CIED malfunction in patients receiving radiation is a rare event that could be detected by remote monitoring

INTRODUCTION: An increasing number of patients with cardiac devices require radiation therapy for treatment of a variety of cancers. This study aimed to identify the incidence and predictors of cardiac implantable electronic devices (CIED) malfunction in a real-world population that has received radiation therapy. METHODS: This retrospective cohort study included 109 adult patients who received radiation therapy at the University of Rochester Medical Center, Radiation Oncology Department, between 2000 and 2015. Sixty patients had pacemakers and 49 had automatic implantable cardioverter defibrillators. Subjects received either high energy (16 MV) and/or low energy (6 MV) photon beams with or without electron beams (6-16 MeV). We included interrogations done from first day of radiation and up to 3 months\u27 postradiation therapy. Outcomes analyzed were device-related malfunctions and device-related clinical events. Fisher\u27s exact, Wilcoxon, and Kruskall-Wallis tests were used for bivariate analysis. Logistic regression with robust adjustment was used for multivariate analysis. RESULTS: We identified six device-related malfunctions. All events were minor and included partial settings reset leading to loss of historical data, pacing thresholds changes, lead impedance changes, and LV output increase. Two patients had device-related clinical events, including dyspnea and diaphragmatic-stimulation. In bivariate analysis, CIED malfunction was associated with CIED duration in situ. In multivariate analysis, there was no significant statistical association between adverse events and beam energy type, CIED location, or dose of radiation delivered to the target. CONCLUSIONS: CIED malfunctions are uncommon in real-world patients and associated with minor clinical events. In our cohort, remote CIED monitoring would have identified all events

Prognostic Model for Intracranial Progression after Stereotactic Radiosurgery: A Multicenter Validation Study

Stereotactic radiosurgery (SRS) is a standard of care for many patients with brain metastases. To optimize post-SRS surveillance, this study aimed to validate a previously published nomogram predicting post-SRS intracranial progression (IP). We identified consecutive patients completing an initial course of SRS across two institutions between July 2017 and December 2020. Patients were classified as low- or high-risk for post-SRS IP per a previously published nomogram. Overall survival (OS) and freedom from IP (FFIP) were assessed via the Kaplan–Meier method. Assessment of parameters impacting FFIP was performed with univariable and multivariable Cox proportional hazard models. Among 890 patients, median follow-up was 9.8 months (95% CI 9.1–11.2 months). In total, 47% had NSCLC primary tumors, and 47% had oligometastatic disease (defined as ≤5 metastastic foci) at the time of SRS. Per the IP nomogram, 53% of patients were deemed high-risk. For low- and high-risk patients, median FFIP was 13.9 months (95% CI 11.1–17.1 months) and 7.6 months (95% CI 6.4–9.3 months), respectively, and FFIP was superior in low-risk patients (p < 0.0001). This large multisite BM cohort supports the use of an IP nomogram as a quick and simple means of stratifying patients into low- and high-risk groups for post-SRS IP