What is abdominal aortic aneurysm (AAA)?
The aorta is the largest artery in your body,and it carries blood away from your heart. Your aorta runs through your chest and into the abdomen. The abdominal aorta supplies blood to the lower part of the body. Just below the abdomen, the aorta splits into two branches that carry blood into each leg.
When a weak area of the abdominal aorta expands or bulges, it is called an abdominal aortic aneurysm (AAA). The pressure from blood flowing through your abdominal aorta can cause a weakened part of the aorta to bulge, much like a balloon. A normal aorta is about 1 inch (or about 2 centimeters) in diameter. However, an AAA can stretch the aorta beyond its safety margin.
Aneurysms are a health risk because they can burst, or rupture. A ruptured aneurysm can cause severe internal bleeding, which can lead to shock or even death. Fortunately, when diagnosed early, AAA can be treated, or even cured, with highly effective and safe treatments.
What are the symptoms?
Although you may not feel any symptoms with AAA, if you develop symptoms, you may experience one or more of the following:
- A pulsing feeling in your abdomen, similar to a heartbeat
- Severe, sudden pain in your abdomen or lower back. If this is the case, your aneurysm may be about to burst
- If your aneurysm bursts, you may suddenly feel intense weakness, dizziness, or pain, and you may eventually lose consciousness. This is a life-threatening situation and you should go to the hospital immediately.
On rare occasions, your feet may develop pain, discoloration, or sores because of material shed from the aneurysm
What causes an abdominal aortic aneurysm?
Physicians and researchers are not quite sure what causes AAA. The leading thought is that the aneurysm may be caused by inflammation in the aorta, which may cause its wall to break down.
Factors that can increase your risk of AAA include:
- being a man older than 60 years
- having an immediate relative, such as a mother or brother, who has had AAA
- having high blood pressure
- your risk of developing AAA increases as you age. AAA is more common in men than in women.
What tests will I need?
If the decision has been made that you should be assessed for suitability for an operation you will be admitted to hospital. You will admitted by a doctor who will take your history and examine you - during your admission, this process may be repeated many times, this is for your safety. Routine blood tests will be taken. Your regular medication may need to be changed. We usually administer daily heparin injections to prevent leg clots (DVT).
You will usually have an ultrasound scan and often a CT scan (specialised XRay) .
Your heart will be assessed using an ECG and you may require specialised tests such as an echocardiograph (a special ultrasound scan), a stress test (walking on a treadmill) or a coronary angiogram.
Your breathing will be assessed using a chest XRay, spirometry and/or special blood tests.
Your kidney function will be assessed using special blood tests.
When your tests have been completed. one of the surgical team will discuss your options with you and explain the surgical procedure. You will have an opportunity to ask any questions at this time and it is useful if you can arrange to have a family member present or for them to meet the surgical team at another time. You will be seen and assessed by an anesthetist who will explain your anaesthetic to you
Endovascular Aortic Aneurysm Repair (EVAR)
This is a relatively new technique that uses an endovascular stent graft (a tube composed of fabric supported by a metal meshwork or stent). It has been performed in our hospital in Tallaght since the hospital opened in 1998. Endovascular means "inside blood vessels" and these stent grafts can be positioned through one or two small incisions in the groin. Endovascular treatments allow you to leave the hospital sooner and recover more quickly, with less pain and a lower risk of complications and death than traditional surgery, because the incisions are smaller. However, as the techniques are relatively new, the longer term durability is unknown. It appears that those having endovascular repair of an aneurysm are more likely to need further surgery over the next few years than those having open surgery.
Am I suitable for EVAR?
About half of those who present with an AAA are suitable but if you are young (under 70) and otherwise fit, it may be more appropriate for you to have an open repair. Your surgeon will discuss this with you when all your tests are complete.
You must fast (nothing to eat or drink) from midnight on the night before your operation.
On the morning of surgery, we will confirm that a bed is available in the intensive care unit and you will be brought to the operating theatre.
The procedure is usually performed under epidural anaesthetic but may sometimes be performed using local anaesthesia injections only. Your anaesthetist may recommend a general anaesthetic in certain cases.
When you have been anaesthetised, your surgeon will make an incision in each groin. The endograft is introduced through these incisions (in two or more parts) and passed up inside your blood vessels into the aneurysm. It is assembled here under XRay guidance. View an animation of the procedure.
After the operation you will go to the intensive care unit for one to two days. There will be tubes in your arm veins and arteries and a tube in your nose and bladder but these will be removed over the next few days as you recover.
You will sit out on a chair on the first day after your operation and slowly build up your mobility over the next few days. A physiotherapist will help you keep your chest clear and ensure that you are coughing effectively.
Most people are ready for discharge in 5 days or so but you might prefer to go to a nursing home for a further two weeks convalescence. We can help you arrange this - the sooner enquiries are made the better.
Poor appetite, lack of energy and disturbed sleep are common and will resolve over weeks or months. You may begin walking straight away but heavier activity should be introduced gradually after 4 to 6 weeks. You will be back to normal by three months.
While every effort is made to avoid problems, serious complications occur in up to 15% of people having aneurysm surgery. These include:
- breathing problems (pneumonia)
- heart problems (heart attack or irregular heartbeat)
- kidney problems (kidney failure requiring dialysis).
If these problems occur, they may be life-threatening and the risk of death following aneurysm repair is between 5 and 10%. Serious bleeding during or after surgery, wounds problems or deep venous clots are uncommon but do occur.
A fever for a few days is common after surgery and does not necessarily indicate a major problem.
You will be seen regularly in the OPD and will need regular scans every 6-12 months or so for the rest of your life.