Prognostic Implications of Newly Developed T-Wave Inversion after Primary Percutaneous Coronary Intervention in Patients with ST-Segment Elevation Myocardial Infarction

초록

Background T-wave inversion after thrombolytic reperfusion therapy in patients with ST-elevation myocardial infarction (STEMI) has been regarded a sign of spontaneous reperfusion and improved outcomes. We investigated the prognostic value of newly developed T-wave inversion after primary percutaneous coronary intervention (PCI) in STEMI patients. Methods We analyzed consecutive patients with STEMI who underwent primary PCI between January 2010 and May 2014. Newly developed T-wave inversion was defined as new onset of T-wave inversion after the index PCI, without negative T waves on the presenting electrocardiography. The primary endpoint was the occurrence of major adverse cardiovascular events (MACE), including cardiovascular mortality, nonfatal myocardial infarction, and re-hospitalization for heart failure during the follow-up period. Results A total of 291 patients were analyzed in this study. Newly developed T-wave inversion (Ti) was observed in 160 patients (55%); the other 131 (45%) did not show T-wave inversion (T0) after the index PCI. There were no differences in the occurrence of pre-PCI TIMI grade 2 or 3 between the Ti group and the T0 group (23% vs. 24%; p=0.796). However, post-PCI TIMI grade 2 or 3 was slightly more frequent in the Ti group (94% vs. 89%; p=0.072). During the follow-up period, MACE occurred in a total of 42 patients (14%), which consisted of cardiovascular mortality in 24 patients (8%), nonfatal myocardial infarction in 3 patients (1%), and re-hospitalization for heart failure in 15 patients (5%). The cumulative MACE rate was significantly lower in the Ti group than in the T0 group (8% vs. 22%; odds ratio [OR] 0.311; 95% confidential interval [CI] 0.154 to 0.627; p=0.001). In multivariable Cox regression analysis, newly developed T-wave inversion was an independent prognostic factor for MACE (hazard ratio 0.431; 95% CI 0.203 to 0.917; p=0.029). Conclusion Newly developed T-wave inversion during the index admission after pri