Transient giant negative T wave in acute anterior myocardial infarction predicts R wave recovery and preservation of left ventricular function

Objective-To investigate the value of a giant negative T wave (greater than or equal to 1.0 mV) in precordial leads of 12-lead electrocardiograms in the acute phase of Q wave myocardial infarction as a predictor of myocardial salvage. Methods-Coronary angiographic and electrocardiographic findings, left ventricular ejection fraction in the chronic stage, and levels of cardiac enzymes were compared in patients with myocardial infarction with (group GNT, n = 31) and without (group N, n = 20) a giant negative T wave. GNT patients were divided into two subgroups according to the presence (GNT:R[+], n = 10) or absence (GNT: R[-], n = 21) of R wave recovery with an amplitude greater than or equal to 0.1 mV in at least one lead that had shown Q waves. Results-The maximum level of creatine kinase and the total creatine kinase were lower in group GNT compared with group N (P < 0.05). The left ventricular ejection fraction was higher in group GNT than in group N (P < 0.05). The maximum creatine kinase and total creatine kinase were lower in GNT:R(+) than in GNT:R(-) (P < 0.01). The left ventricular ejection fraction was higher in GNT:R(+) than in GNT:R(-) (P < 0.01). The frequency of R wave recovery was significantly higher when giant negative T waves appeared within 100 h of myocardial infarction or when the maximum potential was greater than or equal to 1.4 mV. The appearance of a giant negative T wave greater than or equal to 1.4 mV had a sensitivity of 90%, a specificity of 71.4%, a diagnostic accuracy of 77.4%, a positive predictive value of 60%, and a negative predictive value of 93.8% for prediction of R wave recovery. Conclusions-The appearance of a giant negative T wave, especially within 100 h of the onset of myocardial infarction, with a maximum potential of greater than or equal to 1.4 mV, may predict a reappearance of the R wave and a better left ventricular function in patients in the chronic stage of anterior myocardial infarction.