A diameter of 50 or 55 mm is the primary clinical criterion for assessing abdominal aortic aneurysm (AAA) rupture risk. However, although larger diameters may induce higher rupture risk, not all AAAs exceeding intervention threshold will rupture, highlighting the need for indicators besides diameter to help rupture prediction and treatment of AAA ≥ 50 mm. The study aims to combine computation, experiment, and statistics to establish rupture prediction models for AAAs ≥ 50 mm and explore the optimal predictors of AAA rupture with different diameters by anatomical and hemodynamic characteristics. Through numerical simulation and in vitro experiment, morphological and hemodynamic parameters were obtained from 82 AAAs (41 ruptured) ≥ 50 mm. The results of significance test and logistic regression indicate that low time-averaged wall shear stress (TAWSS) of AAA and maximum diameter of common iliac artery, and high oscillatory shear index (OSI) of AAA, TAWSS of iliac artery and tortuosity of abdominal aorta increase rupture risk of AAA ≥ 50 mm. The prediction model combining these variables was established with high accuracy (area under curve = 0.978). Furthermore, univariable analyses for AAAs of different diameters imply the OSI is a risk factor for AAA rupture of 50–65 mm, while higher TAWSS decreases the risk of AAA rupture of 65–80 and ≥ 80 mm. The findings may contribute to accurate rupture prediction and personalized management of AAAs ≥ 50 mm and with different diameters, and further demonstrate potential value and application prospects of combining morphology and hemodynamics in clinical practice.
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