Can Wolff-Parkinson-White (WPW) syndrome exhibit symptoms similar to Postural Orthostatic Tachycardia Syndrome (POTS)?

Can WPW Syndrome Present with Symptoms Similar to POTS?

Yes, Wolff-Parkinson-White (WPW) syndrome can present with symptoms that mimic Postural Orthostatic Tachycardia Syndrome (POTS), particularly palpitations, light-headedness, and syncope upon standing, though the underlying mechanisms differ significantly.

Symptom Overlap Between WPW and POTS

Common Symptoms in Both Conditions

• Palpitations: Both conditions can cause awareness of rapid heartbeat
• Light-headedness/dizziness: Especially upon standing or with exertion
• Near-syncope or syncope: Though true syncope is more common in WPW than in POTS
• Exercise intolerance: Patients with either condition may experience limitations during physical activity
• Fatigue: Can be present in both conditions

Key Differences in Presentation

1. Postural Component:

   • POTS: Defined by orthostatic HR increase (≥30 bpm or to ≥120 bpm within 10 min of standing) without significant BP drop 1
   • WPW: Symptoms can occur at rest, during exercise, or with emotional stress, not specifically tied to postural changes

2. Tachycardia Pattern:

   • POTS: Persistent sinus tachycardia upon standing
   • WPW: Paroxysmal supraventricular tachycardia (PSVT) or atrial fibrillation with rapid ventricular response 1

Diagnostic Differentiation

ECG Findings

• WPW: Characteristic findings include:

  • Short PR interval
  • Delta wave (slurred upstroke of QRS)
  • Widened QRS complex
  • Possible pseudo-infarct patterns 1

• POTS: Normal ECG at rest with appropriate sinus tachycardia upon standing

Clinical Evaluation

The 2015 ACC/AHA/HRS SVT Guidelines specifically note that POTS is a "confounding factor in diagnosing SVT" and must be differentiated from conditions like WPW syndrome 1. This highlights that clinicians must be vigilant about distinguishing between these conditions.

Clinical Implications and Management

WPW Management

• Risk assessment: Evaluate for risk of sudden cardiac death (SCD), which occurs at a rate of 0.15-0.39% over 3-10 years 1
• High-risk features: Short refractory period (<250ms), multiple accessory pathways, history of pre-excited atrial fibrillation 2
• Treatment: Catheter ablation is first-line therapy for symptomatic patients, with success rates exceeding 95% 2

POTS Management

• Conservative measures: Increased fluid/salt intake, compression garments, exercise reconditioning
• Medications: Beta-blockers, fludrocortisone, midodrine

Important Cautions

1. Medication considerations:

   • AV nodal blocking agents (including beta-blockers commonly used in POTS) are contraindicated in WPW with atrial fibrillation as they can accelerate ventricular rate and potentially precipitate ventricular fibrillation 2

2. Misdiagnosis risks:

   • Treating presumed POTS with AV nodal blockers when the patient actually has WPW could be dangerous
   • Comprehensive evaluation including ECG is essential before initiating treatment

Clinical Pearls

• In young patients presenting with orthostatic symptoms and tachycardia, obtain a 12-lead ECG to evaluate for WPW pattern before diagnosing POTS
• The 2015 ACC/AHA/HRS guidelines note that WPW syndrome can present with syncope in 4% of cases 1
• WPW can be associated with other cardiac conditions like Ebstein's anomaly, which increases risk 2
• Consider WPW particularly in patients whose symptoms are paroxysmal rather than consistently related to posture

When evaluating patients with orthostatic symptoms and tachycardia, thorough ECG assessment is essential to distinguish between these conditions and ensure appropriate management strategies.