Introduction and objective: The early inversion of T waves in patients with acute myocardial infarction has recently been related to a better left ventricular function and a more favourable evolution, contrary to what happens in the unstable angina. On the other hand, the significance of the appearance of deep negative T waves in the early phase of some acute myocardial infarction is not known. The aim of this study is to evaluate its relation with the existing myocardial damage and the underlying coronary artery disease extension in anterior some with Q wave.
Methods: 48 patients with a first anterior Q-wave acute myocardial infarction, thrombolized or not, admitted to hospital with an evolution of less than 24 hours, and with a coronariography performed before discharge were analyzed. Giant negative T waves were defined as those which were 8 mm or more from baseline.
Results: 17 of the 48 patients presented giant negative T waves (T-group) and 31 did not (N-group). In the T-group patients, the size of the negative T wave was 11.29 +/- 2.86 mm and the number of precordial leads with negative T waves was 4.35 +/- 1.57. There were no differences between both groups in variables such as sex, coronary risk factors, and other basal characteristics. The T-group patients were younger, had lower peak-CK, CK-MB and LDH levels and presented greater recovery of R waves during the follow-up, the differences being significant with the N-group patients. The left ventricular ejection fraction was higher (56.3 +/- 13.4 vs 42 +/- 12%; p < 0.001) and the number of affected coronary vessels was lower in the T-group (1.12 vs 1.64; p < 0.01); there were no differences in the localization or severity of coronary lesions, nor in the frequency of postinfarction myocardial angina. None of the patients in the T-group were Killip > I, while this situation occurred in 38.7% of the N-group patients.
Conclusions: The appearance of giant negative T waves in the acute or early phase of Q-wave anterior acute myocardial infarction is associated with a smaller infarct size, lower functional deterioration and less extension of the underlying coronary disease.