Turk Kardiyol Dern Ars. 2012; 40(8): 714-718 | DOI: 10.5543/tkda.2012.77642

CyberKnife® can cause inappropriate shock

Nazmiye Çakmak, Hale Yılmaz, Nurten Sayar, Betül Erer
Department of Cardiology, Siyami Ersek Thoracic And Cardiovascular Surgery Training And Research Hospital, Istanbul, Turkey

Implantable cardioverter-defibrillators (ICD) have been increasingly used to treat life-threatening ventricular tachyarrhythmias. Although they have life-saving capabilities, they are very sensitive to electromagnetic energy sources. It has been reported that many problems associated with the mechanism of the detection and termination of tachyarrhythmias of the ICDs occur due to electromagnetic interference (EMI). In spite of the fact that EMI has been decreasingly observed with the latest generation ICDs, problems may still occur during radiotherapy. The CyberKnife is the latest stereotactic radio-surgery technology in the field of radiotherapy, and is currently being used for the treatment of malign neoplasm in the body. It is especially preferred for the treatment of advanced stage and metastatic tumors. Five ICD shocks were detected in a patient during routine ICD controls. When the patient was evaluated, it was determined that he had undergone radiotherapy with CyberKnife® technology because of lung metastasis and rectal adenocarcinoma. It was learnt that he had received the ICD shocks while he had been on radiotherapy. When the stored intracardiac electrograms stored in the memory of the ICD were investigated, it was established that the shocks were inappropriate shocks due to oversensing because of the exposure to EMI.

Keywords: Equipment failure, defibrillators, implantable, radiotherapy dosage/standards; neoplasms/radiotherapy; stereotactic radiosurgery; practice guidelines as topic

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