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Electrocardiographic demonstration of intermittent left bundle branch block because of the "linking" phenomenon

Okan Erdogan1, Armagan Altun

  • 1Department of Cardiology, School of Medicine, Trakya University, Edirne, Turkey. okanerdogan@yahoo.com

Journal of Electrocardiology
|April 16, 2002
PubMed

Insights

Intermittent left bundle branch block (LBBB) can be perpetuated by a phenomenon called "linking." This occurs when a slow heart rate triggers LBBB, which is then sustained until a premature ventricular contraction resolves it.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Cardiac Electrophysiology

Background:

  • Left bundle branch block (LBBB) is a common cardiac arrhythmia.
  • Understanding the mechanisms of intermittent LBBB is crucial for patient management.

Observation:

  • A patient presented with intermittent left bundle branch block.
  • The LBBB was observed to occur specifically at slower heart rates.

Findings:

  • The study suggests a phenomenon termed "linking" perpetuates LBBB.
  • This linking involves rate-dependent bundle branch block and concealed retrograde conduction.
  • Premature ventricular contractions were noted to resolve the LBBB episodes.

Implications:

  • This case highlights an unusual mechanism for LBBB persistence.
  • Recognizing the "linking" phenomenon can aid in diagnosing and managing intermittent LBBB.
  • Further research into linking may reveal new therapeutic targets for conduction disorders.

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