title: [Potential distribution of electrocardiac field around chick embryonic heart].
abstract: OBJECTIVE
  To explore the essential features of the potential distribution of electrocardiac field.
  
  
  METHODS
  The ECGs of 60 hearts of 5-day chick embryos were immersed in normal saline solution or distilled water and their different conductivities were recorded at 5 points at different distances in 4 directions perpendicular to each other. Comparison of the form and amplitude of ECGs was made between every two points with the same distance to the heart in 2 opposite directions to determine the potential distribution of the electrocardiac field of the one-chambered heart.
  
  
  RESULTS
  The ECGs recorded at every 2 points in 2 opposite directions with the same distance to the heart immersed in the same liquid medium were both upper standing, with no significant different between their amplitude of R(r) wave (P > 0.05).
  
  
  CONCLUSIONS
  The uniform outward potential distribution of the electrocardiac field might not represent the form of depolarization but that of sphere-like and single-source when the influence of different reference points and thickness of different chamber walls upon mapping of body surface is excluded.
authors.affiliation: Center of Medical Experiment Teaching, Basic Medicine College, Southern Medical University, Guangzhou, 510515, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhou
mesh_terms: D000200:Action Potentials; D000818:Animals; D002642:Chick Embryo; D004562:Electrocardiography; D006321:Heart / Q000196:embryology*; D066298:In Vitro Techniques