title: High correlation of estimated local conduction velocity with natural logarithm of bipolar electrogram amplitude in the reentry circuit of atrial flutter.
abstract: BACKGROUND
  Low conduction velocity (CV) in the area showing low electrogram amplitude (EA) is characteristic of reentry circuit of atypical atrial flutter (AFL). The quantitative relationship between CV and EA remains unclear. We characterized AFL reentry circuit in the right atrium (RA), focusing on the relationship between local CV and bipolar EA on the circuit.
  
  
  RESULTS
  We investigated 26 RA AFL (10 with typical AFL; 10 atypical incisional AFL; 6 atypical nonincisional AFL) using CARTO system. By referring to isochronal and propagation maps delineated during AFL, points activated faster on the circuit were selected (median, 7 per circuit). At the 196 selected points obtained from all patients, local CV measured between the adjacent points and bipolar EA were analyzed. There was a highly significant correlation between local CV and natural logarithm of EA (lnEA) (R(2) = 0.809, P < 0.001). Among 26 AFL, linear regression analysis of mean CV, calculated by dividing circuit length (152.3 ± 41.7 mm) by tachycardia cycle length (TCL) (median 246 msec), and mean lnEA, calculated by dividing area under curve of lnEA during one tachycardia cycle by TCL, showed y = 0.695 + 0.191x (where: y = mean CV, x = lnEA; R(2) = 0.993, P < 0.001). Local CV estimated from EA with the use of this formula showed a highly significant linear correlation with that measured by the map (R(2) = 0.809, P < 0.001).
  
  
  CONCLUSIONS
  The lnEA and estimated local CV show a highly positive linear correlation. CV is possibly estimated by EA measured by CARTO mapping.
authors.affiliation: Department of Advanced Management of Cardiac Arrhythmias.
authors.forename: Taihei
authors.initials: T
authors.lastname: Itoh
authors.affiliation: Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
authors.forename: Masaomi
authors.initials: M
authors.lastname: Kimura
authors.affiliation: Department of Advanced Management of Cardiac Arrhythmias.
authors.forename: Shingo
authors.initials: S
authors.lastname: Sasaki
authors.affiliation: Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
authors.forename: Shingen
authors.initials: S
authors.lastname: Owada
authors.affiliation: Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Horiuchi
authors.affiliation: Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Sasaki
authors.affiliation: Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Ishida
authors.affiliation: Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
authors.forename: Kinjo
authors.initials: K
authors.lastname: Takahiko
authors.affiliation: Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Okumura
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D001282:Atrial Flutter / Q000503:physiopathology* / Q000601:surgery; D016275:Atrial Function / Q000502:physiology; D017115:Catheter Ablation; D022062:Electrophysiologic Techniques, Cardiac / Q000379:methods* / Q000706:statistics & numerical data; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D013611:Tachycardia, Atrioventricular Nodal Reentry / Q000503:physiopathology* / Q000601:surgery; D016896:Treatment Outcome
keywords: atrial flutter; atypical atrial flutter; catheter ablation; conduction; reentry