Cardiovascular disease remains the leading global cause of mortality, with inflammation now recognized as a central driver of atherosclerosis and other cardiometabolic conditions. Recent advances have repositioned perivascular adipose tissue from a passive structural element to an active endocrine and immunomodulatory organ, now a key focus in cardiovascular and metabolic research. Among the most promising tools for assessing perivascular adipose tissue inflammation is the fat attenuation index, a non-invasive imaging biomarker derived from coronary computed tomography angiography. This review explores the translational potential of the fat attenuation index for cardiovascular risk stratification and treatment monitoring in both coronary artery disease and systemic inflammatory or metabolic conditions (psoriasis, systemic lupus erythematosus, inflammatory bowel disease, obesity, type 2 diabetes, and non-obstructive coronary syndromes). We summarize evidence linking perivascular adipose tissue dysfunction to vascular inflammation and adverse cardiovascular outcomes. Clinical studies reviewing the fat attenuation index highlight its ability to detect subclinical inflammation and monitor treatment response. As research advances, standardization of measurement protocols and imaging thresholds will be essential for routine clinical implementation.