title: Clinical impact of contact force and its regional variability on efficiency and effectiveness of pulmonary vein isolation for atrial fibrillation.
abstract: The purpose of this study is to analyze the impact of average contact force (CF) and its regional variability during pulmonary vein isolation (PVI) for atrial fibrillation (AF) on periprocedural parameters and midterm outcome.
  
  
  
  This retrospective cohort study enrolled 57 drug-refractory AF patients who underwent initial PVI for AF using an open-irrigated CF catheter (SmartTouch Thermocool, Biosense Webster, Diamond Bar, CA, USA). Thirty patients were assigned to a lower CF (LCF) group (average CF≤10g) and 27 patients to a higher CF (HCF) group (average CF>10g). The relationship between CF and clinical outcome was analyzed.
  
  
  
  Patients were followed-up for 317±57 days after PVI. The CF was 8.1±1.3g in the LCF group and 12.4±1.5g in the HCF group. Higher average CF was associated with shorter ablation time (28±6min vs. 36±9min, p=0.0002) and lower radiofrequency energy delivery (79±18 vs. 99±26, p=0.0016) for PVI. The rate of acute PV reconnection (APVR) was similar in both groups (LCF group 60% vs. HCF group 44%, p=0.36). Four patients (13%) in the LCF group and nine patients (33%) in the HCF group experienced AF-recurrence. Average CF did not impact on AF-recurrence during midterm clinical outcome (p=0.09 by log-rank test). In the non-recurrence group (n=44), average CF was higher at left posterosuperior PV and right anteroinferior PV than that in the recurrence group (n=13) (p=0.012 and p=0.004, respectively).
  
  
  
  Higher average CF decreased ablation time and radiofrequency energy delivery for PVI, but did not decrease APVR rate or improve midterm clinical outcome.
authors.affiliation: Cardiovascular Center, Sakurabashi Watanabe Hospital, Osaka, Japan.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Sotomi
authors.affiliation: Cardiovascular Center, Sakurabashi Watanabe Hospital, Osaka, Japan. Electronic address: koichi@inoue.name.
authors.forename: Koichi
authors.initials: K
authors.lastname: Inoue
authors.affiliation: Department of Medical Engineering, Sakurabashi Watanabe Hospital, Osaka, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Kikkawa
authors.affiliation: Cardiovascular Center, Sakurabashi Watanabe Hospital, Osaka, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Tanaka
authors.affiliation: Cardiovascular Center, Sakurabashi Watanabe Hospital, Osaka, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Toyoshima
authors.affiliation: Cardiovascular Center, Sakurabashi Watanabe Hospital, Osaka, Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Oka
authors.affiliation: Cardiovascular Center, Sakurabashi Watanabe Hospital, Osaka, Japan.
authors.forename: Nobuaki
authors.initials: N
authors.lastname: Tanaka
authors.affiliation: Cardiovascular Center, Sakurabashi Watanabe Hospital, Osaka, Japan.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Orihara
authors.affiliation: Cardiovascular Center, Sakurabashi Watanabe Hospital, Osaka, Japan.
authors.forename: Katsuomi
authors.initials: K
authors.lastname: Iwakura
authors.affiliation: Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine, Osaka, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Sakata
authors.affiliation: Cardiovascular Center, Sakurabashi Watanabe Hospital, Osaka, Japan.
authors.forename: Kenshi
authors.initials: K
authors.lastname: Fujii
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000601:surgery*; D017115:Catheter Ablation / Q000295:instrumentation / Q000379:methods*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000601:surgery*; D012008:Recurrence; D012189:Retrospective Studies; D055815:Young Adult
keywords: Atrial fibrillation; Catheter ablation; Contact force; Pulmonary vein isolation; Reccurence