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Pulsus alternans caused by 2:1 left bundle branch block

S Serge Barold1, Bengt Herweg

  • 1Division of Cardiology, University of South Florida College of Medicine and Tampa General Hospital, USA. ssbarold@aol.com

Journal of Interventional Cardiac Electrophysiology : an International Journal of Arrhythmias and Pacing
|May 6, 2005
PubMed

Insights

Pulsus alternans, a pulse irregularity, resulted from a complete left bundle branch block. This condition significantly impacted heart function even with preserved ejection fraction.

Area of Science:

  • Cardiology
  • Cardiac Electrophysiology
  • Heart Failure Research

Background:

  • Pulsus alternans is an irregular pulse characterized by alternating strong and weak beats.
  • Left bundle branch block (LBBB) can affect cardiac function and hemodynamics.
  • Understanding the interplay between LBBB and ventricular function is crucial for managing heart conditions.

Observation:

  • A case study identified a 2:1 left bundle branch block as the cause of pulsus alternans.
  • The patient presented with a left ventricular ejection fraction of 50% and normal coronary arteries.
  • Hemodynamic monitoring revealed significant cardiac depression.

Findings:

  • Complete left bundle branch block was directly linked to the development of pulsus alternans.
  • The hemodynamic effects of LBBB were profound, even in the presence of a preserved left ventricular ejection fraction (50%).
  • This suggests LBBB can significantly impair systolic function.

Implications:

  • The findings highlight the critical role of the His-Purkinje system in maintaining coordinated ventricular contraction.
  • This case underscores the potential for LBBB to cause significant hemodynamic compromise.
  • Further research into LBBB's impact on systolic function is warranted, particularly in patients with preserved ejection fraction.

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