title: High resolution optical mapping of cardiac action potentials in freely beating rabbit hearts.
abstract: Optical mapping of action potentials (APs) has become important tools for the cardiac electrophysiology. However, cardiac contraction unavoidably produces motion artifacts (MA) in optical signal. We developed a method to suppress motion artifacts without arresting the hearts.
  
  
  METHODS
  Using a dual-wavelength optical mapping system, APs were recorded on the surface of an isolated rabbit heart. Transmembrane APs were simultaneously recorded using glass microelectrodes. We eliminated MA in a frontal plane by a motion tracking technique. Subsequently, a dual-wavelength ratiometric method was used to remove MA in a vertical direction to a frontal plane.
  
  
  RESULTS
  MA were effectively removed from optical signals. Action potential duration measured from optical signals corresponded with those measured from microelectrodes (r2=0.9677). Our method enables us to map action potentials in freely beating hearts.
authors.affiliation: Department of Cardiovascular Dynamics, National Cardiovascular Center Research Institute, Suita, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Inagaki
authors.forename: I
authors.initials: I
authors.lastname: Hidaka
authors.forename: T
authors.initials: T
authors.lastname: Aiba
authors.forename: T
authors.initials: T
authors.lastname: Tatewaki
authors.forename: K
authors.initials: K
authors.lastname: Sunagawa
authors.forename: M
authors.initials: M
authors.lastname: Sugimachi