Heart disease affects dogs of all breeds and ages—but with early detection, many pups can still live long, happy lives. In this guide, we’ll break down the most common types of canine heart disease, from congenital conditions to acquired illnesses like DCM and MVD. You’ll learn:
- Key symptoms (like coughing and fatigue)
- Which breeds are highest risk
- Proven prevention strategies
- How to support a dog with heart disease
Arm yourself with knowledge to spot warning signs early and partner with your vet for the best care. Because when it comes to your dog’s heart, every beat matters.
Understanding Heart Disease in Dogs
Heart disease in dogs encompasses various conditions that impair heart function or structure. It can be congenital (present at birth) or acquired (developing over time). While congenital issues are often genetic, acquired heart disease may stem from infections, nutritional deficiencies, or age-related changes.
Your dog’s heart is vital—it pumps oxygen-rich blood to nourish organs and tissues. When heart disease strikes, blood flow is disrupted, potentially damaging other organs. Early detection is key to protecting your pet’s health.
Congenital vs. Acquired Heart Disease in Dogs
Congenital Heart Disease (Present at Birth)
Congenital heart defects involve structural abnormalities in the heart’s walls, valves, or vessels. While rare (only ~1% of canine heart cases), certain breeds are more prone, including:
- Small breeds: Bichon Frise, Poodle, Pomeranian, Maltese, Yorkie
- Others: Keeshond, Corgi
Common congenital conditions:
- Patent Ductus Arteriosus (PDA)
- Subaortic Stenosis
- Ventricular Septal Defect (VSD)
Acquired Heart Disease (Develops Over Time)
More common in older dogs, acquired conditions progress slowly due to:
- Aging
- Infections
- Underlying health issues
Key Takeaway: Some congenital defects can later contribute to acquired disease. Knowing the difference helps guide treatment and long-term care for your dog.
The Anatomy of a Dog’s Heart
A dog’s heart works like a human heart. It is a strong organ divided into four parts: two upper sections called atria and two lower sections called ventricles. The heart muscle, known as the myocardium, squeezes to pump blood.
The heart valves act like gatekeepers. They make sure that blood only flows in one direction. These valves open and close with each heartbeat. This stops blood from flowing backward, which is very important for good blood flow in the body.
When the heart muscle squeezes, it pushes blood from the ventricles into the arteries. The arteries carry oxygen-rich blood to the body’s tissues. At the same time, the heart gets blood that lacks oxygen from the body and sends it to the lungs to gather oxygen.
Common Types of Heart Disease in Dogs
Heart disease in dogs comes in many forms, each with unique symptoms and risks. Recognizing the warning signs early can help pet owners seek timely veterinary care, improving their dog’s quality of life. The three most common types are:
1. Canine Dilated Cardiomyopathy (DCM)
DCM weakens and enlarges the heart muscle, reducing its ability to pump blood efficiently.
At-Risk Breeds:
- Doberman Pinschers
- Great Danes
- Boxers
- Cocker Spaniels
Possible Causes:
- Taurine deficiency (common in Cocker Spaniels)
- Carnitine deficiency (linked to Boxer DCM)
Symptoms:
- Fatigue & weakness
- Swollen abdomen (fluid buildup)
- Exercise intolerance
Treatment:
- Medications (ACE inhibitors, diuretics)
- Dietary adjustments (taurine/carnitine supplements)
- Regular vet monitoring
2. Mitral Valve Disease (MVD)
MVD is the most common canine heart disease, especially in small senior dogs. It occurs when the mitral valve degenerates, causing blood leakage (regurgitation).
High-Risk Breeds:
- Cavalier King Charles Spaniels
- Dachshunds
- Chihuahuas
Symptoms:
- Chronic coughing (especially at night)
- Labored breathing
- Lethargy & reduced stamina
Treatment:
- Medications to improve heart function
- Regular cardiac checkups
- Weight & exercise management
3. Canine Heartworm Disease
A potentially fatal condition caused by foot-long parasitic worms (transmitted by mosquitoes) that clog the heart and lungs.
Prevention is Key:
- Monthly preventatives (chewables/topicals)
- Annual heartworm testing
Symptoms (Often Late-Stage):
- Persistent cough
- Difficulty breathing
- Weight loss & lethargy
- Swollen belly (from fluid)
If Untreated: Can lead to heart failure and death.
Recognizing the Signs of Heart Disease in Dogs
Early detection of heart disease can save your dog’s life. Since dogs often hide symptoms, watch closely for changes in breathing, energy levels, or unusual coughing. If your dog shows persistent symptoms, seek veterinary care immediately—early intervention greatly improves outcomes.
Early Warning Signs
- Chronic Coughing
- Dry, hacking cough (often worse at night or after exercise)
- Differentiate from kennel cough (which causes a honking sound)
- Lethargy & Exercise Intolerance
- Sudden disinterest in walks/play
- May accompany weight loss or reduced appetite
- Difficulty Breathing
- Rapid, shallow breaths (even at rest)
- Could indicate fluid in lungs (a sign of worsening heart disease)
Emergency Symptoms: Seek Vet Care NOW
These signs may indicate congestive heart failure or another life-threatening condition:
Blue-tinged gums/tongue (cyanosis)
→ Signals severe oxygen deprivation
Weakness or collapsing/fainting
→ May indicate dangerously low blood flow
Swollen abdomen (fluid buildup)
→ Often linked to right-sided heart failure
Key Takeaways for Pet Owners
✅ Don’t wait—subtle symptoms (like tiredness or mild cough) can escalate quickly.
✅ Monitor high-risk breeds (e.g., Cavaliers, Dobermans) more closely.
✅ Record symptoms (videos help vets diagnose).
Pro Tip: Ask your vet about annual heart screenings for senior dogs or predisposed breeds.
Diagnosis and Treatment Options
Diagnosing heart disease in dogs usually means doing a deep physical check-up. The vet will listen to your dog’s heart and lungs. They might also use tests, like X-rays, EKGs, and echocardiograms. Getting the right diagnosis is important. It helps create a good treatment plan for your dog’s needs.
The treatment options depend on what type and how bad the heart disease is. Vets often prescribe medications. Some of these include diuretics, which help reduce fluid buildup, and ACE inhibitors, which help with blood flow. Doctors may also suggest changes to your dog’s lifestyle. This can include adjusting their diet, managing their weight, and limiting exercise.
Diagnostic Tests for Heart Disease in Dogs
Veterinarians utilize several diagnostic tests to accurately diagnose heart disease in dogs and determine the best course of treatment. These tests provide valuable insights into the heart’s structure, function, and overall health.
| Test | Description |
| Echocardiogram | An ultrasound of the heart that allows visualization of its structure, blood flow, and valve function. |
| Electrocardiogram | Measures the heart’s electrical activity, detecting irregularities in heart rhythm and rhythm disturbances. |
| Radiographs | X-ray imaging of the chest to assess the size and shape of the heart and identify any fluid buildup in the lungs. |
| Blood Pressure | Measures the force of blood against the artery walls, helping to diagnose hypertension, a common comorbidity in heart disease |
These diagnostic tests, along with a comprehensive physical exam, provide your veterinarian with a comprehensive understanding of your dog’s heart health and guide them in creating a tailored treatment plan.
Managing Heart Disease: Medications and Therapies
Managing heart disease in dogs needs a well-rounded approach. This includes medicine, changes in diet, and lifestyle adjustments. Your veterinarian will work with you to make a treatment plan that fits your dog’s unique needs. This plan will focus on the type and severity of their heart condition.
Some common medications for heart disease in dogs are:
- ACE inhibitors: Drugs like enalapril or benazepril help to relax blood vessels. This reduces stress on the heart and improves blood flow.
- Diuretics: Medicines such as furosemide help to remove extra fluid from the body. This can reduce congestion and make breathing easier for dogs with heart failure.
- Pimobendan (Vetmedin®) – The gold standard for Dilated Cardiomyopathy (DCM) and mitral valve disease (MMVD). It improves heart contractions and delays heart failure progression.
- Beta-Blockers (e.g., Atenolol, Carvedilol) These medications slow the heart rate and reduce its workload by blocking adrenaline effects. They are often used for conditions like mitral valve disease or arrhythmias (irregular heartbeats).
- Vasodilators (e.g., Hydralazine, Amlodipine) These drugs widen blood vessels to lower blood pressure and reduce strain on the heart. They are sometimes used in cases of congestive heart failure (CHF) or hypertension-related heart disease.
Which Are Used Most Often?
- Pimobendan + Furosemide + ACE Inhibitors = Core Trio for most heart failure cases (especially DCM and MMVD).
- Beta-blockers & vasodilators are secondary, used for specific conditions like arrhythmias or uncontrolled hypertension.
Living with Heart Disease: Caring for Your Dog
A heart disease diagnosis can feel overwhelming, but with proper management, your dog can still enjoy a happy, comfortable life. Here’s how to support them:
1. Diet & Nutrition
- Low-sodium food: Reduces fluid retention (ask your vet for recommendations).
- Heart-healthy supplements: Omega-3s and taurine may support cardiac function.
- Weight management: Excess weight strains the heart—work with your vet on a safe weight-loss plan if needed.
2. Safe Exercise Guidelines
- Short, gentle walks: Avoid overexertion.
- Low-impact activities: Swimming or slow play sessions.
- Watch for fatigue: Stop immediately if your dog pants excessively or lies down.
3. Home Monitoring Tips
- Track resting heart rate:
- Place fingers on the inner thigh (femoral artery).
- Count beats for 15 seconds, multiply by 4.
*Normal range: 60–140 bpm (varies by breed/size).*
- Watch for worsening symptoms:
- Increased coughing
- Labored breathing at rest
- Loss of appetite
4. Veterinary Care Essentials
- Regular checkups: Helps adjust medications (e.g., diuretics, ACE inhibitors).
- Diagnostic tests: X-rays, echocardiograms, or blood work to track progression.
- Emergency plan: Know your vet’s after-hours protocol.
5. Emotional Support
- Quality time: Gentle affection keeps spirits high.
- Maintain routines: Stability reduces stress.
- Comfort measures: Orthopedic beds, easy-access food/water.
FAQ’s-Types of Heart Disease in Dogs
What is the life expectancy of a dog with heart disease?
The prognosis varies by type and stage:
Early-stage MVD: 1-3+ years with treatment
Controlled DCM: 6 months-2 years
Heartworm disease: Excellent if caught early (but fatal if untreated)
Key factors: Breed, age, and how quickly treatment begins.
Can heart disease in dogs be prevented?
Not all types of heart disease in dogs can be prevented, but there are steps you can take to lower the risk. Keeping a healthy weight, giving a balanced diet, ensuring regular exercise, and using heartworm prevention medicine can help keep their heart healthy. These actions may reduce the chance of some types of heart disease but do not include congenital abnormalities.
How does heart disease affect a dog’s behavior?
Watch for:
Lethargy (sleeping more, refusing walks)
Irritability (due to discomfort)
Restlessness at night (common with fluid buildup)
Reduced social interaction
What Are the First Signs of Heart Problems?
Top 3 Early Red Flags:
Cough (especially after lying down)
Panting excessively without exercise
Sudden weight loss/gain
Which Dog Breeds Are Highest Risk?
Small breeds: Cavalier King Charles Spaniels, Dachshunds
Large breeds: Dobermans, Great Danes, Boxers
All dogs: Heartworm can affect any breed
Tip: Ask your vet about breed-specific screening if you have an at-risk dog.
Final Thoughts: Protecting Your Dog’s Heart Health
As a pet owner, understanding canine heart disease is one of the most powerful ways to extend and improve your dog’s life. Key takeaways to remember:
- Knowledge Saves Lives
- Recognize the difference between congenital (present at birth) and acquired (developed over time) conditions
- Stay alert for early warning signs like coughing, fatigue, or breathing changes
- Proactive Care Makes All The Difference
- Never ignore symptoms – early veterinary intervention can slow progression
- Maintain regular checkups, even if your dog seems healthy
- Daily Management Matters
- Follow prescribed medication schedules strictly
- Implement vet-approved nutrition and safe exercise routines
- Learn to monitor vital signs at home (resting heart rate, breathing rate)
While a heart disease diagnosis can be frightening, many dogs live full, happy lives with proper management. Your awareness and quick action are your pet’s greatest advantages.
