Every heartbeat tells a story. In February—Heart Month—we pause to focus on one of the most vital and vulnerable systems in the body: the heart. For dogs and cats, heart health plays a central role in how long they live, how comfortably they age, and how fully they can enjoy life with their families.

At Boundary Bay Veterinary Specialty Hospital (BBVSH), our cardiology team works alongside surgeons, emergency clinicians, and primary care veterinarians to recognize early signs of heart disease, guide thoughtful diagnostics, and support pets and their people through each stage of care. Heart care is not limited to treating disease—it’s about recognizing subtle changes early, intervening thoughtfully, and preserving the moments that matter most between pets and the people who love them.

Heart Disease in Pets: More Common—and More Treatable—Than Many Realize

Heart disease in pets generally falls into two categories:

• Congenital heart disease – conditions present at birth
• Acquired heart disease – conditions that develop over time, often as pets age

While congenital heart defects affect a relatively small percentage of dogs and cats (about 1%), acquired heart disease is far more common, particularly in adult and senior pets. Advances in veterinary cardiology now allow many pets with heart disease to live longer, more comfortable, and more active lives than ever before.

Early diagnosis and appropriate management dramatically improve outcomes across nearly all forms of heart disease in pets. Early changes are often subtle—but they matter.

How the Pet Heart Works—and What Happens When Disease Disrupts It

The heart is a pump. When it works efficiently, oxygen-rich blood reaches every organ. When something interferes—whether it’s a faulty valve, abnormal blood flow, or weakened heart muscle—the body pays the price.

Common cardiac conditions we see include:

• Degenerative valve disease – valves become leaky over time
• Dilated cardiomyopathy (DCM) – the heart muscle weakens and enlarges
• Hypertrophic cardiomyopathy (HCM) – thickened heart muscle, most common in cats
• Congenital defects such as patent ductus arteriosus (PDA) or pulmonic stenosis

Many of these conditions begin silently. A heart murmur, irregular rhythm, or subtle breathing change may be the first—and most important—clue.

At BBVSH, our cardiology team uses advanced diagnostics such as echocardiography (cardiac ultrasound), ECGs, cardiac CT scans, and thoracic imaging to identify disease before irreversible damage occurs.

Recognizing Early Signs of Heart Problems in Pets

Heart disease in dogs and cats often develops gradually, and early changes can be easy to miss. In many cases, the first signs appear as small shifts in behavior or activity rather than obvious illness.

Pet owners may notice:

• Reduced interest in exercise or play
• Fatigue during activities that were previously easy
• Coughing or changes in breathing effort
• Faster breathing at rest
• Weakness or collapse
• Subtle behavior changes, especially in cats, such as hiding or decreased interaction

Cats are particularly skilled at masking illness, which means signs of heart disease may not be obvious until the condition is more advanced. Regular veterinary exams remain one of the most reliable ways to detect early heart changes before they significantly affect daily life.

Diagnosing Heart Disease in Dogs and Cats: What Testing Can Reveal

When heart disease is suspected, diagnosis begins with a thorough physical examination. Findings such as a heart murmur or irregular rhythm often prompt further evaluation by a cardiology team.

Diagnostic testing may include:

• Chest X-rays to assess heart size and lung changes
• Electrocardiography (ECG) to evaluate heart rhythm and electrical activity
• Echocardiography (cardiac ultrasound) to visualize heart structure, valve function, and blood flow
• Cardiac CT imaging in select cases to provide detailed views of the heart and major blood vessels

Together, these tools help define the type and severity of heart disease and guide care plans tailored to each patient.

When Heart Surgery or Intervention Is Part of a Pet’s Care Plan

Not all heart disease requires surgery—but when it does, timing and expertise are critical.

• Surgical ligation of patent ductus arteriosus (PDA)
• Balloon valvuloplasty for pulmonic stenosis
• Advanced cardiovascular surgical interventions

BBVSH’s board-certified surgeons and cardiology team work together to determine if surgery is indicated, when it should occur, and which approach offers the safest and most effective outcome.

Why Early Attention to Pet Heart Health Changes Outcomes

A puppy with a faint murmur, a cat breathing slightly faster at rest, or a dog slowing down on walks may be showing the earliest signs of heart disease. Early identification allows for less invasive treatment, better medication response, improved long-term prognosis, and reduced risk of emergency heart failure.

Heart disease doesn’t always announce itself loudly. Sometimes it whispers.

Heart care is an ongoing process. At BBVSH, our cardiology team, board-certified surgeons, emergency clinicians, collaborate with primary care veterinarians to provide continuity of care from diagnosis through long-term management.

Frequently Asked Questions About Heart Disease in Pets

What is the most common type of heart disease in dogs and cats?

Acquired heart disease is most common. Dogs frequently develop degenerative valve disease, while cats are more often affected by hypertrophic cardiomyopathy (HCM). Congenital heart disease is less common but can be severe if untreated.

Can pets live a normal life with heart disease?

Yes. With early diagnosis and appropriate management, many pets live long, comfortable, and active lives.

What is a heart murmur, and does it always mean heart disease?

A heart murmur is an abnormal sound caused by turbulent blood flow. Not all murmurs indicate serious disease, but they often warrant further evaluation.

What signs of heart disease should pet owners watch for?

Signs may include reduced exercise tolerance, coughing, faster or labored breathing, weakness, or fainting. Cats may show subtle changes such as hiding or increased resting respiratory rate.

How is heart disease diagnosed in pets?

Diagnosis involves a physical exam and diagnostics such as chest X-rays, ECGs, and echocardiography to assess heart structure and function.

When is heart surgery recommended for pets?

Surgery or interventional procedures may be recommended for certain congenital or structural conditions, depending on disease severity and timing.

Why is early detection of heart disease so important?

Early detection allows intervention before irreversible damage occurs, improving quality of life and long-term outcomes.

Should puppies and kittens be screened for heart disease?

Yes. Routine veterinary exams early in life are critical, as congenital heart defects may not cause visible symptoms at first.

Why is February recognized as Heart Month for pets?

Heart Month raises awareness about cardiovascular health, emphasizes early detection, and encourages proactive care to support long, healthy lives.