Heart Valve Malformation in Dogs (Atrioventricular Valve Dysplasia): Causes, Symptoms, Diagnosis, Treatment & Long-Term Care

Introduction: Understanding Heart Valve Malformation in Dogs

Heart Valve Malformation in Dogs is a congenital heart condition that affects how efficiently blood moves through the heart. One of the most significant forms of this disorder is Atrioventricular Valve Dysplasia in Dogs (AVD), a developmental abnormality of the heart’s mitral or tricuspid valves.

Heart Valve Malformation in Dogs

Because this condition is present at birth, many dogs begin life appearing normal. However, as they grow, the malformed valves may place increasing strain on the heart, eventually leading to dog heart valve disease and, in severe cases, congestive heart failure. For dog owners, understanding this condition early is critical to protecting long-term quality of life.

With proper veterinary care and proactive cardiovascular support—such as HeartRX™ from RX Sciences®—many dogs with heart valve malformations can live comfortable, fulfilling lives.

Read more: What Are the Last Stages of Congestive Heart Failure in Dogs?

What Is Heart Valve Malformation in Dogs?

Atrioventricular Valve Dysplasia Explained

Atrioventricular Valve Dysplasia occurs when one or both atrioventricular valves fail to form normally during fetal development. These valves function like one-way doors between the heart’s chambers, opening and closing with every heartbeat to keep blood flowing in the correct direction.

When a valve is malformed, it may not seal tightly. This allows blood to leak backward, forcing the heart to work harder to circulate blood throughout the body. Over time, this added workload can cause the heart to enlarge and weaken.

According to PetMD, atrioventricular valve dysplasia is a developmental malformation of the mitral or tricuspid valve and can progress to congestive heart failure when severe.

Mitral vs. Tricuspid Valve Dysplasia

• Mitral valve dysplasia affects the left side of the heart and is the more commonly diagnosed form

• Tricuspid valve dysplasia affects the right side and is often seen in large-breed dogs

• Some dogs may be affected by both

Read more: Congestive Heart Failure in Dogs: A Complete & Hopeful Care Guide

Causes & Risk Factors

Genetic and Developmental Origins

The primary cause of Heart Valve Malformation in Dogs is genetics. The defect develops before birth, meaning it is not caused by diet, exercise, or environment after the puppy is born.

Risk factors include:

• Inherited genetic mutations

• Breed predisposition

• Possible intrauterine developmental influences

Breeds More Commonly Affected

Veterinary research shows higher rates of atrioventricular valve dysplasia in:

• Labrador Retrievers

• Golden Retrievers

• German Shepherds

• Great Danes

• Boxers

• Bulldogs

Because this condition is inherited, affected dogs should not be used for breeding.

Signs & Symptoms of Dog Heart Valve Disease

Early Symptoms

Mild cases may show no outward signs at first. Often, the earliest clue is a heart murmur detected during a routine veterinary exam.

Other early symptoms may include:

• Exercise intolerance

• Fatigue or weakness

• Rapid breathing after activity

• Slower growth in puppies

Progressive and Advanced Symptoms

As valve dysfunction worsens, dogs may develop:

• Persistent coughing, especially at night

• Labored or rapid breathing at rest

• Fluid buildup in the lungs or abdomen

• Fainting episodes

• Weight loss and muscle weakness

Early recognition allows for earlier intervention and supportive care, including proactive cardiovascular supplementation with HeartRX™.

Diagnosis of Atrioventricular Valve Dysplasia

Diagnosing Heart Valve Malformation in Dogs requires a combination of physical exams and diagnostic imaging.

Common diagnostic tools include:

• Auscultation: Listening for heart murmurs

• Chest radiographs (X-rays): Evaluating heart size and fluid accumulation

• Echocardiography: Ultrasound imaging to visualize valve structure and blood flow

• Electrocardiogram (ECG): Detecting abnormal heart rhythms

• Bloodwork: Assessing overall health and organ function

Echocardiography is considered the gold standard for diagnosing Atrioventricular Valve Dysplasia in Dogs.

Treatment & Management of Heart Valve Malformation in Dogs

Is There a Cure?

There is currently no cure for congenital valve malformations. Treatment focuses on managing symptoms, slowing disease progression, and supporting heart function over time.

Veterinary Treatment Options

Management plans may include:

• Diuretics to reduce fluid buildup

• ACE inhibitors to decrease cardiac workload

• Pimobendan to improve heart efficiency

• Exercise moderation

• Heart-friendly, low-sodium diets

Ongoing veterinary monitoring is essential, as medication needs often change as the condition progresses.

The Role of HeartRX™ in Long-Term Heart Support

While medications address clinical symptoms, long-term success also depends on supporting the heart at a cellular and functional level. This is where HeartRX™ plays an important role.

Developed by RX Sciences, HeartRX™ is formulated to support dogs experiencing cardiovascular stress, including those diagnosed with Heart Valve Malformation in Dogs and heart murmurs.

HeartRX™ supports canine cardiovascular health by:

• Supporting healthy heart muscle function

• Promoting efficient circulation and blood flow

• Helping reduce oxidative stress that burdens cardiac tissue

• Supporting long-term heart resilience and vitality

HeartRX™ is designed to complement veterinary treatment plans—not replace them—making it a valuable part of a proactive, lifelong care strategy.

🔗 Learn more about HeartRX™: https://www.rxsciences.co/heartrx

Life With Atrioventricular Valve Dysplasia

Prognosis and Quality of Life

The outlook for dogs with Atrioventricular Valve Dysplasia varies based on:

• Severity of the valve abnormality

• Age at diagnosis

• Response to medical and supportive care

Many dogs live for years with good quality of life when medical management is combined with consistent monitoring and cardiovascular support such as HeartRX™.

Daily Care Tips for Dog Owners

• Schedule regular cardiac evaluations

• Monitor resting breathing rate at home

• Maintain a healthy body weight

• Avoid excessive exertion

• Use supplements consistently as recommended by your veterinarian

Prevention & Genetic Responsibility

Because heart valve malformations are congenital:

• Affected dogs should not be bred

• Breeders should perform cardiac screenings

• Genetic responsibility helps reduce future cases

Frequently Asked Questions (FAQs)

Can dogs live long with heart valve malformation?

Yes. With early diagnosis, proper treatment, and supportive care, many dogs live comfortable, meaningful lives.

Is HeartRX™ safe to use with heart medications?

HeartRX™ is designed to complement veterinary care, but always consult your veterinarian before introducing any supplement.

What breeds are most at risk?

Large breeds such as Labradors, German Shepherds, and Great Danes are more commonly affected.

Does every heart murmur mean heart valve disease?

No, but all murmurs should be evaluated by a veterinarian.

Can supplements cure atrioventricular valve dysplasia?

No. Supplements support heart health but cannot correct congenital valve defects.

When should heart support begin?

Early support—especially after a murmur or diagnosis—is often beneficial.

Conclusion: A Proactive Path Forward

Heart Valve Malformation in Dogs, including Atrioventricular Valve Dysplasia, is a lifelong condition—but it does not have to define a dog’s future. With informed veterinary care, attentive monitoring, and science-backed cardiovascular support like HeartRX™ from RX Sciences, dogs with congenital heart disease can enjoy improved comfort, resilience, and longevity.

If your dog has been diagnosed with a heart murmur or valve disorder, speak with your veterinarian about a comprehensive care plan—and consider how HeartRX™ can support your dog’s heart health for the long journey ahead.