Cardiac risk factors and risk scores vs cardiac computed tomography angiography: a prospective cohort study for triage of ED patients with acute chest pain.

OBJECTIVE: The objective of the study is to evaluate cardiac risk factors and risk scores for prediction of coronary artery disease (CAD) and adverse outcomes in an emergency department (ED) population judged to be at low to intermediate risk for acute coronary syndrome. METHODS: Informed consent was obtained from consecutive ED patients who presented with chest pain and were evaluated with coronary computed tomography angiography (cCTA). Cardiac risk factors, clinical presentation, electrocardiogram, and laboratory studies were recorded; the Thrombolysis in Myocardial Infarction (TIMI) and Global Registry of Acute Coronary Events (GRACE) scores were tabulated. Coronary computed tomography angiography findings were rated on a 6-level plaque burden scale and classified for significant CAD (stenosis ≥50%). Adverse cardiovascular outcomes were recorded at 30 days. RESULTS: Among 250 patients evaluated by cCTA, 143 (57%) had no CAD, 64 (26%) demonstrated minimal plaque (<30% stenosis), 26 (10%) demonstrated mild plaque (<50% stenosis), 9 (4%) demonstrated moderate single vessel disease (50%-70% stenosis), 2 (1%) demonstrated moderate multivessel disease, and 6 (2%) demonstrated severe disease (>70% stenosis). Six patients developed adverse cardiovascular outcomes. Among traditional cardiac risk factors, only age (older) and sex (male) were significant independent predictors of CAD. Correlation with CAD was poor for the TIMI (r = 0.12) and GRACE (r = 0.09-0.23) scores. The TIMI and GRACE scores were not useful to predict adverse outcomes. Coronary computed tomography angiography identified severe CAD in all subjects with adverse outcomes. CONCLUSION: Among ED patients who present with chest pain judged to be at low to intermediate risk for acute coronary syndrome, traditional risk factors are not useful to stratify risk for CAD and adverse outcomes. Coronary computed tomography angiography is an excellent predictor of CAD and outcome.

Knowledge and attitudes of emergency department patients regarding radiation risk of CT: Effects of age, sex, race, education, insurance, body mass index, pain, and seriousness of illness.

OBJECTIVE: The purpose of this study was to assess knowledge and attitudes about radiation from CT among emergency department patients with symptoms prompting CT who were stratified on the basis of demographic variables, pain, and perceived illness. SUBJECTS AND METHODS: This survey study was based on three knowledge and three attitude questions asked of patients who underwent any CT examination from June 23 through July 31, 2008. Data were analyzed with chi-square for categoric data and the Student's t test or analysis of variance for continuous data. RESULTS: The survey was completed by 383 patients (mean age, 48 ± 18 years; 60% women; 40% black; 52% white; 8% other race). In answering the three knowledge-based questions, 79% and 83% of patients correctly estimated their risk of cancer from chest radiography and CT, respectively, as none, small, or very small. Patients who were white, more educated, and had lower pain scores were more likely to be correct. Only 34% of all patients correctly thought that CT gave more radiation than chest radiography; the more educated patients were more likely to be correct. In answering the three attitude questions, 74% of patients believed having their condition diagnosed with CT was more important than worrying about radiation. Patients preferred a better test with more radiation, although 68% wanted their physician to take the time to discuss the risk and benefits rather than using their judgment to order the best test. Privately insured patients preferred to have their condition diagnosed with CT rather than worry about radiation. Blacks and patients with less pain wanted the risks and benefits explained at the expense of time. Whites preferred a more definitive test at the expense of more radiation. CONCLUSION: Patients did not estimate the risk of development of cancer from their imaging examinations as high and were more concerned about having their condition diagnosed with CT than about the risk of future cancer. Knowledge and attitudes differed by age, race, education, insurance status, and pain level but not by sex, body mass index, or perceived seriousness of condition.

A meta-analysis of 64-section coronary CT angiography findings for predicting 30-day major adverse cardiac events in patients presenting with symptoms suggestive of acute coronary syndrome.

RATIONALE AND OBJECTIVES: To determine the accuracy of 64-section coronary computed tomography angiography (CCTA) in predicting 30 day major adverse cardiac events (MACE) for patients presenting with symptoms concerning for acute coronary syndrome (ACS). MATERIALS AND METHODS: Electronic databases between January 1, 2005, and May, 1, 2011, and reference lists from relevant published research articles were searched. We included studies on adult patients who presented with active symptoms suggestive of ACS, had immediate 64-section CCTA performed and were assessed for MACE at a minimum of 30 days past their initial presentation. Studies had to report or provide sufficient detail to determine sensitivity, specificity, positive predictive value, and negative predictive value in relation to MACE using a 50% diameter stenosis as cutoff criterion for coronary artery disease. RESULTS: Nine studies were included for a total of 1559 patients studied (42.3% women, mean age 51.9 ± 10.6). Patients ranged from low to intermediate risk for ACS. All had initial inconclusive electrocardiograms and negative cardiac biomarker results. A total of 14.8% of patients had a positive CCTA result. The pooled sensitivity was 93.3% (95% CI 88.3%-96.6%), specificity was 89.9% (95% CI 88.3%-91.3%), positive predictive value was 48.1% (95% CI 42.5%-53.8%), and negative predictive value was 99.3% (95% CI 98.7%-99.6%). CONCLUSION: Sixty-four section CCTA had a 99.3% negative predictive value in excluding MACE for 30 days after initial symptom presentation in 85.2% of our study population. Although the value of 64-section CCTA is best for identifying patients who can safely be discharged home, it is less useful for patients who have positive results.

A method for improving arrival-to-electrocardiogram time in emergency department chest pain patients and the effect on door-to-balloon time for ST-segment elevation myocardial infarction.

OBJECTIVES: The objectives were to determine if an emergency department (ED) could improve the adherence to a door-to-electrocardiogram (ECG) time goal of 10 minutes or less for patients who presented to an ED with chest pain and the effect of this adherence on door-to-balloon (DTB) time for ST-segment elevation myocardial infarction (STEMI) cardiac catheterization (cath) alert patients. METHODS: This was a planned 1-month before-and-after interventional study design for implementing a new process for obtaining ECGs in patients presenting to the study ED with chest pain. Prior to the change, patients were registered and triaged before an ECG was obtained. The new procedure required registration clerks to identify those with chest pain and directly overhead page or call a designated ECG technician. This technician had other ED duties, but prioritized performing ECGs and delivering them to attending physicians. A full registration process occurred after the clinical staff performed their initial assessment. The primary outcome was the total percentage of patients with chest pain who received an ECG within 10 minutes of ED arrival. The secondary outcome was DTB time for patients with STEMI who were emergently cath alerted. Data were analyzed using mean differences, 95% confidence intervals (CIs), and relative risk (RR) regression to adjust for possible confounders. RESULTS: A total of 719 patients were studied: 313 before and 405 after the intervention. The mean (+/-standard deviation [SD]) age was 50 (+/-16) years, 54% were women, 57% were African American, and 36% were white. Patients walked in 89% of the time; 11% arrived by ambulance. Thirty-nine percent were triaged as emergent and 61% as nonemergent. Patients presented during daytime 68% of the time, and 32% presented during the night. Before the intervention, 16% received an ECG at 10 minutes or less. After the intervention, 64% met the time requirement, for a mean difference of 47.3% (95% CI = 40.8% to 53.3%, p < 0.0001). Results were not affected by age, sex, race, mode of arrival, triage classification, or time of arrival. For patients with STEMI cath alerts, four were seen before and seven after the intervention. No patients before the intervention had ECG time within 10 minutes, and one of four had DTB time of <90 minutes. After the intervention, all seven patients had ECG time within 10 minutes; the three arriving during weekday hours when the cath team was on site had DTB times of <90 minutes, but the four arriving at night and on weekends when the cath team was off site had DTB times of >90 minutes. CONCLUSIONS: The overall percentage of patients with a door-to-ECG time within 10 minutes improved without increasing staffing. An ECG was performed within 10 minutes of arrival for all patients who were STEMI cath alerted, but DTB time under 90 minutes was achieved only when the cath team was on site.