Heart Defect (Congenital) in Cats

Congenital heart defects are found in various forms, including patent ductus arteriosus, ventricular septal defect, mitral valve dysplasia, endocardial fibroelastosis and aortic stenosis. The good news is, heart defects are rarely found in cats. However, cats with a heart defect should be treated as soon as possible.

Congenital heart defects are present from birth, rather than developed later in life. Cats are usually diagnosed with the defect when they are middle-aged or older, though they have been suffering from the condition since birth. The heart defects are usually a result of genetics, environment or secondary conditions.

The symptoms vary per defect, but a cat suffering from a congenital heart defect may display the following symptoms:

• Coughing
• Vomiting
• Weight loss
• Difficulty breathing
• Fatigue or weakness
• Exercise intolerance
• Irregular heartbeat
• Heart murmurs
• Stunted growth
• Bluish tint of skin
• Bluish tint of membranes
• Seizures
• Collapse

It is important to take your cat to the veterinarian as soon as you notice the symptoms of a heart defect. The condition can lead to problems such as right-to-left shunting and congestive heart failure.

Types

The following conditions are known as congenital heart defects:

• Aortic stenosis: A block of the aorta that affects the blood flow.
• Atrial and ventricular septal defects: The septum reopens and causes right-to-left shunting to continue.
• Cor triatriatum sinister: A fibrous membrane divides the left atrium.
• Endocardial fibroelastosis: The left ventricle wall becomes enlarged and thickens the membrane around the heart.
• Mitral and triscuspid valve dysplasia: The mitral heart valve is not developing or functioning properly.
• Patent ductus arteriosus: The ductus arteriosus does not close so the blood can flow to the lungs.
• Pulmonic stenosis: Blocks the blood from flowing to the right ventricle.
• Tetralogy of Fallot: Lack of oxygen in the blood.
• Ventricular septal defects: The membranes that separate the ventricles are open.

There are various causes involving the mother that can lead to congenital heart defects in your cat. The causes of congenital heart defects include:

• Genetics
• Medications
• Infections
• Poisoning
• Environment
• Poor nutrition

It is vital to take your cat to the veterinarian before the condition progresses to heart failure. Expect to answer questions about the medical history of your cat and its mother. Your veterinarian will give your cat a complete physical examination to check their heart, lungs, abdomen and overall health. A stethoscope examination allows your veterinarian to check for heart murmurs. Heart murmurs can be related to other conditions, so you may have to take your cat to a veterinary cardiologist for an accurate diagnosis.

Your cat may need to undergo additional tests so your veterinarian can check the severity of the condition. A chest x-ray will show fluid in the lungs and other problems with the heart. Your veterinarian may order an echocardiogram so they can make sure the heart is working properly. There is a chance your cat may need to undergo a cardiac ultrasound with the echocardiogram. Your veterinarian may also order an electrocardiography to measure the electrical activity of the heart.

Treatment options depend on the heart defect, and can range from medication to surgery. Expect your cat to stay in the hospital for several days for monitoring and care as it recovers from the procedure.

Treating Symptoms

Symptoms, such as coughing and rapid breathing, will be treated before the actual heart defect is treated. The treatment may include oxygen therapy and administering nitrates.

Medication

Your veterinarian may prescribe medication to relieve symptoms and reduce the signs of heart failure.

Surgical Procedures

Your veterinarian may recommend a surgical procedure to treat the heart defect, ranging from tying the artery to closing the ductus arteriosus.

Other Procedures

There are other specialized procedures that are used to treat heart defects. Cats with patent ductus arteriosus may undergo catheterization to close the vessel. A cat suffering from mitral and tricuspid valve dysplasia may need to have the fluid drained from their abdomen periodically.

Your veterinarian will give you instructions for taking care of your cat and keeping any incision area clean after treatment. It is important to follow these instructions to keep your cat healthy. Make sure your cat does not chew or bite on any bandages or stitches, and contact your veterinarian immediately if they become wet or damaged.

You should schedule a follow-up appointment so your veterinarian can make sure your cat is recovering from the treatment and that prescribed medications are effective. Bandages, stitches, or sutures are usually removed within seven to ten days.

Your cat’s prognosis depends on the nature of its heart defect and the treatment method. Cats with a severe heart defect are usually given a guarded to poor prognosis. Minor defects with successful treatment can result in a full recovery.