Implanted cardiac defibrillator care in radiation oncology patient population

To review the experience of a large cancer center with radiotherapy (RT) patients bearing implantable cardiac defibrillators (ICDs) to propose some preliminary care guidelines as we learn more about the devices and their interaction with the therapeutic radiation environment.

We collected data on patients with implanted ICDs treated with RT during a 2.5-year period at any of the five Memorial Sloan-Kettering clinical campuses. Information regarding the model, location, and dose detected from the device, as well as the treatment fields, fraction size, and treatment energy was collected. During this time, a new management policy for these patients had been implemented requiring treatment with low-energy beams (6 MV) and close surveillance of the patients in partnership with their electrophysiologist, as they received RT.

During the study period, 33 patients were treated with an ICD in place. One patient experienced a default of the device to its initial factory setting that was detected by the patient hearing an auditory signal from the device. This patient had initially been treated with a 15-MV beam. After this episode, his treatment was replanned to be completed with 6-MV photons, and he experienced no further events.

Patients with ICDs and other implanted computer-controlled devices will be encountered more frequently in the RT department, and proper management is important. We present a policy for the safe treatment of these patients in the radiation oncology environment.