Potential roles of the wearable cardioverter-defibrillator in acute phase care of patients at high risk of sudden cardiac death: A single-center Japanese experience.
The wearable cardioverter-defibrillator (WCD) has been expected to play a role as an effective bridge therapy to implantable cardioverter-defibrillator (ICD) implantation in patients at high risk of ventricular tachyarrhythmias (VA). Although WCD has been available since April 2014 in Japan, its usefulness remains unclear.



During the early period after hospitalization, patients at high risk of VA after excluding some elderly patients were prescribed WCD. The consecutive 50 patients with WCD use (median age 56 years, 38 for secondary prevention) were studied. We analyzed clinical efficacy and safety of WCD, and examined its potential roles. Of the 50 patients, 38 used WCD only during hospitalization. During WCD use [median 16 (IQR 8-33) days], all patients wore WCD for 98% of a day regardless of in or out-of-hospital use. Sustained VA was detected in 4 patients (8%; for primary prevention in 1) with 7 episodes, and 6 of 7 episodes required shock therapy. Of the 6 shock therapies, 4 were for sustained ventricular tachycardia with the median rate of 236beats/min (IQR 203-250), and the other 2 for ventricular fibrillation. Subsequently, only 27 patients (54%) of all underwent ICD implantation following the WCD use, because of reduced risk of VA after optimal pharmacological therapy or improvement in the left ventricular function.



The WCD use for the acute phase care of patients at high risk of VA can be safe and effective, and may be useful for evaluating indication of ICD implantation.
Department of Advanced Management of Cardiac Arrhythmias, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
Shingo
S
Sasaki
Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
Yoshihiro
Y
Shoji
Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
Yuji
Y
Ishida
Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
Takahiko
T
Kinjo
Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
Yuichi
Y
Tsushima
Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
Maiko
M
Seno
Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
Fumie
F
Nishizaki
Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
Taihei
T
Itoh
Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
Kei
K
Izumiyama
Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
Takashi
T
Yokota
Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
Hiroaki
H
Yokoyama
Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
Masahiro
M
Yamada
Department of Advanced Management of Cardiac Arrhythmias, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
Daisuke
D
Horiuchi
Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
Masaomi
M
Kimura
Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
Takumi
T
Higuma
Department of Cardiology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
Hirofumi
H
Tomita
Advanced Arrhythmia Therapeutic Branch, Division of Cardiology, Saiseikai Kumamoto Hospital Cardiovascular Center, Japan. Electronic address: okumura@hirosaki-u.ac.jp.
Ken
K
Okumura
D000328:Adult; D000368:Aged; D016757:Death, Sudden, Cardiac / Q000209:etiology / Q000517:prevention & control*; D047548:Defibrillators / Q000706:statistics & numerical data*; D004554:Electric Countershock / Q000379:methods; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D008875:Middle Aged; D055502:Secondary Prevention / Q000379:methods*; D013610:Tachycardia / Q000209:etiology / Q000517:prevention & control*; D017180:Tachycardia, Ventricular / Q000150:complications / Q000628:therapy; D014693:Ventricular Fibrillation / Q000150:complications / Q000628:therapy; D016277:Ventricular Function, Left
Sudden cardiac death; Ventricular tachyarrhythmias; Wearable cardioverter-defibrillator