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Slow Heart Rate (Bradycardia) in Dogs

Author: Dr. med. vet. Gisa Löwe | Last modified: 06.11.2025

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BradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease. is a medical condition in which a dog’s heart rate is below the normal range. In dogs, this low heart rate can vary depending on the breed, age, and size of the animal. In general, a heart rate below 60 to 70 beats per minute in large dogs and below 80 to 100 beats per minute in small dogs is considered bradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease..

Can Occur with the Following Diseases:

Basics and possible causes

A dog’s heart rate is regulated by the autonomic nervous system, which includes both the sympatheticIn medicine, sympathetic refers to the sympathetic nervous system, a part of the autonomic nervous system that prepares the body for "fight or flight" responses by increasing heart rate and blood pressure, among other things. and parasympathetic parts. The sympatheticIn medicine, sympathetic refers to the sympathetic nervous system, a part of the autonomic nervous system that prepares the body for "fight or flight" responses by increasing heart rate and blood pressure, among other things. part is responsible for increasing the heart rate, while the parasympathetic part, especially the vagus nerveThe vagus nerve is the tenth cranial nerve and plays a central role in the parasympathetic nervous system. It affects the function of many internal organs, including the control of heart rate, gastrointestinal motility, and respiration in dogs and cats., lowers the heart rate. Excessive activation of the vagus nerveThe vagus nerve is the tenth cranial nerve and plays a central role in the parasympathetic nervous system. It affects the function of many internal organs, including the control of heart rate, gastrointestinal motility, and respiration in dogs and cats. can therefore lead to bradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease..

BradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease. can be caused by a variety of factors. One of the most common reasons is a disturbance in the electrical system of the heart, such as in sick sinus syndromeA syndrome is a group of symptoms that occur together and indicate a specific disease or condition. A syndrome can be caused by various factors and is often complex in its diagnosis and treatment. or atrioventricular block. These problems can be either 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. or acquired.

Other causes include systemic diseases such as hypothyroidism, in which the thyroid gland does not produce enough hormones, or hypothermia, in which the dog’s body is hypothermic. Certain medications, especially those that affect the heart, such as beta-blockers or antiarrhythmics, can also lead to a reduced heart rate.

Poisoning, especially from certain pesticidesPesticides are chemical or biological substances used to control pests, including insects, weeds, and fungi. In dogs and cats, exposure to certain pesticides can be harmful to health and lead to signs of poisoning. or plants, can also cause bradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease.. In some cases, bradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease. may be a sign of a more serious heart condition or systemic disease that requires immediate veterinary intervention.

Typical accompanying symptoms

Weakness: Dogs with bradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease. may appear weak and lethargic due to reduced cardiac output. This results from an inadequate supply of oxygenated blood to the body.
Loss of consciousness: In severe cases, fainting or collapse may occur because the brain does not receive enough blood and oxygen.
RespiratoryRespiratory refers to breathing or the process of breathing. Respiratory diseases affect the respiratory tract and can impair the ability to breathe effectively. distress: Some dogs show respiratoryRespiratory refers to breathing or the process of breathing. Respiratory diseases affect the respiratory tract and can impair the ability to breathe effectively. distress or rapid, shallow breathing as the body tries to compensate for the lack of oxygen.
Pale gums: Reduced blood flow can lead to pale or bluish gums, which is a sign of poor oxygenation.
Altered heart sounds: During the examination, the veterinarian may detect abnormal heart sounds or an irregular heartbeat.

When to visit the vet?

A veterinary visit is urgently needed if your dog shows signs of weakness, fainting, 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. These symptoms may indicate a serious undersupply of blood and oxygen to the body and require immediate medical attention.

If you notice a change in your dog’s heart rate or if he seems unusually lethargic or weak, it is advisable to see a veterinarian as soon as possible. Even if the symptoms appear mild, they may be an indicator of an underlying problem that could worsen.

Symptom recognition for animal owners and veterinary diagnostic procedures

As a pet owner, you can check your dog’s heart rate at home by placing your hand on his chest and counting the number of heartbeats per minute. An unusually slow rate should be associated with other symptoms to decide if a veterinary visit is necessary.

The veterinarian will perform a thorough physical examination to assess your dog’s general health. An electrocardiogramSee ECG. (ECG) can be used to monitor the electrical activity of the heart and detect any abnormalities.

Blood tests can also be performed to look for systemic diseases or electrolyte imbalances that could affect heart rate. In some cases, further diagnostic imagingDiagnostic imaging includes medical procedures that create images of the inside of the body to diagnose, monitor, or treat diseases and injuries. Examples include X-ray, ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI). procedures, such as X-rays or 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, may be necessary to rule out structural problems.

What can pet owners do and professional therapy options

As a pet owner, it is important to remain calm and put your dog in a comfortable position if you notice signs of bradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease.. Avoid physical exertion and 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., which could worsen the situation.

If you know that your dog is taking medications that could affect his heart rate, check the dosage and consult your veterinarian to determine if an adjustment is necessary.

Make sure your dog stays hydrated, as dehydrationDehydration occurs when the body loses more fluid than it takes in. This can lead to a number of problems, including headaches, Dizziness, and in extreme cases, renal failure or Cardiovascular collapse. can impair heart function. Pay attention to a balanced diet to support your dog’s overall health.

In some cases, emergency treatment may be necessary, especially if your dog collapses or does not respond to external stimuli. Do not hesitate to seek immediate veterinary help to minimize the risk of serious consequences.

Outlook on current research

Research into bradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease. in dogs is increasingly focused on the genetic and environmental factors that can lead to a slow heart rate. Scientists are investigating the role of genetic predispositions, particularly in certain breeds that may be more susceptible to bradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease.. It is believed that genetic markers could be identified to help with early detection and provide veterinarians with valuable information to take preventive measures.

Another promising area of research is the development of new diagnostic technologies. Advances in wearable heart monitors and non-invasive measurement methods make it possible to monitor the heart activity of dogs over longer periods of time. These technologies can help detect subtle changes in heart rate that indicate the onset of bradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease. before clinical symptoms appear.

In addition, intensive research is being conducted into the development of drugs that specifically target the regulation of heart rate. These drugs could represent an alternative or complementary form of 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. to the currently existing treatments. Researchers are also investigating the effect of diets and nutritional supplements that could support the cardiovascular system to stabilize the heart rate in affected dogs.

In the field of preventionPrevention includes measures taken to prevent diseases or injuries. In veterinary medicine, this includes vaccinations, parasite control, and health monitoring., research is being conducted into how lifestyle changes can reduce the risk of bradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease.. Studies suggest that regular physical activity, weight management, and 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. reduction may have positive effects on heart health. These findings could lead to new guidelines for the care and keeping of dogs in the future to minimize the risk of bradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease..

Finally, the role of environmental factors and their influence on heart rate is being investigated. Environmental toxins, air pollution, and even noise pollution could potentially affect the heart health of dogs. Long-term studies are underway to better understand the effects of these factors and to develop appropriate protective measures.

Frequently asked questions

What is bradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease. in dogs? BradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease. is a medical term for a lower heart rate than normal. In dogs, this means that the heart beats slower than it should, which can lead to various health problems.
How do I know if my dog has a slow heart rate? Signs of bradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease. can include lethargy, weakness, fainting, respiratoryRespiratory refers to breathing or the process of breathing. Respiratory diseases affect the respiratory tract and can impair the ability to breathe effectively. distress, and decreased activity. If you suspect your dog may be affected, you should consult a veterinarian.
How is heart rate measured in dogs? Heart rate is typically measured by palpating the pulse on the inside of the thigh or 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.. Modern technologies also allow monitoring by wearable devices.
What are the causes of a slow heart rate in dogs? Causes can be genetic predispositions, certain medications, hypothyroidism, heart disease, or disorders of the autonomic nervous system. 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. must be made by a veterinarian.
Can all dog breeds be affected by bradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease.? Yes, all dog breeds can be affected by bradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease., but some breeds are at higher risk due to genetic factors. Regular check-ups can help detect risks early.
What treatment options are available for dogs with bradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease.? Treatment depends on the underlying cause and may include medications, pacemakers, or dietary adjustments. A veterinarian will determine the best course of action.
Is bradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease. curable in dogs? Whether bradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease. is curable depends on the underlying cause. Some forms can be resolved by treating the underlying disease, while others may require lifelong monitoring and treatment.
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. cause a slow heart rate 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 affect the cardiovascular system and theoretically contribute to a slow heart rate, although this is less common than other causes. 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. management can be part of the treatment.
What are the risks if bradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease. is left untreated in dogs? Untreated bradycardiaBradycardia refers to a slower than normal heart rate, typically below 60 beats per minute in adults. It can occur in healthy individuals, especially athletes, but can also be an indication of heart disease. can lead to serious complications such as heart failure, fainting, or sudden cardiac death. 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 treatment are crucial.
How can I support my dog’s heart health? To promote heart health, you should pay attention to a balanced diet, regular exercise, and regular veterinary examinations. 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. management and avoiding environmental toxins can also be helpful.