What is an Abdominal Aortic Aneurysm?

An abdominal aortic aneurysm is a permanent localized dilatation of the abdominal aorta.

What is the Pathology of an Abdominal Aortic Aneurysm?

The pathology of an abdominal aortic aneurysm is:

-Definition: An abdominal aortic aneurysm is an abnormal dilation or bulging of the abdominal aorta, the major blood vessel supplying blood to the lower part of the body.

-Etiology: The most common cause of abdominal aortic aneurysm is atherosclerosis, a condition where fatty deposits build up in the arteries, weakening the vessel wall. Smoking, hypertension, advanced age, and a family history of abdominal aortic aneurysm are common risk factors.

-Genes involved: There is evidence suggesting a genetic predisposition, as aortic abdominal aneurysms tends to run in families. Specific genes involved in abdominal aortic aneurysm development are still under investigation.

-Pathogenesis: The sequence of events that lead to the abdominal aortic aneurysm involves atherosclerotic changes and hemodynamic stress. Atherosclerosis leads to the accumulation of plaque in the arterial wall, causing inflammation and weakening of the vessel. The weakened vessel wall is more prone to dilation due to the hemodynamic stress (constant pressure) of blood flow.

-Morphology: The morphology associated with abdominal aortic aneurysm shows dilated blood vessels that are more than 30 mm.

-Histology: Microscopic examination reveals the presence of atherosclerotic plaques, inflammation, and thinning of the arterial wall.

Abdominal Aortic Aneurysm. An aortic aneurysm as seen on CT with a small area of remaining blood flow James Heilman, MD - Not altered. CC BY-SA 4.0
Abdominal Aortic Aneurysm. Abdominal aortic aneurysms (3.4 cm) Intermedichbo at Serbian Wikipedia Abdominal aortic aneurysm 34 мм, Author: Milorad Dimic MD, Nis, Srbia, 2009. Not altered. CC BY-SA 3.0 rs
Abdominal Aortic Aneurysm. The faint outline of the calcified wall of an AAA as seen on plain X-ray James Heilman, MD - Not altered. CC BY-SA 3.0
Abdominal Aortic Aneurysm. 3D reconstruction of CT scan of infrarenal abdominal aortic aneurysm Bakerstmd - Not altered. CC BY-SA 4.0
Abdominal Aortic Aneurysm. An axial contrast-enhanced CT scan demonstrating an abdominal aortic aneurysm of 4.8 by 3.8 cm James Heilman, MD - Not altered. CC BY-SA 3.0
Abdominal Aortic Aneurysm. Sagittal CT image of an AAA. Not altered. Public Domain
Abdominal Aortic Aneurysm. A ruptured AAA with an open arrow marking the aneurysm and the closed arrow marking the free blood in the abdomen James Heilman, MD - Not altered. CC BY-SA 3.0
Abdominal Aortic Aneurysm. Aortic measurement on abdominal ultrasonography in the axial plane between the outer margins of the aortic wall. Mikael Häggström, M.D. Not altered. CC0
Abdominal Aortic Aneurysm. Abdominal aortic aneurysm location Bruce Blaus - Not altered. CC BY-SA 4.0
Abdominal Aortic Aneurysm. The preoperative CTA. (A) Imminent rupture of the abdominal aortic aneurysm, with an aneurismal neck length of 3.4 mm and exudation near the aneurismal neck (white arrow in A). Preoperative measurement of the positions of the superior mesenteric artery (B) and bilateral renal arteries (C, D) was conducted by means of clock-face orientation. Preoperative digital subtraction angiography (DSA) (E) revealed an abdominal aortic aneurysm with hostile neck anatomy. Endovascular repair of the abdominal aortic aneurysms was carried out with the reconstruction of the mesenteric artery using a balloon-expandable stent (Scuba, InvatecS.pA, Italy) (white arrow in F). After the reconstruction of the right renal artery using a balloon-expandable stent (Paramount Mini GPS; ev3 Inc.) (white arrowhead in Fin F), a dissection of the left renal artery was found. The stent graft (Viabahn; WL Gore & Associates, Inc., Flagstaff, AZ) and self-expanding stent (Zilver, Cook Ireland Ltd., Limerick, Ireland) were used to extend into the left renal artery (black arrow in F). The postoperative DSA (F) showed that the blood flow of bilateral renal arteries was smooth. CTA = computed tomographic angiography, DSA = digital subtraction angiography. Application of physician-modified fenestrated stent graft in urgent endovascular repair of abdominal aortic aneurysm with hostile neck anatomy. Medicine. Not altered. CC.

How does an Abdominal Aortic Aneurysm Present?

Incidence and Prevalence: Abdominal aortic aneurysm is more common in older adults, especially men. The incidence increases with age.

Typical Age: Most abdominal aortic aneurysm cases are diagnosed in individuals over the age of 65.

Symptoms: Abdominal aortic aneurysm is often asymptomatic, but as it enlarges, it may cause abdominal or back pain. In severe cases, rupture can lead to a medical emergency.

Clinical Findings: Pulsatile abdominal mass, abdominal tenderness, and in severe cases, signs of shock if there is rupture.

Patients with abdominal aortic aneurysms are typically males in the age range of around 60-years-old. The symptoms, features, and clinical findings associated with abdominal aortic aneurysm include lower leg tingling, and abnormal abdominal sounds.

How is an Abdominal Aortic Aneurysm Diagnosed?

An abdominal aortic aneurysm is diagnosed by imaging studies.

Imaging Studies: Abdominal ultrasound, CT scan, or MRI are commonly used to visualize the aorta and confirm the diagnosis.clinical presentation, physical examination, and ultrasound.

Screening: Ultrasound screening is recommended for certain high-risk populations, such as older men who have a smoking history.

How is an Abdominal Aortic Aneurysm Treated?

An abdominal aortic aneurysm is treated based on the size. They are either monitored or surgically repaired.

Monitoring: Small abdominal aortic aneurysms may be monitored regularly, especially in individuals with no symptoms.

Surgical Repair: Larger abdominal aortic aneurysms or those at risk of rupture may require surgical intervention, such as open surgery or endovascular repair using stent grafts.

What is the Prognosis of an Abdominal Aortic Aneurysm?

The prognosis of an abdominal aortic aneurysm is poor if diagnosed late due to the high chances of rupture, but it has a good prognosis after treatment if diagnosed early.

Rupture Risk: The main concern is the risk of rupture, which can be life-threatening. The risk increases with the size of the aneurysm.

Surgical Outcome: Surgical repair is generally successful, and the prognosis improves with early detection and intervention.

Survival Rates: Mortality rates are higher for ruptured abdominal aortic aneurysm, emphasizing the importance of timely diagnosis and intervention.

Anyone experiencing symptoms or at risk for abdominal aortic aneurysm should seek prompt medical attention. Regular check-ups and screening, especially for high-risk individuals, contribute to early detection and improved outcomes.