Background: Breast cancer is one of the most prevalent types of cancers among women in Egypt with incidence rates of 48.8 per 100.000 women. Anthracyclines are the drugs of choice for adjuvant chemotherapy in high-risk patients, however, their use is limited due to their cardiotoxicity. In animal models treated with anthracyclines, right ventricle (RV) dysfunction is thought to be an independent prognostic factor and it's possible that it could be an early indicator of subclinical left ventricle (LV) dysfunction. Therefore, further research is required to study the cardiotoxic effect of anthracycline drugs on the RV using different 2D echocardiographic modalities. Subjects and Methods: A total number of 40 newly diagnosed breast cancer patients who were planned to receive doxorubicin therapy for 37 of them and epirubicin for 3 patients were prospectively recruited. Serial 2 D echocardiograms including speckle-tracking were done at baseline, 3 months later, and 6 months later. Results: RV dysfunction was detected more byright ventricle global longitudinal strain (RVGLS) after six months of anthracycline-based chemotherapy (-22.85±1.31 vs. -19.30±2.30, P value 0.001). ROC curve revealed a total anthracycline cumulative dose of 416 mg/m² with the highest sensitivity and specificity of RV dysfunction. Conclusion: RVGLS surpassed other traditional 2D metrics in identifying subclinical RV disease, and the total anthracycline cumulative dose is strongly linked to the incidence of chemotherapy related cardiotoxicity to the right ventricle. 2D speckle-tracking is noninvasive and feasible modality that can be used to detect early anthracycline-induced cardiotoxicity.