Home » Diseases » In dogs » Pulmonary Thromboembolism (Blockage of a Pulmonary Artery by a Blood Clot)

Pulmonary Thromboembolism (Blockage of a Pulmonary Artery by a Blood Clot) in Dogs

Occurrence: rarer
Location of disease: Chest

Author: Dr. med. vet. Gisa Löwe | Last modified: 17.02.2026

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Definition

PulmonaryPulmonary refers to the lungs or the respiratory system. Pulmonary diseases in dogs and cats include conditions such as Pneumonia, asthma, and pulmonary hypertension. thromboembolismThromboembolism is the blockage of a blood vessel by a blood clot (thrombus) that has formed in one place in the circulatory system and then moved to another location. This can lead to serious complications, such as a stroke or pulmonary embolism. in dogs is a condition in which a blood clot blocks one or more pulmonaryPulmonary refers to the lungs or the respiratory system. Pulmonary diseases in dogs and cats include conditions such as Pneumonia, asthma, and pulmonary hypertension. arteries, which can lead to reduced oxygen supply and potentially life-threatening complications.

The most important facts at a glance

Pulmonary thromboembolism in dogs is a serious condition caused by a blood clot in the pulmonaryPulmonary refers to the lungs or the respiratory system. Pulmonary diseases in dogs and cats include conditions such as Pneumonia, asthma, and pulmonary hypertension. arteries. These clots often form in the deep veins of the legs or pelvis and travel to the lungs. Main causes include Cushing’s 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., heart disease, cancerCancer refers to the uncontrolled proliferation of cells that can lead to tumors or spread throughout the body. Various types of cancer occur in dogs and cats, ranging from skin cancer to lymphomas., infections, traumas, and certain medications. Symptoms include weakness, cough, 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 pale or bluish mucous membranes. 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 made through clinical examination, imaging procedures like CT or MRI, and blood tests. Treatment focuses on stabilizing the dog, improving oxygen supply, and preventing new thrombi. AnticoagulantsAnticoagulants are medications that slow down or inhibit blood coagulation. They are used to prevent the formation of blood clots and are used in dogs and cats with certain heart conditions or coagulation disorders. such as heparin and warfarin are central, and oxygen 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. may be required in severe cases. The prognosisThe prognosis is the prediction of the likely course and outcome of a disease based on the general state of health, the nature of the disease, and the response to treatment. It can provide information on how a disease is expected to develop. depends on the blockage, the speed of 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, and underlying diseases. PreventionPrevention includes measures taken to prevent diseases or injuries. In veterinary medicine, this includes vaccinations, parasite control, and health monitoring. includes reducing risk factors, treating underlying diseases, and prophylactic measures for high-risk dogs. Research is investigating genetic predispositions, inflammatory processes, improved diagnostic techniques, and new medications. A balanced diet and a healthy weight can also help minimize the risk. Scientists are working to improve the understanding and treatment options for this complex disease.

Causes

Pulmonary thromboembolism is a serious condition caused by the formation of a blood clot, also known as a thrombusA thrombus is a blood clot that forms within the circulatory system and adheres to the vessel wall. Thrombi can obstruct blood flow and lead to various health problems., in the blood vessels of the lungs. These clots can develop in various parts of the body, but usually in the deep veins of the legs or pelvis, and then travel through the bloodstream to the lungs, where they block the arteries.

The formation of a thrombusA thrombus is a blood clot that forms within the circulatory system and adheres to the vessel wall. Thrombi can obstruct blood flow and lead to various health problems. is explained by a combination of three main factors known as Virchow’s triad: changes in blood composition (hypercoagulability), changes in blood flow (stasis), and damage to the vessel wall. In dogs, these factors can be caused by various diseases or conditions.

The most common causes of an increased tendency to clot in dogs include conditions such as Cushing’s 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., heart disease, cancerCancer refers to the uncontrolled proliferation of cells that can lead to tumors or spread throughout the body. Various types of cancer occur in dogs and cats, ranging from skin cancer to lymphomas., infections, traumas, and surgical procedures. Certain medications can also increase the risk of blood clots. Older dogs are at an increased risk of developing thrombi due to degenerative diseases.

Symptoms

Very common symptoms:

Common symptoms:

Symptoms of pulmonary thromboembolismThromboembolism is the blockage of a blood vessel by a blood clot (thrombus) that has formed in one place in the circulatory system and then moved to another location. This can lead to serious complications, such as a stroke or pulmonary embolism. in dogs can vary and depend on the size and number of affected arteries. The most common symptoms include sudden shortness of breath, an increased respiratoryRespiratory refers to breathing or the process of breathing. Respiratory diseases affect the respiratory tract and can impair the ability to breathe effectively. rate, and a bluish discoloration of the mucous membranes, indicating an insufficient oxygen supply.

Other possible symptoms include cough, weakness, collapse, or loss of consciousness, especially after physical exertion. In severe cases, 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 cardiovascular collapse may occur. Since these symptoms are non-specific, a quick and 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. is crucial for the dog’s survival.

Diagnosis

The 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. of pulmonaryPulmonary refers to the lungs or the respiratory system. Pulmonary diseases in dogs and cats include conditions such as Pneumonia, asthma, and pulmonary hypertension. thromboembolismThromboembolism is the blockage of a blood vessel by a blood clot (thrombus) that has formed in one place in the circulatory system and then moved to another location. This can lead to serious complications, such as a stroke or pulmonary embolism. in dogs requires a thorough clinical examination and usually the use of a combination of imaging techniques and laboratory tests. First, the veterinarian will take a detailed medical historyThe medical history is the systematic collection of a patient's medical history through questioning. It includes information about previous illnesses, treatments, allergies, and lifestyle habits. and evaluate the dog’s symptoms.

Chest X-rays can provide clues to changes in lung structure, but are often not sufficient to diagnose pulmonaryPulmonary refers to the lungs or the respiratory system. Pulmonary diseases in dogs and cats include conditions such as Pneumonia, asthma, and pulmonary hypertension. thromboembolismThromboembolism is the blockage of a blood vessel by a blood clot (thrombus) that has formed in one place in the circulatory system and then moved to another location. This can lead to serious complications, such as a stroke or pulmonary embolism. beyond doubt. A computed tomography (CT)Computed tomography (CT) is an imaging technique that uses X-rays and computer technology to create cross-sectional images of the body. It enables a detailed view of bones, organs, and other structures and is used for the diagnosis of injuries, diseases, and for planning medical interventions. or magnetic resonance imaging (MRI)Magnetic resonance imaging is an imaging technique that uses strong magnetic fields and radio waves to create detailed images of the inside of the body. It is used in veterinary medicine to diagnose diseases of the brain, spine, and other organs. of the chest can be helpful to directly visualize blood clots in the pulmonaryPulmonary refers to the lungs or the respiratory system. Pulmonary diseases in dogs and cats include conditions such as Pneumonia, asthma, and pulmonary hypertension. arteries.

Additionally, blood tests can be performed to evaluate the blood’s clotting ability and rule out other possible causes for the symptoms. A cardiac 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. can help identify underlying heart diseases that may increase the risk of thromboembolismThromboembolism is the blockage of a blood vessel by a blood clot (thrombus) that has formed in one place in the circulatory system and then moved to another location. This can lead to serious complications, such as a stroke or pulmonary embolism..

Therapy

Treatment of pulmonary thromboembolismThromboembolism is the blockage of a blood vessel by a blood clot (thrombus) that has formed in one place in the circulatory system and then moved to another location. This can lead to serious complications, such as a stroke or pulmonary embolism. in dogs aims to reduce the blockage of the pulmonaryPulmonary refers to the lungs or the respiratory system. Pulmonary diseases in dogs and cats include conditions such as Pneumonia, asthma, and pulmonary hypertension. arteries, improve oxygen supply, and prevent the formation of further blood clots. 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. usually begins with stabilizing the dog, especially in cases of severe 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 circulatory problems.

AnticoagulantsAnticoagulants are medications that slow down or inhibit blood coagulation. They are used to prevent the formation of blood clots and are used in dogs and cats with certain heart conditions or coagulation disorders., medications that inhibit blood coagulationBlood coagulation is a process that helps stop Bleeding when a blood vessel is damaged. Platelets and certain proteins in the plasma form a blood clot that seals the wound., are the cornerstone of treatment. Heparin and warfarin are commonly used medications that prevent the formation of new thrombi. In some cases, thrombolytics may be used to dissolve existing blood clots, but their use is limited due to side effects.

In addition to drug 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., oxygen 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. may be necessary in severe cases to ensure the dog’s oxygen supply. SupportiveSupportive refers to supportive treatments that aim to alleviate symptoms and improve quality of life without directly treating the underlying cause of the disease. measures such as fluid 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. and rest can also be important to reduce the strain on the cardiovascular system.

Prognosis and follow-up care

The prognosis of pulmonary thromboembolism in dogs depends on several factors, including the extent of the blockage, the speed of 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 the start of treatment, as well as the presence of underlying diseases. With prompt and appropriate treatment, many dogs can have a good prognosisThe prognosis is the prediction of the likely course and outcome of a disease based on the general state of health, the nature of the disease, and the response to treatment. It can provide information on how a disease is expected to develop., although there is a risk of recurrence.

Long-term medication to prevent further thrombi may be required, especially in dogs with chronic or recurring conditions that increase the risk of blood clots. Regular monitoring by a veterinarian is crucial to adjust the treatment and detect potential complications early.

Prevention

PreventionPrevention includes measures taken to prevent diseases or injuries. In veterinary medicine, this includes vaccinations, parasite control, and health monitoring. of pulmonary thromboembolismThromboembolism is the blockage of a blood vessel by a blood clot (thrombus) that has formed in one place in the circulatory system and then moved to another location. This can lead to serious complications, such as a stroke or pulmonary embolism. in dogs focuses on reducing risk factors and treating underlying diseases. 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 of diseases such as Cushing’s 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., heart disease, and cancerCancer refers to the uncontrolled proliferation of cells that can lead to tumors or spread throughout the body. Various types of cancer occur in dogs and cats, ranging from skin cancer to lymphomas. can reduce the risk of thrombosisThrombosis is the formation of a blood clot in a blood vessel that can obstruct or block blood flow. Thromboses can occur in veins (venous thrombosis) or arteries (arterial thrombosis)..

Avoiding risk factors, such as long-term lack of exercise, can also be helpful. For dogs at high risk of thromboembolismThromboembolism is the blockage of a blood vessel by a blood clot (thrombus) that has formed in one place in the circulatory system and then moved to another location. This can lead to serious complications, such as a stroke or pulmonary embolism., the veterinarian may consider prophylactic measures such as administering anticoagulant medications.

Regular veterinary monitoring and adherence to recommended treatment plans are crucial to minimize the risk of complications and maintain the dog’s health. In addition, attention should be paid to a balanced diet and a healthy weight to support the cardiovascular system.

Outlook on current research

Pulmonary thromboembolism in dogs is a serious medical problem that is becoming increasingly important in veterinary medicine. There are currently several lines of research focusing on the 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., treatment, and preventionPrevention includes measures taken to prevent diseases or injuries. In veterinary medicine, this includes vaccinations, parasite control, and health monitoring. of this disease. A large part of the research focuses on identifying predisposing factors. Some studies are investigating genetic predispositions and the role of inflammatory processes in the formation of blood clots to better define risk groups.

Another focus is on improving diagnostic procedures. In the past, diagnosing pulmonaryPulmonary refers to the lungs or the respiratory system. Pulmonary diseases in dogs and cats include conditions such as Pneumonia, asthma, and pulmonary hypertension. thromboembolismThromboembolism is the blockage of a blood vessel by a blood clot (thrombus) that has formed in one place in the circulatory system and then moved to another location. This can lead to serious complications, such as a stroke or pulmonary embolism. in dogs was often difficult and uncertain. Modern imaging techniques such as computed tomography (CT)Computed tomography (CT) is an imaging technique that uses X-rays and computer technology to create cross-sectional images of the body. It enables a detailed view of bones, organs, and other structures and is used for the diagnosis of injuries, diseases, and for planning medical interventions. and magnetic resonance imaging (MRI)Magnetic resonance imaging is an imaging technique that uses strong magnetic fields and radio waves to create detailed images of the inside of the body. It is used in veterinary medicine to diagnose diseases of the brain, spine, and other organs. are being increasingly researched to refine their application in diagnosing this disease. These methods could enable faster and more 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. in the future, which is crucial for timely treatment.

Research into treatment methods is also a central topic. Current studies are investigating new anticoagulantsAnticoagulants are medications that slow down or inhibit blood coagulation. They are used to prevent the formation of blood clots and are used in dogs and cats with certain heart conditions or coagulation disorders. and thrombolytics specifically developed for use in dogs. These medications could reduce the risk of complications and improve survival rates. In parallel, alternative therapeutic approaches such as the use of dietary supplements and herbal remedies are being explored, which may have supportiveSupportive refers to supportive treatments that aim to alleviate symptoms and improve quality of life without directly treating the underlying cause of the disease. effects.

The preventionPrevention includes measures taken to prevent diseases or injuries. In veterinary medicine, this includes vaccinations, parasite control, and health monitoring. of pulmonaryPulmonary refers to the lungs or the respiratory system. Pulmonary diseases in dogs and cats include conditions such as Pneumonia, asthma, and pulmonary hypertension. thromboembolismThromboembolism is the blockage of a blood vessel by a blood clot (thrombus) that has formed in one place in the circulatory system and then moved to another location. This can lead to serious complications, such as a stroke or pulmonary embolism. is also a focus of research. Scientists are investigating the possibility of reducing the risk of blood clot formation through targeted changes in diet and lifestyle. Studies on the role of omega-3 fatty acids and other nutrients could be helpful in preventionPrevention includes measures taken to prevent diseases or injuries. In veterinary medicine, this includes vaccinations, parasite control, and health monitoring.. This research could contribute to lowering the incidenceIncidence refers to the number of new cases of a disease or condition that occur within a specific time period in a specific population group. It provides information about the risk of contracting the disease. of this disease in dogs in the long term.

In summary, research on pulmonaryPulmonary refers to the lungs or the respiratory system. Pulmonary diseases in dogs and cats include conditions such as Pneumonia, asthma, and pulmonary hypertension. thromboembolismThromboembolism is the blockage of a blood vessel by a blood clot (thrombus) that has formed in one place in the circulatory system and then moved to another location. This can lead to serious complications, such as a stroke or pulmonary embolism. in dogs is making progress in several areas. From genetic research to improving diagnostic techniques and developing new medications and preventionPrevention includes measures taken to prevent diseases or injuries. In veterinary medicine, this includes vaccinations, parasite control, and health monitoring. strategies, scientists worldwide are working to deepen the understanding of this complex disease and optimize treatment options.

Frequently asked questions (FAQs)

What is pulmonary thromboembolism in dogs?

Pulmonary thromboembolism occurs when a blood clot blocks one or more arteries in the lungs. This can lead to shortness of breath and other serious health problems.

What symptoms does a dog with pulmonary thromboembolism show?

Symptoms can include shortness of breath, cough, rapid breathing, weakness, collapse, or even sudden Death. These symptoms require immediate veterinary care.

Which dogs are most at risk of developing pulmonary thromboembolism?

Dogs with certain pre-existing conditions such as heart disease, cancer, or inflammatory diseases have an increased risk. Older dogs are also more frequently affected.

How is pulmonary thromboembolism diagnosed in dogs?

Diagnosis is usually made through a combination of clinical examinations, blood tests, and imaging procedures such as X-ray or CT scans.

What are the treatment options for pulmonary thromboembolism in dogs?

Treatment may include the administration of oxygen, anticoagulants, pain relievers, and in some cases, surgical procedures. The exact therapy depends on the severity of the disease.

Can pulmonary thromboembolism be prevented in dogs?

While not all cases can be prevented, measures such as the management of underlying diseases, a balanced diet, and regular exercise can reduce the risk.

Are there complications that can occur after pulmonary thromboembolism in dogs?

Yes, possible complications include Heart failure, pulmonary infarction, and chronic respiratory distress. Early diagnosis and treatment can help minimize these.

How long does it take for a dog to recover from pulmonary thromboembolism?

Recovery time varies depending on the severity of the disease and the treatment, but can take weeks to months. Follow-up care by a veterinarian is crucial.

Are certain breeds more susceptible to pulmonary thromboembolism?

While all dogs can be affected, there are no specific breeds that are significantly more susceptible. The risk depends more on individual health factors.

What should I do if I suspect symptoms of pulmonary thromboembolism in my dog?

Seek veterinary help immediately. A quick diagnosis and treatment are crucial to ensure the dog's survival and recovery.