OBJECTIVES: This study sought to test the diagnostic performance of native T1 
mapping in acute myocarditis compared with cardiac magnetic resonance (CMR) 
techniques such as dark-blood T2-weighted (T2W)-CMR, bright-blood T2W-CMR, and 
late gadolinium enhancement (LGE) imaging.
BACKGROUND: The diagnosis of acute myocarditis on CMR often requires multiple 
techniques, including T2W, early gadolinium enhancement, and LGE imaging. Novel 
techniques such as T1 mapping and bright-blood T2W-CMR are also sensitive to 
changes in free water content. We hypothesized that these techniques can serve 
as new and potentially superior diagnostic criteria for myocarditis.
METHODS: We investigated 50 patients with suspected acute myocarditis (age 42 ± 
16 years; 22% women) and 45 controls (age 42 ± 14 years; 22% women). CMR at 
1.5-T (median 3 days from presentation) included: 1) dark-blood T2W-CMR 
(short-tau inversion recovery); 2) bright-blood T2W-CMR (acquisition for cardiac 
unified T2 edema); 3) native T1 mapping (shortened modified look-locker 
inversion recovery); and 4) LGE. Image analysis included: 1) global T2 signal 
intensity ratio of myocardium compared with skeletal muscle; 2) myocardial T1 
relaxation times; and 3) areas of LGE.
RESULTS: Compared with controls, patients had significantly higher global T2 
signal intensity ratios by dark-blood T2W-CMR (1.73 ± 0.27 vs. 1.56 ± 0.15, p < 
0.01), bright-blood T2W-CMR (2.02 ± 0.33 vs. 1.84 ± 0.17, p < 0.01), and mean 
myocardial T1 (1,010 ± 65 ms vs. 941 ± 18 ms, p < 0.01). Receiver-operating 
characteristic analysis showed clear differences in diagnostic performance. The 
areas under the curve for each method were: T1 mapping (0.95), LGE (0.96), 
dark-blood T2 (0.78), and bright-blood T2 (0.76). A T1 cutoff of 990 ms had a 
sensitivity, specificity, and diagnostic accuracy of 90%, 91%, and 91%, 
respectively.
CONCLUSIONS: Native T1 mapping as a novel criterion for the detection of acute 
myocarditis showed excellent and superior diagnostic performance compared with 
T2W-CMR. It also has a higher sensitivity compared with T2W and LGE techniques, 
which may be especially useful in detecting subtle focal disease and when 
gadolinium contrast imaging is not feasible.