principally abdominal aortic aneury...

principally abdominal aortic aneurysms (AAAs) are asymptomatic, not detectable onward physical examination, and silent until discovered during radiologic testing for other reasons. Tobacco use, hypertension, a family history of AAA, and male sex are clinical risk factors for the unfolding of an aneurysm. Ultrasound, the preferr order of screening, is cost-effective in high-risk patients. Repair is indicated when the aneurysm becomes greater than 55 cm in diameter or advances more than 0.6 to 08 cm by means of year. Asymptomatic patients with an AAA should be medically optimized before repair, including institution of beta blockade. Symptomatic aneurysms not absent with back, abdominal, buttock, groin, testicular, or leg pain and require cogent surgical attention. Rupture of an AAA involves whole loss of aortic wall integrity and is a surgical crisis requiring immediate repair. The mortality rate approaches 90 percent if break occurs outside the hospital. Although make open surgical repair has been performed safely, an endovascular approach is used in picked patients if the aortic and iliac anatomy are amenable. sum of two units large randomized controlled trials did not find any improvement in mortality rate or morbidity with this approach compared with conventional render free of access surgical repair.

**********

Abdominal aortic aneurysm (AAA) is a relatively public and often fatal condition that primarily affects older patients. AAAs and aortic dissections are responsible for at least 15000 deaths yearly and in 2000 were the 10th leading cause of death in white men 65 to 74 years of age in the United States. (1) With an aging population, the incidence and prevalence of AAA is certain to rise. chiefly AAAs are asymptomatic, and physical examination lacks sensitivity for detecting an aneurysm. (2) It is important that family physicians understand which patients are at risk for the progressive growth of AAA and the appropriate evaluation formerly a patient has been diagnosed with an aneurysm.

Definition and Etiology

An aneurysm is a permanent focal dilatation of an artery to 15 times its normal diameter. The normal infrarenal aortic diameters in patients older than 50 years are 15 cm in women and 17 cm in men by way of convention, an infrarenal aorta 3 cm in diameter or larger is considered aneurysmal. (3)

The primary issue in the development of an AAA involves proteolytic degradation of the extracellular matrix proteins elastin and collagen. Various proteolytic enzyme including matrix metalloproteinases, are critical during the degradation and remodeling of the aortic wall. (4) Oxidative stres also plays an important character and there is an autoimmune constituent to the development of AAA, with extensive lymphocytic and monocytic infiltration with deposition of immunoglobulin G in the aortic wall. (4) Cigarette smoking elicits an increased inflammatory reply within the aortic wall. (5) An infectious etiology with Chlamydia pneumoniae has been propos still not proven. (4) Increased biomechanical wall stres also contributes to the formation and feud of aneurysms with increased wall tension and disordered arise in the infrarenal aorta. (4) Finally, 12 to 19 percent of first-degree relatives, predominantly men of a patient with an AAA will make known an aneurysm. (6)

Screening

Ultrasound is the standard imaging tool; if performed by the agency of trained personnel, it has a sensitivity and specificity approaching 100 and 96 percent respectively, for the detection of infrarenal AAA (7) (Figure 1) The U Preventive Services Task Force has released a statement summarizing recommendations for screening for AAA. (8) It stated that screening benefits patients who have a relatively high risk for dying from an aneurysm; major risk factors are age 65 years or older male sex and smoking at least 100 cigarettes in a lifetime. The guideline commits one-time screening with ultrasound for AAA in men 65 to 75 years of age who have at all times smoked. No recommendation was made for or against screening in men 65 to 75 years of age who have at no time smoked, and it recommended against screening women Men with a hardy family history of AAA should be cautioned about the risks and benefits of screening as they approach 65 years of age.

[FIGURE 1 OMITTED]

Clinical Evaluation

ASYMPTOMATIC PATIENTS

chiefly patients with AAA are asymptomatic. Typically, aneurysms are noted upon studies performed for other reasons, as oppos to during physical examination. In these patients, it is important to confirm that there is no evidence of significant back, abdominal, or groin pain.

The medical, social, and family history are important in determining if risk factors for exhibition expansion, and rupture of an aneurysm are at hand (Table 1 (6,9-14)). Previous abdominal operations can make explain AAA repair technically difficult and may necessitate a retroperitoneal approach instead of a transabdominal approach. A history of endovascular AAA repair also is important because AAA contention following endograft repair has been reported. (15) Aneurysms proximal and distal to a previous graft (eg synchronous AAA) also may offer and present as a pulsatile abdominal mass.