Epikarditis

Epikarditis, or epicarditis, is inflammation of the epicardium, the outer layer of the heart that covers the myocardium and forms the visceral layer of the serous pericardium. It is relatively rare and can occur as an isolated process or as part of broader inflammation of the pericardium (pericarditis) or myocardium (myocarditis).

Causes include infectious agents, most commonly viruses, but also bacteria, fungi, and parasites; autoimmune or inflammatory diseases such as systemic lupus erythematosus or vasculitis; postinfarction or post-surgical inflammatory responses; and drug- or radiation-induced injury. In many cases, the exact cause remains unidentified.

Clinical features are variable. Chest pain that is pleuritic and may worsen with deep inspiration or lying flat can occur, sometimes with fever and malaise. Physical examination may reveal a friction rub. If epicardial inflammation extends to the myocardium or if a large pericardial effusion develops, symptoms of heart failure or arrhythmias can appear.

Diagnosis relies on clinical assessment supplemented by laboratory tests and imaging. Electrocardiography may show changes compatible with pericarditis; inflammatory markers such as C-reactive protein may be elevated. Cardiac troponin can be raised if myocarditis is present. Echocardiography assesses heart structure and effusion; cardiac MRI can demonstrate epicardial inflammation and help distinguish epicarditis from other conditions.

Treatment targets the underlying cause and supportive care. Nonsteroidal anti-inflammatory drugs and colchicine are commonly used; corticosteroids are reserved for autoimmune etiologies or refractory cases. Infections require antimicrobials. Large effusions or signs of tamponade may require drainage. Most isolated epicarditis improves with appropriate therapy.

Prognosis is generally favorable when the condition is isolated and promptly treated, but recurrence can occur, and progression to constrictive pericarditis or concurrent myocarditis warrants careful follow-up.