31.A 62-year-old woman presents to the ED with general weakness, short-
ness of breath, and substernal chest pain that radiates to her left shoulder.
Her BP is 155/80 mm Hg, HR is 92 beats per minute, and RR is 16 breaths
per minute. You suspect that she is having an acute MI. Which of the fol-
lowing therapeutic agents has been shown to independently reduce mortal-
ity in the setting of an acute MI?
a. Nitroglycerin
b. Aspirin
c. Unfractionated heparin
d. Lidocaine
e. Diltiazem
32.A 22-year-old college student went to the health clinic complaining of
a fever over the last 5 days, fatigue, myalgias, and a bout of vomiting and
diarrhea. The clinic doctor diagnosed him with acute gastroenteritis and
told him to drink more fluids. Three days later, the student presents to the
ED complaining of substernal chest pain that is constant. He also feels
short of breath. His temperature is 100.9°F, HR is 119 beats per minute, BP
is 120/75 mm Hg, and RR is 18 breaths per minute. An ECG is performed
revealing sinus tachycardia. A chest radiograph is unremarkable. Labora-
tory tests are normal except for slightly elevated WBCs. Which of the fol-
lowing is the most common cause of this patient’s diagnosis?
a. Streptococcus viridans
b. Staphylococcus aureus
c. Coxsackie B virus
d. Atherosclerotic disease
e. Cocaine abuse
Chest Pain and Cardiac Dysrhythmias 17