Electrophysiologic study-guided amiodarone for sustained ventricular tachyarrhythmias associated with structural heart diseases.
BACKGROUND
Although an electrophysiologic study (EPS) and Holter-monitoring are often helpful in evaluating the efficacy of antiarrhythmic drugs in patients with ventricular tachyarrhythmias (ventricular tachycardia/fibrillation (VT/VF)), the efficacy of EPS- or Holter-guided oral amiodarone therapy in Japanese patients is still unclear.


RESULTS
EPS was performed 1 month after starting amiodarone, and Holter-monitoring was recorded before and 1 month after amiodarone in 188 patients with sustained VT/VF because of structural heart diseases. In spite of the judgment of EPS (n=89) or Holter (n=75), all patients continued amiodarone. Patients were followed up to 3 years and the primary endpoint was VT/VF recurrence and secondary endpoint was death by all cause. Kaplan-Meier estimated the risk of VT/VF recurrence was significantly smaller with EPS-guided amiodarone (p<0.01) but not with Holter-guided amiodarone. Multivariate Cox hazard analysis revealed that EPS-guided amiodarone was an independent factor suppressing the recurrence of VT/VF (p<0.05, 95% confidence interval =0.15 to 0.96). In the subgroup analysis, EPS-guided amiodarone was effective in patients with relatively well-preserved left ventricular ejection fraction (LVEF > or =0.30) but not in patients with lower LVEF (LVEF <0.30).


CONCLUSIONS
EPS-guided amiodarone was useful for preventing recurrence of VT/VF in patients with a relatively well-preserved LVEF, but not always beneficial in patients with a lower LVEF.
Aiba
Takeshi
T
Division of Cardiology, Department of Internal Medicine, National Cardiovascular Center, Suita, Japan.
Yamagata
Kenichiro
K
Shimizu
Wataru
W
Taguchi
Atsushi
A
Satomi
Kazuhiro
K
Noda
Takashi
T
Okamura
Hideo
H
Suyama
Kazuhiro
K
Aihara
Naohiko
N
Kamakura
Shiro
S
Kurita
Takashi
T
D000368:Aged; D000638:Amiodarone / Q000008:administration & dosage*; D003643:Death; D015716:Electrocardiography, Ambulatory; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006331:Heart Diseases; D006801:Humans; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D013318:Stroke Volume; D017180:Tachycardia, Ventricular / Q000188:drug therapy*; D016896:Treatment Outcome
D000638:Amiodarone