Pericardial Cyst at the Left Cardiophrenic Angle Mimicking Localized Effusion: A Diagnostic Dilemma.

Pericardial cysts are rare, benign, congenital anomalies of the pericardium, usually located within the right cardiophrenic space, often discovered incidentally during imaging performed for unrelated reasons. They usually do not cause symptoms and are detected by chance. Chest X-ray, echocardiography, and chest computed tomography (CT) or magnetic resonance imaging (MRI) are useful diagnostic tools. Nevertheless, after safe diagnostic, management options include conservative management with follow-up, percutaneous aspiration of the cyst, and excision of the cyst (direct invasive therapeutic approach should be the option only for patients with overt symptoms and indications). We report a case of a large, stable pericardial cyst in an atypical location in a 64-year-old woman.