title: Direct minimally invasive intraoperative electrophysiological mapping of the heart.
abstract: BACKGROUND
  Cardiac electrophysiology aims to describe and treat the electrical activity of the heart. Although an epicardial approach is valuable in many surgical treatments such as coronary artery bypass grafting, maze ablation, and cell transplantation, very few techniques suited for minimally invasive surgery are available for measurement of epicardial electrophysiology.
  
  
  METHODS
  We developed a novel endoscopically-deployable expanding electrode array that can be applied for minimally invasive surgery. Our device consists of a flexible electrode array attached to arms which open and close the electrode sheet. Furthermore, we also developed a computer program to overlay an epicardial electrophysiological map on an endoscopic image. We performed both laboratory and in vivo experiments to examine the feasibility in clinical situations.
  
  
  RESULTS
  Evaluation experiments demonstrated that our novel mapping process that assumes spherical deformation of the electrode array enables us to overlay each electrode position with an accuracy of < 1 mm. Results of animal experiments using large animals (one dog and two pigs) demonstrated that our system enables construction of epicardial electrophysiological maps.
  
  
  CONCLUSIONS
  A novel endoscopically deployable expanding electrode array was developed. Evaluation experiments demonstrated that our device can be manipulated in simulated minimally invasive surgery, and enables construction of epicardial electrophysiological maps.
authors.affiliation: Graduate School of Engineering, the University of Tokyo , Tokyo , Japan.
authors.forename: Takehiro
authors.initials: T
authors.lastname: Ando
authors.forename: Dai
authors.initials: D
authors.lastname: Kawashima
authors.forename: Hongho
authors.initials: H
authors.lastname: Kim
authors.forename: Sanghyun
authors.initials: S
authors.lastname: Joung
authors.forename: Hongen
authors.initials: H
authors.lastname: Liao
authors.forename: Etsuko
authors.initials: E
authors.lastname: Kobayashi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Gojo
authors.forename: Syunei
authors.initials: S
authors.lastname: Kyo
authors.forename: Minoru
authors.initials: M
authors.lastname: Ono
authors.forename: Ichiro
authors.initials: I
authors.lastname: Sakuma
mesh_terms: D000818:Animals; D006348:Cardiac Surgical Procedures / Q000379:methods; D004285:Dogs; D004566:Electrodes; D022062:Electrophysiologic Techniques, Cardiac / Q000379:methods*; D004724:Endoscopy / Q000379:methods*; D056149:Epicardial Mapping / Q000379:methods*; D005240:Feasibility Studies; D019060:Minimally Invasive Surgical Procedures / Q000379:methods*; D010496:Pericardium / Q000502:physiology; D013552:Swine