Assessment of late gadolinium enhancement peri-infarct zone in myocardial infarction with in vivo endogenous T1-rho mapping

Purpose To evaluate the diagnostic performance of endogenous T1ρ mapping, compared with native T1 and T2 mapping, for identifying late gadolinium enhancement (LGE)-defined peri-infarct zones in acute ST-elevation myocardial infarction (STEMI) and chronic myocardial infarction (MI). Methods This retrospective study included 35 patients with acute STEMI, 21 with chronic MI, and 35 healthy controls who underwent cardiac MRI with T1ρ, native T1, and T2 mapping between March 2022 and August 2025. LGE was used to delineate peri-infarct zones in patients with MI. A linear mixed-effects model accounting for within-participant clustering compared T1ρ values across myocardial segments. Receiver operating characteristic analysis was used to assess diagnostic performance. Results Among the 56 patients with MI (mean age, 57 ± 13 years; 49 men), global T1ρ values were elevated in both acute STEMI and chronic MI compared with controls (both p < 0.001). T1ρ values were higher in peri-infarct zones than in control myocardium (all p < 0.05). For discriminating peri-infarct zones from control myocardium in acute STEMI, T1ρ (AUC, 0.95) performed comparably to T2 (AUC, 0.97; p = 0.11) and better than native T1 (AUC, 0.88; p = 0.02). In chronic MI, T1ρ (AUC, 0.91) outperformed native T1 (AUC, 0.81; p = 0.04) and T2 (AUC, 0.68; p < 0.001). Conclusion Endogenous T1ρ mapping may provide a contrast-free biomarker for myocardial tissue characterization in MI, with diagnostic performance comparable to T2 in acute STEMI and superior to native T1 and T2 in chronic MI.