A chest pain clinic to improve the follow-up of patients released from an urban university teaching hospital emergency department

During a 12-month period, 1,045 of 1,554 patients (67%) over age 30 seen in an urban teaching hospital emergency department with acute chest pain were released based on the clinical judgment of the examining physician. Patients who were released were offered follow-up within 24 to 72 hours in a hospital-based chest pain clinic. Of these 1,045 patients, 772 (74%) returned or were contacted by phone, and 29 were directly admitted; 14 had unstable angina, and eight had new myocardial infarctions. Because of its positive impact on the quality of care at an acceptable cost, the Chest Pain Clinic, which was originally instituted as part of a research protocol, has now become part of the routine spectrum of care provided at the University of Cincinnati Medical Center.     

Identification of patients at risk by graded exercise testing in an emergency department chest pain center

The study applied a retrospective follow-up design to determine the prognostic effect of graded exercise testing (GXT) in patients with low- to moderate-risk chest pain evaluated in an emergency department 9-hour protocol chest pain center (CPC) from January 1, 1993 to August 1, 1996. The cohort of 1,209 patients were followed to the date of death or first adverse cardiac event up to 1 year after CPC admission. Cardiac events were defined as coronary artery bypass graft, percutaneous transluminal coronary angioplasty, cardiogenic shock, cardiac-related death, congestive heart failure admission, ventricular tachycardia/ventricular fibrillation arrest, and myocardial infarction. Patients with acute ST-segment elevation or depression of >1 mm, positive enzyme (creatine kinase myocardial band) testing, or unstable angina during their CPC evaluation were admitted without GXT testing. Statistical analysis included chi-square test for complication rates and Cox proportional-hazards modeling. Nine hundred fifty-eight of 1,209 patients underwent GXT testing. Patients with positive, inconclusive, and normal GXTs had complication rates of 36.8% (7 of 19), 3.4% (9 of 267), and 1.1% (5 of 456), respectively. After adjusting for age, sex, and race, the relative risk of complication was 38.9 (95% confidence interval 11.7 to 129.6) with a positive GXT, and 3.6 (95% confidence interval 1.2 to 10.7) with an inconclusive GXT compared with a normal GXT. The GXT is a good prognostic indicator of adverse cardiac events in low- to moderate-risk chest pain in patients evaluated in an emergency department CPC.     

在急诊科设立胸痛中心对胸痛患者诊疗时间的影响

目的在急诊科设立胸痛中心并研究其对急性胸痛患者诊疗时间的影响。方法在急诊科设立急性胸痛中心,每周开诊3d,时间随机确定,其余时间由急诊科按常规流程对胸痛患者进行诊疗,由研究者对急性胸痛患者的病因和诊疗时间进行注册登记。结果2006年1月至2007年12月因急性非创伤性胸痛就诊北京军区总医院急诊科或胸痛中心的患者共696例,心源性胸痛244例（35％）,包括急性心肌梗死141例（20％）,不稳定型心绞痛81例（12％）,稳定型心绞痛17例（2．4％）,主动脉夹层2例（0．3％）,急性肺栓塞3例（0．4％）;非心源性胸痛452例（65％）,呼吸系统41例（6％）,消化系统70例（10％）,胸膜骨骼肌肉41例（6％）,神经精神或其他299例（42％）。经胸痛中心诊治的胸痛患者的诊疗时间与常规诊疗流程相比都有所缩短。急性心肌梗死（70．1±31．7）min vs（115±40．5）min（P〈0．01）;不稳定型心绞痛（228±54）min vs（264±78）min（P=0．02）;非心源性胸痛（108±66）min vs （126±96）min（P=0．03）。结论急性胸痛患者的病因中,心源性者占35％,以急性心肌梗死和不稳定型心绞痛为主;非心源性者占65％。胸痛中心模式能显著缩短急性胸痛患者的诊疗时间。     

Prognosis of negative adenosine stress magnetic resonance in patients presenting to an emergency department with chest pain.

OBJECTIVES: This study was designed to determine the diagnostic value of adenosine cardiac magnetic resonance (CMR) in troponin-negative patients with chest pain. BACKGROUND: We hypothesized that adenosine CMR could determine which troponin-negative patients with chest pain in an emergency department have coronary artery disease (CAD) or future adverse cardiac events. METHODS: Adenosine stress CMR was performed on 135 patients who presented to the emergency department with chest pain and had acute myocardial infarction (MI) excluded by troponin-I. The main study outcome was detecting any evidence of significant CAD. Patients were contacted at one year to determine the incidence of significant CAD defined as coronary artery stenosis >50% on angiography, abnormal correlative stress test, new MI, or death. RESULTS: Adenosine perfusion abnormalities had 100% sensitivity and 93% specificity as the single most accurate component of the CMR examination. Both cardiac risk factors and CMR were significant in Kaplan-Meier analysis (log-rank test, p = 0.0006 and p < 0.0001, respectively). However, an abnormal CMR added significant prognostic value in predicting future diagnosis of CAD, MI, or death over clinical risk factors. In receiver operator curve analysis, adenosine CMR was a more accurate predictor than cardiac risk factors (p < 0.002). CONCLUSIONS: In patients with chest pain who had MI excluded by troponin-I and non-diagnostic electrocardiograms, an adenosine CMR examination predicted with high sensitivity and specificity which patients had significant CAD during one-year follow-up. Furthermore, no patients with a normal adenosine CMR study had a subsequent diagnosis of CAD or an adverse outcome.     

Prospective evaluation of an EDB-based diagnostic program to be used in patients admitted to hospital with acute chest pain

A recently designed computer based decision support system (DSP),almost exclusively based on case history data, was developedto facilitate immediate differentiation between patients withand without urgent need for coronary care unit (CCU) transferralfrom the emergency room, and additionally to distinguish betweenpatients with and without acute myocardial infarction (MI). One-year's prospective testing in a consecutive series of 1252patients with acute chest pain revealed that the DSP, used inaddition to ECG and clinical examination, demonstrated a sensitivityof 96% in the detection of patients in need of CCU observation(MI-sensitivity of 98%), and a specificity of 56% in excludingpatients who were not in need of CCU observation. The proportionof referrals to the CCU judged to be unnecessary was only 17%of the total number of patients seen in the emergency room.     

The referral of patients from freestanding emergency centers to a hospital emergency department

This retrospective study is a review of patients referred from a network of eight freestanding emergency centers FECs to a hospital emergency department during January and February 1984. During that time, 17,387 patients were seen at the FECs. Sixty-three (0.36%) of these patients were referred to the base hospital, of which 28 (44%) were admitted and six (9.5%) were admitted to a critical care unit. Four of the six critical care admissions arrived by ambulance. One was unstable and required cardioversion in the ED. Of the patients discharged from the hospital 70% were satisfied with FEC and 97% with hospital treatment. Of admitted patients, 89% were satisfied with FEC and 100% were satisfied with hospital treatment. For a similar illness in the future, 23% of all patients would return to a FEC, 28% would go to a private practitioner, and 48% would go directly to a hospital.     

The causes of musculoskeletal chest pain in patients admitted to hospital with suspected myocardial infarction

BACKGROUND: We wished to investigate the causes and characteristics of musculoskeletal chest pain leading to acute medical admission. METHODS: We studied patients admitted to Queen Elizabeth Hospital, Gateshead, over a 10-week period. Patients with chest pain for which no acute cardiorespiratory cause was evident were identified and only included if they were tender on anteroposterior chest compression, thoracic spine rotation or firm sternal pressure. A detailed clinical history, anxiety and depression scale and a focussed physical examination were done to define the nature of musculoskeletal disease and their therapeutic requirements. RESULTS: Fifty patients satisfying the inclusion criteria were admitted in the 10-week period and comprised 54% females with a mean age of 57 years (S.D.=13.48). Chest pain lasted for 1 h or less in 24 patients and was mostly anterior. Three distinct groups of patients were identified. Twelve patients had evidence of inflammatory joint disease, thirteen had fibromyalgia and half had regional syndromes with pain arising from the shoulder, neck, thoracic spine or sternocostal areas. Visual analogue scores were highest in fibromyalgia for pain, and highest in inflammatory arthritis for impaired mobility. Anxiety and depression scores were highest in fibromyalgia and lowest among patients with regional syndromes. CONCLUSIONS: Musculoskeletal causes for acute chest pain are common and varied. Most patients have an identifiable cause of pain, but accurate diagnosis is needed to select the most appropriate intervention. Anxiety and depression are frequent, with much self-reported pain and dysfunction. However, all patients in this study had a disorder that was amenable to treatment and diagnosis. Management needs to be actively pursued in all patients.     

Hypomagnesemia is a frequent finding in the emergency department in patients with chest pain

STUDY OBJECTIVE--To evaluate the frequency of low blood levels of total and ultrafilterable magnesium (total and ultrafilterable hypomagnesemia) in patients with chest pain in the emergency department, and to determine if hypomagnesemia is associated with other clinically important diagnostic and outcome variables in cardiac care. SETTING--An emergency department of a university teaching hospital. DESIGN--Prospective study of extracellular magnesium homeostasis in patients with chest pain in the emergency department and a cohort of patients without chest pain with a clinical indication for blood sampling. PATIENTS--During a 4-month period, 147 patients presenting to the emergency department were studied: 67 patients (mean +/- SD age, 61.4 +/- 13 years) with a chief complaint of chest pain (study group) and 80 patients (55.6 +/- 19 years) with other diagnoses (control group). RESULTS--Total and ultrafilterable hypomagnesemia occurred more frequently in patients with chest pain (20/67 [30%] and 9/67 [13%]) than in the control group (12/80 [15%] and 3/80 [4%]). Patients with a chief complaint of chest pain who were receiving diuretic medications were hypomagnesemic more frequently (9/16 [56%]) than patients not receiving diuretics (12/51 [23%]). In patients with chest pain admitted to the hospital with a diagnosis of "rule out" myocardial infarction, the frequency of hypokalemia was greater among hypomagnesemic patients (6/14 [43%]) than normomagnesemic patients (3/31 [10%]). A similar frequency of hypomagnesemia was noted in patients with a final diagnosis of myocardial infarction (4/15 [27%]) when compared with other patients admitted with chest pain (10/31 [32%]) in whom myocardial infarction was excluded. No association was noted among hypomagnesemia and length of hospital stay or the occurrence of hypotension or dysrhythmias. CONCLUSIONS--Total and ultrafilterable hypomagnesemia are frequent occurrences in patients with and without chest pain in the emergency department. Diuretic use is associated with hypomagnesemia in patients presenting with chest pain in the emergency department. These results support the concept that hypomagnesemia is common in patients with chest pain in the emergency department and is associated with hypokalemia but is not predictive of whether the patient with chest pain has had an acute myocardial infarction.     

Initial presenting electrocardiogram as determinant for hospital admission in patients presenting to the emergency department with chest pain: a pilot investigation

BACKGROUND: Evaluation of chest pain accounts for millions of costly Emergency Department (ED) visits and hospital admissions annually. Of these, approximately 10-20% are myocardial infarctions (MI). HYPOTHESIS: Patients with chest pain whose initial electrocardiogram (ECG) is normal do not require hospital admission for evaluation and management of a possible myocardial infarction. METHODS: The medical records of a consecutive cohort of 250 patients who presented to the ED with chest pain and were admitted by the ED physician to a cardiology inpatient service of an academic tertiary care medical center were reviewed. Reasons for admission to hospital was to rule out an acute coronary syndrome, specifically, myocardial infarction. The initial ECG of each patient was evaluated for abnormalities and compared with the final diagnosis. RESULTS: Of the 75 patients presenting with normal ECGs (normal, upright T waves and isoelectric ST segments), 1 (1.3%) was subsequently diagnosed with a myocardial infarction by Troponin I elevation alone. Of the 55 patients presenting with abnormal ECGs but no clear evidence of ischemia [i.e., left bundle branch block (LBBB), right bundle branch block (RBBB), left anterior hemiblock (LAH)], 2 (3.6%) were diagnosed with MI. Of the 48 patients presenting with abnormal ECGs questionable for ischemia (nonspecific ST and T wave changes that were not clearly ST segment elevation or depression), 7 (14.6%) were diagnosed with an MI. Of the 72 patients who presented with abnormal ECGs showing ischemia (acute ST segment elevation and/or depression), 39 (54.2%) were shown to have evidence for MI. SUMMARY: Patients who presented with normal ECGs (category 1) were extremely low risk for acute myocardial infarction. Patients with abnormal ECGs but no evidence of definite ischemia (category 2) had a relatively low incidence of MI. Patients with abnormal ECGs questionable for ischemia (category 3) had an intermediate risk of acute myocardial infarction. The majority of patients with abnormal ECGs demonstrating ischemia (category 4) were subsequently shown to evolve an acute myocardial infarction. CONCLUSIONS: Patients with chest pain and initial ECGs with ST segment abnormalities suggestive or diagnostic for ischemia, should be admitted to the hospital for further evaluation and management. Patients with ECGs that do not display acute ST segment changes are at a lower risk for acute myocardial infarction than those with acute ST segment changes and should be admitted on the basis of cardiac risk profile. (i.e., age, gender, hypertension, diabetes, smoking, known coronary artery disease, etc.) Patients with normal ECGs (category 1) are at extremely low risk, and it may be acceptable to consider further evaluation on an outpatient basis.     

Counterregulatory hormones in insulin-treated diabetic patients admitted to an accident and emergency department with hypoglycaemia

The aim of the study was (1) to describe hormone responses in insulin-induced hypoglycaemia and (2) to investigate if a combined treatment with intravenous glucose and intramuscular glucagon (group A) would improve glucose recovery as compared to treatment with intravenous glucose alone (group B). Eighteen adult patients with insulin-treated diabetes mellitus admitted to the Accident and Emergency Department with hypoglycaemia (plasma glucose 1.23 ± 0.15 mmol l⁻¹ on admission) were randomized to one of the above treatments and plasma glucose and counterregulatory hormones were measured before and 30–120 min after treatment. Pre-treatment counterregulatory hormone concentrations were significantly lower than hormone concentrations during induced hypoglycaemia in healthy control subjects but significantly higher than healthy fasting concentrations for plasma adrenaline (p = 0.020), glucagon (p = 0.008), growth hormone (p = 0.011), and cortisol (p<0.00001). Thus, although glucagon and adrenaline responses may be absent when studying Type 1 diabetic patients in the experimental setting, both hormones increase to a significant extent in ‘real-life’ hypoglycaemia in this patient group, although to a lesser degree than might be expected. Plasma glucose did not differ significantly between the two treatments at any time point. Despite access to food, one of four patients in group B and one of five patients in group A had plasma glucose below 4.0 mmol l⁻¹ after 120 min. In conclusion, low yet significantly elevated concentrations of adrenaline and glucagon were found in diabetic patients admitted with severe hypoglycaemia to an Accident and Emergency Department. © 1998 John Wiley & Sons, Ltd.     

Chest pain units: a modern way of managing patients with chest pain in the emergency department

It is estimated that 5 to 8 million individuals with chest pain or other symptoms suggestive of myocardial ischemia are seen each year in emergency departments (ED) in the United States 1,2, which corresponds to 5 to 10% of all visits 3,4. Most of these patients are hospitalized for evaluation of possible acute coronary syndrome (ACS). This generates an estimated cost of 3 - 6 thousand dollars per patient 5,6. From this evaluation process, about 1.2 million patients receive the diagnosis of acute myocardial infarction (AMI), and just about the same number have unstable angina. Therefore, about one half to two thirds of these patients with chest pain do not have a cardiac cause for their symptoms 2,3. Thus, the emergency physician is faced with the difficult challenge of identifying those with ACS - a life-threatening disease - to treat them properly, and to discharge the others to suitable outpatient investigation and management.     

Physician response to a prediction rule for the triage of emergency department patients with chest pain

Objective: To determine the response of physicians to a noncoercive prediction rule for the triage of emergency department patients with chest pain. Design: Prospective time-series intervention study. Setting: A university hospital emergency department. Participants/patients: 68 physicians, all of whom were responsible for the triage of at least one of 252 patients presenting to the emergency department with a chief complaint of acute chest pain. Intervention: A previously validated algorithmic prediction rule that was attached to the back of patient data forms in the emergency department. Measurements: Patients’ clinical data were recorded by the examining physician in the emergency department or by a research nurse blinded to patient outcome. The physicians recorded their own estimates of the risk of acute myocardial infarction and their reactions to the prediction rule in a self-administered questionnaire completed at the time of triage. Main results and conclusions: The physicians reported that they looked at the prediction rule during the triage of 115 (46%) of the 252 patients. The likelihood of using the prediction rule decreased significantly with increasing level of physician training. The most common reasons given for disregarding the prediction rule were confidence in unaided decision making and lack of time. The physicians reported that of the 115 cases for which the prediction rule was used, only one triage decision (1% ) was changed by it. Future research should explore how prediction rules can be designed and implemented to surmount the barriers highlighted by these data. Received from the Section for Clinical Epidemiology, the Division of General Medicine, the Cardiovascular Division, Department of Medicine, the Department of Emergency Medicine, and the Clinical Initiatives Development Program, Brigham and Women’s Hospital and Harvard Medical School, and the Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts. Dr. Lee is a recipient of an Established Investigator Award (900119) from the American Heart Association. Supported by a grant from the Agency for Health Care Policy and Research (5R01-HS0452).