Knowing the signs of a heart murmur can help you get your cat to the vet as early as possible for diagnosis and treatment. Here, our Springfield vets share the signs and stages of heart murmurs in cats and the possible treatment options.
What Is A Heart Murmur?
A heart murmur may be heard by your vet when they listen to your cat’s heart. A heart murmur is caused by turbulent blood flow within the heart or the large vessels exiting from the heart. This results in an abnormal noise that can be heard by your vet when listening with a stethoscope. This can leave you wondering if stress can cause a heart murmur in cats and what the life expectancy might be. If your cat is due to have surgery and when the murmur is discovered then you might also question if there are any concerns with heart murmurs in cats and anesthesia. First lets cover the basics about heart murmurs in cats.
The Heart Murmur Grading System
Heart murmurs are assessed and graded according to certain criteria. Grades 1 - 6 are recognized, with Grade 1 being the mildest, and Grade 6 the most severe. The grading system is based largely on how loud the murmur is, but other factors are also considered, such as the area over which the murmur is audible.
Grade 1 Heart Murmur in Cats: Essentially inaudible.
Grade 2 Heart Murmur in Cats: Heard readily but softly. Always focal.
Grade 3 Heart Murmur in Cats: Heard readily, moderate intensity. Regional.
Grade 4 Heart Murmur in Cats: Heard readily, loud and usually radiates widely.
Grade 5 Heart Murmur in Cats: Heard readily, loud and with a precordial thrill.
Grade 6 Heart Murmur in Cats: Heard readily, loud and with a precordial thrill. Can be heard with the stethoscope lifted 1cm off the thorax.
The grade of the heart murmur does not necessarily relate to the degree of severity of the underlying heart problem. Some severe heart conditions may not be associated with any heart murmur at all, and some quite loud murmurs may occur with relatively small defects.
Heart Murmurs in Cats: Symptoms
The most common symptoms that are observed with a cat that has a clinically significant heart murmur are poor appetite, weight loss (or stunted growth in a kitten), breathing problems, pale gums, lethargy, or weakness.
The Potential Causes of Heart Murmurs in Cats
The presence of a murmur generally implies an underlying heart condition, murmurs can sometimes have other causes.
In young kittens, ‘innocent’ heart murmurs may be heard as an incidental finding. These are usually no longer present when the kitten is older. Anemia is another cause of heart murmurs in cats, but the cats often show other signs of lethargy and anorexia as well.
Occasionally cats are reported to have incidental murmurs as adults, which is when the blood flow within the large vessels exiting the heart may occasionally be heard as a murmur.
Heart Murmurs in Cats: Treatment Options
When a heart murmur is first discovered in a cat, an investigation will be performed to find out the underlying issue. This may involve further tests such as an X-ray of the heart or a cardiac ultrasound examination.
If however the cat is showing no other signs of a problem and is exercising normally, then your vet may suggest you come back for a second examination in a few months to reassess the heart murmur and see if it has changed.
Sometimes if the cat is well and the heart murmur is unchanged, a periodic examination will be recommended.
The only way to determine if there is any disease within the heart itself that may be causing the murmur is to perform a detailed ultrasound examination of the heart. This is completely painless and is normally performed in a fully conscious cat.
Note: The advice provided in this post is intended for informational purposes and does not constitute medical advice regarding pets. For an accurate diagnosis of your pet's condition, please make an appointment with your vet.