Exercise-induced T-wave normalization predicts recovery of regional contractile function after anterior myocardial infarction

Aims We investigated the ability of T-wave pseudonormalization and ST-segment elevation, which are demonstrated in infarct-related leads during submaximal exercise testing, to predict late recovery of contractile function. Methods We studied 88 consecutive patients (73 males, mean age 59+/-8 years) with anterior infarction, persistent T-wave inversion and a documented lesion of the proximal segment of the left anterior descending coronary artery. They all underwent 2D-echocardiography on admission, 4 weeks as well as 6 months after myocardial infarction to evaluate the dysfunction score and the ejection fraction. Submaximal (75% of maximal predicted heart rate) exercise testing was performed in 80 patients 2 weeks after myocardial infarction following discontinuation of treatment. Results During exercise testing, 59 of the 88 patients showing negative T-waves on the resting electrocardiogram exhibited pseudonormalization (group A) in at least three adjacent precordial leads, whilst 29 (group B) did not. Patients of group A more frequently exhibited an early creatine kinase peak (41% vs 24%, P<0.05) and residual angiographic perfusion (97% vs 69%, P<0.05). The dysfunction score did not change in group B (from 19+/-7 to 22+/-4), but decreased in group A (from 18+/-4 to 11+/-6, P<0.05). The ejection fraction was similar in the two groups on admission (group A: 48+/-7%, group B: 45+/-10%), but was significantly different at 4-week (52+/-99 vs 42+/-11%, P<0.05) and 6-month follow-up (58+/-9 vs 44+/-10%, P<0.01). The concomitant presence of ST-segment elevation and T-wave normalization showed the highest positive predictive value for left ventricular function recovery (100%). Conclusions T-wave normalization induced by submaximal exercise test is frequently associated with residual perfusion to the infarct area and predicts progressive improvement in regional wall motion, especially if associated with ST-segment elevation. Therefore, these electrocardiographic findings may be used as easily obtainable markers of residual viability that predict late recovery in contractile function.