Acute Myocarditis

A 26-year-old woman is hospitalized because of a 7-day history of increasing shortness of breath. Two weeks ago, she had flu-like symptoms of fever, muscle aches, and chest pain, which have since resolved. She does not take any medications.

On physical examination, temperature is 37 °C (98.6 °F), blood pressure is 120/79 mm Hg, and heart rate is 100/min and regular. The lungs are clear. Cardiac examination shows a normal S1 and S2. Echocardiogram shows normal-sized ventricles, decreased systolic function (left ventricular ejection fraction, 40%) that is global and most severe in the anterior wall, and no significant valvular abnormalities. Coronary angiography discloses no evidence of coronary artery disease.

Which of the following is the most appropriate next step in treating this patient?
A Azithromycin
B Enoxaparin
C Ibuprofen
D Lisinopril
E Prednison

Key Point
Therapy for acute myocarditis generally consists of standard care for heart failure tailored to the severity of the myocarditis.

Answer and Critique (Correct Answer = D)

This patient's presentation, including a viral prodrome, chest pain, symptoms and findings of heart failure in the absence of significant coronary artery disease, is consistent with acute myocarditis, which can range in presentation from asymptomatic to acute cardiogenic shock. Wall motion abnormalities on echocardiography can be regional or global during acute myocarditis. There is no specific treatment for acute myocarditis other than supportive care and the usual treatment for heart failure, including an angiotensin-converting enzyme inhibitor such as lisinopril, in the absence of contraindications.

The patient's normal blood pressure is not consistent with a serious infection, such as sepsis, and in the absence of other, more concrete evidence for infection, antibiotics are not indicated. The results of the coronary angiography rule out acute coronary syndrome, and therefore enoxaparin is not indicated. Although myocarditis is characterized by inflammation, there is no proven role for ibuprofen or corticosteroids for treatment.
Bibliography

1. Magnani JW, Dec GW. Myocarditis: current trends in diagnosis and treatment. Circulation. 2006;113:876-90. [PMID: 16476862]