AAA

Question 1

AAA: Definition

Answer 1

• Permanent pathological dilation of the aorta. More than 90% originate below the renal arteries
• Highest prevalence is in male smokers.

Question 2

AAA: Aetiology

Answer 2

• Traditionally, arterial aneurysms were thought to arise from atherosclerotic disease, and certainly intimal atherosclerosis reliably accompanies AAA.
• Subsequent data suggest that altered tissue metalloproteinases may diminish the integrity of the arterial wall.
• Smoking remains the most important risk factor

Question 3

AAA: Risk Factors

Answer 3

• Smoking remains the most important risk factor.
• hereditary/family history
• increased age
• male sex (prevalence)

Question 4

AAA: Pathophysiology

Answer 4

• Histologically there is obliteration of collagen and elastin in the media and adventitia
• smooth muscle cell loss with resulting tapering of the medial wall
• infiltration of lymphocytes and macrophages, and neovascularisation
• Proteolytic degradation of aortic wall connective tissue (matrix metalloproteinases (MMPs) and other proteases are derived from macrophages)

Question 5

AAA: Cinical manifestations: key presentations, other symptoms and signs

Answer 5

• Patients are usually asymptomatic and their abdominal aortic aneurysm is detected incidentally
• In the minority of patients who experience symptoms, abdominal, back, and groin pain are typical.
• Possible palpable pulsatile abdominal mass
• hypotension

Question 6

AAA: Investigations (diagnosis): 1st line, gold standard & other

Answer 6

• Ultrasound remains the definitive test for initial diagnosis and screening.
• Imaging with computed tomography angiography or magnetic resonance angiography is used for anatomical mapping to assist with operative planning.

Question 7

AAA: DDx

Answer 7

• Diverticulitis
• Ureteric colic
• Irritable bowel syndrome (IBS)

Question 8

AAA: Management

Answer 8

• For AAA detected as an incidental finding, surveillance is preferred to repair until the theoretical risk of rupture exceeds the estimated risk of operative mortality.
• Repair is indicated in patients with large asymptomatic AAA.
• Mortality during elective surgical repair is higher for women than men for both open repair (7.0% vs. 5.2%) and endovascular aneurysm repair (EVAR) (2.1% vs. 1.3%).