Did you know dogs can also suffer from heart problems? Here, we focus on the acquired heart diseases of dogs.
–by Col Virendra Kumar
Contrary to popular belief, heart diseases and associated problems in dogs are quite common. However, specific diagnosis of the problem may not be easily available to pet parents in certain cases because of non-availability of specialised diagnostic facilities. Specialisation will emerge in Veterinary profession as well as the new trends in pet parenting emerge and customer expectation grows. There can be many potential causes of heart diseases. Any form of heart disease, may lead to a clinical situation in which heart fails to respond to the demand of the body, popularly known as ‘Heart Failure’.
Types of heart diseases
Heart diseases can be congenital or acquired. Congenital heart disease is present at the time of birth. Acquired heart diseases are those which results due to wear and tear of the heart, with or without infection or injury. Middle aged or old dogs suffer from acquired heart disease. Vulnerability varies from breed to breed and dog to dog depending upon lifestyle.
Acquired heart diseases
Diseases of the heart which occur as a result of wear and tear of the heart (Acquired Heart Diseases) include:

  • Valvular disease-Though all the breeds are susceptible, smaller breeds show more vulnerability. Mitral valve is commonly affected.
  • Myocardial diseases- Heart muscles are affected, common in larger breeds. Also called cardiomyopathy.
  • Cardiac Arrhythmias- When electrical system of the heart is affected and abnormal heart beats are heard (cardiac murmur).
  • Pericardial disease- When outermost layer of the heart is affected, it puts the restriction on function of heart beat.
  • Infections – Especially Parvo virus infection.
  • Injury- Specially due to Heart worm infestation.

The symptoms produced may be identical and differential diagnosis is a must. Overall, it is the vet’s clinical judgment to deploy the diagnostic tools.
Medications to manage heart disease
There are many options available with the vet who will decide based on the diagnosis, overall clinical profile of the dog and severity of the disease.
Diuretics: These are generally used to remove the extra fluid that results from suboptimal heart function (heart failure).
ACE inhibitors (Antiotensin-converting enzymes: These cause vasodilatation and thus results into lower blood pressure. It can be used to monitor hypertension.
Vasodilators and Vasoconstriction drugs: Depending upon the requirement, doctor can prescribe these.
Inotropes: These increase the intensity of heart contraction.
Medications that reduce blood clotting: These are used to prevent thromboembolism which results into blockage of artery thus preventing circulation.
Nutritional supplements: Many of the heart conditions respond to supplements such as Taurine or L-carnitine. Anti-oxidants such as coQ10 are also used by some. It is basically vet’s discretion and he must be consulted. Incidence of acquired heart disease is increasing now though authentic data may not be available for India. Geriatric patients are more vulnerable as wear and tear of the heart increases in old age. Life style changes are required along with the correct diagnosis to institute a correct treatment regimen so that your dog can lead the normal life.
Diagnosis will be very critical and veterinarian has to play a critical role in diagnosis and in prescribing the correct line of treatment.
Physical examination: of the patient is most critical. Presence of fluid in lungs or abdomen can be found out. Cardiac murmur can be heard with auscultation. Vet may look for coughing by the dogs along with other associated symptoms.
X-Ray: It is another important tool available with the Vet which can help in diagnosis based on increased shape and size of the heart, and increased size of the blood vessels. It can also substantiate the presence of fluid in abdominal cavity and in lungs, leading to the diagnosis of heart failure. Presence of ascites (fluid in abdominal cavity) can also be substantiated with X-Ray , also seen in cases of heart failure.
Echocardiogram: Ultrasonic examination is another very important tool for the confirmatory diagnosis of all the heart diseases. ECG is for recording the electrical activity of the heart especially for abnormal heart beats or arrhythmias.
Other tests: Supporting evidence can be through thyroid testing and with antibiotic sensitivity test, depending upon the clinical condition of the dog. Blood level of Taurine can also help in diagnosis of certain heart problem.
(Col Virendra Kumar, MSD Animal Health)