Home » Diseases » In cats » Pectus Excavatum (Deformed Sternum, Funnel Chest)

Pectus Excavatum (Deformed Sternum, Funnel Chest) in cats

Occurrence: very rare
Location of illness: Chest

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

When to visit the vet?

Non-urgent see a veterinarian within 2–3 days

If the condition worsens / symptoms persist, consult a veterinarian.

Definition

Pectus excavatum, also known as funnel chest or deformed sternumThe sternum, or breastbone, is a long, flat bone in the center of the chest where the ribs are attached. It plays an essential role in protecting the heart and other organs in the chest., is a 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. malformation of the chest wall in cats, in which the sternumThe sternum, or breastbone, is a long, flat bone in the center of the chest where the ribs are attached. It plays an essential role in protecting the heart and other organs in the chest. is curved inward, causing a depressionDepression refers to a state of reduced mood and activity. In dogs and cats, it can be triggered by various factors, including illness, trauma, or changes in the environment. in the chest.

The most important facts at a glance

Pectus excavatum, also known as funnel chest, is a deformityA deformity is an abnormal shape or structure of a body part, often due to genetic factors, injuries, or diseases. Deformities can impair function and may require cosmetic or medical treatment. of the sternumThe sternum, or breastbone, is a long, flat bone in the center of the chest where the ribs are attached. It plays an essential role in protecting the heart and other organs in the chest. in cats whose exact cause is not fully understood, but genetic factors appear to play a significant role. This anomalyAn anomaly is a deviation from what is considered normal or expected. In medicine, it often refers to unusual physical or genetic characteristics that may be present at birth or develop later. often occurs in young cats and is caused by disrupted growth of the sternumThe sternum, or breastbone, is a long, flat bone in the center of the chest where the ribs are attached. It plays an essential role in protecting the heart and other organs in the chest. and ribs, leading to an indentation of the chest. Uneven tension in the muscles between the ribs and sternumThe sternum, or breastbone, is a long, flat bone in the center of the chest where the ribs are attached. It plays an essential role in protecting the heart and other organs in the chest., as well as inadequate nutrition during pregnancy, can also contribute to its development. The most common symptoms are respiratoryRespiratory refers to breathing or the process of breathing. Respiratory diseases affect the respiratory tract and can impair the ability to breathe effectively. distress, reduced stamina, and growth disorders, while rarer symptoms can include lung infections and loss of appetite.

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 physical examination and imaging procedures such as X-rays to assess the degree of indentation and its effects on the lungs and heart. Treatment depends on the severity and ranges from regular monitoring to surgical correction to improve chest shape. 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 physiotherapyVeterinary physiotherapy encompasses a range of treatment methods aimed at improving the mobility and well-being of animals through exercise, massage, and other manual techniques. and a balanced diet are also important. 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. is usually favorable with early detection and treatment, while severe cases without treatment can lead to respiratoryRespiratory refers to breathing or the process of breathing. Respiratory diseases affect the respiratory tract and can impair the ability to breathe effectively. and heart problems. PreventionPrevention includes measures taken to prevent diseases or injuries. In veterinary medicine, this includes vaccinations, parasite control, and health monitoring. includes responsible breeding practices and a balanced diet during pregnancy.

Causes

The exact cause of pectus excavatum is not fully understood, but genetic factors are believed to play a significant role. This deformityA deformity is an abnormal shape or structure of a body part, often due to genetic factors, injuries, or diseases. Deformities can impair function and may require cosmetic or medical treatment. occurs due to disrupted growth of the sternumThe sternum, or breastbone, is a long, flat bone in the center of the chest where the ribs are attached. It plays an essential role in protecting the heart and other organs in the chest. and ribs, leading to an unnatural indentation of the chest. In cats, especially young animals, this anomalyAn anomaly is a deviation from what is considered normal or expected. In medicine, it often refers to unusual physical or genetic characteristics that may be present at birth or develop later. can be 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. and become noticeable in the first weeks of life.

Another factor that can contribute to the development of Pectus excavatum is uneven tension in the intercostal muscles that connect the ribs to the sternumThe sternum, or breastbone, is a long, flat bone in the center of the chest where the ribs are attached. It plays an essential role in protecting the heart and other organs in the chest.. These muscles play a crucial role in breathing, and uneven muscle development can exacerbate the deformation. There is also evidence that inadequate nutrition or a lack of certain nutrients during pregnancy can increase the risk of this malformation.

Although genetic predispositions play a role, there are no clearly identified genes that can be held responsible for pectus excavatum. Researchers suspect it is a polygenetic disease involving multipleMultiple means manifold or repeated and is used to describe conditions or events that occur in multiple instances or at different locations. In veterinary medicine, this may indicate multiple lesions, tumors, or other pathological changes. genes. Environmental factors could also play a role by influencing gene expression.

Symptoms

Very common symptoms:

Common symptoms:

Rare symptoms:

The symptoms of Pectus excavatum can vary depending on the severity of the deformation. In mild cases, the cat may not show any obvious symptoms and the condition is often discovered accidentally during a routine examination. In more severe cases, however, clear signs may occur that impair the well-being and quality of life of the affected cat.

The most common symptoms include respiratoryRespiratory refers to breathing or the process of breathing. Respiratory diseases affect the respiratory tract and can impair the ability to breathe effectively. distress, especially during physical activity. Affected cats may show shallow and rapid breathing, as the deformation of the chest hinders the normal expansion of the lungs. In some cases, heart problems can also occur, as the pressure on the chest cavity can affect the heart.

Another symptom is reduced physical activity. Cats with Pectus excavatum may show a reduced desire to play and fatigue with minor exertion. In severe cases, growth disorders can occur, as the deformation restricts the space for the internal organs, which can affect food intake and processing.

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 pectus excavatum is usually made through a physical examination and imaging procedures. An experienced veterinarian can often detect the deformityA deformity is an abnormal shape or structure of a body part, often due to genetic factors, injuries, or diseases. Deformities can impair function and may require cosmetic or medical treatment. by palpating the chest. The degree of indentation can be assessed by visual inspection and palpationPalpation is an examination method in which the condition of body tissues is assessed by feeling them with the hands. It is used to identify swelling, pain, or other abnormalities.. To confirm 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. and assess the severity of the condition, chest X-rays are usually required.

X-rays clearly show the indentation of the sternumThe sternum, or breastbone, is a long, flat bone in the center of the chest where the ribs are attached. It plays an essential role in protecting the heart and other organs in the chest. and allow for an assessment of the effects on the lungs and heart. In some cases, 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. examination may be necessary to check heart function and rule out possible complications such as fluid accumulation or heart failure. Imaging also aids in planning potential surgical correction.

Therapy

The treatment of Pectus excavatum depends on the severity of the deformation and the associated symptoms. In mild cases that do not cause clinical symptoms, regular monitoring may be sufficient to ensure that the condition does not worsen. In more severe cases, surgical correction may be necessary to improve the shape of the chest and support respiratoryRespiratory refers to breathing or the process of breathing. Respiratory diseases affect the respiratory tract and can impair the ability to breathe effectively. and heart function.

One surgical option is the so-called “sternal elevation”, in which the sternumThe sternum, or breastbone, is a long, flat bone in the center of the chest where the ribs are attached. It plays an essential role in protecting the heart and other organs in the chest. is lifted by a surgical procedure to restore the normal shape of the chest. This procedure can be particularly effective in young cats whose bones are still growing. Another method is the use of an external compression device that is worn over a period of time to gradually correct the shape of the chest.

In addition to surgical treatment, 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 physiotherapyVeterinary physiotherapy encompasses a range of treatment methods aimed at improving the mobility and well-being of animals through exercise, massage, and other manual techniques. and special breathing exercises can help improve respiratoryRespiratory refers to breathing or the process of breathing. Respiratory diseases affect the respiratory tract and can impair the ability to breathe effectively. function. A balanced diet and avoiding 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. factors are also important to support the health of the affected cat.

Prognosis and follow-up care

The prognosis for cats with pectus excavatum depends on various factors, including the severity of the deformityA deformity is an abnormal shape or structure of a body part, often due to genetic factors, injuries, or diseases. Deformities can impair function and may require cosmetic or medical treatment. and the cat’s age at 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.. With early detection and appropriate treatment, especially in young cats, 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. is generally favorable. Surgical correction can significantly improve quality of life and normalize life expectancy.

Without treatment, more severe cases can lead to permanent respiratoryRespiratory refers to breathing or the process of breathing. Respiratory diseases affect the respiratory tract and can impair the ability to breathe effectively. and heart problems that can significantly impair the quality of life and shorten life expectancy. Regular follow-up examinations with the veterinarian are important to monitor the progress of the disease and to detect complications early.

Prevention

The preventionPrevention includes measures taken to prevent diseases or injuries. In veterinary medicine, this includes vaccinations, parasite control, and health monitoring. of pectus excavatum in cats is challenging, as the exact cause of this deformityA deformity is an abnormal shape or structure of a body part, often due to genetic factors, injuries, or diseases. Deformities can impair function and may require cosmetic or medical treatment. is not fully understood and it is often genetically determined. An important step in preventing this condition is responsible breeding practices. Breeders should ensure that cats with a known 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. for pectus excavatum are not used for breeding to minimize the risk of passing on this deformityA deformity is an abnormal shape or structure of a body part, often due to genetic factors, injuries, or diseases. Deformities can impair function and may require cosmetic or medical treatment..

A balanced diet during pregnancy can also play a role in preventionPrevention includes measures taken to prevent diseases or injuries. In veterinary medicine, this includes vaccinations, parasite control, and health monitoring.. Pregnant cats should receive food that contains all essential nutrients in sufficient quantities to support the healthy development of the fetuses. This can help reduce the risk of developmental anomalies, including pectus excavatum.

Early veterinary examinations of newborn kittens are crucial. Early detection makes it possible to take quick action to minimize the effects of the disease. Regular check-ups for young kittens can help identify deformations in the chest area early. Sensible education of cat owners about the signs of this disease can also help ensure that affected kittens receive veterinary help in good time.

Outlook on current research

Current research on pectus excavatum in cats focuses on the genetic factors that lead to the development of this chest deformityA deformity is an abnormal shape or structure of a body part, often due to genetic factors, injuries, or diseases. Deformities can impair function and may require cosmetic or medical treatment.. Scientists are investigating whether there are specific genetic markers that are more common in cats with this condition. InitialInitial means beginning or at the start. In medicine, it can refer to the first symptoms of a disease or the first phase of a treatment process. studies suggest there may be a hereditary component, which is not yet fully understood. Collecting genetic data from affected and unaffected cats could help paint a clearer picture and develop targeted breeding programs to reduce the risk of this deformityA deformity is an abnormal shape or structure of a body part, often due to genetic factors, injuries, or diseases. Deformities can impair function and may require cosmetic or medical treatment..

Another area of research is the investigation of environmental factors that could contribute to the development of pectus excavatum. These include, for example, conditions during pregnancy, the mother cat’s nutrition, or possible traumas in the early developmental stages of kittens. Identifying such factors could lead to better preventionPrevention includes measures taken to prevent diseases or injuries. In veterinary medicine, this includes vaccinations, parasite control, and health monitoring. strategies.

Regarding treatment options, intensive work is being done on the further development of surgical techniques. Currently, one of the most common treatment approaches is surgical correction by placing an orthopedic device that pushes the sternumThe sternum, or breastbone, is a long, flat bone in the center of the chest where the ribs are attached. It plays an essential role in protecting the heart and other organs in the chest. into a normal position. New minimally invasiveInvasive describes medical procedures or pathogens that enter the body or penetrate tissue. In medicine, invasive procedures can range from minimally invasive techniques to open surgery. techniques are being tested to make the procedure less stressful for the animals and shorten recovery times. The use of 3D printing technologies for manufacturing individual corrective devices is also being explored.

Additionally, the role of physiotherapyVeterinary physiotherapy encompasses a range of treatment methods aimed at improving the mobility and well-being of animals through exercise, massage, and other manual techniques. as a supportiveSupportive refers to supportive treatments that aim to alleviate symptoms and improve quality of life without directly treating the underlying cause of the disease. form of treatment is being investigated. InitialInitial means beginning or at the start. In medicine, it can refer to the first symptoms of a disease or the first phase of a treatment process. results show that targeted breathing exercises and muscle strengthening programs can improve the quality of life for affected cats. By combining surgical and non-surgical measures, better long-term treatment outcomes could be achieved.

Long-term studies are underway to better understand the effects of pectus excavatum on the lifespan and quality of life of cats. The collected data aims to help improve 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. for affected cats and support veterinarians in advising cat owners. These comprehensive investigations contribute to deepening the understanding of the disease and developing the best possible treatment approaches.

Frequently asked questions (FAQs)

What is Pectus excavatum in cats? Pectus excavatum, also known as funnel chest, is a 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. deformityA deformity is an abnormal shape or structure of a body part, often due to genetic factors, injuries, or diseases. Deformities can impair function and may require cosmetic or medical treatment. of the chest in which the sternumThe sternum, or breastbone, is a long, flat bone in the center of the chest where the ribs are attached. It plays an essential role in protecting the heart and other organs in the chest. is curved inward. This deformityA deformity is an abnormal shape or structure of a body part, often due to genetic factors, injuries, or diseases. Deformities can impair function and may require cosmetic or medical treatment. can affect the heart and lungs and lead to respiratoryRespiratory refers to breathing or the process of breathing. Respiratory diseases affect the respiratory tract and can impair the ability to breathe effectively. distress.
How can you recognize Pectus excavatum in cats? 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 physical examination and imaging procedures such as X-rays. Symptoms can include shortness of breath, reduced activity, and growth disorders.
Is Pectus excavatum treatable in cats? Yes, there are various treatment options, including surgical interventions to correct the deformityA deformity is an abnormal shape or structure of a body part, often due to genetic factors, injuries, or diseases. Deformities can impair function and may require cosmetic or medical treatment.. In mild cases, conservative treatment with physiotherapyVeterinary physiotherapy encompasses a range of treatment methods aimed at improving the mobility and well-being of animals through exercise, massage, and other manual techniques. may also be considered.
Which cat breeds are most commonly affected? Pectus excavatum can occur in any cat breed, but some studies suggest that it is more common in breeds such as the Siamese and Burmese.
Can Pectus excavatum be inherited? There is evidence that genetic factors may play a role, but the exact mechanisms are not yet fully understood. Further research is needed to clarify the heritability.
What risks are associated with surgical treatment? As with any surgical procedure, there are risks such as infections, bleeding, and reactions to anesthesiaAnesthesia refers to the state of insensitivity to pain and can be partial (local anesthesia) or for the entire body (general anesthesia). It is used to keep patients pain-free during surgical procedures.. Nevertheless, in many cases, the potential benefits of correction outweigh these risks.
Can cats with Pectus excavatum lead a normal life? With the right treatment and care, many cats with Pectus excavatum can lead a relatively normal life, especially if the disease is detected and treated early.
What role does nutrition play in the treatment? A balanced diet is important for the general well-being of the cat, but cannot directly influence Pectus excavatum. In some cases, a special diet may be recommended to support recovery after surgery.
Are there alternative treatment methods? In addition to surgical correction, breathing exercises, physical 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 in some cases, the use of special corsets can be employed as 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.
How can Pectus excavatum be prevented? Targeted breeding practices that consider genetic predispositions could help reduce the risk. Additionally, pregnant cats should receive optimal care to ensure the best possible conditions for kitten development.

Frequently asked questions (FAQs)

1. What is Pectus excavatum in cats?

Pectus excavatum, also known as funnel chest, is a congenital deformity of the chest in which the sternum is curved inward. This deformity can affect the heart and lungs and lead to respiratory distress.

2. How can you recognize Pectus excavatum in cats?

Diagnosis is usually made through a physical examination and imaging procedures such as X-rays. Symptoms can include shortness of breath, reduced activity, and growth disorders.

3. Is Pectus excavatum treatable in cats?

Yes, there are various treatment options, including surgical interventions to correct the deformity. In mild cases, conservative treatment with physiotherapy may also be considered.

4. Which cat breeds are most commonly affected?

Pectus excavatum can occur in any cat breed, but some studies suggest that it is more common in breeds such as the Siamese and Burmese.

5. Can Pectus excavatum be inherited?

There is evidence that genetic factors may play a role, but the exact mechanisms are not yet fully understood. Further research is needed to clarify the heritability.

6. What risks are associated with surgical treatment?

As with any surgical procedure, there are risks such as infections, bleeding, and reactions to anesthesia. Nevertheless, in many cases, the potential benefits of correction outweigh these risks.

7. Can cats with Pectus excavatum lead a normal life?

With the right treatment and care, many cats with Pectus excavatum can lead a relatively normal life, especially if the disease is detected and treated early.

8. What role does nutrition play in the treatment?

A balanced diet is important for the general well-being of the cat, but cannot directly influence Pectus excavatum. In some cases, a special diet may be recommended to support recovery after surgery.

9. Are there alternative treatment methods?

In addition to surgical correction, breathing exercises, physical therapy, and in some cases, the use of special corsets can be employed as supportive measures.

10. How can Pectus excavatum be prevented?

Targeted breeding practices that consider genetic predispositions could help reduce the risk. Additionally, pregnant cats should receive optimal care to ensure the best possible conditions for kitten development.