title: Predictors of successful cardioversion with vernakalant in patients with recent-onset atrial fibrillation.
abstract: BACKGROUND
  Vernakalant is a novel atrial-selective antiarrhythmic drug able to convert recent-onset atrial fibrillation (AF) with reportedly low proarrhythmic risk. Successful cardioversion predictors are largely unknown. We sought to evaluate clinical and electrocardiographic predictors of cardioversion of recent-onset AF with vernakalant.
  
  
  METHODS
  Consecutive patients with AF ≤48 hours admitted for cardioversion with vernakalant (n = 113, median age 62 years, 69 male) were included. Sinus rhythm (SR) within 90 minutes after infusion start was considered to be successful cardioversion. Predictive values of demographics, concomitant therapy, comorbidities, and electrocardiographic parameters were assessed. Atrial fibrillatory rate (AFR), exponential decay, and mean fibrillatory wave amplitude were measured from surface ECG using QRST cancellation and time-frequency analysis.
  
  
  RESULTS
  Cardioversion was achieved in 66% of patients. Conversion rate was higher in women than in men (80% vs 58%, P = 0.02) while none of other clinical characteristics, including index AF episode duration, could predict SR restoration. Female gender was predictive of vernakalant's effect in logistic regression analysis (OR = 2.82 95%CI 1.18-6.76, P = 0.020). There was no difference in AFR (350 ± 60 vs 348 ± 62 fibrillations per minute [fpm], P = 0.893), mean fibrillatory wave amplitude (86 ± 33 vs 88 ± 67 μV, P = 0.852), or exponential decay (1.30 ± 0.42 vs 1.35 ± 0.42, P = 0.376) between responders and nonresponders.
  
  
  CONCLUSIONS
  Female gender is associated with a higher rate of SR restoration using intravenous (i.v.) vernakalant for recent-onset AF. ECG-derived indices of AF organization, which previous studies associated with effect of rhythm control interventions, did not predict vernakalant's effect.
authors.affiliation: Department of Emergency Medicine; Skåne University Hospital, Malmö, Sweden.
authors.forename: Natalia
authors.initials: N
authors.lastname: Mochalina
authors.forename: Tord
authors.initials: T
authors.lastname: Juhlin
authors.forename: Bertil
authors.initials: B
authors.lastname: Öhlin
authors.forename: Jonas
authors.initials: J
authors.lastname: Carlson
authors.forename: Fredrik
authors.initials: F
authors.lastname: Holmqvist
authors.forename: Pyotr G
authors.initials: PG
authors.lastname: Platonov
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000840:Anisoles / Q000627:therapeutic use*; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use*; D001145:Arrhythmias, Cardiac / Q000150:complications; D001281:Atrial Fibrillation / Q000150:complications / Q000188:drug therapy*; D053840:Brugada Syndrome; D000075224:Cardiac Conduction System Disease; D004562:Electrocardiography / Q000187:drug effects*; D005260:Female; D006329:Heart Conduction System / Q000002:abnormalities* / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D011759:Pyrrolidines / Q000627:therapeutic use*; D012737:Sex Factors; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000840:Anisoles; D000889:Anti-Arrhythmia Agents; D011759:Pyrrolidines; C524581:vernakalant
keywords: atrial fibrillation; atrial fibrillatory rate; predictors of conversion; recent-onset atrial fibrillation; time frequency analysis; vernakalant