This is the commonest primary cardiac tumour. A myxoma usually develops in the left atrium and is a polypoid, gelatinous structure attached by a pedicle to the atria septum. The tumour may obstruct the mitral valve or may be a site of thrombi that then embolize. It is also associated with constitutional symptoms: the patient may present with dyspnoea, syncope or a mild fever. The most important physical signs are a loud first heart sound, a tumour ‘plop’ (a loud third heart sound produced as the pedunculated tumour comes to an abrupt halt), a middiastolic murmur, and signs due to embolization. A raised ESR is usually present.
The diagnosis is easily made by echo cardiography because the tumour is demonstrated as a dense spaceoccupying lesion. Surgical removal usually results in a complete cure.
Myxomas may also occur in the right atrium or in the ventricles. Other primary cardiac tumours include rhabdomyomas and sarcomas.