Nifekalant and disopyramide in a patient with short QT syndrome: evaluation of pharmacological effects and electrophysiological properties.
We assessed several pharmacological effects on electrocardiogram parameters and effective refractory period (ERP) in a patient with a short QT syndrome (SQTS). Pharmacological challenge tests revealed that disopyramide and selective I(kr) blocker, nifekalant normalized QT interval, and ERP of the atrial and ventricular myocardium. This study suggested that disopyramide and nifekalant should be feasible for the drug treatment of the SQTS. Moreover, QT interval was paradoxically prolonged at higher heart rates induced with isoproterenol infusion or an exercise test, although the mechanism of this QT prolongation remains to be investigated.
Cardiovascular Center, Kyoto-Katsura Hospital, Kyoto, Japan. kcvc.mizobuchi@katsura.com
Masahiro
M
Mizobuchi
Yoshihisa
Y
Enjoji
Ryuji
R
Yamamoto
Tsuyoshi
T
Ono
Atsushi
A
Funatsu
Daisuke
D
Kambayashi
Tomoko
T
Kobayashi
Shigeru
S
Nakamura
D000889:Anti-Arrhythmia Agents; D001281:Atrial Fibrillation / Q000175:diagnosis*; D018780:Body Surface Potential Mapping / Q000379:methods*; D004206:Disopyramide / Q000008:administration & dosage*; D006801:Humans; D008297:Male; D011744:Pyrimidinones / Q000008:administration & dosage*; D013577:Syndrome; D017180:Tachycardia, Ventricular / Q000175:diagnosis*; D016896:Treatment Outcome; D055815:Young Adult
D000889:Anti-Arrhythmia Agents; D011744:Pyrimidinones; C076259:nifekalant; D004206:Disopyramide