IMPORTANCE: Little is known about patients who undergo cardiovascular implantable electronic device deactivation. OBJECTIVE: To describe features and outcomes of patients who underwent cardiovascular implantable electronic device deactivation. DESIGN, SETTING, AND PARTICIPANTS: Retrospective review of medical records of 150 patients at a tertiary academic medical center (Mayo Clinic, Rochester, Minnesota). EXPOSURE Cardiovascular implantable electronic device deactivation. MAIN OUTCOMES AND MEASURES: Demographic and clinical data and information regarding advance directives, ethics consultations, palliative medicine consultations, and cardiovascular implantable electronic device deactivations. RESULTS: Of the 150 patients (median age, 79 years; 67% were male), 149 (99%) had poor or terminal prognoses. Overall, 118 patients (79%) underwent deactivation of tachycardia therapies only, and 32 (21%) underwent deactivation of bradycardia therapies with or without tachycardia therapies (6 patients [4%] were pacemaker-dependent). Half of the deactivation requests (51%) were made by surrogates. A majority of deactivations (55%) were carried out by nurses. Although 85 patients (57%) had advance directives, only 1 mentioned the device in the directive. Ethics consultations occurred in 3 patients (2%) and palliative medicine consultations in 64 (43%). The proportions of patients who died within 1 month of device deactivation were similar for those who underwent deactivation of tachycardia therapies only and those who underwent deactivation of bradycardia therapies with or without tachycardia therapies (85% vs 94%; P = .37). CONCLUSIONS AND RELEVANCE: Most requests for cardiovascular implantable electronic device deactivation were for implantable cardioverter-defibrillator-delivered tachycardia therapies only. Many of these requests were made by surrogates. Advance directives executed by patients with these devices rarely addressed device management. Regardless of device therapy, most patients died shortly after device deactivation. Hence, a device deactivation decision may reflect the seriousness of a given patient's underlying illness. Patients with devices should engage in advance care planning to ensure that future care is consistent with their preferences.