title: Clinical significance of macroscopic T-wave alternans after sodium channel blocker administration in patients with Brugada syndrome.
abstract: BACKGROUND
  Macroscopic T-wave alternans (TWA) is sometimes observed after sodium channel blocker administration in patients with Brugada syndrome (BS), but little is known about the association between occurrence of TWA and clinical characteristics in BS patients. We investigated the association between spontaneous ventricular fibrillation (VF) occurrence and TWA after pilsicainide, a sodium channel blocker administration in BS patients.
  
  
  RESULTS
  We administered pilsicainide at a dose of 1 mg/kg to 77 BS patients (76 males and one female; mean age, 48.4 years) and examined the association between TWA after pilsicainide administration and clinical characteristics, including age, spontaneous VF, syncope, family history of sudden death, spontaneous coved ST elevation, late potentials (LP), induction of VF by programmed electrical stimulation, and SCN5A mutation. None of the patients had TWA before pilsicainide administration, but TWA became apparent in 17 (22.1%) of the patients after pilsicainide administration. Patients with TWA had a significantly higher incidence of spontaneous VF (52.9% vs 8.3%, P < 0.001) and syncope (58.8% vs 26.7%, P < 0.05) than did patients without TWA. Then, we focused on the association between spontaneous VF and clinical characteristics. Patients with spontaneous VF had a significantly higher incidence of TWA (64.3% vs 12.7%, P < 0.001) and LP positive (92.9% vs 56.5%, P < 0.01) than did patients without spontaneous VF. In multivariate analysis, TWA (P = 0.001) and LP (P = 0.047) appeared as the independent predictor for spontaneous VF.
  
  
  CONCLUSIONS
  TWA after pilsicainide administration is associated with a high risk of clinical VF in patients with BS.
authors.affiliation: Department of Cardiology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan. gmd17011@cc.okayama-u.ac.jp
authors.forename: Takeshi
authors.initials: T
authors.lastname: Tada
authors.forename: Kengo Fukushima
authors.initials: KF
authors.lastname: Kusano
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nagase
authors.forename: Kimikazu
authors.initials: K
authors.lastname: Banba
authors.forename: Daiji
authors.initials: D
authors.lastname: Miura
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Nishii
authors.forename: Atsuyuki
authors.initials: A
authors.lastname: Watanabe
authors.forename: Kazufumi
authors.initials: K
authors.lastname: Nakamura
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Morita
authors.forename: Tohru
authors.initials: T
authors.lastname: Ohe
mesh_terms: D053840:Brugada Syndrome / Q000150:complications / Q000188:drug therapy*; D004562:Electrocardiography / Q000187:drug effects*; D005260:Female; D006801:Humans; D008012:Lidocaine / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*; D008297:Male; D008875:Middle Aged; D026941:Sodium Channel Blockers / Q000008:administration & dosage / Q000009:adverse effects; D014693:Ventricular Fibrillation / Q000139:chemically induced* / Q000175:diagnosis*
chemical_list: D026941:Sodium Channel Blockers; D008012:Lidocaine; C042288:pilsicainide