Correlation between surface and intracardiac electrocardiogram in a patient with inappropriate defibrillation shocks
Yukio Hosaka1, Masaomi Chinushi, Kenichi Iijima
1The First Department of Internal Medicine, Niigata University School of Medicine.
Abstract:
A 39-year-old man received implantable cardioverter defibrillator (ICD) shocks during sinus rhythm, triggered by an increase in amplitude and oversensing of intracardiac T waves, caused by hyperkalemia. After treatment of hyperkalemia, the T wave morphology normalized, and oversensing and inappropriate ICD shocks were eliminated. Alteration of the intracardiac electrogram was well correlated to the surface electrocardiogram (ECG) changes. Intracardiac T waves can be altered by hyperkalemia and it seems that this alteration can be estimated by surface ECG analysis.
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