Left atrial tumour mimicking pulmonary embolism

Primary cardiac tumours have been described as great imitators. They are rare, and clinical presentations are diverse. Diagnosis is usually made by two-dimensional echocardiography. The present case report describes a case where a left atrial fibrosarcoma eluded diagnosis by echocardiography, and was eventually demonstrated by computed tomography. Management was complicated by the presence of persistent mismatch demonstrated by ventilation-perfusion lung scans. The likely mechanism underlying this phenomenon is discussed.