Study on the Dosage of Anthracycline Drugs and Its Effect on Left Atrial and Ventricular Strain in Children with Leukemia: Based on Cardiac Magnetic Resonance Feature Tracking Technology (RF_TH_246)

Anthracycline drugs are conventional chemotherapeutic agents used in children with leukemia. According to 2022 ESC Guidelines on cardio-oncology, a cumulative doxorubicin dosage of less than 100 mg/m2 is considered low risk for cardiac complications, while others are deemed high risk. Atrial and ventricular strain detected by cardiac magnetic resonance imaging (MRI) technology can facilitate early detection of cardiac functional damage caused by cardiotoxic agents. However, the impact of cumulative anthracycline dosage on early cardiac dysfunction in Chinese children with leukemia remains incompletely understood. This study aims to investigate the effects of cumulative anthracycline dosage on early cardiac dysfunction in children with leukemia.

Methods:

In this retrospective study, pediatric leukemia patients from a single-center cohort during 2016 to 2020 were recruited. Additionally, a comparable group of age-matched healthy children served as controls. The population was stratified into three groups: normal, low-dose anthracycline (< 100 mg/m²), and high-dose anthracycline (≥100 mg/m²). Standard magnetic resonance parameters were evaluated, alongside atrial and ventricular strain, which were quantified as global longitudinal strain (LVGLS), global radial strain (LVGRS), global circumferential strain (LVGCS), reservoir strain (Ɛs), conduit strain (Ɛe), and contraction strain (Ɛa). Spearman's correlation analysis was performed within each group to assess the relationship between left atrial and left ventricular stresses. For statistical analysis, all strain values were converted to absolute magnitudes.

Results:

A total of 109 children with leukemia and 48 healthy children were enrolled in the study. The correlation between left ventricular strain and left atrial strain in children with leukemia was generally lower than that in normal children, especially for the relationship between LVGLS and Ɛa (r=0.01 vs r=0.39). That correlation in the group with an anthracycline cumulative dosage of < 100 mg/m² was generally lower than that in the group with an anthracycline cumulative dosage of ≥100 mg/m², particularly for the relationship between LVGCS and Ɛs (r=0.004 vs r=0.34). The Ɛa in the group with an anthracycline dosage of < 100 mg/m² was significantly higher than that in the normal group: p=0.008, 25 (20, 30) vs 20 (16, 25). The left atrial active ejection fraction in the group with an anthracycline dosage of < 100 mg/m² was significantly higher than that in the group with an anthracycline dosage of ≥100 mg/m²: p=0.034, 48 ± 14 vs 39 ± 16.

Conclusion:

In pediatric leukemia patients, subtle cardiac functional impairments have been observed, which are correlated with the dosage of anthracycline medications. Notably, these impairments manifest asynchronously in the left atrium and left ventricle, a phenomenon that may be attributed to the compensatory mechanisms inherent in the left atrium. 

Figure 1 | Spearman correlation between left atrial strain and left ventricular strain in different groups.