PURPOSE: The objective of this study is to compare the diagnostic utility of a novel fat water phase sensitive inversion recovery (PSIR) late gadolinium enhancement CMR sequence to standard bright blood PSIR LGE in patients with suspected myocarditis.
METHODS: Twenty-eight patients referred for clinical CMR were scanned. A full left ventricle short axis stack was performed using both techniques. Two experienced observers analyzed all bright blood LGE and FW PSIR LGE stacks. A scoring system was devised to quantify the presence and extent of gadolinium enhancement.
RESULTS: All patients presented with chest pain, a raised troponin (Troponin T median 583ng/L, interquartile range 98-1247ng/L) and a normal coronary angiogram or very low probability of coronary artery disease. A total of 448 LV segments were analysed. FW PSIR LGE analysis found 140% more segments that exhibited subepicardial enhancement in comparison to bright blood LGE (116/448 FW PSIR LGE positive segments vs 45/448 BB LGE positive segments; p < 0.05). FW LGE also allowed observers to be more confident when diagnosing LGE (p<0.05). Nine patients (32%) with no bright blood LGE (who were therefore classified as normal on bright blood LGE) were found to have subepicardial LGE on FW PSIR LGE.
CONCLUSIONS: FW PSIR LGE significantly increases subepicardial LGE detection in patients with suspected myocarditis compared to standard bright blood LGE and changes the diagnosis in 32% of patients, which has important clinical implications.