Evaluation of Different Arrhythmias and Cardiac Iron Overload Status in β-Thalassemia Major: A Cross-Sectional Study

Cardiac involvement due to iron deposition in β-thalassemia major remains the main cause of mortality. We assessed the effects of cardiac iron overload on the incidence of arrhythmias in β-thalassemia major.

The present cross-sectional study enrolled patients with β-thalassemia major referred to a tertiary cardiovascular care center in Tehran, Iran, between January 2019 and January 2020. The patients’ characteristics were collected using hospital records. Cardiac iron overload status was assessed using cardiac T2* magnetic resonance (severe ≤10 ms, moderate =10–20 ms, and mild =20 ms).

The present study recruited 81 β-thalassemia major cases with a mean age (SD) of 30.69 (11.12) years. Mild, moderate, and severe iron overload statuses were reported in 44.4%, 22.2%, and 33.3% of the stud population, respectively. Of 44 patients (54.3%) with arrhythmias, supraventricular tachyarrhythmias were seen in 24.7%, ventricular tachycardias in 19.8%, and atrioventricular blocks in 9.9%. A significant association was reported between iron overload status and the presence of arrhythmias (P<0.001). There was a significant association between iron overload and dilated atria (P=0.004). The left ventricular ejection fraction (LVEF) was not associated with cardiac iron status, but it was associated with the presence of arrhythmias (P<0.001). Desferal therapy was considerably associated with cardiac iron status (P=0.04).

According to iron chelation therapy, patients with more severe iron overload had a higher incidence rate of arrhythmias. Additionally, patients with lower LVEF values had a higher incidence rate of arrhythmias. There was no statistically significant association between LVEF and cardiac iron overload status. (Iranian Heart Journal 2022; 23(4): 60-68)