What is the initial workup for a patient presenting with palpitations?

Initial Workup for Patients with Palpitations

The initial workup for a patient presenting with palpitations should include a 12-lead ECG, basic laboratory tests, and cardiac monitoring, with the specific type of monitoring determined by the frequency of symptoms. 1

Initial Evaluation

History

• Obtain detailed information about:
  • Position when palpitations occur (supine, sitting, standing) 2
  • Activity during episodes (rest, posture change, during/after exercise, during/after urination or defecation) 2
  • Predisposing factors (crowded places, warm environments, prolonged standing, post-meal) 2
  • Precipitating events (fear, pain, neck movements) 2
  • Onset characteristics (nausea, vomiting, sweating, aura, neck pain) 2
  • Associated symptoms (syncope, near-syncope, dyspnea, chest pain) 2
  • Temporal relationship between symptoms and potential triggers 1

Physical Examination

• Assess for:
  • Signs of structural heart disease
  • Irregular cannon A waves or irregular S1 intensity (suggests ventricular origin) 2
  • Thyroid abnormalities

Initial Testing

1. 12-lead ECG (Class I, Level B-NR) 1, 2

   • Essential even if patient is not currently experiencing symptoms
   • May reveal pre-excitation patterns requiring referral to electrophysiologist 2
   • Identifies baseline cardiac abnormalities

2. Basic laboratory tests (Class I) 2, 1

   • Complete blood count
   • Electrolytes
   • Thyroid function tests
   • Consider additional tests based on clinical suspicion

Cardiac Monitoring

The type of monitoring depends on symptom frequency:

1. For frequent symptoms (several episodes per week):

   • 24-48 hour Holter monitoring (Class I, Level B-NR) 2, 1

2. For less frequent but recurrent symptoms:

   • Event recorder or mobile cardiac telemetry for 2-4 weeks 1
   • Wearable loop recorder 2

3. For rare symptoms (fewer than two episodes per month):

   • Implantable loop recorder may be considered 2

Additional Testing Based on Initial Findings

For Patients with Suspected Heart Disease

• Echocardiography (Class I) 2
  • To exclude structural heart disease
  • Particularly important for patients with sustained SVT

For Specific Symptom Patterns

• Extended monitoring (>24 hours) for patients with palpitations and lightheadedness (Class I, Level B-NR) 2
• Exercise stress testing for patients with palpitations during or after effort 2

For Patients with Pre-excitation on ECG

• Immediate electrophysiological evaluation is required, especially if irregular palpitations suggest AF (high risk for sudden death) 2

Special Considerations

Red Flags Requiring Urgent Evaluation

• Palpitations with syncope or near-syncope
• Family history of sudden cardiac death
• Pre-excitation on ECG
• Known structural heart disease
• Palpitations during exercise

Common Pitfalls to Avoid

1. Attributing all symptoms to anxiety without adequate cardiac evaluation 1
2. Relying solely on short-term monitoring for infrequent symptoms 1
3. Overlooking medication side effects 1
4. Dismissing patient symptoms despite normal initial testing 1
5. Failing to recognize that many patients with arrhythmias do not experience palpitations 3

Referral Indications

Refer to a cardiac arrhythmia specialist for:

• Wide complex tachycardia of unknown origin 2
• Narrow complex tachycardias with drug resistance or intolerance 2
• All patients with Wolff-Parkinson-White syndrome 2
• Severe symptoms (syncope, dyspnea) during palpitations 2

By following this systematic approach to evaluating palpitations, clinicians can efficiently identify the underlying cause and determine appropriate management strategies while avoiding unnecessary testing.