Heart failure, often brought on by valvular disease, is one of the most common causes of death amongst small breeds like the Chihuahua, Maltese, and others as they approach their twilight years. Here’s what you need to know about this disease and what you can do if you receive a diagnosis for your dog.
What Is Valvular Disease?
First things first. Valvular disease is a complicated condition, with different stages and levels. The stages range from very mild to very severe. Only a veterinarian can make a diagnosis, and, once it is made, there are treatment strategies that are tailored to the individual dog’s needs. Small breeds are especially prone to developing valvular disease.
“Small dogs get chronic degeneration of their heart valves, particularly two valves,” says Dr. Philip Fox, a cardiologist at Animal Medical Center in New York City. “The mitral and tricuspid valves are most commonly affected. By the time some small dogs are 8 or 10 years old, you have some degree of that, although most of them don’t go on to heart failure.”
When the valves weaken, they no longer close properly. When this happens, blood leaks around the valves and causes the heart to strain. “It’s undoubtedly genetic, but no one knows what the genetics of that are,” says Dr. Fox.
Symptoms of Valvular Disease
Dr. Fox explains that many dogs have no symptoms because, in most cases, the degeneration doesn’t result in heart failure. “Otherwise, dogs would be gone in three generations,” he says. “They’ve been around since before the Egyptians. So a small percentage are affected.”
But if your dog does have valvular disease, some signs and symptoms can include:
- Weight loss
- Becoming weak or tired
- Losing the ability to exercise
- Fainting with excitement or during exercise
In advanced cases, the lungs can fill up with water (also called pulmonary edema), or fluid can build up in the dog’s chest or abdominal cavity. Dogs can also experience a heart murmur that starts soft and gets louder as the years go by. This refers to an unusual sound heard when blood flowing through the heart is turbulent or abnormal. Often, there are no symptoms exhibited until the condition becomes advanced.
What Can You Do to Help Your Dog?
Dr. Fox says that small-breed dog owners should take their pets to the veterinarian annually for a checkup. If the veterinarian hears a heart murmur or an irregular heartbeat, don’t panic. There are treatments available.
From there, the vet can run additional tests including an X-ray or echocardiogram (an ultrasound of the heart) to determine the degree of severity of the valvular disease. Dr. Fox adds that pet owners should feel free to seek a second opinion. In some cases, that may mean referral to a specialist.
For some dogs that have advanced valvular disease, but no symptoms, there are medications that the vet may prescribe for your dog. These include pimobendan, angiotensin-converting enzyme (ACE) inhibitors, and spironolactone.
With advancing valvular disease, the body tries to compensate, which provokes physiologic changes in dogs. Some of those are useful, but at times, the body overproduces these physiologic changes, which can become problematic. The medications work in different ways to try to blunt or reduce adverse effects from what we would call excessive or abnormal physiologic changes.
Considering Nutrition and Diet
There are nutrition and dietary considerations, too. But those recommendations are highly specific and should come from a vet. For instance, some vets may recommend a reduced-sodium diet. The Cummings School of Veterinary Medicine of Tufts University provides a list of lower-sodium dog foods for pets with heart issues.
“Nutrition and diet are very important, as it is with all conditions,” says Dr. Fox. “Diet should play a role in a discussion concerning heart health. There is a role in good nutrition, and it has to be coordinated with each individual’s pet circumstances.”
When it comes to exercise, Dr. Fox says, in general, normal activity is okay (whatever “normal” might mean for your dog). But seek advice from your vet first. Above all, Dr. Fox says, don’t panic if your dog is diagnosed with valvular disease. “Find those remedies that put the pet in the best circumstance to prevail,” he suggests.