Association between Periaortic Adipose Tissue on Computed Tomography and Aortic Vulnerable Plaques Evaluated by Non-Obstructive General Angioscopy.

Periaortic adipose tissue (PAAT) is known to promote atherosclerosis and has been linked to cardiovascular disease (CVD). However, its association with aortic plaque instability remains unclear. This study aimed to assess whether PAAT is associated with aortic vulnerable plaques (VPs) as identified by non-obstructive general angioscopy (NOGA) in patients with CVD.We investigated 117 patients who underwent both aortic NOGA and computed tomography (CT). On CT images, adipose tissue was defined by Hounsfield unit values ranging from -190 to -30, from the level of the tracheal bifurcation to the diaphragm. The PAAT volume index (PAAT-I) was calculated by dividing PAAT volume by the body surface area. The number of VPs in the whole aorta was assessed using NOGA.The number of VPs in both the thoracic and the whole aorta was significantly correlated with PAAT-I (thoracic: r = 0.40, P < 0.0001; whole: r = 0.33, P = 0.007). In univariate Poisson regression, PAAT-I was significantly associated with the number of VPs in the thoracic aorta (β = 0.04, P < 0.0001). This association remained significant in multivariate analysis adjusted for age, sex, body mass index, smoking history, hypertension, dyslipidemia, diabetes mellitus, chronic kidney disease, peripheral artery disease, stroke, and epicardial adipose tissue volume index (β = 0.04, P = 0.005).PAAT in the thoracic aorta was related to the number of NOGA-derived aortic VPs in patients with CVD. PAAT may play a crucial role in the development of aortic plaque instability.