Emergency Physician High Pretest Probability for Acute Coronary Syndrome Correlates with Adverse Cardiovascular Outcomes

Abstract

Objectives: The value of unstructured physician estimate of risk for disease processes, other than acute coronary syndrome (ACS), has been demonstrated. The authors sought to evaluate the predictive value of unstructured physician estimate of risk for ACS in emergency department (ED) patients without obvious initial evidence of a cardiac event.Methods: This was a post hoc secondary analysis of the Internet Tracking Registry for Acute Coronary Syndromes (i*trACS), a prospectively collected multicenter data registry of patients over the age of 18 years presenting to the ED with symptoms of ACS between 1999 and 2001. In this registry, following patient history, physical exam, and electrocardiogram (ECG), the unstructured treating physician estimate of risk was recorded. A 30-day follow-up and a medical record review were used to determine rates of adverse cardiac events, death, myocardial infarction (MI), or revascularization procedure. The analysis included all patients with nondiagnostic ECG changes, normal initial biomarkers, and a non-MI initial impression from the registry and excluded those without complete data or who were lost to follow-up. Data were stratified by unstructured physician risk estimate: noncardiac, low risk, high risk, or unstable angina.Results: Of 15,608 unique patients in the registry, 10,145 met inclusion ⁄ exclusion criteria. Patients were defined as having unstable angina in 6.0% of cases; high risk, 23.5% of cases; low risk, 44.2%; and noncardiac, 26.3% of cases. Adverse cardiac event rates had an inverse relationship, decreasing from 22.0% (95% confidence interval [CI] = 18.8% to 25.6%) for unstable angina, 10.2% (95% CI = 9.0% to 11.5%) for those stratified as high risk, 2.2% (95% CI = 1.8% to 2.6%) for low risk, and to 1.8% (95% CI = 1.4% to 2.4%) for noncardiac. The relative risk (RR) of an adverse cardiac event for those with an initial label of unstable angina compared to those with a low-risk designation was 10.2 (95% CI = 8.0 to 13.0). The RR of an event for those with a high-risk initial impression compared to those with a low-risk initial impression was 4.7 (95% CI = 3.8 to 5.9). The risk of an event among those with a low-risk initial impression was the same as for those with a noncardiac initial impression (RR = 0.83, 95% CI = 0.6 to 1.2). Conclusions:In ED patients without obvious initial evidence of a cardiac event, unstructured emergency physician (EP) estimate of risk correlates with adverse cardiac outcomes.ACADEMIC EMERGENCY MEDICINE 2009; 16:740-748 ª

Making the black box more useful

“…Clinicians thought the diagnosis was either ‘definitely not’ or ‘probably not’ ACS, and the ECG showed no ischaemia, and the initial troponin value was normal (assayed either conventionally or with the high sensitivity method) in 106 (23.1%), and none of these patients had the primary outcome and only 1/109 (95% CI 0% to 5%) had a MACE within 30 days. This result is consistent with the findings by Chandra et al 5 and Kline and Stubblefield . 6…”

High-sensitivity versus conventional troponin in the emergency department for the diagnosis of acute myocardial infarction

“…After these routine tests were done, and before cardiac biomarker results were available, ED physicians were asked to offer an 'empirical' clinical probability of AMI (low, medium or high PTP) based on cardiovascular risk factors, type of chest pain, physical findings and electrocardiogram abnormalities [17,18]. Conventional cardiac troponin I (cTnI) was measured at presentation and, if needed, was repeated after 3 to 9 hours as long as it was clinically indicated.…”

When Should Patient Intuition be Taken Seriously?

“…8,9 However, evidence-based medicine also recognizes that clinical expertise, including intuition, is needed to integrate the clinical state and circumstances, research evidence, and patient preferences and actions. 10 Moreover, discrimination between subtle stimuli and integrative processing are central to clinical skills such as ultrasonography 11 and are highly valued [12][13][14] by the patient-centered clinical method, which uses patient experience to help guide clinical interactions and shared decision making. Nevertheless, physicians-unlike nurses 15 -have frequently been reluctant to publicly acknowledge using their own intuition in clinical decision-making; 16 and they have been even quieter in acknowledging their need to take account of patient intuition in decision-making.…”