Aneurysm, especially pseudoaneurysm

An aneurysm is a bulging, weakened area in the wall of a blood vessel resulting in an abnormal widening or ballooning greater than 50 percent of the normal diameter (width). An aneurysm may occur in any blood vessel, but is most often seen in an artery rather than a vein.

Types of aneurysms

An aneurysm may be located in many areas of the body, such as blood vessels of the brain, the aorta (the largest artery in the body), the intestines, the kidney, the spleen, and the vessels in the legs. The most common location of an aneurysm is the aorta, which carries oxygenated blood from the heart to the body. An aneurysm can be characterized by its location, shape and cause.

The shape of an aneurysm is described as being fusiform or saccular, which helps to identify a true aneurysm. The more common fusiform-shaped aneurysm bulges or balloons out on all sides of the blood vessel. A saccular-shaped aneurysm bulges or balloons out only on one side.

A pseudoaneurysm, or false aneurysm, is an enlargement of only the outer layer of the blood vessel wall. A false aneurysm may be the result of a prior surgery or trauma. Sometimes, a tear can occur on the inside layer of the vessel resulting in blood filling in between the layers of the blood vessel wall creating a pseudoaneurysm.

Because an aneurysm may continue to increase in size, along with progressive weakening of the artery wall, surgical intervention may be needed. Preventing rupture of an aneurysm is one of the goals of therapy. The larger an aneurysm becomes, the greater the risk of rupture (bursting). With rupture, life-threatening hemorrhage (uncontrolled bleeding), and possibly death, may result.

What causes an aneurysm to form?

An aneurysm may be caused by multiple factors that result in the breaking down of the well-organized structural components (proteins) of the aortic wall that provide support and stabilize the wall. The exact cause is not fully known. Atherosclerosis (hardening of the arteries) is thought to play an important role in aneurysmal disease. Risk factors associated with atherosclerosis include, but are not limited to, the following:

• older age
• being male
• family history
• genetic factors
• hyperlipidemia (elevated fats in the blood)
• hypertension (high blood pressure)
• smoking
• diabetes

Other specific causes of aneurysms are related to the location of the aneurysm. Examples of aneurysms in the body and their causes may include, but are not limited to, the following:

Type of Aneurysm	Causes of Aneurysms
Abdominal Aortic Aneurysm (AAA)	atherosclerosis (especially in the segment of the abdominal aorta below the kidneys, called an infrarenal aortic aneurysm) genetic disorders giant cell arteritis (a disease that causes inflammation of the temporal arteries and other arteries in the head and neck, causing the arteries to narrow, reducing blood flow in the affected areas; may cause persistent headaches and vision loss) infection
Cerebral Aneurysm	congenital (present at birth) high blood pressure atherosclerosis head trauma
Common Iliac Artery Aneurysm	atherosclerosis pregnancy infection trauma after lumbar or hip surgery
Femoral and Popliteal Artery Aneurysm	atherosclerosis trauma congenital disorders

What are the symptoms of an aneurysm?

Aneurysms may be asymptomatic (no symptoms) or symptomatic (with symptoms). Symptoms associated with aneurysms depend upon the location of the aneurysm in the body.

Symptoms that may occur with different types of aneurysms may include, but are not limited to, the following:

Type of Aneurysm	Symptoms Associated with Aneurysm Type
Abdominal Aortic Aneurysm (AAA)	constant pain in abdomen, chest, lower back or groin area
Cerebral Aneurysm	sudden severe headache, nausea, vomiting, visual disturbance, loss of consciousness
Common Iliac Aneurysm	lower abdominal, back and/or groin pain
Femoral and Popliteal Artery Aneurysm	easily palpated (felt) pulsation of the artery located in the groin area (femoral artery) or on the back of the knee (popliteal artery)

The symptoms of an aneurysm may resemble other medical conditions or problems. Always consult your physician for more information.

How are aneurysms diagnosed?

Selection of a type of diagnostic examination is related to the location of the aneurysm. In addition to a complete medical history and physical examination, diagnostic procedures for an aneurysm may include any, or a combination, of the following:

• computed tomography scan (also called a CT or CAT scan)
  A diagnostic imaging procedure that uses a combination of X-rays and computer technology to produce cross-sectional images (often called slices), both horizontally and vertically, of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat, and organs. CT scans are more detailed than standard X-rays.
• magnetic resonance imaging (MRI)
  A diagnostic procedure that uses a combination of large magnets, radiofrequencies and a computer to produce detailed images of organs and structures within the body.
• echocardiogram (also called echo)
  A procedure that evaluates the structure and function of the heart by using sound waves recorded on an electronic sensor that produce a moving picture of the heart and heart valves.
• arteriogram (angiogram)
  An X-ray image of the blood vessels used to evaluate various conditions, such as aneurysm, stenosis (narrowing of the blood vessel), or blockages. A dye (contrast) will be injected through a thin flexible tube placed in an artery. This dye will make the blood vessels visible on the X-ray.
• ultrasound
  Uses high frequency sound waves and a computer to create images of blood vessels, tissues and organs. An ultrasound is used to view internal organs as they function, and to assess blood flow through various vessels.

Treatment for aneurysms:

Specific treatment will be determined by your physician based on:

• your age, overall health and medical history
• extent of the disease
• your signs and symptoms
• your tolerance of specific medications, procedures or therapies
• expectations for the course of the disease
• your opinion or preference

Treatment options for an aneurysm may include one or more of the following:

• controlling or modifying risk factors - steps such as quitting smoking, controlling blood sugar if diabetic, losing weight if overweight or obese, and controlling dietary fat intake may help to control the progression of the aneurysm
• medication - to control factors such as hyperlipidemia (elevated levels of fats in the blood) and/or high blood pressure
• surgery - the type of surgery performed will depend on the location and type of the aneurysm