Your pet’s happy-go-lucky nature makes it easy to forget that their anatomy is similar to yours, and equally complex. A disease that affects an organ can throw off your pet’s internal balance, or homeostasis. Your pet’s heart is a vital organ that pumps blood through their body, helps maintain blood pressure, and ensures oxygen delivery to cells. If the heart becomes compromised by a disease process, the effects can involve their entire body. Our Bolton Veterinary Hospital team explains five common pet heart diseases, and how to recognize signs in your pet.

#1: Hypertrophic cardiomyopathy in cats

Hypertrophic cardiomyopathy (HCM) is the most common heart disease to affect cats. The name translates to “enlarged heart muscle disease,” because HCM causes the heart wall muscle to thicken internally, which shrinks the left ventricle’s capacity. The heart is not able to pump its normal blood volume, and fails to keep up with the body’s blood and oxygen demands. As blood flow becomes sluggish, clots can also form in the heart, break free, and become lodged in the vessels, most commonly those leading to the cat’s back legs. This is known in layman’s terms as a “saddle thrombus.”   This aortic thromboembolism restricts blood flow to the legs, causing paralysis and pain. Not all cats with HCM will develop blood clots, but HCM is typically the precursor to this deadly complication. Unfortunately, HCM often causes no clinical signs until it becomes severe, or aortic thromboembolism occurs. Your veterinarian will thoroughly evaluate your cat’s heart during their annual wellness exam to check for HCM signs. If there is concern about underlying heart disease, an echocardiogram (i.e., ultrasound of the heart) may be recommended. If HCM is diagnosed, medication to improve heart function can be prescribed.  

#2: Dilated cardiomyopathy in dogs

Dilated cardiomyopathy (DCM), which affects dogs, weakens the heart muscle. Pressure from blood flowing through the heart causes the weakened walls to stretch over time, and enlarges the heart chambers. Overall, the heart becomes round and dilated, and does not pump blood efficiently. Medication can be used to improve heart function, but DCM carries a poor prognosis, and eventually leads to death.

Historically, DCM mainly affected genetically predisposed breeds, such as Doberman pinschers and Great Danes, but a recent surge in non-predisposed breeds has been potentially linked to boutique, exotic, and grain-free dog foods. The FDA is still investigating the situation, and we do not yet fully understand the relationship between these diets and DCM. Until more is known, we recommend avoiding these food types, and sticking with reputable manufacturers whose dog foods have undergone rigorous testing and analysis.

#3: Heart valve disease in pets

Your pet’s heart valves open and close with each heartbeat to keep blood flowing in the right direction. Valvular degeneration (i.e., endocardiosis) can inhibit your pet’s valves from closing completely, which leads to backflow (i.e., regurgitation, or a leaky heart valve). This means that some blood flows backward into the atria instead of flowing out of the heart during each contraction. This interferes with normal blood flow and causes a heart murmur, which your veterinarian can detect during a routine wellness exam. Valvular disease is most common in older, small-breed dogs. If your dog develops valvular disease, medications can help their heart function more efficiently.

#4: Heartworm disease in dogs and cats

Heartworms are parasites that are passed to dogs and cats through a mosquito bite. The microscopic larval worms migrate to the pet’s heart and lungs, where they grow to 12-inch-long adults. Mature worms reproduce in dogs, and the growing worm burden clogs their heart and lungs, leading to death without treatment. Heartworms cannot reproduce in cats, but they cause heartworm-associated respiratory disease (HARD), which causes lung inflammation, and can also lead to death. Treatment is available for dogs who contract heartworm disease, but it is costly, and can cause significant side effects, including death, as the worms die. No cure exists for cats, and treatment focuses on decreasing inflammation associated with the worms until they die naturally, which can take years. Heartworm disease in dogs and cats can easily be prevented with prescription medications we can provide. Speak with our veterinary team about the best preventive for your pet.

#5: Congestive heart failure in pets

Congestive heart failure (CHF) is not a primary disease, but develops secondary to another heart condition. When a heart disease, such as HCM, DCM, or valvular disease, leads to inefficient blood flow through the heart, blood backs up in the vessels located in the chest, abdomen, and lungs that lead to the heart. The engorged vessels leak fluid, which accumulates. Fluid in the chest and lungs leads to breathing problems, and in the abdomen causes abdominal distension. CHF can be managed with medications, but the underlying heart condition must also be diagnosed and treated to prevent additional fluid accumulation. 

Recognizing heart disease signs in your pet

Heart diseases that affect pets typically lead to similar clinical signs, despite their different causes. Monitor your pet for signs such as:

  • Lethargy
  • Decreased appetite
  • Tiring easily during exercise
  • Coughing
  • Increased respiratory rate
  • Difficulty breathing
  • Vomiting
  • Pale or blue-tinged gums
  • Passing out

If you believe your pet may have heart disease, contact our Bolton Veterinary Hospital team immediately to schedule an appointment. While heart disease can progress quickly without treatment, many conditions can be managed to improve your pet’s quality of life and allow them to live longer.