A myocardial tumour is a type of heart tumour that is most commonly found in older dogs. This type of tumour can be benign or malignant, and it's not yet understood why some dogs develop a myocardial tumour. Any breed of dog can develop this condition, but larger breeds, such as Labradors and German Shepherds, seem to be at an increased risk.

Symptoms Of A Myocardial Tumour

Common symptoms of a myocardial tumour include heart murmurs, heart rhythm abnormalities, lethargy, weakness, laboured breathing and loss of appetite. Your dog may become intolerant to even mild exercise and develop a persistent cough. A myocardial tumour can lead to sudden collapse, rapid weight loss and heart failure, which can be fatal.

Diagnosing And Treating Myocardial Tumours

Your vet will diagnose your dog using a combination of factors including your dog's symptom presentation, health history, physical exam and diagnostic testing. Blood tests will be carried out to check for inflammation and infection, and diagnostic imaging, such as an ultrasound or X-ray, will be required to allow your vet to see your dog's heart and determine if any abnormal growths are present. An electrocardiogram (ECG) is often used to determine how your dog's heart is functioning and measures the electrical currents that are generated each time your dog's heart beats. When a myocardial tumour is found during the diagnostic process, your vet may want to obtain a tissue sample from the tumour to determine whether it's benign or malignant. This is usually done using keyhole surgical techniques.

Regardless of whether a myocardial tumour is malignant or benign, treatment will involve surgery to remove it. Dogs with benign tumours will require no further treatment, but it can take some time for them to regain their strength after heart surgery. Your vet will provide information on how to support your dog as they recover, and this may include making dietary changes, altering your dog's exercise routine and making changes in their living environment to support a calm and peaceful recovery period. Dogs with a malignant tumour will require additional treatment, such as chemotherapy or radiation therapy, to try and kill off the cancer cells that have spread to other parts of their body. These treatments can be particularly hard on older dogs and it's not always possible to obtain remission. As with all tumours, early treatment tends to provide the best chance for a full recovery.

If your dog has symptoms associated with a myocardial tumour, or if you have any concerns about their heart health, make an appointment with a veterinary surgeon.