title: Electrocardiogram changes and atrial arrhythmias in individuals carrying sodium channel SCN5A D1275N mutation.
abstract: The cardiac sodium channel SCN5A regulates atrioventricular and ventricular depolarization as well as cardiac conduction. Patients with cardiac electrical abnormalities have an increased risk of sudden cardiac death (SCD) and cardio-embolic stroke. Optimal management of cardiac disease includes the understanding of association between the causative mutations and the clinical phenotype. A 12-lead electrocardiogram (ECG) is an easy and inexpensive tool for finding risk patients.
  
  
  
  A blood sample for DNA extraction was obtained in a Finnish family with 43 members; systematic 12-lead ECG analysis was performed in 13 of the family members carrying an SCN5A D1275N mutation. Conduction defects and supraventricular arrhythmias, including atrial fibrillation/flutter, atrioventricular nodal re-entry tachycardia (AVNRT) and junctional rhythm were searched for.
  
  
  
  Five (38%) mutation carriers had fascicular or bundle branch block, 10 had atrial arrhythmias; no ventricular arrhythmias were found. Notching of the R- and S waves - including initial QRS fragmentation - and prolonged S-wave upstroke were present in all the affected family members. Notably, four (31%) affected family members had a stroke before the age of 31 and two experienced premature death.
  
  
  
  A 12-lead ECG can be used to predict arrhythmias in SCN5A D1275N mutation carriers. Key messages The 12-lead ECG may reveal cardiac abnormalities even before clinical symptoms occur. Specific ECG findings - initial QRS fragmentation, prolonged S-wave upstroke as well as supraventricular arrhythmias - were frequently encountered in all SCN5A D1257N mutation carriers. ECG follow-up is recommended for all SCN5A D1275N mutation carriers.
authors.affiliation: a Heart Center, Tampere University Hospital , Tampere , Finland.
authors.forename: Sari U M
authors.initials: SUM
authors.lastname: Vanninen
authors.affiliation: a Heart Center, Tampere University Hospital , Tampere , Finland.|b Faculty of Medicine and Life Sciences , University of Tampere , Tampere , Finland.
authors.forename: Kjell
authors.initials: K
authors.lastname: Nikus
authors.affiliation: a Heart Center, Tampere University Hospital , Tampere , Finland.|b Faculty of Medicine and Life Sciences , University of Tampere , Tampere , Finland.|c BioMediTech, University of Tampere , Tampere , Finland.
authors.forename: Katriina
authors.initials: K
authors.lastname: Aalto-Setälä
mesh_terms: D000293:Adolescent; D000328:Adult; D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000235:genetics*; D016275:Atrial Function / Q000235:genetics; D002648:Child; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D005387:Finland; D005838:Genotype; D006325:Heart Atria / Q000000981:diagnostic imaging; D006329:Heart Conduction System / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D062554:NAV1.5 Voltage-Gated Sodium Channel / Q000097:blood*; D010375:Pedigree; D010641:Phenotype; D055815:Young Adult
chemical_list: D062554:NAV1.5 Voltage-Gated Sodium Channel; C568320:SCN5A protein, human
keywords: ECG; SCN5A D1275N mutation; arrhythmias; conduction defects