Ventricular tachycardia initiated by high energy cardioversion in a patient with an implantable cardioverter defibrillator.
A transvenous implantable cardioverter defibrillator (ICD) was implanted into a 58 year old woman with idiopathic dilated cardiomyopathy who had drug refractory monomorphic ventricular tachycardia (VT). Antitachycardia pacing failed to terminate the VT; termination was attempted at 24 J, which was above the defibrillation threshold. When cardioversion at 24 J was delivered, VT with a different morphology and slower rate was reproducibly initiated. At 3 J, however, the original VT was successfully terminated without initiation of the slower VT. A new VT may be induced by high energy cardioversion. This may be a manifestation of the proarrhythmic potential of ICDs.
Chinushi
M
M
First Department of Internal Medicine, Niigata University School of Medicine, Japan.
Aizawa
Y
Y
Higuchi
K
K
D002311:Cardiomyopathy, Dilated / Q000503:physiopathology / Q000628:therapy; D017147:Defibrillators, Implantable / Q000009:adverse effects*; D004554:Electric Countershock / Q000009:adverse effects*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008875:Middle Aged; D017180:Tachycardia, Ventricular / Q000209:etiology* / Q000503:physiopathology