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Atrioventricular node fetal dispersion and His bundle fragmentation of the cardiac conduction system in sudden

M P Suarez-Mier1, C Gamallo

  • 1Section of Histopathology, Institute of Toxicology, Madrid, Spain. histop@mad.inaltox.es

Journal of the American College of Cardiology
|December 19, 1998
PubMed

Insights

Persistent fetal dispersion of the atrioventricular (AV) node and His bundle fragmentation are common findings. These cardiac conduction system variations are more frequent in controls and not necessarily linked to sudden cardiac death.

Area of Science:

  • Cardiovascular Pathology
  • Cardiac Electrophysiology
  • Forensic Medicine

Background:

  • Persistent fetal dispersion of the atrioventricular (AV) node and His bundle fragmentation are frequently reported in sudden cardiac death cases.
  • These findings are among the most common lesions identified in the cardiac conduction system.

Purpose of the Study:

  • To determine the frequency of persistent fetal dispersion of the AV node and His bundle fragmentation.
  • To evaluate the significance of these findings in sudden cardiac death cases compared to controls.

Main Methods:

  • Analysis of the cardiac conduction system in 347 hearts (249 sudden cardiac death cases, 98 controls).
  • Categorization of sudden cardiac death cases into ischemic heart disease, non-ischemic heart disease, and unexplained sudden cardiac death groups.

Main Results:

  • Persistent fetal dispersion of the AV node found in 20.17% of all hearts, significantly higher in controls (40.81%).
  • His bundle fragmentation observed in 31.77% of all hearts, also significantly higher in controls (47.67%).

Conclusions:

  • Persistent fetal dispersion of the AV node and His bundle fragmentation can represent normal variations.
  • These anatomical findings should not be presumed as the cause of arrhythmias or sudden death without supporting electrocardiographic abnormalities.
Abstract

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