Diagnostic Modalities in Detecting Cardiovascular Complications of Thalassemia

Abstract

Thalassemia major is the most common monogenetic disorder worldwide, manifested as chronic hemolytic anemia. This condition leads to the need for chronic blood transfusion to be monitored for an iron overload that may be stored in several tissues and organs, including cardiomyocytes, that might cause a broad spectrum of cardiac iron toxicities such as heart failure conduction delays, myocarditis, and arrhythmias. Non-invasive imaging modalities have their benefits and limitations. Each modality complements and generates a comprehensive diagnostic and monitoring of cardiac siderosis in thalassemia major patients.

Keywords: cardiac siderosis; diagnostic modalities; thalassemia major.

Fig. 1.

Pathomechanism of cardiac iron toxicity in TDT patients. Chronically transfused TDT patients gain 5.8–11.6 grams of iron annually. Labile iron is stored as non-transferrin bound iron (NTBI) in siderosomes, creating an iron-ferritin complex that may be stable for years. On the other hand, NTBI interacts with cardiomyocytes creating impairments that lead to cardiomyopathy and events of arrhythmias, causing the heart to be the most targeted organ in thalassemia. Na, sodium; K, potassium; HbF, Hemoglobin F; 2,3 BPG, 2,3 biphosphoglycerate.