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Overview

An aneurysm is a weak part of the artery wall. Pressure from inside the artery causes the weak area to bulge beyond the normal width of the blood vessel. An abdominal aortic aneurysm is an aneurysm in the lower part of the aorta, the large artery that runs through the torso.

Abdominal aortic aneurysm: what you need to know

  • Abdominal aortic aneurysm is sometimes called (Abdominal aortic aneurysm) AAA , or Triple A.

  • Older, long-term smokers Smokers are at particularly high risk for abdominal aortic aneurysm.

  • Many people have no symptoms and do not know they have an aortic aneurysm until it ruptures, which is often quickly fatal.

  • When symptoms do occur, they include pain in the back or near the belly button. Extremely severe pain may indicate a rupture that requires emergency treatment.

  • Small, slow-growing aortic aneurysms can be treated with watchful waiting, lifestyle changes, and medications. Large or rapidly growing aortic aneurysms may require surgery.

What is an abdominal aortic aneurysm?

The aorta is the largest blood vessel in the body. It carries oxygenated blood from the heart to the rest of the body. An aortic aneurysm is a bulging, weak area in the wall of the aorta. Over time, blood vessels can swell and be at risk of rupture (rupture) or separation (dissection). This can cause life-threatening bleeding or even death.

Aneurysms most commonly occur in the part of the aorta that passes through the abdomen (abdominal aortic aneurysm).

Once formed, an aneurysm gradually grows in size and weakens. Treatment for an abdominal aneurysm may include surgery to repair or remove the aneurysm, or the insertion of a metal mesh coil (stent) to support the blood vessel and prevent rupture.

Abdominal aortic aneurysm shape

The more common shape is fusiform , which appears balloon-like on all sides of the aorta. A bulging artery is classified as a true aneurysm only if its width increases by 50%.

The sac-like shape is a bulge in only one location on the aorta. Sometimes called a pseudoaneurysm . This usually means the lining of the artery wall is torn, which can be caused by an injury or ulcer to the artery.

What causes abdominal aortic aneurysm?

Many factors can cause the aortic wall tissue to rupture and lead to an abdominal aortic aneurysm. The exact cause is not entirely clear. However, atherosclerosis is thought to play an important role. Atherosclerosis is the buildup of plaque, which is a deposit of fatty material, cholesterol, cellular waste, calcium and fibrin in the inner walls of arteries. Risk factors for atherosclerosis include:

  • Age (over 60 years old)

  • Males (the incidence rate in males is 4 to 5 times that in females)

  • Family history (first-degree relatives such as father or brother)

  • genetic factors

  • high cholesterol

  • hypertension

  • smokes

  • diabetes

  • obesity

Other conditions that may cause abdominal aneurysms include:

  • Connective tissue disorders such as Marfan syndrome, Ehlers-Danlos syndrome, Turner disease, and polycystic kidney disease

  • Congenital (present at birth) defects, such as bicuspid aortic valve or coarctation of the aorta

  • Inflammation of the temporal artery and other arteries in the head and neck

  • trauma

  • Infections such as syphilis, salmonella, or staph (rare)

What are the symptoms of abdominal aortic aneurysm?

About three-quarters of abdominal aortic aneurysms cause no symptoms. Aneurysms can be found with X-rays, computed tomography (CT or CAT) scans, or magnetic resonance imaging (MRI) done for other reasons. Because abdominal aneurysms may have no symptoms, they are called "silent killers." Because it can rupture before a diagnosis is made.

Pain is the most common symptom of abdominal aortic aneurysm. Pain associated with an abdominal aortic aneurysm may be located in the abdomen, chest, lower back, or groin area. The pain may be sharp or dull. Sudden, severe pain in your back or abdomen may mean an aneurysm is about to rupture. This is a life-threatening medical emergency.

An abdominal aortic aneurysm may also cause a pulsing sensation in the abdomen that resembles a heartbeat.

Symptoms of abdominal aortic aneurysm may look like other medical conditions or problems. Be sure to see a doctor for a diagnosis.

How is an aneurysm diagnosed?

Your doctor will conduct a complete medical history and physical examination. Other possible tests include:

  • Computed tomography scan (also called CT or CAT scan). This test uses X-ray and computer technology to make horizontal or axial images of the body (often called slices). CT scans can show detailed images of any part of the body, including bones, muscles, fat and organs. CT scans are more detailed than standard X-rays.

  • Magnetic resonance imaging (MRI). This test uses a combination of large magnets, radiofrequency, and computers to produce detailed images of organs and structures in the body.

  • Echocardiogram (also called echo). This test evaluates the structure and function of the heart using sound waves recorded by an electronic sensor that produces dynamic images of the heart and its valves, as well as structures within the chest, such as the lungs and the areas surrounding the lungs and chest organs.

  • Transesophageal echocardiography (TEE). This test uses ultrasound of the heart to check for aneurysms, heart valve conditions, or tears in the lining of the aorta. TEE is done by inserting a probe with a sensor on the end into the throat.

  • Chest X-ray. This test uses invisible beams of electromagnetic energy to capture images of internal tissues, bones, and organs onto film.

  • Arteriography (photography of blood vessels) . This is an X-ray image of a blood vessel and is used to evaluate conditions such as aneurysms, narrowing or blockage of blood vessels. A dye (contrast agent) will be injected through a thin, flexible tube placed in the artery. The dye makes the blood vessels visible on X-rays.

What is the treatment for abdominal aortic aneurysm?

Treatment may include:

  • Monitoring is done with MRI or CT. These tests are done to check the size and growth rate of the aneurysm.

  • Manage risk factors. Steps such as quitting smoking, controlling blood sugar (if you have diabetes), losing weight (if overweight), and eating a healthy diet may help control the progression of aneurysms.

  • drug. Used to control factors such as high cholesterol or high blood pressure.

  • Operation:

    • Open abdominal aortic aneurysm repair. A large incision is made in the abdomen to allow the surgeon to see and repair the abdominal aortic aneurysm. Mesh metal coil-like tubes called stents or grafts may be used. The graft is sutured to the aorta, connecting one end of the aorta at the site of the aneurysm to the other. Open repair is the standard surgical procedure for abdominal aortic aneurysms.

    • Endovascular aneurysm repair (EVAR). EVAR requires only a small incision in the groin. Using X-ray guidance and specially designed instruments, surgeons can repair the aneurysm by inserting a stent or graft into the aorta. Graft material can cover the stent. The stent helps keep the graft open and in place.

A small aneurysm or an aneurysm that does not cause symptoms may not require surgery until it reaches a certain size or grows rapidly in a short period of time. Your doctor may recommend "watchful waiting." This may include ultrasound, duplex, or CT scans every 6 months to closely monitor the aneurysm, and possibly blood pressure-lowering medications to control high blood pressure.

If the aneurysm is causing symptoms or is large, your doctor may recommend surgery.

Operation

Surgery may be needed if the aneurysm is large or grows rapidly, increasing the chance of rupture. Women with large aneurysms are more likely than men to have aneurysm rupture.

For suprarenal (above the kidney) AAA, only open surgery is available in the United States.
However, AAA located at or below the kidneys can be treated with open surgery or endovascular (endovascular means "within a blood vessel" and is considered minimally invasive.) surgery.

Not all patients can tolerate the risks of open surgery, so endovascular repair is a good option. Unfortunately, not all patients have anatomy suitable for endovascular repair. Please consult your vascular surgeon to find out which technique is best for you.

    • Open aneurysm repair : A large incision is made in the abdomen to repair the aneurysm. Make an incision in the aorta the same length as the aneurysm. Repairs are made using cylinders called grafts. The graft is made of polyester fabric or polytetrafluoroethylene (PTFE, a non-textile synthetic graft). The graft is sutured to the aorta from above to below the aneurysm site. The artery wall is then sutured to the graft.

    • Endovascular aneurysm repair (EVAR) : A small incision is made in the groin. Using X-ray guidance, the stent graft is inserted into the femoral artery and delivered to the aneurysm site. A stent is a thin metal mesh frame shaped into a long tube, while a graft is a mesh-covered fabric made of a polyester fabric called PTFE. The stent holds the graft open and in place. EVAR is only used in infrarenal (below the kidneys) AAA. Patients in high-risk groups may tolerate it more easily. However, grafts sometimes slip and may need to be repaired later.

  • Stent-graft : When the aneurysm is next to the kidney (kidney) or involves the renal artery, the previous standard treatment was open surgery. This is because traditional stent grafts do not have openings to accommodate the branches from the aorta to the kidneys. In 2012, the FDA approved the fenestrated stent graft, which is now used in several vascular surgery programs, including Johns Hopkins University. The fenestrated stent graft is made to the precise dimensions of each patient's aorta so that the openings of the renal arteries are in the correct location to maintain circulation to the kidneys.

What is aortic dissection?

Aortic dissection begins with a tear in the lining of the thoracic aorta wall. The aortic wall is composed of 3 layers of tissue. When a tear occurs in the innermost layer of the aortic wall, blood is directed to the aortic wall that separates the layers of tissue. This causes the aortic wall to weaken and potentially rupture. Aortic dissection can be a life-threatening emergency. The most common symptom of aortic dissection is sudden, severe, persistent chest or upper back pain, sometimes described as "tearing" pain. or "tear". The pain may move from one place to another.

When aortic dissection is diagnosed, surgery or stent placement is usually performed immediately.

What causes aortic dissection?

The cause of aortic dissection is unknown. However, several risk factors associated with aortic dissection include:

  • hypertension

  • Connective tissue disorders such as Marfan disease, Ehlers-Danlos syndrome, and Turner disease

  • Cystic medial disease (degenerative disease of the aortic wall)

  • Aortitis (inflammation of the aorta)

  • atherosclerosis

  • Bicuspid aortic valve (there are only 2 cusps or leaflets in the aortic valve instead of the normal 3 cusps)

  • trauma

  • Coarctation of the aorta (narrowing of the aorta)

  • Too much fluid or volume in the circulation (hypervolemia)

  • Polycystic kidney disease (a genetic disorder characterized by the growth of large, fluid-filled cysts in the kidneys)

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