When should I add an electrocardiogram (EKG) for interpretation?

When to Add an Electrocardiogram (EKG) for Interpretation

An EKG should be obtained in patients with known cardiovascular disease, those presenting with cardiac symptoms (chest pain, syncope, palpitations, dyspnea), before and after cardiovascular procedures, when monitoring medication effects, and in patients with implanted cardiac devices. 1

Specific Clinical Indications

Patients with Known Cardiovascular Disease

• Initial evaluation of all patients with diagnosed heart disease
• When symptoms change or worsen
• To assess response to therapy when treatment is expected to produce ECG changes
• For monitoring progression or regression of disease
• Before cardiac or non-cardiac surgery 2

Symptomatic Patients

• Patients presenting with:
  • Chest pain or discomfort
  • Syncope or near-syncope
  • Unexplained changes in angina pattern
  • New or worsening dyspnea
  • Extreme fatigue, weakness, or prostration
  • Palpitations 2

Medication Monitoring

• After initiation of drugs known to cause ECG changes:
  • Psychotropic agents (phenothiazines, tricyclic antidepressants, lithium)
  • Anti-infective agents (erythromycin, pentamidine)
  • Antihypertensive medications
  • Antineoplastic agents
  • Heart failure medications (digitalis, dopamine, dobutamine)
• When changing dosage of these medications
• When adding potentially interacting medications 2

Procedural Indications

• Before and immediately after cardioversion procedures
• Before and after cardiac catheterization or angioplasty
• After pacemaker insertion or revision
• After cardiac surgery until condition stabilizes
• Before hospital discharge following cardiac procedures 2

Device Monitoring

• After pacemaker or defibrillator implantation
• When device malfunction is suspected
• At periodic intervals throughout the lifetime of patients with implanted devices
• More frequent monitoring for atrial or dual-chamber pacing systems 2

Special Considerations

Acute Coronary Syndromes

• Obtain ECG as soon as possible in patients with suspected ACS
• Serial ECGs may be necessary in evolving conditions
• ECG should be interpreted in conjunction with clinical signs and cardiac biomarkers
• Remember that a normal ECG does not rule out ACS - 1-4% of patients with normal ECGs may still have AMI 3, 2

Interpretation Requirements

• ECG interpretation requires qualified physician review
• Computer interpretation alone is insufficient and potentially dangerous
• Comparison with previous ECGs is valuable when available 1

Pitfalls to Avoid

• Over-reliance on a normal ECG in a patient with classic anginal symptoms
• Failure to obtain serial ECGs in evolving conditions
• Assuming computer interpretation is always accurate
• Neglecting to obtain ECGs after medication changes that could affect cardiac conduction
• Forgetting that many non-cardiac conditions can cause ECG abnormalities 3

By following these guidelines, you can ensure appropriate use of ECGs in clinical practice, improving patient outcomes while avoiding unnecessary testing.