Management of patients with implantable cardioverter-defibrillators and pacemakers who require radiation therapy

Background Radiation therapy (RT) may pose acute and long-term risks for patients with cardiac implantable electronic devices (CIEDs), including pacemakers (PMs) and implantable cardioverter-defibrillators (ICDs). However, the frequency of these problems has not been accurately defined. Objective The purpose of this study was to determine the prevalence of CIEDs among patients requiring RT and report the common CIED-related problems when patients are managed according to a standard clinical care path. Methods In a single tertiary-care center, we prospectively screened all patients requiring RT and identified patients with ICDs or PMs. We collected clinical data about their cancer, RT treatment plan, and CIED. Radiation dose to the device was estimated in all patients, and any device malfunction during RT was documented. Results Of the 34,706 consecutive patients receiving RT, 261 patients (0.8%, mean age 77.9 ± 9.4 years) had an implantable cardiac device: 54 (20.7%) ICDs and 207 (79.3%) PMs. The site of RT was head and neck (27.4%), chest (30.0%), and abdomen/pelvis (32.6%). Using our care path, 63.2% of patients required continuous cardiac monitoring, 14.6% required device reprogramming, 18.8% required magnet application during RT, and 3.4% required device repositioning to the contralateral side before RT. Four patients (1.5%) had inappropriate device function during RT: 3 experienced hemodynamically tolerated ventricular pacing at the maximum sensor rate, and 1 experienced a device power-on-reset. No patient died or suffered permanent device failure. Conclusion Nearly 1% of patients receiving RT in this series has a PM or ICD. However, with a systematic policy of risk assessment and patient management, significant device-related complications are rare.