10-19-2008, 02:41 AM
A 68-year-old male is brought to the emergency department because of substernal chest pain. On
interview, the patient reports having a past myocardial infarction 5 years ago. He has typical anginal
pain, when climbing stairs and when lifting heavy objects, that is relieved by taking nitroglycerin tablets
and resting. In the last week, however, his anginal symptoms have become more frequent and occur
when walking even short distances. In the hospital, the patient continues having chest pain over his left
side accompanied by shooting pain in his left arm. His blood pressure is160/90 mm Hg, pulse is
109/min, and oxygen saturation is 96%. Physical examination is unremarkable. A chest x-ray is clear
with normal cardiac size. An electrocardiogram shows Q-waves in leads II, III, and AvF and T-wave
inversions in v1-v3. Laboratory studies show a potassium of 3.2 mEq/L, hematocrit of 42%, and initial
cardiac markers are negative. The patient receives oxygen, an aspirin, a beta-blocker, intravenous
heparin, and is placed on a platelet gp IIb/IIIa inhibitor. In addition, he is made pain-free on intravenous
nitroglycerin. A repeat electrocardiogram without pain is unchanged. The most appropriate next step in
management is
A. admission to the hospital and observation for 48 hours
B. coronary angiography
C. emergent coronary artery bypass graft (CABG)
D. intra-aortic balloon pump
E. thrombolysis by administration with tPA