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Heart Failure in Dogs

Author: Dr. med. vet. Gisa Löwe | Last modified: 06.02.2026

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Heart failure in dogs is a serious condition in which the heart is unable to pump enough blood to meet the body’s needs. This can lead to a variety of health problems that can significantly impair the affected dog’s quality of life.

Can Occur with the Following Diseases:

Rhabdomyosarcoma of the Muscle (Soft Tissue Cancer of the Muscle)

Basics and possible causes

A dog’s heart consists of four chambers and is responsible for pumping oxygen-rich blood throughout the body. Heart failure occurs when this function is impaired. There are two main types of heart failure in dogs: left-sided and right-sided heart failureRight-sided heart failure is a condition in which the right side of the heart is unable to effectively pump blood to the lungs. In dogs and cats, this can lead to fluid accumulation in the body, especially in the abdominal cavity, and reduced oxygen supply.. Left-sided heart failure is more common and occurs when the left side of the heart does not work properly, while right-sided heart failureRight-sided heart failure is a condition in which the right side of the heart is unable to effectively pump blood to the lungs. In dogs and cats, this can lead to fluid accumulation in the body, especially in the abdominal cavity, and reduced oxygen supply. affects the right side of the heart.

One of the most common causes of heart failure in dogs is mitral valve insufficiencyInsufficiency refers to the inadequate function or performance of an organ or system. This can include, for example, heart failure, kidney failure, or venous insufficiency., a condition in which the heart’s mitral valve is leaky, and blood flows back into the left atriumThe atrium (plural: atria) is one of the two upper chambers in the heart that receive blood from the body (right atrium) or from the lungs (left atrium).. This leads to an overload of the heart. Another cause can be dilated cardiomyopathy, in which the heart muscle enlarges and weakens, impairing the heart’s pumping ability.

In addition, congenitalCongenital means "present from birth" and refers to characteristics or conditions that are already present at birth. This can include genetic disorders, developmental anomalies, or infections transmitted by the mother. heart defects, myocarditis, cardiac arrhythmiaAn arrhythmia is a heart rhythm disorder in which the heart beats irregularly, either too fast (tachycardia), too slow (bradycardia), or with an irregular pattern. Arrhythmias can be harmless or a sign of serious heart problems., or other systemic diseases such as hypothyroidism can contribute to the development of heart failure. Factors such as age, breed, and genetic predispositionA predisposition is an innate inclination or susceptibility of an organism to certain diseases or conditions. In dogs and cats, there may be a genetic predisposition to certain conditions such as hip dysplasia or certain heart diseases. also play a role. Certain dog breeds, such as Cavalier King Charles Spaniels, Dobermans, and Boxers, have a higher risk of heart disease.

Typical accompanying symptoms

Cough: A common sign that often occurs at rest or at night. It can be caused by fluid accumulation in the lungs.
RespiratoryRespiratory refers to breathing or the process of breathing. Respiratory diseases affect the respiratory tract and can impair the ability to breathe effectively. distress: Dogs with heart failure may have difficulty breathing, which can manifest as rapid or labored breathing.
Lethargy: Affected dogs often show fatigue and reduced urge to move because their heart cannot transport enough oxygen to the muscles.
Weight loss: Possible weight loss can be caused by a reduced food intake due to lethargy or respiratoryRespiratory refers to breathing or the process of breathing. Respiratory diseases affect the respiratory tract and can impair the ability to breathe effectively. distress.
Water retention: Swelling in the abdomenThe abdomen, also known as the abdominal cavity, is the part of the body located between the rib cage and the pelvis. It houses several important organs, including the stomach, liver, kidneys, intestines, and spleen. or limbs may indicate fluid accumulation caused by an inadequately working heart.
Fainting spells: In severe cases, sudden fainting spells can occur if the heart does not pump enough blood to the brain.
Pale or bluish gums: This may be an indicationIndication refers to a valid reason or rationale for using a specific treatment, medication, or medical procedure. It is based on the diagnosis and the patient's clinical condition. of an insufficient oxygen supply to the body.

When to visit the vet?

It is important to seek veterinary attention immediately if a dog shows symptoms of heart failure. In particular, shortness of breath, fainting spells, or a sudden deterioration in general condition require immediate veterinary assistance. Early diagnosis and treatment can significantly improve quality of life and prevent serious complications.

Even if the symptoms appear mild, a veterinarian should be consulted to make an accurate diagnosisA diagnosis is the identification of a disease or condition by its symptoms and/or results from diagnostic tests. It is the first step in the management and treatment of patients. and develop a treatment plan. Regular veterinary check-ups are especially important for dogs prone to heart disease.

Symptom recognition for animal owners and veterinary diagnostic procedures

It is important for pet owners to watch for signs of heart failure and describe them in detail to the veterinarian. Changes in the dog’s behavior, breathing, or energy level can provide important clues. The veterinarian will likely perform a complete clinical examination, which includes listening to the heart with a stethoscopeA stethoscope is a medical instrument used for auscultation, or listening to body sounds, such as heartbeats and lung sounds. It is a fundamental tool in medical diagnostics. to check for abnormal heart sounds.

Additional diagnostic tests may include an electrocardiogramSee ECG. (ECG) to detect cardiac arrhythmiaAn arrhythmia is a heart rhythm disorder in which the heart beats irregularly, either too fast (tachycardia), too slow (bradycardia), or with an irregular pattern. Arrhythmias can be harmless or a sign of serious heart problems., as well as chest X-rays to assess the size of the heart and the condition of the lungs. An ultrasoundUltrasound refers to sound waves that are above the hearing threshold of the human ear. In medicine, ultrasound is used for diagnostic imaging procedures to visualize internal organs, tissues, and blood flow. of the heart (echocardiographyEchocardiography is an ultrasound examination of the heart that assesses the structure and function of the heart valves and chambers. It can provide information about heart size, pumping function, and the presence of heart disease.) is often the best way to examine the structure and function of the heart in detail and identify specific heart diseases.

Blood tests can also be performed to rule out other possible causes of the symptoms and to check for the presence of heart failure markers in the blood. The veterinarian will use the results of all tests to create a comprehensive treatment plan.

What can pet owners do and professional therapy options

As a pet owner, you can take several steps to relieve your dog’s symptoms and improve their quality of life. First, it is important to administer the medications prescribed by the veterinarian exactly as directed. These may include diuretics to reduce fluid build-up, ACE inhibitors to relieve the heart, or other heart-supporting medications.

The dog’s diet should also be adjusted. A low-salt diet can help reduce fluid retention. Your veterinarian may recommend special heart diets or supplements that support heart health.

Regular but not excessive exercise is important to support the cardiovascular system without overtaxing the dog. Gentle walks and controlled play can help maintain fitness. Be careful not to overexert the dog, especially in warm weather, as this can worsen their symptoms.

Monitor your dog closely and consult your veterinarian regularly to adjust the treatment plan as needed. Open communication with the veterinarian and following their recommendations are crucial for managing heart failure in dogs.

Outlook on current research

Research into heart failure in dogs is increasingly focused on early detection and effective treatment to improve the quality of life of affected animals. In recent years, diagnostic techniques such as echocardiographyEchocardiography is an ultrasound examination of the heart that assesses the structure and function of the heart valves and chambers. It can provide information about heart size, pumping function, and the presence of heart disease. and biomarker tests have proven to be valuable tools for identifying heart disease early. New studies are investigating the role of genetic factors and their influence on the predispositionA predisposition is an innate inclination or susceptibility of an organism to certain diseases or conditions. In dogs and cats, there may be a genetic predisposition to certain conditions such as hip dysplasia or certain heart diseases. of certain dog breeds to heart failure. The aim is to identify genetic markers that could increase susceptibility to heart disease.

Another focus of current research is the development of new drugs and therapyTherapy refers to the treatment of diseases or disorders with the aim of alleviating symptoms, promoting healing, or improving quality of life. Therapies can be medicinal, surgical, or through other medical interventions. approaches. Researchers are working on formulating drugs that specifically target the molecular mechanisms of heart failure to alleviate symptoms and slow the progressionProgression refers to the advancement or worsening of a disease over time. It describes an increase in the severity or extent of the disease symptoms. of the disease. A promising approach is the use of pacemakers or implantable defibrillators, which can help keep a dog’s heart in a more stable rhythm.

Regenerative medicine also offers new perspectives. Studies on stem cell therapy show potential to repair damaged heart tissue and improve function in dogs with heart failure. Although these approaches are still in the early stages of development, they could play a significant role in treatment in the future.

An increasingly important aspect is also nutrition. Researchers are investigating how special diets and nutritional supplements can help support heart health. Omega-3 fatty acids, antioxidants, and certain amino acids are being researched for their protective properties against heart failure. These nutritional strategies could play a complementary role in treatment and preventionPrevention includes measures taken to prevent diseases or injuries. In veterinary medicine, this includes vaccinations, parasite control, and health monitoring..

In summary, current research aims not only to treat the symptoms of heart failure in dogs, but also to better understand the underlying causes and develop innovative solutions to prolong the lives of affected dogs and improve their quality of life.

Frequently asked questions

What are the most common symptoms of heart failure in dogs? Common symptoms of heart failure in dogs include cough, shortness of breath, lethargy, loss of appetite, and in severe cases, fainting or collapse. These symptoms can vary depending on the severity of the condition.
Can all dog breeds suffer from heart failure? Yes, theoretically all dog breeds can suffer from heart failure, but certain breeds are more susceptible. Commonly affected breeds include Cavalier King Charles Spaniels, Dobermans, and Great Danes, as they are genetically more prone to heart disease.
How is heart failure diagnosed in dogs? DiagnosisA diagnosis is the identification of a disease or condition by its symptoms and/or results from diagnostic tests. It is the first step in the management and treatment of patients. is usually made through a combination of physical examination, X-rays, echocardiographyEchocardiography is an ultrasound examination of the heart that assesses the structure and function of the heart valves and chambers. It can provide information about heart size, pumping function, and the presence of heart disease., and blood tests. A veterinarian may also perform special biomarker tests to assess heart function.
What treatment options are available for dogs with heart failure? Treatment may include medications to control blood pressure and heart rate, as well as diureticsDiuretics are medications that increase urine production in the kidneys to rid the body of excess salt and water. They are often used to treat high blood pressure, heart failure, and certain types of edema. to reduce fluid build-up. In some cases, surgical procedures or the use of pacemakers may be necessary. An adapted diet can also be helpful.
Is heart failure curable in dogs? Heart failure in dogs is usually not curable, but it can often be successfully treated and managed to improve quality of life and prolong life. Early diagnosisA diagnosis is the identification of a disease or condition by its symptoms and/or results from diagnostic tests. It is the first step in the management and treatment of patients. and regular veterinary care are crucial.
How can I reduce the risk of heart failure in my dog? To reduce the risk, regular veterinary check-ups should be performed. A balanced diet, regular exercise, and avoiding overweight can also help promote heart health. A genetic test can also be useful for certain breeds.
How does diet affect heart failure in dogs? A balanced diet can support heart health by providing essential nutrients that strengthen the heart. Supplements such as omega-3 fatty acids or antioxidants can also help improve heart function and slow the progressionProgression refers to the advancement or worsening of a disease over time. It describes an increase in the severity or extent of the disease symptoms. of the disease.
Can stressStress refers to the state of an organism reacting to external stimuli or demands. In veterinary medicine, stress can have physical or psychological effects on animals, impacting their health and well-being. worsen heart failure in dogs? Yes, stressStress refers to the state of an organism reacting to external stimuli or demands. In veterinary medicine, stress can have physical or psychological effects on animals, impacting their health and well-being. can worsen the symptoms of heart failure. StressStress refers to the state of an organism reacting to external stimuli or demands. In veterinary medicine, stress can have physical or psychological effects on animals, impacting their health and well-being. increases heart rate and blood pressure, which puts additional strain on the heart. It is important to create a calm and stress-free environment for affected dogs.
What role does exercise play in dogs with heart failure? Adapted exercise is important to promote overall health, but it should be carefully monitored. Excessive exertion can be harmful, so activities should be coordinated with the veterinarian to ensure they are appropriate for the dog’s health condition.
Are regular check-ups necessary for heart failure? Yes, regular check-ups are crucial to monitor the course of the disease and adjust the therapyTherapy refers to the treatment of diseases or disorders with the aim of alleviating symptoms, promoting healing, or improving quality of life. Therapies can be medicinal, surgical, or through other medical interventions. if necessary. These visits help to detect complications early and maintain the dog’s quality of life.