Multicenter Study of Creatine Kinase-MB Use: Effect on Chest Pain Clinical Decision Making

Objective: To determine whether creatine kinase-MB isomer (CK-MB) levels affect initial physician decisions regarding patients with potential cardiac chest pain.
Methods: A prospective, multicenter, observational cohort study was performed at seven university teaching hospital EDs. Hemodynamically stable chest pain patients >25 years old and without ST-segment elevation on their ECGs were observed with one to two sets of CK-MB level determinations obtained three hours apart prior to disposition. The physicians committed to a dichotomous (yes/no) absolute decision regarding the diagnosis of myocardial infarction (MI), need for hospital admission, and need for coronary care unit (CCU) admission both before and after enzyme results were obtained. The physicians ranked the perceived importance of initial history and physical, serial clinical observation, initial ECG, and CK-MB level to their decision making (rank score: 1 = most important, 4 = least important).
Results: Of the 1,042 patients enrolled, 777 (74.6%) were admitted to the hospital. For the 67 MI patients (8.6% of the admissions), changes in absolute decisions about the diagnosis of MI and planned CCU admission were associated with increased CK-MB importance (p = 0.04 and p = 0.02, respectively). Of the 146 patients who had new-onset angina or unstable angina, changes in absolute decisions were not associated with CK-MB importance. No patient who had MI or unstable angina was released from the ED. There were three of 67 (4%) MI patients and one of 146 (1%) unstable/new-onset angina patients initially slated for release home who were admitted to the hospital.
Conclusions: For a minority of the patients who had subsequently proven MI, the CK-MB result helped guide disposition decisions. The CK-MB availability did not adversely impact the disposition of the patients who had unstable or new-onset angina.     

Follow-up of elderly patients who refuse transport after accessing 9-1-1

Objective. To obtain medical follow-up and determine reasons why elderly patients access paramedics via 9-1-1 and then refuse transport. Methods. A telephone survey of patients aged 65 years and older who refused transport and signed out against medical advice (AMA) after accessing paramedics via 9-1-1 was performed to obtain information about the patients' experiences, reasons why they refused, medical follow-up, and patient outcomes. Results. One hundred of 121 (83%) patients who were contacted by telephone participated in the survey. Patients stated that financial concerns were a major determinant in refusing to be transported. Overall, 70% of the patients reported receiving follow-up medical care. Care was obtained at an emergency department (ED) via a second 9-1-1 call in 16% of cases, at an ED via private vehicle in 13%, at an urgent care clinic by a private vehicle in 35%, and with a family physician via private car in 38% of cases. Of the patients who obtained follow-up, there was a 32% hospital admission rate, with 39% of those admitted to an intensive care unit setting. Finally, 80% of the sample studied did not speak to a physician online, with 49% stating that they would have changed their minds if a physician had suggested transport. Conclusion. The majority of patients who were 65 years of age and older and refused transport received follow-up care, with a significant number requiring admission to the hospital at the time of their follow-up. PREHOSPITAL EMERGENCY CARE 2002;6:391-395     

A preliminary epidemiological study of the patient population visiting an urban ED in the Republic of China

The objective of this study was to evaluate the characteristics of the patient population of an urban emergency department (ED) in The People's Republic of China. A prospective observational study was conducted at a university-affiliated hospital adult ED medical unit and included all patients visiting the medical unit of the ED during a 2-week period. A data collection log was designed and placed in the ED. Data were recorded by the attending ED physician for all patients presenting during the study period. There were 569 patients recorded in the 2-week period. The major presenting complaints were fever (20.9%), abdominal pain (20.1%), and chest pain (11.4%). The most common diagnoses were upper respiratory tract infection (11.6%), angina pectoris (6.3%), and acute gastritis (4.9%). Elght percent of the patients were admitted, 29.0% were held in an observation unit, and 0.6% died. The average length of stay in the ED observation unit was 5.6 days. These data offer emergency physicians a preliminary understanding of the clinic presentations and diagnoses of patients seen in a university-affiliated urban hospital ED in China. The number and length of time patients were held in observation unit point out the shortage of in-hospital beds. This study is useful for describing and understanding characteristics of the patient encounter and for improving the delivery of emergency care in China.     

Impact of a chest pain clinic on recurrency of symptoms and readmissions among patients early discharged from hospital after acute myocardial infarction was ruled out.

This paper evaluates the impact of an early revisit including symptom evaluation and an exercise electrocardiogram on recurrency of symptoms and readmissions during 1 year of follow-up among patients coming to hospital with chest pain or an initial suspicion of acute myocardial infarction (AMI) but in whom the suspicion was quickly ruled out. Patients below the age of 65 admitted to the emergency department (ED) at Sahlgrenska Hospital due to chest pain or other symptoms raising a suspicion of AMI who were either directly discharged from the ED or discharged within 1 day after having AMI ruled out. Patients were allocated to two groups: (1) patients being re-evaluated in a chest pain clinic less than a week after discharge from hospital (intervention group) and (2) patients handled routinely with no formalized follow-up (control group). The intervention group (n=484) and the control group (n=374) were comparable at baseline. During 1 year of follow-up, patients in the intervention group had a lower rate of readmissions to the ED than patients in the control group (17.4% versus 24.9%, p < 0.05) and a lower rate of rehospitalizations (15.9% versus 23.3%, p < 0.05). The proportion of patients being on sick leave at any time during the follow-up did not differ and neither did the recurrency of symptoms. The introduction of a chest pain clinic for patients early discharged from hospital after having AMI ruled out indicated beneficiency in terms of a lower rate of readmissions to the ED and a lower requirement of rehospitalizations. However, a methodological weakness in the randomization procedure suggest carefulness in interpretation.     

Effectiveness of an Organized Follow-up System for Elder Patients Released from the Emergency Department

Objectives : To determine whether an effective telephone callback system can be successfully implemented in a busy ED and to quantify the benefits that can be obtained related to the follow-up care of elder patients.
Methods : This was a prospective, cohort study conducted at a community teaching hospital during a 6-month period. Consecutive patients ≥60 years old and released from the ED were selected for telephone follow-up. Calls were made by a research nurse within 72 hours after the patient's ED visit. Follow-up information included current medical status, problems encountered during the ED visit, compliance, and impact of the illness on self-care capabilities.
Results : Seventy-nine percent (831/1,048) of the patients selected for telephone follow-up were successfully contacted. The calls lasted an average of 4 ± 2.5 minutes. Although 94% (778/831) of these patients had a regular physician, 14% failed to make their recommended follow-up arrangements. Compliance was significantly improved when a follow-up physician was contacted during the patient's ED visit. Approximately 96% of the patients were either satisfied or very satisfied with their ED care. However, 13% (109/831) had moderate deterioration in their ability to care for themselves. Of the patients contacted, 333 (40%) required further clarification of their home care instructions, 31 were advised to return to the ED for reevaluation, and 26 were referred to a medical social worker for psychosocial concerns.
Conclusion : A telephone callback system is a feasible and effective method to improve follow-up care of elder patients released from the ED.     

Uncompleted Emergency Department Care: Patients Who Leave against Medical Advice

Objectives: To compare the patient characteristics, clinical conditions, and short-term recidivism rates of emergency department (ED) patients who leave against medical advice (AMA) with those who leave without being seen (LWBS) or complete their ED care.
Methods: All eligible patients who visited the ED between July 1, 2004, and June 30, 2005 ( N = 31,252) were classified into one of four groups: 1) AMA ( n = 857), 2) LWBS ( n = 2,767), 3) admitted ( n = 8,894), or 4) discharged ( n = 18,734). The patient characteristics, primary diagnosis, and 30-day rates of emergent hospitalizations, nonemergent hospitalizations, and ED discharge visits were compared between patients who left AMA and each of the other study groups. A Cox proportional hazards model was used to examine the influence of study group status on the risk of emergent hospitalization, adjusted for patient characteristics.
Results: Patients who left AMA were significantly more likely to be uninsured or covered by Medicaid compared with those admitted or discharged (p < 0.001). The AMA visit rates were highest for nausea and vomiting (9.7%), abdominal pain (7.9%), and nonspecific chest pain (7.6%). During the 30-day follow-up period, patients who left AMA had significantly higher emergent hospitalization and ED discharge visit rates compared with each of the other study groups (p < 0.001). Insurance status, male gender, and higher acuity level were also associated with a significantly higher emergent hospitalization rate.
Conclusions: Patients who leave AMA may do so prematurely, as evidenced by higher emergent hospitalization rates compared with those who LWBS or complete their care.     

Impact of an emergency department pain management protocol on the pattern of visits by patients with sickle cell disease

This study explores how implementation of pain management guidelines in concert with clinic case management affected emergency department (ED) utilization, clinic visits, and hospital admissions for patients with sickle cell disease. A pain management guideline that eliminated meperidine and encouraged timely use of morphine or hydromorphone for pain control in sickle cell crisis was introduced as a quality improvement project. This study is a retrospective review of ED visits, clinic visits, and admissions from 1 year before and 3 years after the guideline implementation. Working with the ED, the Hematology Clinic began to proactively seek the return of their patients for clinic follow-up. A formal case management program for sickle cell patients was initiated in June 2003. A total of 1584 visits by 223 patients were collected, 1097 to the ED and 487 to the Hematology Clinic. Total hospital visits did not change significantly in any of the 4 years, p > 0.10 for each comparison. Total ED visits decreased significantly over the 4-year study period (p < 0.001), whereas clinic visits steadily increased (p < 0.001). Return visits to the ED within 30 days also declined significantly, p < 0.001. Both the absolute number of admissions per year and the total admissions per hospital visit per year declined significantly over the study period, p = 0.001. Although total admissions per hospital visit did not change, the proportion of ED visits that resulted in admission in year 1 (29%) was significantly lower than the proportion admitted in year 2 (43%), p = 0.04. A pain protocol using morphine or hydromorphone coupled with increased access to outpatient clinics decreased ED visits, hospitalizations, and increased utilization of a more stable primary care clinic setting by patients with sickle cell disease.     

Variance Cardiography for Emergency Department Evaluation of Chest Pain Patients

Objective: To determine the test performance of 24–lead variance cardiography (VC), an ECG technique that measures QRS morphologic variability, for ED evaluation of chest pain associated with coronary artery disease (CAD).
Methods: A prospective, single–blind study of VC was performed in a community teaching hospital ED. All chest pain patients (>30 years of age) who, after initial emergency physician evaluation, were believed to have pain of potential cardiac etiology and were admitted to the hospital were eligible. Exclusion criteria included obvious noncardiac etiology for discomfort, bundle–branch block, atrial fibrillation, and incomplete subsequent cardiac evaluation. After initial evaluation and stabilization, VC was obtained. The numerical output of VC was a CAD index (CADI). Serum myoglobin and creatine kinase (CK)–MB levels were obtained at the time of presentation and after one, two, and six hours. Hospital records were reviewed to determine final diagnosis and in–hospital evaluation results.
Results: Fifty–two of 75 eligible patients had complete data. Final diagnoses were as follows: 27/52 (52%), noncardiac; 13/52 (25%), acute myocardial infarction (AMI); and 12/52 (23%), unstable angina due to CAD. Twenty–three percent (12/52) of the patients had CADIs < 75. Eleven of these were found to have noncardiac origins for their chest pain. The twelfth patient had a 12–lead ECG revealing AMI and had been given thrombolytic therapy with subsequent reperfusion prior to VC. Using a CADI < 75 as the cutoff for a negative study, VC alone had a negative predictive value of 92%, a sensitivity of 96%, a positive predictive value of 60%, and a specificity of 41%.
Conclusion: A CADI < 75, in addition to clinical impression and initial ECG, may identify chest pain patients who do not have significant CAD. Further prospective assessment of VC is warranted.     

Referral of discharged emergency department patients to primary and specialty care follow-up

Background

Emergency department (ED) patients often need urgent primary or specialty care follow-up, but access is particularly difficult for those without insurance.

Objective

To characterize follow-up options for uninsured ED patients and to evaluate differences based on ED characteristics.

Methods

We mailed a survey to all ED Directors in Colorado, Georgia, Massachusetts, and Oregon (n = 351 EDs). Typical referrals for urgent primary and specialty care follow-up for uninsured patients were classified as: a) private physician or clinic affiliated with the same hospital; b) external public clinic or university hospital; or c) no referral system/policy.

Results

Of the 298 (85%) responding EDs, 215 (72%) reported primary care referral to private physicians or clinics at the same hospital and 231 (78%) for specialty care. Twenty (7%) and 27 (9%) EDs had no referral system for primary and specialty care, respectively. Factors associated with typical referral to primary care follow-up at the same hospital were: lower visit volume (85% for EDs with < 1 patient per hour vs. 67% for EDs with ≥ 3 patients per hour); rural area (79% for rural vs. 68% for urban areas), and critical access hospital status (81% critical access vs. 69% non-critical access). Conversely, higher visit volume (87% vs. 58%), urban (81% vs. 72%), and non-critical access hospitals (83% vs. 53%) were more likely to refer for specialty care follow-up at the same hospital.

Conclusion

Referral of uninsured ED patients to local follow-up was high for primary and specialty care. Smaller, rural EDs referred within their own hospital more often for primary care but less often for specialty care.     

It is safe to manage selected patients with acute coronary syndromes in unmonitored beds

This prospective, observational study evaluated the safety of the Western Hospital admission protocol for patients with suspected acute coronary syndromes. The study included all patients admitted from the Emergency Department with an admission diagnosis of unstable angina, post infarct angina, atypical chest pain, or chest pain for evaluation. Data collected included demographic data, admission diagnosis, location of admission (bed with or without cardiac monitoring), past medical history and presenting chest pain history to determine Agency for Health Care Policy (AHCPR) and Western Hospital (WH) protocol classifications, cardiac enzyme assays, electrocardiogram analysis, adverse outcomes [death, myocardial infarction (MI), dysrhythmia, acute pulmonary edema, recurrent pain], diagnosis at hospital discharge, and length of stay-(LOS). There were 508 patients with a mean age of 63.7 years enrolled in the study. Three hundred nineteen (62.8%) were admitted to beds without any cardiac monitoring. There was one unexpected death in the unmonitored group, an 85 year-old patient who suffered a presumed dysrhythmia and whom the treating physician had decided was not for resuscitation. Twelve patients suffered nonfatal MI, and none suffered pulmonary edema. All MI patients made an uneventful recovery, and none required thrombolysis. If all patients had been admitted to an area of care based on AHCPR guidelines, an additional 310 admissions to monitored beds would have been required. The results of this study suggest that selected patients with suspected acute coronary syndromes can be safely managed in beds without continuous cardiac monitoring.     

Safety of immediate treadmill testing in selected emergency department patients with chest pain: A preliminary report

To determine the feasibility and safety of an immediate, symptom-limited, treadmill test on selected emergency department (ED) patients, a convenience sample of 28 patients underwent an exercise treadmill test (ETT) within the first several hours after hospital arrival using the modified Bruce protocol. Patients were included in the study if they presented with otherwise unexplained chest pain consistent with (but not characteristic for) angina pectoris and had a normal electrocardiogram. A negative ETT was seen in 23 of 28 patients, and five of 28 patients had a positive ETT. No patients had serial enzyme or electrocardiogram evolution suggestive of myocardial ischemia, and all patients with a negative ETT were discharged after a full inpatient evaluation designed to rule out unstable coronary disease. At a mean follow-up period of 6.1 months there has been no cardiac morbidity or mortality in the patients with negative ETTs. It was concluded that early ETTS of selected ED patients with chest pain is safe, and an exercise test administered during the ED visit which is negative can preclude unnecessary hospitalization.     

Risk stratification of chest pain patients in the emergency department by a nurse utilizing a point of care protocol.

OBJECTIVE: Risk stratification of patients with ischaemic type chest pain assessed in the emergency department utilizing a point of care (POC) protocol. METHODS: Patient demographics, cardiac biomarkers, management and follow-up at 6 months were reviewed for patients seen over 20 months. RESULTS: Out of 546 patients, 351 (64%) were admitted. The diagnoses after admission were confirmed as acute myocardial infarction in 59 patients and unstable angina, (cTroponin T<0.09 ng/ml) in 92 patients. The c-statistic of the receiver operating curves for myocardial infarction (myocardial infarction, cTroponinT at 12 h >0.09 ng/ml) as determined by the POC assay was cTroponin I=0.884, CK-MB=0.883, myoglobin=0.845 and beta-type natriuretic peptide (BNP)=0.755. The c-statistic for the same sample assessed by the hospital laboratory was cTroponin T=0.893: for CK-MB within 12 h of admission it was 0.918; the 12 h cTroponin T was 0.982 and within 24 h of admission NT pro-BNP was 0.789. POC BNP in patients admitted was 68 ng/l (median) vs. 24 ng/l (median) for those not admitted, (P<0.001). POC BNP for patients admitted with unstable angina (12 h cTroponin T <0.09 ng/ml) was 47 ng/l (median, P<0.001). At 6 months, 14 patients had died; five during admission, two within 30 days and seven up to 6 months. During admission two died from heart failure, two with respiratory tract infection and one from carcinoma. Of those not admitted one had died from asbestosis. CONCLUSION: Risk stratification by a specialist nurse utilizing a POC protocol is an appropriate means of assessing patients with chest pain.     

Audit of patients with chest pain presenting to an accident and emergency department over a 6-month period.

The results of a 6-month retrospective audit of patients presenting with chest pain to an accident and emergency (A&E) department to which 46,000 new patients per year present are discussed. The computer diagnostic code assigned to the patients by the A&E doctor, referral rates for second opinion and disposal after assessment in the A&E department are examined, with particular reference to patients who may have had serious cardiac pathology, such as acute myocardial infarction (AMI) or unstable angina. Audit showed that overall 61% of patients with chest pain of all causes were assessed and discharged home by A&E doctors without recourse to second opinion. Of patients thought by the A&E doctors to have chest pain of cardiac origin, who were referred to the duty medical registrar or cardiologist, 88% were admitted. As a result of these findings a policy of more open referral for second opinion was instituted to reduce the likelihood of discharging patients home with serious cardiac pathology. In addition, the clinical problems of AMI and unstable angina are emphasized to all senior house officers early in their educational programme after joining A&E. Published literature on the diagnosis and misdiagnosis of AMI and unstable angina in the A&E department is reviewed. These studies are almost exclusively from North America, and a need for similar work in the U.K. is discussed.     

Emergency-department Diagnosis of Acute Myocardial Infarction and Ischemia: A Cost Analysis of Two Diagnostic Protocols

Objective:To assess the potential cost savings of the emergency-department (ED) diagnosis of acute myocardial infarction (AMI) and other myocardial ischemia using a nine-hour ED evaluation protocol.
Methods:This one-year study of chest-pain evaluation unit (CPEU) patient charges was undertaken at two midwestern urban university hospital EDs. Included in the study were 447 patients presenting to the EDs with chest pain consistent with myocardial ischemia, nondiagnostic electrocardiograms (ECGs), and stable vital signs. Following initial ED evaluation, CPEU patients underwent nine hours of continuous ECG ST-segment monitoring with serum CK-MB levels determined at zero, three, six, and nine hours. Nonrandomized concurrent chest pain patients with routine ED evaluation and hospital admission without CPEU workup served as controls. At Center 1, patients with negative CPEU evaluations underwent immediate echocardiography (echo) and graded exercise testing (GXT) followed by ED release (CPEU;REL). At Center 2, CPEU patients were released from the ED for outpatient stress thallium testing (CPEU; REL). At Center 2, CPEU patients with positive workups as indicated by elevated CK-MB levels, ischemia by ST-segment monitoring, or positive echo/GXT/stress thallium testing were admitted to the hospital for further testing. Control patients were admitted directly to the hospital to evaluate for AMI. Hospital charges for CPEU and control groups were compared.
Results:(Total charges in dollars, mean ± SD, Student's t-test):
Conclusion:At both centers, hospital charges related to the acute evaluation of chest pain were significantly lower with this ED diagnostic protocol for AMI and myocardial ischemia.     

Anxiety and depressive disorders in patients presenting with chest pain to the emergency department: a comparison between cardiac and non-cardiac origin

Objective: The aim of this study was to determine the prevalence of anxiety and depressive disorders in patients presenting with chest pain to the Emergency Department (ED) and determine if there is a relationship between these and cardiac vs. non-cardiac chest pain. Methods: This prospective cross-sectional study was performed in an urban tertiary care hospital between March and October 2005. Consecutive patients presenting with chest pain were enrolled in the study. The prevalence of anxiety and depressive disorders in patients with chest pain were determined by using the Hospital Anxiety and Depression Scale. Results: A total of 324 patients presented to the ED with chest pain during the study period. The mean age of the patients studied was 50.5 ± 14 years; 67% were men and 33% were women. Of the 324 study patients, 194 (59.9%) patients were diagnosed with non-cardiac chest pain, 16 (4.9%) with stable angina, 84 (25.9%) with unstable angina, and 30 (9.3%) with acute myocardial infarction. No statistically significant differences were determined between patients with cardiac and non-cardiac chest pain both for anxiety (40% vs. 38.1%, respectively; p = 0.737) and depressive disorders (52.3% vs. 52.1%, respectively; p = 0.965). Conclusion: Anxiety and depressive disorders are common among patients presenting with chest pain to the ED. However, the prevalence of anxiety and depressive disorders is similar between patients with chest pain of cardiac and non-cardiac origin. Chest pain should not be attributed to an anxiety or depressive disorder before organic etiologies are excluded.     

Effect of exercise treadmill testing and stress imaging on the triage of patients with chest pain: CHEER substudy

OBJECTIVE: To determine whether stress imaging for patients who are unsuitable for exercise treadmill testing (ETT) as part of a chest pain unit (CPU) triage strategy resulted in incremental benefit in clinical outcomes and relative costs compared with patients randomized to routine hospital admission. PATIENTS AND METHODS: Clinical outcomes and medical resource utilization were examined at the Mayo Clinic in Rochester, Minn, for 212 intermediate-risk patients with unstable angina randomized to a CPU and compared with 212 patients randomized to routine admission from November 21, 1995, to March 18, 1997. Patients in stable condition in the CPU underwent ETT; if patients were unsuitable for ETT, stress imaging was performed. Costs for CPU evaluation and outcomes were assessed during a 6-month follow-up. RESULTS: During the observation period, 60 patients (28%) were admitted to the hospital. Of the 152 remaining patients, 125 (82%) underwent ETT (91 had normal results), and 27 (18%) underwent stress imaging (3 had normal results). Patients with normal ETT or stress imaging results had no primary events at 6-month follow-up. Patients admitted to the hospital who underwent stress imaging had an insignificantly higher 6-month event rate compared with patients who underwent ETT (16.7% vs 8.1%; P=.38). The standardized resource-based relative-value units (RBRVUs) for patients who underwent ETT and stress imaging during follow-up were 19.4 and 56.4 RBRVUs, respectively, compared with 51.4 (ETT) and 52.1 (stress imaging) RBRVUs for similar numbers of patients randomized to routine admission. CONCLUSIONS: Exercise treadmill testing safely stratified most intermediate-risk patients with unstable angina and was less costly than routine admission. Patients not suitable for ETT are likely to have abnormal stress imaging results. They represent a higher-risk cohort that could be routinely admitted to the hospital without reducing the effectiveness of the CPU strategy.     

Suspected angina pectoris: a rapid-access chest pain clinic.

We prospectively evaluated a rapid-access chest pain clinic in terms of clinical diagnoses, outcomes, morbidity and mortality at 3 months follow-up in patients, and cost-effectiveness. All patients seen at the clinic from February 1999 to December 2000 were assessed. Referring doctors indicated the management they would have provided had the clinic been unavailable, to allow a cost-effectiveness analysis. Overall, 709 patients were referred, 471 (66%) from General Practitioners, 212 (30%) from Accident and Emergency doctors and 26 (4%) from other sources. All had recent onset, or increasing frequency of ischaemic-type chest pain (excluding those with suspected myocardial infarction or rest chest pain angina). Fifty-one (7%) had acute coronary syndromes, 119 (17%) had stable ischaemic heart disease, 144 (20%) had possible ischaemic heart disease, and 395 (56%) were considered to have non-ischaemic symptoms. Some 70% of patients were seen within 24 h. Only 57 patients (8%) were admitted. Had the clinic been unavailable, 160 patients would have been admitted. Out-patient cardiology appointments were arranged for 116 patients (16%), and 429 patients (60%) were discharged directly. Follow-up data at 3 months were obtained from 565/567 eligible patients (99.6%). No major cardiac events (death/myocardial infarction) occurred in those with non-ischaemic chest pain. There were five deaths (including one due to cancer) and three patients had a myocardial infarction (event rate 1%). There were eleven readmissions for angina: six were in patients with acute coronary syndromes, and four of these six were awaiting revascularization. The estimated net saving was pound 58/patient. A rapid-access chest pain clinic offers a prompt, safe and cost-effective service in a challenging group of patients.     

Emergency Department CK-MB: A Predictor of Ischemic Complications

ABSTRACT
Objective : To demonstrate that a positive CK-MB in the emergency department (ED) predicts an increased risk for complications of myocar-dial ischemia in patients admitted to the hospital for evaluation of chest pain.
Methods : 53 academic and community hospital EDs participated in this prospective observational cohort analysis of 5,120 patients with chest pain without ST-segment elevation on the initial ED 12-lead electrocardiogram. All patients were admitted for evaluation of chest pain in one of the participating hospitals as part of the National Cooperative CK-MB Project. Patients were stratified by whether or not they had an elevated CK-MB level in the ED. CK-MB measurements were made on ED presentation and two hours later. Patient medical records were reviewed for inpatient diagnoses—myocardial infarction (MI) or other diagnosis —and for ischemic complications—cardiac-related death, recurrent or delayed in-hos-pital MI, significant ventricular arrhythmias, new conduction defects, congestive heart failure, and cardiogenic shock.
Results : 369 (7.2%) of the 5,120 patients had MI. The proportion of patients with any complication in the MI group was 24%, while the complication rate in the non-MI group was 0.4%. In all patients, regardless of final diagnosis, the relative risk of any complication was 16.1 (95% CI 11.0–23.6) in those with a positive ED CK-MB versus negative ED CK-MB patients. Similarly, the relative risk of death was 25.4 (95% CI 10.8— 60.2) in positive ED CK-MB versus negative ED CK-MB patients.
Conclusions : Multicenter data support the hypothesis that CK-MB measurements can help risk-stratify ED chest pain patients whose initial ECGs are without diagnostic ST-segment elevation.