Canine stroke occurs when blood flow to the brain is disrupted because of a blocked or ruptured blood vessel. Because stroke results from illness or injury, it's not a hereditary condition in and of itself, but risk factors for stroke can be passed along to a dog by its parents. These risk factors include congenital diseases and predisposition to certain medical conditions that can result in stroke.
Types and Causes
Dogs can suffer two kinds of stroke. Hemorrhagic stroke, according to Dog-Health-Guide.org, happens when bleeding in the brain from a burst blood vessel disrupts blood flow to the brain. An ischemic stroke, which also stops blood flowing to the brain, is the result of a blocked artery. Stroke can be a side effect of head trauma or the consequence of a medical condition, including diabetes and kidney disease as well as high blood pressure and some forms of heart disease.
Determining Hereditary Cause
Inherited conditions are not always the cause of canine stroke, even in breeds predisposed to congenital heart disease or heart defects. If the vet is able to rule out causes such as toxins, illness or injury from head trauma or overheating, she may then look at the dog’s medical and family history to determine if the stroke resulted from a hereditary condition. This process involves looking at many factors, including the age the condition became evident, the breed and information about the dog’s litter mates or parents, if available.
Hereditary Risk Factors
Just like people, dogs can be predisposed to stroke because of underlying health conditions such as high blood pressure or kidney disease. Other canine conditions that can lead to stroke include hypothyroidism, or low thyroid hormone levels, which is hereditary in a variety of breeds including Afghan hounds and boxers. Cushing's disease, a hereditary disease of the adrenal glands, can cause hypertension, congestive heart failure and blood clots, with poodles, boxers, dachshunds and Boston terriers most commonly affected.
Symptoms and Diagnosis
Canine stroke can only be diagnosed and treated by a vet after a complete medical exam and testing, which usually includes blood work and imaging, such as an MRI or CT scan. Signs that your dog may be suffering a stroke, according to Dog-Health-Guide, can include loss of balance, walking in a circle, loss of bowel and bladder control, not turning the right way when you call his name, acting tired, sudden changes in behavior or blindness.