Refractory ventricular fibrillation caused by caffeine intoxication.

A 30-year-old female with no history of cardiac or systemic disease presented with incessant ventricular fibrillation (VF) after an intake of 12 g of over-the-counter caffeine tablets for a suicidal purpose. Her VF was refractory, and repeated defibrillations were needed to attain a recovery of sinus rhythms. We then performed percutaneous cardiopulmonary support and therapeutic hypothermia to stabilize her circulation and prevent anoxic brain damage, respectively. A blood examination revealed an extremely high concentration of caffeine (172 mg/L). She fully recovered 16 days after her admission. Our findings reveal the potentially lethal arrhythmogenic nature of caffeine. <Learning objective: Several reports have described lethal cardiac events with caffeine intoxication. However, clinical observations on patients with pure caffeine intoxication are extremely rare. Since the pharmacological actions and proarrhythmic mechanism of caffeine are not fully understood, intensive treatment against refractory arrhythmia may have an impact upon the prognosis of patients with caffeine intoxication.>.