Canine heart murmurs can warrant discussion, testing

Q: My Havanese, “Comet,” is 8 years old, and my vet told me that she has a Grade 4 heart murmur. What does that mean, and what do I do? R.T., Farragut

A: A heart murmur is an extra sound that can be heard when listening to the heart through a stethoscope. An abnormality in the heart muscle, valve or blood vessels can cause vibrations when the blood moves through. That vibration is the hissing or blowing sound that we call a heart murmur.

A murmur itself does not always mean that there is heart disease present, but if Comet is 8 years old and a murmur has never been heard before, it does warrant further discussion and testing.

The grading scale for murmurs is the way veterinarians characterize murmurs regarding intensity or loudness. The scale is numbered 1-6, ranging from very soft to very loud.

A Grade 4 murmur is a moderately loud murmur. It is important to realize the intensity of the murmur does not always correlate with the degree of heart disease.

Although pets can have innocent murmurs just as people can, it is less likely, given Comet’s age and history. Your veterinarian will count Comet’s heart rate and respiration rate and ask you about any symptoms she might be having.

To gather more information, your veterinarian will likely talk with you about heartworm testing and chest x-rays. Depending on those results, some dogs will need EKG’s, blood pressure measurements and an echocardiogram, an ultrasound of the heart.

Treatment of heart disease in middle-aged and older dogs is often medical, not surgical. There are heart medications available for dogs, and your veterinarian will consult with you regarding what, if anything, Comet may need. Best wishes to you and Comet.

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