Cardiac Implantable Electronic Device Dysfunctions in Patients Undergoing Radiotherapy A Prospective Cohort Study

Impact of Radiotherapy on Malfunctions and Battery Life of Cardiac Implantable Electronic Devices in Cancer Patients

PURPOSE

This study analyses a large number of cancer patients with CIEDs for device malfunction and premature battery depletion by device interrogation after each radiotherapy fraction and compares different guidelines in regard to patient safety.

METHODS

From 2007 to 2022, a cohort of 255 patients was analyzed for CIED malfunctions via immediate device interrogation after every RT fraction.

RESULTS

Out of 324 series of radiotherapy treatments, with a total number of 5742 CIED interrogations, nine device malfunctions (2.8%) occurred. Switching into back-up/safety mode and software errors occurred four times each. Once, automatic read-out could not be performed. The median prescribed cumulative dose at planning target volume (PTV) associated with CIED malfunction was 45.0 Gy (IQR 36.0-64.0 Gy), with a median dose per fraction of 2.31 Gy (IQR 2.0-3.0 Gy). The median maximum dose at the CIED at time of malfunction was 0.3 Gy (IQR 0.0-1.3 Gy). No correlation between CIED malfunction and maximum photon energy (p = 0.07), maximum dose at the CIED (p = 0.59) nor treatment localization (p = 0.41) could be detected. After excluding the nine malfunctions, premature battery depletion was only observed three times (1.2%). Depending on the national guidelines, 1-9 CIED malfunctions in this study would have been detected on the day of occurrence and in none of the cases would patient safety have been compromised.

CONCLUSION

Radiation-induced malfunctions of CIEDs and premature battery depletion are rare. If recommendations of national safety guidelines are followed, only a portion of the malfunctions would be detected directly after occurrence. Nevertheless, patient safety would not be compromised.

Radiation therapy in the thoracic region: Radio-induced cardiovascular disease, cardiac delineation and sparing, cardiac dose constraints, and cardiac implantable electronic devices

Radiation therapy in the thoracic region may deliver incidental ionizing radiation to the surrounding healthy structures, including the heart. Radio-induced heart toxicity has long been a concern in breast cancer and Hodgkin's lymphoma and was deemed a long-term event. However, recent data highlight the need to limit the dose to the heart in less favorable thoracic cancers too, such as lung and esophageal cancers in which incidental irradiation led to increased mortality. This article will summarize available cardiac dose constraints in various clinical settings and the types of radio-induced cardiovascular diseases encountered as well as delineation of cardiac subheadings and management of cardiac devices. Although still not completely deciphered, heart dose constraints remain intensively investigated and the mean dose to the heart is no longer the only dosimetric parameter to consider since the left anterior descending artery as well as the left ventricle should also be part of dosimetry constraints.

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.