Correlation Between Fat Attenuation Index and Plaque Parameters in Coronary CT Angiography: An Observational Study in Stable Coronary Artery Disease

BackgroundThe purpose of this prospective observational study was to predict plaque vulnerability, stenosis, and hemodynamic problems based on coronary CT angiography (CCTA) using the Fat Attenuation Index (FAI) as a marker.MethodsPatients with stable coronary artery disease (CAD) who underwent CCTA between January 2021 and January 2023 were included in this study. Data on basic patient information, plaque parameters, and Fractional Flow Reserve (FFR) were collected and analyzed. Multiple linear analysis was performed to explore the association between FAI and FFR. Additionally, regression models were developed to predict dependent variables such as FFR, plaque vulnerability, and the degree of stenosis based on FAI values. We also explored specific thresholds of FAI to classify plaques into vulnerable and non-vulnerable categories.ResultsA total of 62 patients with 84 coronary arteries were included in the final analysis. Based on FAI levels, the study subjects were divided into FAI-negative group (FAI ≤ -70.1 HU, 52 cases) and FAI-positive group (FAI > -70.1 HU, 32 cases). Patients in the FAI-positive group had significantly lower FFR values compared to those in the FAI-negative group, and the proportion of vulnerable plaques was significantly higher in the FAI-positive group. Furthermore, as the degree of stenosis observed on CCTA increased, FAI values showed a significant increase. Analysis of plaque types revealed that FAI in vulnerable plaques was significantly higher than in other plaque types. In the multiple linear analysis, lesion length, TPB and FFR was negatively correlated with FAI (β = -0.25, -0.13 and -41.72).ConclusionThe results support the use of FAI as a valuable tool in clinical practice. Its predictive capabilities regarding hemodynamic dysfunction and plaque susceptibility make it an essential component of modern cardiovascular risk assessment strategies.