Cost-effectiveness of a coronary care unit versus an intermediate care unit for emergency department patients with chest pain

The Impact of Step-Down Unit Care on Patient Outcomes After ICU Discharge

Supplemental Digital Content is available in the text.

Objectives:

To examine whether and how step-down unit admission after ICU discharge affects patient outcomes.

Design:

Retrospective study using an instrumental variable approach to remove potential biases from unobserved differences in illness severity for patients admitted to the step-down unit after ICU discharge.

Setting:

Ten hospitals in an integrated healthcare delivery system in Northern California.

Patients:

Eleven-thousand fifty-eight episodes involving patients who were admitted via emergency departments to a medical service from July 2010 to June 2011, were admitted to the ICU at least once during their hospitalization, and were discharged from the ICU to the step-down unit or the ward.

Interventions:

None.

Measurements and Main Results:

Using congestion in the step-down unit as an instrumental variable, we quantified the impact of step-down unit care in terms of clinical and operational outcomes. On average, for ICU patients with lower illness severity, we found that availability of step-down unit care was associated with an absolute decrease in the likelihood of hospital readmission within 30 days of 3.9% (95% CI, 3.6–4.1%). We did not find statistically significant effects on other outcomes. For ICU patients with higher illness severity, we found that availability of step-down unit care was associated with an absolute decrease in in-hospital mortality of 2.5% (95% CI, 2.3–2.6%), a decrease in remaining hospital length-of-stay of 1.1 days (95% CI, 1.0–1.2 d), and a decrease in the likelihood of ICU readmission within 5 days of 3.6% (95% CI, 3.3–3.8%).

Conclusions:

This study shows that there exists a subset of patients discharged from the ICU who may benefit from care in an step-down unit relative to that in the ward. We found that step-down unit care was associated with statistically significant improvements in patient outcomes especially for high-risk patients. Our results suggest that step-down units can provide effective transitional care for ICU patients.

Cost-Effectiveness of Cardiac Rehabilitation in Patients with Coronary Artery Disease: A Meta-Analysis

BACKGROUND

Medical costs associated with cardiovascular disease are increasing considerably worldwide; therefore, an efficacious, cost-effective therapy which allows the effective use of medical resources is vital. There have been few economic evaluations of cardiac rehabilitation (CR), especially meta-analyses of medical cost versus patient outcome.

METHODS

The target population in this meta-analysis included convalescent and comprehensive CR patients with coronary artery disease (CAD), the status most commonly observed postmyocardial infarction (MI). Here, we evaluated medical costs, quality-adjusted life year (QALY), cost-effectiveness, mortality, and life year (LY). Regarding cost-effectiveness analysis, we analyzed medical costs per QALY, medical costs per LY, and the incremental cost-utility ratio (ICUR). We then examined the differences in effects for the 2 treatment arms (CR vs. usual care (UC)) using the risk ratio (RR) and standardized mean difference (SMD).

RESULTS

We reviewed 59 studies and identified 5 studies that matched our selection criteria. In total, 122,485 patients were included in the analysis. Meta-analysis results revealed that the CR arm significantly improved QALY (SMD: -1.78; 95% confidence interval (CI): -2.69, -0.87) compared with UC. Although medical costs tended to be higher in the CR arm compared to the UC arm (SMD: 0.02; 95% CI: -0.08, 0.13), cost/QALY was significantly improved in the CR arm compared with the UC arm (SMD: -0.31; 95% CI: -0.53, -0.09). The ICURs for the studies (4 RCTs and 1 model analysis) were as follows: -48,327.6 USD/QALY; -5,193.8 USD/QALY (dominant, CR is cheaper and more effective than UC); and 4,048.0 USD/QALY, 17,209.4 USD/QALY, and 26,888.7 USD/QALY (<50,000 USD/QALY, CR is costlier but more effective than UC), respectively. Therefore, there were 2 dominant and 3 effective results.

CONCLUSIONS

While there are some limitations, primarily regarding data sources, our results suggest that CR is potentially cost-effective.

Speckle tracking imaging as a predictor of left ventricular remodeling 6 months after first anterior ST elevation myocardial infarction in patients managed by primary percutaneous coronary intervention

Acute myocardial infarction (AMI) remains a leading cause of morbidity and mortality worldwide. LV remodeling is an important factor in the pathophysiology of advancing heart failure (HF).

Aim of the work

To evaluate the value of speckle tracking imaging as a predictor of left ventricular remodeling 6 months after first anterior STEMI in patients managed by primary PCI.

Methodology

Eighty-five patients with first acute anterior STEMI underwent primary PCI. Patients were followed up for 6 months. Echocardiographywas done within 48 h [1] Standard transthoracic 2D echocardiographic examination: LV internal dimensions and volumes, Left Ventricular EF, and Wall Motion Score Index: [2] LV peak systolic global longitudinal strain and Torsion dynamics were assessed. Echocardiography was repeated at 6 months LV volumes and EF were calculated. LV remodeling was defined as an increase in LV EDV ≥ 20% 6 months after infarction as compared to baseline data. Patients were then classified into Group I: did not develop LV remodeling. Group II: developed LV remodeling. Both groups were studied to determine predictors of LV remodeling.

Results

At baseline echocardiographic evaluation there was no statistically significant difference between both groups regarding both LVEDD and LVEDV, while there was statistically significant increase in both LV ESD and LV ESV, with statistically significant lower Ejection Fraction, in LV remodeling group. There was also statistically significant higher LV peak systolic GLS values in LV remodeling group, the best cut-off value was >−12.5 (Sensitivity 87%, Specificity 85%) and LV torsion was also statistically significantly lower in the LV remodeling group, with the best cut-off value for LV torsion was <9.5°, [Sensitivity 91%, Specificity 85%].

Independent predictors of LV remodeling after AMI: baseline WMSI > 1.8, baseline LV EF < 40, GLS > −12.5%, LV torsion < 9.5°, CK-MB > 500 U/L, baseline Thrombus grade > 4 and total ischemic time.

Conclusion

Average peak systolic GLS and LV torsion at echocardiography done early after myocardial infarction are independent predictors of LV remodeling after anterior STEMI and can be used to predict occurrence of LV remodeling after 6 months.

Myocardial performance index as an echocardiographic predictor of early in-hospital heart failure during first acute anterior ST-elevation myocardial infarction

Objectives

To determine the value of Myocardial Performance Index (MPI) as an echocardiographic predictor of early in-hospital heart failure (HF) during first acute anterior ST-Elevation Myocardial Infarction (STEMI).

Background

Myocardial infarction induces variable degrees of impairment in left ventricular (LV) systolic and diastolic functions. The ejection fraction (EF) and transmitral flow, the most frequently used methods for evaluation of systolic and diastolic functions respectively, both have considerable limitations. The MPI is a single parameter, capable of estimating combined systolic and diastolic performance and lacks such limitations.

Methods

We enrolled 60 patients presented with a first acute anterior STEMI who have undergone primary PCI. Echocardiography was done within 24 h of chest pain with measurement of MPI. The LV MPI was calculated as (isovolumic contraction time “ICT” + relaxation time “IRT”)/Ejection time “ET”. Besides, clinical and echocardiographic variables were analyzed and CHF was defined as Killip class ≥ II.

Results

Early in-hospital HF occurred in 23 of patients (38%). Ejection fraction was found to have a highly significant negative correlation with the development of in-hospital HF (p = .0001), while MPI was found to have a highly significant positive correlation (p = .0001). A cut-off point of MPI > 0.73 showed a very high specificity (94.6%) and sensitivity (78.3%) for identifying patients with HF. On the other hand, a cut-off point of EF ≤ 33% has shown 94.6% specificity and 56.5% sensitivity for HF prediction.

Conclusions

The MPI might be a strong predictor of in-hospital HF after first acute anterior STEMI.

Emergency Physician Risk Estimates and Admission Decisions for Chest Pain: A Web-Based Scenario Study

STUDY OBJECTIVE

We conducted this study to better understand how emergency physicians estimate risk and make admission decisions for patients with low-risk chest pain.

METHODS

We created a Web-based survey consisting of 5 chest pain scenarios that included history, physical examination, ECG findings, and basic laboratory studies, including a negative initial troponin-level result. We administered the scenarios in random order to emergency medicine residents and faculty at 11 US emergency medicine residency programs. We randomized respondents to receive questions about 1 of 2 endpoints, acute coronary syndrome or serious complication (death, dysrhythmia, or congestive heart failure within 30 days). For each scenario, the respondent provided a quantitative estimate of the probability of the endpoint, a qualitative estimate of the risk of the endpoint (very low, low, moderate, high, or very high), and an admission decision. Respondents also provided demographic information and completed a 3-item Fear of Malpractice scale.

RESULTS

Two hundred eight (65%) of 320 eligible physicians completed the survey, 73% of whom were residents. Ninety-five percent of respondents were wholly consistent (no admitted patient was assigned a lower probability than a discharged patient). For individual scenarios, probability estimates covered at least 4 orders of magnitude; admission rates for scenarios varied from 16% to 99%. The majority of respondents (>72%) had admission thresholds at or below a 1% probability of acute coronary syndrome. Respondents did not fully differentiate the probability of acute coronary syndrome and serious outcome; for each scenario, estimates for the two were quite similar despite a serious outcome being far less likely. Raters used the terms "very low risk" and "low risk" only when their probability estimates were less than 1%.

CONCLUSION

The majority of respondents considered any probability greater than 1% for acute coronary syndrome or serious outcome to be at least moderate risk and warranting admission. Physicians used qualitative terms in ways fundamentally different from how they are used in ordinary conversation, which may lead to miscommunication during shared decisionmaking processes. These data suggest that probability or utility models are inadequate to describe physician decisionmaking for patients with chest pain.

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.

Sex differences in in-hospital mortality following a first acute myocardial infarction: symptomatology, delayed presentation, and hospital setting

BACKGROUND

Women generally wait longer than men prior to seeking treatment for acute myocardial infarction (AMI). They are more likely to present with atypical symptoms, and are less likely to be admitted to coronary or intensive care units (CCU or ICU) compared to similarly-aged males. Women are more likely to die during hospital admission. Sex differences in the associations of delayed arrival, admitting ward, and mortality have not been thoroughly investigated.

METHODS

Focusing on presenting symptoms and time of presentation since symptom onset, we evaluated sex differences in in-hospital mortality following a first AMI in 4859 men and women presenting to three emergency departments (ED) from December 2008 to February 2014. Sex-specific risk of mortality associated with admission to either CCU/ICU or medical wards was calculated after adjusting for age, socioeconomic status, triage-assigned urgency of presentation, blood pressure, heart rate, presenting symptoms, timing of presentation since symptom onset, and treatment in the ED. Sex-specific age-adjusted attributable risks were calculated.

RESULTS

Compared to males, females waited longer before seeking treatment, presented more often with atypical symptoms, and were less likely to be admitted to CCU or ICU. Age-adjusted mortality in CCU/ICU or medical wards was higher among females (3.1 and 4.9 % respectively in CCU/ICU and medical wards in females compared to 2.6 and 3.2 % in males). However, after adjusting for variation in presenting symptoms, delayed arrival and other risk factors, risk of death was similar between males and females if they were admitted to CCU or ICU. This was in contrast to those admitted to medical wards. Females admitted to medical wards were 89 % more likely to die than their male counterparts. Arriving in the ED within 60 min of onset of symptoms was not associated with in-hospital mortality. Among males, 2.2 % of in-hospital mortality was attributed to being admitted to medical wards rather than CCU or ICU, while for females this age-adjusted attributable risk was 4.1 %.

CONCLUSIONS

Our study stresses the need to reappraise decision making in patient selection for admission to specialised care units, whilst raising awareness of possible sex-related bias in management of patients diagnosed with an AMI.

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.

Myocardial infarction false alarm: initial electrocardiogram and cardiac enzymes

OBJECTIVE

The objectives of this study were to determine the incidence of a myocardial infarction "false alarm" and evaluate the efficacy of the initial electrocardiogram and cardiac enzymes in diagnosing myocardial infarction in Malaysia.

METHODS

We recruited patients who were admitted with suspected myocardial infarction from June to August 2008. The medical records of these patients were reviewed for the initial electrocardiogram, initial cardiac enzyme levels (creatinine kinase-MB and troponin T), and the final diagnosis upon discharge. The subjects were stratified into 2 groups: true myocardial infarction, and false alarm.

RESULTS

125 patients were enrolled in this study. Following admission and further evaluation, the diagnosis was revised from myocardial infarction to other medical conditions in 48 (38.4%) patients. The sensitivity and specificity of the initial ischemic electrocardiographic changes were 54.5% and 70.8%, respectively. Raised cardiac enzymes had a sensitivity of 44.3% and specificity of 95.8%.

CONCLUSION

A significant proportion of patients in Malaysia are admitted with a false-alarm myocardial infarction. The efficacy of the electrocardiogram in diagnosing myocardial infarction in Malaysia was comparable to the findings of Western studies, but the cardiac enzymes had a much lower sensitivity.

Automated detection of healthy and diseased aortae from images obtained by contrast-enhanced CT scan

PURPOSE

We developed the next stage of our computer assisted diagnosis (CAD) system to aid radiologists in evaluating CT images for aortic disease by removing innocuous images and highlighting signs of aortic disease.

MATERIALS AND METHODS

Segmented data of patient's contrast-enhanced CT scan was analyzed for aortic dissection and penetrating aortic ulcer (PAU). Aortic dissection was detected by checking for an abnormal shape of the aorta using edge oriented methods. PAU was recognized through abnormally high intensities with interest point operators.

RESULTS

The aortic dissection detection process had a sensitivity of 0.8218 and a specificity of 0.9907. The PAU detection process scored a sensitivity of 0.7587 and a specificity of 0.9700.

CONCLUSION

The aortic dissection detection process and the PAU detection process were successful in removing innocuous images, but additional methods are necessary for improving recognition of images with aortic disease.

CTA in the evaluation of acute chest pain syndromes. Should more widespread use be advocated?

INTRODUCTION

With the advent of CT more than 3 decades ago, we have seen rapid evolution of this technology, so that we are now able to noninvasively accurately image the coronary arterial tree. This has opened up a debate as to the role of this imaging modality in our day-to-day evaluation of acute coronary syndromes. Much recent literature has focused on whether in the acute setting this modality should be incorporated into current evaluation and treatment guidelines.

AREAS COVERED

A comprehensive review of a literature illustrating the utility of CTA in the acute care setting is presented. The paper goes on to address the benefits and challenges of implementation of CTA in the evaluation of acute chest pain syndromes. Alternative guidelines and insights on future directions are presented.

EXPERT OPINION

In this current era where CAD, and more specifically acute chest pain syndromes, remains as a large part of ED visits and also healthcare costs, CTA will play an important role in the diagnosis and treatment of individuals. It remains only a matter of time when this will be implemented in our guidelines, in light of the recent literature and ever improving CTA protocols.

Coronary CT and the coronary calcium score, the future of ED risk stratification?

Accurate and efficient evaluation of acute chest pain remains clinically challenging because traditional diagnostic modalities have many limitations. Recent improvement in non-invasive imaging technologies could potentially improve both diagnostic efficiency and clinical outcomes of patients with acute chest pain while reducing unnecessary hospitalizations. However, there is still controversy regarding much of the evidence for these technologies. This article reviews the role of coronary artery calcium score and the coronary computed tomography in the assessment of individual coronary risk and their usefulness in the emergency department in facilitating appropriate disposition decisions. The evidence base and clinical applications for both techniques are also described, together with cost- effectiveness and radiation exposure considerations.

The evolution of chest pain pathways

Patients presenting to the emergency department with chest pain require prompt identification and referral, as early treatment of patients with an acute coronary syndrome (ACS) is crucial to decrease morbidity and mortality (Steurer et al, Emerg Med J. 2010;27:896-902). Although rule-in ACS is critical and time dependant, other difficulties arise during the rule-out ACS process (Steurer et al, Emerg Med J. 2010;27:896-902). Inappropriate discharge of patients with misdiagnosed acute myocardial infarction is associated with significant morbidity and mortality. Concerns relating to inappropriate discharge result in readmission with resultant lengthy hospital stays, high costs, and contribute to overcrowding and bed block (Amsterdam et al, J Am Coll Cardiol. 2002;40:251-256; Cardiol Clin. 2005;23:503-516; Furtado et al, Emerg Med. In press; Karlson, Am J Cardiol. 1991;68:171-175; Ng et al, Am J Cardiol. 2001;88:611-617; Ramakrishna et al, Mayo Clin Proc. 2005;80:322-329; Stowers, Crit Pathw Cardiol. 2003;2:88-94). The challenge of chest pain diagnosis has led to a number of associated problems within the health care system. The growing need for improvements in consistency of patient care, resource efficiency, and quality of patient healthcare has led to the development of chest pain pathways (Erhardt et al, Eur Heart J. 2002;23:1153-1176). The development and implementation of chest pain pathways is not without difficulties. These may arise from differences in the management approaches of health practitioners, poor adherence to guidelines, and concerns for costs. New procedures such as new cardiac injury markers, stress testing, and specialized chest pain units have led to a reduction in admission rates and length of stay, reduced costs, and a reduction of inappropriate discharge of patients with ischemic heart disease.

A meta-analysis of 64-section coronary CT angiography findings for predicting 30-day major adverse cardiac events in patients presenting with symptoms suggestive of acute coronary syndrome

RATIONALE AND OBJECTIVES

To determine the accuracy of 64-section coronary computed tomography angiography (CCTA) in predicting 30 day major adverse cardiac events (MACE) for patients presenting with symptoms concerning for acute coronary syndrome (ACS).

MATERIALS AND METHODS

Electronic databases between January 1, 2005, and May, 1, 2011, and reference lists from relevant published research articles were searched. We included studies on adult patients who presented with active symptoms suggestive of ACS, had immediate 64-section CCTA performed and were assessed for MACE at a minimum of 30 days past their initial presentation. Studies had to report or provide sufficient detail to determine sensitivity, specificity, positive predictive value, and negative predictive value in relation to MACE using a 50% diameter stenosis as cutoff criterion for coronary artery disease.

RESULTS

Nine studies were included for a total of 1559 patients studied (42.3% women, mean age 51.9 ± 10.6). Patients ranged from low to intermediate risk for ACS. All had initial inconclusive electrocardiograms and negative cardiac biomarker results. A total of 14.8% of patients had a positive CCTA result. The pooled sensitivity was 93.3% (95% CI 88.3%-96.6%), specificity was 89.9% (95% CI 88.3%-91.3%), positive predictive value was 48.1% (95% CI 42.5%-53.8%), and negative predictive value was 99.3% (95% CI 98.7%-99.6%).

CONCLUSION

Sixty-four section CCTA had a 99.3% negative predictive value in excluding MACE for 30 days after initial symptom presentation in 85.2% of our study population. Although the value of 64-section CCTA is best for identifying patients who can safely be discharged home, it is less useful for patients who have positive results.

Differential modulation of right ventricular strain and right atrial mechanics in mild vs. severe pressure overload

Increased right atrial (RA) and ventricular (RV) chamber volumes are a late maladaptive response to chronic pulmonary hypertension. The purpose of the current investigation was to characterize the early compensatory changes that occur in the right heart during chronic RV pressure overload before the development of chamber dilation. Magnetic resonance imaging with radiofrequency tissue tagging was performed on dogs at baseline and after 10 wk of pulmonary artery banding to yield either mild RV pressure overload (36% rise in RV pressure; n = 5) or severe overload (250% rise in RV pressure; n = 4). The RV free wall was divided into three segments within a midventricular plane, and circumferential myocardial strain was calculated for each segment, the septum, and the left ventricle. Chamber volumes were calculated from stacked MRI images, and RA mechanics were characterized by calculating the RA reservoir, conduit, and pump contribution to RV filling. With mild RV overload, there were no changes in RV strain or RA function. With severe RV overload, RV circumferential strain diminished by 62% anterior (P = 0.04), 42% inferior (P = 0.03), and 50% in the septum (P = 0.02), with no change in the left ventricle (P = 0.12). RV filling became more dependent on RA conduit function, which increased from 30 ± 9 to 43 ± 13% (P = 0.01), than on RA reservoir function, which decreased from 47 ± 6 to 33 ± 4% (P = 0.04), with no change in RA pump function (P = 0.94). RA and RV volumes and RV ejection fraction were unchanged from baseline during either mild (P > 0.10) or severe RV pressure overload (P > 0.53). In response to severe RV pressure overload, RV myocardial strain is segmentally diminished and RV filling becomes more dependent on RA conduit rather than reservoir function. These compensatory mechanisms of the right heart occur early in chronic RV pressure overload before chamber dilation develops.

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."

Is coronary computed tomography angiography a resource sparing strategy in the risk stratification and evaluation of acute chest pain? Results of a randomized controlled trial

OBJECTIVES

Annually, almost 6 million U.S. citizens are evaluated for acute chest pain syndromes (ACPSs), and billions of dollars in resources are utilized. A large part of the resource utilization results from precautionary hospitalizations that occur because care providers are unable to exclude the presence of coronary artery disease (CAD) as the underlying cause of ACPSs. The purpose of this study was to examine whether the addition of coronary computerized tomography angiography (CCTA) to the concurrent standard care (SC) during an index emergency department (ED) visit could lower resource utilization when evaluating for the presence of CAD.

METHODS

Sixty participants were assigned randomly to SC or SC + CCTA groups. Participants were interviewed at the index ED visit and at 90 days. Data collected included demographics, perceptions of the value of accessing health care, and clinical outcomes. Resource utilization included services received from both the primary in-network and the primary out-of-network providers. The prospectively defined primary endpoint was the total amount of resources utilized over a 90-day follow-up period when adding CCTA to the SC risk stratification in ACPSs.

RESULTS

The mean (± standard deviation [SD]) for total resources utilized at 90 days for in-network plus out-of-network services was less for the participants in the SC + CCTA group ($10,134; SD ±$14,239) versus the SC-only group ($16,579; SD ±$19,148; p = 0.144), as was the median for the SC + CCTA ($4,288) versus SC only ($12,148; p = 0.652; median difference = -$1,291; 95% confidence interval [CI] = -$12,219 to $1,100; p = 0.652). Among the 60 total study patients, only 19 had an established diagnosis of CAD at 90 days. However, 18 (95%) of these diagnosed participants were in the SC + CCTA group. In addition, there were fewer hospital readmissions in the SC + CCTA group (6 of 30 [20%] vs. 16 of 30 [53%]; difference in proportions = -33%; 95% CI = -56% to -10%; p = 0.007).

CONCLUSIONS

Adding CCTA to the current ED risk stratification of ACPSs resulted in no difference in the quantity of resources utilized, but an increased diagnosis of CAD, and significantly less recidivism and rehospitalization over a 90-day follow-up period.

Clinical perspective of coronary computed tomographic angiography in diagnosis of coronary artery disease

Since a 4-detector row coronary computed tomographic angiography (CCTA) was launched in 1998, CCTA has experienced rapid improvement of imaging qualities with the ongoing evolution of computed tomography (CT) technology. The diagnostic accuracy of CCTA to detect coronary artery stenosis is well established, whereas improvements are still needed to reduce the overestimation of coronary artery disease (CAD) and assess plaque composition. CCTA has been used to evaluate CAD in various clinical settings. For example, CCTA could be an efficient initial triage tool at emergency departments for patients with acute chest pain with low-to-intermediate risk because of its high negative predictive value. In patients with suspected CAD, CCTA could be a cost-effective alternative to myocardial perfusion imaging and exercise electrocardiogram for the initial coronary evaluation of patients with intermediate pre-test likelihood suspected CAD. However, in asymptomatic populations, there is a lack of studies that show an improved prognostic power of CCTA over other modalities. Therefore, the clinical use of CCTA to detect CAD for purposes of risk stratification in asymptomatic individuals should be discouraged. As CT technology evolves, CCTA will provide better quality coronary imaging and non-coronary information with lower radiation exposure. Future studies should cover these ongoing technical improvements and evaluate the prognostic power of CCTA in various clinical settings of CAD in large, well-designed, randomized trials.

Low-risk patients with chest pain in the emergency department: negative 64-MDCT coronary angiography may reduce length of stay and hospital charges

OBJECTIVE

The current standard-of-care workup of low-risk patients with chest pain in an emergency department takes 12-36 hours and is expensive. We hypothesized that negative 64-MDCT coronary angiography early in the workup of such patients may enable a shorter length of stay and reduce charges.

MATERIALS AND METHODS

The standard-of-care evaluation consisted of serial cardiac enzyme tests, ECGs, and stress testing. After informed consent, we added cardiac CT early in the standard-of-care workup of 53 consecutive patients. Fifty patients had negative CT findings and were included in this series. The length of stay and charges were analyzed using actual patient data for all patients in the standard-of-care workup and for two earlier discharge scenarios based on negative cardiac CT results: First, CT plus serial enzyme tests and ECGs during an observation period followed by discharge if all were negative; and second, CT plus one set of enzyme tests and one ECG followed by discharge if all were negative. Comparisons were made using paired Student's t tests.

RESULTS

For standard of care and the two CT-based earlier discharge analyses, the mean lengths of stay were 25.4, 14.3, and 5.0 hours; mean charges were $7,597, $6,153, and $4,251. Length of stay and charges were both significantly less (p < 0.001) for the two CT-based analyses.

CONCLUSION

In low-risk patients with chest pain, discharge from the emergency department based on negative cardiac CT, enzyme tests, and ECG may significantly decrease both length of stay and hospital charges compared with the standard of care.

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.

Coronary computed tomography angiography for early triage of patients with acute chest pain: the ROMICAT (Rule Out Myocardial Infarction using Computer Assisted Tomography) trial

OBJECTIVES

This study was designed to determine the usefulness of coronary computed tomography angiography (CTA) in patients with acute chest pain.

BACKGROUND

Triage of chest pain patients in the emergency department remains challenging.

METHODS

We used an observational cohort study in chest pain patients with normal initial troponin and nonischemic electrocardiogram. A 64-slice coronary CTA was performed before admission to detect coronary plaque and stenosis (>50% luminal narrowing). Results were not disclosed. End points were acute coronary syndrome (ACS) during index hospitalization and major adverse cardiac events during 6-month follow-up.

RESULTS

Among 368 patients (mean age 53 +/- 12 years, 61% men), 31 had ACS (8%). By coronary CTA, 50% of these patients were free of coronary artery disease (CAD), 31% had nonobstructive disease, and 19% had inconclusive or positive computed tomography for significant stenosis. Sensitivity and negative predictive value for ACS were 100% (n = 183 of 368; 95% confidence interval [CI]: 98% to 100%) and 100% (95% CI: 89% to 100%), respectively, with the absence of CAD and 77% (95% CI: 59% to 90%) and 98% (n = 300 of 368, 95% CI: 95% to 99%), respectively, with significant stenosis by coronary CTA. Specificity of presence of plaque and stenosis for ACS were 54% (95% CI: 49% to 60%) and 87% (95% CI: 83% to 90%), respectively. Only 1 ACS occurred in the absence of calcified plaque. Both the extent of coronary plaque and presence of stenosis predicted ACS independently and incrementally to Thrombolysis In Myocardial Infarction risk score (area under curve: 0.88, 0.82, vs. 0.63, respectively; all p < 0.0001).

CONCLUSIONS

Fifty percent of patients with acute chest pain and low to intermediate likelihood of ACS were free of CAD by computed tomography and had no ACS. Given the large number of such patients, early coronary CTA may significantly improve patient management in the emergency department.

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.

Triple rule-out and dedicated coronary artery CTA: comparison of coronary artery image quality

RATIONALE AND OBJECTIVE

The aim of this study was to compare image quality on dedicated and triple rule-out coronary computed tomographic (CT) angiography (CTA) with respect to motion artifacts and the quality of coronary artery opacification.

MATERIALS AND METHODS

Twenty dedicated coronary CT angiographic studies and 20 emergency department triple rule-out CT angiographic studies (ie, to rule out pulmonary embolism, aortic dissection, and acute coronary syndrome) performed on 64-slice CT scanner were selected. Two radiologists, blinded to type of CTA, scored coronary artery image quality. Up to 14 coronary artery segments were scored for motion artifact on a scale ranging from 1 (no motion artifact) to 4 (severe motion artifact). The radiologists also scored the quality of opacification (1 = good opacification, 2 = limited opacification, 3 = vessel not seen). The average of all segments and dedicated larger and smaller coronary artery segments was compared.

RESULTS

The average motion-artifact scores per vessel segment for dedicated and triple rule-out studies were 1.64 and 1.72, respectively (P = .6). For larger segments, the average motion-artifact score was 1.41 for dedicated CTA compared to 1.55 for triple rule-out CTA (P = .2). The average coronary artery opacification for dedicated studies was 1.05 for all segments and 1.03 for larger segments, compared to triple rule-out studies, which had scores of 1.09 (P = .5) for all segments and 1.06 (P = .5) for larger segments. No statistically significant differences in favor of dedicated CTA were identified.

CONCLUSION

The image quality of triple rule-out CTA is comparable to that of dedicated coronary CTA, showing no statistically significant difference in motion artifacts or opacification, and therefore may be an alternative and useful diagnostic study in a select group of emergency department patients.

Evaluation of a "triple rule-out" coronary CT angiography protocol: use of 64-Section CT in low-to-moderate risk emergency department patients suspected of having acute coronary syndrome

PURPOSE

To determine whether coronary computed tomographic (CT) angiography "triple rule-out" evaluation of emergency department (ED) patients presenting with symptoms suggestive of acute coronary syndrome (ACS) can help identify a subset of patients who can be discharged without adverse clinical outcomes within 30 days.

MATERIALS AND METHODS

This protocol was approved by the university institutional review board. Each patient provided written informed consent prior to inclusion. Coronary CT angiography was performed in 201 consecutive low-to-moderate risk ACS patients. A triple rule-out protocol was used to evaluate for coronary disease, pulmonary embolism, aortic dissection, and other thoracic disease. Four patients were excluded because of technical problems. The remaining subjects underwent a 30-day follow-up.

RESULTS

A disease process other than coronary atherosclerosis that explained the presenting symptoms was diagnosed in 22 (11%) of 197 patients. Clinically important noncoronary diagnoses that did not explain patient symptoms were identified in 27 (14%) of 197 additional patients. With respect to coronary artery disease, 10 patients had severe disease (>70% stenosis), 12 had moderate disease (50%-70% stenosis), 46 had mild disease (up to 50% stenosis), and 129 had no disease. No further diagnostic testing was performed in 133 (76%) of 175 of patients with no to mild coronary disease. At 30-day follow-up, the negative predictive value of coronary CT angiography with no more than mild disease was 99.4%. There were no adverse outcomes at 30 days.

CONCLUSION

Triple rule-out coronary CT angiography evaluation of low-to-moderate risk ACS patients presenting to the ED provided a noncoronary diagnosis that explained the presenting complaint in 11% of patients, suggested the presence of significant moderate-to-severe coronary disease in 11% (22 of 197) of patients, and precluded additional diagnostic cardiac testing in the majority of patients with no adverse outcomes at 30-day follow-up.

Can ECG-gated MDCT be considered an obligatory step to plan and manage a new chest-pain unit?

The recent improvements in multi-detector computed tomography technology and its application in cardiac field allow to consider this non-invasive imaging technique as a promising comprehensive method for detecting significant coronary stenoses in a chest-pain unit. The possibility to use the ECG-synchronisation acquisition protocol, normally limited to the cardiac volume, for the entire thoracic vascular system should have the remarkable potential to reduce invasive and non-invasive procedures actually used to investigate acute chest pain and the number of unnecessary hospital admissions without reducing appropriate admissions in patients with chest pain.

[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.

A review of health care models for coronary heart disease interventions

This article reviews models for the treatment of coronary heart disease (CHD). Whereas most of the models described were developed to assess the cost effectiveness of different treatment strategies, other models have also been used to extrapolate clinical trials, for capacity and resource planning, or to predict the future population with heart disease. In this paper we investigate the use of modelling techniques in relation to different types of health intervention, and we discuss the assumptions and limitations of these approaches. Many of the models reviewed in this paper use decision tree models for acute or short term interventions, and Markov or state transition models for chronic or long term interventions. Discrete event simulation has, however, been used for more complex whole system models, and for modelling resource-constrained interventions and operational planning. Nearly all of the studies in our review used cohort-based models rather than population based models, and therefore few models could estimate the likely total costs and benefits for a population group. Most studies used de novo purpose built models consisting of only a small number of health states. Models of the whole disease system were less common. The model descriptions were often incomplete. We recommend that the reporting of model structure, assumptions and input parameters is more explicit, to reduce the risk of biased reporting and ensure greater confidence in the model results.

The impact of alcohol, tobacco, and other drug use and abuse in the emergency department

Alcohol, tobacco, and other drug use is a significant societal problem. Individuals who use these substances are frequently seen in emergency departments at rates disproportionately greater than their population prevalence. This article highlights the impact of these drugs on patients and on emergency departments, including common presenting problems of individuals on these substances. Also discussed is how to help and to refer individuals with substance abuse problems through brief motivational interventions.

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.

Chordal Cutting Does Not Adversely Affect Left Ventricle Contractile Function

Background— Severing a limited number of second-order chordae to the anterior leaflet can improve ischemic mitral regurgitation (MR). Some concerns have been raised regarding possible influence on regional and global left ventricle (LV) function. We evaluated changes in cardiac function in 5 normal sheep with cutting of pre-instrumented chords in the beating heart to maintain constant load.

Methods and Results— Under cardiopulmonary bypass, wires were placed around the 2 central basal chordae and brought outside the heart, which was restarted. Hemodynamic and imaging data were collected before and after chordal cutting by radiofrequency ablation using those wires. Segmental contractility was assessed invasively using sonomicrometers and noninvasively using Doppler tissue velocity and strain rate (with strain rate viewed as less load-dependent than ejection fraction) at 6 sites: base, mid-ventricle, and apex along the anteroseptal and posterolateral walls. We found no changes from before to after chordal cutting in LV end-diastolic volume (47.2±3.3 after cutting versus 48.4±4.6 mL before cutting, P =0.66), end-systolic volume (21.5±1.2 versus 22.3±2.8 mL, P =0.68), ejection fraction (54.2±1.8 versus 54.2±2.7%, P =0.96), systolic ventricular elastance (7.28±1.68 versus 7.66±2.11 mm Hg/mL, P =0.64), preload-recruitable stroke work (46.6±7.7 versus 50.2±10.7 mm Hg, P =0.76), and LVdP/dt (1480±238 versus 1392±250 mm Hg/s, P =0.45). Doppler tissue velocities and longitudinal strain rates surrounding the papillary muscles were unchanged, as were sonomicrometer longitudinal and mediolateral absolute strains. No wall motion abnormalities were visible around the papillary muscles, and no MR developed.

Conclusion— We find no evidence for acutely decreased global or segmental LV contractility with chordal cutting. This absence of adverse effects is consistent with long-term clinical experience with cutting these chords in valve repair.

The risk of missed diagnosis of acute myocardial infarction associated with emergency department volume

STUDY OBJECTIVE

Missed diagnosis of acute myocardial infarction is associated with adverse clinical outcomes and more dollars recovered in malpractice suits than any other condition. The rate of missed diagnosis varies between emergency departments (EDs); we hypothesized that it is associated with the volume of acute myocardial infarction patients treated in an ED and that the association can be explained by other hospital characteristics.

METHODS

We linked the records of all acute myocardial infarction patients admitted to an Ontario hospital in 2002 to 2003 to their ED visit records in the 7 days preceding admission. Acute myocardial infarctions were defined as missed if the diagnosis on the previous visit matched a list of cardiac symptoms and illnesses. We assessed whether annual volume of admitted acute myocardial infarction patients treated in the ED (grouped as 0 to 49; 50 to 99; 100 to 199; 200 to 299; and > or = 300) was associated with missed acute myocardial infarction, adjusting for age, sex, teaching hospital status, and acute myocardial infarction severity. In a secondary analysis, we used data from a survey of Ontario EDs to assess whether hospital characteristics (triage practices, use of diagnostic tests, and consultant availability) explained the volume association.

RESULTS

Of 19,663 acute myocardial infarction patients, mean age (68.3 years), sex (63% men), and predicted 1-year mortality (mean 0.21; SD 0.18) were similar across volume groups. The rate of missed acute myocardial infarction was 2.1% (95% confidence interval [CI] 1.9% to 2.3%) and varied from 0% to 29% across EDs. Compared with very high-volume EDs, the adjusted odds ratio of missed acute myocardial infarction was 2.0 in very low- (95% CI 1.5 to 2.7) and 1.6 in low- (95% CI 1.1 to 2.3) volume EDs. Consultant availability partially explained the volume effect.

CONCLUSION

Lower-volume EDs have up to 2-fold higher odds of missed acute myocardial infarctions compared with highest-volume ones after controlling for patient factors. Many current technologies designed to increase diagnostic sensitivity are feasible only in higher-volume centers. Efforts to reduce overall rates of missed acute myocardial infarctions should instead focus on simpler solutions appropriate for lower-volume EDs, such as telemedicine to improve access to consultant expertise.

Direct hospital costs of chest pain patients attending the emergency department: a retrospective study

Background

Chest pain is one of the most common complaints in the Emergency Department (ED), but the cost of ED chest pain patients is unclear. The aim of this study was to describe the direct hospital costs for unselected chest pain patients attending the emergency department (ED).

Methods

1,000 consecutive ED visits of patients with chest pain were retrospectively included. Costs directly following the ED visit were retrieved from the hospital economy system.

Results

The mean cost per patient visit was 26.8 thousand Swedish kronar (kSEK) (median 7.2 kSEK), with admission time accounting for 73% of all costs. Mean cost for patients discharged from the ED was 1.4 kSEK (median 1.3 kSEK), and for patients without ACS admitted 1 day or less 7.6 kSEK (median 6.9 kSEK). The practice in the present study to admit 67% of the patients, of whom only 31% proved to have ACS, was estimated to give a cost per additional life-year saved by hospital admission, compared to theoretical strategy of discharging all patients home, of about 350 kSEK (39 kEUR or 42 kUSD).

Conclusion

Costs for chest pain patients are large and primarily due to admission time. The present admission practice seems to be cost-effective, but the substantial overadmission indicates that better ED diagnostics and triage could decrease costs considerably.