title: Catecholaminergic polymorphic ventricular tachycardia in children: analysis of therapeutic strategies and outcomes from an international multicenter registry.
abstract: BACKGROUND
  Catecholaminergic polymorphic ventricular tachycardia is an uncommon, potentially lethal, ion channelopathy. Standard therapies have high failure rates and little is known about treatment in children. Newer options such as flecainide and left cardiac sympathetic denervation are not well validated. We sought to define treatment outcomes in children with catecholaminergic polymorphic ventricular tachycardia.
  
  
  RESULTS
  This is a Pediatric and Congenital Electrophysiology Society multicenter, retrospective cohort study of catecholaminergic polymorphic ventricular tachycardia patients diagnosed before 19 years of age. The cohort included 226 patients, including 170 probands and 56 relatives. Symptomatic presentation was reported in 176 (78%). Symptom onset occurred at 10.8 (interquartile range, 6.8-13.2) years with a delay to diagnosis of 0.5 (0-2.6) years. Syncope (P<0.001), cardiac arrest (P<0.001), and treatment failure (P=0.008) occurred more often in probands. β-Blockers were prescribed in 205 of 211 patients (97%) on medication, and 25% experienced at least 1 treatment failure event. Implantable cardioverter defibrillators were placed in 121 (54%) and was associated with electrical storm in 22 (18%). Flecainide was used in 24% and left cardiac sympathetic denervation in 8%. Six deaths (3%) occurred during a cumulative follow-up of 788 patient-years.
  
  
  CONCLUSIONS
  This study demonstrates a malignant phenotype and lengthy delay to diagnosis in catecholaminergic polymorphic ventricular tachycardia. Probands were typically severely affected. β-Blockers were almost universally initiated; however, treatment failure, noncompliance and subtherapeutic dosing were often reported. Implantable cardioverter defibrillators were common despite numerous device-related complications. Treatment failure was rare in the quarter of patients on flecainide. Left cardiac sympathetic denervation was not uncommon although the indication was variable.
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Roston
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Vinocur
authors.forename: Kathleen R
authors.initials: KR
authors.lastname: Maginot
authors.forename: Saira
authors.initials: S
authors.lastname: Mohammed
authors.forename: Jack C
authors.initials: JC
authors.lastname: Salerno
authors.forename: Susan P
authors.initials: SP
authors.lastname: Etheridge
authors.forename: Mitchell
authors.initials: M
authors.lastname: Cohen
authors.forename: Robert M
authors.initials: RM
authors.lastname: Hamilton
authors.forename: Andreas
authors.initials: A
authors.lastname: Pflaumer
authors.forename: Ronald J
authors.initials: RJ
authors.lastname: Kanter
authors.forename: James E
authors.initials: JE
authors.lastname: Potts
authors.forename: Martin J
authors.initials: MJ
authors.lastname: LaPage
authors.forename: Kathryn K
authors.initials: KK
authors.lastname: Collins
authors.forename: Roman A
authors.initials: RA
authors.lastname: Gebauer
authors.forename: Joel D
authors.initials: JD
authors.lastname: Temple
authors.forename: Anjan S
authors.initials: AS
authors.lastname: Batra
authors.forename: Christopher
authors.initials: C
authors.lastname: Erickson
authors.forename: Maria
authors.initials: M
authors.lastname: Miszczak-Knecht
authors.forename: Peter
authors.initials: P
authors.lastname: Kubuš
authors.forename: Yaniv
authors.initials: Y
authors.lastname: Bar-Cohen
authors.forename: Michal
authors.initials: M
authors.lastname: Kantoch
authors.forename: Vincent C
authors.initials: VC
authors.lastname: Thomas
authors.forename: Gabriele
authors.initials: G
authors.lastname: Hessling
authors.forename: Chris
authors.initials: C
authors.lastname: Anderson
authors.forename: Ming-Lon
authors.initials: ML
authors.lastname: Young
authors.forename: Michel
authors.initials: M
authors.lastname: Cabrera Ortega
authors.forename: Yung R
authors.initials: YR
authors.lastname: Lau
authors.forename: Christopher L
authors.initials: CL
authors.lastname: Johnsrude
authors.forename: Anne
authors.initials: A
authors.lastname: Fournier
authors.forename: Prince J
authors.initials: PJ
authors.lastname: Kannankeril
authors.forename: Shubhayan
authors.initials: S
authors.lastname: Sanatani
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000889:Anti-Arrhythmia Agents / Q000009:adverse effects / Q000627:therapeutic use*; D002648:Child; D016757:Death, Sudden, Cardiac / Q000209:etiology / Q000517:prevention & control*; D017147:Defibrillators, Implantable; D004554:Electric Countershock / Q000009:adverse effects / Q000295:instrumentation / Q000401:mortality; D005260:Female; D006801:Humans; D008297:Male; D018579:Patient Selection; D010641:Phenotype; D012042:Registries; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D013562:Sympathectomy / Q000009:adverse effects / Q000401:mortality; D017180:Tachycardia, Ventricular / Q000150:complications / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D013997:Time Factors; D016896:Treatment Outcome; D000098850:Polymorphic Catecholaminergic Ventricular Tachycardia
chemical_list: D000889:Anti-Arrhythmia Agents
keywords: flecainide; implanted cardioverter defibrillator; polymorphic catecholaminergic ventricular tachycardia; sudden unexpected death