title: Cardioversion Efficacy Using Pulsed Biphasic or Biphasic Truncated Exponential Waveforms: A Randomized Clinical Trial.
abstract: BACKGROUND
  Several different defibrillators are currently used for cardioversion and defibrillation of cardiac arrhythmias. The efficacy of a novel pulsed biphasic (PB) waveform has not been compared to other biphasic waveforms. Accordingly, this study aims to compare the efficacy and safety of PB shocks with biphasic truncated exponential (BTE) shocks in patients undergoing cardioversion of atrial fibrillation or -flutter.
  
  
  RESULTS
  This prospective, randomized study included patients admitted for elective direct current cardioversion. Patients were randomized to receive cardioversion using either PB or BTE shocks. We used escalating shocks until sinus rhythm was obtained or to a maximum of 4 shocks. Patients randomized to PB shocks received 90, 120, 150, and 200 J and patients randomized to BTE shocks received 100, 150, 200, and 250 J, as recommended by the manufacturers. In total, 69 patients (51%) received PB shocks and 65 patients (49%) BTE shocks. Successful cardioversion, defined as sinus rhythm 4 hours after cardioversion, was achieved in 43 patients (62%) using PB shocks and in 56 patients (86%) using BTE shocks; ratio 1.4 (95% CI 1.1-1.7) (P=0.002). There was no difference in safety (ie, myocardial injury judged by changes in high-sensitive troponin I levels; ratio 1.1) (95% CI 1.0-1.3),P=0.15. The study was terminated prematurely because of an adverse event.
  
  
  CONCLUSIONS
  Cardioversion using a BTE waveform was more effective when compared with a PB waveform. There was no difference in safety between the 2 waveforms, as judged by changes in troponin I levels.
  
  
  BACKGROUND
  URL: http://www.clinicaltrials.gov. Unique identifier: NCT02317029.
authors.affiliation: Clinical Research Unit, Regional Hospital of Randers, Randers NE, Denmark.|Department of Internal Medicine, Regional Hospital of Randers, Randers NE, Denmark.|Research Center for Emergency Medicine, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Anders S
authors.initials: AS
authors.lastname: Schmidt
authors.affiliation: Clinical Research Unit, Regional Hospital of Randers, Randers NE, Denmark.|Department of Internal Medicine, Regional Hospital of Randers, Randers NE, Denmark.|Research Center for Emergency Medicine, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Kasper G
authors.initials: KG
authors.lastname: Lauridsen
authors.affiliation: Department of Internal Medicine, Regional Hospital of Randers, Randers NE, Denmark.|Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark.|Department of Cardiology, Aarhus University Hospital, Aarhus, Denmark.
authors.forename: Kasper
authors.initials: K
authors.lastname: Adelborg
authors.affiliation: Department of Internal Medicine, Regional Hospital of Randers, Randers NE, Denmark.
authors.forename: Peter
authors.initials: P
authors.lastname: Torp
authors.affiliation: Department of Anesthesiology, Regional Hospital of Randers, Randers NE, Denmark.
authors.forename: Leif F
authors.initials: LF
authors.lastname: Bach
authors.affiliation: Department of Anesthesiology, Regional Hospital of Randers, Randers NE, Denmark.
authors.forename: Simon M
authors.initials: SM
authors.lastname: Jepsen
authors.affiliation: Department of Clinical Biochemistry, Regional Hospital of Randers, Randers NE, Denmark.
authors.forename: Nete
authors.initials: N
authors.lastname: Hornung
authors.affiliation: NIHR Southampton Respiratory Biomedical Research Unit, University Hospital Southampton NHS Foundation Trust, Southampton, United Kingdom.
authors.forename: Charles D
authors.initials: CD
authors.lastname: Deakin
authors.affiliation: Department of Internal Medicine, Regional Hospital of Randers, Randers NE, Denmark.
authors.forename: Hans
authors.initials: H
authors.lastname: Rickers
authors.affiliation: Department of Internal Medicine, Regional Hospital of Randers, Randers NE, Denmark bl@clin.au.dk.|Research Center for Emergency Medicine, Aarhus University Hospital, Aarhus, Denmark.|Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.
authors.forename: Bo
authors.initials: B
authors.lastname: Løfgren
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000628:therapy*; D001282:Atrial Flutter / Q000628:therapy*; D004554:Electric Countershock / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome
keywords: atrial fibrillation; biphasic waveforms; cardioversion