Physiologic Murmur in Cats

Physiologic Murmur in Cats

A physiologic murmur is quite common in cats.  

This is usually the result of a dynamic right ventricular outflow tract obstruction (dRVO).  

This condition is created when the muscle of the right ventricular outflow tract squeezes and narrows the exit to the right ventricle.  

Much like a garden hose with your thumb over the end, this creates fast and turbulent blood flow, which is noted as a murmur.  

This finding has been well-studied in cats and is not linked to any advserse clinical outcomes, concerns, or problems.  

The primary worry is that it limits our accuracy of auscultation in monitoring for adult-onset disease. 

No treatments or medications are required.

Pulmonary Arterial Hypertension in Cats

Pulmonary Arterial Hypertension in Cats

Pulmonary arterial hypertension is a state of high blood pressure within the lung (pulmonary) circulation.  

This condition can be due to heartworm disease and embolic disease (clots into the lungs); however, some cases are considered idiopathic (cause unknown).  

Many cases may also develop pulmonary arterial hypertension due to chronic airway disease (pulmonary fibrosis, cancer, or pneumonia).  

This disease process involves damage to the pulmonary arteries and thickening/constriction of these vessels, increasing resistance to flow.  

Medications are utilized to reduce the pulmonary arterial pressures and improve quality of life.  

No medications can return these pressures to normal; however, many patients display a significant improvement in their quality of life.

Systemic Hypertension in Cats

Systemic Hypertension in Cats

Systemic Hypertension is a state of high blood pressure within the body.  

This means that the heart must work very hard to propel blood forward, which increases oxygen demands and can cause changes to the myocytes (muscle cells).  

In veterinary medicine, this condition is typically a result of chronic kidney disease, thyroid disease, or various other metabolic conditions.  

In some cases, essential (idiopathic) hypertension may be suspected.  This condition can cause severe end-organ damage to include the brain, heart, kidneys, and eyes.

If an underlying condition can be identified, treatment is directed towards that condition and maintaining the systemic blood pressure at a reasonable level with medications.

 Frequent rechecks are required to optimize the dose of anti-hypertensive medications

Feline Aortic Thromboembolism

Feline Aortic Thromboembolism

An aortic thromboembolism is a blood clot that has developed within the heart.  

It typically lodges at the distal aorta, often termed a “saddle thrombus”, which supplies the rear limbs with blood.  

This condition makes the affected limbs painful, cold to touch, and typically non-functional.  

Approximately 50% of patients with this condition are also in at least mild congestive heart failure at the time the clot is noted.

Plavix has been recently shown by the FAT CAT study to be the most effective antiplatelet medication in our feline friends.  

Urgent medical attention is necessary if these signs are noted or return.

Please use caution when handling a patient that you believe may have developed a thrombus.

These animals are typically in severe pain and may scratch or bite.  

Also, they likely cannot handle a high degree of stress due to their fragile status.  Be gentle, place the patient into a carrier, and contact a 

veterinarian as soon as possible.

Restrictive Cardiomyopathy in Cats

Restrictive Cardiomyopathy in Cats

Restrictive Cardiomyopathy is a primary myocardial disease wherein the heart muscle is damaged.

The myocardium becomes infiltrated with fibrous scar tissue that prevents normal function (failure of both squeezing and relaxation).  

This is a non-curable and progressive disease.  As the ventricle does not relax normally, the left atrium dilates as it is unable to push the blood into the small left 

ventricular chamber.  This eventually can lead to the development of congestive heart failure (fluid in the lungs), which is a medical emergency that makes breathing very difficult.  This disease is typically progressive; however, the rate of progression is highly variable.  Recheck echocardiograms are necessary to monitor the rate of change, chamber sizes, and determine if any additional medications or adjustments are indicated.

Once the left atrium has dilated, affected patients are at an increased risk for thromboembolic disease.  

This is when a blood clot forms within the left atrium or auricle, which can dislodge and go to various points within the body.  

The most common location is the distal aorta (often termed a “saddle thrombus”), which supplies the rear limbs with blood.  When this happens, affected patients are very painful, the limbs cool to touch, and the legs are typically non-functional.  

The right front leg is the second most common location.  Any other clinical signs are determined by the site of the clot lodging.  

This could include sudden death if the brain were to be affected by this.  Anti-platelet medications are utilized to minimize the chances of this developing; however, no medications are 100% effective in preventing this condition.  

Plavix has been recently shown by the FAT CAT study to be the most effective antiplatelet medication in our feline friends.  

If you notice any clinical signs or leg weakness, consider it a medical emergency.

Hypertrophic Cardiomyopathy in Cats

Hypertrophic Cardiomyopathy in Cats

Hypertrophic Cardiomyopathy is a primary myocardial disease wherein the heart muscle is damaged.

The myocytes (muscle cells) become markedly thickened and replicate in a non-uniform pattern.

This causes the ventricle (pumping chamber) to become severely thickened, which reduces the chamber size for blood.  

This disease is characterized by a diastolic (filling) failure.  

This causes the left atrium to dilate as it is unable to push the blood into the small left ventricular chamber.  

This eventually can lead to the development of congestive heart failure (fluid in the lungs), which is a medical emergency that makes breathing very difficult.  

This disease is typically progressive; however, the rate of progression is highly variable.  

Recheck echocardiograms are necessary to monitor the rate of change, chamber sizes, and determine if any medications or adjustments are indicated.

Once the left atrium has dilated, affected patients are at an increased risk for thromboembolic disease.  

This is when a blood clot forms within the left atrium or auricle, which can dislodge and go to various points within the body.  

The most common location is the distal aorta (often termed a “saddle thrombus”), which supplies the rear limbs with blood.  

When this happens, affected patients are very painful, the limbs cool to touch, and the legs are typically non-functional.  

The right front leg is the second most common location.  Any other clinical signs are determined by the site of the clot lodging.  This could include sudden death if the brain were to be affected by this.  

Anti-platelet medications are utilized to minimize the chances of this developing; however, no medications are 100% effective in preventing this condition.

Plavix has been recently shown by the FAT CAT study to be the most effective antiplatelet medication in our feline friends.  

If you notice any clinical signs or leg weakness, consider it a medical emergency.

Dilated Cardiomyopathy in Cats

Dilated Cardiomyopathy in Cats

Dilated Cardiomyopathy is a primary myocardial disease wherein the heart muscle is damaged and becomes very weak.  

In cats, this is usually idiopathic, but can develop secondary to nutritional deficiencies (specifically Taurine deficiency).  

The left ventricle dilates and has a marked systolic dysfunction (pump dysfunction).  

This causes an elevation in left ventricular and left atrial pressures as the poorly pumping chamber continues to dilate.  

Eventually, this results in dilation of the left atrium and fluid accumulation within the lungs (congestive heart failure).  

This makes breathing difficult and requires urgent medical attention.

Unfortunately, there is likely no cure for this disease (unless Taurine deficiency is the underlying etiology).  

Ongoing rechecks and medical management are utilized to maximize the quality of life for affected patients.  The disease progression is variable, with some patients doing well for years and others progressing into congestive heart failure rapidly.  

This disease is also frequently associated with the development of arrhythmias (abnormal electrical beats) that can predispose affected patients to sudden death.  

Additional diagnostics, such as 24 hour Holter Monitors, may be recommended based on our initial findings.  

If any clinical signs of arrhythmias such as a “dazed” appearance or collapse are noted, please contact your trusted veterinarian or your local emergency clinic immediately.