Abstract 13954: Myocardial T1 Mapping at 3 T: Reference Values and Influencing Factors

Abstract

Introduction: T1 mapping is a robust application to provide quantitative measurement reflecting myocardial properties. Knowledge of normal values for quantitative cardiovascular magnetic resonance (CMR) is crucial to distinguish normal from disease. Hypothesis: T1 mapping methods provide information of myocardial properties, in normal cohort, whether there is difference of myocardial tissue characterization in different gender, age remained unclear. Methods: 40 healthy volunteers (27 females; mean age 46±13 years) underwent left-ventricular (LV) T1 mapping in 3 short-axis slices at 3 T. For T1 mapping, a validated modified Look-Locker inversion recovery sequence was used before and after injection of gadolinium contrast. T1 relaxation times were quantified for each slice and extracellular volume (ECV) fraction was calculated. The association between the T1 mapping parameters and potential influencing factors were determined using a Pearson correlation. Results: Mean global LV pre-contrast T1 times were 1267.3±39.0ms, post-contrast T1 times were 572.4±53.2ms, ECV were 27.2±2.7%. There were differences of T1 (pre-/post-contrast) times and ECV in different LV level: 1258.8 ms/578.7 ms/26% (base), 1267.8 ms/ 575.6 ms/ 26.5% (mid-ventricle), 1293.5 ms/564.5 ms/29.4% (apex). There were no significant differences of myocardium T1 times between male and females (all P> 0.05), but ECV was slightly higher in women than men (P <0.05). There was negative correlation between global LV ECV fraction and hematocrit (R=-0.65, P<0.01), no correlation between age and T1 mapping parameters were found (all P > 0.05). Conclusion: Myocardial T1 reference values for the specific CMR setting are provided. T1 mapping parameters show no gender and age differences in normal individuals.