Takotsubo cardiomyopathy caused by infusion reaction to trastuzumab

Takotsubo cardiomyopathy (TCM) is also known as stress-induced cardiomyopathy. The occurrence of TCM due to infusion reaction is extremely rare. A 65-year-old man began receiving trastuzumab monotherapy for gastric cancer. However, he developed an infusion reaction after administration. Electrocardiography revealed negative T waves, ST segment elevation, and apical akinesis and hypokinesis of the left ventricle with apical ballooning in the systole and diastole. Furthermore, troponin I and creatinine kinase (CK) levels and CK-myocardial band were elevated. Based on these findings, he was diagnosed with TCM. This is the first report of TCM due to an infusion reaction.