Time Course of Electrocardiographic Changes in Patients with Tako-Tsubo Syndrome - Comparison with Acute Myocardial Infarction with Minimal Enzymatic Release

Background: The time course of the electrocardiographic (ECG) changes in patients with tako-tsubo syndrome remains unknown. Methods and Results: In the present study, 16 patients with tako-tsubo syndrome and 15 patients with anterior acute myocardial infarction with minimal enzymatic release (minimal AMI) were evaluated. Left ventricular dysfunction dramatically resolved approximately 2 weeks later in both groups. In the patients with tako-tsubo syndrome, the admission ECG usually showed ST segment elevation, especially in leads V_3-6. T wave inversion deepened progressively to its first negative peak, which occurred at approximately 3 days. The T wave was shallow for several days and then deepened again, the second negative peak occurring at approximately 2-3 weeks. The QT interval was prolonged as the T wave deepened, and shortened as the T wave became shallow. In the patients with minimal AMI, a similar time course of ECG changes was observed after reperfusion. In general, at 3 days or later during the early phase, T wave inversion was deeper and the QTc interval was longer in tako-tsubo syndrome than in minimal AMI, Conclusions: Because the time course of the ECG changes, as well as that of the left ventricular dysfunction, is similar between tako-tsubo syndrome and minimal AMI, these 2 cardiac disorders must be carefully differentiated.