Large Left Atrial Myxoma - A Tumour of the Heart

A 71 year old lady, a known case of diabetes mellitus with history of episode of syncope (temporary loss of consciousness usually related to insufficient blood flow to the brain) came to our hospital after being referred from another medical centre after first aid management. She was unconscious when she had reached the medical centre where she was managed initially. When she arrived at our hospital, she was conscious, had mild fever of unknown origin, breathlessness and fatigue. She was physically examined at the emergency (ED) and referred to the department of cardiology & cardiothoracic surgery for further analysis. We performed almost all necessary cardiac procedures of which echocardiography revealed a left atrial myxoma.

A left atrial myxoma is a benign tumour which is relatively rare but can have significant clinical implications. A cardiac myxoma is the most common tumour originating from the heart and a majority of the time the tumour is attached to the inter-atrial septum by a relatively thin stalk. While it can be located in the right atrium or the ventricles, the most common location for a cardiac myxoma is the left atrium. The tumour can grow large enough to obstruct mitral valve inflow causing hemodynamic changes similar to mitral valve stenosis.

Pathologically, the tumour originates from multipotential mesenchymal cells. Approximately 20% of cardiac myxomas arise as part of a genetic syndrome. The diagnosis of the myxoma is made by echocardiography, which is capable of visualising the tumour directly. Hence after finding out her problem, we decided to perform a coronary angiography (CAG) to check her coronaries (arteries which supply blood to the heart). All her coronaries were normal as per the CAG findings. The next step was to excise the large atrial myxoma via open heart surgery.

The patient's family members were informed about the necessity for surgical excision of the tumour as it may have caused severe symptoms and even heart failure due to mitral inflow obstruction. We performed the surgery after taking informed consent from the family members and the patient, During the surgery, we found that her heart and chambers were normal in size.

The myxoma was excised intact along with adjoining septum through left atrial approach. The size of the tumour (myxoma) was 5 cm x 6 cm, which is very large in terms of appearance in and around the heart. No other mass was seen. Her mitral valve was structurally normal. The mass excised was sent for histopathological examination. Post-operative period was uneventful and she was discharged in a haemodynamically stable condition on the 9th day after surgery. For knowledge, we would like to share a fact that, approximately 75% of total cardiac tumours occurring are found to be benign. Thankfully this case was no different and her histopathological findings showed that the tumour/myxoma was benign.

The symptoms of a cardiac tumour are non specific. We have seen people showing different symptoms and hence diagnosis of the same is very challenging. It was a combined effort of the team at the ED and also the cardiac team which made the diagnosis of this case so easy and accurate in a very short span of time.