Heart murmurs in dogs. Veterinary clinic "Zoostatus"

Tachycardia in dogs is a common heart pathology. This term means an increase in heart rate, and may indicate serious malfunctions in the four-legged pet’s body.

In this article we will look at why tachycardia occurs in dogs, the symptoms and causes of this disease, we will find out how to treat the pathology, and how to prevent it.

Tachycardia in a dog: how to help - Symptoms and treatment of diseases

Today, heart disease is quite common in dogs. They can be congenital or acquired. In addition, they are acute and chronic; in the latter case, the disease may not manifest itself for a long time.

One such common heart disease in dogs is tachycardia.

Description of the disease

Tachycardia is a heart rhythm disorder in which the heart rate increases. You should know that in medium-sized dogs the normal heart rate is 160 beats per minute, in giants it is up to 140, and in puppies this value is 220 beats. With tachycardia, these indicators increase sharply.

Any heart problems, including tachycardia, affect the life expectancy of a pet. A severe form of tachycardia disrupts the functioning of the heart, preventing it from performing its main functions - transporting blood to the organs.

Causes of the disease

The causes of tachycardia can be both physical and pathological.

Excessive physical activity.
Limitation of motor functions.

Pathological reasons are much more diverse:

Feverish condition.
Hypoxia.
Chronic lung diseases.
Dehydration.
Sepsis.
Pregnancy in females.
State of shock.
Oncological diseases.
Presence of fluid in the chest cavity.
Anemia.

Symptoms

The most common symptoms of tachycardia are the following:

Heavy breathing through the mouth, accelerated heartbeat. Such signs can also be observed in dogs after excessive physical exertion. These symptoms disappear if the animal is returned to a resting state.
Weakness, loss of consciousness when performing physical activity.
Pallor of the mucous membranes.
Feverish condition.
Cough and shortness of breath, even if the animal is at rest.

In young dogs, signs of tachycardia may not appear due to the compensatory capabilities of the body.

Predisposing factors

The likelihood of tachycardia in dogs increases if the following factors are present:

Thyroid diseases.
Other heart diseases.
Pulmonary diseases.
Inflammatory processes of various origins.
Pregnancy and the postpartum period in bitches (endometritis or mastitis can provoke tachycardia).

There are breeds that are most susceptible to heart disease, in particular, tachycardia. In these dogs, heart failure occurs at an earlier age than in others.

large breed dogs are at risk : St. Bernards, Shepherds, Mastiffs, Great Danes, Alabais, Newfoundlands. They experience heart problems for several reasons: from active stress on the heart or from lack of mobility. This leads to the fact that dogs’ hearts begin to work worse at a young age.

How to recognize the disease at an early stage?

To recognize tachycardia in the early stages and exclude the development of more severe forms of heart disease, it is necessary to periodically check your pet’s breathing, pulse and temperature.

In one minute, the number of inhalations and exhalations in an animal ranges from 14 to 24 , and the number of heartbeats should not exceed 120 beats per minute. The breathing rate is determined by the way the chest oscillates and by the stream of air coming out of the nose.

The pulse rate is measured at the femoral artery. It should be remembered that young dogs have a faster pulse than older dogs. Bitches and puppies may have a much faster pulse. When body temperature rises and emotional disturbances, the pulse also increases.

In a dog without diseases, the temperature can range from 38 to 39 degrees. Body temperature should be measured with a thermometer through the anus.

Measures aimed at treating tachycardia in dogs

To diagnose tachycardia in an animal, you need to undergo a thorough examination at a veterinary clinic.

To do this, you need to carry out a number of procedures:

Analysis of urine.
Biochemical and clinical blood test.
X-ray examination of the chest (this is necessary to detect tumors and other cardiac abnormalities)
Ultrasound examination (evaluates the functioning of the adrenal glands)
Electrocardiogram (will determine the ability of the heart to contract)

Treatment methods can be very different, depending on the results of the dog's examination. If the diagnosis is confirmed, the veterinarian develops an individual treatment plan for the animal, which depends on the size, age of the dog and the degree of development of the disease.

Conservative treatment is usually carried out, antiarrhythmic drugs are prescribed - Pimobendan, Propafenone.

During the course of the disease, you must be extremely attentive to your pet. Care must be taken to ensure that the dog is not exposed to infectious diseases or colds. It is also necessary to limit the animal’s physical activity and choose the right diet.

Tachycardia in a dog. When the “fiery engine” is at its limit

Tachycardia is the most common cardiac pathology. This term refers to an increase in heart rate.

It must be remembered that the norm for dogs of medium breeds is 160 beats per minute, for giant varieties - up to 140 contractions, the heart of small dogs contracts up to 180 times per minute. In puppies, this value is generally 220 compressions.

Accordingly, tachycardia in dogs involves a sharp increase in these indicators.

Why is this pathology dangerous?

Severe tachycardia can compromise the functional state of the heart, since too high a frequency of contractions shortens the diastolic filling time, that is, the period during which the chambers of the organ fill with blood. As a result, a smaller volume of blood is released into the general bloodstream during one contraction.

Because of this, the amount of nutrients and oxygen spent on feeding the heart itself is significantly deteriorated, while these needs in the body increase. This type of tachycardia occurs most often and is the most “harmless”.

In conditions complicated by the presence of some infectious diseases, this disorder can be much more severe due to the development of myocarditis, endocarditis or pericarditis.

Symptoms of tachycardia in dogs

In relatively young animals, symptoms may often not appear at all, since at first the compensatory capabilities of the body have not yet been completely exhausted.

If tachycardia is associated with a primary heart disease, then the development of additional pathology can be judged by the dog’s extremely rapid fatigue, sometimes sudden fainting occurs, and the dog’s rapid breathing does not disappear for a long time after the slightest exertion.

Pale mucous membranes. Most often this occurs in the presence of anemia or some form of heart failure.

A febrile state that alternates with periods of normal body temperature of the animal.

Cough and cyanosis of the mucous membranes may accompany the most serious manifestations of tachycardia in an animal.

What causes it?

Here it should be said that tachycardia is divided into physiological and pathological. The first occurs when the dog is excited, scared, it appears to the male at the sight of a female, or the animal simply smells tasty food. But this variety is practically indifferent to us.

What is much more “interesting” is pathological tachycardia, the causes of which are extremely diverse:

Problems with the functioning of the heart.

Lung problems of any origin.

Fluid in the chest (hydrothorax or hemothorax).

Infectious diseases, including manifestations of septic blood poisoning.

Cases of physiological tachycardia include low oxygen levels in the blood.

Pulmonary thrombus. Since it is almost impossible to help the dog in this case (death within a few minutes), the presence of this pathology is learned only after an autopsy.

Reduced blood volume (collapse with severe bleeding).

Oncological diseases.

Diagnostics

The veterinarian will perform a complete examination of your dog, taking into account clinical signs (including those you tell him about). A blood test is the first priority. It includes biochemical and microscopic research methods. A urine test will also be done, based on the results of which many dangerous pathologies can be diagnosed.

Fluoroscopy is useful in looking for deformities of the heart and/or lungs. An electrocardiogram (ECG) is important for assessing the passage of electrical impulses in the heart muscles (the contractility of the organ directly depends on this).

Ultrasound and vascular examination are also very useful in assessing the general condition of the dog's cardiac and respiratory systems.

Finally, your veterinarian may do an X-ray of the thyroid gland to look for enlargement, which indicates hyperthyroidism.

Treatment of tachycardia in dogs

What treatment can be used? Here everything depends on the results of diagnostic measures. Since tachycardia is only a symptom of some pathology, therapeutic measures are selected depending on the latter.

Tumor? You can't do without surgery. Parasites in the lungs? Anthelmintic drugs are prescribed.

In any case, drugs are used to maintain respiratory and cardiac activity, diuretics can be used (for hydrothorax), hormonal therapy is also possible.

How to treat tachycardia in dogs?

Tachycardia is an increase in the sinus rhythm of the heart in a medium-sized dog to more than 160 beats per minute. In giant breeds it is more than 140 beats, in toy dogs it is more than 180 beats, and in puppies it is more than 220 beats per minute.

An increased rhythm reduces the time it takes for the chambers of the heart to fill with blood. This leads to disorders of coronary blood flow, as well as an increase in oxygen demand. This is the most common cardiac arrhythmia in dogs that have recently had surgery and is also a reaction to various types of stress.

The causes of tachycardia in dogs can be physical:

active loads,
excitement,
fear,
pain,
limitation of motor functions.

Tachycardia can be triggered by inflammation, medications used to treat thyroid disorders, and pregnancy.

Treatment of tachycardia in dogs

First you need to diagnose tachycardia, which occurs suddenly. To do this, the veterinarian conducts a thorough examination, a urine test, a biochemical blood test, and a blood cell count are needed. This is necessary to detect an organ disorder or blood infection.

A chest x-ray may reveal tumors or heart disease. An electrocardiogram may show abnormalities in the heart's ability to pump.

Ultrasound is useful for assessing the health of the adrenal glands. After confirming the diagnosis, it is first necessary to treat the underlying diseases.

During treatment, you need to look after your dog and may need to limit activity.

Source: https://medportal-24.ru/tahikardiya-u-sobaki-kak-pomoch/

What causes it?

Here it should be said that tachycardia is divided into physiological and pathological. The first occurs when the dog is excited, scared, it appears to the male at the sight of a female, or the animal simply smells tasty food. But this variety is practically indifferent to us.

What is much more “interesting” is pathological tachycardia, the causes of which are extremely diverse:

Lung problems of any origin.

Fluid in the chest (hydrothorax or hemothorax).

Infectious diseases, including manifestations of septic blood poisoning.

Cases of physiological tachycardia include low oxygen levels in the blood.

Pulmonary thrombus. Since it is almost impossible to help the dog in this case (death within a few minutes), the presence of this pathology is learned only after an autopsy.

Reduced blood volume (collapse with severe bleeding).

Tachycardia in dogs: what it is, symptoms, diagnosis and treatment

Tachycardia in dogs is a common heart pathology. This term means an increase in heart rate, and may indicate serious malfunctions in the four-legged pet’s body.

In this article we will look at why tachycardia occurs in dogs, the symptoms and causes of this disease, we will find out how to treat the pathology, and how to prevent it.

Tachycardia: what is it?

Tachycardia is commonly understood as an abnormal heart rhythm, which is characterized by an increase in heart rate. To understand exactly in which cases violations occur, just look at the veterinary reference book.

According to cardiac indicators, in a healthy animal the heart rate (number of beats) per minute is:

for a medium-sized dog - 160;
for representatives of large breeds - 140;
in small dogs and puppies - 220.

If a dog’s characteristic value exceeds the norm, then tachycardia is diagnosed. The disease poses a real threat to the pet's life, significantly reducing its duration. A severe form of the disease reduces cardiac function - it interferes with the circulation of blood to the organs.

In addition, rhythm disturbances lead to the loss of most of the nutrients necessary for various body systems and a decrease in the amount of oxygen entering the heart.

If tachycardia in dogs is accompanied by infectious diseases, other cardiac diseases, such as pericarditis, endocarditis, myocarditis, etc., will most likely develop.

Early symptoms

To stop tachycardia as soon as it appears, you need to be more attentive to your pet’s health, monitoring his well-being and mood. Periodically measure your dog's pulse, temperature, and monitor his breathing. The earlier the onset of tachycardia is detected, the easier it will be to cope with this symptom.

Note that in a normal state, a dog should take from 14 to 24 breaths per minute, and its pulse should not exceed 120 beats. The animal's pulse is usually measured at the femoral artery.

It should be borne in mind that in young dogs and, especially, puppies, for natural reasons, the pulse will be faster than in adults. It is best to “take readings” when the dog is in an even, calm state, since excessive emotions, nervousness, and worries can affect the results of the examination.

Causes of the problem

In young individuals whose body has good compensatory capabilities, tachycardia may not appear.

Failure of the heart rhythm can be triggered by various factors, both predisposing and physical.

Predisposing ones include:

inflammation, infections;
thyroid dysfunction;
pregnancy, postpartum period;
cardiac diseases;
mastitis, endometritis;
fever;
oncology;
dehydration of the body;
anemia;
accumulation of fluid in the chest.

Physical factors include excessive or insufficient physical activity.

Representatives of some breeds have a predisposition to this disease, which can be observed in them from a very early age. In large dogs (working dogs, hunting dogs), physical loads are usually greater, this can lead to the fact that the heart begins to work worse.

There is also the other side of the coin - if such a dog is little exercised or not exercised at all, it may develop tachycardia due to physical inactivity.

Pathology is often observed in miniature dogs. As a rule, such kids are overly emotional, nervous, and in some cases even hysterical. They are accustomed to universal adoration, to being carried in their arms. Lack of attention leads to stress and, as a result, to heart disorders.

Clinical picture

You can determine that a dog has tachycardia by the following signs:

rapid heartbeat at any time, heavy breathing;
anemia, weakness after exercise, long recovery;
pallor of the mucous membranes;
fever;
shortness of breath, cough.

Symptoms such as palpitations and difficulty breathing are normal after exercise. They should alert when the dog is at rest.

Diagnosis and treatment

Before prescribing appropriate treatment, the doctor needs to carry out a number of diagnostic measures. These include: general blood and urine analysis, biochemical blood test, ultrasound, ECG, chest x-ray, echocardiography, as well as additional studies to exclude certain diseases that have signs similar to tachycardia.

In each specific case, the veterinarian prescribes an individual treatment plan, which is developed based on the size, age of the animal, as well as the stage of the disease.

As a rule, treatment is carried out using conservative methods - by prescribing arrhythmic drugs such as Propaferon, Pimobendan, etc.

In some cases, drugs containing potassium (Panangin), sedatives and antipyretics, and cardiac glycosides are indicated.

During treatment, you should be very attentive to your pet, try not to subject it to excessive physical activity, unless the veterinarian, on the contrary, recommends walking and exercising the dog more. Diet adjustments may be necessary if your dog is overweight.

It is necessary to ensure that the dog does not become hypothermic, since colds and infections are very dangerous for him during this period.

Representatives of certain breeds that genetically inherit a tendency to dilated cardiomyopathy and some other heart diseases (boxers, Dobermans, German shepherds, Great Danes), which is accompanied by tachycardia, must be checked by a cardiologist once a year.

Prevention measures include a balanced diet, reasonable physical activity, and lack of stress.

Sources:

https://www.belanta.vet/vet-blog/taxikardiya-sobak-simptomy/

https://realpet.ru/zdorovie/taxikardiya-u-sobak.html

Source: https://moypitomec.ru/sobaki/bolezni/tahikardija-u-sobak.html

Clinical picture

You can determine that a dog has tachycardia by the following signs:

rapid heartbeat at any time, heavy breathing;
anemia, weakness after exercise, long recovery;
pallor of the mucous membranes;
fever;
shortness of breath, cough.

Symptoms such as palpitations and difficulty breathing are normal after exercise. They should alert when the dog is at rest.

If your dog has a fast heartbeat

Congenital or acquired heart disease is as common in dogs as it is in humans. One of these diseases is tachycardia.

Causes of the problem

In young individuals whose body has good compensatory capabilities, tachycardia may not appear.

Failure of the heart rhythm can be triggered by various factors, both predisposing and physical.

Predisposing ones include:

inflammation, infections;
thyroid dysfunction;
pregnancy, postpartum period;
cardiac diseases;
mastitis, endometritis;
fever;
oncology;
dehydration of the body;
anemia;
accumulation of fluid in the chest.

Physical factors include excessive or insufficient physical activity.

Representatives of some breeds have a predisposition to this disease, which can be observed in them from a very early age.

In large dogs (working dogs, hunting dogs), physical loads are usually greater, this can lead to the fact that the heart begins to work worse.

There is also the other side of the coin - if such a dog is little exercised or not exercised at all, it may develop tachycardia due to physical inactivity.

Diagnosis and treatment

In each specific case, the veterinarian prescribes an individual treatment plan, which is developed based on the size, age of the animal, as well as the stage of the disease.

As a rule, treatment is carried out using conservative methods - by prescribing arrhythmic drugs such as Propaferon, Pimobendan, etc.

In some cases, drugs containing potassium (Panangin), sedatives and antipyretics, and cardiac glycosides are indicated.

It is necessary to ensure that the dog does not become hypothermic, since colds and infections are very dangerous for him during this period.

Prevention measures include a balanced diet, reasonable physical activity, and lack of stress.

Authors of the articles: Belanta Clinic team

Source: https://www.belanta.vet/vet-blog/taxikardiya-sobak-simptomy/

What is a heart murmur

A dog's heart murmur is an atypical sound that is detected when listening to the organ with a stethoscope. This condition is associated with abnormal blood flow and occurs when blood passes through abnormal valves or defective heart muscle structures. Murmurs can also be heard in a healthy heart if the blood flows very quickly (for example, when the animal is excited).

It is recommended to immediately contact a veterinarian if your dog exhibits the following symptoms:

cough is one of the most important signs of heart failure;
fatigue;
rapid breathing;
dyspnea;
suffocation;
poor appetite;
increase in abdominal size;
pale or bluish tinge of gums;
fast, low heart rate;
muscle wasting;
fainting (less common).

In older dogs, these symptoms may be confused with signs of old age.

Symptoms of tachycardia in dogs and treatment methods

Disorders of the cardiovascular system in dogs often manifest as tachycardia. This is a type of arrhythmia characterized by a significant increase in heart rate.

In dwarf breeds, tachycardia is diagnosed when the heart rate is more than 180 beats per minute, in representatives of medium-sized breeds - when the heart rate is more than 160 beats per minute.

In dogs of large and giant breeds, a disorder is detected if their heart rate (heart rate) is more than 120 beats per minute. In puppies, the normal heart rate limits are much wider and amount to 220 beats per minute.

A high heart rate in a dog is caused by poor circulation in the coronary arteries and is therefore very dangerous. At this time, her heart chambers are only partially filled with blood, although the heart is actively working. As a result, all organs and systems (including the brain) are not provided with sufficient oxygen. Oxygen starvation gradually develops.

If the disease is not treated, the animal's life expectancy will be reduced. Low efficiency of the heart leads to the appearance of chronic diseases of the cardiovascular system, an increase in the volume of the heart muscle, and its premature wear.

Classification of the disease depending on its causes

Depending on the causes, tachycardia in dogs is of two types: physiological or pathological.

Physiological tachycardia is a variant of the norm. Frequent heartbeat occurs as a response of the body to the influence of certain factors.

This is how the compensatory mechanism of the heart works during physical activity, during stressful situations or during a hot period of time. Activation of the sympathetic nervous system and the release of adrenaline into the blood lead to an increase in heart rate.

This condition is not a pathology. Heart rate normalizes as soon as exposure to adverse external factors stops.

Pathological tachycardia is a painful condition of the body. It develops at rest and can be either an independent disease or a symptom of many dangerous pathologies.

Classification of the disease depending on the location of the cardiac impulse generator

Depending on the location of the source of too frequent heartbeats, two types of tachycardia are distinguished: sinus and paroxysmal.

With sinus tachycardia, the so-called sinus node or pacemaker is activated. This formation is located in the wall of the right atrium, consists of conducting muscle fibers and coordinates the work of different parts of the heart.

With paroxysmal tachycardia, the source of the rapid heartbeat is in the atria or ventricles. It occurs in the form of attacks that have a sudden onset, a long course and an equally abrupt ending.

Causes of sinus tachycardia

In dogs, sinus tachycardia is most common. The reasons for it may be different. They are divided into intracardial (inside the heart) or extracardiac (their source is located outside the heart muscle).

The intracardiac form of pathology is usually caused by organic changes in various structures of the heart. They arise as a consequence of cardiomyopathy, myocarditis, cardiosclerosis, heart disease, pericarditis and other diseases of the heart muscle.

The extracardiac form can have different origins. It could be:

exposure to damaging factors (intoxication, infectious diseases, hypoxia);
influence of neurogenic factors (disorders of the autonomic nervous system, neuroses);
drug effects (reaction to medications - adrenaline, atropine, corticosteroids, diuretics and others);
other reasons (thyrotoxicosis, anemia, blood loss of various etiologies, pain syndrome).

Risk factors

Among the factors that provoke tachycardia are endocrinological problems, diseases of the cardiovascular and respiratory systems. Pregnant and lactating females suffering from endometriosis or mastitis may experience abnormal heart rates.

There are predisposed breeds that are more susceptible to the disease than other dogs. Large breeds include Great Danes, Alabais, St. Bernards, and Newfoundlands.

Small breed dogs often suffer from increased nervous excitability, which is the cause of heart disorders. These are Pekingese, Chihuahuas, Yorkshire terriers and others.

Service and hunting dogs whose lives involve heavy physical exertion and are full of stress are susceptible to tachycardia.

Dogs leading a passive lifestyle can also experience heart rhythm disturbances at the slightest exertion, since they are not at all accustomed to them.

Symptoms of the disease

Sinus tachycardia is characterized by a gradual increase in symptoms and their decrease, which is also extended over time. The dog may not feel significantly worse because the heart usually maintains normal sinus rhythm during the attack.

Paroxysmal tachycardia, on the contrary, begins and ends suddenly. The duration of an attack can range from one hour to several days.

The first symptoms of tachycardia in dogs are: rapid heartbeat, a feeling of heaviness or pain in the heart area. A severe degree of the disease is associated with insufficient blood supply to internal organs, including the brain.

With little physical activity, symptoms of oxygen starvation are observed: dizziness, loss of consciousness, feeling of lack of air.

Neurological signs (spasms and convulsions), as well as symptoms indicating the nature of the underlying disease, may occur.

Treatment of the disease

Treatment of tachycardia is aimed at eliminating the direct factors that cause its occurrence in dogs. Therapy is also carried out for the primary disease of which it is a symptom.

Physiological tachycardia does not need to be treated. After the irritating factors end their effect (physical rest occurs, the influence of stress is eliminated, high ambient temperatures cease to influence), the heart rate returns to normal.

For pathological tachycardia, the following methods can be used:

sedatives are prescribed (Corvalol, Valocordin, Potassium Bromide);
foci of infection are eliminated;
beta blockers and potassium supplements are prescribed (for the intracardial form of the disease);
antiarrhythmic drugs (Propafenone) are prescribed.
thyreostatic drugs are prescribed (for thyrotoxicosis).

During the course of treatment, you must follow the veterinarian’s recommendations: protect your pet from infections, do not expose your pet to excessive physical activity, and, if necessary, balance its diet. If the treatment is chosen correctly, the prognosis of the disease promises to be favorable.

The main measure for the prevention of arrhythmias and heart rate disorders is competent care and periodic medical examinations with the attending veterinarian with recording of a cardiogram. This is especially true for dogs whose breeds are most predisposed to the development of pathology.

Source: https://VeterinarGid.ru/dogs/bolezni/tahikardiya-u-sobak.html

The most common types of arrhythmias

Sinus tachycardia. Characterized by a significant increase in heart rate (more than per minute). The most common causes: pain, fever, anemia, decreased cardiac output, agitation. Consequences: there is too little time left for cardiac diastole (decreased filling of the heart with blood), decreased coronary blood flow. Sinus tachycardia at a rate of 250 beats/min after weeks leads to severe myocardial dysfunction and heart failure.

Sinus bradycardia. Slow heart rate (less than 60 beats/min). Causes: excessive parasympathetic activity (difficulty in breathing, irritation of the gastric mucosa, increased intracranial pressure), hypothyroidism, hypothermia, hyperkalemia, etc. May be accompanied by a persistent drop in blood pressure and a decrease in cardiac output.

Sinus arrhythmia. It occurs as a result of changing force of action (tone) of the vagal nerve. There is a clear connection with the phases of inhalation and exhalation. So, when you inhale, you can diagnose an acceleration of the heart rate, and when you exhale, a slowdown. Brachiocephalic breeds (pugs, bulldogs) are especially susceptible, since their breathing is accompanied by great effort. The atropine test is an important diagnostic criterion: with the administration of this drug, the arrhythmia disappears. Sinus arrhythmia is one of the harmless rhythm disturbances.

Atrial fibrillation. Supraventricular tachyarrhythmia, characterized by chaotic electrical activity of the atria. Prevents adequate contraction of the atria, most often associated with massive dilatation of the atria and wall deformation. The frequency of atrial contraction reaches . With this arrhythmia, the sinus node ceases to be a pacemaker; excitation occurs from multiple small foci localized over the entire surface of the atria. The frequency of ventricular contraction is determined by the conductivity of the atrioventricular node. The pathology is typical for dogs with dilated cardiomyopathy. It should be noted that in some giant breed dogs (for example, the Irish Wolfhound), rhythm disturbances can be diagnosed in the absence of changes in heart morphology.

Ventricular tachycardia. A life-threatening rhythm disorder for the dog. The development of ventricular tachycardia can result in the sudden death of the patient. Typical rhythm abnormalities in Boxers and Dobermans with dilated cardiomyopathy. In the first case, we observe right ventricular tachyarrhythmia, in the second – left ventricular tachyarrhythmia. Also, this rhythm disorder can occur in elderly patients and in patients without structural changes in the heart. It should not be confused with replacement idioventricular rhythm (the atrioventricular connection takes on the role of pacemaker). Characterized by a slower heart rate (less than 180 beats/min). It is a consequence of systemic diseases (acute gastric dilatation, pancreatitis, hemolytic anemia), and does not cause persistent hemodynamic disturbances. Disappears as the main problem is eliminated.

Extrasystole (premature contraction of the heart). An additional electrical impulse can occur in the atrium (supraventricular extrasystole), in the atrioventricular node, or in the ventricle (ventricular extrasystole). Occurs due to systemic diseases, electrolyte disorders of the blood or cardiac pathologies. Therapy for single extrasystoles is not indicated (does not affect cardiac hemodynamics or cardiac output). However, more careful monitoring should be carried out if fast ventricular extrasystoles, doublets (paired extrasystoles), and triplets occur. A transition to ventricular tachyarrhythmia is possible (boxers and Dobermans with dilated cardiomyopathy are especially susceptible).

Atrioventricular block. Slowing of impulse conduction through the atrioventricular connection. According to the severity, atrioventricular block is classified as 1st, 2nd and 3rd degree. Thus, grade 3 is characterized by complete dissociation of atrial and ventricular contractions and is a life-threatening arrhythmia. Therapy: installation of a pacemaker.

Sick sinus syndrome. Disruption of the normal functioning of the pacemaker. It is characterized by the appearance of hemodynamically significant pauses when the pacemaker stops generating impulses and the heart does not contract for several seconds. A pause of 8 seconds is accompanied by loss of consciousness. In some dogs, the pathology is characterized by a slow heartbeat (bradycardia); in other cases, sudden transitions from tachycardia to bradycardia are possible. It should be noted that most of the time the dog feels great, however, if episodes of rhythm disturbance are accompanied by loss of consciousness, installation of a pacemaker is indicated.

Heart problems in dogs may mean tachycardia

Tachycardia in dogs is a common heart pathology. This term means an increase in heart rate, and may indicate serious malfunctions in the four-legged pet’s body. In this article we will look at why tachycardia occurs in dogs, the symptoms and causes of this disease, we will find out how to treat the pathology, and how to prevent it.

Tachycardia is an increase in heart rate. Note that the normal heart rate in dogs for medium-sized dogs is 160 beats/min, and for large dogs – 140 beats/min. Small and dwarf dog varieties have a heart rate of 180 beats per minute, puppies - 220 beats per minute. If the indicators are increased according to the size and age of the dog, there is reason to talk about the presence of tachycardia in the dog.

This pathology indicates that the heart muscle is working too hard, which can lead to the “motor” wearing out too quickly. Also, as a result of ejecting less blood per contraction, the supply of nutrients and oxygen to cells deteriorates. But, although this type of disease occurs frequently, we are not talking about too serious complications here.

Everything becomes much more complicated when tachycardia occurs against the background of some infectious disease of the dog. The simultaneous development of these pathologies often leads to consequences such as myocarditis, pericarditis and endocarditis.

Causes

Tachycardia can be caused by both physiological and pathological reasons. The former are harmless, and tachycardia in this case occurs when the dog is very frightened or alarmed by something.

In addition, a physiological increase in heart rate often occurs in a male dog at the sight of a female, as well as in a hungry dog at the sight of food.

In this case, there is no need to worry about tachycardia: the heartbeat will return to normal on its own after some time without any consequences for the animal’s health.

Tachycardia caused by pathological causes is a much greater danger.

The symptom in this case is caused by the following factors:

febrile conditions;
interruptions in heart function;
impaired lung function;
various shock conditions;
the presence of congestion in the chest;
anemia of any origin;
infections, including sepsis;
low pressure;
dehydration;
oncology.

Sometimes an attack of tachycardia occurs due to a pulmonary thrombus. Unfortunately, they learn about this pathology only after an autopsy, since the death of the dog in this case occurs literally instantly. Note that dogs with a history of the following pathologies are at greatest risk of developing tachycardia:

In addition, tachycardia is especially dangerous for bitches, since during pregnancy and feeding puppies with milk, the disease can worsen and be complicated by mastitis and endometritis.

Sometimes tachycardia can also be caused by medications intended to relieve thyroid pathologies. The veterinarian usually warns about this property of some medications when prescribing them to an animal.

Literature

Santilli RA et al (2012) Orthodromic atrioventricular reciprocating tachycardia conducted with intraventricular conduction disturbance mimicking ventricular tachycardia in an English Bulldog. J Vet Cardiol 14(2):363–370
Nelson, RW & Guillermo Couto, C (1998) Small animal internal medicine. Mosby, Missouri. pp:22-23
Winter RL et al (2010) ECG of the month. Arrhythmogenic right ventricular cardiomyopathy in a Boxer. J Am Vet Med Assoc 236(9):961–963
Cruickshank J et al (2009) Genetic analysis of ventricular arrhythmia in young German Shepherd Dogs. J Vet Intern Med 23(2):264–270
Gelzer AR et al (2010) Combination therapy with mexiletine and sotalol suppresses inherited ventricular arrhythmias in German shepherd dogs better than mexiletine or sotalol monotherapy: a randomized cross-over study. J Vet Cardiol 12(2):93–106
Rodríguez-Morales O et al (2012) Plasmid DNA immunization with Trypanosoma cruzi genes induces cardiac and clinical protection against Chagas disease in the canine model. Vet Res 43(1):79
Ginn JA et al (2013) Systemic hypertension and hypertensive retinopathy following PPA overdose in a dog. J Am Anim Hosp Assoc 49(1):46–53
Matos J et al (2012) Myocardial damage and paroxysmal ventricular tachycardia in a dog after Albuterol intoxication. Schweiz Arch Tierheilkd 154(7):302–305
Kraus MS et al (2009) Toxicity in Doberman Pinchers with ventricular arrhythmias treated with amiodarone (1996-2005). J Vet Intern Med 23(1):1–6
Thompson DJ et al (2011) Haemangiosarcoma of the interventricular septum in a dog. N Z Vet J 59(6):332–336
Langs LL (2009) Budd-Chiari-like syndrome in a dog due to liver lobe entrapment within the falciform ligament. J Am Anim Hosp Assoc 45(5):253–256
Santilli RA et al (2009) Outflow tract segmental arrhythmogenic right ventricular cardiomyopathy in an English Bulldog. J Vet Cardiol 11(1):47–51
Santilli RA et al (2011) Ventricular tachycardia in English bulldogs with localized right ventricular outflow tract enlargement. J Small Anim Pract 52(11):574–580
MacKie BA et al (2010) Retrospective analysis of an implantable loop recorder for evaluation of syncope, collapse, or intermittent weakness in 23 dogs (2004-2008). J Vet Cardiol 12(1):25–33
Thomason JD et al (2008) Bradycardia-associated syncope in 7 Boxers with ventricular tachycardia (2002-2005). J Vet Intern Med 22(4):931–936
Wu W et al (2008) Application of quantitative tissue velocity imaging to evaluate left ventricular early diastolic dysfunction in dogs with heart failure due to rapid ventricular pacing. J Am Soc Echocardiogr 21(11):1269–1276
Santilli RA et al (2010) Evaluation of the diagnostic value of an implantable loop recorder in dogs with unexplained syncope. J Am Vet Med Assoc 236(1):78–82
Pariaut R et al (2011) Implantable cardioverter-defibrillator in a German shepherd dog with ventricular arrhythmias. J Vet Cardiol 13(3):203–210
Prosek R (2010) Electrical cardioversion of sustained ventricular tachycardia in three Boxers. J Am Vet Med Assoc 236(5):554–557