Children with acute lymphoblastic leukemia (ALL) are treated with doxorubicin-based chemotherapy that can lead to cardiotoxicity which is a well-known cause of mortality. This study aims to characterize myocardial subtle changes induced by doxorubicin-related cardiotoxicity. We used the combination of cardiac magnetic resonance (CMR) imaging, cardiopulmonary exercise testing and the CircAdapt model to explore hemodynamics and intraventricular mechanisms at rest and during exercise in 53 childhood ALL survivors. A sensitivity analysis of the CircAdapt model identified the most influencing parameters on the left ventricle volume. ANOVA were performed to explore significant differences between left ventricle stiffness, contractility, and arteriovenous pressure drop, as well as survivors’ prognostic risk groups. No significant differences were observed between prognostic risk groups. The left ventricle stiffness and left ventricle contractility were non-significantly higher in survivors receiving cardioprotective agents (94.3 %), compared to those at standard and high prognostic risk (77 % and 86 %, respectively). In both left ventricle stiffness and left ventricle contractility, we observed that survivors receiving cardioprotective agents were close to the nominal value of CircAdapt (healthy reference group value is 100 %). This study allowed to improve our knowledge of potential subtle myocardial changes induced by doxorubicin-related cardiotoxicity in childhood ALL survivors. This study confirms that survivors exposed to a high cumulative dose of doxorubicin during treatments are at potential risk of myocardial changes many years after the end of their cancer, while cardio-protective agents may prevent changes in cardiac mechanical properties.