Myocardial T1 and T2 mapping at 3 T: reference values, influencing factors and implications

Abstract

BackgroundMyocardial T1 and T2 mapping using cardiovascular magnetic resonance (CMR) are promising to improve tissue characterization and early disease detection. This study aimed at analyzing the feasibility of T1 and T2 mapping at 3 T and providing reference values.MethodsSixty healthy volunteers (30 males/females, each 20 from 20–39 years, 40–59 years, 60–80 years) underwent left-ventricular T1 and T2 mapping in 3 short-axis slices at 3 T. For T2 mapping, 3 single-shot steady-state free precession (SSFP) images with different T2 preparation times were acquired. For T1 mapping, modified Look-Locker inversion recovery technique with 11 single shot SSFP images was used before and after injection of gadolinium contrast. T1 and T2 relaxation times were quantified for each slice and each myocardial segment.ResultsMean T2 and T1 (pre-/post-contrast) times were: 44.1 ms/1157.1 ms/427.3 ms (base), 45.1 ms/1158.7 ms/411.2 ms (middle), 46.9 ms/1180.6 ms/399.7 ms (apex). T2 and pre-contrast T1 increased from base to apex, post-contrast T1 decreased. Relevant inter-subject variability was apparent (scatter factor 1.08/1.05/1.11 for T2/pre-contrast T1/post-contrast T1). T2 and post-contrast T1 were influenced by heart rate (p < 0.0001, p = 0.0020), pre-contrast T1 by age (p < 0.0001). Inter- and intra-observer agreement of T2 (r = 0.95; r = 0.95) and T1 (r = 0.91; r = 0.93) were high. T2 maps: 97.7% of all segments were diagnostic and 2.3% were excluded (susceptibility artifact). T1 maps (pre-/post-contrast): 91.6%/93.9% were diagnostic, 8.4%/6.1% were excluded (predominantly susceptibility artifact 7.7%/3.2%).ConclusionsMyocardial T2 and T1 reference values for the specific CMR setting are provided. The diagnostic impact of the high inter-subject variability of T2 and T1 relaxation times requires further investigation.

HIV-1–Related Cardiovascular Disease Is Associated With Chronic Inflammation, Frequent Pericardial Effusions, and Probable Myocardial Edema

“…First, native myocardial T1 values may increase with myocardial edema, fibrosis, infarction, myocarditis, or amyloidosis and are not specific for myocardial inflammation or fibrosis as discussed. Second, T2 mapping was not performed, which would have been an interesting comparison; however, T2 mapping at the present time seems to have a large interindividual variability, 43 which may not have helped significantly in distinguishing between myocardial water from inflammation and that in an expanded extracellular space. Third, postcontrast T1 mapping and extracellular volume quantification were not performed.…”

Cardiac Involvement in Myotonic Dystrophy Type 2 Patients With Preserved Ejection Fraction

“…27 Both the values of T2 and T1 maps were quantified as previously reported. 28 The qualitative survey implied the exclusion of segments in case of artifacts (eg, caused by susceptibility effects or unintended thoracic motion) or wrong motion correction as described recently. 28 We performed inter-and intraobserver variability analysis.…”

T1 Mapping in Characterizing Myocardial Disease

“…The results of studies reporting these in various sequences are summarized in Table 2. The true effects of age and sex remain unclear because studies reported discordant associations: T1 values were shown to decrease, 37 increase, 38,39 or have no relationship with age. 26 Similarly, in some studies, females were shown to have higher T1 values, 37,38 whereas others showed no relationship with sex.…”