Effectiveness of Implantable Cardioverter-Defibrillator Therapy for Heart Failure Patients according to Ischemic or Non-Ischemic Etiology in Korea.
OBJECTIVE
This study was performed to describe clinical characteristics of patients with left ventriculars (LV) dysfunction and implantable cardioverter-defibrillator (ICD), and to evaluate the effect of ICD therapy on survival in Yeongnam province of Korea.


METHODS
From a community-based device registry (9 centers, Yeongnam province, from November 1999 to September 2012), 146 patients with LV dysfunction and an ICD implanted for primary or secondary prophylaxis, were analyzed. The patients were divided into two groups, based on the etiology (73 with ischemic cardiomyopathy and 73 with non-ischemic cardiomyopathy), and indication for the device implantation (36 for primary prevention and 110 for secondary prevention). The cumulative first shock rate, all cause death, and type and mode of death, were determined according to the etiology and indication.


RESULTS
Over a mean follow-up of 3.5 years, the overall ICD shock rate was about 39.0%. ICD shock therapy was significantly more frequent in the secondary prevention group (46.4% vs. 16.7%, p=0.002). The cumulative probability of a first appropriate shock was higher in the secondary prevention group (p=0.015). There was no significant difference in the all-cause death, cardiac death, and mode of death between the groups according to the etiology and indication.


CONCLUSIONS
Studies from this multicenter regional registry data shows that in both ischemic and non-ischemic cardiomyopathy patients, the ICD shock therapy rate was higher in the secondary prevention group than primary prevention group.
Division of Cardiology, Department of Internal Medicine, Yeungnam University Medical Center, Daegu, Korea.
Kyu-Hwan
KH
Park
Division of Cardiology, Department of Internal Medicine, Yeungnam University Medical Center, Daegu, Korea.
Chan-Hee
CH
Lee
Division of Cardiology, Department of Internal Medicine, Daegu Fatima Hospital, Daegu, Korea.
Byung Chun
BC
Jung
Division of Cardiology, Department of Internal Medicine, Kyungpook National University Hospital, Daegu, Korea.
Yongkeun
Y
Cho
Division of Cardiology, Department of Internal Medicine, Kyungpook National University Hospital, Daegu, Korea.
Myung Hwan
MH
Bae
Division of Cardiology, Department of Internal Medicine, Keimyung University Dongsan Medical Center, Daegu, Korea.
Yoon-Nyun
YN
Kim
Division of Cardiology, Department of Internal Medicine, Keimyung University Dongsan Medical Center, Daegu, Korea.
Hyoung-Seob
HS
Park
Division of Cardiology, Department of Internal Medicine, Keimyung University Dongsan Medical Center, Daegu, Korea.
Seongwook
S
Han
Division of Cardiology, Department of Internal Medicine, Catholic University Medical Center, Daegu, Korea.
Young Soo
YS
Lee
Cardiovascular Center, Andong Medical Group, Andong, Korea.
Dae-Woo
DW
Hyun
Division of Cardiology, Department of Internal Medicine, Pusan National University Yangsan Hospital, Yangsan, Korea.
Jun
J
Kim
Division of Cardiology, Department of Internal Medicine, Inje University Busan Paik Hospital, Busan, Korea.
Dae Kyeong
DK
Kim
Division of Cardiology, Department of Internal Medicine, Kosin University Gospel Hospital, Busan, Korea.
Tae-Jun
TJ
Cha
Division of Cardiology, Department of Internal Medicine, Yeungnam University Medical Center, Daegu, Korea.
Dong-Gu
DG
Shin
Heart failure; Implantable cardioverter-defibrillator; Left ventricular dysfunction; Mortality