Veterinary Cardiology

Echocardiography is a procedure utilizing ultrasound that allows the cardiologist to examine the inner structure of the heart.  WVRC is also equipped with Color Flow Doppler, a technology that can greatly enhance the ability to diagnose specific types of heart disease through ultrasound.

An electrocardiogram (EKG or ECG) is a testing procedure that looks at the electrical impulses created by the activity of the heart. Changes in electrical impulses occur when the heart lacks oxygen or has some other type of heart disease.

Puppies may be diagnosed with Patent Ductus Arteriosus (PDA), one of the most common congenital heart diseases found in pets.  It is an extra vessel that leads to abnormal blood flow and can ultimately shorten an animal’s lifespan.

The most common cardiomyopathy (heart muscle disease) in cats is hypertrophic cardiomyopathy. This form has many variations, and is defined by thickening of the primary heart muscle, the left ventricle.  A common secondary change in cats with cardiomyopathy is enlargement of the left atrium. This finding is particularly worrisome in cats because they are susceptible to blood clot formation.

Unfortunately, the development of a blood clot is unpredictable and can occur on any medication. Blood clot formation can result in a cat being paralyzed in the rear legs, limping on a front leg, exhibiting episodes of abnormal behavior or even sudden death.

Dilated Cardiomyopathy (DCM) is a disease of the heart muscle which causes the heart to enlarge and not function properly.  The disease usually afflicts larger breeds of dogs.  The occurence of Dilated Cardiomyopathy increases with age and typically has an age of onset between 4 to 10 years.  The cause of DCM in dogs is still unknown; however, many factors suggest a genetic cause.

The most common form of heart disease in dogs is valvular disease. This disease typically affects older, smaller breeds of dogs. The primary valve affected is the mitral valve, which is located on the middle of the left side of the heart. The edges of the valve become frayed and allow backward flow of blood within the heart. A normal heart valve keeps blood flowing in the forward direction only with no backward flow. With time, backward flow of blood overworks the heart and causes enlargement of both the primary muscle pump (the left ventricle) and the chamber that receives this backward flow (the left atrium). As the left ventricle enlarges, the strength of the pumping action deteriorates and medication to help this problem is required. With enlargement of the left atrium, the dog becomes at risk for the accumulation of fluid in the lungs (congestive heart failure.)

Systemic hypertension is a sustained elevation in arterial blood pressure. Typically, systolic blood pressure greater than 160-180 mmHg is considered abnormal (this may be an underestimation for the extremely stressed feline patient).  Hypertension that develops in the absence of underlying disease is known as primary hypertension.  Primary hypertension is very common in humans but this is not the case for small animals. In cats, systemic hypertension is most commonly secondary to renal disease and/or hyperthyroidism.  In dogs, systemic hypertension is most commonly secondary to renal disease, Cushing's disease (hyperadrenocorticism), diabetes mellitus, and/or pheochromocytoma (a tumor of the adrenal gland).