Prognostic value of perivascular fat attenuation index. In the CRISP-CT study,¹⁴ which evaluated two prospective clinical cohorts of 3912 patients undergoing diagnostic coronary computed tomography angiography for clinical indications, perivascular fat attenuation index was predictive of cardiac mortality both in the derivation and validation cohorts (A, B). Fat attenuation index provided incremental prognostic value for cardiac mortality on top of traditional clinical risk factors, Duke coronary artery disease index and number of high-risk plaque features on coronary computed tomography angiography (C, D), (reproduced with permission from Oikonomou et al.  ¹⁴). High-risk plaque (HRP) features on coronary computed tomography angiography are defined as the napkin-ring sign (NRS), low attenuation plaque (LAP), spotty calcification (SC), and positive remodelling (SP) (E). Stratification of the pooled population of CRISP-CT based on the presence of high-risk plaque and high coronary inflammatory burden as determined by perivascular fat attenuation index and observed rates of cardiac mortality within each group (F, G). The combination of high-risk plaque and high fat attenuation index could be used to identify vulnerable patients at the highest risk that are eligible for aggressive prevention strategies; derived from post hoc data analysis of CRISP-CT data in the Oxford Academic Cardiovascular Computed Tomography (OXACCT) Core Lab.