Background: Despite successful percutaneous coronary intervention (PCI), patient s with non-ST-segment elevation myocardial infarction (NSTEMI) remain at risk of major adverse cardiovascular events (MACE).The combined prognostic value of pericoronary fat attenuation index (FAI), a marker of coronary inflammation fr om coronary computed tomography angiography (CCTA), and angiography-derived microcirculatory resistance (AMR), a marker of microvascular dysfunction, is un derexplored.Methods: This retrospective cohort included 508 NSTEMI patients who underwe nt successful PCI after pre-procedural CCTA.FAI and AMR were measured.The primary endpoint was MACE during follow-up.Sensitivity analyses using 1-year and 2-year time-restricted endpoints were performed to validate the robustness o f the findings.Cox regression and machine learning models were used.Mediatio n analysis assessed the pathway from FAI to outcomes via AMR.Results: Over a median follow-up of 620 days, MACE occurred in 146 patients (28.7%).High FAI (hazard ratio HR 1.03, P<0.001) and high AMR (HR 1.75, P<0.001) were independent predictors.The combined "High AMR/High FAI" phe notype had the highest risk.The FAI-AMR model improved prediction over a ba seline clinical model (C-index increase =0.055,net reclassification improvement NRI=0.809,integrated discrimination improvement IDI=0.139,all P<0.05).Exp loratory mediation analysis suggested that approximately 29.4% of the statistical J o u r n a l P r e -p r o o f Journal Pre-proof association between FAI and MACE was accounted for by AMR (P<0.001).Conclusion: FAI and AMR are independent and complementary predictors of pos t-PCI MACE in NSTEMI.Their combined assessment identifies a high-risk phen otype and adds prognostic value.Microcirculatory dysfunction partially mediates t he link between inflammation and outcomes, suggesting potential therapeutic targ ets.
Jiang et al. (Sun,) studied this question.