MEDICOLEGAL ASPECTS OF ACUTE MYOCARDIAL INFARCTION

High-Risk Chief Complaints I: Chest Pain-The Big Three (an Update)

Nontraumatic chest pain is a frequent concern of emergency department patients, with causes that range from benign to immediately life threatening. Identifying those patients who require immediate/urgent intervention remains challenging and is a high-risk area for emergency medicine physicians where incorrect or delayed diagnosis may lead to significant morbidity and mortality. This article focuses on the 3 most prevalent diagnoses associated with adverse outcomes in patients presenting with nontraumatic chest pain, acute coronary syndrome, thoracic aortic dissection, and pulmonary embolism. Important aspects of clinical evaluation, diagnostic testing, treatment, and disposition and other less common causes of lethal chest pain are also discussed.

Efficacy of High-Sensitivity Troponin T in Identifying Very-Low-Risk Patients With Possible Acute Coronary Syndrome

Importance

Physicians need information on how to use the first available high-sensitivity troponin (hsTnT) assay in the United States to identify patients at very low risk for 30-day adverse cardiac events (ACE).

Objective

To determine whether a negative hsTnT assay at 0 and 3 hours following emergency department presentation could identify patients at less than 1% risk of a 30-day ACE.

Design, Setting, and Participants

A prospective, observational study at 15 emergency departments in the United States between 2011 and 2015 that included individuals 21 years and older, presenting to the emergency department with suspected acute coronary syndrome. Of 1690 eligible individuals, 15 (no cardiac troponin T measurement) and 320 (missing a 0-hour or 3-hour sample) were excluded from the analyses.

Exposures

Serial hsTnT measurements (fifth-generation Roche Elecsys hsTnT assay).

Main Outcomes and Measures

Serial blood samples from each patient were collected after emergency department presentation (once identified as a potential patient with acute coronary syndrome) and 3 hours, 6 to 9 hours, and 12 to 24 hours later. Adverse cardiac events were defined as myocardial infarction, urgent revascularization, or death. The upper reference level for the hsTnT assay, defined as the 99th percentile, was established as 19 ng/L in a separate healthy US cohort. Patients were considered ruled out for acute myocardial infarction if their hsTnT level at 0 hours and 3 hours was less than the upper reference level. Gold standard diagnoses were determined by a clinical end point committee. Evaluation of assay clinical performance for acute myocardial infarction rule-out was prespecified; the hypothesis regarding 30-day ACE was formulated after data collection.

Results

In 1301 healthy volunteers (50.4% women; median age, 48 years), the upper reference level was 19 ng/L. In 1600 patients with suspected acute coronary syndrome (48.4% women; median age, 55 years), a single hsTnTlevel less than 6 ng/L at baseline had a negative predictive value for AMI of 99.4%. In 974 patients (77.1%) with both 0-hour and 3-hour hsTnT levels of 19 ng/L or less, the negative predictive value for 30-day ACE was 99.3% (95% CI, 99.1-99.6). Using sex-specific cutpoints, C statistics for women (0.952) and men (0.962) were similar for acute myocardial infarction.

Conclusions and Relevance

A single hsTnT level less than 6 ng/L was associated with a markedly decreased risk of AMI, while serial levels at 19 ng/L or less identified patients at less than 1% risk of 30-day ACE.

Appropriateness of Cardiac Troponin Testing: Insights from the Use of TROPonin In Acute coronary syndromes (UTROPIA) Study

OBJECTIVE

Our objective was to examine the appropriateness of cardiac troponin (cTn) testing among patients with cTn increases.

METHODS

This is a planned secondary analysis of the Use of TROPonin In Acute coronary syndromes (UTROPIA, NCT02060760) observational cohort study. Appropriateness of cTn testing was adjudicated for emergency department patients with cTn increases >99^th percentile and analyzed using both contemporary and high-sensitivity (hs) cTnI assays according to sub-specialty, diagnoses, and symptoms.

RESULTS

Appropriateness was determined from 1272 and 1078 adjudication forms completed for 497 and 422 patients with contemporary and hs-cTnI increases, respectively. Appropriateness of cTnI testing across adjudication forms was 71.5% and 72.0% for cTnI and hs-cTnI, respectively. Compared with emergency physicians, cardiologists were less likely to classify cTnI orders as appropriate (cTnI: 79% vs 56%, P < .0001; hs-cTnI: 82% vs 51%, P < .0001). For contemporary cTnI, appropriateness of 95%, 70%, and 39% was observed among adjudication forms completed by cardiologists for type 1 myocardial infarction, type 2 myocardial infarction, and myocardial injury, respectively; compared with 90%, 86%, and 71%, respectively, among emergency physicians. Similar findings were observed using hs-cTnI. Discordance in appropriateness adjudication forms occurred most frequently in cases of myocardial injury (62% both assays) or type 2 myocardial infarction (cTnI 31%; hs-cTnI 23%).

CONCLUSIONS

Marked differences exist in the perception of what constitutes appropriate clinical use of cTn testing between cardiologists and emergency physicians, with emergency physicians more likely to see testing as appropriate across a range of clinical scenarios. Discordance derives most often from cases classified as myocardial injury or type 2 myocardial infarction.

Utility of the History and Physical Examination in the Detection of Acute Coronary Syndromes in Emergency Department Patients

Chest pain accounts for approximately 6% of all emergency department (ED) visits and is the most common reason for emergency hospital admission. One of the most serious diagnoses emergency physicians must consider is acute coronary syndrome (ACS). This is both common and serious, as ischemic heart disease remains the single biggest cause of death in the western world. The history and physical examination are cornerstones of our diagnostic approach in this patient group. Their importance is emphasized in guidelines, but there is little evidence to support their supposed association. The purpose of this article was to summarize the findings of recent investigations regarding the ability of various components of the history and physical examination to identify which patients presenting to the ED with chest pain require further investigation for possible ACS. Previous studies have consistently identified a number of factors that increase the probability of ACS. These include radiation of the pain, aggravation of the pain by exertion, vomiting, and diaphoresis. Traditional cardiac risk factors identified by the Framingham Heart Study are of limited diagnostic utility in the ED. Clinician gestalt has very low predictive ability, even in patients with a non-diagnostic electrocardiogram (ECG), and gestalt does not seem to be enhanced appreciably by clinical experience. The history and physical alone are unable to reduce a patient's risk of ACS to a generally acceptable level (<1%). Ultimately, our review of the evidence clearly demonstrates that "atypical" symptoms cannot rule out ACS, while "typical" symptoms cannot rule it in. Therefore, if a patient has symptoms that are compatible with ACS and an alternative cause cannot be identified, clinicians must strongly consider the need for further investigation with ECG and troponin measurement.

Rapid Rule-Out of Acute Myocardial Injury Using a Single High-Sensitivity Cardiac Troponin I Measurement

BACKGROUND

Rapid rule-out strategies using high-sensitivity cardiac troponin assays are largely supported by studies performed outside the US in selected cohorts of patients with chest pain that are atypical of US practice, and focused exclusively on ruling out acute myocardial infarction (AMI), rather than acute myocardial injury, which is more common and associated with a poor prognosis.

METHODS

Prospective, observational study of consecutive patients presenting to emergency departments [derivation (n = 1647) and validation (n = 2198) cohorts], where high-sensitivity cardiac troponin I (hs-cTnI) was measured on clinical indication. The negative predictive value (NPV) and diagnostic sensitivity of an hs-cTnI concentration

RESULTS

In patients with hs-cTnI concentrations <99th percentile at presentation, acute myocardial injury occurred in 8.3% and 11.0% in the derivation and validation cohorts, respectively. In the derivation cohort, 27% had hs-cTnI < LoD, with NPV and diagnostic sensitivity for acute myocardial injury of 99.1% (95% CI, 97.7-99.8) and 99.0% (97.5-99.7) and an NPV for AMI or cardiac death at 30 days of 99.6% (98.4-100). In the validation cohort, 22% had hs-cTnI

CONCLUSIONS

A single hs-cTnI concentration Collapse

Key Words Collapse

MESH Headings

• Acute Disease
• Cohort Studies
• Female
• Humans
• Male
• Middle Aged
• Myocardial Ischemia/blood
• Myocardial Ischemia/diagnosis
• Troponin I/blood

Collapse

Grants

• FS/16/75/32533 British Heart Foundation
• SP/12/10/29922 British Heart Foundation
• HICG/1/40 Chief Scientist Office
• FS/16/14/32023 British Heart Foundation
• PG/15/51/31596 British Heart Foundation
• FS/10/024/28266 British Heart Foundation

Collapse

Affiliation(s)

Yader Sandoval Division of Cardiology, Hennepin County Medical Center, Minneapolis, MN Minneapolis Heart Institute, Abbott-Northwestern Hospital, Minneapolis, MN Minneapolis Medical Research Foundation, Minneapolis, MN
Stephen W Smith Minneapolis Medical Research Foundation, Minneapolis, MN Department of Emergency Medicine, Hennepin County Medical Center and University of Minnesota, MN
Anoop S V Shah BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
Atul Anand BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
Andrew R Chapman BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
Sara A Love Minneapolis Medical Research Foundation, Minneapolis, MN Department of Laboratory Medicine and Pathology, Hennepin County Medical Center and University of Minnesota, Minneapolis, MN
Karen Schulz Minneapolis Medical Research Foundation, Minneapolis, MN
Jing Cao Minneapolis Medical Research Foundation, Minneapolis, MN
Nicholas L Mills BHF Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
Fred S Apple Minneapolis Medical Research Foundation, Minneapolis, MN; Department of Laboratory Medicine and Pathology, Hennepin County Medical Center and University of Minnesota, Minneapolis, MN

Collapse

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

BACKGROUND

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

OBJECTIVE

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

DISCUSSION

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

CONCLUSIONS

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

Best Clinical Practice: Current Controversies in the Evaluation of Low-Risk Chest Pain with Risk Stratification Aids. Part 2

BACKGROUND

Chest pain accounts for 10% of emergency department (ED) visits annually, and many of these patients are admitted because of potentially life-threatening conditions. A substantial percentage of patients with chest pain are at low risk for a major cardiac adverse event (MACE).

OBJECTIVE

We investigated controversies in the evaluation of patients with low-risk chest pain, including clinical scores, decision pathways, and shared decision-making.

DISCUSSION

ED patients with chest pain who have negative biomarker results and nonischemic electrocardiograms are at low risk for MACE. With the large number of chest pain patients evaluated in the ED, several risk scores and pathways are in use based on history, electrocardiographic results, and biomarker results. The Thrombolysis in Myocardial Infarction and Global Registry of Acute Coronary Events scores are older rules with validation; however, they do not have adequate sensitivity or are not easy to use in the ED. The Vancouver chest pain and North American chest pain rules may be used for patients with undifferentiated chest pain in the ED. The Manchester Acute Coronary Syndromes rule uses eight factors, several of which are not available in the United States. The history, electrocardiography, age, risk factors, and troponin (HEART) score and pathway are easy to use, have high sensitivity and negative predictive values, and have better discriminatory capability for categorization. The use of pathways with shared decision-making involves the patient in management, shortens the duration of stay, and decreases risk to both the patient and the provider.

CONCLUSIONS

Risk stratification of ED patients with chest pain has evolved, and there are many tools available. The HEART pathway, designed for ED use, has several attributes that provide safe and efficient care for patients with chest pain.

Supply/demand type 2 myocardial infarction: should we be paying more attention?

Supply/demand (type 2) myocardial infarction is a commonly encountered clinical challenge. It is anticipated that it will be detected more frequently once high-sensitivity cardiac troponin assays are approved for clinical use in the United States. We provide a perspective that is based on available data regarding the definition, epidemiology, etiology, pathophysiology, prognosis, management, and controversies regarding type 2 myocardial infarction. Understanding these basic concepts will facilitate the diagnosis and treatment of these patients as well as ongoing research efforts.

[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.

Myeloperoxidase in the diagnosis of acute coronary syndromes: the importance of spectrum

BACKGROUND

Myeloperoxidase (MPO) is proposed for risk stratification in patients with suspected acute coronary syndromes (ACSs). We determined if MPO has diagnostic value in patients being evaluated for ACS.

METHOD

MIDAS was an 18-center prospective study enrolling suspected ACS emergency department patients who presented <8 hours after symptom onset and in whom serial cardiac markers and objective cardiac perfusion testing were planned. Blinded MPO (Biosite, Inc, San Diego, CA) and troponin I (Triage Cardio 3; Biosite, Inc) were drawn at arrival, and Troponin I (TnI) was measured at 90, 180, and 360 minutes. Final diagnoses were adjudicated by the local investigator blinded to study assay.

RESULTS

Of 1,018 patients, 54% were male, 26% black, with a mean age of 58 ± 13 years. Diagnoses were ACS in 288 (23%) and noncardiac chest pain (NCCP) in 788 (77%). Of patients with ACS, 94 (9.2%) had a myocardial infarction (MI) at presentation (69 non-ST-elevation MI, 25 ST-elevation MI), and 136 had unstable angina. Using a cutpoint of 210 ng/mL to provide 90% specificity, MPO had a sensitivity of 0.18; negative predictive value, 0.69; positive predictive value, 0.47; negative likelihood ratio, 0.91; and a positive likelihood ratio of 1.83 to differentiate ACS and NCCP. Because of the large overlap of quartiles, MPO was not clinically useful to predict serial TnI changes. The C statistics ± 95% CI for MPO differentiating ACS from NCCP and for AMI versus NCCP were 0.629 ± 0.04 and 0.666 ± 0.06, respectively.

CONCLUSIONS

Myeloperoxidase has insufficient accuracy for decision making in patients with suspected ACS.

High-risk chief complaints I: chest pain--the big three

Chest pain is one of the most frequently seen chief complaints in patients presenting to emergency departments, and is considered to be a "high-risk" chief complaint. The differential diagnosis for chest pain is broad, and potential causes range from the benign to the immediately life-threatening. Although many (if not most) emergency department patients with chest pain do not have an immediately life-threatening condition, correct diagnoses can be difficult to make, incorrect diagnoses may lead to catastrophic therapies, and failure to make a timely diagnosis may contribute to significant morbidity and mortality. Several atraumatic "high-risk" causes of chest pain are discussed in this article, including myocardial infarction and ischemia, thoracic aortic dissection, and pulmonary embolism. Also included are brief discussions of tension pneumothorax, esophageal perforation, and cardiac tamponade.

Outcomes research in cardiovascular imaging: report of a workshop sponsored by the National Heart, Lung, and Blood Institute

In July of 2008, the National Heart, Lung, and Blood Institute convened experts in noninvasive cardiovascular imaging, outcomes research, statistics, and clinical trials to develop recommendations for future randomized controlled trials of the use of imaging in: 1) screening the asymptomatic patient for coronary artery disease; 2) assessment of patients with stable angina; 3) identification of acute coronary syndromes in the emergency room; and 4) assessment of heart failure patients with chronic coronary artery disease with reduced left ventricular ejection fraction. This study highlights several possible trial designs for each clinical situation.

Outcomes research in cardiovascular imaging: report of a workshop sponsored by the National Heart, Lung, and Blood Institute

In July of 2008, the National Heart, Lung, and Blood Institute convened experts in noninvasive cardiovascular imaging, outcomes research, statistics, and clinical trials to develop recommendations for future randomized controlled trials of the use of imaging in: 1) screening the asymptomatic patient for coronary artery disease; 2) assessment of patients with stable angina; 3) identification of acute coronary syndromes in the emergency room; and 4) assessment of heart failure patients with chronic coronary artery disease with reduced left ventricular ejection fraction. This study highlights several possible trial designs for each clinical situation.

Outcomes research in cardiovascular imaging: report of a workshop sponsored by the National Heart, Lung, and Blood Institute

In July of 2008, the National Heart, Lung, and Blood Institute convened experts in noninvasive cardiovascular imaging, outcomes research, statistics, and clinical trials to develop recommendations for future randomized controlled trials of the use of imaging in: 1) screening the asymptomatic patient for coronary artery disease; 2) assessment of patients with stable angina; 3) identification of acute coronary syndromes in the emergency room; and 4) assessment of heart failure patients with chronic coronary artery disease with reduced left ventricular ejection fraction. This study highlights several possible trial designs for each clinical situation.

Outcomes research in cardiovascular imaging: report of a workshop sponsored by the National Heart, Lung, and Blood Institute

In July of 2008, the National Heart, Lung, and Blood Institute convened experts in noninvasive cardiovascular imaging, outcomes research, statistics, and clinical trials to develop recommendations for future randomized controlled trials of the use of imaging in: 1) screening the asymptomatic patient for coronary artery disease; 2) assessment of patients with stable angina; 3) identification of acute coronary syndromes in the emergency room; and 4) assessment of heart failure patients with chronic coronary artery disease with reduced left ventricular ejection fraction. This study highlights several possible trial designs for each clinical situation.

Prospective multicenter study of quantitative pretest probability assessment to exclude acute coronary syndrome for patients evaluated in emergency department chest pain units

STUDY OBJECTIVE

We compare the diagnostic accuracy of 3 methods--attribute matching, physician's written unstructured estimate, and a logistic regression formula (Acute Coronary Insufficiency-Time Insensitive Predictive Instrument, ACI-TIPI)--of estimating a very low pretest probability (< or = 2%) for acute coronary syndromes in emergency department (ED) patients evaluated in chest pain units.

METHODS

We prospectively studied 1,114 consecutive patients from 3 academic EDs, evaluated for acute coronary syndrome. Physicians collected data required for pretest probability assessment before protocol-driven chest pain unit testing. A pretest probability greater than 2% was considered "test positive." The criterion standard was the outcome of acute coronary syndrome (death, myocardial infarction, revascularization, or > 60% stenosis prompting new treatment) within 45 days, adjudicated by 3 independent reviewers.

RESULTS

Fifty-one of 1,114 enrolled patients (4.5%; 95% confidence interval [CI] 3.4% to 6.0%) developed acute coronary syndrome within 45 days, including 4 of 991 (0.4%; 95% CI 0.1% to 1.0%) patients, discharged after a negative chest pain unit evaluation result, who developed acute coronary syndrome. Unstructured estimate identified 293 patients with pretest probability less than or equal to 2%, 2 had acute coronary syndrome, yielding sensitivity of 96.1% (95% CI 86.5% to 99.5%) and specificity of 27.4% (95% CI 24.7% to 30.2%). Attribute matching identified 304 patients with pretest probability less than or equal to 2%; 1 had acute coronary syndrome, yielding a sensitivity of 98.0% (95% CI 89.6% to 99.9%) and a specificity of 26.1% (95% CI 23.6% to 28.7%). ACI-TIPI identified 56 patients; none had acute coronary syndrome, yielding sensitivity of 100% (95% CI 93.0% to 100%) and specificity of 6.1% (95% CI 4.7% to 7.9%).

CONCLUSION

In a low-risk ED population with symptoms suggestive of acute coronary syndrome, patients with a quantitative pretest probability less than or equal to 2%, determined by attribute matching, unstructured estimate, or logistic regression, may not require additional diagnostic testing.

Culturally Competent Care of Patients with Acute Chest Pain

PURPOSE

To inform nurse practitioners (NPs) about the influence of culture on patients' responses to pain using the example of acute chest pain.

DATA SOURCES

Selected clinical and research articles on pain and culture and the authors' clinical experiences providing care across a variety of cultures.

CONCLUSIONS

There is very little written and even fewer studies on the connection of culture and the response to acute chest pain. This topic needs more attention by nurse researchers. Implications for practice If NPs are not aware that some patients may not demonstrate behavior typically expected in acute myocardial infarction, they may miss the diagnosis and fail to treat or refer these patients for immediate treatment.

Detection of chest pain of non-cardiac origin at the emergency room by a new non-invasive device avoiding unnecessary admission to hospital

Recent advances in the treatment of acute coronary syndromes has raised awareness that prompt presentation for chest pain may be life saving. Most patients presenting with chest discomfort have a non-ischaemic ECG on presentation, but are routinely admitted to hospital because of diagnostic uncertainty for occult MI or ischaemia. We tested a new non-invasive device that measures central aortic pressure changes (dP/dtejc): an accepted index of myocardial performance that could be added to the diagnostic triage of ischaemia in the ER avoiding unnecessary admissions. We followed 85 patients presenting at the ER with acute chest pain. In 72 patients, negative ECG and myocardial enzyme dynamics ruled out coronary origin during the first 24 h after admission. In 8 of the 72 patients, coronary catheterisation found normal coronary arteries. In this group, average dP/dtejc was 163 (range 92-232). In 35 patients in whom the new non-invasive cardiac performance index dP/dtejc was above a threshold of >150, acute MI was ruled out. In 13 patients, acute chest pain had coronary origin confirmed by ECG and/or positive enzymes. The average dP/dtejc in this group was 117 (range 61-149). The dP/dtejc values were found to be significantly higher in patients without acute MI (p<0.001). Preliminary findings suggest that nearly 40% of patients presenting with acute chest pain could be spared the risks and costs of unnecessary hospital admission and more invasive cardiac testing by simply adding a easy to use, immediately obtained, test to the diagnostic protocol, and using a threshold of dP/dtejc>150 to rule out heart attack.

Evaluating the Patient With Chest Pain

Chest pain is one of the most common presenting symptoms in healthcare settings and one of the most difficult diagnostic challenges. A comprehensive history is the cornerstone of evaluation and diagnosis and one of the most important skills in distinguishing among the many causes of chest pain. Because the differential diagnosis for chest pain ranges from conditions as minor as muscle strain to life-threatening conditions, such as an acute myocardial infarction or dissecting thoracic aortic aneurysm, the advanced practice nurse must quickly and systematically assess the patient.

The association between clinical integration of care and transfer of veterans with acute coronary syndromes from primary care VHA hospitals

Background

Few studies report on the effect of organizational factors facilitating transfer between primary and tertiary care hospitals either within an integrated health care system or outside it. In this paper, we report on the relationship between degree of clinical integration of cardiology services and transfer rates of acute coronary syndrome (ACS) patients from primary to tertiary hospitals within and outside the Veterans Health Administration (VHA) system.

Methods

Prospective cohort study. Transfer rates were obtained for all patients with ACS diagnoses admitted to 12 primary VHA hospitals between 1998 and 1999. Binary variables measuring clinical integration were constructed for each primary VHA hospital reflecting: presence of on-site VHA cardiologist; referral coordinator at the associated tertiary VHA hospital; and/or referral coordinator at the primary VHA hospital. We assessed the association between the integration variables and overall transfer from primary to tertiary hospitals, using random effects logistic regression, controlling for clustering at two levels and adjusting for patient characteristics.

Results

Three of twelve hospitals had a VHA cardiologist on site, six had a referral coordinator at the tertiary VHA hospital, and four had a referral coordinator at the primary hospital. Presence of a VHA staff cardiologist on site and a referral coordinator at the tertiary VHA hospital decreased the likelihood of any transfer (OR 0.45, 95% CI 0.27–0.77, and 0.46, p = 0.002, CI 0.27–0.78). Conversely, having a referral coordinator at the primary VHA hospital increased the likelihood of transfer (OR 6.28, CI 2.92–13.48).

Conclusions

Elements of clinical integration are associated with transfer, an important process in the care of ACS patients. In promoting optimal patient care, clinical integration factors should be considered in addition to patient characteristics.

Impact of myocardial perfusion imaging on clinical management and the utilization of hospital resources in suspected acute coronary syndromes

Recent advances in the treatment of acute coronary syndromes has raised awareness in the community that prompt presentation for chest pain may be life saving. Each year in the United States, more than 6 million people present to the hospital with an acute chest pain, making this the most common presenting chief complaint second only to abdominal pain. Most patients presenting with chest discomfort have a non-ischaemic electrocardiogram on presentation. However, these patients are routinely admitted to hospital due to diagnostic uncertainty for occult myocardial infarction or ischaemia. As an approach to this dilemma, many hospitals have created protocols as a means of facilitating the identification of infarction and ischaemia and the safe and effective triage of patients with a chief complaint of chest pain. Myocardial perfusion imaging at rest has been shown to be highly sensitive for the detection of acute myocardial infarction, and can be supplemented with provocative testing after infarction has been excluded. Diagnostic strategies that utilize myocardial perfusion imaging for the evaluation of acute chest pain have successfully improved the triage of these patients by avoiding inadvertent discharge of patients with myocardial infarctions, and reducing unnecessary hospital admissions and overall cost and expenditure.