A 39-year-old man comes to the emergency department with anterior chest pain. He had felt well until the pain developed 4 days ago. The patient says the pain is sharp and makes it difficult to take a deep breath. Since yesterday, he has also felt out of breath. Medical history is unremarkable. The patient's father died of a heart attack at age 52, and his mother suffers from rheumatoid arthritis. He does not use alcohol or tobacco. Temperature is 37.4 C (99.3 F), blood pressure is 112/65 mm Hg, and pulse is 103/min and regular. Bedside ultrasound examination demonstrates a moderate pericardial effusion. Which of the following is the most likely cause of this patient's current condition?
Acute pericarditis | |
Etiology |
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Clinical features |
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SLE = systemic lupus erythematosus. | |
This patient most likely has acute viral pericarditis; viral infection is the most common cause of pericarditis and many viruses (eg, adenovirus, coxsackievirus, echovirus, influenza virus) have been implicated. Because the viral infection often cannot be confirmed, presumed viral pericarditis is sometimes referred to as idiopathic. Pericarditis typically presents with substernal pleuritic chest pain that may radiate to the bilateral scapulae posteriorly. The pain is typically worse when lying flat and improves with sitting up and leaning forward. Fever is common but often not present.
Cardiac auscultation in acute viral pericarditis classically reveals a triphasic pericardial friction rub (occurring during atrial systole, ventricular systole, and early ventricular diastole); however, the rub may be absent, especially in the presence of significant pericardial effusion. Mild to moderate-sized pericardial effusion is common and can rarely lead to cardiac tamponade. ECG characteristically demonstrates diffuse ST elevation caused by inflammation of the ventricular myocardium.
(Choice A) Autoimmune disease (eg, systemic lupus erythematosus, rheumatoid arthritis) is a potential cause of pericarditis, but it is less common than viral pericarditis and is less likely in the absence of a personal history of autoimmune disease (pericarditis is only rarely the presenting manifestation of autoimmune disease).
(Choice B) Myocardial infarction due to coronary artery disease (CAD) can lead to peri-infarction pericarditis (a localized reaction to transmural myocardial necrosis) within 2-4 days or to Dressler syndrome (an autoimmune response to infarction-induced antigens) within weeks to months. Despite a family history of CAD, myocardial infarction is relatively unlikely in this man age <40.
(Choice C) Gram-positive cocci (eg, Staphylococcus aureus, Streptococcus pneumoniae) in rare cases can cause pericarditis (purulent pericarditis) via direct extension of pneumonia or hematogenous bacterial spread. Affected patients are typically quite ill and present with high fever and sepsis.
(Choice D) Malignant pericarditis can occur in the setting of metastatic cancer (eg, lung cancer, breast cancer); however, it is less likely to present with pain and inflammation and more likely to present with symptoms of fluid accumulation (ie, dyspnea due to subacute cardiac tamponade). Malignant pericarditis is also relatively uncommon compared to viral pericarditis and less likely in this relatively young man.
Educational objective:
Viral infection is the most common cause of acute pericarditis. It causes a fibrinous or serofibrinous pericarditis that is often characterized by pleuritic chest pain, a friction rub on cardiac auscultation, diffuse ST elevation on ECG, and mild to moderate-sized pericardial effusion.