QT interval prolongation during ECG evolution in takotsubo cardiomyopathy poses a threat of torsade de pointes to predisposed patients

We report the case of a female patient with congenital complete atrioventricular block who developed torsade de pointes (TdP) in the course of takotsubo cardiomyopathy. On the basis of this case, we show that the electrocardiographic evolutionary changes with QT interval prolongation (in the course of takotsubo cardiomyopathy) may be a TdP threatening period in patients with underlying predispositions. After reviewing the literature, we also present the electrocardiographic similarities between takotsubo cardiomyopathy and other acute heart diseases associated with a large amount of stunned myocardium, i.e., other stress-related cardiomyopathies (e.g., those associated with subarachnoid hemorrhage, pheochromocytoma, or severe illnesses) as well as a reperfused myocardial infarction. QT interval prolongation is a common feature in the subacute phase of these entities; however, excessive QT prolongation may be a sign of predisposition to TdP. In such instances, measures should be taken to monitor cardiac rhythm closely and to prevent or treat TdP appropriately. Taking into account the risk of TdP, it is reasonable to consider takotsubo cardiomyopathy as a potential cause of acquired long QT syndrome.