Usefulness of T wave inversion in leads with ST elevation on the presenting electrocardiogram to predict spontaneous reperfusion in patients with anterior ST elevation acute myocardial infarction.

Abstract

Inversion of the T waves (T-) in electrocardiographic leads with ST-segment elevation after the initiation of reperfusion therapy is considered a sign of reperfusion. However, the significance of T- on presentation before the initiation of reperfusion therapy is unclear. The aim of this study was to assess whether T- on presentation predicts patency of the infarct-related artery in patients with acute ST-segment elevation myocardial infarctions (STEMIs) who undergo primary percutaneous interventions. The medical records, electrocardiograms, and angiographic findings of 209 consecutive patients who underwent emergent coronary angiography as part of primary percutaneous coronary intervention protocol activation for STEMI were reviewed. A total of 179 patients (86%) had positive T waves (T+), 16 (8%) had biphasic T waves (T+/-), and 14 (7%) had T-. Patency of the infarct-related artery (Thrombolysis In Myocardial Infarction [TIMI] flow grades 2 and 3) was seen in 64.3% of the patients in the T- group compared with only 31.2% in the T+/- group and 19.0% in the T+ group (p <0.001). Among patients with anterior STEMI, patency of the infarct-related artery was seen in all 7 patients in the T- group, compared with 50% of the 4 patients in the T+/- group and 10.1% of the 79 patients in the T+ group (p <0.001). There were no significant differences in TIMI flow grade among the groups in patients with nonanterior STEMIs (p = 0.985). In conclusion, T- in the leads with maximal ST-segment elevation on the presenting electrocardiogram was associated with higher prevalence of patency of the infarct-related artery before intervention (64.3%), especially in patients with anterior STEMIs (100%).