An aneurysm is an abnormal, localized expansion of a blood vessel, usually an artery, due to a birth defect or weakness in the wall of the vessel. The aneurysm may be spindle-shaped, which affects the entire circumference of a vessel segment, and results in a diffuse dilated lesion. The other type of aneurysm is saccular which involves only a portion of the circumference, and resembles a bag or pouch. Aortic aneurysms are usually located below the renal arteries and may extend into one or both iliac arteries.

Arteriosclerosis is most commonly associated with aneurysms. This disease may cause the vessel to weaken and the wall to expand. A familial occurrence in 20% of patients suggests a hereditary basis. Less frequent causes may be: trauma, arteritis, and mycotic infections. Contributing factors to this process are cigarette smoking and hypertension.

Aneurysms may become very large and rupture before any early symptoms develop. Usually, there is a steady, deep pain in the lumbosacral region, and an awareness of prominent abnormal abdominal pulsations. Because of compression from the aneurysm, formation of emboli may occur. If an aneurysm leaks blood, there will be local tenderness and acute pain. A bruit is usually heard over the aneurysm.

Often, the aneurysm is found on routine examination, or incidentally with an x-ray or ultrasound. However, 25% of x-rays will not reveal this condition because of lack of calcification in the mass. Abdominal ultrasound can detect the dimensions of the aneurysm, and may detect a thrombus. Because of the risk of complications, such as bleeding, an abdominal aortogram is not done until surgery is planned. Computed tomography (CT) scan and magnetic resonance imaging (MRI) are non-invasive and are now the desired standard for determining the size and location of abdominal aneurysms.

Resection of the aneurysm and grafting are indicated when the size of the aneurysm is 5 cm or greater. Surgery will take place sooner if the aneurysm is symptomatic or rapidly expanding. This surgery is best performed when it is not an emergency and there is time to evaluate the cardiac and general medical condition preoperatively.

Any aneurysm over 5 cm has a 20 to 40% chance of rupturing in five years or less. A planned aortic resection carries less morbidity (1 to 2%), whereas an acute rupture that requires emergency surgery has a mortality rate of over 50%.

• May be entitled to special monthly compensation where the Veteran has a single service-connected disability rated as 100% with additional service-connected disability or disabilities independently ratable at 60% or more, which are separate and distinct from the 100% service-connected disability and involves different anatomical segments or bodily systems. See  38 CFR 3.350(i)(1) – Special Monthly Compensation (SMC).

• This disease, (condition), only in its active form , has a 3 year presumptive period and shall be granted service connection although not otherwise established as incurred in or aggravated by service if manifested to a compensable degree within the applicable time limits under38 CFR 3.307 following service in a period of war or following peacetime service on or after January 1, 1947, provided the rebuttable presumption provisions of 38 CFR 3.307 are also satisfied. [38 CFR 3.309 [Disease subject to presumptive service connection], 38 CFR 3.309 (a). [chronic disease].

Notes

• The rating criteria for cardiovascular conditions underwent full-scale revision effective on November 14, 2021 and January 12, 1999.  A regulatory change was effective August 13, 1998, updated criteria for cold injury residuals under 38 CFR 4.104, DC 7122.  The changes are not considered liberalizing and should not be used as the basis for reduction unless the disability has actually improved.