Background: Although very rare, cardiac sarcoma is the most common malignant cardiac tumour. Cardiac tumours may present with constitutional symptoms and this can lead to delayed diagnosis.
Case presentation: A woman in her late twenties was admitted to the acute psychiatric ward with suspected depressive psychosis. Although she presented with insomnia, auditory hallucinosis and paranoid delusions, her main symptoms were dyspnoea, tachycardia and exhaustion. She was discharged after 17 days and admitted directly to the medical ward for further examination. A thorough somatic examination, including diagnostic imaging, revealed a tumour in the left atrium obstructing the mitral ostium in the diastole, resulting in orthopnoea. She had urgent cardiac surgery and the histology was consistent with an intimal sarcoma.
Interpretation: This case illustrates a rare disease presenting with atypical symptoms. Her psychiatric symptoms resolved after surgery and oncologic treatment of her cardiac tumour.