Review Question - QID 214293

A 66-year-old man presents to the emergency department for sudden onset right leg pain. He states that it started 1 hour ago and has progressed to numbness in his right lower extremity. The patient was treated for a myocardial infarction 1 month ago and has been compliant with medical care. His temperature is 99.3°F (37.4°C), blood pressure is 142/88 mmHg, pulse is 87/min, respirations are 14/min, and oxygen saturation is 99% on room air. The patient's right lower extremity is cold to the touch and is notably pale. The physician is unable to palpate or Doppler a posterior tibial or dorsalis pedis pulse. The patient is subsequently treated appropriately for his chief complaint and is admitted to the hospital. Which of the following is the most appropriate next step in management?