Cardiac MRI for detecting acute myocardial injury of fulminant myocarditis survivors after ECMO treatment in adults

Introduction To detect the acute myocardial injury in fulminant myocarditis (FM) survivors after ECMO and to demonstrate its significant differences from non-FM patients by cardiac MR (CMR). Materials and Methods This retrospective study enrolled 59 patients with acute myocarditis (AM), including 35 non-FM patients and 24 FM patients, and 54 controls. Peak value of cardiac troponin T (cTnT) was recorded. Tissue parameters including native T1, ECV, LGE%, and T2 by CMR were assessed. Results Mean age was 35±14 years and 45.8% of population were males in AM group. Patients had higher levels of peak cTnT, peak NT-proBNP and peak CRP in FM group (all p<0.05). Comparing with non-FM, the values of T1-based imaging parameters were significantly higher in FM group (all p<0.05). In contrast, no difference was observed among the two groups in terms of T2 value (p=0.707). The septal area was more frequently involved in FM survivors after ECMO treatment both in T1 and T2-based images. In addition, cubic relationship was relative best fit of LGE% against logcTnT and indicated that cTnT value exceeding 300ng/L exhibited a rapid upward trend of LGE%. Conclusions Comparing to non-FM, higher myocardial necrosis and fibrosis but similar edema determined by T1 and T2 based imaging was found in FM survivors after ECMO treatment. Furthermore, the inter-ventricular septal area was more frequently involved by acute myocardial injury in FM survivors after ECMO treatment. In addition, LGE% showed an overall increasing trend with cTnT values elevating with rapidly increasing with cTnT exceeding 300 ng/L.