Table 1 Information provided by various CMR techniques applied in the evaluation of acute myocarditis, with main imaging features
From: Lights and shadows of cardiac magnetic resonance imaging in acute myocarditis
CMR technique | Information provided | Imaging features |
|---|---|---|
Cine-SSFP | Regional and global biventricular function, ventricular mass, and parietal wall thickness | - Normal or mildly dilated left or biventricular cavities |
- Ejection fraction depending on clinical presentation, usually mildly depressed (45–50 %) | ||
- Parietal wall thickness normal or slightly increased (>10Â mm) | ||
- Pericardial effusion in 30–50 % of cases | ||
T2w-STIR | Increased myocardial free water content | - Subepicardial or patchy areas of high signal intensity following LGE distribution |
- Global hyperintensity compared to skeletal muscle (T2 ratio > 1.9 according to LLc) | ||
Pre- and post-Gd T1w FSE | Myocardial hyperemia and expansion of extracellular compartment | - Sequences frequently affected by severe artefacts |
- Myocardial hyper-enhancement compared to skeletal muscle (EGEr > 4 according to LLc) | ||
Delayed enhancement | Myocardial necrosis, scars | - No enhancement |
- Focal subepicardial enhancement typically involving inferolateral LV wall | ||
- Patchy or longitudinal striae of mid-wall enhancement | ||
Native T1 mapping | Pixel-by-pixel assessment of T1-rt revealing myocardial changes, first of all oedema | - T1-rt prolongation: proposed cut-off > 990 ms (59) |
Pre- and post-Gd T1 mapping | ECV expansion due to enhanced diffusion of free water and cardiomyocyte apoptosis | - ECV increase: proposed cut-off ≥ 27 %; still few published data (34) |
T2 mapping | Pixel-by-pixel assessment of T2-rt revealing myocardial oedema | - T2-rt prolongation; still few published data (64) |