Diagnostic Accuracy of Mapping Techniques and Postprocessing Methods for Acute Myocarditis.

ABSTRACT

OBJECTIVE. Many T1 mapping sequences and measurement methods have been reported in the literature. To obtain accurate results, the most appropriate T1 and T2 mapping sequences and postprocessing methods should be used. The aim of the present study is to compare the T1 and T2 mapping sequences and measurement methods used to diagnose acute myocarditis. MATERIALS AND METHODS. Fourteen patients with an interval of 7 days or less between symptom onset and MRI examination were included in the study. The control group consisted of 22 healthy individuals. T1 mapping images acquired using four different methods (modified Look-Locker inversion recovery [MOLLI] 3[3]3[3]5, MOLLI 3[2]3[2]5, MOLLI 5[3]3 heart rate-corrected, and MOLLI 5[3]3 heart rate-uncorrected sequences) and T2 mapping images obtained using two different methods (FLASH and true fast imaging with steady-state precession) in the area from the short axis through the basal slice were retrospectively evaluated. RESULTS. The mean T1 and T2 values were significantly higher in the patient group than in the control group for all sequences in SAX measurements and segmental measurements (segments 1, 4, 5, and 6). Measurements from segments 2 and 3 were not statistically significant between patient and control groups. The segment with the highest AUC value of T1 and T2 mapping values was the inferior segment, followed by the inferolateral segment. The highest diagnostic performance for short-axis measurements was obtained using the MOLLI 3(2)3(2)5 sequence (AUC value = 0.902). CONCLUSION. According to the results of this study and many other studies, pathologic changes in the myocardium can be detected by native T1 and T2 mapping. The accuracy of mapping methods will increase with increased knowledge of the advantages and disadvantages of currently used sequences and measurement methods.