Abstract 15400: Comparison of Clinical Outcomes Between Patients Treated With Single or Dual Chamber Implantable Cardioverter-defibrillator for Secondary Prevention of Sudden Cardiac Death - A Nationwide Cohort Study Using Claims Database
Background: Implantable cardioverter-defibrillators (ICDs) have been considered standard therapy for secondary prevention of sudden cardiac death (SCD). Theoretically, dual-chamber ICDs (Dc-ICDs) have better accuracy in rhythm detection than single-chamber ICDs (Sc-ICDs). In clinical practice, more patients receive Dc-ICDs even though the difference of long-term outcomes between Dc-ICDs and Sc-ICDs remains uncertain.The aim of this study was to compare long-term outcomes between patients receiving Dc-ICDs and Sc-ICDs for secondary prevention of SCD in Taiwan.
Methods: The Taiwan National Health Insurance claims data from 2002 through 2010 was used. Patients aged over 18 years were included if they received an ICD for secondary prevention of SCD. Patients’ records were linked to the National Death Registry to identify mortality outcomes. All patients were followed until occurrence of cardiovascular outcomes, death, heart transplantation, or the end of the study at 31 December 2010, whichever came first. The propensity score was constructed using logistic regression to model receipt of Dc-ICDs or Sc-ICDs as a function of the baseline patient characteristics. Inverse probability-of-treatment weighted method was used to create comparable pseudo-cohorts for analysis. Cox proportional hazards model was used to compare the relative risk of occurrence of specific clinical outcomes between groups.
Results: Of the 1191 enrolled patients, 675 (57%) received Dc-ICDs and 516 (43%) received Sc-ICDs. There was no significant difference in the risk of all-cause mortality between the two groups (adjusted hazard ratio [HR]: 0.83, 95% confidence interval [CI]: 0.68-1.03, p = 0.09). However, Dc-ICD group patients had lower risks of first hospitalization due to ventricular arrhythmia (adjusted HR: 0.46, 95% CI: 0.23-0.92, p = 0.028) and first hospitalization due to syncope (adjusted HR: 0.26, 95% CI: 0.12-0.54, p < 0.001).
Conclusion: Among patients receiving an ICD for secondary prevention of SCD, those who received Dc-ICDs had lower risks of hospitalization due to ventricular arrhythmia and hospitalization due to syncope than those who received Sc-ICDs. There was no difference in long-term survival between two groups.
- © 2013 by American Heart Association, Inc.