Relationship between the abdominal aortic diameter and carotid atherosclerosis in middle-aged patients without established atherosclerotic cardiovascular diseases.

BACKGROUND

The purpose of our research was to study the relationship between the diameter of abdominal aorta (AA) and subclinical atherosclerosis in patients without established atherosclerotic cardiovascular diseases (ASCD) in the absence of pathological enlargement of AA.

METHODS

The study included 136 patients (52.9% male, 47.1% female), median age was 51.0 (45.5; 58.0) years. The maximum diameter of AA was measured in the infrarenal region at a level between the place of origin of the lower renal artery and bifurcation in cross section. Measurement of the anteroposterior diameter of AA was carried out from the outer-to-outer edge (OTO). Also, we determined the Aortic Size Index (ASI) with respect to body surface area (BSA), using the values of BSA obtained by five different formulas validated for use in clinical practice. All patients underwent carotid duplex ultrasound scanning with assessment of degree of carotid stenosis (according to ECST criteria).

RESULTS

An increase in the anteroposterior diameter of AA was directly correlated with maximum stenosis of carotid arteries (r=0.186; P=0.030). According to the results of a logistic regression analysis an increase in the diameter of AA by 1 mm was associated with an increase in the relative risk of carotid stenosis ≥50% by 1.37 times (95% CI: 1.01-1.85; P=0.041) after adjustment. Thus, an increase in diameter of AA of more than 1.75 cm with a sensitivity of 71.4% and a specificity of 73.0% made it possible to predict the presence of stenosis of the carotid arteries ≥50%. An increase in ASI<inf>Boyd</inf> (BSA was calculated using Boyd's formula) of more than 0.84 allowed predicting the presence of stenosis of the carotid arteries ≥50% with a sensitivity of 85.7% and a specificity of 65.6%.

CONCLUSIONS

In middle-aged patients without established ASCD, the diameter of AA and ASI directly correlated with the degree of carotid stenosis (according to ECST criteria). The diameter of AA and ASI demonstrated good sensitivity and specificity for the presence of asymptomatic carotid stenosis of ≥50%.