Incidental finding of a filamentous mass in the left atrium in a patient investigated for endocarditis

A previously fit and well middle-aged woman presented with a 24-hour history of deteriorating breathlessness and rigors. The patient showed signs of acute respiratory distress. She was febrile, tachycardic and had a loud pansystolic murmur at the cardiac apex. A chest radiograph showed right lower zone consolidation, and an ECG showed sinus tachycardia. Blood tests showed raised inflammatory markers with white cell count of 11.8×109/L (normal range 4–10×109/L) and C reactive protein 56 mg/L (normal range 0–10 mg/L). A transthoracic echocardiogram identified severe mitral regurgitation secondary to posterior mitral valve leaflet prolapse with a hyperdynamic left ventricle. Peripheral blood cultures were negative. The …