Care of patients with a low probability of acute myocardial infarction. Cost effectiveness of alternatives to coronary-care-unit admission

Cardiac CT in the Emergency Department: Contrasting Evidence from Registries and Randomized Controlled Trials

PURPOSE OF REVIEW

To compare outcomes between registries and randomized controlled trials of coronary computed tomographic angiography (CCTA)-based versus standard of care approaches to the initial evaluation of patients with acute chest pain.

RECENT FINDINGS

Randomized trials have demonstrated CCTA to be a safe and efficient tool for triage of low- to intermediate-risk patients presenting to the emergency department with chest pain. Recent studies demonstrate heterogeneous result using different standard of care approaches for evaluation of hard endpoints in comparison with standard evaluation. Also, there has been continued concern for increase in subsequent testing after coronary CTA. Although CCTA improves detection of coronary artery disease, it is uncertain if it will bring improvement of long-term health outcomes at this point of time. Careful analysis of the previous results and further investigation will be required to validate evaluation of hard endpoints.

A Novel Neuroscience Intermediate-Level Care Unit Model: Retrospective Analysis of Impact on Patient Flow and Safety

BACKGROUND AND PURPOSE

Neurointensive care units have been shown to improve patient outcomes across a variety of neurological and neurosurgical conditions. However, the efficacy of less resource-intensive intermediate-level care units to deliver similar care has not been well studied. The purpose of this study is to evaluate the impact of neurocritical specialist comanagement on patient flow and safety in a neuroscience intermediate-level care unit.

METHODS

Our intervention consisted of the addition of a physician with critical care experience as well as training in neurology, anesthesiology, or intensive care to a neuroscience intermediate-level care unit to comanage patients alongside neurology and neurosurgery staff during weekday daytime hours. A retrospective analysis was performed on prospectively collected data pertaining to all patients admitted to the unit over a 3-year period, 1 year before our intervention and 2 years after. Patient statistics including wait times to admission, length of stay (LOS), and mortality were reviewed.

RESULTS

Following the intervention, there were significant reductions in wait times to unit admission from both the emergency department and postanesthetic care unit, as well as reductions in the average LOS. No significant safety concerns were identified.

CONCLUSION

This study has demonstrated that the optimization of a neuroscience intermediate-level care unit involving comanagement of patients by a neurocritical specialist can reduce wait times to admission and lengths of stay, with preserved safety outcomes.

Systematic Review of Economic Evaluations of Units Dedicated to Acute Coronary Syndromes

BACKGROUND

Dedicated units for the care of acute coronary syndrome (ACS) have been submitted to economic evaluations; however, the results have not been systematically presented.

OBJECTIVE

To identify and summarize economic outcomes of studies on hospital units dedicated to the initial care of patients with suspected or confirmed ACS.

METHODS

A systematic review of literature to identify economic evaluations of chest pain unit (CPU), coronary care unit (CCU), or equivalent units was done. Two search strategies were used: the first one to identify economic evaluations irrespective of study design, and the second one to identify randomized clinical trials that reported economic outcomes. The following databases were searched: MEDLINE, EMBASE, CENTRAL, and National Health Service (NHS)Economic Evaluation Database. Data extraction was performed by two independent reviewers. Costs were inflated to 2012 values.

RESULTS

Search strategies retrieved five partial economic evaluations based on observational studies, six randomized clinical trials that reported economic outcomes, and five model-based economic evaluations. Overall, cost estimates based on observational studies and randomized clinical trials reported statistically significant cost savings of more than 50% with the adoption of CPU care instead of routine hospitalization or CCU care for suspected low-to-intermediate risk patients with ACS (median per-patient cost US $1,969.89; range US $1,002.12-13,799.15). Model-based economic evaluations reported incremental cost-effectiveness ratios below US $ 50,000/quality-adjusted life-year for all comparisons between intermediate care unit, CPU, or CCU with routine hospital admissions. This finding was sensible to myocardial infarction probability.

CONCLUSIONS

Published economic evaluations indicate that more intensive care is likely to be cost-effective in comparison to routine hospital admission for patients with suspected ACS.

Cardiac CT angiography for evaluation of acute chest pain

Chest pain is the second most common emergency department (ED) presentation in the United States. Cardiac computed tomography angiography (CCTA) now plays an important role in the evaluation of patients with suspected acute coronary syndrome in the ED setting. In this article, we review the available techniques focused on the use of CCTA to evaluate patients fosr coronary atherosclerosis for timely triage of acute chest pain.

A new chest pain strategy in Thunder Bay

Thunder Bay Regional Hospital (TBRH) developed a chest pain strategy (CPS) to support its emergency physicians in making the difficult clinical decisions required to properly evaluate and manage ED “chest pain” patients. This strategy was developed to ensure excellent patient care in a setting of diminished inpatient bed availability and increasing ED congestion. It focuses on rapid risk stratification, using history, electrocardiogram, physical examination and 3 new point-of-care cardiac markers: myoglobin, CK-MB mass, and cardiac troponin I.

Following the introduction of the CPS in 1997, TBRH realized significant ($500 000/yr) institutional resource savings through a 60% decrease in the admission rate of non-myocardial infarction, non-unstable angina chest pain patients, a 30% decrease in ED chest pain evaluation time, and improved ED availability of monitored stretchers. The CPS has allowed TBRH to simultaneously decrease costs and improve patient care.

The impact of the organization of high-dependency care on acute hospital mortality and patient flow for critically ill patients

RATIONALE

Little is known about the utility of provision of high-dependency care (HDC) that is in a geographically separate location from a primary intensive care unit (ICU).

OBJECTIVES

To determine whether the availability of HDC in a geographically separate unit affects patient flow or mortality for critically ill patients.

METHODS

Admissions to ICUs in the United Kingdom, from 2009 to 2011, who received Level 3 intensive care in the first 24 hours after admission and subsequently Level 2 HDC. We compared differences in patient flow and outcomes for patients treated in hospitals providing some HDC in a geographically separate unit (dual HDC) with patients treated in hospitals providing all HDC in the same unit as intensive care (integrated HDC) using multilevel mixed effects models.

MEASUREMENTS AND MAIN RESULTS

In 192 adult general ICUs, 21.4% provided dual HDC. Acute hospital mortality was no different for patients cared for in ICUs with dual HDC versus those with integrated HDC (adjusted odds ratio, 0.94 [0.86-1.03]; P = 0.16). Dual HDC was associated with a decreased likelihood of a delayed discharge from the primary unit. However, total duration of critical care and the likelihood of discharge from the primary unit at night were increased with dual HDC.

CONCLUSIONS

Availability of HDC in a geographically separate unit does not impact acute hospital mortality. The potential benefit of decreasing delays in discharge should be weighed against the increased total duration of critical care and greater likelihood of a transfer out of the primary unit at night.

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.

Stress myocardial perfusion imaging for the evaluation and triage of chest pain in the emergency department: a randomized controlled trial

BACKGROUND

Patients with acute coronary syndrome (ACS) often present atypically. In a randomized controlled trial, we studied whether adding stress myocardial perfusion imaging (SMPI) to an evaluation strategy for emergency department (ED) patients presenting with chest pain more effectively identifies patients with ACS.

METHODS

Participants were randomized to standard ED chest pain protocol (clinical assessment) or standard protocol supplemented with SMPI results. During 6 hours of electrocardiogram (ECG) monitoring and serial cardiac markers (creatine kinase-MB isoenzyme, troponin), participants developing ST segment changes or elevated cardiac markers were admitted. Those with a negative observation period underwent SMPI (N = 1,004) or clinical assessment (N = 504) based on randomization, and admitted if their SMPI scan was abnormal or senior clinicians found a high or intermediate risk for ACS.

RESULTS

SMPI participants had a significantly lower admission rate than clinical assessment participants (10.16% vs 18.45%), with no significant between-group differences in risk of cardiac events (CEs) after 30 days (0.40% vs 0.79%) or 1 year (0.70% vs 0.99%).

CONCLUSIONS

When added to a standard triage strategy incorporating clinical evaluation, serial ECGs, and cardiac markers, SMPI improved clinical decision making for chest pain patients, significantly reducing the need for hospitalization without an increase in adverse CE rates at 30 days or 1 year.

Emergency physician estimates of the probability of acute coronary syndrome in a cohort of patients enrolled in a study of coronary computed tomographic angiography

INTRODUCTION

Little information exists regarding how accurately emergency physicians (EPs) predict the probability of acute coronary syndrome (ACS). Our objective was to determine if EPs can accurately predict ACS in a prospectively identified cohort of emergency department (ED) patients who met enrolment criteria for a study of coronary computed tomographic angiography (CCTA) and were admitted for a "rule out ACS" protocol.

METHODS

A prospective observational pilot study in an academic medical centre was carried out. EPs caring for patients with chest pain provided whole-number estimates of the probability of ACS after clinical review. This substudy was part of the now published Rule Out Myocardial Infarction/Ischemia Using Computer Assisted Tomography (ROMICAT) study, a study of CCTA and admission of patients for a rule out ACS protocol after a nondiagnostic evaluation. Predictions were grouped into probability groups based on the validated Goldman criteria. ACS was determined by an adjudication committee using American Heart Association/American College of Cardiology/European Society of Cardiology guidelines.

RESULTS

A total of 334 predictions were obtained for a study population with a mean age of 54 (SD 12) years, 63% of whom were male. There were 35 ACS events. EPs predicted ACS better than by chance, and increasingly higher estimates were associated with a higher incidence of ACS (p = 0.0004). The percentage of patients with ACS was 0%, 6%, 7%, and 17%, respectively, for very low, low, intermediate, and high probability groups. EPs' estimates had a sensitivity of 63% using a > 20% probability of ACS to define a positive test. Lowering this threshold to > 7% to define a test as positive increased the sensitivity of physician estimates to 89% but lowered specificity from 65% to 24%.

CONCLUSION

Our data suggest that for a selected ED cohort meeting eligibility criteria for a study of CCTA, EPs predict ACS better than by chance, with an increasing proportion of patients proving to have ACS with increasing probability estimates. Lowering the estimate threshold does not result in an overall sensitivity level that is sufficient to send patients home from the ED and is associated with a poor specificity.

Cost burden of non-specific chest pain admissions

BACKGROUND

Non-cardiac aetiologies are common among patients presenting with chest pain.

AIM

To determine the cost of non-specific chest pain admissions to a tertiary referral, teaching hospital.

METHODS

Thrombolysis in myocardial infarction risk (TIMI) risk score, lengths of stay (LOS), investigations and diagnoses were recorded for patients admitted with chest pain. Non-specific chest pain was defined as chest pain where cardiac, pulmonary and gastroesophageal aetiologies were excluded. Costs of admissions were calculated.

RESULTS

Of 80 patients, 34 (4%) and 22 (28%) were diagnosed with non-specific chest pain and acute coronary syndrome, respectively. Non-specific chest pain admissions had a mean age of 54 (11; 35-74) years, LOS of 3.8 (2.6; 1-11) days and TIMI risk score of 1.4 (1.5; 0-5). Acute coronary syndrome admissions had a mean age of 67 (14; 43-94) years, LOS of 7.7 (4.3; 2-16) days and TIMI risk score of 3.1 (1.2; 0-5). The mean cost per non-specific chest pain admission was €3,729 (2,378; 1,034-10,468), or 48% of the mean cost per acute coronary syndrome admission of €7,667 (4,279; 1,963-16,071). Bed day costs account for >90% of overall costs. Only 7% of patients were weekend discharges. The mean interval to exercise stress test was 2.7(1.5; 1-7) days.

CONCLUSIONS

The mean costs of admission and LOS for patients with non-specific chest pain are significant. Extrapolating findings, annual national cost is estimated at approximately €71 million for this cohort, with 73,000 bed days consumed nationally. Delays from admission to tests and low percentage of weekend discharges prolong LOS.

[Radiologists in the emergency department: when and how to use multislice CT]

Chest pain is a challenging clinical problem in the emergency department. Despite advances in clinical diagnosis, many patients with atypical chest pain are needlessly hospitalized and others are mistakenly discharged. Faced with the specific clinical situation in which a patient has chest pain, an initially normal or inconclusive electrocardiogram, and normal cardiac biomarkers, multislice CT has proven useful for ruling out the conditions that involve the greatest morbidity and mortality and for establishing the cause of pain. This article reviews the current usefulness of multislice CT in the diagnostic workup of patients presenting at the emergency department with chest pain. We review the technique, define the most appropriate population, describe the acquisition protocols, and discuss the advantages and disadvantages of each study protocol.

Evaluation of acute chest pain in the emergency department: "triple rule-out" computed tomography angiography

Triage of patients with acute, potentially life-threatening chest pain is one of the most important issues currently facing physicians in the emergency department. Appropriate evaluation of these patients begins with a skilled assessment of the individual patient's presenting symptoms and a careful review of his or her history and physical examination, often followed by serial recording of electrocardiograms and measurement of serum biochemical markers such as troponin and d-dimer. Stress testing, often accompanied by rest and stress myocardial perfusion imaging or echocardiography, and other diagnostic testing such as radionuclide lung scanning and invasive angiography may be required. A rapid, accurate, and cost-effective approach for the evaluation of emergency department patients with chest pain is needed. Development of newer generations of multidetector computed tomographic (MDCT) scanners, which are capable not only of performing high-quality noninvasive coronary angiography, but also concurrent aortic and pulmonary angiography, has led to increased use of MDCT for the so-called "triple rule out." MDCT is used for the detection of 3 of the most common life-threatening causes of chest pain-coronary artery disease, acute aortic syndrome, and pulmonary emboli. While triple rule-out protocol can be very useful and potentially cost effective when used appropriately, concern has risen regarding the overuse of this technology, which could expose patients to unnecessary radiation and iodinated contrast. The triple rule-out protocol is most appropriate for patients who present with acute chest pain, but are judged to have low to intermediate increased risk for acute coronary syndrome, and whose chest pain symptoms might also be attributed to acute pathologic conditions of the aorta or pulmonary arteries. MDCT should not be used as a routine screening procedure. Continued technical improvements in acquisition speed and spatial resolution of computed tomography images, and development of more efficient image reconstruction algorithms which reduce patient exposure to radiation and contrast, may result in increased popularity of MDCT for "triple rule-out."

Imaging of non-cardiac, non-traumatic causes of acute chest pain

Non-traumatic chest pain is a common symptom in patients who present in the emergency department. From a clinical point of view, it is important to differentiate cardiac chest pain from non-cardiac chest pain (NCCP). Among the plethora of potential causes of NCCP, life-threatening diseases, such as aortic dissection, pulmonary embolism, tension pneumothorax, and esophageal rupture, must be differentiated from non-life threatening causes. The majority of NCCP, however, is reported to be benign in nature. The presentation of pain plays an important role in narrowing the differential diagnosis and initiating further diagnostic management and treatment. As the benign causes tend to recur, and may lead to patient anxiety and great costs, a meticulous evaluation of the patient is necessary to diagnose the underlying disorder or disease.

Evaluation of the patient with acute chest pain

The past decade has brought rapid advances in CT technology, which allows increasingly precise application to the study of coronary arteries and acute chest pain. The literature has expanded to lend quantifiable justification to the intuitive appeal of a rapid, reproducible, 3D study of the heart and vasculature. More complete analysis of efficacy and costs on broader populations will further refine our understanding of how best to implement what may become the new gold standard. Meanwhile, evolving technology promises to further challenge radiologists and clinicians to optimize approach and diagnosis to acute chest pain.

Comparison of myocardial contrast echocardiography versus rest sestamibi myocardial perfusion imaging in the early diagnosis of acute coronary syndrome

BACKGROUND

It remains unclear whether myocardial contrast echocardiography (MCE) is as accurate as myocardial perfusion imaging with technetium-99m sestamibi (MPI) for the diagnosis of acute coronary syndrome (ACS). We sought to directly compare the diagnostic accuracy of MCE with resting MPI in a head-to-head fashion.

METHODS

We prospectively enrolled 98 consecutive patients (mean age; 59+/-9 years, 68 males) who presented to the emergency department with chest pain suggestive of acute myocardial ischemia. Early MCE was performed by using continuous infusion of perfluorocarbon-exposed sonicated dextrose albumin (PESDA) during intermittent power Doppler harmonic imaging. Myocardial perfusion defects observed in at least one coronary territory were considered positive. Sestamibi was injected immediately after MCE and MPI was obtained within 6 hours of tracer injection.

RESULTS

ACS was confirmed in 67 patients. There were 32 patients with acute myocardial infarction (AMI) and 35 patients with unstable angina requiring urgent revascularization. The sensitivities of MCE and MPI for the diagnosis of ACS were 72% and 61%, respectively, which were significantly higher than those of ST segment change (24%, p<0.001 vs. MCE and vs. MPI) and troponin I (27%, p<0.001 vs. MCE and vs. MPI), with similar specificities of 90% to 100%. On a receiveroperating characteristics curve demonstrating diagnostic accuracy for ACS, the area under the curve of MCE was significantly larger than that of MPI (0.86 vs. 0.77, respectively; p=0.019).

CONCLUSION

MCE and MPI overcome the low sensitivity of routine triage tests for detecting ACS, and MCE is more accurate than MPI for the diagnosis of ACS in the emergency department.

Coronary computed tomographic angiography (CCTA) in community hospitals: "current and emerging role"

Coronary computed tomographic angiography (CCTA) is a rapidly evolving test for diagnosis of coronary artery disease. Although invasive coronary angiography is the gold standard for coronary artery disease (CAD), CCTA is an excellent noninvasive tool for evaluation of chest pain. There is ample evidence to support the cost-effective use of CCTA in the early triage process of patients presenting with chest pain in the emergency room. CCTA plays a critical role in the diagnosis of chest pain etiology as one of potentially fatal conditions, aortic dissection, pulmonary embolism, and myocardial infarction. This 'triple rule out' protocol is becoming an increasingly practicable and popular diagnostic tool in ERs across the country. In addition to a quick triage of chest pain patients, it may improve quality of care, decrease cost, and prevent medico-legal risk for missing potentially lethal conditions presenting as chest pain. CCTA is also helpful in the detection of subclinical and vulnerable coronary plaques. The major limitations for wide spread acceptance of this test include radiation exposure, motion artifacts, and its suboptimal imaging with increased body mass index.

["Surgical intermediate care unit" outcomes, facts and experiences after 5 years]

The increasing economic pressure has resulted in strategies to use efficient treatment forms. The aim of our study was to evaluate to which extent the intermediate care unit (IMC-unit) relieves the intensive care unit and the wards. We analyzed: patient population, age, gender, admission criteria and the rate of patients with intensive nursing procedures between January 1, 2005 and December 31, 2007. The level of care was calculated according to the standard patient categories. The mean age amounted to 58.9 years. Intensive care patients made up 43.6% and patients from the emergency ward 36.6% of the total IMC-allocation. After IMC care 54.3% of all IMC-patients could be taken over by wards. The confused patients amounted to 27.5% and isolated patients 4.3%. The average care intensity amounted to 4.5 hours per patient daily and the mean length of stay in hospital was 9 days. Particularly the relief of nursing intensity and the possibility of primary treatment of severely injured persons reflect the requirements of IMC.

Can computed tomography improve outcomes in acute coronary syndrome?

Each year, six million patients in the USA visit the emergency department for acute chest pain. Many patients are hospitalized because immediate discharge of those suspected of acute coronary syndrome could be disastrous. This review looks at whether patient outcomes could be improved by coronary computed tomography angiography.

Are the American College of Cardiology/Emergency Cardiac Care (ACC/ECC) guidelines useful in triaging patients to telemetry units?

PURPOSE

To determine if the ACC/ECC guidelines (1991) properly stratify patients according to risk of arrhythmia, defined as a single event on cardiac monitoring, and benefit, defined as a subsequent management change from a recorded telemetry event.

SUBJECTS AND METHODS

In 2003, a prospective study of 217 consecutive patients admitted to a 24-bed telemetry unit was conducted for 25 days at a major academic hospital. Patients were categorized per ACC/ECC guidelines as appropriate (class I & II) or inappropriate (class III) based on a non-cardiologist admission diagnosis. A cardiologist-led group then reclassified patients at the time of admission using a brief interview. Continuous telemetry-recorded arrhythmias and resultant management changes were reviewed and recorded daily. Subgroup analysis of patients admitted with a chief complaint of chest pain was also performed. In 2004, after this trial was performed, the American Heart Association released a scientific statement updating practice standards for ECG monitor; however, this paper is based upon the original 1991 ACC/ECC guidelines.

RESULTS

Reclassification significantly decreased the percentage of all class I & II patients from 91% to 71% (P<0.001) and the percentage of class I & II patients with chest pain from 100% to 58% (P<0.001) without increasing the percentage of arrhythmias occurring in class III patients. Class II patients had a statistically significant higher percentage of arrhythmias than class I and III patients before and after reclassification (P<0.001 and P<0.001, respectively). Management changes occurring as a direct result of telemetry events were higher in class II than class I or III patients before and after reclassification (P = 0.01 and P = 0.03). Life-threatening arrhythmias (sustained ventricular tachycardia or ventricular fibrillation) occurred in 1% of the 216 patients enrolled in this study.

CONCLUSIONS

(1) Cardiology input using ACC/ECC guidelines and a brief interview at admission safely reduced total admissions primarily by identifying low risk chest pain admissions inappropriate for inpatient telemetry monitoring. (2) Life threatening arrhythmias occurring in patients admitted to telemetry are rare.

Significance of cardiac computed tomography incidental findings in acute chest pain

BACKGROUND

Coronary computed tomography angiography might improve the management of patients presenting to the emergency department with acute chest pain; however, noncoronary incidental findings are frequently detected. The prevalence and clinical significance of these findings have not been well described.

METHODS

Consecutive patients presenting to the emergency department with acute chest pain and inconclusive initial evaluation between May 2005 and May 2007 underwent 64-slice coronary computed tomography angiography before hospital admission with noncoronary incidental findings immediately reported. An expert panel adjudicated which incidental findings changed in-hospital patient management, and projections for additional testing were based on standard medical practice.

RESULTS

Among 395 patients (37.0% were female, mean age 53 +/- 12 years), incidental findings were detected in 44.8% (n = 177): noncalcified pulmonary nodules (n = 94, 23.8%), simple liver cysts (n = 26, 6.6%), calcified pulmonary nodules (n = 16, 4.1%), and contrast-enhancing liver lesions (n = 9, 2.3%). In-hospital management was changed because of incidental finding reporting in 5 patients (1.3%), and a potential alternative diagnosis was offered in another 16 patients (4.1%). Subsequent diagnostic imaging tests were recommended in 81 patients (20.5%), including 74 chest computed tomography scans. After 6 months, biopsy was performed in 3 patients, revealing cancer in 2 (0.5%) who underwent successful tumor resection.

CONCLUSION

Clinically important findings are detected in up to 5% of patients with a lead symptom of acute chest pain and low to intermediate likelihood of acute coronary syndrome, but only few directly change patient management; 21% are recommended for further imaging tests, resulting in invasive procedures and detection of cancer in few patients.

Coronary computed tomographic angiography for rapid discharge of low-risk patients with potential acute coronary syndromes

STUDY OBJECTIVE

Coronary computed tomographic (CT) angiography has excellent performance characteristics relative to coronary angiography and exercise or pharmacologic stress testing. We hypothesize that coronary CT angiography can identify a cohort of emergency department (ED) patients with a potential acute coronary syndrome who can be safely discharged with a less than 1% risk of 30-day cardiovascular death or nonfatal myocardial infarction.

METHODS

We conducted a prospective cohort study at an urban university hospital ED that enrolled consecutive patients with potential acute coronary syndromes and a low TIMI risk score who presented to the ED with symptoms suggestive of a potential acute coronary syndrome and received a coronary CT angiography. Our intervention was either immediate coronary CT angiography in the ED or after a 9- to 12-hour observation period that included cardiac marker determinations, depending on time of day. The main clinical outcome was 30-day cardiovascular death or nonfatal myocardial infarction.

RESULTS

Five hundred sixty-eight patients with potential acute coronary syndrome were evaluated: 285 of these received coronary CT angiography immediately in the ED and 283 received coronary CT angiography after a brief observation period. Four hundred seventy-six (84%) were discharged home after coronary CT angiography. During the 30-day follow-up period, no patients died of a cardiovascular event (0%; 95% confidence interval [CI] 0% to 0.8%) or sustained a nonfatal myocardial infarction (0%; 95% CI 0 to 0.8%).

CONCLUSION

ED patients with symptoms concerning for a potential acute coronary syndrome with a low TIMI risk score and a nonischemic initial ECG result can be safely discharged home after a negative coronary CT angiography test result.

Review: Hypertension, a health economics perspective

The economic aspects of hypertension are critical to modern medicine. The medical, economic, and human costs of untreated and inadequately controlled hypertension are enormous. Hypertension is distributed unequally and with iniquity in different countries and regions of the world. Treatment of hypertension requires an investment over many years to prolong disease-free quality years of life. The high prevalence and high cost of the disease impacts on the microeconomics and macroeconomics of countries and regions. The criteria used for inclusion in clinical guidelines for hypertension impact on the cost and cost/utility of diagnosis or treatment.

The role of cardiovascular imaging techniques in the assessment of patients with acute chest pain

Chest pain is the most common presenting symptom of coronary artery disease. The assessment and appropriate management of patients with acute chest pain and non-diagnostic electrocardiograms (ECGs) remain a continuing clinical problem, with major logistic and financial implications for health-care providers. Cardiovascular imaging is at the forefront of health care, experiencing rapid changes over the recent years, particularly with the use of advanced medical technologies. Imaging techniques like acute rest myocardial perfusion imaging (MPI), echocardiography, electron beam computed tomography (CT), cardiac magnetic resonance imaging (MRI) and multi-detector CT (MDCT) have been used recently in the evaluation and triage of patients with chest pain in addition to the conventional investigations such as ECGs and cardiac biomarkers in the chest pain units. The annual potential cost savings, by incorporating the routine use of acute rest MPI in patients with low-to-moderate risk and non-diagnostic ECGs are substantial. The high negative predictive value of a normal resting MPI in patients with chest pain for myocardial infarction and future cardiac events is well established. Echocardiography is also considered to be useful but the technique is operator dependent and at present there is insufficient data to support its use. Cardiac MRI is expensive and time consuming and there is insufficient diagnostic and prognostic data to make it suitable for chest pain patients at present. There has been increasing interest in MDCT recently, especially with the advent of 64-slice CT but the sensitivity and specificity in chest pain patients are no better than MPI so far.

[Care grading in Intensive Medicine: Intermediate Care Units]

Intermediate Care Units are created for patients who predictably have low risk of requiring therapeutic life support measures but who require more monitoring and nursing cares than those received in the conventional hospitalization wards. Previous studies have demonstrated that Intermediate Care Units may promote hospital care grading, allowing for better classification in critical patients, improving efficacy and efficiency of the ICUs and thus decreasing costs and above all mortality in the conventional hospitalization wards. This document attempts to group the currently existing knowledge that served as a base for the consensus meeting on the application of them in the establishment of future ICUs in our hospital setting.

Contrast ultrasound in the assessment of patients presenting with suspected cardiac ischemia

Echocardiography is a portable technology that can be used to assess myocardial, pericardial, and valvular structure and function. Doppler echocardiography provides the ability to evaluate blood flow in large vessels and within cardiac chambers. Recently, the advent of microbubble contrast agents, which can opacify the systemic circulation, has improved the ability of echocardiography to evaluate left-ventricular function by improving delineation of the left-ventricular endocardial border. Furthermore, these microbubbles can be used to assess myocardial perfusion and quantify myocardial blood flow. Myocardial contrast echocardiography has been studied in multiple clinical situations, including the acute evaluation of patients presenting with suspected cardiac ischemia. Ongoing research is focused on the development of microbubbles that are capable of detecting molecular and cellular events within the circulation, which may allow distinction of acute vs. remote ischemic insults to the myocardium. This multifaceted technology promises to be of increasing clinical utility--not only for the heart, but for any organ accessible to ultrasound.

Relationship between a clear-cut alternative noncardiac diagnosis and 30-day outcome in emergency department patients with chest pain

BACKGROUND

Accurate identification of patients with acute coronary syndromes (ACSs) in the emergency department (ED) remains problematic. Studies have not been able to identify a cohort of patients that are safe for immediate ED discharge; however, prior studies have not examined the utility of a clear-cut alternative noncardiac diagnosis.

OBJECTIVES

To compare the 30-day event rate in ED chest pain patients who were diagnosed with a clear-cut alternative noncardiac diagnosis with the 30-day event rate in the cohort of patients in whom a definitive diagnosis could not be made in the ED.

METHODS

This was a prospective cohort study of consecutive ED patients with potential ACS. Data included demographics, medical and cardiac history, laboratory and electrocardiogram results, and whether or not the treating physician ascribed the condition to a clear-cut alternative noncardiac diagnosis. The main outcome was death, acute myocardial infarction (AMI), or revascularization within 30 days, as determined by phone follow-up or medical record review.

RESULTS

The investigators enrolled 1,995 patients in the ED who had potential ACSs. Overall, 77 had a final hospital diagnosis of AMI (4%). Within 30 days, 73 patients received revascularization (4%), and 26 died (1%). There were 599 (30%) patients given a clear-cut alternative noncardiac diagnosis. Comparing the patients with a clear-cut alternative noncardiac diagnosis with those without an obvious noncardiac diagnosis, the presence of a clear-cut alternative noncardiac diagnosis was associated with a reduced risk of an in-hospital triple-composite endpoint (death, MI, and revascularization), with a risk ratio of 0.32 (95% confidence interval [CI] = 0.19 to 0.55) and 30-day triple-composite endpoint with a risk ratio of 0.45 (95% CI = 0.29 to 0.69); however, patients with a clear-cut alternative noncardiac diagnosis still had a 4% event rate at 30 days (95% CI = 2.4% to 5.6%).

CONCLUSIONS

In the ED chest pain patient, the presence of a clear-cut alternative noncardiac diagnosis reduces the likelihood of a composite outcome of death and cardiovascular events within 30 days. However, it does not reduce the event rate to an acceptable level to allow ED discharge of these patients.

Continuous 12-lead ST-segment monitoring improves identification of low-risk patients with chest pain and a worse in-hospital outcome

BACKGROUND

Various strategies have been proposed to improve diagnosis and triage of patients with chest pain at low risk, but uncertainty still exists on the optimal combination of diagnostic tools that should be used in this subset of patients.

HYPOTHESIS

The aim of this study was to evaluate the incremental benefit of continuous 12-lead ST-segment monitoring over that provided by conventional diagnostic tools in patients with chest pain.

METHODS

Of 232 consecutive patients referred because of chest pain, 52 were classified as low-risk according to the Agency for Health Care Policy and Research unstable angina guidelines and observed for 12 h with serial cardiac enzymes and electrocardiograms (ECG) (every 3 h). All patients also underwent both echocardiography at entry and continuous 12-lead ST-segment monitoring during the observation period.

RESULTS

During a mean hospital stay of 3.7 days (range 1-14 days), a benign outcome was observed in 37 patients (71%), whereas 15 patients (29%) had major cardiac events or recurrence of chest pain of ischemic origin. Addition of ST-segment monitoring findings to baseline clinical data as well as to serial enzymes and ECG features added significant incremental prognostic value (p < 0.001). Multivariate analysis showed reproduction of pain by chest pressure (p < 0.05) and presence of ST-segment changes (> or = 0.1 mV) during 12-lead ST-segment monitoring (p < 0.001) as independent predictors of a benign or unfavorable outcome.

CONCLUSIONS

In low-risk patients with chest pain, continuous 12-lead ST-segment monitoring provides significant incremental diagnostic and prognostic information to currently used clinical, enzymatic, and ECG data, and is helpful in identifying the subset of patients with a worse in-hospital outcome.

Prevalence of life-threatening arrhythmias in ED patients transported to the radiology suite while monitored by telemetry

OBJECTIVE

The aim of this study was to determine the prevalence of life-threatening arrhythmias in monitored ED patients while in the radiology suite.

METHODS

This is a retrospective analysis at a tertiary care hospital with an ED census of 52,000 visits. The patient population consisted of 3,051 adult ED patients with a chief complaint of chest pain, who were monitored with telemetry while they were sent to the radiology suite, and who were ultimately admitted to the hospital.

RESULTS

Of a total of 3,051 consecutive patients with a cardiac presentation who received a nonportable chest x-ray, no patients were found to have incurred a life-threatening arrhythmia while in the radiology suite.

CONCLUSION

The prevalence of a cardiac arrhythmia occurring during transport or while within the radiology suite in our study was zero. We conclude that stable patients can probably be transported to radiology safely without the use of bedside telemetry.

Exercise testing in chest pain units: rationale, implementation, and results

Chest pain units are now established centers for assessment of low-risk patients presenting to the emergency department with symptoms suggestive of acute coronary syndrome. Accelerated diagnostic protocols, of which treadmill testing is a key component, have been developed within these units for efficient evaluation of these patients. Studies of the last decade have established the utility of early exercise testing,which has been safe, accurate, and cost-effective in this setting. Specific diagnostic protocols vary, but most require 6 to 12 hours of observation by serial electrocardiography and cardiac injury markers to exclude infarction and high-risk unstable angina before proceeding to exercise testing. However, in the chest pain unit at UC Davis Medical Center,the approach includes "immediate" treadmill testing without a traditional process to rule out myocardial infarction. Extensive experience has validated this approach in a large, heterogeneous population. The optimal strategy for evaluating low-risk patients presenting to the emergency department with chest pain will continue to evolve based on current research and the development of new methods.

A Computer Based Telemedicine Protocol to Predict Acute Coronary Syndrome in Patients With Chest Pain at Home

The decision to admit a patient to a coronary care unit for acute coronary syndrome (ACS) has serious medical and financial consequences. In this study, we aimed to develop a computer program to predict the existence of ACS in patients with chest pain at home; it is intended that patients will be able to access the program via the website to test its validity. This study proceeded in two phases. In the first phase, a computer-based decision protocol was developed using recursive-partitioning analysis to predict ACS in 250 patients with chest pain on the basis of their historical data. In the second phase, this protocol was tested in 115 patients for diagnosis of ACS prospectively. Thirty-two of the patients answered the algorithm questions on the website. All of the patients who visited the website of this study were advised to go to the emergency department. Although the algorithm showed the presence of ACS in 82 of 115 patients, 60 of 115 patients were diagnosed as having ACS in the emergency department (n = 55) or at follow-up. The agreement between the diagnosis of the algorithm and the true diagnosis was moderate and statistically significant (Kappa coefficient 0.61, P < 0.001). The sensitivity of the algorithm was 100%, although its specificity was 60%. The accuracy of the algorithm in diagnosing ACS was 81%. The algorithm diagnoses patients with ACS at a high ratio and decreases the number of patients being unnecessarily admitted to the emergency with non-ACS.

Lack of utility of telemetry monitoring during transport to inpatient beds for identification of dysrhythmias for emergency department patients with potential and known acute coronary syndromes

Patients admitted with acute and potential acute coronary syndromes (ACS) frequently required accompaniment by a registered nurse from the emergency department (ED) to inpatient telemetry beds. We tested the hypothesis that telemetry transport monitoring for patients with acute and potential ACS is of limited utility. We conducted a prospective cohort study of patients who were admitted from the ED with acute and potential ACS. Endpoints were life threatening ventricular dysrhythmias requiring intervention and duration of transport time. The setting was an urban tertiary-care emergency department with 55,000 annual visits, and the subjects were adult patients admitted from the ED to inpatient beds (intensive care unit or floor telemetry) with ACS and potential ("rule-out") ACS. Main outcome measures were the development of a life threatening ventricular dysrhythmias during transport, any intervention by the transporting nurse, and the total transport time. Of 315 total admissions involving 310 patients, there were no life threatening ventricular dysrhythmias and interventions during transport [0%; 95% confidence interval 0-0.95%]. The total nurse time out of the ED spent transporting was 13.6 minutes (SD 5.2, range 4-40). The routine use of nurses accompanying patients admitted with acute and potential acute coronary syndromes is of limited utility. Patient transportation without nurses may help alleviate ED overcrowding by saving almost 15 minutes of nursing time currently being used for transport without measurable benefit.

Inpatient Telemetry Does Not Need To Be Used in the Management of Older Patients Hospitalized With Chest Pain at Low Risk for In-Hospital Coronary Events and Mortality

BACKGROUND

Little is known about patients admitted with chest pain to inpatient telemetry units directly from an emergency department.

METHODS

We analyzed data from 105 consecutive patients who presented with chest pain to an emergency department and who were hospitalized in an inpatient telemetry unit but who were at low risk for a coronary event.

RESULTS

Telemetry yielded no information which was used to manage any patient. None of the 105 patients (0%) developed a myocardial infarction or died during hospitalization. At 4.8-year follow-up, 8 of 105 patients (8%) died. Significant risk factors for long-term mortality were age (p < .001), prior coronary artery disease (p < .05), and diabetes (p < .02).

CONCLUSIONS

Inpatient telemetry was of no value in predicting short-term coronary events or mortality or long-term mortality in low-risk patients hospitalized with chest pain.

Are we appropriately triaging patients with unstable angina?

BACKGROUND

It is uncertain how aggressively patients should be monitored and admitted to the hospital for chest pain syndromes and if the monitoring itself affects patient care, process, or outcomes. We assessed the appropriateness of care based on retrospective analysis of admission bed assignment (nonmonitored vs monitored) and Thrombolysis in Myocardial Infarction (TIMI) risk score in patients from the Global Unstable Angina Registry and Treatment Evaluation (GUARANTEE) Registry.

METHODS

Baseline characteristics, process of care, and outcomes were compared among 2939 patients admitted to 1 of 35 hospitals in the United States. Patients were stratified into low (0-2), intermediate (3 or 4), and high (5-7) risk based on TIMI risk score.

RESULTS

Among the patients, 92 (3%) were admitted to the cardiac care unit (CCU), 1602 (56%) were admitted to the telemetry unit, and 1163 (41%) were admitted to an unmonitored bed. Paradoxically, high-risk patients comprised only 1% of those in the CCU, 5% of those in telemetry, and 10% of those in nonmonitored units. Conversely, low-risk patients were 64% of those in the CCU, 53% of those in telemetry, and 42% of those in unmonitored beds. Procedures were done more often on patients admitted to nonmonitored units than those on telemetry or in the CCU irrespective of TIMI risk score.

CONCLUSIONS

This registry suggests that triage of patients does not routinely follow the risk-based approach suggested in the American College of Cardiology and American Heart Association guidelines and could therefore potentially lead to inefficiencies in care. Better implementation of risk stratification for acute coronary syndrome evaluation and management is necessary.

Acute resting myocardial perfusion imaging in patients with diabetes mellitus: results from the Emergency Room Assessment of Sestamibi for Evaluation of Chest Pain (ERASE Chest Pain) trial

BACKGROUND

Resting myocardial perfusion imaging (MPI) improves the triage of patients presenting to the emergency department (ED) with symptoms suggestive of acute cardiac ischemia (ACI). In the ED setting the presence of diabetes mellitus (DM) is a predictor of ACI and hospitalization, but the role of resting MPI in patients with DM is unknown.

METHODS AND RESULTS

A secondary data analysis of a prospective, multicenter, randomized, controlled trial of ED evaluation strategies in patients with symptoms suggestive of ACI and normal or nondiagnostic electrocardiograms was performed. In the main trial 2475 patients were randomized to receive either the usual ED evaluation strategy (n = 1260) or the usual strategy supplemented by results from resting MPI by use of single photon emission computed tomography (SPECT) technetium 99m sestamibi (n = 1215). Patients with diabetes (n = 341) were evaluated separately. Imaging results, final diagnoses, effect on triage, and prognostic value of the SPECT imaging were compared between diabetic and nondiabetic patients. Of the 341 patients with diabetes, 153 (45%) were randomized to the imaging strategy. Patients with DM had higher rates of hospitalization (66% vs 49.6%, P = .0001) and ACI (21.1% vs 12.0%, P < .001) than patients without DM. Among diabetic patients without ACI, the admission rate was 63% in the usual strategy group versus 54% in the imaging strategy group (relative risk [RR] = 0.91 [95% CI, 0.76-1.06]; P = .24). There was no difference in the magnitude of this reduced risk of admission compared with patients without DM (RR = 0.84 [95% CI, 0.77-0.92]; P = .0002 for patients without DM and P = .35 for interaction of diabetes and RR reduction).

CONCLUSIONS

Acute resting MPI with Tc-99m sestamibi is associated with improved triage decision making in symptomatic ED patients with diabetes.