Congestive Heart Failure in Cats

Congestive heart failure (CHF) is a life-threatening condition caused by a variety of underlying diseases. Some causes are common in cats (hypertrophic cardiomyopathy) compared to others, however, CHF is more common overall in dogs than in cats. Left-sided heart failure is more common than right-sided heart failure in cats.

There is no cure for CHF. It is important to note that CHF is a progressive condition, which must be closely monitored. Regular check-ups with a veterinarian are crucial to monitor the condition, and to adjust treatments as necessary.

Exercise and high altitudes may exacerbate symptoms of CHF. Cats with CHF are at greater risk of complications or death when under anesthesia.

Cats experiencing loss of consciousness or collapse require emergency care. Cats showing any symptoms of heart failure or CHF should be urgently assessed by a veterinarian.

Some causes of CHF have a genetic component and some breeds may be prone to developing cardiomyopathies and CHF, such as Maine Coons or ragdolls. Male cats are predisposed to hypertrophic cardiomyopathy (HCM) and restrictive cardiomyopathy which can lead to CHF. Obese cats have a greater risk of developing heart disease and subsequent CHF.

CHF associated with congenital defects usually develops in young cats. Cardiomyopathies are more likely to develop in middle-aged cats.

CHF symptoms can vary depending on which side of the heart is failing. For example, left- sided heart failure results in fluid retention in the lungs, which leads to breathing difficulties. Right side heart failure (less common) results in fluid retention in the abdomen and, less commonly, the lower extremities.

In cases with reduced blood output by the heart, lower body temperature and cold extremities may result.

CHF may cause collapse or loss of consciousness if heart and lung function are not sufficient to maintain blood flow and oxygen levels.

Cats with heart disease and CHF may develop blood clots. Signs include acute pain in the limbs, limping, and loss of leg function.

Other conditions may be mistaken for CHF based on symptoms (pulmonary edema). Ascites (fluid in the abdomen) can occur in CHF and may appear similar to pregnancy.

Congestive heart failure (CHF) is a syndrome caused by the abnormal accumulation of fluid in the lungs or other tissues. Fluid accumulation occurs when the right, left, or both sides of the heart are not pumping blood effectively.

Diagnosis includes:

• Physical examination
• Blood pressure monitoring
• Blood analysis
• X-rays
• Echocardiogram (ultrasound of the heart)
• Electrocardiogram (ECG)

Treatment of CHF includes medication to manage fluid accumulation, heart function, and reduce symptoms.

Acute breathing difficulties may be treated with oxygen therapy.

When fluid buildup is severe, a veterinarian may drain the fluid from the chest or abdominal cavity (thoracentesis, abdominocentesis).

Monitoring the resting or sleeping breathing rate of cats over time is often done throughout treatment and is important to gauge the effectiveness of medication and adjust dosage. Increased breathing rate may indicate a worsening condition requiring reassessment.

Depending on the underlying cause, CHF can be managed well by medications and cats with CHF can have a good quality of life.

CHF is a chronic condition which cannot be cured. Medication can control the symptoms of CHF, but inevitably the underlying heart disease progresses and medication loses efficacy.

Maintaining a healthy diet and weight may help prevent CHF.

CHF is not contagious. Heartworm is an infectious cause of CHF, however it is not directly contagious between cats; it is transmitted by mosquito bites. Heartworm may be prevented by keeping cats indoors, and by preventive medication.

CHF is less common in cats than in dogs, however underlying conditions that can result in CHF, such as hypertrophic cardiomyopathy, are more common.

• Diuretics
• Blood pressure medication (e.g. ACE inhibitors)
• Medication to regulate the heartbeat or heart function (e.g. Beta-blockers, digoxin, pimobendan)
• Medication to ease blood flow (vasodilators)
• Oxygen therapy
• Draining fluid (thoracentesis, pericardiocentesis, abdominocentesis)
• Low-sodium diet