title: Simultaneous assessment of contact pressure and local electrical coupling index using robotic navigation.
abstract: OBJECTIVE
  Contact with cardiac tissue is a determinant of lesion efficacy during atrial fibrillation (AF) ablation. The Sensei®X Robotic Catheter System (Hansen Medical, CA) has been validated for contact force sensing. The electrical coupling index (ECI) from the EnSite Contact™ system (St. Jude Medical, MN) has been validated as an indicator of tissue contact. We aimed at analyzing ECI behavior during radiofrequency (RF) pulses maintaining a stable contact through the robotic navigation contact system.
  
  
  METHODS
  In 15 patients (age, 59 ± 12) undergoing AF ablation, pulmonary vein (PV) isolation was guided by the Sensei®X System, employing the Contact™ catheter.
  
  
  RESULTS
  During the procedure, we assessed ECI changes associated with adequate contact based on the IntelliSense® force-sensing technology (Hansen Medical, CA. Baseline contact (27 ± 8 g/cm(2)) ECI value was 99 ± 13, whereas ECI values in a noncontact site (0 g/cm(2)) and in a light contact site (1-10 g/cm(2)) were respectively 66 ± 12 and 77 ± 10 (p < 0.0001). Baseline contact ECI values were not different depending on AF presentation (paroxysmal AF, 98 ± 9; persistent AF, 100 ± 9) or on cardiac rhythm (sinus rhythm, 97 ± 7; AF,101 ± 10). In all PVs, ECI was significantly reduced during and after ablation (ECI during RF, 56 ± 15; ECI after RF, 72 ± 16; p < 0.001). A mean reduction of 32.2% during RF delivery and 25.4% immediately after RF discontinuation compared with baseline ECI was observed.
  
  
  CONCLUSIONS
  Successful PV isolation is associated with a significant decrease in ECI of at least 20 %. This may be used as a surrogate marker of effective lesion in AF ablation.
authors.affiliation: Cardiac Arrhythmia Research Centre, Centro Cardiologico Monzino IRCCS, Via Parea 4, 20138, Milan, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Dello Russo
authors.forename: Gaetano
authors.initials: G
authors.lastname: Fassini
authors.forename: Michela
authors.initials: M
authors.lastname: Casella
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Bologna
authors.forename: Osama
authors.initials: O
authors.lastname: Al-Nono
authors.forename: Daniele
authors.initials: D
authors.lastname: Colombo
authors.forename: Viviana
authors.initials: V
authors.lastname: Biagioli
authors.forename: Pasquale
authors.initials: P
authors.lastname: Santangeli
authors.forename: Luigi
authors.initials: L
authors.lastname: Di Biase
authors.forename: Martina
authors.initials: M
authors.lastname: Zucchetti
authors.forename: Benedetta
authors.initials: B
authors.lastname: Majocchi
authors.forename: Vittoria
authors.initials: V
authors.lastname: Marino
authors.forename: Joseph J
authors.initials: JJ
authors.lastname: Gallinghouse
authors.forename: Andrea
authors.initials: A
authors.lastname: Natale
authors.forename: Claudio
authors.initials: C
authors.lastname: Tondo
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000601:surgery*; D017115:Catheter Ablation / Q000295:instrumentation / Q000379:methods*; D017097:Electric Impedance; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010992:Plethysmography, Impedance / Q000379:methods; D011312:Pressure; D012371:Robotics; D025321:Surgery, Computer-Assisted