Either congenital or acquired later in life, this is a condition you need to be proactive about for the care and comfort of your pet.
A team of researchers in France examined 95 healthy, young adult dogs for signs of physiological heart murmurs; almost a quarter (23 percent) of the dogs had a murmur.
The researchers concluded heart murmurs may extend beyond specific predisposed breeds and growing dogs to a larger population of young, healthy adult dogs.
Dogs discovered to have cardiac arrhythmias or any signs of disease were excluded. Indirect blood pressure measurements were performed to arrive at an average for each dog.
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. All the murmurs were systolic, were primarily over the left heart base, and ranged between Grade I and Grade III. Additional findings:
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
A heart murmur can be caused by abnormal blood flow within the heart that typically involves one or more heart valves. Murmurs can also be the result when the left and right sides of the heart don't communicate efficiently. A murmur can be congenital (present at birth), or it can develop as the result of disease or the aging process.
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.
Stenosis of the aortic or pulmonary valves means the valves have narrowed, causing the heart to work harder to pump blood through the smaller openings. Patent ductus arteriosus (PDA) is a condition in which the ductus arteriosus blood vessel fails to close normally, interrupting the normal blood flow between the aorta and pulmonary arteries that carry blood from the heart.
Heart valve lesions cause murmurs. Congenital (from birth) lesions are much more common in young dogs, while acquired lesions are more often seen in adult dogs.
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:
- 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
Tips to Proactively Protect Your Dog's Heart Health
Ask your veterinarian for the proBNP blood test. This test can give you peace of mind that your dog has no early signs of heart disease. It's a simple blood test with a fast turn-around time that can provide the information you need to proactively manage your dog's heart health.
Help your dog maintain a good body weight through regular aerobic exercise.
Feed a high quality, balanced, and species-appropriate diet that meets your pet's nutritional requirements for optimal protein (and amino acid) levels, healthy fat, EFA's, and coenzyme Q10, as well as critical micronutrients such as vitamins D and E, calcium, and magnesium, which are often deficient in homemade, unbalanced diets.
Take excellent care of your dog's dental health (bacteria from dirty mouths have been linked to heart valve infections in dogs)
Article by Dr. Becker
Images submitted by PNM