Heart Murmur During Heart Contraction in cats

Author: Dr. med. vet. Gisa Löwe | Last modified: 17.02.2026
Table of contents

When to visit the vet?

Non-urgent see a veterinarian within 2–3 days

?

ORANGE if there is an additional gallop rhythm, significantly increased respiratory rate/increased respiratory effort, weakness, fainting/syncope, pale mucous membranes, or if the murmur is new and loud. RED for respiratory distress (mouth breathing, dyspnea), collapse, or cyanosis.

Unsure about what’s wrong with your pet? Feel free to use our Symptom Checker for more clarity

Definition

A heart murmur during heart contraction in cats is an abnormal sound heard during auscultation of the heart with a stethoscope. It occurs when the heart pumps blood and can indicate various heart diseases or other health problems.

Can Occur with the Following Diseases:

Basics and possible causes

Heart murmurs are caused by turbulent blood flow in the heart or adjacent large blood vessels. These turbulences can be caused by structural anomalies, such as heart valve defects or defects in the cardiac septa. In cats, it is not uncommon for heart murmurs to be detected, but they are not always pathological.

Among the most common causes of heart murmurs in cats is hypertrophic cardiomyopathy (HCM), a condition in which the heart wall is thickened, which can impair the normal function of the heart. This thickening can lead to increased turbulence of blood flow, which causes the murmur.

Other possible causes include congenital heart defects, such as a patent ductus arteriosus or a ventricular septal defect. Acquired heart problems, such as heart valve insufficiency or endocarditis, can also cause heart murmurs. In addition, systemic diseases, such as hyperthyroidism or anemia, can secondarily lead to heart murmurs by altering blood flow or cardiac load.

Typical accompanying symptoms

  • Respiratory distress: Cats with heart problems may show shortness of breath or an increased respiratory rate. These symptoms occur because the heart does not pump blood effectively enough, leading to fluid accumulation in the lungs.

  • Lethargy: Reduced activity or unusual lethargy may indicate that the heart is unable to distribute enough oxygen in the body.

  • Loss of appetite: A decreased interest in food can be a non-specific sign associated with heart disease, as the body conserves energy and focuses on vital functions.

  • Cough: A less common symptom in cats than in dogs, but it can occur, especially if fluid gets into the lungs.

  • Fainting spells: If heart function is severely impaired, sudden fainting or fainting spells may occur.

  • Bluish mucous membranes: Cyanosis, a bluish discoloration of the mucous membranes, can occur if the oxygen content in the blood is too low.

When to see a vet?

A veterinary visit is essential if one or more of the above symptoms occur in the cat. In particular, respiratory distress, fainting spells, and bluish mucous membranes are signs of serious problems and require immediate attention.

Even if no symptoms are visible, a heart murmur detected during a routine examination should be further investigated by a veterinarian. This is important to determine whether the sound is harmless or if there is an underlying heart condition that needs to be treated.

Early diagnosis and treatment can slow the progression of heart disease and significantly improve the cat’s quality of life.

Symptom recognition for the pet owner and veterinary diagnostic procedure

For pet owners, it is often difficult to detect heart murmurs themselves, as they can only be heard with a stethoscope. However, pay attention to the accompanying symptoms described. If you notice any abnormalities, it is important to inform the veterinarian.

The veterinarian will first perform a thorough clinical examination and auscultate the heart with a stethoscope. During this, heart murmurs can be detected and their intensity and character assessed.

For further diagnosis, imaging techniques such as ultrasound (echocardiography) can be used to examine the structure and function of the heart more precisely. Chest X-rays can also be helpful to assess the size and shape of the heart, as well as possible fluid accumulation in the lungs.

Additional tests, such as blood tests to check thyroid hormones or changes in blood count, may be performed to rule out systemic causes for the heart murmur.

What the pet owner can do and professional therapy options

If a heart murmur has been detected, the pet owner should follow the veterinarian’s recommendations precisely to optimize the cat’s health. This may mean administering medication to support heart function or making specific dietary adjustments to reduce the strain on the heart.

Be sure to minimize stress for the cat, as this can increase cardiac load. A calm environment and gentle, regular activity can help support heart health.

It is important to schedule regular follow-up appointments with the veterinarian to monitor progress and adjust treatment if necessary. Early interventions and continuous care can significantly improve the quality of life and life expectancy of cats with heart problems.

Outlook on current research

Recent research in cardiology in cats focuses on understanding the mechanisms that cause heart murmurs during heart contraction. It is known that heart murmurs arise from turbulent blood flows that can be caused by structural or functional anomalies in the heart. Researchers are working to analyze the precise acoustic properties of these sounds to develop better diagnostic tools. Modern technologies such as Doppler ultrasound and 3D cardiac imaging play a crucial role in visualizing these flows and determining their causes.

Another focus of research is on genetic factors that can lead to heart murmurs in cats. By studying genetic variations in different cat breeds, researchers hope to identify predisposing genetic markers associated with the development of heart murmurs. These findings could help develop breeding measures that reduce the risk of heart problems in future generations.

In addition, research is being conducted on the development of non-invasive diagnosis methods that allow early detection and monitoring of heart murmurs. New biometric monitoring technologies that continuously record cardiac parameters in cats could help detect subtle changes in heart rhythm or sound in the future, before they become clinically significant. Such technologies could also facilitate long-term monitoring of cats with already diagnosed heart murmurs.

Another exciting development is the research into the effects of environmental factors on the heart health of cats. Studies investigate the extent to which diet, stress, and lifestyle influence the occurrence and severity of heart murmurs. By combining these environmental factors with genetic data, researchers hope to develop personalized prevention strategies tailored to the individual needs of each cat.

Finally, therapeutic approaches are also being further developed to improve the management of heart murmurs in cats. This includes the investigation of new medications that can support or improve heart function, as well as alternative therapies such as acupuncture and special diets. The integration of traditional and modern medical approaches could significantly improve the quality of life for cats with heart murmurs.

Frequently asked questions

1. What is a heart murmur in cats?
A heart murmur in cats is an additional, unusual sound that occurs during heart contraction and is detectable with a stethoscope. It is caused by turbulent blood flow in the heart.
2. Is every heart murmur in cats a cause for concern?
Not all heart murmurs are clinically significant. Some may be harmless, while others may indicate serious heart problems. A thorough veterinary examination is important to determine the cause.
3. How is a heart murmur diagnosed in cats?
A heart murmur is usually detected during a physical examination by auscultation with a stethoscope. Further tests such as ultrasound or X-rays may be necessary to determine the cause.
4. Can heart murmurs in cats disappear on their own?
In young cats, some heart murmurs may disappear on their own, while others may persist or worsen. Regular check-ups by the veterinarian are important to monitor changes.
5. What symptoms can occur in addition to a heart murmur?
Accompanying symptoms can include respiratory distress, lethargy, cough, or decreased activity. These symptoms should be taken seriously and checked by a veterinarian.
6. Are there certain cat breeds that are more susceptible to heart murmurs?
Yes, some breeds such as Maine Coon, Persian, and British Shorthair are genetically more susceptible to heart problems that can lead to murmurs.
7. How is a heart murmur treated in cats?
The treatment depends on the underlying cause. In some cases, medication is required, while other cats may not need specific treatment, but only regular check-ups.
8. Can heart murmurs be influenced by diet?
Yes, a balanced diet can influence heart health. Special diets or supplements may be part of a treatment plan aimed at heart health.
9. Are heart murmurs more common in older cats?
Heart murmurs can occur in both young and older cats, but the likelihood increases with age due to age-related changes in the cardiovascular system.
10. How often should cats with heart murmurs be examined by a veterinarian?
Cats with diagnosed heart murmurs should be examined regularly by a veterinarian, at least every 6 to 12 months, to monitor the condition and adjust treatment if necessary.