Cardiac Issues in Dogs

Overview

Many dog owners are surprised to hear that their dog can develop heart disease. It is estimated that as many as 7.8 million dogs in the United States have heart disease, equating to approximately 10 percent of the population.

Despite these surprisingly high rates, many remain unaware that their dog’s heart health is at risk. Cardiac issues in dogs can be caused by numerous conditions and variables, ranging from valvular disease to heartworm disease. Preventative measures are imperative.

What Dog Breeds Are Most At Risk for Cardiac Issues?

There are two forms of inherited heart disease that veterinarians see most often, including degenerative mitral valve disease (DMVD) and dilated cardiomyopathy (DCM). DMVD typically impacts small breeds more frequently, while DCM tends to affect larger breeds.

The incidence of DMVD occurs more frequently in Cavalier King Charles Spaniels than any other breed. Unfortunately, by the age of five, 50 percent will develop a heart murmur, and 100 percent will by the age of 10.

Other breeds commonly impacted by DMVD include:

Dachshunds – DMVD usually develops between 8 and 10 years of age. A leaky valve is common in this breed.
Miniature and toy poodles – Often occurring in middle age, with an even higher incidence among the elderly.

In comparison, DCM tends to affect Doberman Pinschers, with a higher incidence among males. This disease can cause life-threatening arrhythmias.

Other heart conditions that impact specific breeds include:

Sick sinus syndrome (SSS) – Female Miniature Schnauzers are most prone to SSS, which causes the dog’s natural pacemaker to not work properly. Cocker Spaniels and West Highland White Terriers also face an increased risk.
Aortic stenosis – Aortic stenosis is the most common congenital heart disease seen in Golden Retrievers. Other breeds commonly affected include Newfoundland dogs, German Shepherds, Rottweilers, Great Danes, and Samoyeds.
Right ventricular cardiomyopathy (ARVC) – Boxers are highly susceptible to this genetic heart condition. Although isolated cases have been reported in other breeds, it is rare for ARVC to develop in breeds other than boxers.

What Are the Signs of Cardiac Issues in Dogs?

The clinical signs of cardiac issues and heart disease will depend on the type and severity of the disease. Most often, early heart conditions are asymptomatic. This means that there may be no symptoms at all.

Unfortunately, symptoms do not typically develop until a dog’s heart condition progresses to congestive heart failure. At this point, a dog’s heart can not likely meet the demands of the dog’s body. At this point, owners may notice:

Increased fatigue
Reduced motivation to exercise
Breathing difficulties
Loss of appetite and weight loss
Sleep issues
Frequent coughing
Fainting or collapsing
Changes in behavior, including isolation

Since signs do not often show until damage has occurred, it is recommended that your veterinarian screen for cardiac issues each year – especially among high-risk breeds.

Prognosis of Cardiac Issues in Dogs

Once again, depending on the disease and severity, as well as various environmental variables, the prognosis of a dog with cardiac issues will differ.

When dog owners intervene, dogs with advanced heart failure can have fairly long survival times. In this 2018 study, 44 dogs with DMVD were observed. The data was collected when the dogs were diagnosed with Stage C heart failure and advanced heart failure, followed by their date of death.

Once diagnosed, 70 percent of the dogs received medication adjustments. After the diagnosis of advanced heart failure, the average survival time was 281 days. Those who received a daily furosemide dose of >6.70 mg/kg lived significantly longer (an average of 402 days versus 129 days).

Treating Cardiac Issues in Dogs – The Sooner Treatment Begins, the Better

Since each case is unique, it’s important for owners to work with their veterinarian to develop the best course of action.

Depending on the dog’s symptoms, a veterinarian may run a number of tests, including:

A blood and urine test
Heartworm antigen test
Holter monitor (which will capture a dog’s heart rate over the course of 24-48 hours)
Chest x-ray or ultrasound

Once a more formal diagnosis is made, treatment options may include one or more of the following:

Medications that specifically address irregular heartbeats and/or poor heart function, or medications that address bacterial infections/heartworm if applicable, supplements may also be recommended
Medications that will reduce fluid buildup
Surgery to repair a torn valve (a pacemaker may also be required)
A prescription diet
A strict exercise routine to help manage a dog’s weight without playing stress on their heart

Regular visits will be recommended to ensure that the current treatment plan is ideal. With the right treatment plan, care, and monitoring, dogs with cardiac issues can live a long, comfortable life.

Cost to Treat: $1,000 to $20,000

The cost range seems extreme but based on the severity and treatment needed veterinary costs for cardiac issues in dogs can range from simple medications to open heart surgery.

Protect Your Dog to Prevent Cardiac Issues

Although diet and exercise are imperative to prevent obesity, diabetes, and other chronic conditions, the majority of cardiac issues cannot be prevented.

Although you can lower your dog’s risk, if they develop a specific heart condition, professional clinical assistance will likely be required.