4. E.M.S. went to bed about 11 PM after a busy evening of entertaining friends and family. He was awakened at 2 AM with chest pain that radiated to his left shoulder, arm and fingers. His son took him to the emergency room, where he was immediately given oxygen by mask and nitroglycerin. His chest pain was relieved in about 39 minutes. An ECG revealed evidence of myocardial ischemia but no evidence of amyocardial infarction. He was admitted to the cardiac intensive unit for further evaluation.a. What's the most likely cause of the pain (what's the name of the condition and what causes it)?

b. What kind of medication is nitroglycerin and why does it help to relieve the pain? What are other treatment options for this condition?

c. Define the underlined terms.