Not so Innocent Murmurs
Jake is a lovely spaniel in his twilight years. He has had a heart murmur for a long time that up until fairly recently wasn’t causing him any problems. We have monitored him regularly, especially when he comes for his annual health examinations. The murmur has got progressively louder and eventually Jake developed a cough.
Jake’s heart murmur is caused by a leaky valve on the left side of his heart (the mitral valve). Many dogs develop little ‘vegetative’ growths on the valve as an aging change. This is called endocardiosis. The changes prevent the valve from sealing properly with each heart beat. The left side of the heart pumps oxygenated blood that it has received from the lungs around the body.
In Jake’s case some of the blood from the left ventricle is pushed back through the leaking valve towards the lungs increasing the pressure in the circulation there. Not enough blood is pumped forwards so the heart struggles to supply the body with enough blood. The extra pressure in the circulation in the lungs makes the right side of the heart have to work harder too. Also, because of the extra pressure, some fluid is forced out into the lungs. It is this fluid which was causing Jake to cough.
So Jake has congestive cardiac failure and is being treated with a combination of cardiac drugs:
Furosemide and spironolactone are diuretics which improve the circulation in the kidneys and help remove excessive fluid.
Pimobendan (Vetmedin) is a drug which acts directly on the cardiac muscle to help it to beat harder and better (improved contractility).
Benazepril (Fortekor) is a type of drug called an ACE inhibitor. It helps to lower blood pressure, improve the circulation in the heart, lungs and kidneys, and increase the amount and ease with which blood gets back to the heart to be pumped, so it significantly reduces the workload on the heart.
The X Rays of Jake’s chest below show that is heart is enlarged (like any muscle the heart enlarges as it is given more work to do). They also show little fluffy clouds of fluid around the base of the heart, some congestion in blood vessels and some age related changes affecting the airways. The wind pipe and main bronchi extending from it can be clearly seen. The enlarged heart may be putting some pressure on the bronchi which could also be exacerbating the cough.
With the right treatment, monitoring and care Jake and other dogs like him can lead a good and long life.
There are many causes as to why dogs or cats may cough so it is wise to see the Vet if your pet develops a persistent cough.
Most heart murmurs in dogs and cats are innocent and don’t cause problems. But it is always wise to monitor them in case anything changes.
Symptoms of heart disease can be any of many: exercise intolerance, ‘fainting’ episodes, lethargy, coughing, pot belly, difficulty breathing, increased breathing rate, blue gums etc. If your pet develops any of these symptoms you should seek advice.
We recommend at least Annual health examinations for all pets. Among other things we always listen to their chest to detect any evidence of heart or lung disease. Many of the conditions we come across are far more treatable and have better outcomes if we are able to provide treatment at an early stage.
Our Nurses also run a FREE SENIOR CLUB for older pets where we can identify a range of problems and where expert advice is given for the care of your loved ones.