title: Accuracy of Voltage Signal Measurement During Radiofrequency Delivery Through the SMARTTOUCH Catheter.
abstract: Current methods for measuring voltage during radiofrequency (RF) ablation (RFA) necessitate turning off the ablation catheter. If voltage could be accurately read without signal attenuation during RFA, turning off the catheter would be unnecessary, allowing continuous ablation. We evaluated the accuracy of the Thermocool SMARTTOUCH catheter for measuring voltage while RF traverses the catheter.
  
  
  
  We studied 26 patients undergoing RFA for arrhythmias. A 7.5F SMARTTOUCH catheter was used for sensing voltage and performing RFA. Data were collected from the Carto-3 3-dimensional mapping system. Voltages were measured during ablation (RF-ON) and immediately before or after ablation (RF-OFF). In evaluating the accuracy of RF-ON measurements, we utilized the RF-OFF measure as the gold standard. We measured 465 voltage signals. The median values were 0.2900 and 0.3100 for RF-ON and RF-OFF, respectively. Wilcoxon signed rank testing showed no significant difference in these values (P = 0.608). The intraclass correlation coefficient (ICC) was 0.96, indicating that voltage measurements were similarly accurate during RF-OFF versus RF-ON. Five patients had baseline atrial fibrillation (AF), for whom 82 ablation points were measured; 383 additional ablation points were measured for the remaining patients. The voltages measured during RF-ON versus RF-OFF were similar in the presence of AF (P = 0.800) versus non-AF rhythm (P = 0.456) (ICC, 0.96 for both).
  
  
  
  Voltage signal measurement was similarly accurate during RF-ON versus RF-OFF independent of baseline rhythm. Physicians should consider not turning off the SMARTTOUCH ablation catheter when measuring voltage during RFA.
authors.affiliation: Department of Cardiology, Texas Heart Institute, University of Texas Health Science Center at Houston, Houston, Texas, USA.
authors.forename: Payam
authors.initials: P
authors.lastname: Safavi-Naeini
authors.affiliation: Department of Medicine, Section of Cardiology, Baylor College of Medicine, University of Texas Health Science Center at Houston, Houston, Texas, USA.
authors.forename: Dreema
authors.initials: D
authors.lastname: Zafar-Awan
authors.affiliation: Department of Biostatistics, School of Public Health, University of Texas Health Science Center at Houston, Houston, Texas, USA.
authors.forename: Hongjian
authors.initials: H
authors.lastname: Zhu
authors.affiliation: Department of Internal Medicine, Jackson Memorial Hospital, University of Miami, Florida, USA.
authors.forename: Gerardo
authors.initials: G
authors.lastname: Zablah
authors.affiliation: Department of Cardiology, Texas Heart Institute, University of Texas Health Science Center at Houston, Houston, Texas, USA.
authors.forename: Anand V
authors.initials: AV
authors.lastname: Ganapathy
authors.affiliation: Department of Medicine, Section of Cardiology, Baylor College of Medicine, University of Texas Health Science Center at Houston, Houston, Texas, USA.
authors.forename: Abdi
authors.initials: A
authors.lastname: Rasekh
authors.affiliation: Department of Medicine, Section of Cardiology, Baylor College of Medicine, University of Texas Health Science Center at Houston, Houston, Texas, USA.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Saeed
authors.affiliation: Department of Medicine, Section of Cardiology, Baylor College of Medicine, University of Texas Health Science Center at Houston, Houston, Texas, USA.
authors.forename: Joanna Esther Molina
authors.initials: JE
authors.lastname: Razavi
authors.affiliation: Department of Cardiology, Texas Heart Institute, University of Texas Health Science Center at Houston, Houston, Texas, USA.|Department of Medicine, Section of Cardiology, Baylor College of Medicine, University of Texas Health Science Center at Houston, Houston, Texas, USA.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Razavi
mesh_terms: D000200:Action Potentials; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D062906:Cardiac Catheters; D017115:Catheter Ablation / Q000009:adverse effects / Q000295:instrumentation*; D017097:Electric Impedance; D022062:Electrophysiologic Techniques, Cardiac / Q000295:instrumentation*; D004867:Equipment Design; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted
keywords: SMARTTOUCH catheter; atrial fibrillation; myocardial voltage; radiofrequency catheter ablation; radiofrequency energy noise; voltage measurement