CMR image analysis:
The acquired CMR images were independently analyzed by two cardiac
radiologists with 12 and 10 years of MRI diagnosis experience.
Discrepancies in the analysis of the two radiologists were adjudicated
by a senior radiologist having 20 years of experience in MRI diagnosis.
The CMR images were post processed and cardiac chamber volumes, mass and
function were measured using software based automated cardiac contour
detection along with manual correction if required. All the image
sequences were analyzed as per the 16-segment model proposed by the
American Heart Association.13 The location as well as
the pattern (epicardial, mid-wall, or transmural) of LGE were assessed
independently by two observers. The global T1/T2 values were computed by
manually delineating the entire LV myocardium on the T1/T2 map.
Myocarditis was diagnosed based on the 2018 revised Lake Louis criteria
(LLC)14 in the presence of both of the main criteria:
(1) myocardial edema (T2 mapping or T2 darkblood TIRM-Sequences) and (2)
non-ischemic myocardial injury (abnormal T1, ECV or LGE).