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Discrepancy between electrical and mechanical dyssynchrony in patients with heart failure and an electrical

Ryudo Fujiwara1, Akihiro Yoshida, Koji Fukuzawa

  • 1Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan.

Pacing and Clinical Electrophysiology : PACE
|December 31, 2013
PubMed

Insights

A mismatch between electrical and mechanical dyssynchrony in heart failure patients may hinder effective left ventricular lead placement for cardiac resynchronization therapy (CRT). Optimizing CRT response requires considering both electrical and mechanical factors.

Area of Science:

  • Cardiology
  • Biomedical Engineering
  • Electrophysiology

Background:

  • Cardiac resynchronization therapy (CRT) enhances survival in heart failure patients.
  • A significant portion of patients (30-40%) do not respond to CRT.
  • Left ventricular (LV) lead positioning is a key factor influencing CRT response.

Purpose of the Study:

  • To investigate the relationship between electrical and mechanical activation of the left ventricle.
  • To compare electrical and mechanical dyssynchrony in patients undergoing CRT.
  • To determine if discrepancies in dyssynchrony affect CRT outcomes.

Main Methods:

  • Constructed electroanatomical contact maps using EnSite NavX™ in 16 patients during CRT implantation.
  • Evaluated mechanical activation using speckle-tracking echocardiography.
  • Compared the latest electrical and mechanical activation sites and delays of the LV lead.

Main Results:

  • The latest electrical and mechanical activation sites coincided in only 3 out of 16 patients.
  • A significantly greater local mechanical delay was observed in CRT responders compared to non-responders.
  • No significant difference in local electrical delay was found between responders and non-responders.

Conclusions:

  • A discrepancy between electrical and mechanical dyssynchrony may impede optimal LV lead positioning.
  • Understanding this discrepancy is crucial for improving CRT efficacy.
  • Further research is needed to optimize LV lead placement based on both electrical and mechanical assessments.
Abstract

Keywords:
cardiac resynchronization therapydyssynchronyelectrical delaymechanical delay

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