Ethylene glycol and methanol ingestion cared for by tele-emergency pharmacy and tele-emergency medicine.

We believe this is the first documented case of a critically ill patient managed by telepharmacy in a remote, rural critical access hospital. We outline the case and the benefits of telepharmacy in under-resourced, rural critical access emergency departments.

Impact of an Emergency Department Observation Unit Management Algorithm for Atrial Fibrillation.

BACKGROUND: Atrial fibrillation (AF) is a common, growing, and costly medical condition. We aimed to evaluate the impact of a management algorithm for symptomatic AF that used an emergency department observation unit on hospital admission rates and patient outcomes. METHODS AND RESULTS: This retrospective cohort study compared 563 patients who presented consecutively in the year after implementation of the algorithm, from July 2013 through June 2014 (intervention group), with 627 patients in a historical cohort (preintervention group) who presented consecutively from July 2011 through June 2012. All patients who consented to have their records used for chart review were included if they had a primary final emergency department diagnosis of AF. We observed no significant differences in age, sex, vital signs, body mass index, or CHADS2 (congestive heart failure, hypertension, age, diabetes mellitus, and prior stroke or transient ischemic attack) score between the preintervention and intervention groups. The rate of inpatient admission was significantly lower in the intervention group (from 45% to 36%; P<0.001). The groups were not significantly different with regard to rates of return emergency department visits (19% versus 17%; P=0.48), hospitalization (18% versus 16%; P=0.22), or adverse events (2% versus 2%; P=0.95) within 30 days. Emergency department observation unit admissions were 40% (P<0.001) less costly than inpatient hospital admissions of ≤1 day's duration. CONCLUSIONS: Implementation of an emergency department observation unit AF algorithm was associated with significantly decreased hospital admissions without increasing the rates of return emergency department visits, hospitalization, or adverse events within 30 days.

Chronic kidney disease as a risk factor for acute coronary syndromes in patients presenting to the emergency room with chest pain.

We sought to determine whether persons with intermediate risk factors for cardiovascular disease presenting to an emergency department with chest pain and chronic kidney disease (CKD) were triaged effectively by chest pain units (CPUs). CPUs evaluate patients with intermediate risk and acute chest pain effectively. CKD is a risk factor for poor outcomes once cardiovascular disease has developed. However, current algorithms to risk stratify patients with acute chest pain do not include renal function. A total of 408 patients enrolled previously in the CHEER study of intermediate risk patients with chest pain, assigned randomly to hospitalization or observation in a CPU where an estimated glomerular filtration rate (GFR) was available, were included. No difference was found in short-term outcomes of patients including in-hospital death, myocardial infarction, or coronary revascularization based on renal function. For the 205 patients randomized to the CPU, the rate of admission to the hospital was significantly higher in the group with CKD compared with the group with normal renal function (68.2 vs 48.2%, P=0.007). In a multivariate analysis, decreased renal function was not associated with adverse short-term outcomes. On 5 years follow-up, the overall long-term mortality was significantly higher in the group with CKD (14.1% vs 5.5%, P=0.003). We concluded that CKD is a strong predictor of hospitalization and overall long-term mortality in patients presenting with chest pain to the emergency department. Current risk factor stratification scoring systems should consider CKD as a predictor of increased risk in patients with chest pain.

Outcomes in patients with chest pain evaluated in a chest pain unit: the chest pain evaluation in the emergency room study cohort.

BACKGROUND: Limited data exist on the long-term outcomes of patients who undergo evaluation in a chest pain unit (CPU). METHODS: Our study included patients with chest pain at intermediate risk for acute cardiovascular events enrolled in the CHEER study. The primary outcome included a composite of death, myocardial infarction, acute heart failure, stroke, and out-of-hospital cardiac arrest. The secondary outcome included a composite of cardiovascular death, myocardial infarction, acute heart failure, stroke, revascularization, and unstable angina. Data were obtained through a medical record review. We compared outcomes between groups randomized to the CPU versus admission, those admitted from the CPU versus dismissed home, and those who were admitted versus dismissed home after a cardiac stress test in the emergency department. RESULTS: The final analysis included 407 patients. Median surveillance length was 5.5 years. No differences in the primary outcome or secondary outcome existed between patients randomized to the CPU versus admitted to hospital (21.6% vs 20.2% and 29.9% vs 33.0%, respectively, P > .05 for all comparisons). Patients admitted from the CPU had higher rates of the secondary outcome (adjusted hazard ratio 2.26) than patients dismissed from the CPU. Patients admitted after a cardiac stress test in the CPU had higher rates of the secondary outcome (adjusted hazard ratio 2.42) than patients dismissed from the CPU. CONCLUSIONS: A CPU does not increase long-term adverse outcomes in patients with chest pain at intermediate risk for an acute event.

Long-term cardiovascular outcomes in patients with angina pectoris presenting with bundle branch block.

Long-term outcomes of unselected patients with angina pectoris and bundle branch block (BBB) on initial electrocardiogram are not well established. The Olmsted County Chest Pain Study is a community-based cohort of 2,271 consecutive patients presenting to 3 Olmsted County emergency departments with angina from 1985 through 1992. Patients were followed for major adverse cardiovascular events (MACEs) including death, myocardial infarction, stroke, and revascularization at 30 days and over a median follow-up period of 7.3 years and for mortality only through a median of 16.6 years. Cox models were used to estimate associations between BBB and cardiovascular outcomes. Mean age of the cohort on presentation was 63 years, and 58% were men. MACEs at 30 days occurred in 11% with right BBB (RBBB), 8.8% with left BBB (LBBB), and 6.4% in patients without BBB (p = 0.17). Over a median follow-up of 7.3 years, patients with BBB were at higher risk for MACEs (RBBB, hazard ratio [HR] 1.85, 95% confidence interval [CI] 1.44 to 2.38, p <0.001; LBBB, HR 2.04, 95% CI 1.62 to 2.56, p <0.001) compared to those without BBB. Over a median of 16.6 years, the 2 BBB groups had lower survival rates than patients without BBB (RBBB, HR 2.19, 95% CI 1.73 to 2.78, p <0.001; LBBB, HR 3.32, 95% CI 2.67 to 4.13, p ≤0.001), but after adjustment for multiple risk factors an increased risk of mortality for LBBB remained significant. In conclusion, appearance of LBBB or RBBB in patients presenting with angina predicts adverse long-term cardiovascular outcomes compared to patients without BBB.

Clinical risk stratification in the emergency department predicts long-term cardiovascular outcomes in a population-based cohort presenting with acute chest pain: primary results of the Olmsted county chest pain study.

The long-term cardiovascular outcomes of a population-based cohort presenting to the emergency department (ED) with chest pain and classified with a clinical risk stratification algorithm are not well documented. The Olmsted County Chest Pain Study is a community-based study that included all consecutive patients presenting with chest pain consistent with unstable angina presenting to all EDs in Olmsted County, Minnesota. Patients were classified according to the Agency for Health Care Policy and Research (AHCPR) criteria. Patients with ST elevation myocardial infarction and chest pain of noncardiac origin were excluded. Main outcome measures were major adverse cardiovascular and cerebrovascular events (MACCE) at 30 days and at a median follow-up of 7.3 years, and mortality through a median of 16.6 years.The 2271 patients were classified as follows: 436 (19.2%) as high risk, 1557 (68.6%) as intermediate risk, and 278 (12.2%) as low risk. Thirty-day MACCE occurred in 11.5% in the high-risk group, 6.2% in the intermediate-risk group, and 2.5% in the low-risk group (p < 0.001). At 7.3 years, significantly more MACCE were recorded in the intermediate-risk (hazard ratio [HR], 1.91; 95% confidence intervals [CI], 1.33-2.75) and high-risk groups (HR, 2.45; 95% CI, 1.67-3.58). Intermediate- and high-risk patients demonstrated a 1.38-fold (95% CI, 0.95-2.01; p = 0.09) and a 1.68-fold (95% CI, 1.13-2.50; p = 0.011) higher mortality, respectively, compared to low-risk patients at 16.6 years. At 7.3 and at 16.6 years of follow-up, biomarkers were not incrementally predictive of cardiovascular risk.In conclusion, a widely applicable rapid clinical algorithm using AHCPR criteria can reliably predict long-term mortality and cardiovascular outcomes. This algorithm, when applied in the ED, affords an excellent opportunity to identify patients who might benefit from a more aggressive cardiovascular risk factor management strategy.

Usefulness of diabetes mellitus to predict long-term outcomes in patients with unstable angina pectoris.

The objective of this study was to determine short- and long-term cardiovascular outcomes in unselected patients with diabetes mellitus (DM) with acute ischemic chest pain (AICP). In patients with DM presenting to the emergency department with AICP, short-term cardiovascular outcomes remain discordant between trials and registries, whereas long-term outcomes are not well-described. A consecutive cohort of all residents of Olmsted County, Minnesota, presenting with AICP from January 1, 1985, to December 31, 1992, was followed for a median duration of 16.6 years. The primary outcome was long-term all-cause mortality. Other outcomes included a composite of death, myocardial infarction, stroke, and revascularization (major adverse cardiovascular and cerebrovascular events [MACCEs]) as well as heart failure (HF) events at 30 days and at a median of 7.3 years, respectively. Of the 2,271 eligible patients, 336 (14.8%) were classified with DM. The crude 30-day MACCE rate was 10.1% in patients with DM and 6.1% in those without DM (p = 0.007). HF events were more common in patients with DM at 30 days (9.8% vs 3.1%, p <0.001). At 7.3 years, patients with DM were more likely to experience MACCEs and HF events than those without DM (71.2% vs 45.1%, unadjusted hazard ratio 2.15%, 95% confidence interval 1.87 to 2.48, p <0.001, and 45.1% vs 18.2%, p <0.001, respectively). Over the follow-up period, 272 patients with DM (81.9%) died, compared with 936 (49.2%) without DM (p <0.001). In conclusion, DM is associated with a higher short-term risk for MACCEs and HF and a higher long-term risk for mortality in unselected patients with AICP. DM should be included as a high-risk variable in national acute coronary syndrome guidelines.

A prospective, randomized trial of an emergency department observation unit for acute onset atrial fibrillation.

STUDY OBJECTIVE: An emergency department (ED) observation unit protocol for the management of acute onset atrial fibrillation is compared with routine hospital admission and management. METHODS: Adult patients presenting to the ED with atrial fibrillation of less than 48 hours' duration without hemodynamic instability or other comorbid conditions requiring hospitalization were enrolled. Participants were randomized to either ED observation unit care or routine inpatient care. The ED observation unit protocol included pulse rate control, cardiac monitoring, reassessment, and electrical cardioversion if atrial fibrillation persisted. Patients who reverted to sinus rhythm were discharged with a cardiology follow-up within 3 days, whereas those still in atrial fibrillation were admitted. All cases were followed up for 6 months and adverse events recorded. RESULTS: Of the 153 patients, 75 were randomized to the ED observation unit and 78 to routine inhospital care. Eighty-five percent of ED observation unit patients converted to sinus rhythm versus 73% in the routine care group (difference 12%; 95% confidence interval [CI] -1% to 25%]; P=.06). The median length of stay was 10.1 versus 25.2 hours (difference 15.1 hours; 95% CI 11.2 to 19.6; P<.001) for ED observation unit and inhospital care respectively. Nine ED observation unit patients required inpatient admission. Eleven percent of the ED observation unit group had recurrence of atrial fibrillation during follow-up versus 10% of the routine inpatient care group (difference 1%; 95% CI -9% to 11%; P=.93). There was no significant difference between the groups in the frequency of hospitalization or the number of tests, and the number of adverse events during follow-up was similar in the 2 groups. CONCLUSION: An ED observation unit protocol that includes electrical cardioversion is a feasible alternative to routine hospital admission for acute onset of atrial fibrillation and results in a shorter initial length of stay.

Risk stratification of patients in an emergency department chest pain unit: prognostic value of exercise treadmill testing using the Duke score.

BACKGROUND: Exercise treadmill testing (ETT) has been standard for evaluating outpatients at risk for cardiovascular events. Few studies have demonstrated its prognostic usefulness in emergency department chest pain units or have used the Duke score [(exercise duration in minutes) - (5 x ST-segment deviation in millimeters) - (4 x treadmill angina index)] to grade its performance. AIMS: Our objective was to assess the usefulness of this score in a chest pain unit to predict cardiovascular events. METHODS: From November 2000 to October 2001, we retrospectively studied consecutive patients in the chest pain unit. Those undergoing ETT were stratified into "low" (Duke score > or = 5) and "moderate/high" risk groups (< 5). Cardiovascular events defined as death, myocardial infarction > 24 h after presentation, revascularization, acute congestive heart failure, stroke or arrhythmia were identified within 1 year after presentation. Differences in risk of having a cardiovascular event among low-risk and moderate/high-risk groups are presented. RESULTS: During the study period, 1,048 patients entered the chest pain unit; 800 met inclusion criteria. Of these, 599 received ETT and 201 had contraindications or a positive finding in the chest pain unit protocol before ETT. Cardiovascular event rates were 0.7% (3/454), 15.2% (22/145) and 14.9% (30/201) after 1 month of follow-up for low-risk, moderate/high-risk and no-ETT groups, respectively. CONCLUSIONS: According to the Duke score, the low-risk group developed minimal cardiovascular events compared with the moderate/high-risk group. The Duke score appears effective for risk stratification of chest pain patients in chest pain units.

Syncope evaluation in the emergency department.

PURPOSE OF REVIEW: In the absence of an established critical pathway to evaluate patients with syncope presenting to the emergency department, this review is timely because of new clinical evidences supporting a specialized syncope management unit in the emergency department, and it is relevant because of the potential impact on a very large and heterogeneous population. RECENT FINDINGS: Three observational syncope studies from Italy showed a high degree of variability in practice patterns, diagnostic yields, and lengths of hospital stay. An appropriate and efficacious syncope management pathway in the emergency department remains far from established. In a randomized trial from a tertiary care hospital in the US, the SEEDS study demonstrated that a designated 'syncope unit' in the emergency department, with a multidisciplinary effort and appropriate resources, significantly improved diagnostic yield, reduced hospital admission and total length of hospital stay in intermediate-risk patients. Long-term follow-up showed that reduced hospital stay did not negatively affect survival and recurrent syncope. SUMMARY: Limited randomized trial data suggest a designated syncope unit in the emergency department holds promise to provide specialized and efficient care for patients with syncope. Additional data are needed to assess the general applicability of this critical pathway in community-based hospitals.

Non-invasive resting magnetocardiographic imaging for the rapid detection of ischemia in subjects presenting with chest pain.

BACKGROUND: Early diagnosis of ischemia is complicated by the poor sensitivity of standard tests and contraindication for stress testing in unstable angina patients. Magnetocardiography (MCG) imaging can be used for the rapid, non-invasive detection of ischemia at rest. METHODS: We studied 125 patients with presumed ischemic chest pain. All were chest pain free at the time of scanning. A 6-minute resting MCG scan (CardioMag Imaging, Inc., New York, 9-channel system) was performed. Following the MCG scan, automated software data analysis was performed, and quantitative scores were automatically calculated for each subject. The presence of ischemia was determined after testing with serial troponins, stress testing, and/or coronary angiography. RESULTS: The mean age was 59.4 +/- 13.6 years. Most patients (86.4%) had non-ischemic 12-lead ECG and normal troponin (86.2%). Fifty-five patients (44.0%) were determined to be ischemic. The MCG sensitivity, specificity, positive and negative predictive value was 76.4, 74.3, 70.0 and 80.0%, respectively, for the detection of ischemia (p < 0.0001). CONCLUSIONS: MCG is a new rapid, non-invasive imaging tool able to detect repolarization abnormalities at rest consistent with ischemia in patients presenting with chest pain syndrome and normal or non-specific 12-lead ECG and normal troponin.

Score indices for predicting electrophysiologic outcomes in patients with unexplained syncope.

INTRODUCTION: Our ability to predict a positive electrophysiologic (EP) study in the evaluation of unexplained syncope is suboptimal. AIMS: In patients with unexplained syncope, we defined clinical predictors of bradyarrhythmia and ventricular tachycardia (VT) diagnosed during EP study, constructed diagnostic score indices for bradyarrhythmia and VT, and evaluated the predictive power of each score index. METHODS: All patients evaluated in the Arrhythmia Clinic for unexplained syncope from January 1, 1996, through December 31, 1998, were identified and enrolled in the study. Five hundred eight patients (325 [64%] men; mean+/-SD age, 64+/-17 years) underwent EP testing. We analyzed elements from historical data and noninvasive laboratory findings as predictors of bradyarrhythmia and VT diagnosed on EP study. RESULTS: Fifty-eight patients (11%) had sinus node dysfunction, 94 (19%) had atrioventricular (AV) node disease, 92 (18%) had His-Purkinje system disease, and 101 (20%) had VT. Models were fit using logistic regression analysis. Predictors were assigned weighted scores, and a score index was formulated. The area under the curve associated with sinus node dysfunction, AV node disease, His-Purkinje system disease, and VT models was 0.64, 0.60, 0.84, and 0.60, respectively. CONCLUSIONS: We have constructed diagnostic score indices for EP outcomes of bradyarrhythmia and VT in syncope. Of all the score indices, the model for His-Purkinje system disease has the highest predictive power.

Impact of the application of the American College of Emergency Physicians recommendations for the admission of patients with syncope on a retrospectively studied population presenting to the emergency department.

BACKGROUND: The goal of our study was to determine the accuracy of the American College of Emergency Physicians (ACEP) clinical policy in identifying patients with a cardiac cause for their syncope and its potential effect on syncope management. METHODS: Adult patients with syncope presenting to the emergency department (ED) from January 1996 to December 1998 were identified. Diagnosis was established retrospectively by reviewing medical records. The ACEP guidelines were applied to this population. RESULTS: Of the 200 patients identified, 115 (57.5%, 95% CI 60-64) were admitted from the ED and 24 (12%) were found to have cardiogenic syncope. Of the 24 patients with cardiac syncope, 23 were admitted. By applying ACEP level B recommendations to our population, all patients who on further workup were found to have cardiac syncope would have been admitted from the ED (100% sensitivity, 95% CI 86-100) and 81% of patients with no cardiac syncope would have been discharged from the ED (81% specificity, 95% CI 75-87). The admission rate would have been 28.5% (95% CI 22-35). By extending admission to patients satisfying level C in addition to level B recommendations, the sensitivity, specificity, and admission rate would have been 100% (95% CI 86-100), 33% (95% CI 26-40), and 71.0% (95% CI 64-77), respectively. CONCLUSION: High sensitivity and specificity in identifying patients with cardiogenic syncope and significant reduction in the hospital admission rate were observed by applying ACEP level B recommendations to patients presenting to our ED. Application of level C recommendations did not offer any advantage.

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.

Syncope Evaluation in the Emergency Department Study (SEEDS): a multidisciplinary approach to syncope management.

BACKGROUND: The primary aim and central hypothesis of the study are that a designated syncope unit in the emergency department improves diagnostic yield and reduces hospital admission for patients with syncope who are at intermediate risk for an adverse cardiovascular outcome. METHODS AND RESULTS: In this prospective, randomized, single-center study, patients were randomly allocated to 2 treatment arms: syncope unit evaluation and standard care. The 2 groups were compared with chi2 test for independence of categorical variables. Wilcoxon rank sum test was used for continuous variables. Survival was estimated with the Kaplan-Meier method. One hundred three consecutive patients (53 women; mean age 64+/-17 years) entered the study. Fifty-one patients were randomized to the syncope unit. For the syncope unit and standard care patients, the presumptive diagnosis was established in 34 (67%) and 5 (10%) patients (P<0.001), respectively, hospital admission was required for 22 (43%) and 51 (98%) patients (P<0.001), and total patient-hospital days were reduced from 140 to 64. Actuarial survival was 97% and 90% (P=0.30), and survival free from recurrent syncope was 88% and 89% (P=0.72) at 2 years for the syncope unit and standard care groups, respectively. CONCLUSIONS: The novel syncope unit designed for this study significantly improved diagnostic yield in the emergency department and reduced hospital admission and total length of hospital stay without affecting recurrent syncope and all-cause mortality among intermediate-risk patients. Observations from the present study provide benchmark data for improving patient care and effectively utilizing healthcare resources.

Outcome of patients with a final diagnosis of chest pain of undetermined origin admitted under the suspicion of acute coronary syndrome: a report from the Rochester Epidemiology Project.

STUDY OBJECTIVES: Patients presenting to the emergency department (ED) with chest pain after a recent negative inpatient evaluation for cardiac pathology represent a dilemma for the emergency physician. The purposes of this study were to assess the outcome of patients discharged with a diagnosis of chest pain of undetermined origin and to identify predisposing factors for further cardiac events. METHODS: The resources of the Rochester Epidemiology Project were used to identify all admitted ED patients with chest pain with suspected acute coronary syndrome who received a discharge diagnosis of chest pain of undetermined origin from 1985 through 1992. Patient records were reviewed for the occurrence of adverse cardiac events and subsequent ED visits for recurrent chest pain within 12 months of discharge. Associations between patient characteristics and an adverse cardiac event were evaluated univariately and summarized by using odds ratios (ORs). Long-term mortality was also determined. RESULTS: Among 1,973 admitted ED patients with chest pain, 230 were given a diagnosis of chest pain of undetermined origin. Ten (4.4%) of 230 patients experienced an adverse cardiac event. Factors significantly associated with an adverse cardiac event included an abnormal ECG on admission (OR 9.5; 95% confidence interval [CI] 2.0 to 45.8), preexisting diabetes mellitus (OR 7.1; 95% CI 1.8 to 27.2), and preexisting coronary artery disease (OR 28.4; 95% CI 3.5 to 229.0). Thirty-three (14%) patients returned to the ED within 12 months of discharge; 5 patients were given a diagnosis of a cardiac condition, and 5 were given a diagnosis of a gastrointestinal condition. In long-term follow-up, 46 patients died, with a mean time from hospital discharge to death of any cause of 6.1 years and an estimated 5-year survival of 91.4%. CONCLUSION: Among patients discharged from the hospital with a diagnosis of chest pain of undetermined origin, those with an initial abnormal ECG, preexisting diabetes, or preexisting coronary artery disease are at higher risk of a subsequent adverse cardiac event. In the absence of such factors, cardiac outcome is excellent.

Continuous 12-lead electrocardiographic monitoring in an emergency department chest pain unit: an assessment of potential clinical effect.

STUDY OBJECTIVES: Continuous 12-lead serial ECG monitoring has been proposed to assist in the evaluation of patients with acute coronary syndrome and nondiagnostic ECG in an emergency department chest pain unit. However, the ability of serial ECG to detect acute coronary syndrome and its benefit in addition to a standard protocol has not been established. We evaluate the ability of continuous 12-lead ECG to detect acute coronary syndrome, assess the incremental benefit of the serial ECG in association with a set protocol in an ED chest pain unit, and evaluate whether serial ECG changes could be considered as prognostic factors. METHODS: Patients who met Agency for Health Care Policy and Research guidelines for intermediate risk for short-term cardiovascular event unstable angina were prospectively studied in the chest pain unit. Patients were monitored with the Mortara Instruments ELI 100 STM continuous 12-lead ECG system with ST-segment analysis. ST-segment changes of greater than 100 microV in 2 or more contiguous leads or greater than 200 microV in 1 lead were considered positive. Data were compared with serial serum cardiac markers, cardiac function study results, angiographic results, and 30-day outcome results. RESULTS: One hundred nineteen patients had serial ECG applied. The median duration of monitoring was 4.2 hours. Forty patients were given a diagnosis of acute coronary syndrome. Chest pain unit protocol detected 52 patients, and 23 were given a diagnosis of acute coronary syndrome (sensitivity 58%; specificity 63%). Sixteen patients had ST-segment changes of greater than 100 microV or greater than 200 microV, and 9 were given a diagnosis of acute coronary syndrome. The addition of the serial ECG to the chest pain unit protocol increased the sensitivity to 65% and decreased the specificity to 58%. Two patients with ST-segment changes but none without ST-segment changes had an adverse cardiac event, yielding a sensitivity of 100% and a specificity of 88%. CONCLUSION: Serial ECG is of limited value in the diagnostic evaluation of intermediate-risk patients managed in the chest pain unit with a standard protocol. However, when ST-segment changes are present, they indicate an increased likelihood for an adverse cardiac event.