title: Evaluation of electrocardiographic parameters in patients with hearing loss genotyped for the connexin 26 gene (GJB2) mutations.
abstract: BACKGROUND
  Several studies have associated congenital sensorineural hearing loss in children with prolongation of the cardiac parameter QTc. The cause of this association is unknown. At the same time, mutations in GJB2, which encodes connexin 26, are the most common cause of congenital hearing impairment.
  
  
  OBJECTIVE
  To compare electrocardiographic parameters (PR interval, QRS complex, and QTc interval) in patients with hearing loss who were tested for mutations in GJB2 and GJB6 to investigate whether these mutations affect electrical activity of the heart.
  
  
  METHODS
  346 patients (176 males, 170 females) with sensorineural hearing loss of 30dB HL or more, aged 21.8±19.9 years (including 147 children <14 years), underwent both genetic study for GJB2 and GJB6 mutations and electrocardiography.
  
  
  RESULTS
  Mutations in GJB2, including homozygotes and heterozygotes, were found in 112 (32%) patients. There were no significant differences in ECG parameters between groups of patients with and without mutations in GJB2. No differences were observed either in men (mean PR with mutation: 155±16.6 vs. 153.6±30.1 without; QRS: 99.9±9.9 vs. 101.1±15.4; QTc: 414.9±29.9 vs. 412.4±25.7) or women (mean PR with: 148.7±21 vs. 143.8±22.8 without; QRS: 94.8±7.6 vs. 92.9±9.6; QTc: 416.8±20.6 vs. 424.9±22.8). In similar fashion, we did we find any significant differences between groups of children with and without GJB2 mutations (mean PR with: 126.3±19.6 vs. 127±19.7 without; QRS: 80.7±9.5 vs. 79.4±11.6; QTc: 419.7±23.5 vs. 419.8±24.8).
  
  
  CONCLUSIONS
  No association was found between the presence of GJB2 mutations encoding connexin 26 in patients with hearing loss and their ECG parameters (PR, QRS, QTc).
authors.affiliation: Institute of Cardiology, Warsaw, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Sanecka
authors.affiliation: Institute of Cardiology, Warsaw, Poland.
authors.forename: Elzbieta Katarzyna
authors.initials: EK
authors.lastname: Biernacka
authors.affiliation: Institute of Physiology and Pathology of Hearing, World Hearing Center, Nadarzyn, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Sosna
authors.affiliation: Institute of Physiology and Pathology of Hearing, World Hearing Center, Nadarzyn, Poland.
authors.forename: Malgorzata
authors.initials: M
authors.lastname: Mueller-Malesinska
authors.affiliation: Medical University of Warsaw, Department of Medical Genetics, Warsaw, Poland.
authors.forename: Rafal
authors.initials: R
authors.lastname: Ploski
authors.affiliation: Institute of Physiology and Pathology of Hearing, World Hearing Center, Nadarzyn, Poland. Electronic address: skarzynski.henryk@ifps.org.pl.
authors.forename: Henryk
authors.initials: H
authors.lastname: Skarzynski
authors.affiliation: Institute of Cardiology, Warsaw, Poland.
authors.forename: Ryszard
authors.initials: R
authors.lastname: Piotrowicz
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D000072259:Connexin 26 / Q000235:genetics*; D004562:Electrocardiography; D005260:Female; D005838:Genotype; D006319:Hearing Loss, Sensorineural / Q000150:complications / Q000235:genetics*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008133:Long QT Syndrome / Q000150:complications / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D055815:Young Adult
chemical_list: D000072259:Connexin 26
keywords: Conexina 26; Connexin 26; ECG; GJB2 mutation; Hearing loss; Mutação de GJB2; Perda auditiva