Native myocardial longitudinal (T1) relaxation time: Regional, age, and sex associations in the healthy adult heart

• Published in: Journal of magnetic resonance imaging Vol. 44; no. 3; pp. 541 - 548
• Main Authors: Rauhalammi, Samuli M.O., Mangion, Kenneth, Barrientos, Pauline Hall, Carrick, David J.A., Clerfond, Guillaume, McClure, John, McComb, Christie, Radjenovic, Aleksandra, Berry, Colin
• Format: Journal Article
• Language: English
• Published: United States Blackwell Publishing Ltd 01.09.2016; Wiley Subscription Services, Inc; John Wiley and Sons Inc
• Subjects: Age; Aging - pathology; Aging - physiology; Cardiac Imaging Techniques - methods; Female; Gender differences; healthy volunteer; Heart Ventricles - anatomy & histology; Heart Ventricles - diagnostic imaging; Humans; longitudinal relaxation time; Magnetic resonance imaging; Magnetic Resonance Imaging - methods; Male; Middle Aged; myocardium; native T1; NMR; Nuclear magnetic resonance; Original Research; Reference Values; Regression analysis; Reproducibility of Results; Sensitivity and Specificity; Sex Characteristics; T1 mapping; Ventricular Function, Left - physiology; native T1; longitudinal relaxation time; healthy volunteer; myocardium; T1 mapping
• ISSN: 1053-1807; 1522-2586; 1522-2586
• DOI: 10.1002/jmri.25217

Purpose To use magnetic resonance imaging (MRI) at two field strengths to assess healthy adults' regional myocardial noncontrast (native) T1 relaxation time distribution, and global myocardial native T1 between sexes and across age groups. Materials and Methods In all, 84 healthy volunteers underwent MRI at 1.5T and 3.0T. T1 maps were acquired in three left ventricular short axis slices using an optimized modified Look–Locker inversion recovery investigational prototype sequence. T1 measurements in msec were calculated from 16 regions‐of‐interest, and a global T1 value from all evaluable segments per subject. Associations were assessed with a multivariate linear regression model. Results In total, 1297 (96.5%) segments were evaluable at 1.5T and 1263 (94.0%) segments at 3.0T. Native T1 was higher in septal than lateral myocardium (1.5T: 956.3 ± 44.4 vs. 939.2 ± 54.2 msec; P < 0.001; 3.0T: 1158.2 ± 45.9 vs. 1148.9 ± 56.9 msec; P = 0.012). Native T1 decreased with increasing age in females but not in males. Among lowest age tertile (<33 years) global native T1 was higher in females than in males at 1.5T (960.0 ± 20.3 vs. 931.5 ± 22.2 msec, respectively; P = 0.003) and 3.0T (1166.5 ± 19.7 vs. 1130.2 ± 20.6 msec; P < 0.001). No sex differences were observed in upper age tertile (≥55 years) at 1.5T (937.7 ± 25.4 vs. 934.7 ± 22.3 msec; P = 0.762) or 3.0T (1153.0 ± 30.0 vs. 1132.3 ± 23.5 msec; P = 0.056). Association of global native T1 to age (P = 0.002) and sex (P < 0.001) was independent of field strength and body size. Conclusion In healthy adults, native T1 values are highest in the ventricular septum. Global native T1 was inversely associated with age in women, but not in men. J. Magn. Reson. Imaging 2016;44:541–548.