Abstract 3267: Positive T Wave in Lead aVR and No Negative T Wave in Lead V1 Distinguishes Tako-tsubo Cardiomyopathy From Recanalized Anterior Acute Myocardial Infarction
Negative T wave (Neg T) after ST-segment elevation in precordial leads often occurs in tako-tsubo cardiomyopathy (TC), but is also observed in recanalized anterior acute myocardial infarction (ant AMI). We compared Neg T between 33 patients with TC and 342 with a first ant AMI within 6 h after symptom onset. In all patients with ant AMI, occlusion and TIMI 3 flow of the left anterior descending coronary artery were documented by emergency coronary angiography. Patients with TC were older (70±11 vs 61±11 years, p<0.01), more likely to be women (75% vs 15%, p<0.01), and had a lower peak creatine kinase level (409±533 vs 3684±2623 mU/ml, p<0.01) than those with ant AMI. After admission, ECGs with the greatest amplitude of Neg T were analyzed. Time from admission to recording ECG was similar between the 2 groups (2.5±1.5 vs 2.0±1.8 days). Patients with TC had a smaller number of leads with abnormal Q waves (1.0±2.1 vs 3.4±1.9, p<0.01), a longer maximal QTc interval (641±94 vs 580±84 ms, p<0.01), and a greater amplitude of maximal Neg T (9±5 vs 7±4 mm, p<0.01). The distribution of Neg T ≥1.0 mm is shown in Figure⇓, using the Cabrera sequence to display limb leads. In patients with TC, Neg T was observed consistently in leads -aVR and V4 – 6, but rarely in lead V1. Neg T in lead -aVR and no Neg T in lead V1 was observed in 94% of patients with TC, as compared with only 6% of those with ant AMI (p<0.001). This finding identified TC with 94% sensitivity, 94% specificity, and 94% predictive accuracy, which were higher than those of other ECG variables. In conclusion, the presence of Neg T in lead -aVR (i.e., positive T wave in lead aVR) and the absence of Neg T in lead V1 simply but accurately differentiates TC from recanalized ant AMI.