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Profound independent effects of left bundle branch block and heart rate during supraventricular tachycardia

John D Fisher1

  • 1Department of Medicine, Cardiology Division, Arrhythmia Service, Montefiore Medical Center and the Albert Einstein College of Medicine, Cardiology-N2-Silver Zone, NY 10467, USA. jfisher@montefiore.org

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

Insights

Left bundle branch block (LBBB) significantly worsens hypotension during supraventricular tachycardia. This effect is rate-dependent, with blood pressure similar at slower rates, regardless of LBBB presence.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Hemodynamics

Background:

  • Left bundle branch block (LBBB) is known to have adverse hemodynamic consequences.
  • Supraventricular tachycardia (SVT) can precipitate hemodynamic instability.

Observation:

  • In patients with LBBB, profound hypotension was observed during SVT.
  • This hypotension was not present at the same SVT rate in the absence of LBBB.
  • At slower heart rates, blood pressure remained similar whether LBBB was present or not.

Findings:

  • LBBB exacerbates the blood pressure drop during SVT.
  • The hemodynamic impact of LBBB during SVT is rate-dependent.

Implications:

  • Understanding this interaction is crucial for managing patients with LBBB and SVT.
  • This highlights the importance of considering LBBB in the assessment of hypotension during tachyarrhythmias.

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