Aortic aneurysms are dilatations (or swellings) of the aorta, which is the main artery from the heart supplying blood to the body. They cost commonly occurain the abdoomen although they can occurin the chest. . They do not cause symptoms usually until they rupture, which is often fatal. They are investigated by performing an abdominal ultrasound or CT scan. If there is an aortic aneurysm, then there is a possibility that other arteries can also have an aneurysm, most commonly involving the leg artery behind the knee.
The risk of rupture is directly related to the maximum diameter, and treatment is advised when the aneurysm reaches 5.5cm, as this is the size where the risk of rupture overtakes the risk of treatment. The natural history of aortic aneurysms is to slowly enlarge (about 3-5mm per year) although they can remain static for years. Once an aneurysm is diagnosed, then 6-monthly or annual scans should be performed to monitor expansion rate.
The aneurysm should be treated before it ruptures, as the mortality after rupture is 75%, and even if the patient reaches hospital alive, there is still a 50% mortality. If repaired before rupture, the mortality is less than 5%.
The time-honoured treatment is an abdominal operation which sutures a bypass graft of Dacron material inside the aneurysm. This is a major procedure and requires about 7 -10 days in hospital. The major complications (all very uncommon) following this are; dislodgement of clots in the aneurysm to the legs with possible later amputation; paraplegia from clamping spinal cord blood supply(<.001%); renal failure; gangrene of the colon.
The latest treatment advance has been the development of Endoluminal Grafting (ELG)( see picture on the left) which inserts a bypass graft supported by metal stents into the aneurysm via 2 small groin incisions using x-ray screening to place the graft correctly. This is a much lesser procedure, and is most appropriate for older sicker patients. The drawback is that it may be less effective at excluding the aneurysm, and further procedures may be necessary to stop "leaks" around the graft. Also not all patients are anatomically suitable for this procedure. The risks of renal failure, paraplegia and possible amputation of limbs are probably less common for the open operation, but it must be emphasized that they are all very uncommon. You need to know that they are possible, as you have to make an informed decision about your treatment.
Advantages of ELG:
Smaller procedure usually not requiring a general anaesthetic.
Shorter hospital stay (1-2 days)
Recovery quick with less pain (no abdominal incision).
No sexual dysfunction postoperatively (the abdominal operation may damage nerves controlling sexual function)
Disadvantages of ELG:
Relatively short worldwide follow-up to date (about 15 years) so unknown longer results. Some studies however are showing that this is a safe and effective way to manage aortic aneurysm disease.
Need to follow up for the rest of the patient's life by means of 6 to 12 monthly scans to detect the development of leaks, migration of the device, continued aneurysm expansion, breakage of metal struts.
Possible need for a subsequent procedure. The incidence of this in my hands is low (<5%)
For more information, see the following animation of the insertion of an endoluminal graft.
How do we decide what operation to perform?
Once you have undergone the appropriate tests to evaluate your aneurysm, we will sit down and talk to you about the possible options for operation. The traditional ("open") repair may be recommended if the aneurysm morphology is deemed not suitable for safe endovascular repair. If your aneurysm has the suitable morphology for endovascular repair we will discuss the options with you and decide on the appropriate type of graft to use.