Nicorandil, a potassium channel opener, abolished torsades de pointes in a patient with complete atrioventricular block.
TdP is a serious complication of AV block. We report a case of complete AV block with QT prolongation who had bouts of TdP resistant to lidocaine and isoproterenol. Temporary pacing could not be performed, because insertion of a pacing lead triggered TdP that deteriorated into ventricular fibrillation. Nicorandil, a potassium channel opener, shortened the QT interval and abolished TdP. This may suggest that potassium channel opening drugs are clinically effective against TdP associated with bradycardia-dependent QT prolongation.
Watanabe
O
O
Third Department of Internal Medicine, Saitama Medical Center, Saitama Medical School, Kawagoe, Japan.
Okumura
T
T
Takeda
H
H
Nakamura
W
W
Segawa
K
K
Ito
H
H
Yoshimoto
N
N
D000368:Aged; D000779:Anesthetics, Local / Q000627:therapeutic use; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use*; D001919:Bradycardia / Q000209:etiology; D002316:Cardiotonic Agents / Q000627:therapeutic use; D004562:Electrocardiography / Q000187:drug effects; D005260:Female; D006327:Heart Block / Q000150:complications*; D006801:Humans; D007545:Isoproterenol / Q000627:therapeutic use; D008012:Lidocaine / Q000627:therapeutic use; D020108:Nicorandil / Q000627:therapeutic use*; D015221:Potassium Channels / Q000187:drug effects*; D016171:Torsades de Pointes / Q000188:drug therapy*; D014693:Ventricular Fibrillation / Q000209:etiology
D000779:Anesthetics, Local; D000889:Anti-Arrhythmia Agents; D002316:Cardiotonic Agents; D015221:Potassium Channels; D020108:Nicorandil; D008012:Lidocaine; D007545:Isoproterenol