In-Depth Insight Into the Mechanisms of Cardiac Dysfunction in Patients With Childhood Cancer After Anthracycline Treatment Using Layer-Specific Strain Analysis

Kana Yazaki, Ken Takahashi, Sachie Shigemitsu, Mariko Yamada, Takeshi Iso, Maki Kobayashi, Katsumi Akimoto, Hiroyuki Tamaichi, Junya Fujimura, Masahiro Saito, Masaki Nii, Toshiaki Shimizu

Anthracycline cardiotoxicity affects clinical outcomes, and its early detection using methods that rely on conventional echocardiography, such as left ventricular ejection fraction (LVEF) is difficult. This study aimed to evaluate the characteristics and the differences in cardiac dysfunction among childhood cancer survivors in 3 age groups using layer-specific strain analysis in a wide age range.Methods and Results:The 56 patients (median age: 15 [range: 6.8-40.2] years) who had been treated with anthracycline for childhood cancer were divided into 3 age groups (C1: 6-12 years, C2: 13-19 years, C3: 20-40 years) after anthracycline treatment, and 72 controls of similar ages were divided into 3 corresponding groups (N1, N2, and N3). Layer-specific longitudinal strain (LS) and circumferential strain (CS) of 3 myocardial layers (endocardium, midmyocardium, and epicardium) were determined using echocardiography. Myocardial damage had not occurred yet in C1. Endocardial CS at the basal level was less in C2 than in N2. Endocardial CS at all levels and midmyocardial CS at the basal and papillary levels were lower in C3 than in N3. LVEF and LS were not significantly different between patients and controls. Among survivors of childhood cancer, impaired myocardial deformation starts in adolescence and extends from the endocardium towards the epicardium and from the base towards the apex with age. These findings are a novel insight into the time course of anthracycline cardiotoxicity.