Analysis of coronary computed tomography angiography-derived pericoronary fat attenuation index characteristics in the diagnostic assessment of patients with Takayasu arteritis

Background: The clinical value of pericoronary adipose tissue in assessing Takayasu arteritis (TAK) with coronary artery involvement (CAI) is yet to be determined. The purpose of this study was to investigate the characteristics of pericoronary fat attenuation index (FAI) derived from coronary computed tomography angiography in patients with TAK. Methods: This is a retrospective study involving enrollment of 111 consecutive patients ( mean age, 33.92 +/- 12.48 years) who were diagnosed as TAK, of which 52 patients had coronary artery involvement (TAK-CAI) and 59 patients without coronary artery involvement (TAK-nonCAI). Based on the extent of coronary artery lesion, the TAK-CAI group was further classified into localized group ( n=25) and diffused group (n=27). Furthermore, patients with TAK were divided into active group (n=33) and inactive group ( n=78). Meanwhile, 51 gender-matched individuals with normal appearance in coronary computed tomography angiography examination were enrolled as the control group. The pericoronary FAI was quantitatively evaluated on each coronary computed tomography angiography examination groups. The diagnostic value of pericoronary fat attenuation index was determined using the area under the curve (AUC) of the receiver operating characteristic. Results: A higher pericoronary FAI was found in TAK-nonCAI group than control group with normal coronary arteries (P<0.001). Multivariate analysis showed that the FAI is an independent risk factor for coronary involvement in TAK patients [odds ratio: 1.23, 95% confidence interval (CI): 1.13-1.35, P<0.001]. With the best cut-off value of -86.50, the pericoronary FAI identified coronary involvement with 67.8% sensitivity and 74.5% specificity (AUC: 0.794, 95% CI: 0.713-0.875, P<0.001). Multivariate analysis showed that the pericoronary FAI is an independent risk factor for determination of active TAK patients (odds ratio: 1.57, 95% CI: 1.25-1.97, P<0.001). With the best cut-off value of -79.50, the pericoronary FAI identified active inflammation with 93.9% sensitivity and 74.4% specificity (AUC: 0.911, 95% CI: 0.860-0.962, P<0.001). Conclusions: Coronary computed tomography angiography-derived fat attenuation index is significantly increased in patients with TAK and can be used as a reliable biomarker to distinguish TAK patients from those with normal coronary arteries, and determine the extent of TAK inflammation.