Long-Term Prognosis of Patients with an Implantable Cardioverter-Defibrillator in Korea

Yonsei Med J. 2017 May;58(3):514-520. doi: 10.3349/ymj.2017.58.3.514.

Abstract

Purpose: The objective of this study was to elucidate the long-term prognosis of patients with implantable cardioverter-defibrillators (ICDs) in Korea.

Materials and methods: We enrolled 405 patients (age, 57.7±16.7 years; 311 men) who had undergone ICD implantation. The patients were divided into three groups: heart failure (HF) and ICD for primary (group 1, n=118) and secondary prevention (group 2, n=93) and non-HF (group 3, n=194). We compared appropriate and inappropriate ICD therapy delivery among the groups and between high- (heart rate ≥200 /min) and low-rate (<200 /min) ICD therapy zones.

Results: During the follow-up period (58.9±49.8 months), the annual appropriate ICD therapy rate was higher in group 2 (10.4%) than in groups 1 and 3 (6.1% and 5.9%, respectively, p<0.001). There were no significant differences in annual inappropriate ICD therapy rate among the three groups. In group 1, the annual appropriate ICD therapy rate was significantly lower in patients with a high-rate versus a low-rate therapy zone (4.5% and 9.6%, respectively, p=0.026). In group 3, the annual inappropriate ICD therapy rate was significantly lower in patients with a high-rate versus a low-rate therapy zone (3.1% and 4.0%, respectively, p=0.048).

Conclusion: Appropriate ICD therapy rates are not low in Korean patients with ICD, relative to prior large-scale studies in Western countries. Appropriate and inappropriate ICD therapy could be reduced by a high-rate therapy zone in patients with HF and ICD for primary prevention, as well as non-HF patients, respectively.

Keywords: Heart failure; implantable cardioverter-defibrillator; primary prevention; sudden cardiac death.

MeSH terms

  • Aged
  • Death, Sudden, Cardiac / ethnology*
  • Defibrillators, Implantable*
  • Female
  • Follow-Up Studies
  • Heart Failure / therapy*
  • Humans
  • Inappropriate Prescribing
  • Male
  • Medical Errors / prevention & control*
  • Middle Aged
  • Primary Prevention / methods*
  • Prognosis
  • Republic of Korea
  • Secondary Prevention