Types of Aneurysms in Dogs

Aneurysms in dogs are extremely dangerous because they can result in immediate loss of life, although some dogs are lucky enough to survive. The survival of the dog, however, depends on what type of aneurysm occurs. There are three types of aneurysms in dogs: aortic, cerebral and peripheral. It is important that dog owners understand both the risk factors for aneurysms in dogs as well as the types of aneurysms which can affect dogs.

Aneurysm Risk Factors

In dogs, aneurysms can be caused by an underlying congenital condition that goes unnoticed until the event of the aneurysm. However, more commonly, aneurysms in dogs are the result of particular health conditions which contribute to the development of an aneurysm.

Risk factors for aneurysms in dogs include:

  • Atherosclerosis - A plaque formation in the arteries reducing blood flow throughout the body. In dogs, atherosclerotic conditions typically result from unhealthy diets and excessive table scrap feeding.
  • Obesity – Dogs do require a nutritious, well-balanced diet. Again, excessive table scrap feeding and unhealthy dieting can lead to canine obesity, which is a serious risk for many types of aneurysms.
  • High blood pressure – Dogs usually experience high blood pressure as the secondary condition of a primary health condition such as kidney failure; so it is important to keep all primary health conditions under control.

Dogs and Aortic Aneurysms

The aorta is the largest artery in the dog’s body. It stems from the left ventricle of the heart down into the abdomen. Aortic aneurysms in dogs can be classified as either thoracic aortic aneurysms (TAA) or abdominal aortic aneurysms (AAA).

Thoracic aortic aneurysms in dogs are aneurysms which occur at the chest level where the aorta extends into the chest. This type of aneurysm generally occurs when the walls of the aorta become weak as the result of some contributing risk factor. In the case of TAAs, the branch of the aorta closest to the heart actually enlarges and creates undue pressure on the thoracic aorta, generally as the result of improper closure of one of the heart valves.   

Abdominal aortic aneurysms in dogs are aneurysms which occur at the level of the abdominal aorta. Again, this is generally caused by an excessive amount of pressure from an improperly functioning valve in the heart.

Cerebral Aneurysms in Dogs

Dogs affected by cerebral aneurysms are often the least likely to survive. A cerebral aneurysm in dogs occurs when one of the arteries in the brain rupture. This type of aneurysm causes immediate hemorrhage inside the brain, which can lead to immediate coma or death.

Peripheral Aneurysms in Dogs

Peripheral aneurysms in dogs are those that occur at any other point throughout the body other than the aorta or within the brain. While peripheral aneurysms can affect any artery of the dog’s body, the most common are the popliteal artery (located behind the knee), the femoral artery (located within the groin) and the carotid artery (located in the neck).

It is important to note that peripheral aneurysms and aortic aneurysms are not typically as life-threatening for dogs as cerebral aneurysms. However, because any type of aneurysm can jeopardize a dog’s life or impair its quality of living, it is important to recognize the need for immediate veterinary evaluation during the onset of an aneurysm.