Comparative Diagnostic Value of 3D Volumetry and Speckle-Tracking over Conventional 2D Echocardiography in the Evaluation of Left Ventricular Function in Pediatric Transfusion-Dependent Beta-Thalassemia

Background: Left ventricular (LV) dysfunction remains the leading cause of mortality in transfusion-dependent beta-thalassemia (TDßT), yet conventional echocardiography often fails to detect early myocardial impairment. This study aimed to comprehensively evaluate LV function in children with TDßT using three-dimensional echocardiography (3DE) and speckle-tracking strain analysis, comparing diagnostic performance with conventional two-dimensional (2D) parameters. Results: 50 TDßT patients were compared to 50 matched controls and exhibited preserved conventional LV ejection fraction (EF) on 2D (65.31 ± 7.12% vs. 69.21 ± 3.87%, p = 0.001), but 3DE revealed significant ventricular dilation with higher end-diastolic volume index (75.50 ± 17.99 vs. 65.63 ± 11.86 mL/m2, p = 0.002) and end-systolic volume index (22.28 ± 7.85 vs. 18.21 ± 5.14 mL/m2, p = 0.003). Despite preserved 3D EF (70.79 ± 5.98% vs. 72.07 ± 5.76%, p = 0.276), global longitudinal strain (GLS) was significantly impaired (−18.56 ± 2.37% vs. −21.47 ± 1.86%, p < 0.001). 3D volumetric parameters demonstrated superior diagnostic performance (AUC for LVEDVI Z-score = 0.874) compared to conventional indices. Transfusion duration correlated strongly with ventricular volumes (r = 0.569 for EDV, p < 0.001), while serum ferritin showed no significant correlation with cardiac parameters. Conclusions: Children with TDßT develop early subclinical LV dysfunction detectable by 3DE and strain analysis despite preserved conventional systolic indices. 3D volumetry and GLS should be integrated into routine cardiac surveillance protocols to enable timely therapeutic intervention.