Find out if your dog suffers from this surprisingly common heart condition. You can help make his life easier.

Canine Heart Murmur Study

For each dog, cardiac auscultation (listening to heart sounds with the use of a stethoscope) was performed by at least three different examiners: a board-certified veterinary internist, a veterinary cardiology resident, and a veterinary internal medicine resident. The examiners did not compare findings.

Additional tests included a urinalysis, complete blood count (CBC), and serum chemistry profile, along with an echocardiogram (EKG).

What the Researchers Discovered
Murmurs were noted in 22 of the 95 dogs, or 23 percent.

Of the 22 murmurs, 10 were detected only by the board-certified veterinary internist
In 69 percent of the dogs, all three investigators reported the same findings.
There were no significant differences in sex, age, body weight, or breed between dogs with murmurs and dogs without murmurs
11 of the 22 dogs with murmurs had EKG abnormalities, including mild mitral valve regurgitation (leakage of blood backward through the mitral valve each time the left ventricle contracts), subaortic stenosis, and pulmonary valve stenosis (obstruction of blood flow from the right ventricle to the pulmonary artery)
These results indicate a prevalence of physiological heart murmurs in between 6 and 12 percent (depending on the EKG criteria used) of the 95 dogs in the study, with 27 to 50 percent of the 22 murmurs considered physiological.

The researchers concluded the presence of physiological heart murmurs may extend beyond specific predisposed breeds and growing dogs to a larger population of young, healthy adult dogs.

Unfortunately, Heart Problems in Dogs Are Relatively Common

When a veterinarian listens to a dog's heart, he or she is evaluating heart rate and rhythm, as well as heart sounds. In a healthy heart, there are just two sounds (“lub-dub”), and they can be clearly heard — they aren't muffled or difficult to pick up. The “lub” is as loud as the “dub,” and the rhythm is regular.

The “lub-dub” sound is the result of the heart valves closing as blood flows out of the heart chamber. If a valve doesn't close completely, blood can flow backward into the heart, creating the sound referred to as a murmur.

Symptoms to Watch for and Treatment Options
A few signs to watch for if you suspect or know your pet has a heart problem include:

Coughing
Bluish appearing tongue
Loss of appetite
Fatigue, weakness, loss of stamina, and decreased exercise endurance
Too fast or too slow heart beat; increased respiratory effort, including increased respiratory rate
Cardiologists don't actually treat heart murmurs, however, the underlying cause can sometimes be addressed, depending on a variety of factors including the severity of the murmur, the age and health of your dog, the cost of treatment, and other concerns. If possible, I recommend having your dog seen by a board-certified veterinary cardiologist who can provide you with more information about the severity of your pet's heart condition.

Now that you have enough information on doggy heart murmurs, be sure to take your pup to the vet for a full exam. If he suffers from this condition, you can know what to look out for to make sure it is kept in control.

For more information on heart murmurs, visit Healthy Pets.