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Electrocardiographic manifestations: bundle branch blocks and fascicular blocks

Richard A Harrigan1, Marc L Pollack, Theodore C Chan

  • 1Department of Emergency Medicine, Temple University Hospital, Jones Hall 10th Floor, Ontario Street & Park Avenue, Philadelphia, PA 19140, USA

The Journal of Emergency Medicine
|July 17, 2003
PubMed

Insights

Intraventricular conduction blocks involve delayed ventricular activation, identified by QRS complex and ST-T changes on ECGs. Recognizing causes like bundle branch or fascicular blocks is clinically important.

Area of Science:

  • Cardiology
  • Electrophysiology

Background:

  • Intraventricular conduction blocks encompass various electrocardiographic conditions characterized by delayed ventricular activation.
  • These blocks are diagnosed through analysis of the QRS complex and associated ST-T wave changes.

Observation:

  • Key examples include right bundle branch block, left bundle branch block, and fascicular blocks (left anterior and left posterior).
  • The etiology of these blocks can be cardiac or noncardiac.

Findings:

  • This review details the electrocardiographic definitions of different intraventricular conduction blocks.
  • It also explores the clinical correlations and significance of recognizing their underlying causes.

Implications:

  • Accurate identification of intraventricular conduction blocks and their causes is crucial for effective clinical management.
  • Understanding these ECG findings aids in diagnosing and treating various heart conditions.

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