Abdominal aortic aneurysm

Synonyms

AAA
Aneurysm, abdominal aortic

Overview

Abdominal aortic aneurysms are aneurysms that occur in the part of the aorta that passes through the abdomen. They may occur at any age, but are most common in men between 50 and 80 years of age. A localized widening or bulging of the abdominal aorta which is a major blood carrying vessel. A rupture of the weakened bulge is considered very serious because of the large volume of blood carried by this vessel. Many people with an AAA have no symptoms, but some people have a pulsing sensation in the abdomen and/or pain in the back. If the aneurysm ruptures, it may cause deep, severe pain; nausea; vomiting; fast heart rate; clammy skin; and/or shock. About 20% of AAAs eventually rupture and are often fatal. The condition has multiple genetic and environmental risk factors, and may sometimes occur as part of an inherited syndrome. When more than one family member is affected, it may be considered "familial abdominal aortic aneurysm." Treatment depends on the size of the aneurysm and may include blood pressure medications, or surgery to repair the aneurysm.

Symptoms

  • Pulsatile epigastric mass
  • Abdominal pain
  • Gastric outlet obstruction
  • Shock
  • Poor peripheral pulses
  • Mild stomach ache
  • Back pain
  • Groin pain
  • Severe abdominal pain if aneurysm bursts
  • Severe back pain if aneurysm bursts
  • Clammy skin
  • Nausea and vomiting
  • Rapid heart rate

Causes

The exact cause of the condition is unknown. Factors that can increase your risk of developing the problem include:

  • Smoking
  • High blood pressure
  • Male gender
  • Genetic factors
  • Alcohol
  • Atherosclerosis
  • Family history
  • Other causes of the development of AAA include: infection, trauma, arteritis, cystic medial necrosis (m. Erdheim).

An abdominal aortic aneurysm is most often seen in males over age 60 who have one or more risk factors. The larger the aneurysm, the more likely it is to break open. This can be life-threatening.

Abdominal aortic aneurysm is thought to be a multifactorial condition, meaning that one or more genes likely interact with environmental factors to cause the condition. In some cases, it may occur as part of an inherited syndrome.

Having a family history of AAA increases the risk of developing the condition. A genetic predisposition has been suspected since the first report of three brothers who had a ruptured AAA, and additional families with multiple affected relatives have been reported. In some cases, it may be referred to as " familial abdominal aortic aneurysm."A Swedish survey reported that the relative risk of developing AAA for a first-degree relative of a person with AAA was approximately double that of a person with no family history of AAA. In another study, having a family history increased the risk of having an aneurysm 4.3-fold. The highest risk was among brothers older than age 60, in whom the prevalence was 18%.

While specific variations in DNA (polymorphisms) are known or suspected to increase the risk for AAA, no one gene is known to cause isolated AAA. It can occur with some inherited disorders that are caused by mutations in a single gene, such as Marfan syndrome and Ehlers-Danlos syndrome, vascular type. However, these more typically involve the thoracoabdominal aorta.

Because the inheritance of AAA is complex, it is not possible to predict whether a specific person will develop AAA. People interested in learning more about the genetics of AAA, and how their family history affects risks to specific family members, should speak with a genetics professional.

Prevention

  • Smoking cessation
  • Treatment of hypertension
  • Eat a heart-healthy diet, exercise  and reduce stress.

Diagnosis

Medical testing related to Abdominal aortic aneurysm:

  • Home Blood Pressure Tests
  • Home Blood Pressure Monitors
  • Home Heart Tests
  • Heart Rate Monitors
  • Irregular Heartbeat Detection
  • Heart Electrocardiogram (ECG)
  • Home Cholesterol Tests
  • Ultrasound of the abdomen when the abdominal aneurysm is first suspected
  • CT scan of the abdomen to confirm the size of the aneurysm
  • CTA (computed tomographic angiogram) to help with surgical planning

Prognosis

Survival rate statistics for Abdominal aortic aneurysm: The following are statistics from various sources about the survival rate for Abdominal aortic aneurysm:

  • 61% is the 5 year survival rate for patients who undergo surgical repair for abdominal aortic aneurysms in the US (American Family Physician, Vol 56, 1997).

Treatment

If you have bleeding inside your body from an aortic aneurysm, you will need abdominal aortic aneurysm repair.

If the aneurysm is small and there are no symptoms:

  • Surgery is rarely done.
  • You and your doctor must decide if the risk of having surgery is smaller than the risk of bleeding if you do not have surgery.
  • Your doctor may want to check the size of the aneurysm with ultrasound tests every 6 months.

Most of the time, surgery is done if the aneurysm is bigger than 2 inches (5.5 cm) across or growing quickly. The goal is to do surgery before complications develop.

There are two types of surgery:

  • Traditional (open) repair. A large cut is made in your abdomen. The abnormal vessel is replaced with a graft made of man-made material.
  • Endovascular stent grafting. This procedure can be done without making a large cut in your abdomen, so you may recover more quickly. This may be a safer approach if you have certain other medical problems. Endovascular repair can sometimes be done for a leaking or bleeding aneurysm.

Resources

  • NIH