RATIONALE: Despite increasing number of left ventricular assist device (LVAD) implantation, standardized cardiopulmonary resuscitation (CPR) protocol for patients with LVAD, especially in out-of-hospital settings are not well known. PATIENT CONCERNS: A 41-year-old LVAD implanted man became cardiac arrest in an out-of-hospital setting. Bystander CPR was started and the patient was brought to our hospital without noticing LVAD. Upon arrival, the medical staff noted the LVAD and that the battery of the LVAD was exhausted. DIAGNOSIS: Cardiac arrest on LVAD. INTERVENTIONS: It took 50 minutes to change the battery, then the patient has become ventricular fibrillation; hence, we introduced extracorporeal membranous oxygenation and defibrillated the patient. After the sinus rhythm was restored, the LVAD started working uneventfully. OUTCOMES: The patient became brain dead. LESSONS: There are several difficulties in treating these patients. First, hemodynamic collapse is difficult to diagnose. Second, chest compression for LVAD implanted patients remains controversial. Third, education to first responders who are not familiar with LVAD are not enough. Appropriate education for those issues is needed.