Moricizine induced increase in pacing threshold.
A 72-year-old woman who was experiencing incessant ventricular tachycardia and recurrent automatic implantable cardioverter defibrillator (AICD) firing despite amiodarone therapy was referred to the Cleveland Clinic Foundation. Myocardial ischemia and infarction were ruled out by standard means. Several antiarrhythmic medications were tried previously without success. Moricizine, 200 mg three times daily, was initiated and controlled the ventricular tachycardia. However, after the dose of moricizine was titrated upward, the patient became symptomatically bradycardic and the ECG exhibited 2:1 block of her paced rhythm and an increased ventricular pacing threshold.
Girod
John P
JP
Department of Cardiovascular Medicine, Cleveland Clinic Foundation, 9500 Euclid Ave., Desk F-15, Cleveland, OH 44195, USA.
Marrouche
Nassir
N
Chen
Michael S
MS
Natale
Andrea
A
D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use*; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000187:drug effects / Q000503:physiopathology; D006801:Humans; D016293:Moricizine / Q000627:therapeutic use*; D010138:Pacemaker, Artificial; D017180:Tachycardia, Ventricular / Q000503:physiopathology / Q000628:therapy*
D000889:Anti-Arrhythmia Agents; D016293:Moricizine