Pectus Excavatum in Cats

Pectus excavatum is a congenital chest wall deformity sometimes called funnel chest. In affected cats, the sternum and nearby rib cartilages develop abnormally, creating a visible or palpable inward dip along the chest. That change can reduce space inside the chest and may push the heart leftward or compress parts of the lungs. Some kittens have only a mild shape change, while others develop meaningful breathing or heart-related problems early in life.

This condition is uncommon in cats, but it matters because severity can vary a lot. A kitten with a mild deformity may act normal and only need monitoring. A kitten with a deeper chest depression may breathe faster, tire easily, grow poorly, or show signs of low oxygen. Symptoms may become more noticeable as the kitten grows, especially if the chest becomes less flexible over time.

Pectus excavatum is present from birth, although it is not always recognized right away. Burmese and Bengal cats have been reported as predisposed, which suggests a hereditary component in at least some lines. Because the deformity can affect both breathing and circulation, your vet may recommend anything from watchful monitoring to referral surgery, depending on how your cat looks, feels, and functions.

Diagnosis starts with a hands-on exam. Your vet will look at your cat’s breathing pattern, growth, gum color, heart and lung sounds, and the shape of the chest. In many cats, the chest depression can be felt during palpation. That physical exam helps determine urgency, but imaging is usually needed to confirm the deformity and estimate how much it is affecting the organs inside the chest.

Chest X-rays are the usual first imaging step. They help show the shape of the sternum, the degree of thoracic narrowing, and whether the heart appears displaced. In more complex cases, your vet may recommend a CT scan. CT can better define the deformity and may show that organ displacement does not always match what the outside of the chest looks like. Some cats also need echocardiography if there is a murmur, concern for heart compression, or suspicion of another congenital defect.

Baseline blood work is often part of the workup before sedation, anesthesia, or surgery. If your cat is very young and symptomatic, your vet may also discuss referral to a surgical specialist or teaching hospital early in the process. That is especially common when breathing signs are present or when the chest is becoming less flexible with age.

Pectus excavatum is considered a congenital defect, meaning it develops before birth. The exact cause is not fully understood. The sternum and associated costal cartilages do not form in the usual way, leading to a dorsal deviation of the caudal sternum and a narrowed, flattened chest. Because the condition has been reported more often in certain breeds, genetics are strongly suspected to play a role in at least some cats.

Burmese and Bengal cats are the most commonly cited predisposed breeds in veterinary references. That does not mean other cats are protected. Mixed-breed cats and cats without a known family history can still be affected. The condition may appear alone or alongside other congenital abnormalities, which is one reason your vet may recommend a broader workup in some kittens.

Pet parents do not cause pectus excavatum through routine care, feeding, or handling. There is no evidence that normal activity after birth creates the deformity. If a hereditary component is suspected, breeding affected cats or close relatives is generally avoided. Your vet can help you decide whether screening littermates or related cats makes sense in your situation.

Because pectus excavatum is congenital, there is no reliable way to prevent it once a kitten is developing in the womb. Good prenatal care and normal kitten care are still important for overall health, but they do not guarantee prevention of this specific chest wall defect. The most practical prevention strategy is early recognition and thoughtful breeding decisions when a hereditary pattern is suspected.

If a breeder, rescue, or pet parent notices a kitten with a sunken chest, fast breathing, or poor growth, early veterinary evaluation matters. Young kittens have more flexible cartilage and bone, so timing can affect which treatment options are realistic. Catching the problem early may allow less invasive correction in some cases and can reduce the risk of waiting until the chest becomes more rigid.

For cats known to be affected, breeding is usually discouraged. If related cats are being considered for breeding, your vet may advise careful physical screening and review of family history. Prevention in practice often means reducing recurrence in breeding lines and identifying affected kittens before symptoms become severe.

Prognosis depends mainly on severity, age at treatment, and whether the heart and lungs are being compressed. Mild cases can do well with monitoring alone and may live comfortably without surgery. Cats with moderate to severe disease have a more guarded outlook if breathing or cardiovascular signs are already present, but many improve when the deformity is corrected appropriately.

Recovery varies by treatment type. External splints are often worn for four to eight weeks, with regular rechecks and repeat X-rays to confirm the sternum is moving into a safer position. Internal surgical repair usually involves a longer and more intensive recovery, including hospitalization, pain control, and monitoring for complications such as pneumothorax or implant-related issues. A recent JAVMA study of internal plate fixation in six cats and one dog reported successful recovery in all animals, with improved chest and lung volumes and relatively few complications.

Even after successful correction, follow-up matters. Your vet may recommend repeat imaging, breathing assessments, and activity guidance during healing. Cats that were severely affected early in life may still need long-term monitoring, especially if they had lung changes or other congenital problems. The outlook is often best when the condition is recognized early and treatment is matched to the cat in front of you.