Radiotherapy-induced malfunctions of cardiac implantable electronic devices: A meta-analysis

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). Objective: We conducted a systematic review and meta-analysis to examine the association between RT and PM/ICD malfunctions in patients with cancer. Methods: We searched the literature using the PubMed, the Cochrane Library the Web of Science, and Embase for relative publications until April 2022. Of the 550 initially identified studies, 17 retrospective observational studies including 2454 patients were finally analyzed. Results: The meta-analysis showed that RT was associated with an increased risk of ICD malfunctions (odds ratio [OR] 2.75; 95% confidence interval [CI] 1.74–4.33). Five studies were included in the subgroup analysis regarding photon beam energy, showing that radiation-induced CIED failure was more likely to occur in ICDs when beam energy was ≥10 MV (OR 5.28; 95% CI 2.14–13.03). Neutron-generating RT significantly increased the risk of CIED malfunctions (OR 3.97; 95% CI 1.70–9.26), especially the risk of reset (OR 5.79; 95% CI 2.37–14.12; P =.0001). We did not find significant differences in the risk of CIED failure between chest RT and other RT sites (OR 1.09; 95% CI 0.63–1.88). Conclusion: Our meta-analysis suggests that ICDs are more likely to be affected by RT than PMs. These adverse events, especially reset, in patients with cancer were associated with neutron-generating RT and beam energy ≥10 MV. Given the increasing requirement for RT in several patients with cancer as well as the increasing implantation rates of CIEDs, a better risk stratification is needed in this setting.