CT-Derived Aortic Plaque Characteristics Predict MRI-Detected Silent Cerebral Infarction after Total Aortic Arch Replacement.

Abstract

Purpose: Silent cerebral infarctions are common after aortic arch surgery; however, the predictive value of preoperative computed tomography (CT)-derived plaque characteristics remains unclear. We investigated the incidence, distribution, and risk factors for new cerebral infarction lesions (NCILs) after total aortic arch replacement (TAR), focusing on low-attenuation plaque (LAP, 0-60 Hounsfield units [HU], a surrogate of lipid-rich vulnerable plaque) burden.

Methods: Among 82 consecutive TAR patients, 41 underwent both pre- and postoperative brain diffusion-weighted magnetic resonance imaging (MRI). Clinical profiles, CT-derived atheroma grade and plaque attenuation, operative details, and outcomes were compared between NCIL-positive and NCIL-negative groups. The primary multivariable model simultaneously included arch atheroma grade and LAP area, adjusted for age and sex.

Results: NCILs were detected in 25/41 patients (61%): 23 silent and 2 symptomatic. All NCILs exhibited embolic imaging features without watershed or hypoperfusion patterns. NCIL-positive patients had significantly greater arch LAP area (63.9 vs. 17.7 mm², p <0.01). On multivariable analysis, arch LAP remained the only independent predictor (OR per 10 mm², 3.01; 95% confidence interval [CI] 1.50-8.75; p = 0.012), whereas atheroma grade was not.

Conclusion: More than half of TAR patients developed MRI-detected, predominantly silent NCILs. Preoperative arch LAP was the sole independent predictor. LAP assessment may refine intraoperative risk stratification and guide tailored neuroprotective strategies.