Testing of Low-Risk Patients Presenting to the Emergency Department With Chest Pain

Abstract

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.

A comparison of coronary CTA and stress testing using high-efficiency SPECT MPI for the evaluation of chest pain in the emergency department

“…1 As overcrowded emergency departments continue to see millions of patients each year with chest pain, chest pain units (CPU) have been established to efficiently and accurately identify patients with cardiac ischemia and rapidly exclude those without it. 2 Noninvasive cardiac diagnostic testing has become a cornerstone of the evaluation and triage of these ED CPU patients.…”

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

“…32 This editorial appears to oppose the recommendations of the 2010 AHA scientific statement that supports expedited management of low-risk ED chest pain patients by combining clinical assessment with a confirmatory diagnostic test to exclude ischemia as "safe, accurate and cost-effective". 10 Our study suggests that it would be unwise to discharge low to intermediate risk ED patients on the basis of risk factors and scores without confirmatory testing, as cCTA did identify a small percentage of patients with significant CAD (17/250 = 6.8%) and 30 day adverse events (6/221 = 2.7%) who might not otherwise be detected based upon clinical presentation to the ED. It is also unlikely that our ED physicians would be willing to discharge low to intermediate risk patients when missed CAD/ACS and subsequent heart attacks account for 20-39% of all ED malpractice judgments.…”

“…9 A scientific statement of the American Heart Association (AHA) supports expedited management of low-risk chest pain patients by combining clinical and laboratory assessments with a confirmatory stress test as "safe, accurate and cost-effective". 10 Conventional standard of care for ED chest pain patients results in a documented miss rate of 2-5% for acute coronary syndrome (ACS). 11,12 Missed ACS and subsequent heart attacks account for 20-39% of all ED malpractice judgments.…”

Acute chest pain of uncertain etiology, the short and long view

“…Pre-discharge exercise testing has therefore become an essential component of the evaluation protocol in CPCs. 7 This is particularly useful because exercise capacity is a strong independent predictor of cardiovascular outcomes, regardless of the presence of CAD. 8 Patients who cannot achieve 6 METs during exercise testing have a high ([60%) 4-year cardiac mortality rate, whereas patients who exercise [10 METs have a very low (\0.5%) cardiac event rate.…”