Nashat Mohamed, Khedr Lamiaa Abdelghany, Khairat Ebtsam, Elsheikh Eman
Department of Paediatrics, Aswan University, Aswan, Egypt.
Department of Cardiology, Tanta University, Tanta, Egypt.
Ann Pediatr Cardiol. 2021 Oct-Dec;14(4):476-484. doi: 10.4103/apc.apc_162_19. Epub 2022 Mar 25.
Beta-thalassemia major is the most common chronic hemolytic anemia among children and adolescents across the world. Several studies have demonstrated that thalassemic patients who have preserved left ventricle systolic function could still have subtle systolic dysfunction. Among patients with beta-thalassemia, early detection of transfusion-induced myocardial iron loading and its intervention with aggressive chelation therapy may delay or reverse heart failure. Two-dimensional speckle-tracking echocardiography (2D-STE) is a novel tool that may detect early myocardial dysfunction in these patients.
The aim of this study was to investigate whether longitudinal strain based on speckle tracking can detect subtle right or left ventricular dysfunction.
Fifty thalassemic patients with preserved left ventricular ejection fraction (>55%), mean age of 14.75 ± 4.73 years, and thirty age-matched healthy control subjects have been included in the study. Conventional echo Doppler, tissue Doppler echocardiography, and 2D-STE were performed in all patients and control subjects.
The right ventricular and left ventricular longitudinal strains were significantly lower in patients than in controls (21.67 ± 5.59 vs. 25.32 ± 2.29, = 0.001 for right ventricular and 21.29 ± 3.49 vs. 24.90 ± 0.97, = 0.001 for left ventricular).
The 2D-STE can detect early ventricular (left and right) systolic dysfunction in thalassemic patients in the presence of normal systolic function by conventional methods. It may be suggested that the assessment of global longitudinal strain (GLS) can be used as a useful and less expensive tool for screening myocardial iron overload, especially in countries with a limited magnetic resonance imaging (MRI) availability for logistic and economic reasons. Hence, we can refer positive cases with GLS to a higher center to do MRI and start intensive iron chelation treatment.
重型β地中海贫血是全球儿童和青少年中最常见的慢性溶血性贫血。多项研究表明，左心室收缩功能保留的地中海贫血患者仍可能存在细微的收缩功能障碍。在β地中海贫血患者中，早期检测输血诱导的心肌铁负荷并通过积极的螯合疗法进行干预，可能会延缓或逆转心力衰竭。二维斑点追踪超声心动图（2D-STE）是一种可检测这些患者早期心肌功能障碍的新型工具。
本研究旨在调查基于斑点追踪的纵向应变是否能检测出细微的右心室或左心室功能障碍。
本研究纳入了50例左心室射血分数保留（>55%）、平均年龄为14.75±4.73岁的地中海贫血患者以及30例年龄匹配的健康对照者。对所有患者和对照者进行了常规超声多普勒、组织多普勒超声心动图和2D-STE检查。
患者的右心室和左心室纵向应变显著低于对照组（右心室：21.67±5.59对25.32±2.29，P = 0.001；左心室：21.29±3.49对24.90±0.97，P = 0.001）。
2D-STE可以在常规方法检测到收缩功能正常的情况下，检测出地中海贫血患者早期的心室（左心室和右心室）收缩功能障碍。可以认为，整体纵向应变（GLS）评估可作为一种有用且成本较低的工具，用于筛查心肌铁过载，特别是在因后勤和经济原因磁共振成像（MRI）可用性有限的国家。因此，我们可以将GLS阳性的病例转诊至上级中心进行MRI检查并开始强化铁螯合治疗。
