title: Flecainide therapy suppresses exercise-induced ventricular arrhythmias in patients with CASQ2-associated catecholaminergic polymorphic ventricular tachycardia.
abstract: BACKGROUND
  Calsequestrin-associated catecholaminergic polymorphic ventricular tachycardia (CPVT2) can cause sudden death in young individuals in response to stress. Beta-blockers are the mainstay medical treatment for patients with CPVT2. However, they do not prevent syncope and sudden death in all patients. Flecainide was reported to reduce exercise-induced ventricular arrhythmias (EIVA) in patients with ryanodine receptor-associated CPVT. The role of flecainide in CPVT2 is not known.
  
  
  OBJECTIVE
  To summarize our experience in combining flecainide and beta-blockers in high-risk patients with CPVT2.
  
  
  METHODS
  All patients with CPVT2 (10 patients) who have high-risk features (syncope, EIVA, or appropriate implantable cardioverter-defibrillator [ICD] shocks) despite beta-blockers with or without calcium channel blockers were treated with a combination of flecainide and beta-blockers. Exercise test was done before and after beginning treatment with flecainide.
  
  
  RESULTS
  All patients had EIVA and 4 had appropriate ICD shocks before flecainide treatment. EIVA-included frequent ventricular premature beats and or ventricular tachycardia during the exercise test while on high dose of beta-blockers with or without calcium channel blockers before treatment with flecainide. After combination therapy with flecainide and beta-blockers, EIVA were suppressed completely in all patients. During follow-up of 15.5 ± 10.4 months (range 2-29 months), 8 patients were free of symptoms and free of arrhythmias. Two patients had 1 VT storm episode with recurrent ICD shocks despite repeated normal stress test.
  
  
  CONCLUSIONS
  Flecainide can completely prevent ventricular arrhythmia during exercise and partially prevent recurrent ICD shocks in high-risk patients with CPVT2.
authors: Department of Pediatric Cardiology.
authors: Asaad
authors: A
authors: Khoury
authors: Ibrahim
authors: I
authors: Marai
authors: Mahmoud
authors: M
authors: Suleiman
authors: Miry
authors: M
authors: Blich
authors: Avraham
authors: A
authors: Lorber
authors: Lior
authors: L
authors: Gepstein
authors: Monther
authors: M
authors: Boulos
mesh_terms: D000293:Adolescent; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D002155:Calsequestrin / Q000235:genetics / Q000378:metabolism*; D004247:DNA / Q000235:genetics; D016757:Death, Sudden, Cardiac / Q000517:prevention & control*; D004562:Electrocardiography; D005080:Exercise Test / Q000009:adverse effects*; D005260:Female; D005424:Flecainide / Q000627:therapeutic use*; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009154:Mutation; D017180:Tachycardia, Ventricular / Q000188:drug therapy / Q000209:etiology* / Q000235:genetics; D016896:Treatment Outcome; D055815:Young Adult; D000098850:Polymorphic Catecholaminergic Ventricular Tachycardia
chemical_list: D000889:Anti-Arrhythmia Agents; C443109:CASQ2 protein, human; D002155:Calsequestrin; D004247:DNA; D005424:Flecainide
keywords: CASQ2; CPVT; CPVT2; Calsequestrin; Catecholaminergic polymorphic ventricular tachycardia; EIVA; Flecainide; ICD; RyR2; VT; calsequestrin; calsequestrin-associated catecholaminergic polymorphic ventricular tachycardia; catecholaminergic polymorphic ventricular tachycardia; exercise-induced ventricular arrhythmias; implantable cardioverter-defibrillator; ryanodine receptor; ventricular tachycardia