Advancing pericoronary inflammation evaluation: dual-energy CT-derived fat fraction as a promising imaging biomarker for cardiovascular risk stratification
Sara Marziali, Milan / Italy
Author Block: S. Marziali, C. B. Monti, D. Capra, F. Rizzetto, G. Folco, F. Sardanelli, F. Secchi; Milan/ITPurpose: The objective of this study is to assess the role of pericoronary fat fraction (FF) obtained via dual-energy CT as an innovative imaging biomarker to detect coronary inflammation, comparing it to conventional biomarkers such as pericoronary fat attenuation index (FAI) and the degree of coronary stenosis.Methods or Background: In our retrospective study, we reviewed patients who had undergone cardiac CT scans at our institution using a dual-energy calcium scoring scan. We collected both demographic and clinical data for each patient, including factors like family history of CAD, smoking habits, type 2 diabetes, hypertension, and hypercholesterolaemia. Our main objective was to evaluate fat fraction (FF), defined as the ratio of adipose tissue within a designated area: Each patient's FF maps were processed using the Syngo.via software, and regions of interest (ROIs) were delineated around the coronary arteries, specifically the left anterior descending artery (LAD), circumflex artery (CX), and right coronary artery (RCA). Concurrently, fat tissue attenuation (FAI) values were recorded. Information regarding coronary stenoses was extracted from CT reports for comprehensive analysis.Results or Findings: The study encompassed a sample of 99 patients, comprising 32% females with a median age of 66 years (IQR: 58-74 years). A significant negative correlation emerged between FF and FAI across coronary arteries: LAD at ρ=-- 617 (p<0.001), LCX at ρ=-0.493 (p<0.001), and RCA at ρ=−0.506 (p<0.001). Pericoronary FF displayed a weak negative correlation with coronary stenosis at the LAD (ρ=-0.220, p=0.035), correlations were not statistically significant for the LCX and the RCA (p=0.572).
Conclusion: Fat fraction, evaluated using dual-energy CT, presents promise as an additional imaging biomarker for coronary inflammation. It could yield potential for cardiovascular risk stratification, underscoring the need for further, comprehensive research.Limitations: This was single centre, retrospective study.Funding for this study: No funding was received for this study.Has your study been approved by an ethics committee? YesEthics committee - additional information: The local ethics committee (Ethics Committee of IRCCS Ospedale San Raffaele) approved this retrospective study (protocol code “CardioRetro”, number 122/int/2017; approved on 14th September 2017, and amended on 19th July 2022). Informed consent was waived due to the retrospective nature of the study.