Prognostic value of pericoronary adipose tissue attenuation in cardiovascular outcomes: a systematic review and meta-analysis.

BACKGROUND: Pericoronary adipose tissue (PCAT) attenuation has emerged as a novel imaging biomarker of coronary inflammation, reflecting dynamic perivascular changes. Elevated PCAT attenuation has been linked to adverse cardiovascular outcomes; however, its prognostic significance across diverse populations, coronary territories, and analytic methods remains unclear. To determine the prognostic value of PCAT attenuation for major adverse cardiovascular events (MACE) and mortality, and to identify potential effect modifiers through subgroup and meta-regression analyses. METHODS: This systematic review and meta-analysis followed PRISMA guidelines. PubMed, Cochrane Library, and Web of Science were searched through August 2025. Observational studies reporting associations between PCAT attenuation and cardiovascular outcomes were included. Hazard ratios (HRs) were pooled using random-effects models, and prespecified subgroup and meta-regression analyses were conducted to explore heterogeneity. RESULTS: Twenty-one studies encompassing 27 populations (17,160 patients) were analyzed. Elevated PCAT attenuation was significantly associated with MACE (HR 1.58; 95% CI: 1.38-1.81, p < 0.001), all-cause mortality (HR 1.77; 95% CI: 1.51-2.07, p < 0.001), and cardiac mortality (HR 2.25; 95% CI: 1.62-3.13, p < 0.001). Coronary territory-based analyses showed significant prognostic associations in the left anterior descending and right coronary arteries, whereas the association in the left circumflex artery was not statistically significant. Meta-regression identified Asian population (p = 0.015), measurement method (Caristo vs others; p < 0.001), and body mass index (p = 0.046) as modifiers; only measurement method remained significant (p = 0.021) in multivariable analysis. CONCLUSION: Higher PCAT attenuation is associated with an increased risk of cardiovascular events, particularly MACE. However, the magnitude of the association may be influenced by measurement methodology, small-study effects, and publication bias. Further prospective validation, methodological standardization, and evaluation of incremental prognostic value are needed before routine clinical implementation.