Introduction: To date in thalassemia patients it is recommended to repeat cardiac magnetic resonance (CMR) scans for iron quantification every 1 or 2 years based on the myocardial iron overload (MIO). Also in these patients, late gadolinium enhancement (LGE) has been demonstrated to be a strong predictor for cardiac events. However, many studies have shown an association between intravenous gadolinium based contrast agents (GBCA) exposure and neuronal tissue deposition. So, it appears prudent at this time to revisit institutional protocols for GBCA administration, in particular in the follow up (FU) studies.

Aim: We investigated the evolution of myocardial fibrosis in terms of new occurrences over a period of 6 years in thalassemia patients who underwent to multiple FU.

Methods: We considered 52 patients with thalassemia major (28.78±8.59 years; 28 females) consecutively enrolled in the Myocardial Iron Overload in Thalassemia (MIOT) Network who underwent 5 LGE CMRs (baseline + 4 follow-up) using Gadobutrol (0.2 mmoli/kg). The time interval between two subsequent scans was 18±3 months.

Results: At the baseline CMR, 44 patients (84.6%) were LGE-negative.

Eight new occurrences of myocardial fibrosis were detected at the first follow-up (FU). At the second FU, 2 out of the 36 previously LGE-negative patients had myocardial fibrosis. At the third FU, 9 new occurrences of myocardial fibrosis were detected. At the forth FU, 3 patients showed myocardial fibrosis for the first time. The figure shows a simplifying flow-chart.

The 22 patients who developed myocardial fibrosis during the follow-up showed comparable frequency of diabetes and HCV infection and comparable baseline cardiac iron than patients who remained always LGE-negative.

Conclusion: A serial monitoring of thalassemia patients revealed an high number of new occurrences of myocardial fibrosis, suggesting the importance of repeating the LGE CMR over time using 'low risk' macrocyclic agents.