title: Does left atrial appendage peak emptying flow velocity predict the electrical energy required to achieve successful direct-current cardioversion in patients with persistent atrial fibrillation?
abstract: BACKGROUND
  The relation of left atrial (LA) appendage peak emptying flow velocity (LAAEV) with energy requirement for successful direct-current cardioversion (DCCV) in persistent atrial fibrillation (AF) is unknown. LAAEV correlates with success of cardioversion of AF to sinus rhythm, both of which are related to the LA size and the chronicity of AF. We tested the hypothesis that LAAEV can predict optimal energy required for DCCV in persistent AF (>48 hours).
  
  
  METHODS
  We studied 1050 consecutive patients with persistent AF who underwent successful transesophageal echocardiographically guided DCCV from 2000 to 2005. After excluding patients with atrial flutter and those receiving antiarrhythmic drugs, 454 patients qualified for the study.
  
  
  RESULTS
  LAAEV did not correlate with cardioversion energy (r = 0.06, P = .23) or number of shocks required for successful DCCV (r = 0.05, P = .33). The only predictor of energy required for successful cardioversion was the chronicity of AF.
  
  
  CONCLUSIONS
  LAAEV does not predict electrical energy required for successful cardioversion in persistent AF.
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota 55905, USA. melduni.rowlens@mayo.edu <melduni.rowlens@mayo.edu>
authors.forename: Rowlens M
authors.initials: RM
authors.lastname: Melduni
authors.forename: Krishnaswamy
authors.initials: K
authors.lastname: Chandrasekaran
authors.forename: Paul A
authors.initials: PA
authors.lastname: Friedman
authors.forename: Roger D
authors.initials: RD
authors.lastname: White
authors.forename: Joseph F
authors.initials: JF
authors.lastname: Malouf
authors.forename: David O
authors.initials: DO
authors.lastname: Hodge
authors.forename: James B
authors.initials: JB
authors.lastname: Seward
authors.forename: Jae K
authors.initials: JK
authors.lastname: Oh
authors.forename: Naser M
authors.initials: NM
authors.lastname: Ammash
mesh_terms: D000368:Aged; D020517:Atrial Appendage / Q000000981:diagnostic imaging*; D001281:Atrial Fibrillation / Q000000981:diagnostic imaging* / Q000628:therapy*; D001783:Blood Flow Velocity; D004554:Electric Countershock / Q000379:methods*; D004735:Energy Transfer; D005260:Female; D006325:Heart Atria / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D011379:Prognosis; D013813:Therapy, Computer-Assisted / Q000379:methods*; D016896:Treatment Outcome; D014463:Ultrasonography