Heart transplantation is the ultimate treatment for end-stage heart failure, significantly extending life expectancy. However, long-term outcomes are limited by cardiac allograft vasculopathy (CAV) and allograft rejection (AR) despite advances in immunosuppression [1–3]. Endomyocardial biopsy (EMB) and invasive coronary angiography (ICA) remain the gold standard for evaluating AR and CAV, respectively [4]. However, both are invasive, carry procedural risks, and exhibit limitations in sensitivity…