Man With Chest Pain and Dyspnea
A 50-year-old man presents to the emergency department (ED) with midsternal chest discomfort. The pain started at 3:00 AM and was 6/10 in intensity; it was relieved by 2 sublingual nitroglycerin tablets. The patient had another episode of chest pain at 11:00 AM, this time with radiation toward his left arm. The pain was 10/10 in intensity and was associated with shortness of breath, nausea, and diaphoresis but no vomiting.
The patient was brought to the ED by ambulance. On the way, bradycardia (40 beats per minute) developed; it was treated with 0.5 mg of intravenous atropine.
The patient has a history of coronary artery disease, type 2 diabetes mellitus controlled with oral medications, hypertension, and hyperlipidemia. He is a current smoker (3 packs per day).
His ECG in the ED is shown here.
Which of the following is the most likely diagnosis?
A. Acute pericarditis
B. Inferior myocardial infarction (MI) with the culprit artery being the left anterior descending artery
C. Inferior MI with the culprit artery being the left circumflex artery
D. Inferior MI with the culprit artery being the right coronary artery proximal to the right ventricular branch
E. Inferior MI with the culprit artery being the right coronary artery distal to the right ventricular branch(Answer and discussion begin on next page.)
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