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Accessory Cardiac Conduction Pathway with an Unusual Presentation.

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Pre-excitation syndrome (PES) can rarely present with complete heart block (CHB), not just tachycardia. This case highlights the need for careful evaluation of syncope in PES patients, leading to pacemaker implantation instead of ablation.

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Area of Science:

  • Cardiology
  • Electrophysiology
  • Congenital Heart Abnormalities

Background:

  • Pre-excitation syndrome (PES) involves accessory pathways causing early ventricular excitation.
  • Wolf-Parkinson-White (WPW) syndrome is the most common form of PES.
  • PES typically predisposes individuals to supra-ventricular tachycardias like atrioventricular reciprocating tachycardia (AVRT).

Observation:

  • A 37-year-old male presented with syncope and ECG findings consistent with PES.
  • ECG monitoring revealed complete heart block (CHB) with intermittent accessory pathway conduction.
  • Syncope in PES patients often suggests tachyarrhythmias, but bradyarrhythmias like CHB are a rare possibility.

Findings:

  • The patient exhibited a rare association of PES with CHB.
  • Intermittent conduction through the accessory pathway was observed alongside CHB.
  • This presentation diverged from the typical tachyarrhythmic complications of PES.

Implications:

  • Syncope in PES patients necessitates a thorough diagnostic evaluation beyond just tachyarrhythmias.
  • Management strategies for PES with CHB differ significantly from standard PES treatment.
  • Dual-chamber pacemaker implantation was the chosen therapeutic approach, differing from accessory pathway ablation.