Cardiac tumours, an overview of benign and malignant neoplasms

By Cristiano Antonino Last updated Jun 4, 2023

Although not much is said about them, there are also cardiac tumours: they are extremely rare, with an incidence of around 0.2% compared to other oncological cases

Cardiac tumours are also divided into benign and malignant, like primary tumours; metastatic tumours are always malignant.

Primary cardiac tumours develop in the heart muscle, and are generally benign

They appear in 1 in 2000 individuals.

Metastatic cardiac tumours will develop in another organ and extend to the heart; these tumours tend to start in the lungs and are always malignant.

In general, however, benign cardiac tumours occur more frequently than malignant ones.

Cardiac myxomas account for the vast majority of these

Myxomas are located in the right and left atrial cavities, but occur more frequently in the left atrium and are called atrial myxomas.

Myxomas are generally diagnosed around the age of 50. Mostly women are affected, with an incidence four times higher than men.

This type of benign tumour arouses curiosity not only because of their high clinical danger but also because their origin remained unknown until a few years ago.

It was discovered that they originate from modified heart stem cells that lead to the formation of myxoma.

The myxoma has the shape of a roundish or villous mass that tends to be gelatinous with a sessile or pedunculated implantation base, occupies the cavity of the atrium in which it is located and is called atrial myxoma.

Atrial myxoma is generally considered a benign neoplasm as it has a low level of local invasiveness and does not present metastases.

This benign tendency may lead to an underestimation of the clinical risk that may be present for the patient.

Benign tumours can be as deadly as malignant ones if they interfere with cardiac function

Due to their anatomical position, atrial myxomas can trigger various clinical pictures to the point of becoming lethal because of the way they originate and the consequences related to blood flow.

It may happen that the mass may go undetected and the patient remains asymptomatic due to the small size of the mass; it will be detected in such cases following ‘occasional’ echocardiography.

As the size of the mass increases, interference with the heart’s activity will begin to occur.

The myxoma may come to partially occlude the mitral valve, there will then be symptoms similar to mitral valve stenosis causing respiratory difficulties; in the diastolic phase it may be carried away by the blood flow and may, depending on its size, obstruct the atrioventricular orifice causing a blockage of the circulation and thus causing fainting.

In more advanced stages, there may be fragmentation of the mass or there may be thrombi that overlap the tumour, with the pressure of the heart may enter the circulation causing peripheral occlusions.

Symptoms will include weakness and exhaustion, loss of appetite and weight loss, anaemia and fever.

Diagnosis will be made with trans-thoracic echocardiography, and with CT and MRI, optimal diagnoses will be made in malignant tumours.

With the cardiac echocolordoppler, one will see the size of the tumour, the lesions and their impact on the blood flow.

It will then be possible to detect the obstruction that the lesion will cause to the atrioventricular valves by calculating the transvalvular gradients and indirect parameters that will give us the information we need for the surgical procedures and, above all, the timing of the operation.

The treatment of myxomas is mainly surgical, and will be decisive in cases of benign tumour with myxoma

The operation will be performed under general anaesthesia and using extracorporeal circulation; the heart will be temporarily stopped so that the surgeon can access the cardiac cavity containing the mass.

The myxoma will occur predominantly in the left atrium, so a left atriotomy will be used; the atrium will be incised by opening it, and the mass will be removed, ensuring that all visible tissue is removed.

Once the mass has been removed, the atrium will be closed, the air in the cardiac cavities will be expelled and the patient will be disconnected from the extracorporeal circulation machine when the heart has resumed its pumping activity independently.

The prognosis is excellent and the risks of recurrence very low.

Once the mass has been removed, the patient will not need to undergo any treatment and will be able to return to his normal daily activities.