Prognostic comparison between implantable cardioverter-defibrillator and amiodarone in cancer patients

Implantable cardioverter-defibrillator (ICD) has been demonstrated to improve survival outcomes compared to amiodarone. However, this effectiveness in cancer patients remains unclear. Given the complexity of cardiovascular management in this population, including cancer stage considerations, we evaluated the relative effectiveness of ICD versus amiodarone in cancer patients.

We linked cancer registry data with administrative records to identify patients newly prescribed amiodarone or who underwent ICD implantation between 2010 and 2015 at 36 hospitals in Osaka Prefecture, Japan. Among 161,125 cancer patients, 339 met the inclusion criteria (amiodarone: n = 281; ICD: n = 58), with a median follow-up of 762 days. Kaplan-Meier analysis revealed that the ICD group had a significantly reduced risk of all-cause mortality compared to the Amiodarone group (Log-rank test, p < .003). Multivariable Cox proportional hazard regression model showed that ICD was an independent prognostic factor (Hazard ratio: 0.47, 95% confidence interval: 0.29-0.79, p = .004). These results were confirmed in a propensity-matched analysis. Among patients with cancer stage: in situ or localized, no significant difference in survival risk was observed between the ICD and Amiodarone groups, and ICD was not significantly associated with all-cause death. Conversely, among patients with cancer stage: regional or distant, the ICD group had a significantly reduced risk of all-cause death compared to the Amiodarone group, and ICD was an independent prognostic factor.

In cancer patients, ICD may improve long-term prognosis compared to amiodarone, especially in patients with advanced cancer stages.