Chest Pain in 74-Yr-Old Man

Diagnosis

The patient experiences complete relief of his chest pain after a single dose of sublingual nitroglycerin. On physical examination he no longer has tachycardia and does not appear to be in distress. Cardiac monitoring now shows normal sinus rhythm. Portable chest x-ray is obtained and is reported as normal except for hyperinflated lung fields.

At this time, which of the following is the most likely diagnosis. (You may select more than one option.)