Early Detection of Subclinical Left Ventricular Dysfunction in Transfusion-Dependent Thalassemia Using Global Longitudinal Strain and Myocardial Work Indices

Abstract

Objectives: This study aimed to detect early, pre-symptomatic cardiac involvement in transfusion-dependent thalassemia (TDT) patients using Speckle-Tracking Echocardiography (STE) and Global Longitudinal Strain (GLS), in order to facilitate timely initiation or adjustment of chelation therapy and prevent progression to overt cardiomyopathy. The additional diagnostic value of myocardial work indices was also explored. Methodology: In this cross-sectional study, 100 adult TDT patients underwent STE to assess GLS and myocardial work parameters. Serum ferritin levels were measured as a biomarker of iron overload and potential cardiac dysfunction. Participants were stratified into two groups based on GLS: normal GLS (> –18) and left ventricular (LV) dysfunction (GLS ≤ –18). Results: Among the 100 participants (mean age: 26 ± 6 years; 52% male), subclinical LV dysfunction was identified in 43%. The LV dysfunction group demonstrated significantly elevated serum ferritin levels (5023 ± 1848 vs. 3026 ± 690 ng/ml, p < 0.001), reduced LVEF (61.75 ± 4.17% vs. 67.99 ± 4.73%, p < 0.001), and impaired GLS (–17.8 ± 1.0% vs. –20.8 ± 1.3%, p < 0.001). Serum ferritin showed strong diagnostic performance for LV dysfunction (AUC: 0.844), with a sensitivity of 83.3% and specificity of 68.4% at a cutoff value of 3185.5 ng/ml. On multivariate logistic regression, elevated serum ferritin (OR: 1.002, p = 0.010) and lack of chelation therapy (OR: 0.014, p = 0.005) emerged as significant predictors of LV dysfunction. Conclusion: STE-derived GLS is a sensitive tool for detecting subclinical LV dysfunction in TDT patients. Elevated serum ferritin levels may serve as a useful surrogate marker for early myocardial involvement, underscoring the importance of regular monitoring and optimization of chelation therapy to avert cardiac complications.