Interprofessional/interdisciplinary teamwork during the early COVID-19 pandemic: experience from a children's hospital within an academic health center.

The COVID-19 pandemic has created multiple, complex and intense demands on hospitals, including the need for surge planning in the many locations outside epicenters such as northern Italy or New York City. We here describe such surge planning in an Academic Health Center that encompasses a children's hospital. Interprofessional teams from every aspect of inpatient care and hospital operations worked to prepare for a COVID-19 surge. In so doing, they successfully innovated ways to integrate pediatric and adult care and maximize bed capacity. The success of this intense collaborative effort offers an opportunity for ongoing teamwork to enhance efficient, effective, and high-quality patient care.

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

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

Upstream treatment of acute coronary syndrome in the ED.

Rapid risk stratification, selection of downstream management options, and institution of initial pharmacotherapy are essential to ensure that patients admitted to the emergency department with acute coronary syndromes receive optimal care. A broad range of antiplatelet and antithrombotic medications is available that permits tailoring of initial pharmacotherapy to each patient's risk status. In the urgent setting, thienopyridines (clopidogrel and prasugrel) carry limitations including response variability and increased risk for bleeding in patients requiring subsequent coronary artery bypass graft surgery. Glycoprotein IIb-IIIa receptor inhibitors, although they are highly effective in preventing ischemic events, must be used with care to reduce bleeding risk. Bivalirudin, a relatively new direct thrombin inhibitor, represents another upstream option but is costly and does not have approval for this indication. Simplified institutional management paradigms can streamline the process of selecting appropriate pharmacotherapy and aid in care delivery that will optimize patient outcomes.

Pharmacologic stabilization and management of acute heart failure syndromes in the emergency department.

Effective use of diuretics, vasodilators, and inotropes to stabilize acute heart failure (AHF) relies on matching the most appropriately tailored therapy to specific clinical profiles. Some of the drugs may be harmful, and therefore the emphasis should be on patient safety and the attempt to minimize the deleterious effects of these therapies. To date, successful treatment has been limited because no agent has been shown to reduce postdischarge mortality or readmission rates, and patients frequently remain symptomatic after treatment. Ongoing research is needed to further examine these agents and to develop novel therapies to address the unmet needs of the patient who has AHF.

Beyond pulmonary edema: diagnostic, risk stratification, and treatment challenges of acute heart failure management in the emergency department.

The majority of heart failure hospitalizations in the United States originate in the emergency department (ED). Current strategies for acute heart failure syndromes have largely been tailored after chronic heart failure guidelines and care. Prospective ED-based acute heart failure syndrome trials are lacking, and current guidelines for disposition are based on either little or no evidence. As a result, the majority of ED acute heart failure syndrome patients are admitted to the hospital. Recent registry data suggest there is a significant amount of heterogeneity in acute heart failure syndrome ED presentations, and diagnostics and therapeutics may need to be individualized to the urgency of the presentation, underlying pathophysiology, and acute hemodynamic characteristics. A paradigm shift is necessary in acute heart failure syndrome guidelines and research: prospective trials need to focus on diagnostic, therapeutic, and risk-stratification algorithms that rely on readily available ED data, focusing on outcomes more proximate to the ED visit (5 days). Intermediate outcomes (30 days) are more dependent on inpatient and outpatient care and patient behavior than ED management decisions. Without these changes, the burden of acute heart failure syndrome care is unlikely to change. This article proposes such a paradigm shift in acute heart failure syndrome care and discusses areas of further research that are necessary to promote this change in approach.

Bronchodilator therapy in acute decompensated heart failure patients without a history of chronic obstructive pulmonary disease.

STUDY OBJECTIVE: Inhaled bronchodilators are often used in the emergency department (ED) before a definitive diagnosis is made. We evaluated the association between inhaled bronchodilators and outcomes in acute decompensated heart failure patients without chronic obstructive pulmonary disease. METHODS: We conducted an analysis of the Acute Decompensated Heart Failure National Registry Emergency Module registry of patients with a principal discharge diagnosis of acute decompensated heart failure enrolled at 76 academic or community EDs. Dichotomous outcomes (mortality, ED discharges, ICU admission, ED i.v. vasodilator use, new dialysis, ED or in patient endotracheal intubation, ED BiPAP, and asymptomatic at discharge) in patients without a history of chronic obstructive pulmonary disease who were given bronchodilators were compared to those who were not given bronchodilators using logistic regression; odds ratios (ORs) and 95% confidence intervals (CIs) were calculated; and propensity score adjustments were made. RESULTS: Of the 10,978 patients enrolled, 7299 (66.5%) did not have a history of chronic obstructive pulmonary disease. Bronchodilators were administered by the EMS or in the ED to 2317 (21%) patients. Patients without chronic obstructive pulmonary disease given bronchodilators were more likely to receive ED i.v. vasodilators (28.4% vs. 16.9%; propensity adjusted OR 1.40 [95% CI 1.18-1.67]) and in-patient mechanical ventilation (6.0% vs. 2.4%; propensity adjusted OR 1.69 [95% CI 1.21-2.37]) than patients without chronic obstructive pulmonary disease who were not given bronchodilators. Hospital mortality in patients without chronic obstructive pulmonary disease was similar regardless of bronchodilator treatment (3.4% vs. 2.6%, propensity adjusted OR 1.02 [95% CI 0.67, 1.56]). CONCLUSION: Many acute decompensated heart failure patients without a history of chronic obstructive pulmonary disease receive inhaled bronchodilators. Bronchodilator use was associated with a greater need for aggressive interventions and monitoring, and this may reflect an adverse effect of bronchodilators or it may be a marker for patients with more severe disease.

Design and rationale of the URGENT Dyspnea study: an international, multicenter, prospective study.

BACKGROUND: Dyspnea is a key target in both clinical management and clinical trials of acute heart failure syndromes and its relief important to patients, clinicians, investigators, and regulatory approval agencies. Despite its importance, the impact of early therapy on dyspnea is not well known. The severity of dyspnea may also be influenced by the conditions under which it is measured (ie, sitting up or lying down). URGENT Dyspnea (Ularitide Global Evaluation in Acute Decompensated Heart Failure) is a prospective multicenter study designed to address these issues. METHODS AND RESULTS: Consenting adult patients with dyspnea secondary to acute heart failure syndromes are eligible. Patients must be interviewed within one hour of first physician evaluation, typically in an emergency department or acute care setting, with dyspnea assessed by the patient using both a 5-point Likert scale and 10-point visual analog scale in the sitting (60 degrees) and then supine (20 degrees ) position if symptomatically able. Improvement of dyspnea by change in Likert and visual analog scale scores at 6 h is the primary endpoint. CONCLUSIONS: Timing of dyspnea measurement and the conditions under which it is measured may influence dyspnea severity and this may have significant implications for future acute heart failure syndromes clinical trial design that target dyspnea.

Prognostic value of troponins in patients with non-ST-segment elevation acute coronary syndromes and chronic kidney disease.

BACKGROUND: The prognostic value of cardiac troponins (cTn) in patients with non-ST-segment elevation acute coronary syndromes (NSTE ACS) and chronic kidney disease (CKD) is debated. HYPOTHESIS: We tested the performance of cTnI and cTnT for risk stratification in patients with CKD and evaluated the prognostic significance of cTnI and cTnT elevations by their magnitude across the range of CKD severity. METHODS: We examined correlations among cTn elevation, CKD, and in-hospital mortality in 31,586 high-risk patients with NSTE ACS included in the Can Rapid Risk Stratification of Unstable Angina Patients Suppress ADverse Outcomes with Early Implementation of the American College of Cardiology/American Heart Association Guidelines initiative (CRUSADE). Cardiac tropinins I and T levels were categorized as ratios of each site's upper limit of normal (ULN) for myocardial necrosis: normal (cTn ratio < or =1 x ULN), mild (cTn ratio > 1-3 x ULN), and major (cTn ratio > 3 x ULN) elevation. Estimated glomerular filtration rate (eGFR) was calculated using the abbreviated Modification of Diet in Renal Disease equation. Stages of CKD were categorized as normal to mild (eGFR > 60 mL/min), moderate (eGFR 30-60 mL/min), or severe (eGFR < 30 mL/min). RESULTS: Mortality increased more steeply across CKD stages (2.0%-12.9%) than across cTn ratio categories (2.7%-5.4%). In normal or mild CKD, mortality was low regardless of cTn elevations. In moderate CKD, mortality increased incrementally with cTnI (3.3% versus 5.4% versus 7.4%) and cTnT (3.7% versus 5.3% versus 7.3%) elevation. Among severe CKD patients, only major cTn elevations further distinguished risk (cTnI: 10.1% versus 9.7% versus 14.6%; cTnT: 7.0% versus 5.7% versus 14.0%). CONCLUSIONS: In patients with CKD, cTnI and cTnT perform equally in differentiating short-term prognosis following NSTE ACS; however, the prognostic impact of cTn is dependent upon the degree of CKD severity.

Prolonged emergency department stays of non-ST-segment-elevation myocardial infarction patients are associated with worse adherence to the American College of Cardiology/American Heart Association guidelines for management and increased adverse events.

STUDY OBJECTIVE: We evaluate the association of emergency department (ED) length of stay with use of guideline-recommended therapies for acute treatments and clinical outcomes. Prolonged ED stays often reflect ED crowding or limited hospital capacity. We hypothesized that patients with non-ST-segment-elevation myocardial infarction who have ED stays of greater than 8 hours may have lower quality of care and worse outcomes. METHODS: Using a secondary analysis of data from an observational registry (Can Rapid Risk Stratification of Unstable Angina Patients Suppress ADverse Outcomes with Early Implementation of the ACC/AHA Guidelines, CRUSADE), we compared rates of use of 5 individual acute (<24 hours) guideline-recommended therapies in patients with non-ST-segment-elevation myocardial infarction according to ED length of stay. Patients were grouped by length of stay (short [<4 hours], average [4 to 8 hours], or long [>8 hours]). Multivariable analyses were used to determine independent association of ED length of stay with acute medications and inhospital outcomes (death and myocardial infarction). RESULTS: This analysis included 42,780 patients with non-ST-segment-elevation myocardial infarction. The median ED length of stay was 4.3 hours (25th to 75th percentile 2.9, 6.3); 15% of patients stayed longer than 8 hours. Patients who had long ED stays were more likely to be women and nonwhite and less likely to have health maintenance organization or private insurance. After adjustment, patients with long ED stays less often received guideline-recommended acute myocardial infarction therapies. Although risk-adjusted inhospital mortality rates were similar among groups, the rate of recurrent myocardial infarction increased among patients with long ED stays (odds ratio 1.23; 95% confidence interval 1.01 to 1.48) compared with those with average ED length of stay. CONCLUSION: For patients with non-ST-segment-elevation myocardial infarction, long ED stays were associated with decreased use of guideline-recommended therapies and a higher risk of recurrent myocardial infarction. However, there was no observed difference in mortality. Factors associated with prolonged ED length of stay should be evaluated to optimize treatments and outcomes of patients with non-ST-segment-elevation myocardial infarction.

The obesity paradox in non-ST-segment elevation acute coronary syndromes: results from the Can Rapid risk stratification of Unstable angina patients Suppress ADverse outcomes with Early implementation of the American College of Cardiology/American Heart Association Guidelines Quality Improvement Initiative.

BACKGROUND: Although obesity is a known risk factor for coronary artery disease, its impact on the presentation, treatment, and outcome of patients with acute coronary syndromes (ACS) has not been well studied. METHODS: Using data from the CRUSADE Initiative, we compared inhospital treatments and clinical outcomes of 80845 patients with high-risk non-ST-segment elevation (NSTE) ACS (positive cardiac markers and/or ischemic ST-segment changes) to determine whether there was an association with body mass index (BMI [kg/m2]). Patient weights were categorized according to World Health Organization classifications: Underweight (BMI <18.5), Normal range (BMI 18.5-24.9), Overweight (BMI 25-29.9), Obese Class I (BMI 30-34.9), Obese Class II (BMI 35-39.9), and Extremely Obese (BMI =40). RESULTS: Most (70.5%) of the CRUSADE patients were classified as overweight or obese; these patients were younger and more likely to present with comorbid conditions, including diabetes mellitus, hypertension, and hyperlipidemia. Medications given during the first 24 hours and invasive cardiac procedures recommended by the American College of Cardiology/American Heart Association guidelines for NSTE ACS were more commonly used in these patients. The incidence of death and death and reinfarction, adjusted for covariates, were generally lower in overweight and obese patients, compared with normal-weight patients, but higher in underweight and extremely obese patients. CONCLUSIONS: Most patients with NSTE ACS are overweight or obese. These patients receive more aggressive treatment, and, except for the extremely obese, have less adverse outcomes compared with underweight and normal-weight patients. Although obesity appears to be a risk factor for developing ACS at a younger age, it also appears to be associated with more aggressive ACS management and, ultimately, improved outcomes.

Frequency and consequences of recording an electrocardiogram >10 minutes after arrival in an emergency room in non-ST-segment elevation acute coronary syndromes (from the CRUSADE Initiative).

We sought to determine the frequency of electrocardiographic (ECG) acquisition within 10 minutes of hospital arrival, factors associated with delayed ECG acquisition, and any relation among delayed ECG acquisition, treatment patterns, and clinical outcomes. We therefore analyzed data from 63,478 patients (26,615 women, 42%) with high-risk non-ST-segment elevation acute coronary syndromes (designated by positive cardiac markers and/or ischemic ST-segment changes) who were enrolled in the CRUSADE Quality Improvement Initiative from February 2001 to March 2004. Patients were categorized based on time to electrocardiography as delayed (>10 minutes from hospital arrival) or nondelayed (<10 minutes). Multivariable predictors of delayed ECG acquisition were determined. Overall, median time to electrocardiography was 15 minutes (25th to 75th percentile 7 to 32). ECG acquisition was delayed (median 25 minutes, 25th to 75th percentile 16 to 50) in 41,397 patients (65.2%). In the remaining 34.8%, time to electrocardiography was <10 minutes (median 5 minutes, 25th to 75th percentile 3 to 8). Women were more likely than men to have delayed ECG acquisition (69% vs 62%), and female gender was the most significant predictor of delayed ECG acquisition (odds ratio 1.29, 95% confidence interval 1.25 to 1.34). In conclusion, only 33% of high-risk patients with non-ST-segment elevation acute coronary syndrome had an initial electrocardiogram obtained <10 minutes of arrival as recommended. Women were significantly more likely than men to have delayed ECG acquisition. Emergency departments should focus on decreasing the time to initial ECG acquisition to improve treatment of acute coronary syndrome in this group.

The Internet Tracking Registry of Acute Coronary Syndromes (i*trACS): a multicenter registry of patients with suspicion of acute coronary syndromes reported using the standardized reporting guidelines for emergency department chest pain studies.

STUDY OBJECTIVE: Observational studies of well-described patient populations presenting to emergency departments (EDs) with suspicion of acute coronary syndrome are necessary to understand the relationships between patients' signs and symptoms, cardiac risk profile, test results, practice patterns, and outcomes. We describe the methods for data collection and the ED population enrolled in a multicenter registry of patients with chest pain. METHODS: Patients older than 18 years, presenting to one of 8 EDs in the United States or 1 ED in Singapore, and with possible acute coronary syndrome were enrolled in the Internet Tracking Registry of Acute Coronary Syndromes between June 1999 and August 2001. Prospective data, including presenting signs and symptoms, ECG findings, and the ED physician's initial impression of risk, were systematically collected. Medical record review or daily follow-up was used to obtain cardiac biomarker results, invasive and noninvasive testing, treatments, procedures, and inhospital outcomes. Thirty-day outcomes were determined by telephone follow-up and medical record review. RESULTS: The registry includes 15,608 patients, with 17,713 visits. Chest pain was the chief complaint in 71% of visits. The ECG was diagnostic of ischemia or infarction in 10.1% and positive cardiac biomarkers were observed in 10% of visits. Forty-three percent of patients were sent home directly from the ED. Of admitted patients, 5% died by 30 days, and 3% had documented coronary artery disease or had undergone percutaneous coronary intervention or coronary artery bypass grafting within 30 days. For patients discharged directly from the ED, 0.4% died or had a documented myocardial infarction within 30 days. Coronary artery bypass graft surgery, percutaneous coronary intervention, or a diagnosis of coronary artery disease was found in 0.5% of discharged patients. CONCLUSION: A unique description of undifferentiated ED chest pain patients with suspected acute coronary syndrome is provided. The data set can be used to generate and explore hypotheses to improve understanding of the complex relationships between presentation, treatment, testing, intervention and outcomes.

Comparison of the HEART and TIMI Risk Scores for Suspected Acute Coronary Syndrome in the Emergency Department.

OBJECTIVES: The emergency department evaluation for suspected acute coronary syndrome (ACS) is common, costly, and challenging. Risk scores may help standardize clinical care and screening for research studies. The Thrombolysis in Myocardial Infarction (TIMI) and HEART are two commonly cited risk scores. We tested the null hypothesis that the TIMI and HEART risk scores have equivalent test characteristics. METHODS: We analyzed data from the Internet Tracking Registry of Acute Coronary Syndromes (i*trACS) from 9 EDs on patients with suspected ACS, 1999-2001. We excluded patients with an emergency department diagnosis consistent with ACS, or without sufficient data to calculate TIMI and HEART scores. The primary outcome was 30-day major adverse cardiovascular events, including all-cause death, acute myocardial infarction, and urgent revascularization. We describe test characteristics of the TIMI and HEART risk scores. RESULTS: The study cohort included 8255 patients with 508 (6.2%) 30-day major adverse cardiovascular events. Receiver operating curve and reclassification analyses favored HEART [c statistic: 0.753, 95% confidence interval (CI): 0.733-0.773; continuous net reclassification improvement: 0.608, 95% CI: 0.527-0.689] over TIMI (c statistic: 0.678, 95% CI: 0.655-0.702). A HEART score 0-3 [negative predictive value (NPV) 0.982, 95% CI: 0.978-0.986; positive predictive value (PPV) 0.103, 95% CI: 0.094-0.113; likelihood ratio (LR) positive 1.76; LR negative 0.28] demonstrates similar or superior NPV/PPV/LR compared with TIMI = 0 (NPV 0.978, 95% CI: 0.971-0.983; PPV 0.077, 95% CI: 0.071-0.084; LR positive 1.28; LR negative 0.35) and TIMI = 0-1 (NPV 0.963, 95% CI: 0.958-0.968; PPV 0.102, 95% CI: 0.092-0.113; LR positive 1.73; LR negative 0.58). CONCLUSIONS: The HEART score has better discrimination than TIMI and outperforms TIMI within previously published "low-risk" categories.

Association of Early Stress Testing with Outcomes for Emergency Department Evaluation of Suspected Acute Coronary Syndrome.

BACKGROUND: Professional society guidelines suggest early stress testing (within 72 hours) after an emergency department (ED) evaluation for suspected acute coronary syndrome (ACS). However, there is increasing concern that current practice results in over-testing without evidence of benefit. We test the hypothesis that early stress testing improves outcomes. METHODS: We analyzed prospectively collected data from 9 EDs on patients with suspected ACS, 1999-2001. We excluded patients with an ED diagnosis of ACS. The primary outcome was 30-day major adverse cardiac events (MACEs), including all-cause death, acute myocardial infarction, and revascularization. We used the HEART score to determine pretest ACS risk (low, intermediate, and high). To mitigate potential confounding, patients with and without early stress testing were matched within pretest risk strata in a 1:2 ratio using propensity scores. RESULTS: Of 7127 potentially eligible patients, 895 (13%) received early stress testing. The analytic cohort included 895 patients with early stress testing matched to 1790 without early stress testing. The overall 30-day MACE rate in both the source and analytic population was 3%. There were no baseline imbalances after propensity score matching (P > 0.1 for more than 30 variables). There was no association between early stress testing and 30-day MACE [odds ratio, 1.0; 95% confidence interval (CI), 0.6-1.7]. There was no effect modification by pretest risk (low: odds ratio, 1.0; 95% CI, 0.2-3.7; intermediate: 1.2; 95% CI, 0.6-2.6; high: 0.4; 95% CI, 0.1-1.6). CONCLUSIONS: Early stress testing is not associated with reduced MACE in patients evaluated for suspected ACS. Early stress testing may have limited value in populations with low MACE rate.

Immediate exercise testing to evaluate low-risk patients presenting to the emergency department with chest pain.

OBJECTIVES: Our purpose was to determine the safety and accuracy of immediate exercise testing in low-risk patients presenting to the emergency department (ED) with chest pain suggestive of a cardiac etiology. BACKGROUND: Safe, efficient management of low-risk patients presenting to the ED with chest pain is a continuing challenge. We have employed immediate exercise testing to evaluate a large, heterogeneous group of low-risk patients presenting with chest pain. METHODS: Patients presenting to the ED with chest pain compatible with a cardiac origin and clinical evidence of low risk on initial assessment underwent immediate exercise treadmill testing in our chest pain evaluation unit. Indicators of low clinical risk included no evidence of hemodynamic instability, arrhythmias or electrocardiographic signs of ischemia. Serial measurements of cardiac injury markers were not obtained. RESULTS: Exercise testing was performed to a sign- or symptom-limited end point in 1,000 patients (520 men, 480 women; age range 31 to 82 years) and was positive for ischemia in 13%, negative in 64% and nondiagnostic in 23% of patients. There were no adverse effects of exercise testing, and all patients with a negative exercise test were discharged directly from the ED. At 30-day follow-up there was no mortality in any of the three groups. Cardiac events in the three groups included: negative group, 1 non-Q-wave myocardial infarction (MI); positive group, 4 non-Q-wave MIs and 12 myocardial revascularizations; nondiagnostic group, 7 myocardial revascularizations. BACKGROUND: Immediate exercise testing of patients presenting to the ED with chest pain and evidence of low clinical risk is safe and accurate for determining those who require admission and those who can be discharged to further outpatient evaluation.

Changes in the numeric descriptive scale for pain after sublingual nitroglycerin do not predict cardiac etiology of chest pain.

STUDY OBJECTIVE: We determine whether the change in numeric descriptive scale for pain after sublingual nitroglycerin use can predict cardiac etiology of chest pain. METHODS: A prospective study of a convenience sample of patients who had chest pain, presented to the emergency department from May 24, 2001, to April 30, 2002, and received sublingual nitroglycerin during their evaluation was performed. The 11-point numeric descriptive scale for chest pain was recorded before and after the initial dose of sublingual nitroglycerin. Cardiac-related pain was defined as chest pain in a patient with a discharge diagnosis of myocardial infarction or the diagnosis of coronary artery disease based on a positive diagnostic study (cardiac catheterization or noninvasive stress imaging). Change in the numeric descriptive scale was divided into 4 categories: (1) significant/complete reduction; (2) moderate reduction; (3) minimal reduction; and (4) no change. RESULTS: The study cohort was composed of 664 patients: 345 women (52%) and 319 men (48%), mean age 52 years (+/-12.4 years). Cardiac-related chest pain was identified in 122 patients (18%). In the overall patient population, 125 (19%) patients had no change in pain, 206 (31%) patients had minimal reduction, 145 (22%) patients had moderate reduction, and 188 (28%) patients had significant or complete reduction in pain. There was no significant difference in any subgroup of numeric descriptive scale response to sublingual nitroglycerin administration in patients with and without a diagnosis of cardiac chest pain. CONCLUSION: In this convenience sample, the response of chest pain to sublingual nitroglycerin was not a reliable indicator of a cardiac etiology.

Influence of timing of troponin elevation on clinical outcomes and use of evidence-based therapies for patients with non-ST-segment elevation acute coronary syndromes.

STUDY OBJECTIVE: Previous studies in clinical trial populations have demonstrated that patients presenting with positive troponin levels have a higher risk of mortality than patients with later positive troponin levels, but the influence of the timing of troponin elevation has not been previously characterized. We evaluate the impact of the timing of troponin elevation on clinical outcomes and adherence to the American College of Cardiology/American Heart Association acute care guidelines for patients with non-ST-segment elevation acute coronary syndromes. METHODS: We examined inhospital outcomes and use of acute (<24 hours) medications and invasive cardiac procedures in 23,184 high-risk patients with non-ST-segment elevation acute coronary syndromes (positive cardiac markers or ischemic ST-segment changes) during 2001 to 2002 from 396 US hospitals participating in the Can Rapid Risk Stratification of Unstable Angina Patients Suppress ADverse Outcomes with Early Implementation of the American College of Cardiology/American Heart Association Guidelines (CRUSADE) Initiative. Baseline and peak troponin values were recorded and were designated as positive if above the cutoff value used at each institution to designate definite myocardial necrosis. RESULTS: In the study cohort, 53.2% of patients presented with baseline positive troponin levels, 30.6% had baseline negative/later positive troponin levels, and 16.2% had negative troponin levels during the entire hospitalization. Patients with baseline positive troponin levels had a higher risk of inhospital mortality than patients with baseline negative/later positive troponin levels (6.5% versus 4.1%) and were less likely to undergo early cardiac catheterization or percutaneous coronary intervention. The use of acute aspirin (in approximately 91% of patients), heparin (85%), and beta-blockers (78%) was similar in patients with baseline-positive versus later-positive troponin levels. CONCLUSION: These findings demonstrate that evidence-based therapies and interventions for non-ST-segment elevation acute coronary syndromes are underused in patients with elevated troponin levels, but baseline troponin elevations, which are associated with a higher risk of inhospital mortality, do not stimulate more aggressive care.