T wave alternans for predicting adverse effects of amiodarone in a patient with dilated cardiomyopathy.
An implantable cardioverter defibrillator (ICD) was used in a 62-year-old man with dilated cardiomyopathy (DCM) because of hemodynamically intolerable ventricular tachycardia (VT). Amiodarone was administered after a second episode of ICD discharge. Three weeks later, incessant VT appeared, and DC discharge failed to terminate it. Microvolt T wave alternans (TWA), measured by a spectral method, was observed in this patient with and without amiodarone administration. The onset heart rate with TWA was lower and the alternans voltage was higher with amiodarone than without it. The effects of amiodarone appeared to be related to the exacerbation of VT and an increased defibrillation threshold. TWA might be useful in predicting the proarrhythmic effects of amiodarone in similar cases.
Matsuyama
T
T
Third Department of Internal Medicine, Showa University School of Medicine, Tokyo, Japan.
Tanno
K
K
Kobayashi
Y
Y
Obara
C
C
Ryu
S
S
Adachi
T
T
Ezumi
H
H
Asano
T
T
Miyata
A
A
Koba
S
S
Baba
T
T
Katagiri
T
T
D000638:Amiodarone / Q000009:adverse effects* / Q000627:therapeutic use; D000889:Anti-Arrhythmia Agents / Q000009:adverse effects* / Q000627:therapeutic use; D002311:Cardiomyopathy, Dilated / Q000188:drug therapy* / Q000503:physiopathology; D017147:Defibrillators, Implantable; D004562:Electrocardiography; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000187:drug effects; D011237:Predictive Value of Tests
D000889:Anti-Arrhythmia Agents; D000638:Amiodarone