-diagnostic and 32 (4.3%) were positive. Patients with positive tests (n=19 (59.4%)) were more likely to undergo index admission revascularisation than patients with non-diagnostic (n=15 (8.9%)) (p<0.001) tests who in turn were more likely undergo index admission revascularisation than those with negative tests (n=2 (0.4%)) (p<0.001). The risks of adverse events including cardiovascular death/acute myocardial infarction were low and were similar across stress test outcomes.

CONCLUSIONS

The incremental value of stress testing was the identification of an additional 34 (4.5% (95% CI 3.0% to 6.0%)) patients who underwent index admission revascularisation with a view to preventing future adverse events. Uncertainty in whether revascularisation prevents adverse events in patients with negative cTn means the choice to undertake stress testing depends on whether clinicians perceive value in identifying 4.5% of these patients for revascularisation.

CLINICAL TRIAL REGISTRATIONS

ACTRN1260900028327, ACTRN12611001069943.

Finding the Gatekeeper to the Cardiac Catheterization Laboratory: Coronary CT Angiography or Stress Testing?

Functional capacity is a robust predictor of clinical outcomes, and stress testing is used in current practice paradigms to guide referral to invasive coronary angiography. However, invasive coronary angiography is driven by ongoing symptoms, as well as risk of adverse outcomes. The limitations of current functional testing-based paradigms might be avoided by using coronary computed tomographic angiography (CCTA) for exclusion of obstructive coronary artery disease. The growth of CCTA has been supported by comparative prognostic evidence with CCTA and functional testing, as well as radiation dose reduction. Use of CCTA for physiological evaluation of coronary lesion-specific ischemia may facilitate evaluation of moderate stenoses, designation of the culprit lesion, and prediction of benefit from revascularization. The potential of CCTA to serve as an effective gatekeeper to invasive coronary angiography will depend, in part, on the adoption of these new developments, as well as definition of the benefit of detecting high-risk plaque for guiding the management of selected patients.

Applying the diamond criteria could improve utilization of stress echocardiography for patients who present to the emergency department with low-risk chest pain

We identified all patients with age 21 years and older, without a history of obstructive coronary artery disease, who presented to the emergency department with chest pain, and were admitted for cardiac observation followed by stress echocardiography during a 1-year period. The positive predictive value of stress echocardiography and cardiovascular outcomes were compared based on patients' Diamond chest pain classification. In patients with typical chest pain, who accounted for 8.7% (44/503) of the total cohort, the positive predictive value of stress echocardiography was 75% compared with 0% for all other subgroups (P = 0.007). Six patients (14%) with typical chest pain went on to have coronary revascularization compared with 0% for all other subgroups (P < 0.001). No patient in any subgroup died or was readmitted with a myocardial infarction in 30 days. Applying the Diamond criteria could improve utilization of stress echocardiography for patients with low-risk chest pain in the emergency department.

Rationale and design of a randomized trial comparing initial stress echocardiography versus coronary CT angiography in low-to-intermediate risk emergency department patients with chest pain

BACKGROUND

Comparative effectiveness research (CER) has become a major focus of cardiovascular disease investigation to optimize diagnosis and treatment paradigms and decrease healthcare expenditures. Acute chest pain is a highly prevalent reason for evaluation in the Emergency Department (ED) that results in hospital admission for many patients and excess expense. Improvement in noninvasive diagnostic algorithms can potentially reduce unnecessary admissions.

OBJECTIVE

To compare the performance of treadmill stress echocardiography (SE) and coronary computed tomography angiography (CTA) in ED chest pain patients with low-to-intermediate risk of significant coronary artery disease.

DESIGN

This is a single-center, randomized controlled trial (RCT) comparing SE and CTA head-to-head as the initial noninvasive imaging modality. The primary outcome measured is the incidence of hospitalization. The study is powered to detect a reduction in admissions from 28% to 15% with a sample size of 400. Secondary outcomes include length of stay in the ED/hospital and estimated cost of care. Safety outcomes include subsequent visits to the ED and hospitalizations, as well as major adverse cardiovascular events at 30 days and 1 year. Patients who do not meet study criteria or do not consent for randomization are offered entry into an observational registry.

CONCLUSIONS

This RCT will add to our understanding of the roles of different imaging modalities in triaging patients with suspected angina. It will increase the CER evidence base comparing SE and CTA and provide insight into potential benefits and limitations of appropriate use of treadmill SE in the ED.

Role of imaging for acute chest pain syndromes

Acute chest pain suggestive of ischemic cardiac origin, with a normal or nondiagnostic electrocardiogram and negative initial cardiac markers for myocardial necrosis represent a significant diagnostic dilemma for clinicians. Multiple imaging modalities play a pivotal role in early diagnosis and safe discharge of these patients. In this review, we compare the current imaging modalities available for these patients including their diagnostic accuracy, feasibility, and cost effectiveness. Acute rest myocardial perfusion imaging significantly improves the clinical outcome in these patients and reduces the overall cost when incorporated into the decision making pathway. The choice of imaging modality recommended should be based on local institutional expertise and the overall clinical presentation. The imaging modality with high diagnostic accuracy and negative predictive value will provide for precise risk stratification which is important to clinical decision making, including patients who require admission to the hospital and those who can be safely discharged.

Stress echocardiography in the ED: diagnostic performance in high-risk subgroups

PURPOSE

To assess stress-echo (SE) diagnostic performance in patients presenting to the emergency department (ED) with spontaneous chest pain, especially in subgroups in which exercise ECG diagnostic performance has been questioned (women, elderly, history of coronary artery disease).

METHODS

Between June 2008 and May 2011, 474 patients with an episode of spontaneous chest pain, non-diagnostic electrocardiogram and negative cardiac necrosis markers underwent SE. Patients with inducible ischemia (Isch) were asked to undergo coronary angiography. Patients with negative SE were discharged and contacted by telephone at least 6 months after discharge, to ascertain the occurrence of new cardiac events.

MAIN FINDINGS

Exercise stress-echo (ESE) was employed in 270 patients and dobutamine (DSE) in 218 (including 14 with inconclusive ESE); a diagnosis of coronary artery disease (CAD) was confirmed or excluded in 434 (92%) patients. SE was negative for Isch in 318 patients (206 ESE and 112 DSE) and positive in 132. During follow-up, patients with negative SE had 4 cardiac events. SE showed: sensitivity 90%, specificity 92%, positive predictive value 78% and negative predictive value 97%. Sensitivity was comparable between patients aged < or ≥70 years (84 vs 94%) and between gender (89 vs 96%), but lower in patients with known CAD (88 vs 94%, P < .05); specificity was comparable regardless of age (94 vs 99%) and presence of CAD (97 vs 91%), but was lower among women (87 vs 96%, P < .05).

CONCLUSIONS

SE had a very good diagnostic performance in ED patients with suspected Isch, both overall and in selected high-risk groups.

Use of contrast echocardiography in intensive care and at the emergency room

Bedside echocardiography in emergency room (ER) or in intensive care unit (ICU) is an important tool for managing critically ill patients, to obtain a timely accurate diagnosis and to immediately stratify the risk to the patient’s life. It may also render invasive monitoring unnecessary. In these patients, contrast echocardiography may improve quality of imaging and also may provide additional information, especially regarding myocardial perfusion in those with suspected coronary artery disease. This article focuses on the principle of contrast echocardiography and the clinical information that can be obtained according to the most frequent presentations in ER and ICU.

Short- and long-term cardiac events in patients with chest pain with or without known existing coronary disease presenting normal electrocardiogram

AIM

The aim of this study is to evaluate incidence of adverse cardiac events in patients with chest pain with or without known existing coronary disease presenting normal electrocardiogram (ECG) and initial troponin.

METHODS

Prospective, nonrandomized study enrolled low-risk patients with normal ECG and troponin on admission who underwent observation and/or stress testing by unstandardized clinical judgment. Patients who experienced recurrent angina or positive ECGs or positive troponins during observation or patients with positive stress testing were admitted; otherwise, they were discharged.

END POINT

The end points are cardiac events at short- and long-term follow-up including cardiovascular death, myocardial infarction, unstable angina, and revascularization.

RESULTS

Of 5656 patients considered, 1732 with ischemic ECG were initially admitted and, therefore, excluded from the analysis; 2860 with pleuritic chest pain and normal ECG were discharged; 1064 with visceral chest pain and normal ECG were enrolled. Patients with known coronary disease (45%) were older and likely presented known vascular disease. Patients with known vascular disease, older age, female sex, diabetes mellitus, and lower chest pain score were likely managed with observation. In patients with known coronary disease as compared with patients without, overall cardiac events account for 35% vs 14%, respectively (P < .001), as follows: in-hospital, 23% vs 10%, (P < .001); 1 month, 4% vs 2% (P = .133); and 9.9 ± 4.9 months, 8% vs 2%, respectively (P < .001).

CONCLUSIONS

One-third of patients with chest pain with known coronary disease, negative ECG, and biomarkers were subsequently found to have adverse cardiac events. The value of this research for an emergency medicine audience could be extended to all clinicians and general practitioners beyond cardiologists.

Prognostic value of real time dobutamine stress myocardial contrast echocardiography in patients with chest pain syndrome

The aims of this study were (1) to evaluate the prognostic value of negative wall motion (WM) and myocardial perfusion during contrast-dobutamine stress echocardiography (DSE), (2) to determine whether WM-myocardial contrast echocardiography (MCE) had incremental prognostic value over just WM during DSE in patients with chest pain in the emergency room (ER), and (3) to compare the prognostic value of negative DSE-WM, and DSE-WM-MCE to nuclear-myocardial perfusion imaging (N-MPI) in a similar patient population over the same time period. We retrospectively studied 569 patients with real time contrast DSE, and 147 patients underwent N-MPI for evaluation of chest pain. Follow-up for cardiac events was obtained between 12 and 25 months. The cumulative cardiac event-free survival was 94.5% in negative DSE-WM, 97.1% in negative DSE-WM-MCE and 96.7% in negative N-MPI group. Cardiac event-free survival of the negative DSE-WM-MCE group was significantly higher than the DSE-WM group (log rank P < 0.01), and similar in the DSE-WM-MCE group compared to the N-MPI group. Combined WM and perfusion during DSE was the strongest independent predictor for cardiac events. The negative predictive power of DSE-WM-MCE is superior to that of just negative DSE-WM and is comparable to that of N-MPI. Myocardial perfusion and WM analysis during DSE provide independent information for predicting cardiac events in patients with chest pain syndrome in the ER.

GRACE and TIMI risk scores but not stress imaging predict long-term cardiovascular follow-up in patients with chest pain after a rule-out protocol

Objective

To determine the long-term prognostic value of stress imaging and clinical risk scoring for cardiovascular mortality in chest pain patients after ruling out acute coronary syndrome (ACS).

Methods

A standard rule-out protocol was performed in emergency room patients with a normal or non-diagnostic admission electrocardiogram (ECG) within 6 h of chest pain onset. ACS patients were identified by troponin T, recurrent angina and serial ECG. Dobutamine stress echocardiography (DSE) was performed after ACS was ruled out. Myocardial perfusion scintigraphy (MPS) was performed within 6 months in an outpatient setting according to the physician’s discretion.

Results

524 patients were included. GRACE and TIMI risk scores were 75 (57–96) and 1 (0–2) in the rule-out ACS group, and 89 (74–107) and 2 (1–3) in the ACS group, respectively (median, interquartile range). Follow-up (median 9.4 (8.9–10.0) years) was complete in 96%. 350 of 379 rule-out ACS patients had an interpretable DSE and 52 patients underwent an MPS. 21 of the rule-out ACS patients (6%) died of a cardiovascular cause compared with 24 (17%) ACS patients (p < 0.001). For rule-out ACS patients, C-statistics were 0.829 and 0.803 for the GRACE and TIMI scores. In these patients, DSE and MPS outcome did not predict long-term cardiovascular mortality. In multivariate analysis, known chronic heart failure, ACE inhibitor use, and GRACE score were independent predictors of cardiovascular mortality.

Conclusions

TIMI and GRACE score but not DSE and MPS are accurate predictors of long-term cardiovascular mortality, even in chest pain patients with a normal or non-diagnostic electrocardiogram undergoing a rule-out protocol.

Contrast stress-echocardiography predicts cardiac events in patients with suspected acute coronary syndrome but nondiagnostic electrocardiogram and normal 12-hour troponin

BACKGROUND

No large study has demonstrated that any stress test can risk-stratify future hard cardiac events (cardiac death or myocardial infarction) in patients with suspected acute coronary syndromes (ACS), nondiagnostic electrocardiographic (ECG) findings, and normal troponin levels. The aim of this study was to test the hypothesis that combined contrast wall motion and myocardial perfusion echocardiographic assessment (cMCE) during stress echocardiography can predict long-term hard cardiac events in patients with suspected ACS, nondiagnostic ECG findings, and normal troponin.

METHODS

A total of 545 patients referred for contrast stress echocardiography from the emergency department for suspected ACS but nondiagnostic ECG findings and normal troponin levels at 12 hours were followed up for cardiac events. Patients underwent dipyridamole-atropine echocardiography with adjunctive myocardial perfusion imaging using a commercially available ultrasound contrast medium (SonoVue).

RESULTS

During a median follow-up period of 12 months, 25 cardiac events (4.6%) occurred (no deaths, 12 nonfatal myocardial infarctions, 13 episodes of unstable angina). Abnormal findings on cMCE were the most significant predictor of both hard cardiac events (hazard ratio, 22.8; 95% confidence interval, 2.9-176.7) and the combined (cardiac death, myocardial infarction, or unstable angina requiring revascularization) end point (hazard ratio, 10.7; 95% confidence interval, 3.7-31.3). The inclusion of the cMCE variable significantly improved multivariate models, determining lower Akaike information criterion values and higher discrimination ability.

CONCLUSIONS

cMCE during contrast stress echocardiography provided independent information for predicting hard and combined cardiac events beyond that predicted by stress wall motion abnormalities in patients with suspected ACS, nondiagnostic ECG findings, and normal troponin levels.

N-terminal pro B-type natriuretic peptide identifies patients with chest pain at high long-term cardiovascular risk

BACKGROUND

Little is known about the long-term prognostic value of N-terminal pro B-type natriuretic peptide (NT-proBNP) and C-reactive protein (CRP) in low-risk patients with chest pain.

METHODS

Between June 1997 and January 2000, a standard rule-out protocol was performed in patients presenting to the emergency department within 6 hours of onset of chest pain with a normal or nondiagnostic electrocardiogram (ECG) on admission at the Academic Medical Center Amsterdam, VU University Medical Center Amsterdam and Medical Center Alkmaar, The Netherlands. Patients with acute coronary syndrome were identified by troponin T, recurrent angina, and serial ECGs. CRP and NT-proBNP on admission were measured using standardized methods.

RESULTS

A total of 524 patients were included (145 with acute coronary syndrome and 379 with rule-out acute coronary syndrome). Long-term follow-up was successfully carried out in 96% of the study population. Death occurred in 78 patients (15%), 43 (11%) in the rule-out acute coronary syndrome group and 35 (24%) in the acute coronary syndrome group (P<.001). In the rule-out acute coronary syndrome group, 21 patients (42%) died of a cardiovascular cause compared with 24 patients (69%) in the acute coronary syndrome group (P<.001). In multivariate Cox regression analysis, age more than 65 years, previous myocardial infarction, known chronic heart failure, a nondiagnostic ECG on admission, and elevated NT-proBNP levels (>87 pg/mL, as derived from the receiver operating characteristic curve) were independent predictors of long-term cardiovascular mortality in the rule-out acute coronary syndrome group. In the acute coronary syndrome group, these predictors were age more than 65 years, documented coronary artery disease, and elevated NT-proBNP levels. Elevated levels of CRP were an independent predictor for cardiovascular mortality in patients with rule-out acute coronary syndrome at 3-year follow-up only. In patients with rule-out acute coronary syndrome with normal CRP and NT-proBNP levels, the cardiovascular mortality incidence rate was 4.7 per 1000 person-years, compared with a death rate of 20 in patients with both biomarkers elevated, which was comparable to the 17.9 per 1000 person-years incidence rate in patients with acute coronary syndrome.

CONCLUSION

A positive biomarker panel discriminates patients with rule-out acute coronary syndrome chest pain with a normal or nondiagnostic ECG who have a high risk for long-term cardiovascular mortality.

Prognostic value of adenosine stress cardiovascular magnetic resonance and dobutamine stress echocardiography in patients with low-risk chest pain

Excluding obstructive coronary artery disease (CAD) as the etiology of acute chest pain in patients without diagnostic electrocardiographic changes or elevated serum cardiac biomarkers is challenging. Stress testing is a valuable risk-stratifying technique reserved for the subset of these patients with low-risk chest pain who have an intermediate clinical probability of obstructive CAD. Given the risks of radiation inherent to nuclear and computed tomography imaging, both adenosine stress cardiovascular magnetic resonance (AS-CMR) imaging and dobutamine stress echocardiography (DSE) are attractive alternative stress modalities. An essential characteristic of stress modalities is their negative prognostic value; as one must exclude clinically-relevant CAD such that patients can be discharged safely. Therefore, the aim of this study was to validate a favorable negative prognostic value for both AS-CMR and DSE in patients presenting with low-risk acute chest pain. This retrospective study included 255 patients with low-risk acute chest pain and no prior history of CAD presenting to the emergency department at our institution, with 89 patients evaluated by AS-CMR and 166 by DSE. Median follow-up was 292 days, and consisted of medical record review. The primary end-point was the composite of cardiac death, nonfatal acute myocardial infarction, obstructive CAD on invasive coronary angiography (ICA) or recurrent chest pain requiring hospital admission. Test characteristics such as sensitivity and specificity could not be evaluated as patients were not routinely evaluated with ICA. All patients completed the stress protocol without adverse events during testing. 82/89 patients (92.1%) and 164/166 patients (98.8%) had negative AS-CMR and DSE studies, respectively. Both AS-CMR and DSE had excellent negative prognostic values for the primary endpoint, 100 and 99%, respectively. Both AS-CMR and DSE are effective stress modalities for excluding clinically significant coronary artery disease in patients presenting acute low-risk chest pain. Patients without findings to suggest ischemia have an excellent intermediate-term prognosis.

Usefulness of contrast stress-echocardiography or exercise-electrocardiography to predict long-term acute coronary syndromes in patients presenting with chest pain without electrocardiographic abnormalities or 12-hour troponin elevation

The evaluation of patients presenting to the hospital with a recent episode of chest pain suggestive of myocardial ischemia, nondiagnostic electrocardiographic findings, and normal 12-hour cardiac troponin levels remains a challenge for the clinician. We selected 1,081 consecutive patients who presented to the emergency department during 2008 for a chest pain complaint of suspected cardiac origin without significant electrocardiographic abnormalities or troponin elevation. These patients underwent either contrast-enhanced stress-echocardiography with myocardial perfusion imaging or exercise-electrocardiography within 5 days of the index admission. We analyzed their 1-year cardiac outcome (i.e., unstable angina, myocardial infarction, or cardiac death). A post test likelihood of cardiac events was determined on the basis of the results of the provocative testing. Significantly better event-free survival (log-rank p <0.0001) was found for both hard (cardiac death and nonfatal myocardial infarction) and combined (acute coronary syndrome) end points in patients with normal contrast-enhanced stress-echocardiographic findings. However, this was not the case for patients in the exercise-electrocardiographic group, for whom event-free survival was not significantly different among the 3 possible result categories (normal, indeterminate, and abnormal test findings; log-rank p = NS). In conclusion, inducible ischemia detected by contrast-enhanced stress-echocardiography predicted the 1-year incidence of acute coronary syndrome (11.3% for positive vs 0.8% for negative results). However, this was not the case for exercise-electrocardiography, with a 2.7%, 2.3%, and 2.9% 1-year incidence of acute coronary syndromes for positive, negative, and indeterminate results, respectively.

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.

Predictive value of normal dobutamine stress echocardiogram in patients with low-risk acute chest pain

Dobutamine stress echocardiography (DSE) has been proposed as a tool for risk stratification of patients with acute chest pain (ACP). In this single-center study, we evaluated the negative predictive value of DSE in 178 patients who presented with low-risk ACP (normal or inconclusive electrocardiogram and negative markers of myocardial damage) and were discharged following a maximal DSE that did not reveal ischemia. During the follow-up (median 321 days), 2 of the 178 patients were admitted with an acute coronary syndrome and were diagnosed with obstructive coronary artery disease at angiography. In the time frame of the study, the negative predictive value of a normal and maximal DSE for an adverse cardiac event was 98.9% (95% CI: 96.0-99.8%). Thus, a normal DSE has a high negative predictive value and comprises a safe and effective tool for early risk stratification of patients who present with acute chest pain of low risk.

Effect on quality of life of different accelerated diagnostic protocols for management of patients presenting to the emergency department with acute chest pain

This study assessed the effects on quality of life (QoL) of dobutamine-atropine stress echocardiography (DASE) and electrocardiogram exercise testing (EET) accelerated diagnostic protocols for early stratification of low-risk patients with acute chest pain (ACP). A total of 290 patients with ACP, a nondiagnostic electrocardiogram, and negative biomarkers were randomly assigned to an accelerated diagnostic protocol (DASE, n = 110, or EET, n = 89) or usual care (n = 91) and followed up for 2 months. QoL was assessed at discharge and 2-month follow-up using the Nottingham Health Profile questionnaire. Baseline and 2-month follow-up answers to the Nottingham Health Profile questionnaire were available for 207 patients (71%; 55 in the usual-care, 77 in the DASE, and 75 in the ETT arm). At predischarge, patients in the usual-care arm reported higher impairment in the physical mobility and pain dimensions compared with the DASE and EET arms (p = 0.019 and p = 0.023, respectively). At 2-month follow-up, QoL improved in all groups; however, patients in the usual-care arm had significantly worse scores than patients managed using accelerated diagnostic protocols in the physical mobility, pain, social isolation, emotional reactions, and energy level dimensions (p = 0.014, p = 0.002, p = 0.04, p = 0.01, and p = 0.003, respectively). In conclusion, low-risk patients with ACP had non-negligible impairment of QoL in the acute phase. Emergency department ADPs with early DASE and EET reduced QoL impairment at both baseline and 2-month follow-up.