title: Effects of flecainide on exercise-induced ventricular arrhythmias and recurrences in genotype-negative patients with catecholaminergic polymorphic ventricular tachycardia.
abstract: BACKGROUND
  Conventional therapy with beta-blockers is incompletely effective in preventing arrhythmic events in patients with catecholaminergic polymorphic ventricular tachycardia (CPVT). We have previously discovered that flecainide in addition to conventional drug therapy prevents ventricular arrhythmias in patients with genotype-positive CPVT.
  
  
  OBJECTIVE
  To study the efficacy of flecainide in patients with genotype-negative CPVT.
  
  
  METHODS
  We studied the efficacy of flecainide for reducing ventricular arrhythmias during exercise testing and preventing arrhythmia events during long-term follow-up.
  
  
  RESULTS
  Twelve patients with genotype-negative CPVT were treated with flecainide. Conventional therapy failed to control ventricular arrhythmias in all patients. Flecainide was initiated because of significant ventricular arrhythmias (n = 8), syncope (n = 3), or cardiac arrest (n = 1). At the baseline exercise test before flecainide, 6 patients had ventricular tachycardia and 5 patients had bigeminal or frequent ventricular premature beats. Flecainide reduced ventricular arrhythmias at the exercise test in 8 patients compared to conventional therapy, similar to that in patients with genotype-positive CPVT in our previous report. Notably, flecainide completely prevented ventricular arrhythmias in 7 patients. Flecainide was continued in all patients except for one who had ventricular tachycardia at the exercise test on flecainide. During a follow-up of 48±94 months, arrhythmia events (sudden cardiac death and aborted cardiac arrest) associated with noncompliance occurred in 2 patients. Flecainide was not discontinued owing to side effects in any of the patients.
  
  
  CONCLUSIONS
  Flecainide was effective in patients with genotype-negative CPVT, suggesting that spontaneous Ca(2+) release from ryanodine channels plays a role in arrhythmia susceptibility, similar to that in patients with genotype-positive CPVT.
authors.affiliation: Division of Cardiology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Watanabe
authors.forename: Christian
authors.initials: C
authors.lastname: van der Werf
authors.forename: Ferran
authors.initials: F
authors.lastname: Roses-Noguer
authors.forename: Arnon
authors.initials: A
authors.lastname: Adler
authors.forename: Naokata
authors.initials: N
authors.lastname: Sumitomo
authors.forename: Christian
authors.initials: C
authors.lastname: Veltmann
authors.forename: Raphael
authors.initials: R
authors.lastname: Rosso
authors.forename: Zahurul A
authors.initials: ZA
authors.lastname: Bhuiyan
authors.forename: Hennie
authors.initials: H
authors.lastname: Bikker
authors.forename: Prince J
authors.initials: PJ
authors.lastname: Kannankeril
authors.forename: Minoru
authors.initials: M
authors.lastname: Horie
authors.forename: Tohru
authors.initials: T
authors.lastname: Minamino
authors.forename: Sami
authors.initials: S
authors.lastname: Viskin
authors.forename: Björn C
authors.initials: BC
authors.lastname: Knollmann
authors.forename: Jan
authors.initials: J
authors.lastname: Till
authors.forename: Arthur A M
authors.initials: AA
authors.lastname: Wilde
mesh_terms: D000293:Adolescent; D000319:Adrenergic beta-Antagonists / Q000009:adverse effects / Q000627:therapeutic use; D000328:Adult; D000889:Anti-Arrhythmia Agents / Q000009:adverse effects / Q000627:therapeutic use*; D002648:Child; D015331:Cohort Studies; D004562:Electrocardiography; D005080:Exercise Test / Q000009:adverse effects*; D005260:Female; D005424:Flecainide / Q000009:adverse effects / Q000627:therapeutic use*; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D011446:Prospective Studies; D018570:Risk Assessment; D016019:Survival Analysis; D017180:Tachycardia, Ventricular / Q000175:diagnosis / Q000188:drug therapy* / Q000209:etiology / Q000235:genetics / Q000401:mortality / Q000503:physiopathology; D016896:Treatment Outcome; D055815:Young Adult; D000098850:Polymorphic Catecholaminergic Ventricular Tachycardia
chemical_list: D000319:Adrenergic beta-Antagonists; D000889:Anti-Arrhythmia Agents; D005424:Flecainide