The overexpression of human epidermal growth factor receptor-2 (HER2) in breast cancer is a poor prognosis. Trastuzumab improves overall survival but is associated with cardiotoxicity, especially a decline in left ventricular ejection fraction (LVEF). | A phase 2 randomized trial to evaluate the impact of a supervised exercise program on cardiotoxicity at 3 months in patients with HER2 overexpressing breast cancer undergoing adjuvant treatment by trastuzumab Design of the CARDAPAC study