Accurate diagnosis of heart disease depends on using the right products at the right time

Recognizing signs of heart disease in companion animals and intervening early could enhance, if not save, a pet’s life. But to do so, veterinarians require the right products and equipment. By understanding the issues associated with heart disease and diagnosis, distributor reps can ensure their customers are well prepared to care for their patients.

How it affects pets
The good news for dogs and cats is that, compared to humans, they are equipped with a better network of arteries that feed the heart muscle. Whereas people have two central arteries, which are prone to becoming clogged by fatty foods, dogs and cats in particular are not susceptible to coronary artery disease. Still, they have their own set of concerns when it comes to staying heart healthy.
As many as 15 percent of young dogs have heart disease and the risk increases with age, according to IDEXX Laboratories (Westbrook, Maine). Up to 60 percent of older dogs are afflicted.
Chronic mitral valve disease and dilated cardiomyopathy (DCM) are two types of heart disease that typically affect dogs. The more common of the two is chronic mitral valve disease. The mitral valve is located on the left side of the heart, between the left atrium and the left ventricle. When the left ventricle contracts, the mitral valve must be in the closed position to force blood through the arteries to the rest of the body. Over the years, the mitral valve can wear out and become leaky in older dogs, and the blood is channeled back into the atrium. As such, cardiac output is reduced and less blood is circulated throughout the body.
Mitral valve disease is progressive. In its early stages, dogs may resist exercise, quickly run out of breath and develop a heart murmur. Later, they may develop a soft cough while lying down at night. In the final stages of the disease, the lungs become congested, causing dogs to have trouble breathing.
Another common heart disease in dogs is dilated cardiomyopathy (DCM), a disease of the heart muscle that results in the thinning of the heart walls, weakened contractions and less effective pumping ability. Although dilated cardiomyopathy commonly affects larger breeds of dogs, it also affects some smaller breeds, such as cocker spaniels. Its symptoms are similar to those of mitral valve disease.
Cats, too, are susceptible to heart disease, the most common of which is hypertrophic cardiomyopathy. The walls of the heart thicken, making the heart an ineffective pump. Because cats do not present a heart murmur and they sleep a lot whether healthy or sick, there often are no early warning signs. But it is estimated that heart disease is present in as many as 15 percent of felines, according to IDEXX. By the time the disease is discovered, it usually is in its end stage.

How to detect
A basic cardiac exam begins with a routine physical. A good stethoscope enables the veterinarian to detect heart murmurs as the blood moves in the wrong direction across the heart. In the case of a leaky valve, the veterinarian can get an idea of which valve is leaky and to what degree.

Although the stethoscope is a necessary tool for detecting heart disease, there are a number of devices available for diagnosing it, including the following:
• X-ray and/or radiography. X-ray and radiography provide a silhouette of the heart, enabling the veterinarian to see its size and whether the lungs are congested. However, the interpretation of
an X-ray or radiograph is subjective, and if the animal is not positioned just so, the veterinarian may miss important signs. Also, in cats, the heart muscle expands equally on all sides, making it difficult to diagnose based on a silhouette image.
• BNP biomarker. At least one company offers a blood test designed to help diagnose or rule out heart disease in dogs and cats. It reportedly also helps differentiate heart disease from heart failure, and respiratory disease from heart disease. Because the test can be run in the veterinarian’s office, the veterinarian and client are provided with important information during the initial exam. Particularly for cats, who display no early warning signs of heart disease, a BNP test provides a dependable screen.
• Electrocardiogram (ECG). Depending on the results of the X-ray or radiograph, the veterinarian will refer the patient to a cardiologist for an ECG, which can determine the existence of a cardiac arrhythmia or abnormal heartbeat. Many veterianians perform ECGs in-office as well.
• Doppler. Another tool used by cardiologists, Doppler can help them track the blood flow.

How to sell
Veterinarians need help understanding the severity of their patients’ heart murmurs. As such, there is a need for additional diagnostic tools. However, their lack of awareness often prevents them from adding new devices to their practice. Distributor reps should ask several questions, such as the following, to get their customers thinking about the value of diagnostic tools:
• “How do you currently examine and diagnose your cardiac patients?”
• “How do you evaluate heart murmurs?”
• “How do you determine which of your patients should visit a cardiologist?”

It is especially important for sales reps to focus on when each test or tool should be used and why it
is applicable.
Armed with a good understanding of available diagnostic tools, reps can help their veterinarian customers do their best to protect their patients.

Editor’s note: Vet-Advantage would like to acknowledge the contribution of IDEXX Laboratories (Westbrook, Maine).

Sidebar:

Treating Heart Disease

The right treatment can enhance a pet’s quality of life

Heart disease in dogs and cats may not be preventable, but it is manageable, and veterinarians can treat the symptoms as they emerge. However, this often can be challenging, according to some experts. Distributor reps can help their veterinarian customers by making them aware of their options (drugs, therapies and diagnostics), as well as directing them to literature, Webinars and informative Web sites.

Several treatments are available today to keep heart patients more comfortable and, in some cases, help prolong their life:
• Diuretics. In patients with heart disease it is common for the heart to fill with fluid. Diuretics can facilitate fluid loss.
• Drugs/ACE inhibitors. Certain drugs help relieve muscles within blood vessels, enabling the heart to work more efficiently. Three common ones are pinobendan, which is used for dogs only, ACE inhibitors and enalapril (a type
of ACE inhibitor).
• Bronchodilators. Dogs with mitral valve disease commonly develop concurrent bronchial disease, which can be managed with the use of bronchodilators.
• Anticoagulants. Cats with heart disease often develop sticky platelets, which cause blood clots. Anticoagulants, such as heparin and warfarin, help thin the blood.
• Surgery. While surgery is an option, placing a dog on a bypass machine can be very complicated and it is rarely done.

Advancements in drug therapies and ACE inhibitors enable veterinarians to improve the quality and length of life for their canine and feline patients. Distributor reps can best service their customers by keeping them abreast of the latest technology.