Blastomycosis is a fungal infection caused by the fungal organism Blastomyces dermatitidis (B. dermatitidis). The infection occurs in several regions of the world, including Europe, India and Central America, but in North America, most cases occur in the Ohio, Mississippi and Missouri River valleys. Cases have also been reported in other areas such as southern Canada and parts of the southern United States.
Blastomyces dermatitidis lives in soil. Although dogs can get infected through a skin wound that becomes contaminated by soil, most dogs get blastomycosis from inhaling B. dermatitidis fungal spores. Once inhaled, at body temperature, the spores become yeast and cause a fungal infection in the lungs that progresses to pneumonia. In some cases, the infection remains in the lungs, but in many other cases,B. dermatitidis uses the bloodstream to spread to other organs, such as the eyes, skin and bones. Less commonly, the infection can spread to the brain, heart, testicles and other parts of the body.
Blastomyces dermatitidis likes moisture, so the organism is more common near lakes, swamps and river banks. The organism does well in sandy, acidic soil; organic material such as decaying wood and animal feces also promote growth of B. dermatitidis, as does heavy rain. Recent construction or other activities that disturb the soil can increase the likelihood of spores getting into the air and being inhaled.
Blastomycosis is more common in dogs than in humans, and it’s rare in cats. Most affected dogs live near water, because that’s where the spores are likely to be found. The disease tends to affect young dogs, hunting dogs or outdoor working dogs, most likely from increased exposure to B. dermatitidis spores rather than from any genetic tendencies.
Because blastomycosis can affect so many regions of the body, clinical signs can vary depending on where the infection is. Signs of blastomycosis may include the following:
Results of routine blood tests, such as chemistry panel and complete blood cell count (CBC), are likely to be inconclusive, but they can help rule out other conditions. For dogs with respiratory problems, radiographs (X-rays) can be helpful. However, the lung changes caused by blastomycosis can resemble those of other types of pneumonia or even cancer. Similarly, radiographs of bones in affected dogs may show changes resembling bone cancer or bacterial bone infection. In these cases, your veterinarian may recommend submitting samples of lung or bone tissue to a diagnostic laboratory to confirm a suspected diagnosis of blastomycosis.
Currently, cytology is considered the most reliable way to diagnose blastomycosis. This may involve your veterinarian using a needle to take a small sample of cells from a lymph node, skin wound or other area of the body and submitting the sample to a diagnostic laboratory for examination. Although this is the preferred method of diagnosis, several samples may be required for confirmation.
Fungal culture testing can identify B. dermatitidis, so this can be helpful. Specific blood testing to look for antibodies to B. dermatitidis can also be performed, and there is also a urine test that can diagnose the condition in approximately 90 percent of infected dogs. Your veterinarian will discuss the best diagnostic options for your pet.
Dogs with severe pneumonia may require hospitalization for oxygen therapy and intensive nursing care. Dogs who are not severely ill can usually be treated at home. Anti-fungal medication successfully treats the infection in over 75 percent of dogs. However, most dogs require treatment for several months.
Because recovery takes a long time, many veterinarians recommend monitoring pets during treatment to assess response to medication. Some veterinarians use the urine test to monitor response to treatment. For dogs with pneumonia, your veterinarian may recommend periodically repeating chest radiographs to see if the lung abnormalities are improving.
Over 75 percent of dogs respond to treatment for blastomycosis, so the likelihood of recovery is good. Dogs with brain disease or severe pneumonia are less likely to survive. Also, some dogs with pneumonia die during the first week or so of treatment as the result of an inflammatory reaction initiated by the death of the B. dermatitidis organisms in the lungs. Some dogs who recover develop permanent scar tissue in their lungs.
For dogs who survive the initial infection, approximately 20 percent relapse within the first several months to years following infection. In 80 percent of those cases, a repeat course of treatment is successful.
Research suggests that some dogs contract blastomycosis but don’t develop clinical signs and get better without treatment. However, dogs who do develop signs of illness should receive aggressive treatment as recommended by a veterinarian.
Blastomycosis is not contagious, so humans can’t catch it from a sick dog, and it can’t be spread from one dog to another. However, humans can be exposed through inhalation of spores just like dogs can. So walking a dog in an area where spores may be present increases the risk for human exposure. Pet owners are advised to notify their physicians if they develop skin or respiratory abnormalities and their dog has been diagnosed with blastomycosis.
Studies have shown that humans can also become infected through skin wounds if exposure to contaminated soil occurs. Humans are also advised to avoid being bitten by infected dogs.
There is currently no vaccine to protect dogs from blastomycosis, but research to develop one is ongoing. Preventing exposure to areas where the organism lives can reduce risk of blastomycosis, but this may be impractical, especially for dogs who live near these areas.
Heart murmurs are detected when a veterinarian listens to a dog’s heart and hears a whooshing sound. It’s not always a reason for concern, but it can be. In dogs, common causes include heart valve problems, heartworm disease, heart defects, tumors, or weakening of the heart muscle. If your dog has difficulty breathing, sounds congested or coughs, has a pot belly, faints, or suddenly collapses, he could have a heart condition. Treatments can include surgery or addressing any underlying issues that may be causing the murmur.
A heart murmur is an abnormal sound that a veterinarian hears when listening to a dog’s heart through a stethoscope. Normally, a veterinarian hears two sounds, a “lub” and a “dub,” which are the sounds of the heart valves closing as blood circulates through the heart. An additional “whooshing” sound or other noise, known as a heart murmur, is usually associated with a disturbance of the normally smooth flow of blood through the heart.
Veterinarians rank the intensity or loudness of a heart murmur in grades from one to six, with one being barely audible and six being the loudest. There is also a one-to-five ranking system that works the same way. These grades do not necessarily correlate with the severity of the heart condition; they are merely one of several ways that veterinarians attempt to characterize the the murmur.
Though it’s not considered normal, a heart murmur is not always a cause for concern. It may, however, be an indication of a heart problem. Depending on your dog’s condition, the veterinarian may want to perform additional diagnostic tests to determine the cause of the murmur.
Heart murmurs are caused by any number of conditions that can create turbulence in the flow of blood through the heart. In dogs, common causes for heart murmurs include:
Occasionally, a veterinarian detects a heart murmur in a young puppy. Though this may indicate the presence of a congenital heart condition (a defect the puppy was born with), in many cases it is what is called an innocent murmur, meaning that it is not related to a heart problem. These murmurs usually disappear by the time the animal is about 4 months of age. If a murmur does not resolve, your veterinarian may recommend diagnostic testing to investigate it further.
Not all dogs with a heart condition show outward signs. However, if you have been told that your dog has a heart murmur, you should watch for signs such as:
If your dog displays any of these signs, call your veterinarian for advice or to schedule an exam.
To determine the cause of a heart murmur, your veterinarian may recommend a number of tests, such as:
Treatment depends on the cause of the heart murmur and your dog’s condition. If your dog is not showing any signs of heart disease other than the murmur, your veterinarian may prefer to monitor your dog and provide treatment only if signs occur.
In some cases, such as when a heart murmur is caused by heartworm disease, treatment may resolve the heart murmur completely. If the murmur is caused by a congenital condition, surgery may be recommended. In other cases, the heart murmur may remain, but medications can help make your dog more comfortable and improve your pet’s longevity.
Cardiomyopathy, which literally means disease of the heart muscle, can strike both dogs and cats in different ways. Symptoms are varied, ranging from collapse and weakness to difficulty breathing and sudden death. Fortunately, veterinarians are often able to diagnose the disease before symptoms occur and may be able to prescribe drugs to keep symptoms in check.
Cardiomyopathy refers to any disease that affects the heart muscle. Diseases of this type fall into one of three major categories: dilated cardiomyopathy, hypertrophic cardiomyopathy, and restrictive cardiomyopathy. All of them are considered idiopathic, meaning the exact cause is not fully understood.
Dilated cardiomyopathy is characterized by the cardiac muscle’s inability to contract properly. Decreased contractility means that the heart cannot pump blood adequately, which leads to poor circulation and other complications including irregular heart rate and heart failure.
Dilated cardiomyopathy is the most common kind of cardiomyopathy observed in dogs. It is fairly widespread among certain breeds and presumed to be hereditary. Large-breed dogs are most likely to acquire the condition and generally do so during or after middle age.
Cats may develop dilated cardiomyopathy also, generally caused by a nutritional deficiency in the amino acid taurine, which leads to an inability to support normal cardiac muscle function. However the most common type of cardiomyopathy in cats is an inherited disease called hypertrophic cardiomyopathy. The exact way the disease occurs in cats is unknown, but the result is that the heart muscle becomes extremely thickened with normal and abnormal cells. The thickened muscle can’t relax and contract normally, which decreases the amount of blood that the heart can handle. Heart failure results because there is so little room for blood to collect and be pumped out to the rest of the body. Because certain breeds of cats are more often affected (some as young as 3 months and others as old as 17 years, but generally around middle age), it is assumed to be hereditary.
Restrictive cardiomyopathy is relatively rare and poorly understood. With this condition, the cat’s heart muscle begins “filling in,” encroaching on the heart’s four chambers and limiting blood output, usually severely.
The symptoms of cardiomyopathy can vary. In some cases of dilated cardiomyopathy, the disease is characterized by collapse, weakness, and, occasionally, by sudden death. These events are usually the result of changes in electrical conduction in the heart muscle. Some affected dogs may live long enough to suffer from congestive heart failure, for which coughing and difficulty breathing are the most typical signs.
In other cases, sudden death and collapse may not occur. Instead, heart failure with fluid buildup in the abdomen (ascites), weakness, exercise intolerance, and fluid in the chest cavity or lungs are the most common signs.
In cats, hypertrophic cardiomyopathy can prove completely asymptomatic (meaning no outward signs of disease are observed). Alternatively, it can lead to collapse or difficulty breathing, life-threatening blood clots, or sudden death (for animals who suffer unexpected, devastating electrical disturbances to their heart rhythms).
Veterinarians can often identify cardiomypathy before signs occur. A heart murmur (abnormal sounds in-between heart beats) may be detected, though in many cases, animals won’t develop one before succumbing to the disease.
Diagnosis is typically achieved with X-rays (demonstrating marked enlargement of the heart); EKGs (electrocardiograms, which may or may not show electrical disturbances in the heart); and, most effectively, via cardiac ultrasonography (echocardiograms), in order to characterize the physical changes in the heart muscle.
Among cats, Maine Coons, Persians, and American Shorthairs are predisposed to hypertrophic cardiomyopathy, though all cats are potentially at risk.
In dogs, Boxers, Doberman Pinschers, Newfoundlands, Great Danes, German Shepherds, Irish Wolfhounds, Scottish Deerhounds, Saint Bernards, Labrador Retrievers, American Cocker Spaniels, Springer Spaniels, Cavalier King Charles Spaniels, and English Cocker Spaniels are more commonly affected.
Treatment usually involves administering medication to control the clinical signs of congestive heart failure and cardiac enlargement while increasing the ability of the heart muscle to contract. For cats, an additional goal is to reduce the possibility of blood clot formation.
Feeding cats a nutritionally complete diet can reduce their risk of developing dilated cardiomyopathy associated with taurine deficiency. However, most types of cardiomyopathy in dogs and cats are likely hereditary, so removing affected pets from the breeding pool is recommended.
Pulmonary edema is an accumulation of fluid in the lungs. It happens to both pets and people and can have a variety of causes including heart failure, cancer, or a traumatic event such as electrocution or a head injury. Symptoms can include coughing, difficulty breathing, blue lips, and collapse. In most cases, medication can resolve pulmonary edema, but the long-term outcome really depends on the underlying cause.
Most lung tissue is made up of tiny clusters of air balloons called alveoli. Each air balloon is lined by a thin layer of cells in contact with very small blood vessels. When you breathe, air fills the alveoli. Once filled with air, the cells lining the alveoli and the small vessels next to them then take in oxygen from inhaled air and release carbon dioxide into the exhaled air.
When alveoli become filled with fluid instead of air, the space that is normally available for oxygen uptake and carbon dioxide elimination becomes limited. We call this condition pulmonary edema. Edema is a very general term that refers to fluid accumulation anywhere in the body; pulmonary edema refers specifically to fluid accumulation within the lungs.
Generally, the fluid that accumulates in the alveoli comes from surrounding blood vessels and tissues that have been affected by one of many disease processes so that they leak into the lungs.
Pulmonary edema can have many causes. Some types of trauma (such as strangulation, electrocution, or severe head injury) can result in pulmonary edema. The condition can also be associated with diseases such as heart failure and cancer.
Depending on how much fluid has accumulated in the lungs, the clinical signs of pulmonary edema can be very mild or severe and may include:
Because many medical conditions can cause pulmonary edema, some clinical signs may be associated with the underlying cause of the edema. For example, other injuries may be associated with a traumatic event that caused pulmonary edema.
Obtaining a medical history and performing a physical examination are the first steps in diagnosing pulmonary edema. When your veterinarian examines your pet, he will listen to your pet’s chest with a stethoscope to determine whether the air moving into and out of the lungs and airways sound normal. Your veterinarian will also use the stethoscope to check your pet’s heart for murmurs (abnormal noises between heartbeats) or changes in rhythm and heart rate.
Many veterinarians use chest radiographs (X-rays) to confirm a diagnosis of pulmonary edema. Once pulmonary edema is diagnosed, your veterinarian may recommend additional testing to determine the nature of the fluid and look into possible underlying causes for the edema.
Treatment for pulmonary edema can involve several goals:
Stabilize the patient. If the patient is having significant trouble breathing or is otherwise unstable, oxygen therapy and other treatments may be necessary to stabilize the pet. Because pulmonary edema can set the stage for the development of pneumonia, antibiotics are sometimes given along with other treatments.
Treat the edema. In most cases, medications can be administered to resolve the edema. If the fluid accumulation is severe, hospitalization may be recommended so that the patient can be supported and monitored as treatment is progressing. Your veterinarian may recommend repeating chest X-rays periodically to monitor how well the edema is resolving.
Address underlying illnesses. The underlying cause for the pulmonary edema (for example, heart failure) may need to be managed with additional medications, monitoring, and follow-up diagnostic testing.
The outcome for a pet with pulmonary edema will depend heavily on the cause of the edema. For example, if a pet has heart failure, the edema may return unless the heart failure is treated effectively. In this case, heart failure is a chronic illness, so there is always a chance that the pulmonary edema can return. In contrast, if pulmonary edema results from a traumatic event (such as a head injury or strangulation), it can be treated definitively as long as the patient recovers from the inciting trauma.
Tricuspid valve dysplasia is caused by a congenital birth defect (meaning it is present before or at birth) that results in a heart valve that is abnormally shaped. The condition is most common in large-breed, male dogs but may occur in cats, as well. A heart murmur may be an early warning sign. Affected animals may also experience a bloated, fluid-filled belly; weakness; exercise intolerance; and difficulty breathing. Treatment may include a low-sodium diet, exercise restriction, and drugs to help the heart beat more efficiently, as well as medications to treat fluid retention. In severe cases, surgical replacement of the valve may be recommended.
Some background: The heart muscle is a pump that moves blood through the four chambers with involuntary contractions that promote the one-directional flow of the blood. The valves between the chambers prevent the backflow of blood into the preceding chamber, thus keeping the blood moving in the direction it should. When the valves are misshapen or otherwise poorly formed, some blood can move backward, not forward, in the heart. This means the heart has to work harder to pump the volume of blood the body needs for normal functions.
When the tricuspid valve, which is between the right atrium and right ventricle, fails to form a tight seal, the blood pumped from the atrium into the ventricle is regurgitated into the atrium. The degree of dysplasia will determine how much blood moves the wrong way and, hence, the severity of signs.
Large-breed dogs are most commonly afflicted, with male dogs overrepresented.
Dogs may be diagnosed with a heart murmur before the onset of any signs of tricuspid valve dysplasia. If the murmur is progressive or significant, veterinarians will recommend radiographs (X-rays), EKGs (electrocardiograms), and echocardiograms (heart ultrasounds).
X-rays may show an enlarged right side of the heart, while the EKG may reveal abnormal heart rhythms caused by this enlargement. The best tool, however, is the echocardiogram. This kind of imaging tool visualizes the abnormal shape of the valve and the degree of blood regurgitation that is occurring.
The most common signs of tricuspid valve dysplasia are related to the disorder veterinarians call right-sided heart failure. With this condition, dogs will have distended abdomens due to the fluid accumulation (ascites) that occurs when the blood backs up on its way back to the heart. They may also experience exercise intolerance and difficulty breathing if they’re unable to get enough oxygen into their blood as a result of the poor volume of blood reaching their lungs (blood from the right side of the heart flows into the lungs to receive oxygen).
Occasionally, life-threatening abnormal heart rhythms may result. These can lead to sudden death.
Larger-breed dogs are predisposed to this hereditary disease, especially the German Shepherd, Golden Retriever, Great Dane, Labrador Retriever, and Weimaraner.
In most cases, treatment is aimed at easing the signs of the disease, rather than repairing the valve. Treatment may include low-sodium diets, exercise restriction, and medications to help the heart pump more efficiently and remove excess fluid from the body. In severe cases that don’t respond to medical management, surgical replacement of the valve may be recommended.
Affected dogs should be removed from the breeding pool. Since very mild forms of the disease may be undetected through conventional means, screening dogs within highly affected breeds (with echocardiography) prior to breeding may be helpful.
Sick sinus syndrome has nothing to do with the respiratory system, as one might think. It is a serious cardiac condition that causes abnormal heart rhythms in dogs. It is unclear what is behind the disease, but signs are weakness, fainting, seizures, and even death. There are drugs to help mildly affected patients, but a pacemaker is really the best treatment for symptomatic dogs.
Sick sinus syndrome is a cardiac condition of unknown cause that affects the heart rate and rhythm of both humans and dogs. In this disease, the heart’s electrical impulse-generating sites (called sinuses) fail to function normally. As a result, dogs with this problem are unable to maintain normal heart rhythms, and many also suffer other changes in heart rate.
This disease will vary in severity among dogs, with some suffering catastrophic failure to pump blood (when the heart rhythm is severely disturbed) and others living perfectly normal lives.
For more severely affected dogs, the syndrome can be divided into two classes of patients based on their abnormal heart rhythms: those for whom the rhythm varies from slow to fast (bradycardia-tachycardia) and those in which the rhythm is characterized by slowness and occasional stopping (bradycardia and sinus arrest).
A low heart rate (or another abnormal rhythm) is the most common finding, but some dogs will be diagnosed only after they’ve collapsed or fainted (known as a syncopal episode) or had a seizure. Episodic weakness is also commonly associated with sick sinus syndrome. Sudden death is always a risk with these patients.
Diagnosing the disease is typically achieved via EKG (ECG or electrocardiogram) and/or a Holter monitor (a device the dog wears for continuous EKG monitoring of the heart rhythm). An echocardiogram (heart ultrasound) is also a necessary step to rule out underlying or concurrent cardiac disease. A trial with a drug that speeds up the heart (atropine) may also be employed in a controlled setting.
Your veterinarian may recommend that you see a veterinary cardiologist for diagnosing or treating this disease.
Sick sinus syndrome has been identified in older female Miniature Schnauzers, Dachshunds, Cocker Spaniels, West Highland White Terriers, and Pugs, though other breeds have occasionally been diagnosed with it as well. This disesase rarely occurs in cats.
Some dogs who experience signs of sick sinus syndrome are candidates for treatment. Others may not necessitate any treatment whatsoever. In both cases, it’s a good idea to avoid strenuous exercise and stressful situations. Drug therapy may be employed for mildly affected patients, but a pacemaker is considered best for symptomatic dogs.
Veterinarians do not know the mode of inheritance, and genetic tests are not available. Affected dogs and their parents and siblings should not be bred.
Pets are like a breath of fresh air on a stifling hot day. But when a pet can’t get a breath of fresh air? That’s what happens with a tracheal collapse, and it’s a genetic condition that runs in the lines of little dogs. The biggest tip-off of the disorder is that a dog coughs when he gets very excited or while playing or exercising. Mild cases can be left alone; medications to keep a dog calm or limit the sensitivity of the trachea can be prescribed in more serious cases. In especially severe situations, surgery may provide relief.
Tracheal collapse, also referred to as collapsing trachea, is a common disorder of the windpipe in dogs. It’s an inherited disorder in which the trachea’s normally firm cartilage rings of support are softer and less supportive than they should be. In these cases, inhaling air during the normal act of breathing can cause the trachea to collapse on itself (much like a flimsy straw would with a thick milkshake), which typically elicits a hacking cough. This happens most often with excitement and/or exercise. The inflammation that results in tracheas thus affected can mean chronic discomfort for the (typically tiny) dogs affected.
The mode of inheritance of this disorder has not been worked out.
Observing a characteristic hacking or honking cough that occurs with excitement or exercise is the most common way milder forms of this disease are diagnosed. Middle-aged to older dogs are more often affected.
With more severe cases, simple X-rays or more sophisticated measures like fluoroscopy (akin to a real-time, moving X-ray) are used to determine the extent of the narrowing of the airway. A scope to visualize the airway directly is often recommended. (This procedure requires anesthesia.)
Ensuring no underlying cardiac disease is present is a basic approach as well. That’s why echocardiography, an ultrasound of the heart, may be undertaken in some cases.
Miniature, toy, and teacup dogs are most often affected. The Yorkshire Terrier, Pomeranian, and Toy Poodle are overrepresented among afflicted breeds.
Treatment for mild cases is not always necessary. Though some training to reduce excessive excitement (which elicits symptoms) can be very effective, this step is not considered mandatory to help dogs maintain an excellent quality of life.
For moderate to severe cases, the administration of medications that reduce excitement and/or limit the sensitivity of the trachea can be helpful. Sedatives, bronchodilators, nebulization (or vaporization), and the occasional implementation of corticosteroids to address the inflammation of the trachea are typical approaches. For the most severe cases, surgery may be recommended.
All affected dogs should wear harnesses, not collars, to limit external pressure on their tracheas.
Limiting the inheritance of this trait has proven difficult, as the disease often doesn’t make itself known until later in life –– well after animals have been bred.
Bordetella bronchiseptica is an easily contracted bacteria that causes a hacking cough or, occasionally, a snotty nose. Any pet can get the disease, and except in severe cases, a round of antibiotics is usually all that’s needed to treat it. In fact, many cases are mild and self-limiting enough that they require no treatment whatsoever. Vaccination can protect your dog from illness associated with Bordetella.
Bordetella bronchiseptica is a bacterium that is commonly associated with respiratory disease in dogs. It can also infect cats, rabbits, and, in rare cases, humans. It is one of the more common bacterial causes of canine infectious tracheobronchitis — also known as kennel cough.
Bordetella bronchiseptica is one of several organisms included on a short list of bacteria and viruses responsible for this kennel cough syndrome. Bordetella is highly contagious, easily transmitted through the air or direct contact, and resistant to destruction in the environment.
In healthy adult dogs, Bordetella usually causes no more than a mild, self-limiting illness. In puppies or in dogs with other underlying health issues, however, it can cause severe illness (such as pneumonia) or even death in rare cases.
Signs of kennel cough typically develop two to 14 days after exposure. In mild cases, signs may resolve within 10 to 14 days. More severe cases, particularly when a subsequent infection has occurred, can require a much longer recovery.
A persistent honking, hacking, and/or gagging cough is typical of Bordetella infection. Many owners describe the cough as “vomiting” or believe something is stuck in their dogs’ throats. In these cases, this presentation is merely an uncomfortable symptom of an inflamed trachea.
Fever and lethargy (tiredness) may also occur. Sometimes, a whitish or greenish nasal discharge is also observed, but in other cases, clinical signs may be absent or so mild that they go unnoticed.
Although sophisticated testing is available, diagnosis is generally based on a history of exposure to infected dogs or a recent visit to a kennel, combined with the presence of signs of illness.
All breeds of dogs are equally susceptible to Bordetella.
In mild infections, treatment is generally supportive because the disease can resolve on its own unless a secondary (subsequent) infection occurs. Precautionary antibiotics to prevent secondary infection may be prescribed. In severe cases, treatment may consist of administration of antibiotics, cough suppressants, and inhalant medications to help patients breathe more easily. When possible, a harness, rather than a collar, is recommended for leash walking of ill dogs. A traditional collar puts pressure on already sensitive and irritated tracheal tissues and can induce coughing episodes.
“Kennel cough” might well be a misnomer. That’s because dogs don’t necessarily contract the disease just from being kenneled. Rather, they become ill because kennels can be stressful environments and stress can suppress the immune system, increasing susceptibility to disease. Typical kennel conditions (such as group housing) can make it easier to spread infectious organisms, such as Bordetella bronchiseptica.
Vaccination can protect your dog from illness associated with Bordetella, particularly if your dog frequents kennels, groomers, dog shows, or dog sporting events. To reduce the risk of disease transmission, many boarding facilities and grooming salons require dogs to be vaccinated against kennel cough before entry.
Although the B. bronchiseptica vaccination is not mandatory for every dog, it may be recommended in dogs whose lifestyle increases their risk of exposure to this organism. An intranasal vaccine is available in addition to the traditional injectable vaccine. Your veterinarian can tell you whether vaccination is recommended for your pet and, if so, which type is best for your pet.
When the heart can’t deliver enough blood to the body and fluid consequently backs up into a dog’s lungs or abdomen, it’s called congestive heart failure. There are many causes of congestive heart failure (CHF) in dogs. CHF can be brought on by high blood pressure, congenital heart defects, heartworm disease, or a variety of other disorders. A dog with congestive heart failure may cough, have trouble breathing, experience fatigue, loss of appetite, or might die suddenly. Depending on the underlying cause, treatment can help reverse congestive heart failure, and medications are available to help relieve its symptoms.
Congestive heart failure is a broad medical term that means that a dog’s heart can’t deliver enough blood to his or her body. It can be caused by a failure of the left side, right side, or both sides of the heart.
When the heart starts to fail in its ability to pump enough blood, the body can usually compensate to ensure that tissues receive the blood and oxygen they need. As the disease increases in severity, these compensatory mechanisms become overwhelmed. The heart is then unable to pump enough blood to the body, so fluid backs up, most often into the lungs, causing congestion –– hence the term congestive heart failure.
Though many conditions can lead to congestive heart failure in dogs, one of the more common causes is chronic valve disease. When valves of the heart degenerate they may fail to function properly, leading to an increased burden on the heart and eventual CHF. Dilated cardiomyopathy is also a frequently observed cause of CHF in certain breeds of dogs. In this condition, the chambers of the heart become enlarged, which weakens the muscle walls so that they are unable to pump adequate amounts of blood to the body.
As a result of either disease, fluid may back up into the lungs, making breathing difficult, or into the abdomen, giving the dog a pot-bellied appearance.
Other causes of congestive heart failure in dogs include:
Congestive heart failure can occur at any age, in any breed, or in dogs of any gender, but it happens most often in middle-aged to older dogs.
In the early stages of congestive heart failure, your dog may show no signs at all. As the disease progresses, signs may include:
Congestive heart failure is usually diagnosed based on symptoms and physical examination findings, in which fluid in the lungs causes them to sound congested when your veterinarian listens with a stethoscope. To definitively diagnose the condition and determine its cause, veterinarians will usually recommend a number of tests, such as:
Referral to a veterinary cardiologist may be recommended.
All dog breeds may be affected by congestive heart failure, but Boxers, Doberman Pinschers, and Cocker Spaniels may be genetically predisposed to certain types of heart failure.
In some cases, such as congestive heart failure that is caused by heartworm disease, treatment of the underlying condition may resolve some or all of the heart problems. If the problem is caused by a congenital condition (a heart defect that the dog has had since birth), surgical repair may be an option. In most cases, however, the problem cannot be cured, but treatment can help improve dogs’ quality and length of life.
Dogs with severe congestive heart failure may require initial hospitalization and oxygen therapy. There are many medications that veterinarians may recommend to help reduce fluid buildup, improve heart function, and/or normalize heart rhythms. A low-sodium diet may also be recommended to help minimize fluid accumulation.
Most dogs with congestive heart failure require medications for the remainder of their lives. Periodic blood tests, radiographs, and echocardiograms are often needed to monitor treatment success and disease progression.
There is no known means of prevention of canine congestive heart failure except through judicious breeding programs designed to eliminate any hereditarily affected animals from the gene pool.
Ventricular septal defect (VSD) is a hole in the heart left when the organ doesn’t form properly in utero. This birth defect affects many breeds of dogs and causes one side of the heart to work harder than the other. A dog with severe VSD will be exercise intolerant and short of breath — and could even collapse and die. Treatment ranges from medications to surgery.
In the mammalian embryo, the heart develops as a tube that separates into the four chambers that make up the pumping mechanism for the body’s blood (the right and left atria and right and left ventricles). With a VSD, the wall (or septum) between the two ventricles fails to fuse normally, leaving a hole in the heart’s inner wall.
Because blood needs to move in one direction through the heart, the presence of this defect means that some of the blood that enters the left side of the heart (after receiving oxygen from the lungs) gets shunted back to the right side of the heart instead of out to the rest of the body, as it’s meant to be. Ultimately, this defect means that the left side of the heart has to work harder to pump the amount of blood the body requires for normal functions — and that by doing so it might break down under the weight of this overload.
This disease is congenital (meaning puppies are born with it), but it occurs sporadically in several breeds, so there is some discussion among researchers about whether it is truly “genetic” or merely a failure of normal embryo development. The condition also varies in severity depending on the size and location of the hole between the two ventricles and whether there are any other defects involving the heart.
Some puppies have so small a defect in the wall between the ventricles that it spontaneously closes relatively early in life. These pups will not show symptoms, though they’ll typically have a heart murmur until the abnormal opening closes.
Others will suffer severe VSD, in which case a veterinarian can detect a heart murmur early on, though symptoms may not develop until later in life.
The most common symptoms are the result of the left side of the heart’s work overload. This will cause an enlargement of this side of the heart and clinical signs including shortness of breath, coughing, exercise intolerance, sudden death, or, less commonly, cyanosis (blue tinged discoloration of the gums, lips, or tongue as a result of inadequate oxygen supply).
Diagnosis of VSD is achieved through X-rays to see the enlargement of the heart, EKG (electrocardiogram) to pick up electrical changes as a result of the enlargement, and, most crucially, an echocardiogram (heart ultrasound) equipped with Doppler technology to identify the defect in the ventricular wall and the abnormal flow of blood there.
Unfortunately, VSD affects many breeds sporadically, and its method of inheritance has not been fully determined.
Drugs are the primary approach for dogs who show symptoms (remember, some may not). For more severe cases, however, drugs may be insufficiently effective.
In cases for which drug therapy is insufficiently effective, surgical options are available. However, surgery is relatively costly and generally available only at specialty referral centers.
Exercise restriction, a low-sodium diet, and weight management may be recommended for symptomatic VSD patients.
Preventing VSD requires removing affected dogs from the breeding pool.
Should your neighbor’s barking dog get laryngitis, you might be forgiven for thinking it’s a blessing. But laryngeal paralysis is something else altogether. The condition, which primarily affects dogs (rarely cats), occurs when the larynx closes when it should open. Difficulty breathing and collapsing during exercise can occur, as well as noisy breathing and gagging. Laryngeal paralysis is a genetic condition for some dog breeds, though it may be caused by disease in others. Treatment ranges from exercise restriction and/or medication in mild cases to surgery in serious cases.
The larynx is the structure at the back of the throat (at the entrance to the trachea) that opens to allow airflow in and out of the trachea and lungs. It also closes to prevent the entry of food and liquids into the lungs during swallowing. Also known as the voice box, the larynx enables dogs to bark and howl.
Laryngeal paralysis is a condition in which the cartilage and vocal folds of the larynx are unable to open fully during breathing, making inhalation especially difficult.
The condition can be inherited in some breeds, such as Bouvier des Flandres, Siberian Huskies, and Dalmatians. In these cases, the condition usually occurs within the first 6 months of life. More often, laryngeal paralysis occurs in large-breed dogs later in Iife. St. Bernards, Newfoundlands, Labrador Retrievers, Golden Retrievers, and Irish Setters are often affected. Laryngeal paralysis rarely occurs in cats.
Dogs with laryngeal paralysis generally experience signs related to breathing and barking. A hoarse, raspy, roaring sound that is most audible upon inhalation is typical. Sometimes, difficulty breathing and collapse (most common during exercise, especially in hot weather) can also occur, as well as gagging and hacking while eating or drinking. The bark may also become hoarse or raspy.
The best way to diagnose laryngeal paralysis is to observe the larynx while the dog is under sedation or anesthesia. Usually, the veterinarian will notice that one or both sides of the larynx do not open normally when the dog inhales. Other diagnostic tests may be recommended to determine if there are underlying diseases or complications that can occur as a result of laryngeal paralysis.
For the Dalmatian, Bouvier des Flandres, Siberian Husky, and some other breeds, the disease can be inherited. In other cases, the cause is unknown or can result from other diseases affecting the nerves and muscles controlling the larynx.
Treatment of laryngeal paralysis depends greatly on how severely a dog is affected. In very mild cases, no treatment may be indicated, apart from exercise restriction and stress avoidance. Sometimes, mild sedatives or anti-inflammatory medications are prescribed. However, in more severe cases that present with acute respiratory distress, dogs may require oxygen therapy, hospitalization, and intensive care management of the condition until the crisis resolves.
Definitive treatment for severe cases involves surgery. A common procedure is to use suture material to tie back one side of the cartilage, creating a larger opening for air movement. Though this surgery makes it possible for dogs to breathe more normally, an unfortunate potential side effect involves the accidental inhalation (aspiration) of food and/or water and the possibility of pneumonia.
For dogs with laryngeal paralysis, episodes can be minimized by reducing stress and exertion, and providing medication when necessary. Dogs with the inherited form of the disease should not be used for breeding.
Pets are like a breath of fresh air on a stifling hot day. But for pets with brachycephalic syndrome, a condition suffered by many dogs and cats with pushed-in faces, getting a breath of fresh air isn’t always easy. The biggest tip-off to the disorder is noisy breathing (e.g., the Pug who snores while he is awake). Snuffling, gagging, exercise intolerance, and tummy troubles are also clues. Many cases are left untreated and, with a proper lifestyle, have no problems. But for some pets, surgery to improve airflow is recommended.
Brachycephalic syndrome, also referred to as brachycephalic airway obstructive syndrome (BAOS), is the term applied to the diseased upper respiratory system common to brachycephalic dogs. This includes Bulldogs and other breeds for which a shortened head is a standard trait.
The structures most notably affected include the fleshy soft palate, which is often overlong (elongated soft palate) and may droop to obstruct the opening of the larynx; the nostrils, which are often too small and narrow (stenotic nares); the larynx, where swollen folds hinder normal air movement (everted laryngeal saccules); and the trachea, which may be too small to accommodate the amount of air required by affected pets (hypoplastic trachea).
Noisy breathing is typical of affected animals. Snoring, snuffling, coughing, gagging, and chronic raspiness are signs. Moderate to severe heat intolerance is typical, and heat stroke, fainting, or collapse can occur should owners not abide their pets’ inherent respiratory limitations (such as when taking them for too-long walks or out on hot days). Exercise intolerance and cyanosis (visible as blue-tinged gums and tongue) can also occur, due to their inability to breathe effectively.
Gastrointestinal issues are fairly common for these pets, too. Dogs that gulp air in the process of attempting to eat may belch, gag, regurgitate, and/or vomit frequently. Accidental inhalation of food material into the lungs and resulting infection in the lungs (aspiration pneumonia) is not uncommon in these cases.
Diagnosis is achieved by observing the clinical signs and directly visualizing the affected structures to assess the degree of abnormality. Determining the severity of disease is a necessary step toward deciding what type of treatment is most appropriate.
Among dogs, the disease is typically most severe in the English Bulldog. Others include the Pug, Boston Terrier, Pekingese, French Bulldog, Cavalier King Charles Spaniel, Chinese Shar-Pei, Lhasa Apso, and Shih Tzu. However, any brachycephalic dog can develop this condition.
Among cats, the Persian is most affected. Himalayans and Ragdolls can also be afflicted.
Treatment of brachycephalic syndrome is aimed at removing the airway obstruction where possible. In the case of hypoplastic trachea, there is very little that can be definitively achieved surgically. However, stenotic nares, elongated soft palates, and everted laryngeal saccules can all be treated surgically.
Cases that are less severe can frequently be managed through limiting exertion, limiting exposure to heat and humidity, and prescribing medication to alleviate clinical signs when appropriate.
Persistent right aortic arch is a congenital abnormality of the blood vessels of the heart that can affect esophageal function in some dogs and less commonly, in cats. Basically, an embryonic branch of the aorta fails to regress and is wrapped around the esophagus when a puppy or kitten is born. This puts pressure on the tube, preventing the passage of food in the esophagus when the pet eats, causing regurgitation. Surgery can correct the problem, and follow-up care can usually reverse the esophageal effects, especially if done early in a pet’s life.
The vascular condition known as persistent right aortic arch is also called vascular ring anomaly or vascular compression of the esophagus. It’s a condition that results from the abnormal development of the artery that arises directly from the heart, the aorta.
In the uterus, the fetus has right and left aortic arches, which rise up from the heart, then curve down to supply blood to the abdomen and beyond. During normal development, the left aortic arch remains as the main artery, while the right aortic arch regresses. If, however, the right aortic arch persists instead of, or in addition to, the left aortic arch, it can wrap around and constrict the esophagus. While it doesn’t cause a problem to the cardiovascular system itself (i.e., blood flows without impediment), the constriction of vital structures like the esophagus (the tube that carries food into the stomach) and occasionally the trachea (windpipe) can be devastating to the affected pup.
The consequence of this abnormal ring around the body’s feeding tube is often regurgitation due to a compressed esophagus. Aspiration pneumonia can also result when dogs inhale the food they’re meant to ingest.
Symptoms of a persistent right aortic arch become apparent once a pup starts to eat solid foods. Though milk will slide down nicely, bulky foods will jam up in the esophagus, leading to a stretched structure and the inability to get food down –– hence the regurgitation.
A stretched (dilated) esophagus, sometimes termed megaesophagus, is a typical result of the physical obstruction provided by a persistent right aortic arch. Stunted growth (due to lack of nutrition) and breathing problems (often the result of aspiration pneumonia secondary to regurgitation) are other common signs.
Diagnosis, usually undertaken after an animal is weaned and begins regurgitating, is accomplished through chest X-rays (radiography) that demonstrate a dilation in the esophagus from the throat to the base of the heart. In most cases, barium (a gastrointestinal contrast material for use in radiography) is used to highlight this dilation.
Compared to other breeds, the Great Dane, German Shepherd, and Irish Setter are more commonly affected.
Definitive treatment of a persistent right aortic arch is always surgical. A constricting ring is placed around the abnormal vessel to allow it to degenerate. Follow-up care is designed to allow the esophagus to return to its normal size and function. That may involve feeding small amounts of moistened (or slurried) food throughout the day. Feeding from a height to allow gravity to take food into the stomach is also commonly recommended.
Depending on the time of intervention (earliest is best), esophageal problems may persist despite surgery, more so if the esophagus has been severely distended and has suffered severe nerve damage prior to intervention.
Affected dogs, their parents and siblings should not be bred. This is the only known means of prevention at the current time.
Mitral valve disease is not just a disease of the heart. It’s the disease of the heart for dogs, responsible for a full three-fourths of all canine heart diseases. It’s caused by a degenerative process thought to be genetic. A low-grade heart murmur may be the only early warning sign. Later on, coughing, exercise intolerance, rapid breathing, or fainting may develop. Treatment generally involves medication to ease the burden on the heart and promote better functioning, as well as medications to help control blood pressure and fluid retention. Other modalities include a low-sodium diet and exercise restriction.
This degenerative disease of the heart’s mitral valve (the left atrioventricular valve) is the most common cardiac condition in dogs. While it’s responsible for 75 percent of all heart diseases in dogs, it’s less common in cats.
This disease goes by the names endocardiosis, chronic valvular disease, and chronic valvular fibrosis.
Here’s some background:
The heart muscle is a pump that moves blood through the four chambers using involuntary contractions that promote the one-directional flow of the blood. The valves between the chambers form a tight seal that prevents the backflow of blood into the preceding chamber, thus keeping the blood flowing in the forward direction.
When the valves degenerate over time, they become thickened and deformed, thereby losing the tight seal and causing some blood to move backward in the heart. When the valve between the two left chambers of the heart (the mitral valve, between the left atrium and left ventricle) fails to form a tight seal, blood moves in a backward direction (into the left atrium) when the left ventricle contracts. This means the heart has to work harder to pump the volume of blood the body needs for normal functions.
Dogs with early or mild mitral valve disease may be identified by a heart murmur of low-grade severity heard loudest (using a stethoscope) over the left side of the chest. In these cases, no other clinical signs are typically observed. As this progressive disease advances, coughing, exercise intolerance, and increased respiratory rate and/or effort may develop. Fainting or collapsing may also occur, as well as sudden death (in rare cases).
Dogs with advanced or severe mitral valve disease may also experience symptoms consistent with heart failure. Heart failure occurs when the heart can no longer pump the requisite amount of blood for normal body functions. When this happens, fluid accumulates in the lungs, a condition veterinarians call pulmonary edema.
To identify this disease among dogs who suffer characteristic murmurs or other telltale symptoms, diagnosis is best achieved through chest X-rays, electrocardiograms (EKG), and echocardiography (ultrasound of the heart) with Doppler technology (demonstrating the flow of blood) to elucidate the abnormal change in the dimensions of the heart and the blood flow through the region of the mitral valve.
A consultation with a veterinary cardiologist may be recommended for some affected dogs.
Any dog can develop mitral valve disease. Cavalier King Charles Spaniels, Dachshunds, Poodles, and Chihuahuas are among the breeds that seem predisposed.
Treatment for mitral valve disease relies heavily on drugs. These include specific medications to ease the burden on the heart, diuretics for removal of excess fluid, medication to help regulate blood pressure, and other medications to help relieve the symptoms of heart failure. Additional therapies include a low-sodium diet and exercise restriction.
Luckily, a great many mitral valve disease patients don’t require any treatment at all until they show symptoms. And most who do tend to live well with drug therapy alone. Only the severely diseased tend to succumb, in spite of treatment.
Preventing mitral valve disease requires removing affected dogs from the breeding pool. This is especially critical for breeds like the Cavalier King Charles, whose extreme predisposition recommends that they receive cardiac ultrasounds (echocardiograms) before they enter any breeding program.