Montse Rabanal – Veterinary Cardiologist – Veterinary ECG
We should pay particular attention to puppies to evaluate on auscultations the presence of murmurs as most common congenital heart defects present a murmur on the auscultation.
It’s important to evaluate correctly the projection area of the different heart valves, the pulmonary and aortic areal, the cranial area (sometimes well below the armpit), the mitral area (on the sternum and at the left side) and the left side of the tricuspid area. Although identifying the point of maximum intensity of the murmur (PMI) and the type of murmur won’t give a specific diagnosis, it will help us to suspect of a process or another. In this case, the ultimate test must be an echocardiography. It’s important to remember that the clinical symptoms in these cases are very diverse. The disease can be totally asymptomatic or present severe symptoms of heart failure with pulmonary oedema, ascites or episodes of syncope. Normal X-rays won’t discard congenital heart disease.
In large dog breeds, the most common heart disease is dilated cardiomyopathy that may initially present with fatigue, but then evolve into tachyarrhythmia and signs of CHF and low cardiac output. No murmurs usually present unless there’s a dilatation of the valve annulus. X-rays are particularly helpful, but they won’t differentiate cardiac dilation from, for example, a pericardial effusion. Again the echocardiography will provide a definitive diagnosis. Cocker Spaniels also suffer from dilated cardiomyopathy although the disease on them is more benevolent than when suffered by large breeds that have a bad prognosis.
In small breeds, the most common pathology is the degenerative valve disease and it appears with a left apical systolic murmur in dogs from 8-9 years old onwards. The progression of the disease is slow but irreversible, so it’s important a correct monitoring to identify when to start the therapy to delay the onset of more serious signs of CHF. The Cavalier King Charles Spaniel presents this disease very prematurely (even with 2-3 years old).
In cats, the diagnosis of heart disease gets complicated. A heart murmur on auscultations isn’t always related to a heart disease. Alterations on radiographies aren’t always obvious and the disease might be asymptomatic until sudden death or the development of congestive signs, being the most typical the pleural effusion. Again echocardiography is necessary.
They are also some dog breeds predisposed to heart diseases such as Boxers, Dobermans, young German Shepherd and English Bulldog.
Consult other articles at eKuore