Review Question - QID 216637

A 55-year-old man presents to the emergency department after fainting while moving furniture. He states that he has been working in a hot, humid attic all day and forgot his water bottle. He felt dizzy when standing up and then fainted and was unconscious for roughly 1 minute. He awoke at his neurologic baseline afterwards. The patient has a history of hypertension being managed by his primary care doctor. His temperature is 98.7°F (37.1°C), blood pressure is 149/82 mmHg, pulse is 86/min, respirations are 15/min, and oxygen saturation is 99% on room air. Physical exam reveals a diaphoretic man. He demonstrates an unremarkable cardiopulmonary exam. The patient walks with a steady gait and his neurologic exam is non-focal. An ECG is performed as seen in Figure A. The patient is given 2 liters of oral fluids and feels back to his baseline. Which of the following conditions is most likely to occur in this patient based on his current history and ECG?