Aortic Aneurysm

Definition

Definition of Aortic Aneurysm
An aortic aneurysm is a general term for any swelling (dilation or aneurysm) of the aorta to greater than 1.5 times normal, usually representing an underlying weakness in the wall of the aorta at that location. While the stretched vessel may occasionally cause discomfort, a greater concern is the risk of rupture, which causes severe pain; massive internal hemorrhage; and, without prompt treatment, death occurs rapidly.

Symptoms

Symptoms of Aortic Aneurysm
Most intact aortic aneurysms do not produce symptoms. As they enlarge, symptoms such as abdominal pain and back pain may develop. Compression of nerve roots may cause leg pain or numbness. Untreated, aneurysms tend to become progressively larger, although the rate of enlargement is unpredictable for any individual. Rarely, clotted blood which lines most aortic aneurysms can break off and result in an embolus. They may be found on physical examination. Medical imaging is necessary to confirm the diagnosis. Signs may include: anxiety or feeling of stress; nausea and vomiting; clammy skin; rapid heart rate.

In patients presenting with aneurysm of the arch of the aorta, a common sign is a hoarse voice as the left recurrent laryngeal nerve (a branch of the vagus nerve) is stretched. This is due to the recurrent laryngeal nerve winding around the arch of the aorta.

Causes

Causes of Aortic Aneurysm
The wall of the aorta is normally very elastic. It can stretch and then shrink back as needed to adapt to blood flow. But some medical problems, such as high blood pressure and atherosclerosis (hardening of the arteries), weaken the artery walls. These problems, along with the wear and tear that naturally occurs with aging, can result in a weak aortic wall that bulges outward.

Diagnosis

Diagnosis of Aortic Aneurysm
Aneurysms are often diagnosed by chance during exams or tests done for other reasons. In some cases, they are found during a screening test for aneurysms. Screening tests help your doctor look for a certain disease or condition before any symptoms appear.

Treatment

Treatment of Aortic Aneurysm
Surgery is the definite treatment of aortic aneurysm, while medical therapy is typically supportive.

1. Surgery: The definitive treatment for an aortic aneurysm may be surgical or endovascular repair. The determination of surgical intervention is complex and determined on a per-case basis. Risk of aneurysm rupture is weighed against procedural risk. The diameter of the aneurysm, its rate of growth, the presence or absence of Marfan Syndrome, Vascular Ehlers-Danlos or similar connective tissue disorders, and other co-morbidities are all important factors in the overall treatment.
2. Open: Open surgery typically involves dissection of the dilated portion of the aorta and insertion of a synthetic (Dacron or Gore-Tex) patch tube. Once the tube is sewn into the proximal and distal portions of the aorta, the aneurysmal sac is closed around the artificial tube. Instead of sewing, the tube ends, made rigid and expandable by nitinol wireframe, can be much more simply, quickly and effectively ("airtight" seal) inserted into the vascular stumps and there permanently fixed by external ligature; different versions of the device were devised for the first (type I) and the second (type II) either distal or proximal aortic anastomosis (video). A new version of the expandable anastomotic device (type III) was more recently realized allowing to include the concavity of the aortic arch thus realizing at once distal anastomosis and dacron double strip buttressing with "airtight" dissected layers approximation. Modified type I expandable devices can be used to quickly connected the supraoertic trunks to the main tube graft when the entire aortic arch needs to be substituted.
3. Endovascular: In the recent years, the endoluminal treatment of abdominal aortic aneurysms has emerged as a minimally invasive alternative to open surgery repair. The first endoluminal exclusion of an aneurysm took place in Argentina by Dr. Parodi and his colleagues in 1991. The endovascular treatment of aortic aneurysms involves the placement of an endo-vascular stent via a percutaneous technique (usually through the femoral arteries) into the diseased portion of the aorta. This technique has been reported to have a lower mortality rate compared to open surgical repair, and is now being widely used in individuals with co-morbid conditions that make them high risk patients for open surgery. Some centers also report very promising results for the specific method in patients that do not constitute a high surgical risk group.

Prognosis

Prognosis of Aortic Aneurysm
Consult with your doctor.

Prevention

Prevention of Aortic Aneurysm
Attention to patient's general blood pressure, smoking and cholesterol risks helps reduce the risk on an individual basis. There have been proposals to introduce ultrasound scans as a screening tool for those most at risk: men over the age of 65. The tetracycline antibiotic Doxycycline is currently being investigated for use as a potential drug in the prevention of aortic aneurysm due to its metalloproteinase inhibitor and collagen stabilising properties.