What is Cardiac Myxoma?
Cardiac myxoma refers to a benign (non-cancerous) mass of tissue formed due to uncontrolled growth of heart cells. If left untreated, it could develop into a malignant tumour that can spread to other parts of your body.
Anatomy of the Heart
Your heart is located between your lungs slightly left of your breastbone (sternum) under the rib cage. It is enclosed by a double-layered membrane called the pericardium which acts as a shock absorber and provides protection to your heart. Your heart is made of strong flexible muscles. The inside of your heart is hollow and four-chambered, which are the atria: the two top chambers, which receive blood from your veins; and the ventricles: the two bottom chambers, which pump blood into your arteries.
As blood exits each chamber of your heart, it passes through a valve. There are four heart valves within your heart: aortic valve, mitral valve, tricuspid valve, and pulmonary valve. These valves prevent blood flow in the wrong direction.
Common Sites for a Cardiac Myxoma
A cardiac myxoma usually develops in the left atrium in the majority of cases, followed by the right atrium, the ventricles and the valves of your heart. Sometimes multiple myxomas may develop at different sites in your heart at the same time.
Usually, cardiac myxomas do not spread (metastasise) to other parts of the body. However, sometimes they may metastasise to the brain, breastbone, spinal column, pelvis and shoulder blade (scapula).
Causes of a Cardiac Myxoma
Common causes of a cardiac myxoma include:
- Chromosomal abnormalities
- Herpes simplex virus 1 infections
Symptoms of a Cardiac Myxoma
Cardiac myxomas may be asymptomatic if less than 4 cm in size. The symptoms of a myxoma are based on the size, location, and mobility of the myxoma.
The common symptoms of a cardiac myxoma include:
- Embolism: Blockage in an artery due to air entrapment or blood clot
- Dyspnoea: Breathing discomfort marked by shortness of breath or breathlessness
- Palpitations due to irregular heartbeat (arrhythmia)
- Oedema in the lower limbs
- Pulmonary oedema: Your lungs fill with fluid
- Angina: chest pain
- Hepatomegaly (enlarged liver)
- Syncope: Temporary loss of consciousness due to inadequate blood flow to your brain
- Cough, that may contain blood
The other symptoms include fatigue, fever, muscle, and joint pain and weight loss.
Diagnosis of a Cardiac Myxoma
Your doctor will enquire about your symptoms and recommend a transthoracic and transesophageal echocardiography for confirmation of cardiac myxoma. In these diagnostic tests, sound waves will be passed through your food pipe (oesophagus) and thoracic region to detect the cardiac myxoma.
Treatment of a Cardiac Myxoma
Cardiac myxoma is usually treated through surgery that involves resection (removal) of the myxoma from your heart.
Surgical Procedure to treat a Cardiac Myxoma
You will be placed in the supine position on your back and administered general anaesthesia. Your body temperature will be lowered (hypothermic) and you will be put under cardioplegic cardiac arrest using a cardiopulmonary bypass machine. It is a device that provides blood and oxygen to your body when the heart is stopped for surgery. Your surgeon will make an incision in your chest at the site of the myxoma and use visualisation devices during your surgery to view and remove the tumour. For complete tumour removal, your surgeon may remove part of the septum. This would create a void which will be closed using a Dacron or pericardial patch. The incision is then closed with sutures.
Sometimes, when tumours are attached to the valves of your heart, your cardiac surgeon may also perform a valve repair surgery wherein the valve may be replaced using a graft, or an artificial prosthesis may be implanted in your heart.
Risks Associated with Cardiac Myxoma Surgery
Cardiac myxoma surgery is a safe procedure, yet there is a minimal risk of complications including:
- Irregular heartbeat: Supra-Ventricular arrhythmia
- Heart dysfunction
- Chance of recurrence in some people