title: Electromagnetic Contact-Force Sensing Electrophysiological Catheters: How Accurate is the Technology?
abstract: BACKGROUND
  Contact-force (CF) sensing catheters are increasingly used in clinical electrophysiological practice due to their efficacy and safety profile. As data about the accuracy of this technology are scarce, we sought to quantify accuracy based on in vitro experiments.
  
  
  RESULTS
  A custom-made force sensor was constructed that allowed exact force reference measurements registered via a flexible membrane. A Smarttouch Surround Flow (ST SF) ablation catheter (Biosense Webster, Diamond Bar, CA, USA) was brought in contact with the membrane of the force sensor in order to compare the ST SF force measurements to force sensor reference measurements. ST SF force sensing technology is based on deflection registration between the distal and proximal catheter tip. The experiment was repeated for n = 10 ST SF catheters, which showed no significant difference in accuracy levels. A series of measurements (n = 1200) was carried out for different angles of force acting to the catheter tip (0°/perpendicular contact, 30°, 60°, 90°/parallel contact). The mean absolute differences between reference and ST SF measurements were 1.7 ± 1.8 g (0°), 1.6 ± 1.2 g (30°), 1.4 ± 1.3 g (60°), and 6.6 ± 5.9 g (90°). Measurement accuracy was significantly higher in non-parallel contact when compared with parallel contact (P < 0.01).
  
  
  CONCLUSIONS
  Catheter force measurements using the ST SF catheters show a high level of accuracy regarding differences to reference measurements and reproducibility. The reduced accuracy in measurements of 90° acting forces (parallel contact) might be clinically important when creating, for example, linear lesions.
authors.affiliation: Department of Electrophysiology, German Heart Center Munich, Technische Universitaet Munich, Germany.
authors.forename: Felix
authors.initials: F
authors.lastname: Bourier
authors.affiliation: Department of Electrophysiology, German Heart Center Munich, Technische Universitaet Munich, Germany.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Hessling
authors.affiliation: Department of Electrophysiology, German Heart Center Munich, Technische Universitaet Munich, Germany.
authors.forename: Sonia
authors.initials: S
authors.lastname: Ammar-Busch
authors.affiliation: Department of Electrophysiology, German Heart Center Munich, Technische Universitaet Munich, Germany.
authors.forename: Marc
authors.initials: M
authors.lastname: Kottmaier
authors.affiliation: Department of Electrophysiology, German Heart Center Munich, Technische Universitaet Munich, Germany.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Buiatti
authors.affiliation: Department of Electrophysiology, German Heart Center Munich, Technische Universitaet Munich, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Grebmer
authors.affiliation: Department of Electrophysiology, German Heart Center Munich, Technische Universitaet Munich, Germany.
authors.forename: Marta
authors.initials: M
authors.lastname: Telishevska
authors.affiliation: Department of Electrophysiology, German Heart Center Munich, Technische Universitaet Munich, Germany.
authors.forename: Verena
authors.initials: V
authors.lastname: Semmler
authors.affiliation: Department of Electrophysiology, German Heart Center Munich, Technische Universitaet Munich, Germany.
authors.forename: Carsten
authors.initials: C
authors.lastname: Lennerz
authors.affiliation: Department of Electrophysiology, German Heart Center Munich, Technische Universitaet Munich, Germany.
authors.forename: Christine
authors.initials: C
authors.lastname: Schneider
authors.affiliation: Department of Electrophysiology, German Heart Center Munich, Technische Universitaet Munich, Germany.
authors.forename: Christof
authors.initials: C
authors.lastname: Kolb
authors.affiliation: Department of Electrophysiology, German Heart Center Munich, Technische Universitaet Munich, Germany.
authors.forename: Isabel
authors.initials: I
authors.lastname: Deisenhofer
authors.affiliation: Department of Electrophysiology, German Heart Center Munich, Technische Universitaet Munich, Germany.
authors.forename: Tilko
authors.initials: T
authors.lastname: Reents
mesh_terms: D020811:Biomedical Technology / Q000295:instrumentation / Q000592:standards*; D062906:Cardiac Catheters / Q000592:standards*; D017115:Catheter Ablation / Q000295:instrumentation / Q000592:standards*; D055590:Electromagnetic Phenomena; D004867:Equipment Design / Q000295:instrumentation / Q000592:standards*
keywords: 3D mapping systems; Smarttouch Surround Flow catheter; catheter ablation; contact force