The medical term for enlarged heart in dogs is dilated cardiomyopathy or DCM. It is a condition of the cardiac muscle which prevents the heart from functioning properly. The condition is characterized by enlargement of both the lower and upper chambers of the heart, wherein one side is more severely affected as compared to the other side. Enlargement of the lower chamber or the ventricle results in limited ability of the heart to supply blood to the lungs, eventually leading to deterioration of the body.Decreased supply of blood to the lungs causes elevated levels of fluids to deposit in the lungs. An enlarged heart in dogs will lead to cardiac overload, ultimately resulting in congestive cardiac failure.
The occurrence of enlarged heart in dogs increases with older age. It typically affects dogs in the age group of 4 to 10 years old. Enlarged heart in dogs is comparatively more widespread in some breeds like the Doberman Pinscher, Scottish Deerhound, Boxer, Irish Wolfhound, Saint Bernard, Great Dane, Cocker Spaniel, and Afghan Hound.
Symptoms of enlarged heart in dogs
A number of dogs with enlarged hearts generally do not show any visible signs of distress or discomfort and mostly remain unaffected by the severe cardiac condition. However, when there are outward symptoms of enlarged heart in dogs, then the affected dogs may suffer from respiratory problems which can be quite uncomfortable, frightening, or severely painful.
The symptoms of clinical cases of enlarged heart in dogs are similar to those observed in cases of cardiac arrhythmias and congestive heart failure. Some of the common symptoms experienced by the affected dogs are as follows:
- Problems in breathing or respiratory discomfort
- Coughing which is more common during nighttime. The sputum may or may not contain blood
- Rapid or fast breathing
- Abnormal discharge from the nose
- Cardiac murmurs or irregular sounds from the heart
- Loss of appetite
- Irregular sounds from the lungs or abnormal breathing sounds. It is generally caused due to accumulation of fluid around the lungs and heart
- Arrhythmia or anomalous cardiac rhythms
- Intolerance to exercise. The affected dog may tire easily
- Marked and rapid loss of weight
- Fainting or loss of consciousness
- Swollen or distended abdomen
- Sudden fatality
Causes of enlarged heart in dogs
- The exact cause of enlarged heart in dogs is currently not known. Nutritional deficits in carnitine or taurine have been seen to be associated with increased instances of enlarged hearts in some breeds such as Cocker Spaniels and Dobermans.
- Research and studies have also indicated that certain breeds have a genetic predisposition to the disorder. In a majority of breeds, the male dogs are more vulnerable to the condition as compared to female dogs.
Diagnosis of enlarged heart in dogs
Enlarged heart in dogs can be diagnosed after a complete physical inspection of the heart. Also, a number of other tests also need to be carried out to confirm diagnosis of the condition, and to rule out other possible causes.
- An EKG or electrocardiogram will help detect presence of rapid heartbeats or ventricular tachycardia, and atrial fibrillation.
- Radiographic imaging can help detect the occurrence of fluid in the lungs, as well as atrial and left ventricular enlargement
- An echocardiograph of enlarged heart in dogs will detect an enlarged left atrial and left ventricular, and decreased contraction capability
- An ultrasound of the heart with the aid of echocardiograph imaging is essential to conclusively diagnose the presence of enlarged heart in dogs. This diagnostic test checks the size of the heart as well as the contraction capability of the ventricular
Treatment of enlarged heart in dogs
The treatment of enlarged heart in dogs is majorly aimed at enhancing the functionality of the heart and on managing and curing the signs of congestive cardiac failure.
- Medications may be recommended to improve cardiac contraction and to lower the fast heartbeats.
- Medications like vasodilators which help in dilation of the blood vessels and aid in the effective supply of blood from the heart are also generally used to treat enlarged heart in dogs.
- Diuretics may be administered to manage the buildup of fluid in the lungs
- Prolonged hospitalization of affected dogs is usually not necessary, except in instances where the dog is suffering from a severe case of the disease.
Prognosis of enlarged heart in dogs
The prognosis of enlarged heart in dogs is quite poor and a majority of the affected dogs tend to survive for 6 to 24 months. The vet will inform the owner about the chances of a pet’s survival after studying the progression of the condition post the initial diagnosis.
Pet owners need to take their dogs for regular checkups after the initial treatment. During such follow-up treatments, vets will carry out a variety of tests to measure the progress of the affected dog. Pet owners also need to keep a constant lookout for abnormal symptoms such as exhaustion, labored breathing, and others which may indicate a relapse.