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High-Resolution Endocardial and Epicardial Optical Mapping in a Sheep Model of Stretch-Induced Atrial Fibrillation
09:17

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Epicardial organization of human ventricular fibrillation

Kumaraswamy Nanthakumar1, Gregory P Walcott, Sharon Melnick

  • 1Division of Cardiovascular Medicine, University of Alabama at Birmingham, 35294, USA. kn@crml.uab.edu

Heart Rhythm
|April 27, 2005
PubMed

Insights

Human ventricular fibrillation (VF) involves large, organized wavefronts, not chaotic ones. This study reveals significant organization in VF, challenging previous hypotheses about its chaotic nature.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Cardiac Surgery

Background:

  • Ventricular fibrillation (VF) is a major cause of cardiovascular mortality.
  • The precise nature of VF wavefronts in humans remains poorly understood.

Purpose of the Study:

  • To investigate the characteristics of ventricular fibrillation (VF) wavefronts on the human epicardium.
  • To test the hypothesis that human VF comprises chaotic, small wavefronts with constantly changing paths.

Main Methods:

  • Recorded VF from 504 electrodes on the anterior left ventricle epicardium in 9 cardiac surgery patients.
  • Analyzed 26 two-second segments of VF using a computer algorithm to identify and classify wavefronts.
  • Assessed wavefront pathways, size, and reentry events during VF episodes.

Main Results:

  • VF wavefronts were predominantly large and followed distinct, repeating pathways.
  • Reentry events were infrequent, occurring in only 62% of analyzed segments and lasting for a small percentage of the total duration.
  • The findings suggest a higher degree of organization in human VF than previously hypothesized.

Conclusions:

  • Human epicardial VF wavefronts are typically large and organized, not small and chaotic.
  • The study's findings challenge the hypothesis of chaotic VF and indicate significant underlying organization.
  • These insights into VF wavefront dynamics may inform future therapeutic strategies.
Abstract

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