Purpose

Radiation therapy (RT) in patients with cardiac implantable electronic devices (CIED) carries a risk of device malfunction from radiation exposure. We sought to evaluate the incidence of CIED malfunction in a cohort of patients treated with modern RT techniques.

Methods and Materials

A retrospective analysis of 193 CIED patients treated with RT between 2000 and 2018 was conducted. All patients underwent pre-, intra-, and post-RT CIED interrogations. Patient demographics, CIED details, RT details, including total dose, modality, treatment site, CIED distance from RT field, treatment planning system maximum dose and in vivo dose estimates, and CIED malfunction data were analyzed.

Results

CIEDs in use were mainly pacemakers (single-chamber 10%, dual-chamber 49%) and defibrillators (35%). Patients received a median RT dose of 50 Gy (range, 7-80 Gy), treated with 3-dimensional CRT (47%), intensity modulated RT/volumetric modulated arc therapy (38%), and stereotactic body radiation therapy (10%). Neutron producing energies were used in 13% of the treatments. A strong correlation was noted between treatment planning system estimated maximum dose and in vivo estimated CIED dose when the CIED distance from the treatment field was >3 cm. However, in vivo measurements provide a lower estimated absorbed dose for CIED devices <3 cm from the RT field. During a median follow-up of 24 months (range, 7-64 months), 2 adverse CIED-related events were recorded: a spontaneous defibrillator discharge and a pacemaker malfunction subsequently causing ventricular tachycardia. Both patients received stereotactic body radiation therapy to the thorax, with CIED dose of 5 and 19.2 cGy, respectively. Both events occurred 2 years posttreatment without any intra- or post-RT CIED interrogations changes noted.

Conclusions

In this series of patients treated with modern RT techniques, we observed a CIED malfunction rate of 1.04%. These low event rates establish the safety of delivering modern RT in CIED patients with the possibility of reducing the burden of intra- and posttreatment CIED monitoring.

中文翻译：

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心血管植入式电子设备患者的适形放射治疗：2019 年美国医学物理学家协会第 203 号风险分层审讯计划的实际实施建议

目的

心脏植入式电子设备 (CIED) 患者的放射治疗 (RT) 存在辐射暴露导致设备故障的风险。我们试图评估一组接受现代放疗技术治疗的患者中 CIED 故障的发生率。

方法和材料

对 2000 年至 2018 年间接受放疗的 193 名 CIED 患者进行了回顾性分析。所有患者都接受了放疗前、放疗中和放疗后的 CIED 询问。分析了患者人口统计、CIED 详细信息、RT 详细信息，包括总剂量、方式、治疗部位、CIED 与 RT 野的距离、治疗计划系统最大剂量和体内剂量估计以及 CIED 故障数据。

结果

使用的 CIED 主要是起搏器（单腔 10%，双腔 49%）和除颤器（35%）。患者接受了 50 Gy（范围，7-80 Gy）的中位放疗剂量，接受了 3 维 CRT (47%)、调强放疗/容积调节弧光疗法 (38%) 和立体定向放射疗法 (10%) ）。在 13% 的处理中使用了产生中子的能量。当 CIED 与治疗野的距离大于 3 cm 时，治疗计划系统估计的最大剂量和体内估计的 CIED 剂量之间存在很强的相关性。然而，体内测量为距离 RT 场 <3 cm 的 CIED 设备提供了较低的估计吸收剂量。在 24 个月（范围，7-64 个月）的中位随访期间，记录了 2 起与 CIED 相关的不良事件：自发性除颤器放电和起搏器故障随后导致室性心动过速。两名患者均接受了胸部立体定向放射治疗，CIED 剂量分别为 5 和 19.2 cGy。这两个事件都发生在治疗后 2 年，没有注意到任何放疗内或放疗后 CIED 询问的变化。

结论

在这一系列采用现代放疗技术治疗的患者中，我们观察到 CIED 故障率为 1.04%。这些低事件率确立了在 CIED 患者中实施现代放疗的安全性，并有可能减少治疗中和治疗后 CIED 监测的负担。