Detection of Subclinical Anthracyclines' Cardiotoxicity in Children with Solid Tumor

Background: Cardiotoxicity is one of the most serious chronic complications of anthracyclines therapy. Assessment of the left ventricular ejection fraction (LVEF) fails to detect subtle cardiac dysfunction of left ventricular (LV). This study aimed to detect and evaluate new parameters of subclinical anthracyclines' cardiotoxicity in children with solid tumor. Methods: A detailed echocardiographic examination was performed in 36 children with hepatoblastoma or rhabdomyosarcoma after receiving anthracyclines' chemotherapy and 36 healthy controls from January 2015 to December 2016. The LVEF, ratio of early diastolic peak velocity of transmitral flow (E) and septal diastolic e' mitral annular peak velocity (e'), tricuspid annular plane systolic excursion (TAPSE), and LV global longitudinal strain (GLS) were evaluated using M-mode, tissue Doppler imaging (TDI), and two-dimensional speckle tracking echocardiography (2D-STE), respectively. Echocardiographic parameters were compared between patient group and healthy controls. All patients were divided into two subgroups based on their anthracyclines' cumulative dosage (<300 mg/m2 subgroup and ≥300 mg/m2 subgroup). Results: All patients had no presentation of heart failure and LVEF within normal range (65.7 ± 5.1%). Compared with healthy controls, the mean E/e' increased significantly (7.9 ± 0.7 vs. 10.2 ± 3.5, t = 3.72, P < 0.01), mean TAPSE decreased significantly (17.2 ± 1.3 mm vs. 14.2 ± 3.0 mm, t = −4.03, P < 0.01), and mean LV GLS decreased significantly (−22.2% ± 1.9% vs. −17.9% ± 2.9%, t = -5.58, P < 0.01) in patient group. Compared with subgroup with anthracyclines' cumulative dosage < 300 mg/m2, mean LV GLS decreased significantly (−18.7 ± 2.7% vs. −16.5 ± 2.1%, t = 2.15, P = 0.04), the mean E/e' increased significantly (9.1 ± 1.5 vs. 11.5 ± 4.9, t = −2.17, P = 0.04), and mean TAPSE decreased significantly (14.2 ± 2.1 mm vs. 12.5 ± 2.2 mm, t = −2.82, P = 0.02) in subgroup with anthracyclines' cumulative dosage ≥300 mg/m2. Conclusions: LV GLS is helpful in the early detection of subclinical LV dysfunction using 2D-STE. E/e' and TAPSE are other sensitive parameters in detecting subclinical cardiac dysfunction of both ventricles by TDI. These parameters show significant change with different anthracyclines' cumulative dosage, so cumulative dosage should be controlled in clinical treatment