Response to ‘Prognostic value of lesion-specific pericoronary adipose tissue attenuation? Importantly, but not yet!’

We appreciate the insightful comments by Du et al. regarding our study on the long-term prognostic value of lesion-specific pericoronary adipose tissue (PCAT) attenuation. Du et al. highlight considerations regarding the methodology employed in our analysis, and stimulate discussion on the assessment of PCAT attenuation. In our study,1 including 483 patients and 1561 coronary lesions, we measured PCAT attenuation per lesion using coronary computed tomography angiography (CCTA). Prior studies assessing PCAT have used various methodologies, since a gold standard has not been established for the measurement of PCAT. One approach focuses on the proximal segment of the right coronary artery, since this segment has minimal anatomical variations, absence of side branches, and more adipose tissue compared to the left anterior descending artery and left circumflex artery.2 This methodology has been expanded in other studies3,4 by including the proximal segments of all three epicardial coronary arteries, since differences in PCAT attenuation among the different coronary arteries have been observed, along with the varying prognostic significance of PCAT of the three coronary arteries. Moreover, various studies have shown that PCAT attenuation changes in highly inflamed regions such as ruptured plaque or spontaneous coronary dissections.3 In addition, significant differences between culprit and non-culprit lesions have been demonstrated,5,6 supporting the concept that focal PCAT assessment can provide valuable insights. This lesion-specific approach allows evaluation of lesion-related features, including high-risk plaque characteristics and plaque composition. Moreover, it is worth considering whether it is meaningful to measure proximal PCAT in patients with only mid and/or distal disease.