Review Question - QID 214305

A 66-year-old man presents to the emergency department with chest pain, shortness of breath, and diaphoresis that started suddenly 25 minutes ago. His symptoms are ongoing upon arrival. The patient has a past medical history of diabetes, peripheral vascular disease, smoking, and IV drug abuse. The patient is given several medications and is taken to the cardiac catheterization lab. He is subsequently admitted to the medicine floor. The patient is recovering well; however, on day 4 of his hospital stay, he complains of sudden onset chest pain. His temperature is 99.3°F (37.4°C), blood pressure is 52/38 mmHg, pulse is 177/min, respirations are 34/min, and oxygen saturation is 99% on room air. The patient becomes unresponsive, and nursing is unable to palpate a femoral pulse. An ECG is performed as seen in Figure A. Which of the following is the most likely diagnosis?