A 63-year-old man with a past medical history of type 2 diabetes, persistent atrial fibrillation (AF), and schizophrenia was brought to the emergency room after being found unconscious on the floor, with bladder and bowel incontinence.Physical examination was unremarkable, and the initial laboratory workup was positive for lactic acidosis, elevated creatine kinase, and hypomagnesemia.During cardiac monitoring performed in the emergency room, a wide complex tachycardia (WCT) was observed on telemetry, and a 12-lead ECG was obtained (Figure 1).What is the electrocardiographic diagnosis of this wide complex rhythm?Please turn the page to read the diagnosis.Figure 1.Twelve-lead ECG obtained immediately after syncopal episode.