title: Bio-battery signal predicts myocardial lesion formation and depth in vitro.
abstract: OBJECTIVE
  The aim of this study was to determine if the bio-battery signal can predict myocardial lesion formation and depth.
  
  
  METHODS
  Fresh bovine ventricular myocardium was immersed in a temperature-controlled bath of circulating blood. RF energy was delivered with a custom generator to a catheter electrode. RF energy, electrode temperature, bio-battery signal and tissue impedance were displayed and recorded. A copper return plate was placed in the bath.
  
  
  RESULTS
  When 50 volts of constant RF energy was terminated at a 20, 40, or 60% decline from the maximum bio-battery signal, the lesion depth was 4 +/- 0.4 mm. When RF energy application was terminated later, at a point characterized by a brief change of slope of the bio-battery signal, the lesions measured 7.8 +/- 1.4 mm in depth. This "bump" occurred before a rapid impedance rise.
  
  
  CONCLUSIONS
  The depth of lesions created at the "bump" point was almost two-fold deeper than those at the termination points of 20, 40 and 60% bio-battery decrease (p = 0.0001). When RF energy was terminated at the rapid impedance rise the lesions were similar in depth, 8.2 +/- 0.9 mm, to those obtained when RF energy was stopped at the "bump" (p = 0.28). The bio-battery signal provides a unique marker that might be useful to obtain maximum lesion depth while avoiding rapid impedance rise.
authors.affiliation: University of Arizona, Tucson, USA.
authors.forename: D S
authors.initials: DS
authors.lastname: He
authors.forename: P
authors.initials: P
authors.lastname: Sharma
authors.forename: X
authors.initials: X
authors.lastname: Wang
authors.forename: M
authors.initials: M
authors.lastname: Bosnos
authors.forename: F I
authors.initials: FI
authors.lastname: Marcus
mesh_terms: D000818:Animals; D001145:Arrhythmias, Cardiac / Q000473:pathology / Q000601:surgery; D017115:Catheter Ablation / Q000295:instrumentation*; D002417:Cattle; D017097:Electric Impedance; D006352:Heart Ventricles / Q000473:pathology / Q000601:surgery*; D066298:In Vitro Techniques; D013696:Temperature