Significance Understanding the initiating mechanisms of cardiac injury associated with doxorubicin is fundamental to the development of novel preventative strategies. Evidence suggests that expression of membrane transporters contributes to the initial accumulation of doxorubicin in cardiomyocytes and, subsequently, cellular injury. Using patient-derived cardiomyocytes, we identified a candidate membrane transporter contributing to this debilitating phenotype and performed validation studies using engineered cell-based and animal models to demonstrate that targeting this transport mechanism can afford cardio-protection without compromising the anticancer properties of doxorubicin. Our findings provide insights that addresses an unmet therapeutic need in cancer patients receiving doxorubicin-based treatment.