Characteristics and outcomes of young adults who present to the emergency department with chest pain

Pain Complaints and Intubation Risk in COVID-19: A Retrospective Cohort Study

Background Since coronavirus disease 2019 (COVID-19) emerged, increasing cases have been identified worldwide. COVID-19 continues to lead to significant morbidity and mortality, despite developing a vaccination for the disease. While much has been studied regarding the initial presentation and treatment of patients with COVID-19, to our knowledge, no study has uncovered that COVID-19-positive patients with abdominal pain are at a higher risk of requiring intubation. Methodology In this retrospective cohort study, we identified 104 patients who presented to the emergency room of a single tertiary care center with laboratory-confirmed COVID-19 between February 1, 2020, and April 27, 2020, and collected data on reported pain complaints. Results In this retrospective cohort study, the most common pain complaints were chest pain (25.5%), myalgia (23.4%), and abdominal pain (17.0%). Less common pain complaints included headaches (14.9%) and neck/back pain (6.3%). Of these pain complaints, only patients who reported having abdominal pain were more likely to be intubated (37.5% of patients with abdominal pain were intubated compared to 8.3% of patients without abdominal pain, with a p-value of 0.001). Conclusions Abdominal pain in a patient with COVID-19 infection significantly increases their chances of requiring intubation based on the results of this study.

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.

Non-traumatic chest pain in patients presenting to an urban emergency Department in sub Saharan Africa: a prospective cohort study in Tanzania

Background

Non-traumatic chest pain (NTCP) is a common reason for emergency department (ED) attendance in high-income countries, with the primary concern focused on life threatening cardiovascular diseases. There is general lack of data on aetiologies, diagnosis and management of NTPC in Sub Sahara African (SSA) countries. We aimed to describe evaluation, diagnosis and outcomes of adult patients presenting with NTCP to an urban ED in Tanzania.

Method

This was a prospective observational cohort study of consecutive adult (≥18 years) patients presenting with non-traumatic chest pain to the Emergency Medicine Department (EMD) of Muhimbili National Hospital (MNH) in Dar es salaam from September 2017 to April 2018. Structured case report form was used to collected demographics, clinical presentation, investigations, diagnosis, and EMD disposition and in hospital mortality. We determined frequency of NTCP among our patients, aetiologies, 24-h and 7-day in-hospital mortality, and predictors for mortality.

Results

We screened 29,495 adults attending EMD-MNH during the study and 389 (1.3%) presented with NTCP of these, 349 (90%) were enrolled. The median age was 45 (IQR 29–60) years and 177 (50.7%) were female. Overall, 69.1% patients received electrocardiography (ECG) in the EMD and 34.1% had a troponin test. Heart failure and pulmonary tuberculosis (PTB) were the leading hospital diagnoses (12.6% each), followed by chronic kidney disease (10%) and acute coronary syndrome (ACS) (9.6%). Total of 167 (48%) patients were admitted, and the 24-h and 7-day in-hospital mortality were 5 (3%) and 16 (9.6%) respectively. Univariate risk factors for mortality were a Glasgow Coma Scale of < 15 [RR = 3.4 (95%CI 3.2–23)], Acute Coronary Syndrome [RR = 5.7 (95% CI 1.7–11.8) and Troponin > 0.04 ng/ml [RR 2.9 (95%CI 1.2–7.3)]. Features distinguishing cardiovascular from other causes were: bradycardia [RR = 2.6 (95%CI 2.1–3.2)], heart beat awareness [RR = 2.3 (95%CI 1.7–3.2)] and history of diabetic mellitus [RR = 2.2 (95% CI 1.6–3.0)].

Conclusion

In this ED of SSA country, heart failure and pulmonary tuberculosis were the leading causes of NCTP, and ACS was present in 9.6%. NTCP in this setting carries high mortality, and ACS was the leading risk factor for death. ED providers in SSA must increasingly consider cardiovascular causes of NTCP.

Diagnostic Evaluation of Nontraumatic Chest Pain in Athletes

This article is a clinically relevant review of the existing medical literature relating to the assessment and diagnostic evaluation for athletes complaining of nontraumatic chest pain. The literature was searched using the following databases for the years 1975 forward: Cochrane Database of Systematic Reviews; CINAHL; PubMed (MEDLINE); and SportDiscus. The general search used the keywords chest pain and athletes. The search was revised to include subject headings and subheadings, including chest pain and prevalence and athletes. Cross-referencing published articles from the databases searched discovered additional articles. No dissertations, theses, or meeting proceedings were reviewed. The authors discuss the scope of this complex problem and the diagnostic dilemma chest pain in athletes can provide. Next, the authors delve into the vast differential and attempt to simplify this process for the sports medicine physician by dividing potential etiologies into cardiac and noncardiac conditions. Life-threatening causes of chest pain in athletes may be cardiac or noncardiac in origin, which highlights the need for the sports medicine physician to consider pathology in multiple organ systems simultaneously. This article emphasizes the importance of ruling out immediately life threatening diagnoses, while acknowledging the most common causes of noncardiac chest pain in young athletes are benign. The authors propose a practical algorithm the sports medicine physician can use as a guide for the assessment and diagnostic work-up of the athlete with chest pain designed to help the physician arrive at the correct diagnosis in a clinically efficient and cost-effective manner.

Why do authors derive new cardiovascular clinical prediction rules in the presence of existing rules? A mixed methods study

Background

Researchers should examine existing evidence to determine the need for a new study. It is unknown whether developers evaluate existing evidence to justify new cardiovascular clinical prediction rules (CPRs).

Objective

We aimed to assess whether authors of cardiovascular CPRs cited existing CPRs, why some authors did not cite existing CPRs, and why they thought existing CPRs were insufficient.

Method

Derivation studies of cardiovascular CPRs from the International Register of Clinical Prediction Rules for Primary Care were evaluated. We reviewed the introduction sections to determine whether existing CPRs were cited. Using thematic content analysis, the stated reasons for determining existing cardiovascular CPRs insufficient were explored. Study authors were surveyed via e-mail and post. We asked whether they were aware of any existing cardiovascular CPRs at the time of derivation, how they searched for existing CPRs, and whether they thought it was important to cite existing CPRs.

Results

Of 85 derivation studies included, 48 (56.5%) cited existing CPRs, 33 (38.8%) did not cite any CPR, and four (4.7%) declared there was none to cite. Content analysis identified five categories of existing CPRs insufficiency related to: (1) derivation (5 studies; 11.4% of 44), (2) construct (31 studies; 70.5%), (3) performance (10 studies; 22.7%), (4) transferability (13 studies; 29.5%), and (5) evidence (8 studies; 18.2%). Authors of 54 derivation studies (71.1% of 76 authors contacted) responded to the survey. Twenty-five authors (46.3%) reported they were aware of existing CPR at the time of derivation. Twenty-nine authors (53.7%) declared they conducted a systematic search to identify existing CPRs. Most authors (90.7%) indicated citing existing CPRs was important.

Conclusion

Cardiovascular CPRs are often developed without citing existing CPRs although most authors agree it is important. Common justifications for new CPRs concerned construct, including choice of predictor variables or relevance of outcomes. Developers should clearly justify why new CPRs are needed with reference to existing CPRs to avoid unnecessary duplication.

Hospital Admissions for Chest Pain Associated with Cocaine Use in the United States

BACKGROUND

The outcomes related to chest pain associated with cocaine use and its burden on the healthcare system are not well studied.

METHODS

Data were collected from the Nationwide Inpatient Sample (2001-2012). Subjects were identified by using the International Classification of Diseases, Ninth Revision, Clinical Modification codes. Primary outcome was a composite of mortality, myocardial infarction, stroke, and cardiac arrest.

RESULTS

We identified 363,143 admissions for cocaine-induced chest pain. Mean age was 44.9 (±21.1) years with male predominance. Left heart catheterizations were performed in 6.7%, whereas the frequency of acute myocardial infarction and percutaneous coronary interventions were 0.69% and 0.22%, respectively. The in-hospital mortality was 0.09%, and the primary outcome occurred in 1.19% of patients. Statistically significant predictors of primary outcome included female sex (odds ratio [OR], 1.16; confidence interval [CI], 1.00-1.35; P = .046), age >50 years (OR, 1.24, CI, 1.07-1.43; P = .004), history of heart failure (OR, 1.63, CI, 1.37-1.93; P <.001), supraventricular tachycardia (OR, 2.94, CI, 1.34-6.42; P = .007), endocarditis (OR, 3.5, CI, 1.50-8.18, P = .004), tobacco use (OR, 1.3, CI, 1.13-1.49; P <.001), dyslipidemia (OR, 1.5, CI, 1.29-1.77; P <.001), coronary artery disease (OR, 2.37, CI, 2.03-2.76; P <.001), and renal failure (OR, 1.27, CI, 1.08-1.50; P = .005). The total annual projected economic burden ranged from $155 to $226 million with a cumulative accruement of more than $2 billion over a decade.

CONCLUSION

Hospital admissions due to chest pain and concomitant cocaine use are associated with low rates of adverse outcomes. For the low-risk cohort in whom acute coronary syndrome has been ruled out, hospitalization may not be beneficial and may result in unnecessary cardiac procedures.

Diagnostic Yield of Routine Stress Testing in Low and Intermediate Risk Chest Pain Patients Under 40 Years: A Systematic Review

OBJECTIVE

Chest pain is one of the most frequent causes for presentation to emergency departments (EDs). The majority of patients will undergo diagnostic workup including stress testing to rule out an acute coronary syndrome, but very few patients will be diagnosed with a cardiac cause for their pain. Patients under 40 years represent a lower risk group in which routine stress testing may be of little benefit. This systematic review sought to determine the diagnostic yield of routine stress testing in low- and intermediate-risk chest pain patients under 40 years.

METHODS

Electronic databases were searched for relevant studies. The quality of the included primary studies was assessed using the National Health and Medical Research Council evidence hierarchy and the McMaster Critical Appraisal Tool for Quantitative Studies. Descriptive statistics summarized the findings.

RESULTS

Five primary studies were included in the review (all level III-3 evidence); 7 additional sources of relevant data were also included. Diagnostic yield of routine stress testing in low- and intermediate-risk patients under 40 years is reported between 0% and 1.1%. Combined data from included primary studies demonstrated just 4 out of 1683 true positive stress tests (0.24%), only one of which was definitively confirmed by coronary angiogram; additional data sources identified just 1 out of 310 true positive stress tests (0.32%).

CONCLUSIONS

Diagnostic yield of routine stress testing in low- and intermediate-risk chest pain patients under 40 years is low. However, better quality studies are required to be able to draw definitive conclusions.

Avoidable utilization of the chest pain observation unit: evaluation of very-low-risk patients

BACKGROUND

Very-low-risk patients treated in a chest pain observation unit (CPOU) may threaten efficient care delivery. To optimize the efficiency of CPOU evaluations, it is necessary to quantify the avoidable CPOU utilization rate, examine physician variability, and determine patient and physician characteristics associated with avoidable CPOU utilization.

METHODS

Consecutive chest pain patients were evaluated in an Emergency Department-based CPOU. Patients were risk stratified based on the American College of Cardiology/American Heart Association framework, age, and electrocardiogram findings. Very-low-risk was defined as age <35, physician assessment of low-risk, and normal or nondiagnostic electrocardiogram. Patients identified as very-low-risk were considered avoidable CPOU evaluations. Individual physicians' avoidable CPOU utilization rates were calculated. Patients were followed for 30-day major adverse cardiac events, defined as the composite of death, acute myocardial infarction, and coronary revascularization.

RESULTS

Over 33 months, the registry included 1731 chest pain patients. The study definition of avoidable CPOU evaluations was met by 174 patients (10.1%, 95% confidence interval: 8.7-11.6%). The median rate of physician's avoidable CPOU utilization was 10% (interquartile range: 5.9-13.6%) and varied from 1.9% to 18.4%. None of the patients with an avoidable CPOU evaluation had a major adverse cardiac events within 30 days. Physician predictors of avoidable CPOU utilization included recent residency graduation (<5 years), part-time status, and moderate or high rates of CPOU use.

CONCLUSIONS

Approximately 10% of CPOU evaluations were avoidable. Wide variability exists among physicians regarding their individual rates of avoidable CPOU utilization. This variability could represent an opportunity to improve the efficiency of CPOU care delivery.

HEART score to further risk stratify patients with low TIMI scores

OBJECTIVE

The ability to risk stratify patients presenting to the emergency department (ED) with potential acute coronary syndrome (ACS) is critical. The thrombolysis in myocardial infarction (TIMI) risk score can risk stratify ED patients with potential ACS but cannot identify patients safe for ED discharge. The symptom-based HEART score identifies very low-risk patients. Our hypothesis was that patients with a TIMI score of 0 or 1 may be stratified further with the HEART score to identify a group of patients at less than 1% risk of 30-day cardiovascular events.

METHODS

We conducted a secondary analysis of a prospective cohort study in a tertiary care hospital ED. Patients with potential ACS who were >30 years of age were included. Data collected included demographics, history, electrocardiogram, laboratories, and components of the TIMI and HEART scores. Follow-up was conducted by structured record review and phone. The main outcome was a composite of death, acute myocardial infarction, or revascularization at 30 days.

RESULTS

There were 8815 patients enrolled (mean age, 52.8 ± 15.1 years; 57% women, and 69% black). At 30 days, the composite event rate was 8.0% (660 patients): 108 deaths, 410 acute myocardial infarction, and 301 revascularizations. Of the 485 patients with both a TIMI score of 0 and a HEART score of 0, there were no cardiovascular events (95% confidence interval, 0-0.8%); but no other score combination had an upper limit confidence interval less than 1%.

CONCLUSION

At all levels of TIMI score, the HEART score was able to further substratify patients with respect to 30-day risk. A HEART score of 0 in a patient with a TIMI of 0 identified a group of patients at less than 1% risk for 30-day adverse events.

Validation of the Vancouver Chest Pain Rule: a prospective cohort study

OBJECTIVES

The objective was to validate the Vancouver Chest Pain Rule in an emergency department (ED) setting to identify very-low-risk patients with acute chest pain.

METHODS

A prospective cohort study was conducted on consecutive patients 25 years of age and older presenting to the ED with a chief complaint of acute chest pain during January 2009 to July 2009. According to the Vancouver Chest Pain Rule, cardiac history, chest pain characteristics, physical and electrocardiogram (ECG) findings, and cardiac biomarker measurement (creatine kinase-myocardial band isoenzyme [CK-MB]) were used to identify patients with very low risk for developing acute coronary syndrome (ACS) in 30 days. The primary outcome was defined as developing ACS (myocardial infarction or non-ST-elevation myocardial infarction [MI]/unstable angina) within 30 days of ED presentation, and all diagnoses were made using predefined explicit criteria. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated.

RESULTS

Of 593 patients who were eligible for evaluation, 39 (6.6%) developed MI and 43 (7.3%) developed unstable angina. Among all patients, 292 (49.2%) patients could have been assigned to the very-low-risk group and discharged after a brief ED assessment according to the Vancouver Chest Pain Rule. Among these patients, four (1.4%) developed ACS within 30 days. Sensitivity of the rule was 95.1% (95% confidence interval [CI]=88.0% to 98.7%), specificity was 56.3% (95% CI=52.0% to 60.7%), positive prediction value was 25.9% (95% CI=21.0% to 31.0%), and negative prediction value was 98.6% (95% CI=96.5% to 99.6%).

CONCLUSIONS

This study showed a lower sensitivity and higher specificity when applying the Vancouver Chest Pain Rule to this population as compared to the original study.

[Chest pains in emergency admission. Diagnostics and treatment]

Thoracic pain is a common symptom in the emergency medicine setting and represents a diagnostic and therapeutic challenge. A multitude of differential diagnoses must be considered many of which are associated with a high mortality. Management of this situation is complicated by the fact that rapid and unexpectedly occurring and rapidly progressing deterioration are not uncommon in patients who initially did not appear to be seriously ill. Also for some underlying pathologies the physical examination can have an inconspicuous or"false negative" result and atypical presentations can give rise to false interpretations. The clinical and technical diagnostic methods, the implementation and interpretation including possible sources of error and limitations will be described in detail.

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

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

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

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

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.

A young soldier with syncope, shortness of breath and palpitations

Introduction. Coronary artery disease in people under 30 years is relatively uncommon, but once a disease occurs it brings a significant morbidity and psychological effects. Case report. We reported a 28-year-old patient presenting atypical symptoms after sincopa and non-specific changes on electrocardiogram at admission. After noninvasive and invasive cardiology diagnostic procedures were made, we concluded that he had a subtotal tubular stenosis in proximal segment of the left anterior descending coronary artery. Myocardial revascularization was successfully performed 24-hour after coronarography with the left internal mammary thoracic artery graft on the left anterior descending coronary artery and the patient had a prompt and satisfactory postoperative recovery. Conclusion. This case indicates the importance of a careful evaluation of young adults even if they do not experience typical anginal symptoms or do not have multiple risk factors for cardiovascular diseases.

A study to derive a clinical decision rule for triage of emergency department patients with chest pain: design and methodology

BACKGROUND

Chest pain is the second most common chief complaint in North American emergency departments. Data from the U.S. suggest that 2.1% of patients with acute myocardial infarction and 2.3% of patients with unstable angina are misdiagnosed, with slightly higher rates reported in a recent Canadian study (4.6% and 6.4%, respectively). Information obtained from the history, 12-lead ECG, and a single set of cardiac enzymes is unable to identify patients who are safe for early discharge with sufficient sensitivity. The 2007 ACC/AHA guidelines for UA/NSTEMI do not identify patients at low risk for adverse cardiac events who can be safely discharged without provocative testing. As a result large numbers of low risk patients are triaged to chest pain observation units and undergo provocative testing, at significant cost to the healthcare system. Clinical decision rules use clinical findings (history, physical exam, test results) to suggest a diagnostic or therapeutic course of action. Currently no methodologically robust clinical decision rule identifies patients safe for early discharge.

METHODS/DESIGN

The goal of this study is to derive a clinical decision rule which will allow emergency physicians to accurately identify patients with chest pain who are safe for early discharge. The study will utilize a prospective cohort design. Standardized clinical variables will be collected on all patients at least 25 years of age complaining of chest pain prior to provocative testing. Variables strongly associated with the composite outcome acute myocardial infarction, revascularization, or death will be further analyzed with multivariable analysis to derive the clinical rule. Specific aims are to: i) apply standardized clinical assessments to patients with chest pain, incorporating results of early cardiac testing; ii) determine the inter-observer reliability of the clinical information; iii) determine the statistical association between the clinical findings and the composite outcome; and iv) use multivariable analysis to derive a highly sensitive clinical decision rule to guide triage decisions.

DISCUSSION

The study will derive a highly sensitive clinical decision rule to identify low risk patients safe for early discharge. This will improve patient care, lower healthcare costs, and enhance flow in our busy and overcrowded emergency departments.

The role of cardiac risk factor burden in diagnosing acute coronary syndromes in the emergency department setting

STUDY OBJECTIVE

We seek to determine whether cardiac risk factor burden (defined as the number of conventional cardiac risk factors present) is useful for the diagnosis of acute coronary syndromes in the emergency department (ED) setting.

METHODS

This was a post hoc analysis of the Internet Tracking Registry of Acute Coronary Syndromes (i*trACS) registry, which had 17,713 ED visits for suspected acute coronary syndromes. First visit for US patients who were not cocaine or amphetamine users, who did not leave against medical advice, and for whom ECG and demographic data were complete were included. Acute coronary syndrome was defined by 30-day revascularization, diagnostic-related group codes, or death within 30 days, with positive cardiac biomarkers at index hospitalization. Cardiac risk factors were diabetes, hypertension, smoking, hypercholesterolemia, and family history of coronary artery disease. Cardiac risk factor burden was defined as the number of risk factors present. Because multiple logistic regression analysis revealed that age modified the relationship between cardiac risk factor burden and acute coronary syndromes, a stratified analysis was performed for 3 age categories: younger than 40, 40 to 65, and older than 65 years. Positive likelihood ratios and negative likelihood ratios with their 95% confidence intervals (CIs) were calculated for each total risk factor cutoff.

RESULTS

Of 10,806 eligible patients, 871 (8.1%) had acute coronary syndromes. In patients younger than 40 years, having no risk factors had a negative likelihood ratio of 0.17 (95% CI 0.04 to 0.66), and having 4 or more risk factors had a positive likelihood ratio of 7.39 (95% CI 3.09 to 17.67). In patients between 40 and 65 years of age, having no risk factors had a negative likelihood ratio of 0.53 (95% CI 0.40 to 0.71), and having 4 or more risk factors had a positive likelihood ratio of 2.13 (95% CI 1.66 to 2.73). In patients older than 65 years, having no risk factors had a negative likelihood ratio of 0.96 (95% CI 0.74 to 1.23), and having 4 or more risk factors had a positive likelihood ratio of 1.09 (95% CI 0.64 to 1.62).

CONCLUSION

Cardiac risk factor burden has limited clinical value in diagnosing acute coronary syndromes in the ED setting, especially in patients older than 40 years.

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.

Prediction of missed myocardial infarction among symptomatic outpatients without coronary heart disease

BACKGROUND

Missed diagnoses of acute myocardial infarction (AMI) in the ambulatory setting can cause patient suffering and malpractice litigation. Multiple algorithms have been developed to detect the presence of coronary heart disease (CHD) or acute coronary ischemia.

METHODS

We performed a case-control study of patients with no prior history of CHD presenting to outpatient practices with potential cardiac ischemia. Malpractice claims files were used to identify 18 cases of patients with missed AMIs. For each case, we identified 3 control patients who had office visits for chest pain during the same month and assessed the association of 4 different prediction tools with missed AMI.

RESULTS

The 18 cases of missed AMI had a 39% 1-month mortality rate. Cases were more likely than controls to be men (67% vs 26%, P = .001), to be smokers (88% vs 39%, P < .001), and to have low HDL cholesterol (39 mg/dL vs 59 mg/dL, P < .001) and elevated total cholesterol (236 mg/dL vs 213 mg/dL, P = .01). A Framingham risk score predicting a 10-year risk of CHD > or =10% and a positive score using the Goldman risk predictor were associated with an increased risk of missed AMI (odds ratio 5.7, 95% CI 1.8-18.4 for Framingham risk score; odds ratio 7.2, 95% CI 1.4-36.8 for Goldman risk predictor).

CONCLUSIONS

Among ambulatory patients with possible cardiac ischemia and no prior CHD, multiple algorithms may be useful for improvement of risk stratification.

Risk factors for premature coronary artery disease and determinants of adverse outcomes after revascularization in patients < or =40 years old

Smoking is an important and modifiable risk factor associated with premature atherosclerosis and the need for coronary revascularization in young adult patients < or =40 years old. Although intermediate and long-term survival is better in young adult patients after percutaneous coronary intervention, co-morbidities such as low ejection fraction, previous myocardial infarction, and previous bypass surgery are important adverse prognostic determinants.

Validation of a brief observation period for patients with cocaine-associated chest pain

BACKGROUND

Retrospective studies of patients with cocaine-associated chest pain suggest that a strategy of discharging patients from the emergency department after a 12-hour observation period if they do not have evidence of ischemia should be associated with a very low rate of complications.

METHODS

We prospectively evaluated the safety of a 9-to-12-hour observation period in patients with cocaine-associated chest pain who were at low-to-intermediate risk of cardiovascular events. Consecutive patients who reported or tested positive for cocaine use and who received protocol-driven care in a chest-pain observation unit were included. Patients who had normal levels of troponin I, without new ischemic changes on electrocardiography, and who had no cardiovascular complications (dysrhythmias, acute myocardial infarction, or recurrent symptoms) during the 9-to-12-hour observation period were discharged from the unit. The main outcome was death from cardiovascular causes at 30 days.

RESULTS

Three hundred forty-four patients with cocaine-associated chest pain were evaluated. Forty-two of these patients (12 percent) were directly admitted to the hospital. The study cohort comprised the remaining 302 patients. During the 30-day follow-up period, none of the patients died of a cardiovascular event (0 percent; 95 percent confidence interval, 0 to 0.99), and only 4 of the 256 patients for whom detailed follow-up data were available had a nonfatal myocardial infarction (1.6 percent; 95 percent confidence interval, 0.1 to 3.1). All four nonfatal myocardial infarctions occurred in patients who continued to use cocaine.

CONCLUSIONS

Patients with cocaine-associated chest pain who do not have evidence of ischemia or cardiovascular complications over a 9-to-12-hour period in a chest-pain observation unit have a very low risk of death or myocardial infarction during the 30 days after discharge.