British fold cats hypertrophic cardiomyopathy. Symptoms of cardiomyopathy in cats. How the disease develops

Myocardial disease is the most common acquired disease in cats. They can be divided into several types of cardiac diseases.

Primary myocardial diseases: hypertrophic cardiomyopathy, dilated cardiomyopathy, restrictive cardiomyopathy, unclassified cardiomyopathy, arrhythmogenic cardiomyopathy.
Secondary myocardial diseases occur with hypertension, hyperthyroidism, taurine deficiency (occurs when fed with natural feed).

Primary myocardial diseases differ from secondary ones in that they do not have the causes that cause these diseases.

Cardiomyopathies are most common in Persian, Scottish Fold, British and similar breeds, in Maine Coons, Siamese, Abyssinian, but can also develop in cats of any breed. Clinical signs are usually seen in predisposed cats around 5 years of age, the rest over 10 years of age. Cats are much more likely to get sick than cats, and symptoms may appear as early as 1 year of age.

Clinical manifestations are shortness of breath, intolerance to physical activity (fatigue), breathing open mouth during emotional or physical stress. AT advanced cases failure of one or two hind limbs with a decrease in paw temperature.

But the disease can also be asymptomatic, until a heart murmur is detected during a routine examination. As a rule, cats come to the clinic in the stage of decompensation, as the owners do not notice the gradually increasing intolerance to physical activity.

Hypertrophic cardiomyopathy characterized by compensatory hypertrophy of the ventricular myocardium without any obvious cause.
Dilated cardiomyopathy characterized by left ventricular enlargement and diastolic dysfunction. At the same time, the internal diameter of the left ventricle increases and myocardial contractility is reduced.
Restrictive cardiomyopathy is characterized by neither expansion nor hypertrophy of the left ventricle, however, it is accompanied by a violation of the filling of the left ventricle, which leads to the expansion of the left atrium.
Unclassifiable or intermediate cardiomyopathy This term is sometimes used to describe patients with multiple disorders, such as hypertrophy and diastolic dysfunction.

Arrhythmogenic cardiomyopathy of the right ventricle characterized by a marked expansion and thinning of the walls of the right ventricle, many of them have arrhythmia.

For the diagnosis and differentiation of diseases, instrumental methods such as radiography are used. chest so that you can visually determine the size of the heart shape; echocardiography (ultrasound of the heart) to determine the structure of the heart and its functional state; electrocardiography when the doctor listens to an uneven rhythm.

Forecast

The main determining factors in cats are the presence or absence of clinical signs, the presence or absence of expansion of the left atrium. Decompensated cats arriving at the reception are at risk of death in the near future.

Cardiomyopathy in cats.

Sourced from www.icatcare.org

Additional Information:

Cardiomyopathy refers to any disease that affects the heart muscle itself. Cardiomyopathy is the most common disease and cause of heart failure in cats. Diseases of the heart valve that affect normal work hearts, which are common in humans and dogs, are quite rare in cats.

Cardiomyopathies are distinguished by the effect that the disease has on the structure and function of the heart muscle in cats:

Hypertrophic cardiomyopathy(Hypertrophic cardiomyopathy, HCM). The most common form of heart disease in cats. It is characterized by an increase in the thickness (hypertrophy) of the wall of the ventricle of the heart. This reduces the volume of blood in the heart and prevents the heart muscle from relaxing properly between contractions.
Dilated cardiomyopathy(Dilated cardiomyopathy, DCM). It is characterized by stretching (dilatation) of the walls of the cavities of the heart, due to which the cat's heart enlarges and cannot contract effectively.
Restrictive cardiomyopathy(Restrictive cardiomyopathy, RCM). It is characterized by a pronounced decrease in the extensibility of the heart muscle, an increase in its rigidity and a decrease in elasticity, which prevents the heart chambers from filling normally.
Intermediate cardiomyopathy(Unclassifiable, Intermediate cardiomyopathy, ICM). In this case, changes are observed that are characteristic of several types of the disease, for example, for hypertrophic and dilated.

Causes of cardiomyopathy in cats.

Although in most cases of heart disease in cats the underlying cause is unknown, sometimes a potential cause can be identified, which may require the veterinarian to perform certain tests. Possible reasons may include the following:

Secondary cardiomyopathy (caused by other diseases)
Hyperthyroidism (hyperactivity thyroid gland)
Hypertension (high blood pressure)
Acromegaly (excessive increase in hormone production)
Nutritional issues
Taurine deficiency (causes dilated cardiomyopathy)
Infiltration of the heart muscle
Lymphoma (a type of cancer)
Exposure to toxins
Some medicines may cause side effects
hereditary causes
Genetic defects characteristic of Maine Coons and other breeds of cats. that can cause cardiomyopathy

Symptoms of cardiomyopathy in cats.

In cardiomyopathy, changes in the heart (cardiac) muscle cause dysfunction of the heart. Deviations in the work of the cat's heart depend on the type of cardiomyopathy:

In hypertrophic and restrictive cardiomyopathy, the disturbances are mainly associated with difficulties in relaxing the heart muscle between contractions. Diastole is the relaxed state of the heart muscle when the heart beats in the interval between contractions, it is not fully achieved, so the heart cannot effectively fill with blood. AT severe cases this results in a disorder of the cat's heart known as diastolic heart failure .

Dilated cardiomyopathy primarily affects the ability of the cat's heart to contract (systole), reducing its ability to pump blood. In severe cases, this leads to disorders called systolic heart failure .

Early signs of heart disease in cats.

In the initial phase of the disease, cats may show no signs and appear completely normal. In fact, many cats with cardiomyopathy may never show clinical signs. However, while in some cats the underlying disease develops slowly, in others the disease can progress very quickly.

Some early signs Heart disease can be detected during veterinary examinations of a cat before any overt symptoms begin. This is one of the reasons why it is recommended to examine the cat annually (and older cats more often). Among warning signs the following can be named:

The presence of heart murmurs. Abnormal murmurs can be detected by a veterinarian by listening to the cat's heart through a stethoscope. The murmurs originate from areas of turbulence in the flow of blood through the heart.
gallop rhythm. Normally, each heartbeat is accompanied by two sounds, distinguishable through a stethoscope - with contraction and relaxation of the walls of the heart. With heart disease, a third sound, which is called the "gallop rhythm", can also be heard.
Deviations in the frequency of contractions. In some cases, heart disease in cats is accompanied by a significant increase or decrease in the frequency of contractions, while the heartbeat does not lead to the formation of a normal blood flow (the heart beats, but the pulse in the arteries is not palpable).
Violations heart rate (cardiac arrhythmia). Normally, cats have a very uniform pulse, but with heart disease, interference with the passage of impulses that control heart contractions may occur, which leads to disturbances. normal rhythm hearts.

Many cats, especially in the early stages of the disease, may have abnormalities that are determined only by ultrasound examination of the heart. These cats do not show clinical signs of heart disease, although many of them may develop signs in the future.

Heart failure in cats.

If the performance of the heart is significantly impaired due to cardiomyopathy, it leads to heart failure (often called congestive heart failure), where blood flow to and from the heart is impaired.

Clinical signs of heart failure can sometimes appear suddenly, and in some cats the condition worsens very quickly. Some cats may experience fainting, but this is relatively rare. Common symptoms are marked heart rhythm disturbances (which can lead to episodes where the cat's brain suffers from a lack of oxygen due to poor blood supply).

Unlike dogs, cats are not active at the same time (for example, on a walk), so in cats, the decrease in activity often occurs imperceptibly, masking early signs of developing heart disease. The cat just gradually begins to spend more time resting and sleeping. Since cats are good at hiding diseases, and it is often difficult to detect abnormalities in the early stages (especially without special examinations), clear signs appear only after reaching the "critical point", which can lead to sudden or rapid development quite severe conditions.

The most common sign of heart failure in cats is difficulty breathing—shortness of breath and/or rapid breathing (tachypnea). It is mainly caused by either the accumulation of fluid in chest cavity around the lungs (pleural effusion) or by accumulation of fluid in the lungs themselves (pulmonary edema).

Simultaneously with difficulty in breathing, cats have cooling of the extremities (paws and ears), and pallor of the mucous membranes (gums and eyes) caused by poor circulation. Occasionally, the mucous membranes of the gums, eyes, and even the skin may experience cyanosis (cyanosis). AT rare cases cats with heart disease have a cough (although this is common in dogs).

Arterial thromboembolism in cats.

Another sign of heart disease in cats is arterial thromboembolism (Feline aortic thromboembolism, FATE). Sometimes it becomes the first indicator of developing heart disease. Thrombi (blood clots) may form in one of the heart chambers (usually the left atrium) in a cat with cardiomyopathy. This is mainly due to the fact that blood cannot pass through the heart normally. A blood clot (or clot) is first attached to the wall of the heart, but can be torn off from there and enter the blood leaving the heart. Thrombus trapped in circulatory system are called emboli (from the Greek "embolas" - plug, wedge), hence the term "thromboembolism". In the course of circulation, such emboli can get stuck in small arteries and block the blood supply to certain parts of the cat's body. Although this may occur in different parts body, most often this happens at the ends of the main arteries (aortas) emerging from the heart, where vessels are secreted from them to supply blood to the hind legs. This complication is most commonly seen in hypertrophic cardiomyopathy, and results in sudden paralysis of one or both hind legs accompanied by severe pain.

Determination of the form of cardiomyopathy in cats.

To diagnose heart disease in cats, special examinations are carried out:

Electrocardiogram(ECG). The method allows you to track electrical activity cat hearts. An ECG can be very useful in detecting abnormal heart rhythms, but has limitations in its use;
Radiography(radiography). The method allows you to identify changes in the size and shape of the cat's heart, track the accumulation of fluid (pleural effusion or pulmonary edema). With the help of radiography, you can track the results of the treatment;
Ultrasound of the heart. Ultrasounds are very useful for diagnosis, as they allow you to see a three-dimensional image of the cat's heart, determine the thickness of the walls and evaluate the contractions being made. Ultrasound helps to understand from which part of the heart the murmurs are coming. By using ultrasound examinations can quickly determine the type of heart disease in a cat. The procedure usually does not cause anxiety to the cat (it only requires a small area of hair to be shaved), so most cats undergo ultrasound without the use of sedatives and anesthetics;
Tests for detection of underlying diseases. Such examinations may be needed in some cases, usually these are blood tests, pressure measurements, etc.

Treatment of cardiomyopathy in cats.

Generally, the underlying cause of cardiomyopathy in cats is rarely treatable, but if the cardiomyopathy is secondary, due to dietary deficiency of taurine (causing dilated cardiomyopathy), or due to diseases that cause hypertension (high blood pressure), or due to hyperthyroidism (hyperactivity of the thyroid gland) - treatment of the underlying disease can positively affect the functioning of the heart.

For heart failure for cats developed various medicines to help alleviate the condition of the cat and control the disease. Among them are medicines such as:

Beta blockers(similar to atenolol or propanolol), which lower the heart rate and reduce the oxygen demand of the cat's heart.
Diltiazem a drug known as blocker calcium channels . Reduces the frequency and force of contractions of the heart. This reduces the heart's need for oxygen and helps the heart relax between contractions.
Angiotensin-converting enzyme inhibitors(for example, benazepril, ramipril, enalapril) or angiotensin receptor blockers (telmisartan). The drugs help block the activation of the renin-angiotensin-aldosterone system, a hormonal system that stimulates heart disease in cats. Their use is useful in heart failure, and also probably on early stages development of heart disease.
Pimobendan is a drug known as a calcium channel diazo sensitizer. It increases the force of contractions of the cat's heart, and also has a dilating effect on the blood vessels, which promotes blood flow. Such drugs may be used to treat cats with congestive heart failure.
Diuretics(Frusemide/Furosemide and the like) are very useful against the development of signs of congestive heart failure by helping to remove fluid that has accumulated in (or around) the lungs. The dose of drugs varies widely, depending on the result of their action.

Unfortunately, the true efficacy of many cardiac medications in cats is not clear, as there are not enough statistics on their clinical use. In addition, it should be understood that drugs act different ways, and therefore may be useful in different situations. Basically, diuretics are used to combat the signs of congestive heart failure - with early diagnosis, it is possible to slow or even stop the development of heart disease, providing the cat good quality life.

Etiology

The cause of primary or idiopathic hypertrophic cardiomyopathy (HCM) in cats is unknown, but hereditary pathology probably exists in many cases. The disease appears to be widespread in several breeds such as the Maine Coon, Persian, Ragdoll, and American Shorthair. There are also reports of HCM in littermates and other close relatives of domestic shorthair cats. Some breeds have been found to have an autosomal dominant pattern of inheritance. It is known that there are many different gene mutations in familial HCM in humans. Although some common human gene mutations do not yet appear to be found in cats with HCM, others may be found in the future. Some investigators (Meurs 2005) have also found a mutation in myocyte myosin-binding protein C in this breed. Another mutation has been found in ragdolls; testing for these mutations is currently available (www.vetmed.wsu.edu/deptsVCGL/felineTests.aspx).

In addition to mutations in genes that code for proteins responsible for myocardial contractility and regulatory proteins, possible reasons diseases include increased sensitivity of the myocardium to excess production of catecholamines; pathological hypertrophic response to myocardial ischemia, fibrosis or trophic factors; primary pathology of collagen; disturbances of the myocardial, relating to calcium, processes. Myocardial hypertrophy with foci of mineralization occurs in cats with hypertrophic feline muscular dystrophy, which is an X-linked recessive dystrophic deficiency similar to Duchenne muscular dystrophy in humans; however, congestive heart failure is uncommon in these cats. Some cats with HCM have high concentrations serum growth hormone. It is unclear whether viral myocarditis plays a role in the pathogenesis of feline cardiomyopathy. In one study, myocardial samples from cats with HCM were evaluated by polymerase chain reaction (PCR) and showed the presence of panleukopenia virus DNA in approximately one third of cats with myocarditis and did not show its presence in healthy control cats (Meurs, 2000).

Pathophysiology

Thickening of the left ventricular wall and/or interventricular septum is characteristic, but the extent and distribution of hypertrophy in cats with HCM is variable. Many cats have symmetrical hypertrophy, but some have asymmetric ventricular septal thickening and a few have hypertrophy limited to the left ventricular free wall or papillary muscles. The lumen of the left ventricle usually looks small. Focal or diffuse areas of fibrosis occur in the endocardium, conduction system, or myocardium; narrowing of the small coronary arteries may also be present. Areas of myocardial infarction and malpositioning of myocardial fibers may be present.

Myocardial hypertrophy and its accompanying changes increase the stiffness of the ventricular wall. In addition, early active myocardial relaxation may be delayed and incomplete, especially in the presence of myocardial ischemia. This further reduces ventricular compliance and contributes to diastolic dysfunction. Ventricular stiffness impairs left ventricular filling and increases diastolic pressure. The volume of the left ventricle remains normal or decreases. Decreased ventricular volume causes a decrease in stroke volume, which may contribute to neurohormonal activation. A higher heart rate further affects left ventricular filling, contributing to myocardial ischemia, pulmonary venous congestion, and edema, shortening the duration of diastolic filling. Contractility or systolic function is usually normal in affected cats. However, some cats gradually develop systolic ventricular failure and ventricular dilatation.

The progressive increase in left ventricular filling pressure leads to an increase in pressure in the left atrium and pulmonary veins. The result may be progressive left atrial enlargement and pulmonary congestion and edema. The degree of left atrial enlargement varies from mild to severe. Thrombi are sometimes found in the lumen of the left ventricle or attached to the wall of the ventricle, although they are more commonly found in the left atrium. Arterial thromboembolism is a major complication of HCM, as is the case with other forms of cardiomyopathies in cats. Some affected cats develop mitral insufficiency. Changes in left ventricular geometry, papillary muscle structure, or systolic motion mitral valve(Systolic anterior leaflet movement (SAM) can prevent the valve from closing normally. Valvular insufficiency contributes to an increase in left atrial size and pressure.

Systolic dynamic left ventricular outflow tract obstruction occurs in some cats. This phenomenon is also called hypertrophic obstructive cardiomyopathy or functional subaortic stenosis. Excessive asymmetric hypertrophy of the base of the interventricular septum may be evident on echocardiogram and at autopsy. Systolic outflow tract obstruction increases left ventricular pressure, adversely affects the ventricular wall, increases myocardial oxygen demand, and contributes to myocardial ischemia.

Mitral regurgitation increases the tendency for the anterior leaflet of the mitral valve to move toward the interventricular septum during ventricular systole (SAM). Increased turbulence in the outflow tract of the left ventricle often causes systolic murmur different intensity these cats.

Various factors likely contribute to the development of myocardial ischemia in cats with HCM. These include narrowing of the intramural coronary arteries, increased left ventricular filling pressure, reduced perfusion pressure in coronary arteries and insufficient density of myocardial capillaries depending on the degree of hypertrophy. Tachycardia promotes ischemia by increasing myocardial oxygen demand while decreasing diastolic coronary perfusion time. Ischemia impairs early active ventricular relaxation, which later increases ventricular filling pressure and eventually leads to myocardial fibrosis. Ischemia can cause arrhythmia and possibly chest pain.

Atrial fibrillation and other tachyarrhythmias further disrupt diastolic filling and increase venous congestion; especially detrimental are the loss of normal atrial contractions and the increased heart rate associated with atrial fibrillation. Ventricular tachycardia or other arrhythmias may lead to syncope or sudden death. Pulmonary venous congestion and edema are caused by increased pressure in the left atrium. Increased pulmonary venous and capillary pressure causes pulmonary vasoconstriction; increased pulmonary arterial pressure and symptoms of secondary right-sided congestive heart failure may occur. Over time, some cats with HCM develop refractory biventricular insufficiency with massive pleural effusion. The effusion is usually a modified transudate, although it may be (or become) chylous.

Clinical manifestations

HCM is most common in middle-aged male cats, but clinical signs can occur at any age. Cats with mild disease may be asymptomatic for several years. Symptomatic cats most commonly present with varying degrees of respiratory symptoms or symptoms of acute thromboembolism. Respiratory symptoms include tachypnea; dyspnea associated with activity; dyspnoea and very rarely cough (which can be confused with vomiting). The onset of the disease can be acute in sedentary cats, even if pathological changes develop gradually. Sometimes lethargy and anorexia are the only manifestation of the disease. Some cats experience syncope or sudden death without other symptoms. stresses such as anesthesia, surgical operations, fluid injection, systemic disease(eg hyperthermia or anemia) or transportation may contribute to the manifestation of heart failure in compensated cats. Asymptomatic disease is detected in some cats by detecting heart murmurs or gallops on routine auscultation.

Systolic murmurs due to mitral regurgitation or left ventricular outflow tract obstruction are common. Some cats do not have audible murmurs, even those with severe ventricular hypertrophy. A diastolic gallop sound (usually S4) may be audible, especially if heart failure is obvious or imminent. Cardiac arrhythmias are relatively common. The femoral pulse is usually strong. except in cases of distal aortic thromboembolism. The heartbeat is often amplified. Increased breath sounds, pulmonary rales, and sometimes cyanosis accompany severe pulmonary edema. Crackles in the lungs are not always audible with pulmonary edema in cats. Pleural effusion usually attenuates ventral lung sounds. Physical examination may be normal in subclinical cases.

Diagnosis

Radiography

Radiographic features of HCM include left atrial enlargement and varying degrees of left ventricular enlargement. The classic dorsoventral and ventrodorsal view of the heart in the form of a valentine is not always present, although the position of the left ventricular apex is usually preserved. The silhouette of the heart appears normal in most cats with mild HCM. Dilated and tortuous pulmonary veins may be seen in cats with chronic increase pressure in the pulmonary veins and left atrium. Left-sided congestive heart failure causes patchy infiltrates expressed to varying degrees with interstitial or alveolar pulmonary edema. Radiographically, the distribution of pulmonary edema is variable; there is usually a diffuse or localized distribution within the lung fields, in contrast to the characteristic hilar distribution of cardiogenic pulmonary edema in dogs. Pleural effusion is common in cats with advanced or biventricular congestive heart failure.

Electrocardiography

Most cats with HCM (up to 70%) have electrocardiographic abnormalities. These include abnormal left atrial and left ventricular enlargement, ventricular and/or (less often) supraventricular tachyarrhythmias, and signs of left bundle branch block. Occasionally, atrioventricular conduction delay, complete atrioventricular block, or sinus bradycardia occur.

echocardiography

Echocardiography is best method diagnosis and differentiation of HCM from other diseases. The extent of hypertrophy and its distribution within the free wall of the left ventricle, interventricular septum and papillary muscles is detected in M-mode and B-mode echo studies. Doppler sonography can demonstrate left ventricular systolic and diastolic abnormalities.

Widespread myocardial thickening is commonly encountered, and hypertrophy is often seen asymmetrically in the left ventricular free wall, ventricular septum, and papillary muscles. Focal areas of hypertrophy also occur. Using the B-Mode helps ensure that right direction scanning. Standard M-Mode measurements should be taken, but areas of thickening outside of these standard positions should also be measured. Diagnosis at early stage disease may be suspected in cats with mild or only focal thickening. False positive thickening (pseudohypertrophy) may occur with dehydration and occasionally with tachycardia. False diastolic thickness measurements also occur when the ultrasound beam does not cross the wall/septum perpendicularly and when measurements are not made at the end of diastole, which can occur without a simultaneous ECG, or when using B-Mode is insufficient for a good measurement. A free wall thickness of the left ventricle or interventricular septum (correctly measured) greater than 5.5 mm is considered abnormal. Cats with severe HCM have a diastolic septal or left ventricular free wall thickness of 8 mm or more, although the degree of hypertrophy does not necessarily correlate with severity. clinical symptoms. Doppler measures of diastolic function, such as isovolumic relaxation time, mitral inlet, and pulmonary vein velocity, as well as tissue Doppler imaging techniques, are being increasingly used to characterize disease.

Hypertrophy of the papillary muscles can be pronounced and obliteration of the left ventricle in systole is observed in some cats. Increased echogenicity (brightness) of papillary muscles and subendocardial areas is usually a marker of chronic myocardial ischemia with resulting fibrosis. The shortening fraction of the left ventricle is usually normal or increased. However, some cats have mild to moderate left ventricular dilatation and reduced contractility (contraction fraction 23-29%; normal contractility fraction 35-65%). Occasionally, right ventricular enlargement and pleural or pericardial effusion are seen.

Cats with dynamic left ventricular outflow tract obstruction also often have mitral valve SAM or early leaflet closure. aortic valve detected during the study in the M-mode. Doppler ultrasound can show mitral regurgitation and turbulence in the outflow tract of the left ventricle, although the location of the ultrasound beam along the blood stream with maximum speed ventricular ejection is often difficult and easy to underestimate the systolic gradient.

Left atrial enlargement can be mild to severe. Spontaneous enhancement (rotation, smoke echo) is seen within the enlarged left atrium in some cats. This is thought to be the result of blood stasis with cell aggregation and is a precursor to thromboembolism. Thrombosis is sometimes visualized within the left atrium, usually in its ear.

Other causes of myocardial hypertrophy must be excluded before idiopathic HCM is diagnosed. Thickening of the myocardium can also occur due to infiltrative disease. Variations in myocardial echogenicity or wall irregularity can be detected in such cases.

Excess connective tissue looks like bright. linear echoes within the cavity of the left ventricle.

Clinicopathological features

Cats with moderate to severe HCM have high concentrations of circulating natriuretic peptides and cardiac troponins. Congestive heart failure cats have been found to have varying degrees of elevated plasma concentrations of tumor necrosis factor (TNF).

Picture 1

Radiographic findings in feline HCM. Lateral (A) and dorsoventral (B) views showing left atrial enlargement and mild ventricular enlargement in a male domestic shorthair cat. Lateral view in a cat with HCM and severe pulmonary edema

A distinctive feature of cats is their unprecedented vitality, and due to this feature, in some ancient religions, magical abilities were assigned to animals, and it was also believed that mysterious fluffy beauties were associated with the other world.

But there are diseases that can turn the notorious cat's "nine lives" into one, and even then not too long. One such disease is cardiomyopathy in cats.

This is a disease characterized by pathological changes in the ventricles of the heart and interventricular septa. The disease belongs to the category of dangerous ailments that can significantly shorten the life of an animal. According to statistics, such problems are more common in males than in females.

Varieties of the disease

The definition of "cardiomyopathy" includes four categories of diseases that affect the heart muscle of an animal.

Cardiomyopathy is a pathology that affects the heart of a cat.

The main types of ailments include:

Hypertrophic cardiomyopathy (HCM). This form of the disease is considered the most common and occurs against the background of thickening of the walls of the heart and an increase in the size of this organ. The result of such pathological processes is a reduction in the volume of blood passing through the arteries, poor nutrition and poor oxygen supply to the heart.
Dilated cardiomyopathy (DCM) when the volume of the heart increases, but the thickness of the muscle tissue does not change. As a result, the muscles become thinner and lose their ability to normal contraction, which leads to the development oxygen starvation throughout the body.
Restrictive cardiomyopathy (RCM), which is characterized by fibrosis of the heart muscles. With the development similar shape ailment, the body becomes rigid and loses elasticity, as a result of which the animal’s body stops receiving oxygen and nutrients in the required quantities. With such disorders, animals rarely live beyond the age of two.
Intermediate cardiomyopathy (ICM). There is no description of this type of disease in specialized reference books, since such a diagnosis is made when the animal has symptoms of several types of cardiomyopathies at the same time.

Heart disease has a significant impact on the well-being, behavior and life expectancy of cats. For this reason, it is important to recognize the disease in a timely manner and take the necessary measures; inaction can lead to rapid death. pet.

Reasons for the development of cardiomyopathy

What are the reasons for the development of hypertrophic cardiomyopathy in, or manifestations of other types of this disease?

The factor provoking the development of the disease is heredity.

There are the following provoking factors:

heredity;
congenital pathologies of the heart;
the presence of neoplasms and lymphomas;
respiratory diseases ();
infections and viruses ();
arterial hypertension;
violation of metabolic processes;
increased activity of the thyroid gland;
overproduction of growth hormones.

Also at risk for heart problems are animals that are obese and lead sedentary image life.

Symptoms and clinical picture of the disease

The danger of cardiomyopathy lies in the fact that the animal is capable of for a long time look perfectly healthy and show no signs of illness. In such cases, only an experienced veterinarian can determine that a cat has heart problems when examining a pet.

Symptoms that indicate the presence of a disease of this kind are:

Decrease or increase in heart rate. Each body has its own norm for the number of heartbeats in 1 minute. If the indicator changes up or down, this is a sign of a malfunction of the organ.
Noises in the heart. This symptom can be detected as a result of careful listening to the chest with a phonendoscope, and it indicates changes in the functioning of the organ.
Violation of the heart rhythm. Certain failures are typical for various diseases this organ, including cardiomyopathy.
The appearance of the "third tone". When the cat's heart is healthy and working normally, muscle contractions are heard as two tones. For problems with the heart valve, another one is added to them.

As mentioned above, there are situations when such a violation does not affect the behavior of the animal. But if the cat has become inactive and lethargic, you should immediately contact your veterinarian. It is possible that the specialist will detect signs of heart disease.

If the cat suddenly began to move less, looks lethargic - it should be seen by a doctor.

Diagnosis of cardiomyopathy

If cardiomyopathy is suspected, the following diagnostic measures are carried out:

Visual inspection of the animal. With problems with the heart, the mucous membranes often become bluish.
Blood test, general and biochemical, to assess the condition of the animal and confirm or exclude the presence of infection in the body.
Radiography of the heart. When conducting this study, you can see that the organ is enlarged in size, and if the process has also affected the lungs, then with the help of an X-ray their swelling is revealed.
Echocardiography. Such a diagnostic measure allows you to assess the condition of the ventricles of the heart and interventricular septa.
ECG. Since cardiomyopathy is characterized by changes in the work of the heart and arrhythmia, this study will help identify such pathologies.

After conducting the necessary studies and making a diagnosis, a specialist prescribes treatment.

Treatment of the disease and drugs used

Cardiomyopathy is treated with medication. The goal of therapy is to normalize cardiac output, reduce risk and reduce congestion. In addition, it is necessary to prevent the formation of blood clots and control the work of the heart.

With cardiomyopathy, the veterinarian prescribes the drug Diltiazem.

To deal with the problem and improve general state animal, the following drugs are used:

Calcium channel blockers (Kardizem and Diltiazem). These medicines can normalize the heartbeat and improve the condition of the heart muscles.
Beta blockers (Atenolol). The action of these drugs is aimed at normalizing heart rhythms, they are used in cases where pronounced signs of tachycardia and muscle fibrosis are found.
Decongestants (Furosemide). Cats should be given diuretics to prevent pulmonary edema and congestion.
ACE inhibitors (Benazepril and Enalapril). The action of these medicines is aimed at reducing pathological manifestations in the ventricles of the heart and interventricular septa.

Since the use of diuretics can lead to dehydration, the animal needs additional infusions of 5% glucose solution at the rate of 15 ml per 1 kg of body weight. In addition, it will be necessary to reduce stressful situations for the animal, as they can provoke sudden stop heart and have regular check-ups with the veterinarian.

Diet for cats with heart disease

To increase the effectiveness of the treatment, it is necessary to feed the cat in accordance with a special diet.

Principle proper nutrition consists in the exclusion of salt from the diet of the animal. As you know, this supplement retains fluid in the body, which can lead to the development of edema, which is highly undesirable in heart disease.

In addition, it is important that in the diet of a cat in enough the following substances were present:

polyunsaturated fatty acids;
l-carnitine;
taurine.

To make up for the lack of these elements, it is necessary to purchase special nutritional supplements for cats. Today, many manufacturers produce vitamins for animals suffering from cardiovascular pathologies, and choosing the right complex is not difficult.

Prognosis for cardiomyopathy

When signs of cardiomyopathy are found in a pet, pet owners often ask the question: how long do cats with a similar pathology live.

The prognosis for feline cardiomyopathy is mixed.

With such diseases, the prognosis is very ambiguous and it all depends on the individual characteristics of the animal's body, as well as the nature of the violation.

As a rule, what the outcome of the disease will be is noticeable already in the first days after the start of treatment. If after 2-3 days the animal's condition shows visible improvement, one can hope for a favorable outcome of the disease. However, this is only possible if all the recommendations of the attending physician are followed and the animal is provided with peace.

In situations where, despite the ongoing therapy, the animal's health does not improve, and deterioration is noticeable, a quick death is quite likely.

With heart problems, some animals calmly live up to old age, but there are cases when, despite the efforts of the owners and the efforts of doctors, the animal dies at the age of 1 to 2 years.

Prevention of heart disease in cats

It is possible to prevent heart disease in animals if preventive measures are followed.

The set of activities includes:

and taking vitamins
carrying out the necessary vaccination;
regular check-ups at the veterinarian;
obligatory ultrasound procedure hearts in cats over 6 months of age;
timely and competent treatment emerging diseases.

In addition, it is important to purchase animals from trusted breeders with a good reputation. Otherwise, there is a risk of acquiring a pet with a predisposition to various diseases.

In the video, the veterinarian talks about the disease cat cardiomyopathy.

Cardiomyopathy- a collective concept, which is understood as a whole group of heart diseases, characterized by degenerative changes in the myocardium (heart muscle).

According to the nature of the changes occurring in the heart, there are several types of cardiomyopathies. The main and most common are Hypertrophic cardiomyopathy (HCM) and Dilated cardiomyopathy (DCM).

HCM is characterized by thickening of the walls (totally or only one area) and a decrease in the cavity of the ventricles of the heart. This is the most common form of cardiomyopathy in cats (about 65% of all cardiomyopathy in cats).

DCM, on the contrary, is characterized by thinning of the walls and expansion of the cavities of the ventricles. It is relatively rare (about 5%).

It is necessary to say the same about other forms of cardiomyopathy: RCMP (restrictive cardiomyopathy, as well as with HCM, pathological process captures the left ventricle, but myocardial thickening is less pronounced), ARVD (arrhythmogenic right ventricular dysplasia)- changes affect mainly the right ventricle), in some cases, transformations in the heart are difficult to unambiguously interpret, such diseases are classified as "Unclassified cardiomyopathies".

Causes of the disease

Depending on the causes that caused cardiomyopathy, there are:

Primary or idiopathic. It is believed that this form of the disease is of a genetic nature. At the moment, gene mutations have been identified that lead to HCM in the Maine Coon and Ragdoll cat breeds. Several other breeds, including the British Shorthair, American Shorthair, Scottish Fold, Sphynx, Persian, Norwegian Forest, have a familial predisposition to hypertrophic cardiomyopathy. In these breeds, inherited forms are also assumed, research in this area is ongoing. It is also believed that Abyssinian, Thai, Burmese, Siamese cats are predisposed to DCM. In rare cases, idiopathic cardiomyopathy is also detected in outbred animals.

Fig.2. Maine Coon cats

Fig.3 British Shorthair

Fig.4 Sphinx

Secondary a form of the disease is suspected in cases where there is a disease that caused changes in the myocardium. For example, arterial hypertension, hyperthyroidism, inflammatory process in the heart muscle - myocarditis, heart defects (aortic stenosis), and to DCMP - a lack of taurine with unbalanced feeding, myocarditis, heart defects.

Fig.5 Burmese cat

Fig.6 Abyssinian cat

Mechanism of occurrence of the disease (pathogenesis)

The pathological process can affect different parts of the myocardium, but highest value in the manifestation of the disease has damage to the myocardium of the left ventricle. In DCM, this is a decrease in the “pumping” function, the inability of the ventricle to adequately contract and push blood into big circle circulation. And with HCM, on the contrary, this is the inability of the heart muscle to relax, and, as a result, the insufficiency of the volume of blood entering the systemic circulation. Whatever the cause of the changes, these changes lead to an increase in pressure in the left atrium, and in the future, an increase in pressure in the pulmonary veins - the vessels through which blood enters the left atrium. Then the pressure in the smaller vessels and capillaries of the lungs increases and, as a result, pulmonary edema develops, sometimes hydrothorax. These are the most formidable manifestations of the disease, which can lead to the death of the animal.

Involvement in the process of "right parts of the heart" is sometimes the cause of accumulation of fluid in abdominal cavity(ascites), chest cavity (hydrothorax), pericardium.

In addition to these obvious symptoms, a whole cascade of adaptive reactions follows, which subsequently lead to irreversible changes, both in the heart itself and in other organs. These processes include tachycardia (uncontrolled prolonged increase in heart rate), arterial hypertension(increase blood pressure), vasoconstriction (vasoconstriction), thirst (rare in cats).

Clinical picture

In the early stages of the disease, and sometimes with more pronounced changes in the heart, there may be no symptoms. In some cases, you may notice that the cat has become less mobile, with physical activity, the respiratory rate increases. Such a “hidden” stage can last quite a long time, the symptoms begin to increase, as a rule, after some provoking factor: stress, surgical intervention, anesthesia.

The main manifestation of the disease is shortness of breath - shortness of breath. If at the beginning of the disease it can manifest itself imperceptibly, for a short time, mainly after physical activity, then over time it progresses, manifests itself already at rest. With the development of pulmonary edema, the cat takes a forced posture, often breathes with an open mouth, you can notice that the tongue and gums become bluish. If in this situation you do not provide emergency assistance the animal will die.

Another complication that develops with cardiomyopathies in cats is vascular thromboembolism. A thrombus formed in the dilated chambers of the heart, breaking off, begins to migrate through the blood vessels. The manifestations of thromboembolism depend on which vessel the thrombus stops and clogs it. The most common localization is the femoral arteries. In this case, paresis of the pelvic limbs develops. The cat does not rest on its paws, the fingertips are cold, the pulse on the affected limbs is not palpable. As a rule, there is a pronounced pain syndrome.

In some, very rare cases, the only manifestation of the disease may be sudden death.

How to identify?

The "gold standard" in the diagnosis of cardiomyopathies is the echocardiographic method (ECHO of the heart).

For Maine Coon and Ragdoll cats, there are special genetic tests for the presence of mutations that cause HCM (HCM - test). But this test does not preclude Echocardiography, since the presence of this mutation does not mean the presence of the disease itself. The disease may develop later different forms and varying degrees of severity. Changes detected by echocardiography are the basis for starting treatment. Similarly, a “negative” result does not preclude an echocardiogram. It has been proven that the disease can develop in animals with a "negative" test for HCM, it is assumed that the disease is polygenic in nature (more than 400 mutations of genes leading to HCM are known in humans).

Genetic testing of cats is necessary, first of all, for planning breeding work, culling from breeding individuals that are carriers of mutated genes.

In addition to echocardiography, during a cardiac examination, electrocardiography (ECG) may be required to detect complications in the form of cardiac arrhythmias. In addition, in some situations, x-rays, ultrasound of the chest cavity, and laboratory tests are used.

How to treat?

Treatment is aimed at eliminating the symptoms of congestive heart failure and preventing pulmonary edema, diuretic drugs are prescribed for this purpose. In order to understand the severity of congestion, use the test for counting respiratory movements per minute. This is a simple way to assess the condition of the animal at home, which even the owner can use. To do this, at rest, the respiratory movements are counted (that is, each inhalation-exhalation) per minute. Normally, the respiratory rate does not exceed 27 breaths per minute.

For the treatment of chronic heart failure, drugs from the group of ACE inhibitors are prescribed.

When dilated heart chambers are detected, thrombosis prevention is necessary; for this, as a rule, drugs from the group of antiplatelet agents are prescribed.

β-blockers are sometimes used to control tachycardia and improve myocardial compliance (in HCM).

In some situations, drugs that enhance contractility myocardium.

Treatment should be prescribed by a veterinary cardiologist based on the examination of the cat.

How long will a cat live?

Despite the common principles and stages of the development of the disease, predicting the life expectancy of cats with cardiomyopathy is a rather complicated issue. Even the same forms of cardiomyopathy in different animals are individual, so the life expectancy and severity of the disease can vary significantly. This is because, in addition to the causes of the disease, there are a number of external and internal factors (such as stress, accompanying illnesses and even the nature of the cat), which can influence the course of the disease.

What to do? prevention

Prevention is early detection diseases and competent breeding work. There are no drugs with proven effectiveness that prevent the development of the disease. Therefore, it is very important to detect the disease in time.

Cats of at-risk breeds* prior to surgery under general anesthesia.
Regularly for animals of risk group breeds* every 1-1.5 years until the age of five.
For older cats over 6 years of age surgical intervention under general anesthesia.
Animals demonstrating rapid breathing with slight exertion or at rest, increased fatigue during exertion or when heart murmurs, rhythm disturbances are detected during a therapeutic examination.

Cardiomyopathy- a collective concept, which is understood as a whole group of heart diseases, characterized by degenerative changes in the myocardium (heart muscle).

DCM, on the contrary, is characterized by thinning of the walls and expansion of the cavities of the ventricles. It is relatively rare (about 5%).

It is necessary to say the same about other forms of cardiomyopathy: RCMP (restrictive cardiomyopathy, as well as in HCM, the pathological process captures the left ventricle, but myocardial thickening is less pronounced), ARVD (arrhythmogenic right ventricular dysplasia)- changes affect mainly the right ventricle), in some cases, transformations in the heart are difficult to unambiguously interpret, such diseases are classified as "Unclassified cardiomyopathies".

Causes of the disease

Depending on the causes that caused cardiomyopathy, there are:

Fig.2. Maine Coon cats

Fig.3 British Shorthair

Fig.4 Sphinx

Secondary a form of the disease is suspected in cases where there is a disease that caused changes in the myocardium. So, for example, arterial hypertension, hyperthyroidism, inflammation in the heart muscle - myocarditis, heart defects (aortic stenosis) can lead to secondary myocardial hypertrophy, and taurine deficiency with unbalanced feeding, myocarditis, heart defects.

Fig.5 Burmese cat

Fig.6 Abyssinian cat

Mechanism of occurrence of the disease (pathogenesis)

The pathological process can affect various parts of the myocardium, but the most important in the manifestation of the disease is the defeat of the myocardium of the left ventricle. In DCM, this is a decrease in the "pumping" function, the inability of the ventricle to adequately contract and push blood into the systemic circulation. And with HCM, on the contrary, this is the inability of the heart muscle to relax, and, as a result, the insufficiency of the volume of blood entering the systemic circulation. Whatever the cause of the changes, these changes lead to an increase in pressure in the left atrium, and in the future, an increase in pressure in the pulmonary veins - the vessels through which blood enters the left atrium. Then the pressure in the smaller vessels and capillaries of the lungs increases and, as a result, pulmonary edema develops, sometimes hydrothorax. These are the most formidable manifestations of the disease, which can lead to the death of the animal.

Involvement in the process of "right parts of the heart" is sometimes the cause of accumulation of fluid in the abdominal cavity (ascites), chest cavity (hydrothorax), pericardium.

In addition to these obvious symptoms, a whole cascade of adaptive reactions follows, which subsequently lead to irreversible changes, both in the heart itself and in other organs. Such processes include tachycardia (uncontrolled prolonged increase in heart rate), arterial hypertension (increased blood pressure), vasoconstriction (vasoconstriction), thirst (rare in cats).

Clinical picture

The main manifestation of the disease is shortness of breath - shortness of breath. If at the beginning of the disease it can manifest itself imperceptibly, for a short time, mainly after physical exertion, then over time it progresses, manifesting itself already at rest. With the development of pulmonary edema, the cat takes a forced posture, often breathes with an open mouth, you can notice that the tongue and gums become bluish. If emergency assistance is not provided in this situation, the animal will die.

In some, very rare cases, the only manifestation of the disease may be sudden death.

How to identify?

The "gold standard" in the diagnosis of cardiomyopathies is the echocardiographic method (ECHO of the heart).

For Maine Coon and Ragdoll cats, there are special genetic tests for the presence of mutations that cause HCM (HCM - test). But this test does not preclude Echocardiography, since the presence of this mutation does not mean the presence of the disease itself. The disease can develop later, in different forms and varying degrees of severity. Changes detected by echocardiography are the basis for starting treatment. Similarly, a “negative” result does not preclude an echocardiogram. It has been proven that the disease can develop in animals with a "negative" test for HCM, it is assumed that the disease is polygenic in nature (more than 400 mutations of genes leading to HCM are known in humans).

Genetic testing of cats is necessary, first of all, for planning breeding work, culling from breeding individuals that are carriers of mutated genes.

How to treat?

For the treatment of chronic heart failure, drugs from the group of ACE inhibitors are prescribed.

When dilated heart chambers are detected, thrombosis prevention is necessary; for this, as a rule, drugs from the group of antiplatelet agents are prescribed.

β-blockers are sometimes used to control tachycardia and improve myocardial compliance (in HCM).

In some situations, drugs that enhance myocardial contractility are needed.

Treatment should be prescribed by a veterinary cardiologist based on the examination of the cat.

How long will a cat live?

Despite the common principles and stages of the development of the disease, predicting the life expectancy of cats with cardiomyopathy is a rather complicated issue. Even the same forms of cardiomyopathy in different animals are individual, so the life expectancy and severity of the disease can vary significantly. This is because, in addition to the causes of the disease, there are a number of external and internal factors (such as stress, concomitant diseases, and even the nature of the cat) that can influence the course of the disease.

What to do? prevention

Prevention consists in early detection of the disease and competent breeding work. There are no drugs with proven effectiveness that prevent the development of the disease. Therefore, it is very important to detect the disease in time.

Cats of at-risk breeds* prior to surgery under general anesthesia.
Regularly for animals of risk group breeds* every 1-1.5 years until the age of five.
Older cats over 6 years old before surgery under general anesthesia.
Animals demonstrating rapid breathing with slight exertion or at rest, increased fatigue during exertion or when heart murmurs, rhythm disturbances are detected during a therapeutic examination.

Sourced from www.icatcare.org

Hypertrophic cardiomyopathy- a disease in which there is a thickening (or hypertrophy) of the wall of the ventricle of the cat's heart. As a result, the internal volume of the ventricle (the main chamber of the heart) decreases, which leads to a decrease in the amount of blood pumped per contraction.

Hypertrophic cardiomyopathy is the most common form of heart disease in cats and can lead to heart failure. thromboembolism, and sometimes even to the sudden death of a cat.

The genetic nature of hypertrophic cardiomyopathy in cats.

Hypertrophy (thickening) of the walls can be secondary, that is, caused by some other disease (for example, hyperthyroidism or hypertension), but, in most cases, is idiopathic (having no established cause) and is considered a primary disease - a disease of the heart itself.

Most cases of hypertrophic cardiomyopathy in humans have a genetic basis. Currently, more than 130 genetic mutations have been identified that cause a predisposition to develop this disease. There is evidence to suggest that many cases of hypertrophic cardiomyopathy in cats are also genetic.

Specific genetic mutations have been identified for Maine Coon and Ragdoll cats. Mutations in the genes responsible for the production of the corresponding proteins in heart cells - MYBPC3 (from the English "cardiac myosin binding protein C" - cardiac myosin-binding protein), were found in cats of both these breeds suffering from hypertrophic cardiomyopathy. Although, it should be noted that mutations for each breed are different, in addition, similar mutations were found in cats of other breeds.

Research is currently ongoing to identify other mutations that may contribute to the development of the disease not only in Maine Coons and Ragdolls, but also in other breeds of cats (for example, Norwegian Forest and Sphynx), among which the prevalence of hypertrophic cardiomyopathy is also increased.

It is believed that the presence of defective genes increases the risk of developing hypertrophic cardiomyopathy in cats. Since chromosomes are always found in pairs in DNA, there is an increased risk in homozygous cats (with defective genes on each of the paired chromosomes) compared to heterozygous cats (one normal and one defective chromosome).

The defective genes are the same in Maine Coon and Ragdoll cats, with some studies showing that at least 30-40% of affected cats carried one or both of the defective genes. However, the relationship between the presence of a mutation in the genes and hypertrophic cardiomyopathy is not unambiguous. Although the presence of a defect increases the risk of developing the disease, hypertrophic cardiomyopathy is not observed in all cats of these breeds that carry the defective genes. It is likely that there are other (as yet unidentified) gene defects, as well as environmental and biological factors, that influence the development of hypertrophic cardiomyopathy in cats.

Diagnosis of hypertrophic cardiomyopathy in cats.

Measurement of the thickness of the walls of the chambers of the heart, carried out by ultrasound, can reveal hypertrophic cardiomyopathy in a cat. The matter is complicated by the fact that in some cats suffering from hypertrophic cardiomyopathy, ultrasound does not show abnormalities in the state of the heart in cases where the changes do not become serious. In such cases, special genetic tests are also needed for diagnosis. Such tests are now available in many veterinary clinics.

For representatives of cat breeds such as Maine Coon and Ragdoll, for which hypertrophic cardiomyopathy is not uncommon, it is important to identify genetic predisposition to the disease. Ideally, cats of these breeds should be examined using both an ultrasound scan of the heart and genetic tests on blood samples or mouth swabs in specialized laboratories to accurately determine the genetic status of the animal.

Prevention of hypertrophic cardiomyopathy in cats.

It is recommended not to breed cats with confirmed hypertrophic cardiomyopathy with partners for whom genetic tests have shown positive result on both chromosomes (homozygous for this defect), since kittens will inevitably inherit the defect. The risk of disease in this case will be very high.

The question of participation in selection of cats with a positive heterozygous status (one normal gene and one mutant) should be carefully considered. Such cats will inevitably pass on the defect to some part of their kittens. Although when choosing cats for breeding, there are many various factors, high prevalence clinical form Hypertrophic cardiomyopathy caused by gene defects in cat breeds such as the Maine Coon and Ragdoll means that one must be very careful in selecting such animals. to gradually reduce the presence of defective genes in these breeds, thus reducing the risk of developing hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy in cats can manifest itself at any age, so a single cardiac ultrasound showing the absence of abnormalities is not a guarantee that there is no problem. Cardiologists recommend an annual echocardiogram for cats involved in breeding programs. It also makes sense to periodically examine cats no longer bred, as this may allow the identification of possible carriers of the defect among their offspring.

In some countries, when registering breeding cats, along with the genetic status, the results of ultrasound are also indicated with comments from a veterinary cardiologist. This information allows you to better match pairs for breeding cats.

Hypertrophic cardiomyopathy in cats.

Hypertrophic cardiomyopathy

Hypertrophic cardiomyopathy (HCM) in cats is a dangerous disease that occurs as a result of excessive thickening of the heart muscle. With thickening of the heart muscle, the myocardium loses its ability to relax, which leads to a decrease in the volume of circulating blood. This leads to disruption of the heart and, as a consequence, to the development of heart failure.

HCM is among the most common heart diseases in cats.

The reasons

The exact cause of hypertrophic cardiomyopathy has not yet been named. However, risk groups have been identified among the following breeds cats:

– ragdoll

- Maine Coon

– sphinx

- Scottish fold

- British and American Shorthairs

- Persian

- Norwegian forest

It is no coincidence that the Ragdoll and Maine Coon breeds are in the first place on this list. In these breeds, specific genes responsible for the occurrence of HCM have been identified. Currently, Ragdoll and Maine Coon cats can be tested for the presence of a dangerous gene.

Hypertrophic cardiomyopathy is very insidious disease. The first symptom of this disease can be thromboembolism, pulmonary edema, and even death. Sometimes in the early stages of the disease, shortness of breath and fatigue may occur.

The most common complication associated with HCM is thromboembolism. It can occur suddenly, against the background of apparent well-being. Blood clots arising as a result of the disease can block vital vessels in the animal's body. The femoral arteries are most often blocked. In this case, the first symptom of the disease is a sudden paralysis of the pelvic limbs with severe pain syndrome. The cat is screaming, can't stand up hind legs.

In these cases, your pet's life depends on the speed of circulation in veterinary clinic.

Diagnostics

Since HCM is very difficult to treat on late stages, then the disease should be detected as soon as possible. The sooner treatment is started, the greater the chance of a good prognosis.

Methods for diagnosing HCM are as follows:

- echocardiography (ultrasound examination of the heart)

- chest x-ray

– electrocardiography

Echocardiography allows not only to detect the disease at an early stage, but also to understand whether there is a risk of its occurrence in the future. It is highly desirable for representatives of breeds that are at risk to undergo examination data even in the absence of visible symptoms illness. This is especially true for animals that will receive anesthesia.

tribal breeding

Animals in which the diagnosis of HCM is confirmed are withdrawn from breeding, in order to avoid the spread of this pathology.

ICD

Hypertrophic cardiomyopathy in cats

AT recent times treatment of owners with cats in extremely serious condition(weakness, shortness of breath, paralysis of the pelvic limbs), pulmonary edema. And also the cases of death of animals from pulmonary edema after planned surgical measures (castration and sterilization) have become more frequent.

What is the cause? The answer, as a rule, in these cases is HYPERTROPHIC CARDIOMYOPATHY.

Hypertrophic cardiomyopathy (HCM) is a disease characterized by hypertrophy (thickening) of the wall of the left and/or occasionally right ventricle. Hypertrophy is often asymmetric, predominantly affected interventricular septum. Characterized by an irregular, chaotic arrangement of muscle fibers in the myocardium. zheludok

HCMP is the most common cause heart failure, arterial thromboembolism and sudden death in cats.

Hypertrophic cardiomyopathy can be primary or secondary.

Primary HCM is a hereditary disease. Occurs - this disease is more common and is caused by mutations in the genes encoding the synthesis of myocardial contractile proteins.

There are breeds that are predisposed to developing HCM. These are Maine Coons, Ragdolls, Sphynxes, British and American Shorthairs, Scottish Folds, Norwegian Forest Cats and some others. That is, kittens inherit this disease from their parents, and by the age of 1-3 years they may develop signs of heart failure. However, this is not a guarantee that your outbred Murka cannot have this pathology, what if her grandmother sinned with a British or Persian cat? kotje

In secondary HCM, changes in the myocardium (heart muscle) develop under the influence of other diseases (for example, with hyperthyroidism). In such animals, signs of heart failure may develop either at a very old age, or not have time to develop at all.

A distinctive feature of this disease is the significant complexity early diagnosis. In a cat with HCM, the presence of the disease may present for the first time with pulmonary edema and/or death. That is, the signs will not develop gradually and for a long time, will not be noticed by the owner, but will immediately and sharply develop severe manifestations illness.

Often signs of heart failure (mostly shortness of breath - rapid breathing and/or open-mouth breathing) the cat or cat begins to demonstrate after stress, which is either transporting the animal or visiting the veterinary clinic for some reason not originally related to heart disease. Only a small percentage of owners of cats diagnosed with HCM can recall noticing that the cat was breathing heavily after exercise (provoked by the owner or other animal of the game). At the same time, the insidiousness of this pathology lies in the fact that during examination, auscultation, and even on a chest x-ray, in the absence of complaints, more than half of the animals with HCM may not have any abnormalities.

The mechanism of development of this pathology lies in the fact that as the heart muscle thickens, the volume of the left ventricle decreases, because of this, the volume of blood pumped through it decreases. Because of this, in turn, pressure in the left atrium rises, it increases, pressure in the vessels of the lungs rises, and then, in later stages, pulmonary edema and / or hydrothorax (accumulation of free fluid in the pleural cavity) develops.

It is possible to know reliably whether a cat has HCM or not only with echocardiography (ultrasound of the heart). Examination, auscultation, X-ray, ECG are additional research, and allow only to suspect that something was wrong.

One of the most frequent and extremely severe complications HCM, which can appear against the background of the absolute apparent well-being of the cat, is thromboembolism (blockage of the vessel by a thrombus that has formed in the enlarged left atrium). Most often, blockage occurs at the level of the femoral arteries, in which case the first symptom will be a sudden paralysis of the pelvic limbs and severe pain - the cat screams, drags its hind legs. In such cases, the count goes to hours, if not minutes. A very small percentage of patients recover, more often these are animals with mild symptoms. In a recovered animal, a relapse (a repetition of the situation) is highly likely in the coming months. Of course, the sooner the patient arrives at the veterinary clinic, the greater the chance of restoring blood flow.

Considering all of the above, it is extremely important timely diagnosis. The sooner the doctor starts treatment, the longer the patient can live and the less the risk of developing adverse complications.

Echocardiography of a cat with no health complaints should be performed if:

a) a cat of a risk group breed;

b) you noticed that the cat is inactive or breathes through an open mouth after exercise;

c) if one of the first two signs is combined with the fact that your pet needs general anesthesia.

As mentioned above, the disease may not manifest itself in any way, the doctor at the appointment during the examination before anesthesia does not reveal changes, while in a cat with HCM, general anesthesia can lead to serious complications in the form of pulmonary edema and death in the next hours or days after surgery. This applies primarily to young animals who have come to the clinic for castration. As a rule, these patients are about a year old, and the vast majority of those who were diagnosed with HCM showed no signs of the disease. The reason for conducting echocardiography in this case was either the doctor's alertness regarding the presence of HCM, or heightened anxiety owners about upcoming anesthesia. The detection of HCM in these animals is not absolute contraindication to general anesthesia, but this is a higher degree of anesthetic risk, this is a different approach to conducting general anesthesia, this is the need for a longer and more careful postoperative observation, the possibility of the owners in the coming days after the operation, in case of complications, urgently contact the clinic.

We wish health to you and your pets!

Deputy chief doctor veterinary center"Hope"

Andreeva Ekaterina Alexandrovna.