Home » Diseases » In cats » Peritoneopericardial Diaphragmatic Hernia (diaphragmatic hernia with an open connection between the abdominal cavity and the pericardial sac)

Peritoneopericardial Diaphragmatic Hernia (diaphragmatic hernia with an open connection between the abdominal cavity and the pericardial sac) in cats

Occurrence: very rare
Location of illness: Chest

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

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Urgent see a veterinarian within 24 hours

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

Definition

A peritoneopericardial diaphragmatic hernia (PPDH) in cats 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 in which there is an abnormal opening in the diaphragm that creates a connection between the abdominalThe term “abdominal” refers to anything that concerns the belly or the abdomen. It is an adjectival expression used to describe the location, symptoms, or conditions that occur in the abdominal area. cavity and the pericardialPericardial refers to anything related to the pericardium, the sac that surrounds and protects the heart. Pericardial diseases can affect heart function and often require specialized veterinary care. sac.

The most important facts at a glance

A peritoneopericardial diaphragmatic hernia (PPDH) is a condition in which an opening in the diaphragm creates a connection between the abdominalThe term "abdominal" refers to anything that concerns the belly or the abdomen. It is an adjectival expression used to describe the location, symptoms, or conditions that occur in the abdominal area. cavity and the pericardialPericardial refers to anything related to the pericardium, the sac that surrounds and protects the heart. Pericardial diseases can affect heart function and often require specialized veterinary care. sac. In cats, this condition is usually 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 results from a faulty fusion of tissue structures during embryonic development. This allows organs such as the liver, stomach, or intestines to enter the pericardialPericardial refers to anything related to the pericardium, the sac that surrounds and protects the heart. Pericardial diseases can affect heart function and often require specialized veterinary care. sac. Traumatic causes are rarer but can occur due to accidents or falls.

Symptoms of PPDH in cats can include Vomiting, RespiratoryRespiratory refers to breathing or the process of breathing. Respiratory diseases affect the respiratory tract and can impair the ability to breathe effectively. distress, 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 Weight loss. 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. is made through a clinical examination, followed by imaging procedures such as X-rayX-ray is an imaging technique that uses X-rays to create images of the inside of the body. It is often used to diagnose bone fractures, lung diseases, and other conditions. 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. to detect the displacement of organs. In complex cases, CT or MRI may be required. Treatment usually consists of surgical correction, in which the organs are repositioned and the diaphragm is closed. Careful postoperativePostoperative refers to the time after a surgical operation. This phase includes recovery and the management of possible complications after the procedure. care is crucial to avoid complications.

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 age and severity of the disease, but is generally good with 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. Preventive measures are difficult due to the 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. nature of the disease, but responsible breeding practices and regular veterinary examinations can help. Research focuses on genetic causes, diagnostic techniques, and surgical improvements to enhance the quality of life for affected cats.

Causes

The diaphragm is a muscular partition that separates the thoracic cavity from the abdominalThe term "abdominal" refers to anything that concerns the belly or the abdomen. It is an adjectival expression used to describe the location, symptoms, or conditions that occur in the abdominal area. cavity. It plays an essential role in respiration by contracting and relaxing to ventilate the lungs. In PPDH, the diaphragm is compromised by an opening that is either caused by a developmental disorder during the embryonic phase or by traumaA trauma refers to a physical injury or damage caused by external force. Traumas can range from simple cuts to severe multiple injuries.. In most cases in cats, this hernia is 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..

During embryonic development, various tissue structures fuse to form the diaphragm. Faulty fusion can lead to a persistentPersistent means lasting or continuing for an extended period. In veterinary medicine, it can refer to chronic diseases or symptoms that do not subside. opening that allows abdominalThe term "abdominal" refers to anything that concerns the belly or the abdomen. It is an adjectival expression used to describe the location, symptoms, or conditions that occur in the abdominal area. organs to enter the pericardialPericardial refers to anything related to the pericardium, the sac that surrounds and protects the heart. Pericardial diseases can affect heart function and often require specialized veterinary care. sac. Organs that may be affected often include the liver, stomach, intestines, and spleen. This condition can occur in cats of all breeds but appears to be more common in certain breeds, such as the Maine Coon.

Traumatic causes, although rarer in cats compared to 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. cases, can arise from accidents, such as car accidents or falls from great heights. These traumas can tear the diaphragm and create a similar connection between the abdominalThe term "abdominal" refers to anything that concerns the belly or the abdomen. It is an adjectival expression used to describe the location, symptoms, or conditions that occur in the abdominal area. and thoracic cavities.

Symptoms

Very common symptoms:

Common symptoms:

The symptoms of a PPDH can vary greatly, depending on which organs are affected and how severe the lesion is. Some cats show no symptoms at all, and the condition is discovered incidentally during a routine examination. Others, however, may have serious health problems.

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 due to impaired lung function caused by the displacement of organs into the thoracic cavity. Cats may also show cough, decreased appetite, vomiting, or weight loss. In some cases, significant abdominalThe term “abdominal” refers to anything that concerns the belly or the abdomen. It is an adjectival expression used to describe the location, symptoms, or conditions that occur in the abdominal area. swelling may occur if the stomach or intestines are affected. Decreased activity and lethargy are also frequently observed.

In more 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. may occur due to the physical proximity of organs to the heart. This can lead to circulatory problems and, in extreme cases, collapse.

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 PPDH usually begins with a thorough clinical examination and 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.. The veterinarian will look for signs such as 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 unusual heart sounds. However, imaging techniques are crucial for making 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..

Chest X-rays can often show the displacement of organs into the thoracic cavity. LateralLateral refers to the side of the body or a body part, as opposed to medial, which describes a position closer to the midline of the body. In veterinary medicine, it is used to describe the location of structures or injuries. and dorsoventral views are particularly helpful, as they can clarify the position and extent of the hernia. 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 can provide additional information, especially regarding the involvement of the liver and other soft tissues.

In some cases, 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. may be necessary to obtain detailed images of the anatomyAnatomy is the scientific study of the structure of living things. It deals with the construction and organization of organisms, including their systems, organs, and tissues.. These methods are particularly helpful in determining the exact location of the hernia and the structures involved.

Therapy

Treatment of a PPDH in cats usually requires surgery. The surgery aims to return the abdominalThe term "abdominal" refers to anything that concerns the belly or the abdomen. It is an adjectival expression used to describe the location, symptoms, or conditions that occur in the abdominal area. organs to their normal position and close the opening in the diaphragm. The procedure is technically demanding and should be performed by an experienced veterinary surgeon.

Before surgery, the cat is usually stabilized, especially if it is suffering from 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. The surgical technique may vary depending on the severity of the hernia, but it usually involves accessing the abdominalThe term "abdominal" refers to anything that concerns the belly or the abdomen. It is an adjectival expression used to describe the location, symptoms, or conditions that occur in the abdominal area. cavity to reposition the organs and closing the diaphragm.

Postoperatively, the cat requires careful monitoring to avoid complications such as infections or recurrence of the hernia. Pain management and an adapted diet are also important components of aftercare.

Prognosis and follow-up care

The prognosis for cats with PPDH depends on several factors, including the cat’s age, the severity of the hernia, and the promptness of treatment. Cats that are diagnosed and treated early generally 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..

However, if the hernia is detected late or if the cat already shows severe symptoms, 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. may be more guarded. Complications during or after surgery can impair recovery, but with appropriate veterinary care, the chance of a full recovery is high.

Prevention

The preventionPrevention includes measures taken to prevent diseases or injuries. In veterinary medicine, this includes vaccinations, parasite control, and health monitoring. of peritoneopericardial diaphragmatic hernia in cats is a challenge, as this condition is often 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.. Nevertheless, there are some measures that can reduce the risk. Responsible breeding is crucial. Breeders should ensure they only mate healthy animals without 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 this condition. A thorough veterinary examination should be performed before breeding to detect possible anomalies early.

Regular veterinary examinations can help identify early signs or symptoms that may indicate a hernia. A balanced diet and a healthy weight help promote the cat’s overall health and can reduce the risk of complications if a hernia is present.

For cat owners, it is important to make their pets’ environment safe to avoid accidents that could lead to injuries, as traumas can increase the risk of hernias. A safe environment and avoiding excessive stress can also help protect the cat’s health. Despite these measures, it remains important to stay in close contact with the veterinarian to ensure the best possible care.

Outlook on current research

Peritoneopericardial diaphragmatic hernia (PPDH) 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 in which there is a defect in the membrane that separates the abdominalThe term "abdominal" refers to anything that concerns the belly or the abdomen. It is an adjectival expression used to describe the location, symptoms, or conditions that occur in the abdominal area. cavity from the thoracic cavity. This leads to a direct connection between the abdominalThe term "abdominal" refers to anything that concerns the belly or the abdomen. It is an adjectival expression used to describe the location, symptoms, or conditions that occur in the abdominal area. cavity and the pericardialPericardial refers to anything related to the pericardium, the sac that surrounds and protects the heart. Pericardial diseases can affect heart function and often require specialized veterinary care. sac. In cats, this condition is rare, but there is some research focusing on its genetic basis, diagnostic methods, and treatment options.

Current research is investigating genetic factors that could contribute to the development of PPDH. Since the condition is 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., it is suspected that genetic mutations or inheritance patterns play a role. Researchers are working to identify specific genes associated with the occurrence of PPDH in cats to better understand how the disease develops and how it might be prevented.

Another focus of research is on improving diagnostic techniques. The use of imaging techniques such as ultrasound, X-rayX-ray is an imaging technique that uses X-rays to create images of the inside of the body. It is often used to diagnose bone fractures, lung diseases, and other conditions., 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. is being further developed to facilitate the detection of PPDH. These technologies help determine the exact location and extent of the hernia, which is crucial for planning a surgical procedure.

Surgical correction is currently the preferred treatment method for PPDH, and intensive efforts are being made to optimize surgical techniques. Studies are focusing on 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 that can reduce the risk of complications and shorten the recovery time for affected animals. Researchers are also investigating postoperativePostoperative refers to the time after a surgical operation. This phase includes recovery and the management of possible complications after the procedure. care protocols to improve the recovery and well-being of the animals.

Long-term studies are underway to evaluate the quality of life and survival of cats after PPDH treatment. These studies help veterinarians provide recommendations for aftercare and better understand long-term prognoses. Continuous research can steadily improve the understanding and management of PPDH, ultimately leading to better treatment outcomes for affected cats.

Frequently asked questions (FAQs)

What is a Peritoneopericardial Diaphragmatic Hernia (PPDH) in cats? A PPDH 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 in which there is a defect in the diaphragm that leads to a direct connection between the abdominalThe term "abdominal" refers to anything that concerns the belly or the abdomen. It is an adjectival expression used to describe the location, symptoms, or conditions that occur in the abdominal area. cavity and the pericardialPericardial refers to anything related to the pericardium, the sac that surrounds and protects the heart. Pericardial diseases can affect heart function and often require specialized veterinary care. sac. This can cause abdominalThe term "abdominal" refers to anything that concerns the belly or the abdomen. It is an adjectival expression used to describe the location, symptoms, or conditions that occur in the abdominal area. organs to enter the chest cavity.
How common is PPDH in cats? PPDH is a relatively rare condition in cats. The exact frequency is not known, but it is believed to be more common in certain breeds such as Maine Coon and Persian cats.
What symptoms occur in cats with PPDH? The symptoms can vary, but often include vomiting, cough, loss of appetite, vomiting, weight loss, and lethargy. However, some cats show no symptoms until the condition is discovered incidentally during a routine examination.
How is PPDH diagnosed? PPDH is usually diagnosed through imaging techniques such as X-ray, ultrasound, or MRI. These techniques allow for visualizing the position of abdominalThe term "abdominal" refers to anything that concerns the belly or the abdomen. It is an adjectival expression used to describe the location, symptoms, or conditions that occur in the abdominal area. organs in the thoracic cavity and assessing the severity of the hernia.
Can PPDH be treated in cats? Yes, PPDH can be treated surgically. The procedure aims to return the organs to the abdominalThe term "abdominal" refers to anything that concerns the belly or the abdomen. It is an adjectival expression used to describe the location, symptoms, or conditions that occur in the abdominal area. cavity and close the defect in the diaphragm. The operation is usually successful, with a favorable 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. with 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.
What risks are associated with surgery to treat PPDH? As with any surgery, there are risks, including infections, bleeding, and complications from 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.. However, an experienced veterinarian will take measures to minimize these risks, and the survival rate after surgery is generally high.
Can cats with PPDH live a normal life? With timely 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 successful surgical treatment, most cats with PPDH can lead a normal and healthy life. Regular veterinary check-ups are important to ensure the cat’s long-term health.
Are there preventive measures against PPDH? Since PPDH can have a genetic component, it is important to promote responsible breeding practices and not to use cats with known genetic predispositions for breeding. Genetic testing can help identify risks.
What should cat owners do if they suspect their cat has PPDH? If you suspect your cat has PPDH, you should consult a veterinarian immediately. 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 for 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.. The veterinarian will perform the necessary tests 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..
Are certain cat breeds more susceptible to PPDH? Yes, certain cat breeds such as Maine Coon, Persian cats, and Himalayan cats appear to be more susceptible to PPDH. It is believed that genetic factors may play a role in these breeds. Breeders and owners should be aware of these risks.

Frequently asked questions (FAQs)

1. What is a Peritoneopericardial Diaphragmatic Hernia (PPDH) in cats?

A PPDH is a congenital malformation in which there is a defect in the diaphragm that leads to a direct connection between the abdominal cavity and the pericardial sac. This can cause abdominal organs to enter the chest cavity.

2. How common is PPDH in cats?

PPDH is a relatively rare condition in cats. The exact frequency is not known, but it is believed to be more common in certain breeds such as Maine Coon and Persian cats.

3. What symptoms occur in cats with PPDH?

The symptoms can vary, but often include vomiting, cough, loss of appetite, vomiting, weight loss, and lethargy. However, some cats show no symptoms until the condition is discovered incidentally during a routine examination.

4. How is PPDH diagnosed?

PPDH is usually diagnosed through imaging techniques such as X-ray, ultrasound, or MRI. These techniques allow for visualizing the position of abdominal organs in the thoracic cavity and assessing the severity of the hernia.

5. Can PPDH be treated in cats?

Yes, PPDH can be treated surgically. The procedure aims to return the organs to the abdominal cavity and close the defect in the diaphragm. The operation is usually successful, with a favorable prognosis with early diagnosis and treatment.

6. What risks are associated with surgery to treat PPDH?

As with any surgery, there are risks, including infections, bleeding, and complications from anesthesia. However, an experienced veterinarian will take measures to minimize these risks, and the survival rate after surgery is generally high.

7. Can cats with PPDH live a normal life?

With timely diagnosis and successful surgical treatment, most cats with PPDH can lead a normal and healthy life. Regular veterinary check-ups are important to ensure the cat's long-term health.

8. Are there preventive measures against PPDH?

Since PPDH can have a genetic component, it is important to promote responsible breeding practices and not to use cats with known genetic predispositions for breeding. Genetic testing can help identify risks.

9. What should cat owners do if they suspect their cat has PPDH?

If you suspect your cat has PPDH, you should consult a veterinarian immediately. Early diagnosis and treatment are crucial for a good prognosis. The veterinarian will perform the necessary tests to confirm the diagnosis.

10. Are certain cat breeds more susceptible to PPDH?

Yes, certain cat breeds such as Maine Coon, Persian cats, and Himalayan cats appear to be more susceptible to PPDH. It is believed that genetic factors may play a role in these breeds. Breeders and owners should be aware of these risks.