Question of the Week

For August 23, 2016

A 68-year-old woman presents for follow-up 3 weeks after experiencing an anterior ST-segment elevation myocardial infarction and receiving a drug-eluting stent in her proximal left anterior descending artery.

She has been participating in cardiac rehabilitation and was doing well until 6 days ago, when she started feeling sharp left-sided substernal chest pain. The pain waxes and wanes unpredictably throughout the day and is worse with inspiration and on lying down. She also reports an episode of subjective fever yesterday.

She has systolic dysfunction (left ventricular ejection fraction, 42%), hypertension, and hyperlipidemia. Her medications are aspirin 81 mg, prasugrel 10 mg, atorvastatin 80 mg, extended-release metoprolol 50 mg, lisinopril 10 mg, and furosemide 20 mg, each taken once daily.

She has a low-grade fever of 37.7ºC. Her heart rate is regular at 58 beats per minute, her blood pressure is 128/76 mm Hg, and her oxygen saturation is 98% while she is breathing ambient air. She has no jugular venous distention. Her lungs are clear to auscultation. There are no murmurs, rubs, or gallops. She has no lower-extremity edema.

An electrocardiogram is obtained (figure).

Laboratory results are as follows:

Patient value

Reference range

Creatine kinase (U/liter)

136

40–150

Creatine kinase MB isoenzyme (ng/mL)

3

0–7

Troponin T (ng/mL)

0.04

0–0.1

Brain-type natriuretic peptide (pg/mL)

376

<167

Which one of the following next steps is most appropriate for this patient?

Hospitalize the patient and infuse unfractionated heparin
Order CT of the chest with a pulmonary embolism protocol
Initiate treatment with colchicine and full-dose aspirin
Initiate treatment with high-dose prednisone
Repeat left heart catheterization