Combining Thrombolysis in Myocardial Infarction risk score and clear-cut alternative diagnosis for chest pain risk stratification.

OBJECTIVE: The Thrombolysis in Myocardial Infarction (TIMI) risk score is a validated risk stratification tool useful in patients with definite and potential acute coronary syndromes (ACS) but does not identify patients safe for discharge from the emergency department (ED). Likewise, the use of a clear-cut alternative noncardiac diagnosis risk stratifies patients but does not identify a group safe for discharge. We hypothesized that the presence of an alternative diagnosis in patients with a TIMI risk score less than 2 might identify a cohort of patients safe for ED discharge. METHODS: In prospective cohort study, we enrolled ED patients with potential ACS. Data included demographics, medical history, components of the TIMI risk score, and whether the treating physician ascribed the condition to an alternative noncardiac diagnosis. Investigators followed the patients through the hospital course, and 30-day follow-up was done. The main outcome was 30-day death, myocardial infarction, or revascularization. RESULTS: A total of 3169 patients were enrolled (mean age, 53.6+/-14 years; 45% men; 67% black). There were 991 patients (31%) with an alternative diagnosis, 980 patients with a TIMI risk score of 0, and 828 with a TIMI score of 1. At low levels of TIMI risk (<3), adding in a clinical impression of an alternative diagnosis did not reduce risk; at higher levels of TIMI risk, it did. The incidence of 30-day death, myocardial infarction, or revascularization for patients with a clinical impression of an alternative diagnosis and a TIMI score of 0 was 2.9% (95% confidence interval, 1.6%-5.0%). CONCLUSIONS: The TIMI risk score stratifies patients with and without an alternative diagnosis. Unfortunately, patients with both a low TIMI risk score and a clinical impression of an alternative noncardiac diagnosis still have a risk of 30-day adverse events that is not low enough to allow safe discharge from the ED.

Derivation of a clinical prediction rule for evaluating patients with abdominal pain and diarrhea.

OBJECTIVE: The objective of the study was to develop a simple prediction rule to reliably identify abdominal pain patients with diarrhea who may require surgical intervention. METHODS: We performed a secondary analysis of a prospective cohort study of adults with acute nontraumatic abdominal pain and diarrhea in an urban emergency department (ED). Structured data collection included 109 historical and 28 physical examination items, laboratory and radiographic results, and final diagnosis. The main outcome was operative intervention. RESULTS: One thousand patients were enrolled; 174 patients with diarrhea were included in this analysis. Patients had a mean age of 39 +/- 16 years and were likely to be female (64%) and black (60%). Fifteen (9%) patients received a surgical intervention from the ED. Clinical variables associated with the need for surgical intervention using univariate analysis were age older than 40 years, constant pain, and peritonitis on examination. Using recursive partitioning multivariate analysis, the derived prediction rule included 2 variables: age older than 40 years and constant pain. This rule had a sensitivity of 1.0 (95% confidence interval, 0.78-1.0) and specificity of 0.23 (95% confidence interval, 0.16-0.30). CONCLUSION: Patients older than 40 years with constant abdominal pain and diarrhea are likely to have a surgical cause of their symptoms.

Gender disparity in analgesic treatment of emergency department patients with acute abdominal pain.

OBJECTIVES: Oligoanalgesia for acute abdominal pain historically has been attributed to the provider's fear of masking serious underlying pathology. The authors assessed whether a gender disparity exists in the administration of analgesia for acute abdominal pain. METHODS: This was a prospective cohort study of consecutive nonpregnant adults with acute nontraumatic abdominal pain of less than 72 hours' duration who presented to an urban emergency department (ED) from April 5, 2004, to January 4, 2005. The main outcome measures were analgesia administration and time to analgesic treatment. Standard comparative statistics were used. RESULTS: Of the 981 patients enrolled (mean age +/- standard deviation [SD] 41 +/- 17 years; 65% female), 62% received any analgesic treatment. Men and women had similar mean pain scores, but women were less likely to receive any analgesia (60% vs. 67%, difference 7%, 95% confidence interval [CI] = 1.1% to 13.6%) and less likely to receive opiates (45% vs. 56%, difference 11%, 95% CI = 4.1% to 17.1%). These differences persisted when gender-specific diagnoses were excluded (47% vs. 56%, difference 9%, 95% CI = 2.5% to 16.2%). After controlling for age, race, triage class, and pain score, women were still 13% to 25% less likely than men to receive opioid analgesia. There was no gender difference in the receipt of nonopioid analgesia. Women waited longer to receive their analgesia (median time 65 minutes vs. 49 minutes, difference 16 minutes, 95% CI = 3.5 to 33 minutes). CONCLUSIONS: Gender bias is a possible explanation for oligoanalgesia in women who present to the ED with acute abdominal pain. Standardized protocols for analgesic administration may ameliorate this discrepancy.

Emergency physicians do not use more resources to evaluate obese patients with acute abdominal pain.

OBJECTIVE: We hypothesized that emergency physicians would use more resources to evaluate acute abdominal pain in obese patients as compared with that in nonobese patients. METHODS: We conducted a secondary analysis of a prospective cohort of adults with acute abdominal pain. Collected data included self-reported height and weight, demographics, medical history, laboratory and x-ray results, and final diagnosis. We followed the patients until they obtained their final diagnosis or for up to 21 days. Patients were grouped according to their body mass index (BMI): nonobese (BMI < 30 kg/m2), obese (BMI = 30-40 kg/m2), and morbidly obese (BMI > 40 mg/m2). The main outcome measure was laboratory and radiographic testing. chi2 Tests and analysis of variance were used as appropriate. RESULTS: Of the 971 patients (mean age, 41 years; 62% black; 65% female), 665 (68%) were nonobese, 246 (25%) were obese, and 60 (6%) were morbidly obese. In comparing nonobese patients with obese patients, we found no difference in laboratory or radiographic testing (3.20 vs 3.21 tests; mean difference, 0.004; 95% confidence interval [CI], -0.26 to 0.27), physicians' pre-computed tomographic scan confidence level in their diagnosis (6.17 vs 6.04, mean difference, -0.13; 95% CI, -0.76 to 0.49), and emergency department (ED) length of stay (LOS; 7.40 vs 7.57 hours; mean difference, -0.17; 95% CI, -0.49 to 0.83). In comparing all 3 groups, we found no difference in diagnostic testing, ED LOS, surgical intervention (10% vs 5% vs 9%, P = .2), disposition, and final diagnosis (P > .05). CONCLUSIONS: Physicians do not use more resources to identify the etiology of acute abdominal pain in obese patients as compared with that in nonobese patients. Furthermore, ED LOS, likelihood of surgical intervention, physicians' confidence level in their preimaging diagnosis, and final diagnosis do not appear to be influenced by BMI.

Gender bias in cardiovascular testing persists after adjustment for presenting characteristics and cardiac risk.

OBJECTIVES: Previous studies have found that female patients receive fewer invasive tests for cardiovascular disease than male patients. The authors assessed whether different clinical characteristics at emergency department presentation account for this gender bias. METHODS: Patients with potential acute coronary syndrome (ACS) who presented to a university hospital were prospectively identified. A structured data instrument that included demographic information, chest pain description, history, physical examination, chest radiography, and electrocardiogram (ECG) data was completed. Hospital course was tracked daily. Patients received 30-day telephone follow-up. The main outcome was whether the patients received objective evaluation for coronary artery disease after adjustment for cardiac risk, including race, age, total number of risk factors, Thrombolysis in Myocardial Infarction (TIMI) score, ECG, and whether the patient sustained an acute myocardial infarction on index hospitalization. RESULTS: There were 3,514 women (58%) and 2,547 men (42%) studied. They had similar presenting characteristics: chest pain quality (pressure/tightness: female 60% vs. male 59%, p = 0.6), location (substernal: female 82% vs. male 80%; p = 0.2), radiation (female 27% vs. male 26%; p = 0.3), and most associated symptoms. Men had more cardiac risk factors (mean 1.5 vs 1.4; p < 0.001), more abnormal ECGs (59% vs. 48%; p < 0.001), and a higher TIMI risk score (p < 0.001). With respect to the main outcome, men received more cardiac catheterizations (12.6% vs. 6.0%; odds ratio [OR], 2.25; 95% confidence interval [CI] = 1.88 to 2.70) and more stress tests (14.7% vs. 12.3%; OR, 1.22; 95% CI = 1.05 to 1.42). After adjustment for age, race, cardiac risk factors, ECG, and TIMI risk score, men still received more cardiac catheterizations (adjusted OR, 1.72; 95% CI = 1.40 to 2.11) and stress tests (adjusted OR, 1.16; 95% CI = 1.01 to 1.33). Models adjusting for acute myocardial infarction or death, high-risk initial clinical impression, or emergency department disposition found similar results for increased likelihood of cardiac catheterization in men but no difference in stress testing between men and women. CONCLUSIONS: Female patients with potential ACS receive fewer cardiac catheterizations than male patients, even when presenting complaint, history, ECG, and diagnosis are taken into account. The gender bias cannot be explained by differences in presentation or clinical course.

TIMI risk score: does it work equally well in both males and females?

OBJECTIVE: The TIMI (Thrombolysis In Myocardial Infarction) risk score is a seven item risk stratification tool derived from trials of patients with non-ST segment elevation acute coronary syndromes (ACS) that has been validated in emergency department (ED) patients with potential ACS. We hypothesised that it might have different prognostic abilities in male and female patients. METHODS: This was a prospective cohort study of ED patients with potential ACS. Data included demographics, medical and cardiac history, and components of the TIMI risk score. Investigators followed the hospital course daily. The main outcome was death, acute myocardial infarction (AMI), or revascularisation within 30 days as stratified by TIMI risk score and compared between genders using chi2 tests. RESULTS: There were 2022 patients enrolled: 1204 (60%) females and 818 (40%) males. The incidence of 30 day death, AMI, revascularisation (n = 168) according to TIMI score is as follows (female vs male): TIMI 0 (n = 670), 1.6% vs 2.0%, p = 0.2; TIMI 1 (n = 525), 4.6% vs 8.5%, p = 0.02; TIMI 2 (n = 378), 6.3% vs 10.4%, p = 0.05; TIMI 3 (n = 234), 6.5% vs 24.6%, p<0.001; TIMI 4 (n = 157), 22.7% vs 24.4%, p = 0.15; TIMI 5 (n = 52), 35.5% vs 39.1%, p = 0. 2; TIMI 6 or 7 (n = 6), 33.3% vs 66.7%, p = 1.0. The relationship between TIMI score and outcome was highly significant (p<0.001) for each gender; however, males tended to have worse outcomes at lower TIMI risk scores. CONCLUSIONS: The TIMI risk score successfully risk stratifies both males and females with potential ACS at the time of ED presentation; however, males have worse outcomes at lower TIMI scores than females.

The risk for acute coronary syndrome associated with atrial fibrillation among ED patients with chest pain syndromes.

OBJECTIVE: We sought to determine if atrial fibrillation is associated with an increased risk for an acute coronary syndrome (ACS) among emergency department (ED) patients with chest pain syndromes. METHODS: We performed a retrospective analysis of a prospectively collected database on ED patients with chest pain by selecting patients with atrial fibrillation and frequency-matched control subjects without atrial fibrillation. Measured outcomes were acute myocardial infarction (AMI), ACS, and unstable angina (UA). The relative risks of AMI, ACS, and UA associated with atrial fibrillation were calculated. RESULTS: One hundred forty patients with atrial fibrillation and 683 matched control subjects were identified. The rates of AMI for the atrial fibrillation and control groups were 11.4% and 10.8%, respectively; those of ACS were 27.9% and 26.7%, respectively; and those of UA were 16.4% and 15.8%, respectively. The relative risks of AMI and ACS did not increase in patients with atrial fibrillation: AMI, 1.05 (95% confidence interval [CI] = 0.63-1.75); ACS, 1.05 (95% CI = 0.78-1.40); and UA, 1.05 (95% CI = 0.6-1.7). CONCLUSION: Among patients presenting to the ED with chest pain syndromes, atrial fibrillation is not associated with an increased risk for AMI, ACS, and UA.

Discordance between serum creatinine and creatinine clearance for identification of ED patients with abdominal pain at risk for contrast-induced nephropathy.

STUDY OBJECTIVE: Despite creatinine clearance (CrCl) being a better estimate of renal function, serum creatinine (Cr) is more commonly used to screen for renal insufficiency in patients scheduled for an enhanced abdominal computed tomography (CT) in an attempt to reduce the likelihood of contrast-induced nephropathy (CIN). Our objective was to determine the incidence of renal insufficiency (a CrCl <60 mL/min) among patients who have serum Cr below 1.5 mg/dL (the most commonly accepted Cr cutoff for the administration of intravenous contrast). This study was conducted in a population of emergency department patients with acute abdominal pain being considered for CT scan. METHODS: We performed post hoc analysis of a prospective cross-sectional study that enrolled nongravid adults with acute nontraumatic abdominal pain. Patients on dialysis were excluded. The data that we collected included demographics, history, duration/description of pain, patient reported weight, laboratory data, imaging studies, and final diagnosis. Creatinine clearance values (< or >60 mL/min) were compared to Cr values of 1.0, 1.2, 1.5, and 1.8 mg/dL to determine the percentage of patients at risk for nephropathy after contrast injection at each Cr cutoff. Descriptive statistics were used with 95% confidence intervals (CIs). RESULTS: Seven hundred sixty-five patients were enrolled; 59% (451/765) had an abdominal CT scan. Of 108 patients with CrCl less than 60 mL/min, 59 patients had a Cr less than 1.8 mg/dL (55%; 95% CI, 45%-64%); 43 had a Cr less than 1.5 mg/dL, the most commonly accepted Cr cutoff for contrast administration (40%; 95% CI, 31%-50%); 21 patients had a Cr less than 1.2 mg/dL (19%; 95% CI, 12%-28%); and 10 had a Cr less than 1.0 mg/dL (9%; 95% CI, 5%-16%). CONCLUSION: The most commonly used Cr cutoff (1.5 mg/dL) for contrast administration fails to identify 40% of the patients at risk for CIN. Future studies should address whether using CrCl rather than serum Cr decreases the incidence of contrast-induced nephropathy.

The impact of B-type natriuretic peptide in addition to troponin I, creatine kinase-MB, and myoglobin on the risk stratification of emergency department chest pain patients with potential acute coronary syndrome.

STUDY OBJECTIVE: The emergency department (ED) evaluation of chest pain patients with potential acute coronary syndrome is limited by the initial sensitivity of cell injury markers. BNP is increased during myocardial ischemia and is associated with adverse outcomes. We determine whether the addition of B-type natriuretic peptide (BNP) to troponin I, creatine kinase-MB (CK-MB), and myoglobin increases the sensitivity and negative predictive value (NPV) for acute myocardial infarction, acute coronary syndrome, and 30-day adverse events among chest pain patients with potential acute coronary syndrome. METHODS: A convenience sample of patients aged 30 years or older and presenting to an urban academic ED with nontraumatic chest pain, thus prompting an ECG, was enrolled, and consent was obtained. Blood samples were drawn at 0 and 90 minutes. Thirty-day follow-up was performed for all enrolled patients. Main outcomes were acute myocardial infarction, acute coronary syndrome, and 30-day events (death, acute myocardial infarction, or revascularization). BNP cutoffs were derived from receiver operator characteristics curves. The sensitivity, specificity, positive predictive value (PPV), and NPV with 95% confidence intervals (CIs) were calculated with and without BNP. Differences in sensitivity and specificity with the addition of BNP were calculated with 95% CIs, and McNemar's test was performed to compare sensitivities and specificities. RESULTS: Four hundred twenty-six patients were enrolled and analyzed. The cohort was 54.7+/-13.9 years old, 47.7% men, and 63.5% black. The outcomes were acute myocardial infarction, 39 (9.2%), acute coronary syndrome, 101 (23.7%), and 30-day adverse cardiovascular events 52 (12.2%). BNP cutoffs derived were 51, 31, and 31 pg/mL for acute myocardial infarction, acute coronary syndrome, and 30-day events, respectively. The addition of BNP showed increased sensitivity at the cost of decreased specificity for all 3 outcomes, as follows: (1) acute myocardial infarction: sensitivity: 87.2% (95% CI 72.6% to 95.7%) to 97.4% (95% CI 86.5% to 100%), difference 10.3% (95% CI-0.2% to 24.6%), P=.125; specificity: 62.3% (95% CI 57.2% to 67.1%) to 47.8% (95% CI 42.7% to 52.9%), difference 14.5% (95% CI 11.1% to %18.4), P<.0001; (2) acute coronary syndrome: sensitivity: 75.2% (95% CI 65.7% to 83.3%) to 88.1% (95% CI 80.2% to 93.7%), difference 12.9% (95% CI 7.0% to 21.0%), P=.0002; specificity: 68.0% (95% CI 62.6% to 73.0%) to 48.6% (95% CI 43.1% to 54.2%), difference 19.4% (95% CI 15.2% to 24.1%), P<.0001; (3) 30-day events: sensitivity: 71.2% (95% CI 56.9% to 82.9%) to 88.5% (95% CI 76.6% to 95.7%), difference 17.3% (95% CI 7.7% to 30.3%), P=.004; specificity: 61.8% (95% CI 56.6% to 66.7%) to 43.9% (95% CI 38.8% to 49.0%), difference 17.9% (95% CI 14.2% to 22.2%), P<.0001. There were trends toward increased NPV and decreased PPV for all outcomes, and the addition of BNP achieved a NPV of 99.5% (95% CI 97.0% to 100%) compared with 98.0% (95% CI 95.3% to 99.3%) for acute myocardial infarction. CONCLUSION: The addition of BNP as a dichotomous test to troponin I, CK-MB, and myoglobin produces increased sensitivity at a cost of decreased specificity for acute myocardial infarction, acute coronary syndrome, and 30-day adverse events. Because of this tradeoff, BNP cannot be recommended for use among all ED chest pain patients. However, the improved sensitivity may make this test useful in selected cohorts when the decreased specificity is less important.

Prospective validation of the Thrombolysis in Myocardial Infarction Risk Score in the emergency department chest pain population.

STUDY OBJECTIVE: The Thrombolysis in Myocardial Infarction (TIMI) risk score is a 7-item tool derived from trials of patients with unstable angina/non-ST segment elevation myocardial infarction for risk stratification with respect to outcomes. It has been retrospectively evaluated in emergency department (ED) patients with potential acute coronary syndrome but has not been prospectively validated in this patient population. To validate the use of the TIMI risk score in the ED, we prospectively assess its potential utility in a broad ED chest pain patient population. METHODS: This was a prospective observational cohort study of consecutive ED chest pain patients enrolled from July 2003 until October 2004. Data included demographics, medical and cardiac history, and components of the TIMI risk score. Investigators followed the hospital course daily for admitted patients, and 30-day follow-up was performed on hospitalized and discharged patients. The main outcome was death, acute myocardial infarction, or revascularization as stratified by TIMI risk score at 30 days. RESULTS: There were 1,481 eligible patient visits; 30-day follow-up was completed on 1,458 (98.4%) patients. Patients had mean age of 53.2+/-14 years and were 40% men, 66% black, and 30% white. Myocardial infarction occurred in 95 patients. The incidence of each TIMI risk factor was age greater than 65 years 21%, known coronary stenosis 18%, 3 or more risk factors 26%, ST-segment deviation 6%, 2 or more anginal events in the previous 24 hours 33%, aspirin use in the previous 7 days 35%, and elevated markers 6%. The incidence of 30-day death, acute myocardial infarction, and revascularization according to TIMI score is as follows: TIMI 0, 1.7% (95% confidence interval [CI] 0.42 to 2.95); TIMI 1, 8.2% (95% CI 5.27 to 11.04); TIMI 2, 8.6% (95% CI 5.02 to 12.08); TIMI 3, 16.8% (95% CI 10.91 to 22.62); TIMI 4, 24.6% (95% CI 16.38 to 32.77); TIMI 5, 37.5% (95% CI 21.25 to 53.75); and TIMI 6, 33.3% (95% CI 0 to 100). This relationship was highly significant. CONCLUSION: Among ED patients with chest pain, the TIMI risk score does correlate with outcome. However, in our study the TIMI risk score failed to stratify these patients into discrete groups according to risk score. Also, patients with the lowest risk as defined by a TIMI score of zero had a 1.7% incidence of adverse events. Therefore, the TIMI risk score should not be used in isolation to determine disposition of ED chest pain patients.

Application of the TIMI risk score for unstable angina and non-ST elevation acute coronary syndrome to an unselected emergency department chest pain population.

OBJECTIVES: Patients presenting with chest pain or related symptoms suggestive of myocardial ischemia, without ST-segment elevation (NSTE) on their presenting electrocardiograms, often present a diagnostic challenge in the emergency department (ED). Prompt and accurate risk stratification to identify those patients with NSTE chest pain who are at highest risk for adverse events is essential, however, to optimal management. Although validated and used frequently in patients already enrolled in acute coronary syndrome trials, the Thrombolysis in Myocardial Infarction (TIMI) risk score never has been examined for its value in risk stratification in an all-comers, non-trial-based ED chest pain population. METHODS: An analysis of an ED-based prospective observational cohort study was conducted in 3,929 adult patients presenting with chest pain syndrome and warranting evaluation with an electrocardiogram. These patients had TIMI risk scores determined at ED presentation. The main outcome was the composite of death, acute myocardial infarction (MI), and revascularization within 30 days. RESULTS: The TIMI risk score at ED presentation successfully risk-stratified this unselected cohort of chest pain patients with respect to 30-day adverse outcome, with a range from 2.1%, with a score of 0, to 100%, with a score of 7. The highest correlation of an individual TIMI risk indicator to adverse outcome was for elevated cardiac biomarker at admission. Overall, the score had similar performance characteristics to that seen when applied to other databases of patients enrolled in clinical trials and registries using a 14-day end point. CONCLUSIONS: The TIMI risk score may be a useful tool for risk stratification of ED patients with chest pain syndrome.

Evaluation of a clinical decision rule for young adult patients with chest pain.

OBJECTIVES: The authors sought to validate a clinical decision rule that young adult (younger than 40 years) chest pain patients without known cardiac disease who had either no cardiac risk factors and/or a normal electrocardiogram (ECG) are at low risk (<1%) for acute coronary syndromes (ACS) and 30-day adverse cardiovascular (CV) events. METHODS: A prospective cohort study of patients 24-39 years old who received an ECG for chest pain from July 1999 to March 2002 were included. Cocaine users were excluded. Data collection was structured at presentation, hospital course was followed daily, and 30-day follow-up was obtained by telephone. The main outcome was 30-day adverse CV events (death, acute myocardial infarction, percutaneous intervention, and coronary artery bypass graft). Descriptive statistics were used. RESULTS: Of 4,492 visits for chest pain, 1,023 met criteria. Patients were most often female (61%) and African American (73%). Ninety-eight percent were available for 30-day follow-up. The overall risks of ACS and 30-day adverse CV events were 5.4% and 2.2%, respectively, in our entire cohort. For patients with no cardiac history and no cardiac risk factors, the risk of ACS and 30-day adverse CV events was 1.8%. The risk in patients with no cardiac history and a normal ECG was 1.3%. Patients with no cardiac history, no cardiac risk factors, and a normal ECG had a risk of 1.0%. A modified clinical decision rule found that in young adult patients without a known cardiac history, either no classic cardiac risk factors or a normal ECG, and initially normal cardiac marker studies, the risk of ACS was also extremely low (0.14%) and there were no adverse CV events at 30-day follow-up (95% confidence interval = 0.1% to 0.2%). CONCLUSIONS: A modified clinical decision rule described a group of patients with a 0.14% risk of ACS that was free from 30-day adverse CV events.

Impact of a negative evaluation for underlying coronary artery disease on one-year resource utilization for patients admitted with potential acute coronary syndromes.

UNLABELLED: Reduction in emergency department (ED) overcrowding is a major Joint Commission on the Accreditation of Healthcare Organizations (JCAHO) initiative. One major source of ED overcrowding is patients waiting for telemetry beds. OBJECTIVE: To determine whether, in patients admitted with a potential acute coronary syndrome, a negative evaluation for underlying coronary artery disease would reduce ED and hospital revisits over the subsequent year compared with patients who did not receive an evaluation for underlying coronary artery disease. METHODS: Nine hundred ninety-nine consecutive patients admitted for potential acute coronary syndromes through the ED during a one-year period were screened for inclusion. Patients who had a negative evaluation for underlying coronary disease were compared with patients who were not evaluated for underlying coronary artery disease for subsequent ED visits, hospital admissions, and cardiac resource utilization over the year following the index visit via a health system-wide computerized record review. Patients with positive tests or biomarkers at the index visit were excluded. Each repeat visit was rated as "potentially cardiac" or "noncardiac." Results of echocardiograms, stress tests, and catheterizations and information about in-hospital deaths were obtained. RESULTS: Six hundred ninety-two patients met the inclusion criteria: 556 patients received no evaluation for underlying coronary artery disease, 116 had a negative stress test, and 20 had a negative cardiac catheterization during the index visit. Patients with no evaluation for underlying coronary artery disease and patients with a negative evaluation had similar likelihoods of a repeat ED visit (negative test 39.0% vs. no test 40.3%; p = 0.85) and repeat hospital admission (28.7% vs. 31.5%; p = 0.61). The rates of a potentially cardiac-related ED visit (21.3 vs. 23.4%; p = 0.65) and hospital admission (17.7% vs. 20.7%; p = 0.48) were not significantly different. The two populations had similar utilization rates of echocardiograms, stress tests, and catheterizations (p > 0.70 for all). CONCLUSIONS: For patients admitted to the authors' institution with a potential acute coronary syndrome, there was no association between a negative evaluation for underlying coronary artery disease and overall or potentially cardiac ED visits, admissions, or cardiac resource test utilization over the year following the index visit.

Effects of neural network feedback to physicians on admit/discharge decision for emergency department patients with chest pain.

STUDY OBJECTIVE: Neural networks can risk-stratify emergency department (ED) patients with potential acute coronary syndromes with a high specificity, potentially facilitating ED discharge of patients to home. We hypothesized that the use of "real-time" neural networks would decrease the admission rate for ED chest pain patients. METHODS: We conducted a before-and-after trial. Consecutive ED patients with chest pain were evaluated before and after implementation of a neural network in an urban university ED. Data included 40 variables used in neural networks for acute myocardial infarction and acute coronary syndrome. Data were obtained in real time, and neural network outputs were provided to the treating physician while patients were in the ED. On hospital discharge, attending physicians received feedback, including neural network output, their initial clinical impression, cardiac test results, and final diagnosis. The main outcome was the actual admit/discharge decision made before versus after the implementation of the neural network. RESULTS: Before implementation, 4,492 patients were enrolled; after implementation, 432 patients were enrolled. Implementation of the neural network did not decrease the hospital admission rate (before: 62.7% [95% confidence interval (CI) 61.3% to 64.1%] versus after: 66.6% [95% CI 62.2% to 71.0%]). Additionally, the ICU admission rates were not different (11.4% [95% CI 10.5% to 12.3%] versus 9.3% [95% CI 6.6% to 12.0%]). Physician query found that the neural network changed management in only 2 cases (<1%). CONCLUSION: The use of real-time neural network feedback did not influence the admission decision for ED patients with chest pain, most likely because the neural network output was delayed until the return of cardiac markers, and the disposition decision had already been made by that time.

Assessment of the standardized reporting guidelines ECG classification system: the presenting ECG predicts 30-day outcomes.

STUDY OBJECTIVE: Standardized reporting criteria for risk stratification studies of patients with potential acute coronary syndromes have been proposed. We sought to determine whether the categories in the recommended 6-item ECG classification system predict rates of 30-day death, myocardial infarction, and revascularization. METHODS: We conducted a prospective cohort study of emergency department (ED) chest pain patients who presented to a tertiary care center during a 32-month period. The treating physician classified all ECGs into defined categories. Patients were followed up for 30 days to determine death, myocardial infarction, and revascularization. Our main outcome was the rate of triple composite endpoint of death, myocardial infarction, or revascularization at 30 days from ED presentation in relation to the ECG classification category. RESULTS: There were 3,814 patients who presented to the ED a total of 4,487 times during the study period. Patients had a mean (+/-SD) age of 51.8+/-15.9 years, were more likely to be women (59%) than men, and were most commonly black (68%). The relationship between initial ECG classification and 30-day outcome was highly significant (P<.001), with event rates ranging from 3.2% to 72.7%, depending on ECG classification category. CONCLUSION: The ECG classification system that is being recommended in the standardized guidelines predicts 30-day composite rates of death, acute myocardial infarction, and revascularization.