Radiation therapy-induced electrical reset of an implantable cardioverter defibrillator device located outside the irradiation field.

Given the overlap in risk factors for cardiac and malignant disease, some patients carrying implantable cardioverter defibrillators (ICDs) may require radiotherapy. Although pacemaker malfunction caused by radiotherapy is well known, few data exist on interactions between ICDs and radiation therapy. This report presents a patient with a single-chamber ICD and a history of bronchial carcinoma. During radiotherapy, electrical restart of the ICD device had occurred, although the device was not located inside the irradiation field. This case report highlights the diagnostic challenge represented by the environment of therapeutic radiation.