Differences in negative T waves between takotsubo cardiomyopathy and reperfused anterior acute myocardial infarction.

BACKGROUND

In both takotsubo cardiomyopathy (TC) and reperfused anterior acute myocardial infarction (AMI), negative T waves commonly appear on the ECG in the subacute phase. This study aimed to clarify the ECG differences between these diseases.

METHODS AND RESULTS

We compared the ECGs with the greatest amplitude of negative T wave from 34 patients with TC and 237 patients with a first reperfused anterior AMI who were admitted within 6 h of symptom onset and who had no abnormal Q-waves on discharge ECG. Time from symptom onset to recording the ECG did not differ between TC and anterior AMI (2.4 ± 1.5 vs. 2.1 ± 2.0 days, P = 0.48). TC was associated with a greater maximal amplitude of negative T wave (1.00 ± 0.44 vs. 0.79 ± 0.46 mV, P = 0.044), and a greater number of leads with negative T waves (9.5 ± 1.0 vs. 6.0 ± 2.1, P<0.001). Negative T waves were consistently observed in leads -aV(R) and V(4-6), whereas negative T waves were rare in lead V(1) in TC. Negative T waves in lead -aV(R) (ie, positive T waves in lead aV(R)) and no negative T waves in lead V(1) identified TC with 94% sensitivity and 95% specificity, representing the highest diagnostic accuracy.

CONCLUSIONS

During the subacute phase, deeper negative T waves were more frequently and broadly distributed, particularly around leads facing the apical region, in TC than in reperfused anterior AMI.