title: Novel Mapping Technique for Localization of Focal and Reentrant Activation During Atrial Fibrillation.
abstract: BACKGROUND
  Identification of wavefront propagation pattern during AF remains challenging in ablation procedures. We sought to test a novel combination of a new mapping technology called Ripple Map and high-density mapping to distinguish focal and reentrant activation during atrial fibrillation (AF).
  
  
  RESULTS
  Subjects were patients undergoing ablation for persistent AF. If AF remained after isolation of the pulmonary veins, the left atrium (LA) was mapped by a high-density mapping catheter for later analysis, after which ablation was continued using a conventional stepwise approach. After the procedure, electrograms from the high-density mapping catheter were analyzed using Ripple Map, which is a new feature in the CARTO®3, and type of activation on ≥3 consecutive AF cycles was determined. High-density mapping was performed on 569 sites in 45 patients (13 ± 3 sites per patient). AF wavefront propagation determined by Ripple Map was in good agreement with analysis of manual annotation of bipolar electrograms. Ripple Map's representation of wavefront activation pattern, which could include local as well as far-field activity, allowed us to identify focal activation in 64 (11%) sites and 1 (0.2%) reentrant activation site. Radiofrequency delivery in atrial regions with activation sites identified as focal by Ripple Map resulted in termination of AF more often than regions without focal activation (22% vs. 7%, P = 0.015).
  
  
  CONCLUSIONS
  This study demonstrated that Ripple Map enabled quick identification of AF wavefront activation pattern, potentially being helpful for determining ablation targets in persistent AF.
authors.affiliation: Department of Cardiology, Disaster Medical Center, Tokyo, Japan.
authors.forename: Yoshihide
authors.initials: Y
authors.lastname: Takahashi
authors.affiliation: Department of Cardiology, Disaster Medical Center, Tokyo, Japan.
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Iwai
authors.affiliation: Department of Cardiology, Disaster Medical Center, Tokyo, Japan.
authors.forename: Syu
authors.initials: S
authors.lastname: Yamashita
authors.affiliation: Department of Cardiology, Disaster Medical Center, Tokyo, Japan.
authors.forename: Mayumi
authors.initials: M
authors.lastname: Masumura
authors.affiliation: Department of Cardiology, Disaster Medical Center, Tokyo, Japan.
authors.forename: Masahito
authors.initials: M
authors.lastname: Suzuki
authors.affiliation: Department of Cardiology, Disaster Medical Center, Tokyo, Japan.
authors.forename: Kento
authors.initials: K
authors.lastname: Yabe
authors.affiliation: Department of Cardiology, Disaster Medical Center, Tokyo, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Sato
authors.affiliation: Heart Rhythm Center, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Kenzo
authors.initials: K
authors.lastname: Hirao
authors.affiliation: Department of Cardiovascular Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Isobe
mesh_terms: D000200:Action Potentials; D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery*; D017115:Catheter Ablation / Q000009:adverse effects; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology / Q000601:surgery*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D016896:Treatment Outcome
keywords: ablation; atrial fibrillation; focal; mapping; persistent; reentry