الفهرس 
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Abstract
The term aneurysm is derived from the Greek word aneurysma, meaning a “widening”. By current reporting standards, an aneurysm is defined as a permanent localized dilatation of an artery, having at least a 50% increase in diameter compared with the expected normal diameter. Arterial dilatation less than 50% of normal is termed ectasia. Normal diameter depends on age, gender, body size, and other factors.
AAAs is the most common type of aneurysm disease and because AAAs causes the greatest disability to the population with high risk of rupture, AAAs are largely a disease of elderly white men. They increase steadily in frequency after age of 50, are two to six times more common in men than in women, and are two to three times more common in white men than in black men.
Classically, abdominal aortic aneurysms (AAAs) have been attributed to a weakening of the arterial wall as a result of atherosclerotic vascular disease caused by the atheromatous lesions seen on pathologic examination. Recent evidence supports a multifactorial process in which atherosclerosis is involved. Other etiologic cofactors under investigation include changes in the matrix of the aortic wall with age, proteolysis, metalloproteinase changes, inflammation, infectious agents (eg, syphilis, mycotic infections), and a genetic predisposition (eg, Marfan syndrome, Ehlers-Danlos syndrome).
A significant increase in the incidence of asymptomatic AAAs has been noted in recent years, in part because of increased case finding as a result of more frequent use of ultrasonography and other abdominal imaging modalities.
An abdominal aortic aneurysm occurs most commonly in older individuals (between 65 and 75), and more in men and smokers. Most AAAs are asymptomatic, which leads to difficulty in their detection. Occasionally, patients may describe a “pulse” in their abdomen or may palpate a pulsatile mass.
The most important complication of an abdominal aortic aneurysm is rupture, which is most often a fatal event. An abdominal aortic aneurysm weakens the walls of the blood vessel, leaving it vulnerable to bursting open, or rupturing, and spilling large amounts of blood into the abdominal cavity.
Preoperative imaging is very important because patient selection and sizing of the endograft depend on it. Contrast enhanced, Spiral and Multislice computed tomography (CT) are the preferred initial methods for investigation. Anatomic inclusion criteria for endovascular AAA repair relate to the following issues:
(1) Suitability of the proximal and distal attachment sites.
(2) Adequacy of the access arteries.
(3) The presence of side-branches of the aortoiliac segment to be excluded from the systemic circulation.
In the early 1990s, Volodos in the Ukraine and Parodi, Palmaz, and Barone in Argentina introduced a less invasive endovascular method for AAA repair. Overtime, these pioneering devices were improved, and Commercial development of the technology has meant that the technique has spread worldwide. Briefly, the endovascular aneurysm repair (EVAR) procedure can be done percutaneously but usually consists of two small incisions in the groin to expose the femoral arteries. The sheathed Dacron or PTFE (polytetrafluoroethylene) graft and stents are fed through these arteries with catheters and guidewires until the graft is positioned correctly at the top and bottom of the aneurysmal segment of aorta.
Endovascular abdominal aortic aneurysm repair (EVAR) has become an alternative to traditional open repair for treating abdominal aortic aneurysms (AAAs), Suitability for EVAR is primarily determined through an analysis of the vascular morphology as represented by imaging studies.
Food & Drug Administration (FDA)-approved four endovascular stent graft devices in EVAR:
(A) AneuRx device
(B) The Gore Excluder
(C) The Zenith device
(D) Powerlink system (Endologix).
Emergency endovascular repair of acute symptomatic or ruptured AAA has received little attention compared with the immense interest in EVAR for elective AAAs.
The conclusion is to increase the background of knowledge about recent endovascular abdominal aortic aneurysm repair (EVAR) technique which is a very strong weapon with vascular surgeons against the aortic aneurysm and a very suitable alternative for the classical open repair technique especially with old high risk patients for surgical intervention.