Pet Owner Articles & Papers
What is an arrhythmia? An arrhythmia is a disturbance in the electrical activity of the heart. Dogs and cats may have arrhythmias secondary to underlying cardiac disease or from non-cardiac causes. Careful assessment of the heart by the veterinarian is necessary to determine any potential causes and blood tests, radiographs (x-rays), electrocardiography (EKG/ECG), Holter monitoring (24 hour ambulatory EKG), event monitoring, and echocardiography (ultrasound of the heart) may be required to identify any causes. If an arrhythmia causes an animal to have serious problems by reducing blood flow or blood pressure, resulting in an exacerbation of heart failure or causing […]
Dogs that have congenital pulmonic stenosis (PS) have a narrowed outflow of the right side of the heart. When this results from fusion of the pulmonic valve leaflets, these patients may benefit from a palliative catheter-based procedure called balloon valvuloplasty. Dogs are diagnosed with PS using the history, physical examination and complete echocardiography (cardiac ultrasound). In some cases, thoracic radiographs and EKG are useful, but not diagnostic. The ideal candidate for balloon valvuloplasty has severe PS as determined by echocardiography with mild secondary right heart muscle thickening and fusion of the commisures of the pulmonic valve leaflets. Patients that have mild-moderate PS may not […]
Many different types of drugs may be used in dogs and cats suffering from bronchitis and/or pneumonia. Generally four types of drugs are most commonly used, and include antibiotics (antimicrobials), corticosteroids, bronchodilators and antitussives. Depending on the problems, different drugs in different combinations may be prescribed. ANTIBIOTICS: Antibiotics (antimicrobials) are drugs that are used in patients suffering from bacterial infections. In patients with lung disease, they are typically used for those with bacterial pneumonia (infection of the lungs) or septic tracheitis/tracheobronchitis (infection of the airways). Some antibiotics are classified as bacteriostatic, which means they inhibit the growth of microorganisms, allowing […]
Chronic mitral valvular disease (CMVDz) is by far the most common acquired heart disease seen in dogs. This condition is also known by a number of different names, which occasionally leads to confusion for the average loved one owner. Chronic valvular disease may also be known as myxomatous valvular degeneration (MVD or MMVD for myxomatous mitral valvular degeneration), degenerative mitral valvular disease (DMVD) or mitral “endocardiosis.” Basically, age-related degeneration develops on one of the valves on the left side of the heart, which is known as the mitral valve. This disease may also affect other valves within the heart, and the tricuspid valve […]
Many small-breed dogs suffer from collapsing trachea. This is a condition in which the supporting cartilage rings for the windpipe are unable to maintain their shape, resulting in narrowing of the airway. This typically leads to chronic coughing, which is often characterized as having a honking sound (goose-honking). Severely affected patients may have marked difficulty breathing and even life-threatening airway obstruction. The most commonly affected breeds include the Yorkshire terrier and Pomeranian, though any small-breed dog may be affected. Large-breed dogs rarely have this problem. Diagnosis of tracheal collapse is made using the history, physical examination, and chest x-rays (thoracic […]
Cardiac drugs are used in patients at high risk for or suffering from congestive heart failure. Different types of drugs may be used in any given patient for a variety of reasons. The main classes of drugs include diuretics, antihypertensives, positive inotropics/inodilators, antithrombotics and antiarrhythmics. Supplements are occasionally advocated for use in patients with heart disease as well. The following information covers only the most commonly used drugs in each class, and by no means is a comprehensive review. It is very important that all cardiac drugs intended for use in dogs in cats are placed out of the reach […]
What is a cardiac clearance? A cardiac clearance is a physical examination performed by a licensed veterinarian (DVM – Doctor of Veterinary Medicine, VMD – Veterinary Medical Doctor) who determines that the physical examination is within normal limits. Many different types of clearances exist, including orthopedic (i.e. to rule-out hip dysplasia), ophthalmologic (i.e. to rule-out potentially hereditary eye problems such as progressive retinal atrophy), and cardiac – which is to rule-out evidence of congenital/hereditary cardiovascular disease (i.e. conditions such as subaortic stenosis/SAS, or other conditions, such as patent ductus arteriosis/PDA). Typically, a cardiac clearance should be performed for all potential breeding animals from 1-2 years of […]
Dogs and cats may suffer from a variety of ailments that lead to chronic coughing. Coughing is the forcible exhalation of air against a closed glottis. This may be soft/wet sounding, hacking/dry/harsh sounding or have a honking component. Coughing that has been present on a daily basis for over a few weeks in duration is generally considered to be chronic. Dogs frequently will have a gagging activity following a spell of coughing, which may be confused with “having something stuck in the throat,” and is the result of an attempt to clear mucus from the airways. Coughing cats are frequently […]
Chylothorax is the abnormal accumulation of lymphatic fluid rich in fats (triglycerides) within the chest cavity. This fluid may build up to the extent that patients have difficulty expanding their lungs, resulting in difficult or labored breathing. Chylothorax may develop as primary problem and have no obvious underlying cause. This is referred to as idiopathic chylothorax. This occurs most commonly in the cat. Occasionally, patients may develop chylothorax secondary to other problems, most commonly congestive heart failure or neoplasia (cancer). Chylous pleural effusion is diagnosed on the basis of a combination of the history, physical examination, chest x-rays, and fluid analysis […]
Arrhythmias are abnormal heart rhythms. Some arrhythmias are normal variants (i.e. respiratory sinus arrhythmia) and completely benign. Some may be abnormal, but not dangerous (i.e. premature beats). Some arrhythmias are associated with alarming clinical signs such as fainting (passing out, syncope) and can be life-threatening in certain circumstances. The following covers only the most common arrhythmias and is by no means comprehensive. Atrial fibrillation Atrial fibrillation (AF or “A-fib”) is not uncommon in the dog and rare in cats. Typically, atrial fibrillation is associated with underlying structural heart disease with severe secondary heart chamber enlargement (usually left atrial enlargement). The top […]
Canine Chronic Mitral Valvular Disease: Chronic Mitral Valve Disease (CMVDz, CMD, also known as myxomatous valvular degeneration/MVD or “endocardiosis”) is a degenerative condition of the heart valves and supporting structures that causes leakage of blood backwards through the heart due to the inability of the valves to form a tight seal. This disease is diagnosed most effectively by echocardiography (ultrasound of the heart). The mitral valve is commonly the most severely affected valve. Over time, this can cause heart chamber enlargement. The body’s response is to retain salt and water. The increase in blood volume that results helps the patient […]
Dogs and cats may occasionally be affected by heart disease that is the result of a congenital heart defect. This means there was an abnormality of the heart that arose during early development within the womb. Diagnosis of congenital heart disease is made on the basis of the history, physical examination, as well as the results of diagnostic tests. These tests may include chest x-rays (thoracic radiographs), electrocardiography (EKG), and echocardiography (ultrasound of the heart). Rarely, cardiac catheterization or necropsy (animal autopsy) is required for a diagnosis. The most commonly encountered congenital heart defects in dogs include patent ductus arteriosus, subaortic stenosis, […]
What is the treatment for congestive heart failure? The mainstay of medical therapy of congestive heart failure is the careful use of a class of drugs called diuretics. Diuretics cause the kidneys to excrete sodium (salt), which in turn causes water loss through the kidneys, resulting in a reduction of the overall body water and blood volume. This lowers pressure on the veins in the lung tissue and thereby decreases the formation of heart failure fluid (pulmonary edema). Since diuretics affect the kidneys, overzealous use can lead to dehydration and blood salt (electrolyte) imbalances. This may be manifested as lethargy, vomiting […]
An often neglected component of the management of any patient with an illness is diet modification. Generally speaking, patients at high risk for or those with a history of congestive heart failure should be on at least a moderately sodium (salt) restricted diet. This means that the diet should contain no more than 100 mg of sodium per 100 gram dry weight. Most senior or geriatric-formulated dog foods meet this criterion. There are prescription diets available that are moderate to severely sodium-restricted (i.e. less than 50 mg sodium per 100 gram dry weight). By limiting the dietary intake of sodium, we can help control the fluid […]
Dilated cardiomyopathy (DCM, dilatative cardiomyopathy, idiopathic cardiomyopathy, congestive cardiomyopathy) is a disease of the heart muscle, most commonly affecting large to giant-breed dogs, and is seen much less frequently in cats. Patients with dilated cardiomyopathy typically have one or more genetic defects that result in abnormal heart muscle proteins. Over time, this results in enlargement of the heart muscle and a weakened contraction. Different breed may develop DCM and the prognosis tends to vary somewhat as a result. Doberman Pinschers commonly develop DCM. Unfortunately, this breed tends to have the worst version of this condition. Dobermans with DCM are at […]
Endocarditis is infection of the heart valves. Fortunately, this tends to be an uncommon problem in the dog and is rare in cats. Working dogs (i.e. police dogs, German Shepherds, Belgian Malinois, etc.), Doberman Pinschers, Boxers, Golden Retreivers and Rottweilers may be predisposed. The most commonly affected heart valve in dogs and cats is the aortic valve. The second most common valve seen is the mitral valve. Both of these are on the left side of the heart, and if severe enough of a leak develops, this may lead to heart chamber enlargement and eventually left-sided congestive heart failure (CHF, LCHF). Other […]
What is a genetic predisposition? A genetic predisposition means that an individual may have a tendency to develop certain diseases as a consequence of inherited defects in the genes. A gene is a segment of a chromosome, which is the portion of a cell that contains the instructions to produce certain substances, commonly proteins. These proteins have a job to do, and abnormal proteins may be unable to perform their job correctly. This can ultimately lead to acquired cardiac (heart) disease. What is a breed predisposition? Since breeds are created by allowing closely-related individuals to procreate, a genetic predisposition for heart disease […]
Cats may occasionally be affected with a disease referred to as asthma/bronchitis. Asthma causes the airways (bronchi) in the lungs to sporadically constrict. This condition is termed bronchoconstriction, and severely restricts airflow to the lung tissue, causing patients to gasp for air. This is typically manifested by open-mouthed breathing in the cat. Bronchitis causes the airways to become inflamed. This results in some narrowing of the airways, as well as excessive mucus production, which in turn can lead to chronic coughing in addition to difficulty breathing. Most cats have a combination of asthma and bronchitis, so we refer to this as feline asthma/bronchitis complex […]
Hypertrophic cardiomyopathy (HCM) is a disease of the heart muscle and most commonly affects cats. It rarely occurs in dogs. HCM is the result of one or more specific genetic defects that results in abnormal heart muscle proteins. This eventually leads to heart muscle thickening, usually affect the left ventricle of the heart. Thickening of the heart muscle makes it more difficult for the heart to relax properly. This leads to elevated pressures within the heart, and can result in secondary heart chamber enlargement, congestive heart failure and even clot formation. Patients with mild heart muscle thickening and no chamber […]
Congestive heart failure is a clinical diagnosis – one that is made by the veterinarian taking into account a loved one’s history and physical examination findings in addition to the results of testing, which may include chest x-rays, echocardiography (ultrasound of the heart), electrocardiography (EKG, ECG), blood pressure, blood work , etc. Heart failure happens because patients have heart disease, however just because a loved one has heart disease, doesn’t automatically mean that it has heart failure. Many loved ones have mild heart disease and can live for years only to succumb to some other issue. Some loved ones with more serious heart disease however can […]
Patients that have symptomatic bradycardia (slow heart rates) may benefit from the placement of a permanent artificial pacemaker. This is most commonly performed in dogs suffering from electrical heart disease with arrhythmias such as atrioventricular (AV) block or sick sinus syndrome. Occasionally, dogs are paced for atrial standstill. Cats rarely require artificial pacing, but if they do, it’s usually because they have AV block. These arrhythmias cause the heart to beat very slowly. Patients may have symptoms including lethargy, weakness and even collapse or fainting (syncope). Patients with long-term bradycardia may even develop secondary congestive heart failure. Candidates for artificial pacing ideally have […]
Cardiomyopathy in cats comprises an incompletely understood group of diseases. The term cardiomyopathy means heart muscle disease, and encompasses multiple different types. The most common and extensively studied kind that is diagnosed in cats is hypertrophic cardiomyopathy (HCM), and is not the focus of this discussion. The other cardiomyopathies include dilated cardiomyopathy, restrictive cardiomyopathy, and unclassified or ischemic cardiomyopathy. It is unclear what role myocarditis/endomyocarditis (inflammation of the heart muscle) plays in the development and/or exacerbation of cardiomyopathy in cats. Dilated Cardiomyopathy: Dilated cardiomyopathy (DCM) in cats is characterized by dilation of the heart chambers with a decrease in the muscle pump […]
Pulmonary hypertension (PHT, pulmonary arterial hypertension or PAH) is a condition in which the blood pressure in the lungs is excessively elevated. The normal blood pressure in the pulmonary artery is no more than 30 mmHg. Patients with severe pulmonary hypertension may have pulmonary arterial pressures greater than 80 mmHg. This condition may rarely develop suddenly secondary to a large clot called a pulmonary thromboembolism. Patients with massive pulmonary thromboemboli typically have severe difficulty breathing and unfortunately tend to pass away suddenly. Most commonly, pulmonary hypertension develops over a long period of time. Primary pulmonary hypertension occurs in the absence of obvious underlying lung […]
Dogs may occasionally develop pulmonary (lung) disease. There are many different types of diseases that may affect a dog’s lungs, including heartworm disease, congestive heart failure and airway collapse (collapsing trachea and mainstem bronchus collapse). The following is a brief description of other causes of lung disease in the dog. Pneumonia is infection in the lungs. Pus accumulates within the lung tissue, and this leads to coughing and difficult or labored breathing in severe cases. Pneumonia is usually caused by bacterial infection, and may be initiated by aspiration – which is the inhalation of vomitus or water. The aspiration of vomitus is termed aspiration […]
Unfortunately, some dogs and cats may experience sudden cardiac death (SCD). This often unexpected event can lead to a lot of unanswered questions and frustration for many grieving loved one owners. When a loved one is otherwise not apparently ill or obviously exposed to a toxin of some kind, the heart is usually blamed as the underlying cause. Cardiac arrhythmias are probably the most common underlying cause of true sudden cardiac death. An arrhythmia is an abnormal heart rhythm. Ventricular arrhythmias including ventricular tachycardia may predispose a loved one to sudden cardiac death. Usually what happens is the heart rate becomes very fast […]
Dogs and cats may occasionally experience syncope (fainting). Syncope may occur for a number of different reasons. Basically, the blood pressure falls low enough that the brain doesn’t receive enough oxygen, resulting in transient loss of consciousness. When dogs and cats lose consciousness, it may appear to be a seizure. Most of the time, patients will stop whatever it is they were doing, stretch out their front legs, stretch their neck and throw their head back, fall over to one side or another, and may involuntarily vocalize, urinate and/or defecate. Usually, fainting episodes are brief, lasting less than 10-20 seconds […]
Patients that have severe tracheal collapse with symptoms of or documented airway obstruction that are refractory to medical management may be candidates for tracheal stent implantation. A tracheal stent is a self-expanding metallic device which is placed within the trachea (windpipe) and is used to hold the airway open. Many different considerations must be made when evaluating patients for stent implantation. Tracheal stent implantation is a last resort for patients with severe, refractory tracheal collapse. Stents are an imperfect treatment for a terrible problem and do not “fix” tracheal collapse. Candidates for tracheal stent implantation have certain qualities that we […]
Dogs and cats may occasionally suffer from systemic hypertension, which is a higher than normal arterial blood pressure. Blood pressure is evaluated in small animals in nearly the same way that it is in humans. Basically, a cuff is inflated on a limb (or occasionally the tail), and a Doppler probe is used to hear the pulse in an artery. The cuff is situated between the artery and the heart itself. The cuff is inflated until the pulse disappears, and the pressure in the cuff is slowly decreased until the pulse returns. The pressure at which this happens is the […]
