What is an aneurysm?
An aneurysm is a dilation in a portion of the vasculature. It can be located either in an artery, a vein as well as in the heart. The most common site is the body which is aorta artery in the abdomen. This is called an AAA, an abdominal aortic aneurysm. However, an aneurysm in the brains is also common. After the rupture of such aneurysms often occur obvious symptoms, such as loss of function and severe headaches.
Once thought to hardening of the arteries (atherosclerosis) and cause an aneurysm. However, this is not the sole cause, there are probably other factors are of importance for the development of an aneurysm. Nowadays it is a degenerative process in the wall of the aorta seen as a cause. Here the balance is disturbed between proteins that build the aortic wall and others break it. Can also hereditary disorders in the structure and firmness of the vascular wall, leading to the formation of aneurysms at an early age. In addition to deviations in structure and strength of the vascular wall may also play a role in certain inflammatory responses. Furthermore, smoking causes wear of the veins. Smokers run a significantly higher risk of an aneurysm than non-smokers, and if the aneurysm is growing - according to statistics - faster in smokers and ex-smokers than in nonsmokers.
Aneurysm symptoms
An aneurysm of the aorta in the abdomen or the abdominal aortic aneurysm has often without symptoms. People with a AAA, therefore, often do not know that they have an aneurysm. Sometimes symptoms as a pulsing sensation in the (top), or abdominal pain in the back, by pressing of the aneurysm on the spine, is described. In the majority of cases found AAA is an incidental finding in radiological studies for another indication (such as an ultrasound of the heart or CT scan of the kidneys). If the size increases from the aneurysm, this also increases the risk of cracking increased. The vessel is weaker and may form a crack. This is a life threatening situation, where there is bleeding from a lack of circulating blood can occur with tissue / organ damage and even death. A rupture of the aneurysm is difficult to recognize, but alarms are fainting / pallor and acute pain in the abdomen or lower back. When the rupture of the aorta in the abdomen is that bleeding in 75% of the cases lethal. More than 50% of patients dies before arriving at the hospital, and another more than 50% of the patients operated dies during surgery. A rupture in the thorax (chest cavity) is almost always fatal.
Heredity
There is probably some form of inheritance, as it is more common in some families. Literature indicates that approximately 25% of people with an AAA also has one or more affected first-degree relatives. Siblings of aneurysm patients let themselves often preventive examinations for symptoms of aneurysm.
Aneurysm treatment
Because of the dangers, it is advisable suspected an aneurysm to be examined properly. Physical examination alone never closes out an aneurysm. As gold standard abdominal ultrasound is used to detect an aneurysm. Here, one can accurately determine the correct diameter. It is essential that one hereby to measure the largest anteroposterior diameter (anterior-posterior or AP-diameter) persists. If arbitrary limit a diameter of 55 mm is used (in women 50 mm). Research has shown that this diameter the risk of rupture is real, and the risks of surgery do not outweigh the risk of rupture. A CT scan with contrast shows exactly how the vascular tree around the aorta looks. This also determines whether one laparotomisch (opening the abdominal cavity) or endovascularly (from the vessels in the femoral artery approach, after (s)) operates. They choose, respectively, for the inhechten of a aortabifurcatieprothese, also called pants prosthesis, or an endovascular stent as shown. The latter procedure is called also called EVAR; Endovascular Aneurysm Repair. A major complication of surgery are EVAR endoleaks. That is to say, as much as the leakage of blood through the prosthesis. Five types of endoleaks are distinguished:
Type 1; a leak where the stent is attached to the vessel
- 1a - proximal
- 1b - distal
- 1c - hider iliac artery
- 2a - single vessel
- 2b - involved two or more branches
- 3a - leakage between components of the stent
- 3b - fractures or holes in the stent
Type 5; increasing size of aneurysm sac without proving actual leak
Treatment rupture
At the moment that an aneurysm ruptures every minute counts. After making a CT scan is usually chooses the laparotomy procedure for inhechten of a pair of trousers prosthesis. A clear protocol and good cooperation of the emergency room, radiology department, the anesthesiologist, the vascular surgeon and the OR staff are essential to the survival of the patient. The perioperative mortality of ruptured AAA is very high, about 20% in the EVAR method and about 50% in the conventional open procedure.