title: Clinical Utility of Atrial Electromechanical Conduction Time Measured with Speckle Tracking Echocardiography after Catheter Ablation in Patients with Atrial Fibrillation: A Validation Study with Electroanatomical Mapping.
abstract: OBJECTIVE
  Our recent report demonstrated that atrial electromechanical conduction time (EMT-ε) measured with speckle tracking echocardiography could predict cardiac events in patients with pathological left ventricular hypertrophy. This study aimed to validate EMT-ε by comparison with electroanatomical mapping and to investigate the clinical utility of EMT-ε in patients with atrial fibrillation (AF) undergoing catheter ablation.
  
  
  METHODS
  Forty-six patients with preserved LV ejection fraction (LVEF ≥ 50%) undergoing pulmonary vein isolation (PVI) for AF were studied. Atrial electrical conduction delay was determined by measuring atrial electrical activation time (EAT) using three-dimensional electroanatomical mapping just after PVI. Echocardiographic parameters were acquired within 24 hours and at 6 months after PVI. The study also included 10 control subjects.
  
  
  RESULTS
  AF patients had a larger left atrial (LA) volume index (LAVI) and more prolonged EMT-ε compared with control subjects. According to the validation study, EAT was closely related to EMT-ε and a', and this association was independent of LAVI and the presence of persistent AF (EMT-ε: R(2) = 0.342, P < 0.0001, a': R(2) = 0.337, P < 0.0001). At 6 months after PVI, LAVI and EMT-ε were significantly improved. During continued follow-up beyond 6 months (total follow-up, 26 ± 12 months), the EMT-ε shortening at 6 months after PVI was significantly greater in AF-free patients than patients with AF recurrence.
  
  
  CONCLUSIONS
  This study suggested that the EMT-ε could be a useful echocardiographic marker of LA electromechanical abnormalities in patients with AF.
authors.affiliation: Department of Cardiology, Pulmonology, Hypertension & Nephrology, Ehime University Graduate School of Medicine, Toon, Ehime, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Fujii
authors.affiliation: Department of Cardiology, Pulmonology, Hypertension & Nephrology, Ehime University Graduate School of Medicine, Toon, Ehime, Japan. katsuji@m.ehime-u.ac.jp.
authors.forename: Katsuji
authors.initials: K
authors.lastname: Inoue
authors.affiliation: Department of Cardiology, Pulmonology, Hypertension & Nephrology, Ehime University Graduate School of Medicine, Toon, Ehime, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Nagai
authors.affiliation: Department of Cardiology, Pulmonology, Hypertension & Nephrology, Ehime University Graduate School of Medicine, Toon, Ehime, Japan.
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Nishimura
authors.affiliation: Department of Cardiology, Pulmonology, Hypertension & Nephrology, Ehime University Graduate School of Medicine, Toon, Ehime, Japan.
authors.forename: Teruyoshi
authors.initials: T
authors.lastname: Uetani
authors.affiliation: Department of Cardiology, Pulmonology, Hypertension & Nephrology, Ehime University Graduate School of Medicine, Toon, Ehime, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Suzuki
authors.affiliation: Department of Cardiology, National Hospital Organization Ehime Medical Center, Toon, Ehime, Japan.
authors.forename: Jun-Ichi
authors.initials: J
authors.lastname: Funada
authors.affiliation: Department of Cardiology, Pulmonology, Hypertension & Nephrology, Ehime University Graduate School of Medicine, Toon, Ehime, Japan.
authors.forename: Takafumi
authors.initials: T
authors.lastname: Okura
authors.affiliation: Department of Cardiology, Pulmonology, Hypertension & Nephrology, Ehime University Graduate School of Medicine, Toon, Ehime, Japan.
authors.forename: Jitsuo
authors.initials: J
authors.lastname: Higaki
authors.affiliation: Department of Cardiology, Pulmonology, Hypertension & Nephrology, Ehime University Graduate School of Medicine, Toon, Ehime, Japan.
authors.forename: Akiyoshi
authors.initials: A
authors.lastname: Ogimoto
mesh_terms: D001281:Atrial Fibrillation / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery*; D018780:Body Surface Potential Mapping / Q000379:methods*; D017115:Catheter Ablation; D004452:Echocardiography / Q000379:methods*; D054459:Elasticity Imaging Techniques / Q000379:methods; D056966:Excitation Contraction Coupling; D005260:Female; D006325:Heart Atria / Q000000981:diagnostic imaging / Q000503:physiopathology; D006329:Heart Conduction System / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D009431:Neural Conduction; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome
keywords: atrial fibrillation; myocardial strain