When should a patient go to the Emergency Room (ER) based on their Electrocardiogram (EKG) results?

When to Go to the ER Based on EKG Results

Patients should immediately go to the Emergency Room when their EKG shows ST-segment elevation, ST-segment depression, new T-wave inversions, new left bundle branch block, or when they have concerning symptoms even with a normal EKG. 1

Urgent EKG Findings Requiring Immediate ER Visit

ST-Segment Changes

• ST-segment elevation: Indicates potential STEMI (ST-elevation myocardial infarction) - requires immediate ER evaluation
• ST-segment depression: Suggests NSTEMI (non-ST-elevation myocardial infarction) or unstable angina - requires immediate ER evaluation
• Diffuse ST-segment elevation: May indicate pericarditis - requires prompt evaluation

Other Critical EKG Findings

• New left bundle branch block
• New T-wave inversions
• New arrhythmias (especially ventricular arrhythmias)
• Posterior MI patterns (may require additional leads V7-V9 to detect)

Symptoms Requiring ER Visit Regardless of EKG

Even with a normal or nonspecific EKG, patients should go to the ER if they experience:

• Chest pain or discomfort with characteristics suggesting ischemia:
  • Central/retrosternal location
  • Pressure, heaviness, tightness, squeezing sensation
  • Radiation to left arm, jaw, or back
  • Associated with exertion or stress 1
• Chest pain accompanied by:
  • Shortness of breath
  • Diaphoresis (sweating)
  • Nausea/vomiting
  • Lightheadedness/dizziness
  • Syncope (fainting)

Special Considerations

For Women

Women may present with less typical symptoms and are at higher risk for underdiagnosis. Women should go to the ER when experiencing:

• Unusual fatigue
• Shortness of breath
• Upper back, shoulder, or jaw pain
• Nausea/vomiting without chest pain 1

For Older Adults (≥75 years)

Older adults should go to the ER when experiencing:

• Shortness of breath
• Syncope
• Acute delirium
• Unexplained falls
• Any chest discomfort, even if atypical 1

Important Caveats

1. A normal EKG does not rule out ACS: Studies show that up to 6% of patients with evolving ACS are discharged from the ED with a normal EKG 1. A normal EKG during symptoms does not lower the risk of ACS compared to when asymptomatic 2.

2. Serial EKGs may be necessary: If an initial EKG is normal but symptoms persist or worsen, repeat EKGs should be performed to detect evolving changes 1.

3. Specific patient populations: Certain groups (women under 55, non-white patients, those presenting with shortness of breath as chief complaint) are at higher risk for missed diagnosis 3.

4. Non-cardiac causes with EKG changes: Conditions like pneumothorax can cause EKG changes that may mimic cardiac issues 4. However, these still warrant emergency evaluation.

Decision Algorithm

1. Go to ER immediately if:

   • Any ST-segment changes (elevation or depression)
   • New T-wave inversions
   • New left bundle branch block
   • New arrhythmias
   • Chest pain with high-risk features (as described above)
   • Any concerning symptoms in high-risk populations (women, elderly)

2. Go to ER within 10 minutes of symptom onset if:

   • Chest pain or discomfort of any kind that could represent ACS
   • Normal EKG but persistent symptoms

3. Call emergency services (EMS) rather than self-transport when any of the above are present, as EMS can:

   • Acquire prehospital ECG
   • Provide treatment en route
   • Implement defibrillation if needed
   • Facilitate faster hospital arrival 1

Remember that delaying evaluation for chest pain can have serious consequences. When in doubt about an EKG finding, seeking emergency care is the safest approach.