Unlike other cancer therapy-related cardiac dysfunction (CTRCD), HER2-targeted therapy-related cardiotoxicity is generally reversible on treatment discontinuation,15, 17 and late cardiotoxicity is uncommon.15 18 For patients with early breast cancer, the duration of HER2-targeted therapy is 12 months and normalisation of cardiac function occurs in most patients; over 80% of patients with breast cancer and HER2 CTRCD show recovery at a median of 7 months post initial dysfunction.15 This evidence concerns the gene ERBB2 and breast cancer.