title: Validation of a new noncontact catheter system for electroanatomic mapping of left ventricular endocardium.
abstract: BACKGROUND
  Improvements in cardiac mapping are required to advance our understanding and treatment of arrhythmias. This study validated a new noncontact multielectrode array catheter and accompanying analysis system to provide electroanatomic mapping of the entire left ventricular (LV) endocardium during a single beat.
  
  
  RESULTS
  A 9F 64-electrode balloon array catheter with an inflated size of 1.8x4.6 cm was used to simultaneously record electrical potentials generated by the heart and locate a standard electrophysiology (EP) catheter within the same chamber. By use of the recorded location of the EP-catheter tip, LV geometry was determined. Array potentials served as inputs to a high-order boundary-element method to produce 3360 potential points on the endocardial surface translatable into electrograms or color-coded activation maps. Three methods of validation were used: (1) driven electrodes in an in vitro tank were located; (2) waveforms generated from the array catheter were compared with catheter contact waveforms in canine LV; and (3) sites of local LV endocardial activation were located and marked with radiofrequency lesions. Tank testing located a driven electrode to within 2.33+/-0.44 mm. Correlation of timing and morphology of computed versus contact electrograms was 0.966. Radiofrequency lesions marked 17 endocardial pacing sites to within 4.0+/-3.2 mm.
  
  
  CONCLUSIONS
  This new system provides anatomically accurate endocardial isopotential mapping during a single cardiac cycle. The locator component enabled placement of a separate EP catheter to any site within the mapped chamber.
authors.affiliation: University of Minnesota, Veterans Affairs Medical Center, Minneapolis, Minn. 55417, USA. gorni002@maroon.tc.umn.edu
authors.forename: C C
authors.initials: CC
authors.lastname: Gornick
authors.forename: S W
authors.initials: SW
authors.lastname: Adler
authors.forename: B
authors.initials: B
authors.lastname: Pederson
authors.forename: J
authors.initials: J
authors.lastname: Hauck
authors.forename: J
authors.initials: J
authors.lastname: Budd
authors.forename: J
authors.initials: J
authors.lastname: Schweitzer
mesh_terms: D000818:Animals; D001145:Arrhythmias, Cardiac / Q000503:physiopathology / Q000601:surgery*; D006328:Cardiac Catheterization; D017115:Catheter Ablation; D002404:Catheterization; D003198:Computer Simulation; D004285:Dogs; D004562:Electrocardiography; D004566:Electrodes; D004594:Electrophysiology / Q000295:instrumentation* / Q000379:methods* / Q000592:standards; D004699:Endocardium / Q000502:physiology*; D004867:Equipment Design; D006329:Heart Conduction System / Q000502:physiology; D008955:Models, Cardiovascular; D010138:Pacemaker, Artificial; D010210:Papillary Muscles / Q000502:physiology; D011690:Purkinje Fibers / Q000502:physiology; D015203:Reproducibility of Results; D016277:Ventricular Function, Left / Q000502:physiology*