Age-, sex-, and segment-specific myocardial T1 and T2 reference values in a healthy cohort: a prospective single-center study.
AIMS Accurate age- and sex-specific T1 and T2 reference values are critical for differentiating myocardial pathologies, yet existing data are inconsistent due to methodological variability. This study proposes standardized T1 and T2 mapping protocols with clinically feasible breath-hold durations and reports site-, sequence-, age-, sex-, and segment-specific reference values. METHODS AND RESULTS This prospective, single-center study enrolled 183 healthy Caucasian subjects (median age 34 y [IQR 22, 50], range 11-70 y, 98 females) who underwent both global and AHA segment-based native T1 and T2 mapping at 3 T. T1 was assessed using Modified Look-Locker Inversion-Recovery sequence, MOLLI 5s(3s)3s, while T2 was performed using a gradient spin-echo (GraSE) protocol with echo-planar-imaging readout. Assessment of T1 and T2 relaxation times was highly reproducible, with low intra- and interobserver, scan-rescan, and test-retest variability. Mean global T1 was 1238 ± 28 ms, and median global T2 was 45.4 ms [44.3, 46.8]. T1 was significantly higher in women than in men (1245 ± 28 ms vs. 1230 ± 7 ms, P < 0.001), while T2 did not differ significantly (45.3 ms [44.2, 46.6] vs. 45.6 ± 2.2 ms, P = 0.453). Segmental analysis showed higher T1 and T2 values in the septum than in the lateral wall (P < 0.005). Subtle associations of age with T1 and T2 were observed. CONCLUSION This single-center study supports the use of sex- and segment-specific reference values for standardized T1-MOLLI and T2-GraSE mapping at 3 T to facilitate the characterization of myocardial pathologies, while age seems to be negligible.