Cardiac implantable electronic devices and radiation therapy: long-term outcomes

The prevalence of cancer and the number of patients living with cardiac implantable electronic devices (CIEDs) continue to rise. Consequently, an increasing proportion of patients with CIEDs require radiation therapy (RT).1–3 Although RT is generally considered safe, concerns persist regarding device malfunction, particularly with high energies and dose per generator.4,5 Current European Society of Cardiology (ESC) Cardio-Oncology and national recommendations provide structured risk stratification and management pathways, but focus primarily on acute device safety.6 However, real-world data validating these recommendations remain limited, and long-term post-RT device outcomes have not been systematically evaluated.7–9 Given the stochastic nature of radiation effects, delayed CIED dysfunction may be a concern. In 2016, a dedicated cardio-oncology programme was established between a tertiary RT centre and a high-volume cardiac electrophysiology department.10 This analysis reports early- and long-term outcomes of patients managed within this framework. All consecutive patients with any CIED who underwent RT between January 2015 and January 2024 were included. Prior to RT, patients underwent joint evaluation by a radiation oncologist and a cardiologist experienced in CIEDs. RT assessment included beam energy, estimated dose to the device, and distance between the irradiated target and generator, while risk stratification followed ESC recommendations. Photon energies