Is abdominal plaque a common finding in abdominal arteries?

Is Abdominal Plaque a Common Finding?

Yes, atherosclerotic plaque in the abdominal aorta and its branches is a very common finding, particularly in older adults and those with cardiovascular risk factors.

Prevalence of Abdominal Arterial Atherosclerosis

Atherosclerotic obstruction of the abdominal arteries is present in 6% to 10% of unselected autopsies and in 14% to 24% of patients undergoing abdominal arteriography 1. This high prevalence stands in stark contrast to the rarity of symptomatic disease, reflecting the extensive collateral circulation in the abdominal vasculature 1.

In a computed tomography angiography (CTA) study of 261 patients with a mean age of 53 years, 69.3% had atherosclerotic plaques in the abdominal aorta or its branches 2. The prevalence increased significantly with age 2.

Distribution and Characteristics

Location Patterns

• The distal abdominal aorta is the most commonly affected site, followed by the common iliac arteries 2
• Atherosclerotic lesions typically occur at the origins of intestinal arteries from the aorta, representing protruding aortic plaques rather than isolated branch vessel disease 1
• The aortic bifurcation is the most frequent location for plaques at branching points, found in 41.8% of patients 2

Plaque Composition

The types of plaques found in abdominal arteries include 2:

• Mixed plaques (43%) - most common overall
• Calcified plaques (24%) - more common in branch vessels
• Soft plaques (3%) - least common

Clinical Significance Despite High Prevalence

The vast majority of patients with abdominal arterial atherosclerosis remain asymptomatic due to robust collateral networks 1. However, the presence of these plaques carries important clinical implications:

Association with Coronary Disease

Abdominal atherosclerotic lesions are highly associated with significant coronary artery disease, even in asymptomatic individuals 3. Specifically:

• Abdominal aortic stenosis <25% has an adjusted odds ratio of 3.37 for significant coronary stenosis 3
• Common iliac artery stenosis <25% has an adjusted odds ratio of 2.99 for coronary disease 3
• These associations increase dramatically with stenosis ≥25% (adjusted odds ratios of 16.39 and 7.32, respectively) 3

Risk for Infection

Damaged endothelium from atherosclerotic plaques or ulcers can be colonized during bacteremia, leading to infected atherosclerotic aneurysms or mycotic aneurysms 1. This is particularly relevant for Salmonella species, which have a predilection for infecting atherosclerotic vascular tissue through translocation from the gastrointestinal tract 1.

Risk Factor Associations

The presence and distribution of abdominal plaques correlate with specific risk factors 4:

• Aortic plaques: associated with age, smoking, elevated blood glucose, and hypertension
• Femoral artery plaques: associated with age, smoking, hypertension, and LDL cholesterol
• Carotid plaques: associated with total and LDL cholesterol

Common Pitfalls

Do not assume that incidentally detected abdominal atherosclerosis is clinically insignificant 3. While most patients remain asymptomatic for mesenteric ischemia, these findings warrant:

• Evaluation for coronary artery disease, particularly when stenosis ≥25% is present 3
• Assessment and modification of cardiovascular risk factors 4
• Awareness of increased infection risk during bacteremic episodes 1

The extent of arterial territory involvement correlates with coronary stenosis risk (P for trend <0.001) 3, making comprehensive evaluation of the abdominal vasculature clinically valuable beyond the immediate imaging indication.