Congenital Heart Defects in Cats

Feline congenital heart defects are not often diagnosed until later in life. However, kittens can show symptoms shortly after birth although it is rare. Congenital heart defects are problems within the structure of the heart that develop while the cat is still in the womb.

Cats can have heart problems that are not due to infection, disease or trauma. Some cats are born with heart issues that can cause them to have poor health. 

Congenital heart defects in felines are often characterized by specific symptoms. Below are some of the most common symptoms affecting domestic cats.

• Chronic coughing
• Distended abdomen
• Fluid build-up in the stomach
• Bluish-tinted skin
• Inability to exert themselves during exercise
• Losing consciousness
• Labored breathing

Types

There are several types of congenital heart defects seen in cats. It is often difficult to diagnose them because they present a similar set of symptoms. Here are some types of heart defects that can be present at birth:

• Aortic stenosis
• Pulmonary valve stenosis
• Atrial Septal Defect
• Patent Ductus Arteriosus
• Tetralogy of Fallot
• Mitral and Tricuspid Valve Dysplasia
• Cor Triatriatum Sinister
• Endocardial Fibroelastosis

Congenital heart defects in cats occur in the womb. These conditions are considered rare. According to the Merck Manual Pet Health Addition, congenital heart defects are seen in less than 1 percent of the feline population. While in many cases there are no known causes, there are some things that are believed to cause these defects to occur. Some of these causes are:

• Genetics
• Chemical ingestion or poisoning in the mother
• Malnutrition of the mother
• Medications taken by the mother during pregnancy

Veterinarians use a variety of methods to diagnose a congenital heart defect in cats. Your doctor will take a detailed medical history from you before examining your cat. In order for him to have an accurate picture you should include any information you have regarding the pregnancy of the mother, birth history and any symptoms you have seen in your cat for the last several months. It is important to include the date of onset as well. After taking a medical history, your veterinarian will perform an examination. He will observe your cat’s gait, motor skills and overall behavior.

Certain laboratory tests will help your doctor obtain an accurate diagnosis. The technician will take a blood sample from your cat and send it away for testing. A CBC, or complete blood count, will detect infection and your doctor may also look for signs of thyroid or diabetic conditions. A urine sample will also be taken to look for signs of infection. 

Diagnostic tests such as X-rays are performed to detect structural defects in the heart. These are usually done in-house. Advanced tests may require a referral to a specialty veterinary clinic. An electrocardiogram is often used to view defects in the vessels of the heart. An echocardiogram may give information such as dilation of heart ventricles. CT scans can give veterinarians a more detailed view than X-rays of the heart and lungs. This test can be performed with contrast dye to provide even more information. An MRI can also give veterinarians more information regarding the structure of the heart, valves, and ventricles than other imaging tests. 

The treatment of congenital heart defects in cats depends on the cause of the condition. Mild symptoms may require no treatment at all. Kittens may have a mild heart murmur that is known as an innocent murmur in the veterinary world. This means that while the doctor can detect a murmur, it will not affect the health of the cat at present or in the future. In older cats, the treatment may consist of keeping the cat as comfortable as possible with lifestyle changes, special diets and medications. Surgery to correct structural defects of the heart is not often recommended for cats over 10 years of age. 

In young cats or kittens, doctors may recommend surgery to repair congenital defects that cause structural abnormalities. Some of types of surgeries performed on cats include cardiopulmonary bypass, surgery to repair chambers of the heart, and aortic repair. 

In younger cats, medications such as diuretics, digoxin and vasodilators may be prescribed to help control symptoms. Some conditions such as mitral valve problems are not well controlled with medications.

The recovery period of congenital heart defects in cats is dependent upon the diagnosis and treatment plan. Not all congenital heart defects in felines are severe enough to require surgery. Some can be managed with attention to exercise restriction and medications. In cats that require surgery, the recovery period varies according to the type of surgery performed and the age of the cat. No matter what the diagnosis or treatment, the recovery and overall health of the cat is best accomplished by adhering to the advice of your veterinarian.