An 81-year-old woman was admitted with chest pain. An electrocardiogram demonstrated ST segment elevation in leads II, III and aVF, and echocardiography revealed left ventricular apical asynergy with a left-to-right ventricular shunt. Meanwhile, emergent coronary angiography showed no significant coronary artery stenosis, whereas left ventriculography indicated apical ballooning and a left-to-right ventricular shunt. We therefore diagnosed the patient with Takotsubo cardiomyopathy complicated by ventricular septal perforation and cardiogenic shock. An electrocardiogram disclosed a prolonged QT interval over time, and the patient became hemodynamically stable under treatment with inotropes; however, she suddenly developed fatal ventricular fibrillation three days after hospitalization. Takotsubo cardiomyopathy complicated by ventricular septal perforation is a critical condition that requires careful monitoring.