Repolarization Abnormalities in Patients With Takotsubo Syndrome Versus Acute Anterior Myocardial Infarction

Takotsubo syndrome (TTS) is characterized by ST-segment deviations and T-wave inversions in electrocardiogram (ECG) recordings, accompanied by an increased risk of ventricular arrhythmias. This study aimed to investigate the repolarization abnormalities of ECG parameters in TTS patients by comparing them with those of acute anterior myocardial infarction (AMI).

A total of 168 patients diagnosed with TTS, AMI of the anterior wall, and matched controls who underwent coronary angiogram were enrolled from 962 consecutive admissions. ECG repolarization parameters were measured and analyzed.

After matching, there were no significant differences in baseline characteristics among the TTS (n = 24), AMI (n = 72), and matched control (n = 72) groups (p > 0.05). Compared with matched controls, both the TTS and AMI groups had significantly increased QTc (p < 0.001), QT dispersion (p < 0.001), and T_p-e dispersion (p < 0.001). However, in the subacute phase, TTS patients exhibited significantly more severe repolarization abnormalities compared with those with anterior wall AMI, including increased T_p-e (p < 0.001), T_p-e dispersion (p = 0.002), and T_p-e/QTc ratio (p < 0.001). ECG indicators showed that the areas under the receiver operating characteristic (ROC) curves for differentiating TTS from AMI using T_p-e/QTc ratio, T_p-e, and T_p-e dispersion were 0.78, 0.74, and 0.71, respectively. Furthermore, T_p-e dispersion and QT dispersion were also associated with ventricular arrhythmias in patients with TTS and AMI, respectively, indicating that these ECG parameters are valuable for identifying TTS and predicting arrhythmias.

TTS is associated with increased QT dispersion, T_p-e, T_p-e dispersion, and T_p-e/QTc ratio when compared with anterior wall AMI and matched controls. These distinct repolarization abnormalities may be related to the occurrence of ventricular arrhythmias.