Improvement of heart iron with preserved patterns of iron store by CMR-guided chelation therapy

AIMS: [Formula: see text] multislice multiecho cardiac magnetic resonance (CMR) allows quantification of the segmental distribution of myocardial iron overload (MIO). We evaluated whether a preferential pattern MIO was preserved between two CMR scans in regularly chelated thalassaemia major (TM) patients. METHODS AND RESULTS: We evaluated prospectively 259 TM patients enrolled in the MIO in Thalassaemia (MIOT) network with a CMR follow-up (FU) study at 18 ± 3 months and significant MIO at baseline. The [Formula: see text] in the 16 segments and the global value were calculated. Four main circumferential regions (anterior, septal, inferior and lateral) were defined. We identified two groups: severe (n = 80, global [Formula: see text] <10 ms) and mild-moderate MIO (n = 179, global [Formula: see text] = 10-26 ms). Based on the CMR reports, 56.4% of patients changed the chelation regimen. For each group, there was a significant improvement in the global heart as well as in regional [Formula: see text] values (P < 0.0001). At the baseline, the mean [Formula: see text] value over the anterior region was significantly lower than the values over the other regions, and the mean [Formula: see text] over the inferior region was significantly lower than the values over the septal and the lateral regions. The same pattern was present at the FU, with a little difference for patients with mild-moderate MIO. CONCLUSION: A preferential pattern of iron store in anterior and inferior regions was present at both CMRs, with an increment of [Formula: see text] values at FU due to a baseline CMR-guided chelation therapy. The anterior region seems the region in which the iron accumulates first and is removed later.