Clinical significance of macroscopic T-wave alternans after sodium channel blocker administration in patients with Brugada syndrome.
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.
Tada
Takeshi
T
Department of Cardiology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan. gmd17011@cc.okayama-u.ac.jp
Kusano
Kengo Fukushima
KF
Nagase
Satoshi
S
Banba
Kimikazu
K
Miura
Daiji
D
Nishii
Nobuhiro
N
Watanabe
Atsuyuki
A
Nakamura
Kazufumi
K
Morita
Hiroshi
H
Ohe
Tohru
T
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*
D026941:Sodium Channel Blockers; D008012:Lidocaine; C042288:pilsicainide