Heart disease is not exclusive to humans. Dogs and cats can also develop various heart conditions. In humans, heart disease is most often correlated with a high cholesterol level and an unhealthy lifestyle, which can lead to coronary artery blockages. However, your dog or cat may have been born with heart disease (i.e., congenital) or their condition may have developed later in life. Our Neighborhood Veterinary Centers of Nederland team shares information about pets’ heart disease risk factors, types, and management.

Heart disease versus heart failure in pets

Heart disease and heart failure are two separate conditions, and you must understand the difference to comprehend pet heart disease. Heart diseases affect cardiac function, usually because the organ’s muscle or valves undergo structural changes. Heart disease often progresses with time and may lead to heart failure (i.e., the heart’s inability to meet the body’s blood-pumping demands). 

The time during which heart disease progresses to heart failure depends on the disease process and severity. For some pets, the progression can take several years or a lifetime. However, for other affected pets, the progression takes only a few months. Once heart failure develops, a pet typically lives between 6 to 18 months. Many heart diseases are asymptomatic until heart failure begins, when a pet may exhibit exercise intolerance, weight loss, general fatigue, coughing, fluid buildup in their chest or abdomen, or collapse. 

Cardiomyopathies in pets

Cardiomyopathies are the most common heart problem in cats and the second most common problem in dogs. Nearly all cats with heart disease have hypertrophic cardiomyopathy (HCM), a condition that causes the heart muscle to thicken. Cats with HCM are likely genetically predisposed to the disease, although hyperthyroidism may be the cause. HCM cats have a high risk for developing blood clots that can cause sudden death, stroke, or paralysis. 

Around 25% of dogs with heart disease, mostly large breeds such as Doberman pinschers and golden retrievers, have dilated cardiomyopathy (DCM). Rather than experiencing heart muscle thickening as do cats, DCM dogs develop muscle thinning, and the heart chambers enlarge or dilate. The thin muscle is weak and cannot pump effectively, leading most affected dogs to develop heart failure. Boxers develop a special cardiomyopathy type that leads to heart arrhythmias and collapse. 

Degenerative valve disease in pets

Degenerative mitral valve disease is the most common heart disease in dogs. Small breeds are most often affected, but large breeds are also at risk. The thickened, abnormal valve causes blood to leak backward against the normal flow. Pets diagnosed with this disease early in life are likely to develop heart failure. This is especially common in Cavalier King Charles spaniels and dachshunds. Older pets diagnosed with this condition often outlive their disease because it tends to progress extremely slowly.

Congenital heart diseases in pets

Congenital heart diseases mostly occur in dogs. Only a small percentage of cats are born with heart problems. In dogs, common congenital conditions include abnormally narrowed blood vessels or valves, and open connections between vessels or heart chambers. Congenital heart conditions’ severity vary greatly. Some pets with minor conditions live normal lives, while others may need surgery to live normally. However, pets with severe congenital heart conditions may not live past middle age.

Heartworm disease in pets

Heartworm infections can lead to heart disease in dogs and cats because the worms physically damage the heart, lungs, and blood vessels. In severe cases, pets may need the heartworms surgically removed to prevent sudden death from a vessel blockage. You can easily prevent your pet from developing heartworm disease by ensuring they receive monthly preventive medication. In addition, your veterinarian can detect the disease in its early stages by performing a routine blood test during your furry pal’s annual wellness examination.

Heart disease diagnosis in pets

Our Neighborhood Veterinary Centers at Nederland team may first suspect your four-legged friend has a heart problem when we hear a heart murmur (i.e., an abnormal, whooshing heart sound), an abnormal heart rhythm or rate, or muffled, crackling sounds that could indicate fluid around the heart or lungs. We will then assess your pet’s blood pressure. To determine the nature of your pet’s heart disease, we may recommend a chest X-ray or a heart ultrasound (i.e., electrocardiogram [ECG or EKG]). A heart ultrasound is the most important cardiac diagnostic tool, which is typically performed and interpreted by a veterinary cardiologist. Once your pet is diagnosed with heart disease, they will likely need regular follow-up X-rays, ultrasounds, and cardiologist visits to monitor progression.

Heart disease management and outlook for pets

Most heart diseases can be well-managed for many months or years through medical therapy. Cardiac medications often include diuretics to decrease fluid buildup, and drugs that modify heart rate, heart muscle strength, or blood pressure. A diet rich in omega-3 fatty acids, taurine, and antioxidants may also help manage some pets’ heart disease. Unfortunately, heart disease is almost always progressive, and some affected pets die from their condition while others live a normal lifespan.

Pets’ most common heart disease risk factors are uncontrollable—breed and age. The most effective heart disease prevention strategy is to feed your pet a complete, balanced, and high-quality diet throughout their life. By scheduling your pet’s annual wellness and preventive care visits with our Neighborhood Veterinary Centers of Nederland team, you help ensure your four-legged friend’s heart disease is diagnosed in the earliest stages, improving your furry pal’s long-term prognosis.