Plausible mechanisms of the rapid conversion of ST-segment elevation to T-wave inversion in Takotsubo syndrome.

Takotsubo syndrome (TTS) is characterized by electrocardiogram (ECG) diffuse ST-segment elevations (+ST), and T-wave inversions with prolongation of the QTc interval. Thus ECG-wise, TTS is not different from acute coronary syndromes (ACSs). However unlike acute ST-elevation myocardial infarction, one type of ACS, a rapid conversion of+ST to T-wave inversion with prolongation of the QTc interval is seen in TTS. The author hypothesizes that this conversion is paralleled by a change of segmental myocardial dyskinesis to akinesis, development of myocardial edema, and reversion of the cardioinhibitory ß-2 adrenergic receptor function, to its cardiostimulatory normal status. This hypothesis does not negate the plausibility that the ECG changes in TTS are due to myocardial ischemia/injury as traditionally perceived in ACSs. The reasons of the counterintuitive concurrence of the cardiac contractility to normal, or previous baseline status, while myocardial edema and T-wave inversions persist for several weeks in patients with TTS, are still elusive.