Survival After Secondary Prevention Implantable Cardioverter-Defibrillator Placement: An Analysis From the NCDR ICD Registry

JACC Clin Electrophysiol. 2017 Jan;3(1):20-28. doi: 10.1016/j.jacep.2016.06.001. Epub 2016 Sep 7.


Objectives: This study sought to define the characteristics and risks of death of patients receiving a physician-designated secondary prevention implantable cardioverter-defibrillator (ICD) in contemporary clinical practice.

Background: Data on utilization and outcomes of ICDs for the secondary prevention of sudden cardiac death (SCD) are limited.

Methods: Patients enrolled in the National Cardiovascular Data Registry's (NCDR) ICD Registry from 2006 to 2009 with a physician-designated secondary prevention indication for ICD implantation were identified and linked to the Social Security Death Master File. Those patients with a history either of tachycardic arrest or sustained ventricular tachycardia (SCD/VT) or of syncope without SCD/VT were included. Kaplan-Meier survival analysis was used to assess mortality. Cox proportional hazards survival modeling was used to assess the risk of death in these groups, adjusting for patient characteristics.

Results: In the study cohort of 46,685 patients (mean age 66 ± 14 years, 73.5% male, 85% white), 78% had SCD/VT and 22% had syncope. Overall mortality was 10.4% at 1 year and 16.4% at 2 years. Compared with patients having SCD/VT, the adjusted hazard of death at 1 year was lower in the patients having syncope (hazard ratio: 0.89; 95% confidence interval: 0.83 to 0.96) but was not significantly different by 2 years (hazard ratio: 0.96; 95% confidence interval: 0.90 to 1.01).

Conclusions: Nearly 9 of 10 patients receiving a secondary prevention ICD in clinical practice are alive 1 year after implantation. The risk of death varies by indication and is highest among patients who survive SCD or sustained VT in the first year after device implantation.

Keywords: arrhythmia; implantable cardioverter-defibrillator; secondary prevention; sudden cardiac death; survival.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Death, Sudden, Cardiac / prevention & control*
  • Defibrillators, Implantable
  • Equipment Design
  • Female
  • Humans
  • Kaplan-Meier Estimate
  • Male
  • Middle Aged
  • Practice Guidelines as Topic
  • Quality of Life
  • Secondary Prevention / methods*
  • Treatment Outcome