Which patient populations should receive an automatic Electrocardiogram (EKG) in the Emergency Department (ED)?

Automatic ECG Indications in the Emergency Department

All patients presenting with chest pain or suspected acute coronary syndrome should receive an ECG within 10 minutes of arrival to the ED, regardless of their presenting symptoms or risk factors. 1, 2

Priority Populations for Automatic ECG

1. Patients with chest pain or anginal equivalent symptoms

   • All patients with chest discomfort, pressure, heaviness, or tightness 1
   • Patients with atypical presentations such as:
     • Shortness of breath without chest pain
     • Syncope or near-syncope
     • Acute delirium, especially in patients ≥75 years 2
     • Arm pain, jaw pain, or epigastric discomfort 2

2. High-risk populations

   • Elderly patients (≥75 years) 2
   • Diabetic patients (higher risk of atypical presentation) 2
   • Women (who often present with atypical symptoms and experience delays in ECG acquisition) 3
   • Patients with known coronary artery disease or previous MI 4
   • Patients with multiple cardiovascular risk factors (hypertension, dyslipidemia, smoking, family history) 2

3. Concerning clinical presentations

   • Patients with diaphoresis, tachypnea, or tachycardia 2
   • Patients with rales on examination 4
   • Patients with abnormal vital signs, particularly:
     • Low systolic blood pressure (<110 mmHg)
     • Widened pulse pressure 4
   • Patients with suspected aortic dissection (severe pain, abrupt onset, pulse differential) 2

Implementation Considerations

• ECG should be performed and reviewed within 10 minutes of ED arrival 1
• For patients with initially non-diagnostic ECGs but persistent symptoms or high clinical suspicion, serial ECGs should be performed 1
• Consider supplemental ECG leads (V7-V9) for patients with suspected posterior MI when initial ECG is non-diagnostic 1

Common Pitfalls to Avoid

1. Delayed ECG acquisition in women

   • Studies show significant delays in door-to-ECG times for women (53 minutes vs. 34 minutes for men) 3
   • Only 32% of women vs. 49% of men receive ECGs within the recommended 10-minute window 3

2. Relying solely on typical symptoms

   • Normal initial ECGs can be seen in 20% of AMI patients and 37% of unstable angina patients 4
   • Subtle ECG findings like isolated T-wave inversion in aVL or biphasic T waves may be the only markers of ischemia 5

3. Missing STEMI-equivalents

   • ST depression in leads V1-V3 with tall R waves may indicate posterior infarction 5
   • Diffuse ST depression with elevation in aVR may indicate left main or triple-vessel disease 5

4. Inadequate monitoring after initial ECG

   • Transient ischemic changes may be missed without serial ECGs 1
   • Intermittent reperfusion occurs in 34-40% of acute MI patients, potentially leading to a non-diagnostic initial ECG 1

Evidence Quality and Considerations

The recommendation for universal ECG within 10 minutes for chest pain patients is supported by Class I recommendations from the American College of Cardiology/American Heart Association guidelines 1, 2. This recommendation is primarily based on expert consensus (Level of Evidence C) rather than randomized controlled trials, but is strongly endorsed due to the potential mortality benefit of early identification of STEMI and other life-threatening conditions.

Studies have consistently shown that delays in ECG acquisition are associated with worse outcomes, particularly in women 3. Additionally, the relatively low sensitivity of a single ECG (especially in certain populations) supports the need for serial ECGs when clinical suspicion remains high 1.

Given the high morbidity and mortality associated with missed acute coronary syndromes, and the relatively low cost and risk of ECG testing, the threshold for obtaining an ECG in the ED should be low, with emphasis on rapid acquisition for all patients with possible cardiac symptoms.