The role of baseline and post-procedural frontal plane QRS-T angles for cardiac risk assessment in patients with acute STEMI.

Abstract

To our knowledge, no study so far investigated the importance of post-procedural frontal QRS-T angle f(QRS-T) in ST segment elevation myocardial infarction (STEMI). The aim of our study was to investigate the role of baseline and post-procedural f(QRS-T) angles for determining high risk STEMI patients, and the success of reperfusion. A total of 248 patients with first acute STEMI that underwent primary percutaneous coronary intervention (pPCI) or thrombolytic therapy (TT) between 2013 and 2014 were included in this study. Baseline f(QRS-T) angle was defined as the angle which measured from the first ECG at the time of hospital admission. Post-procedural (QRS-T) angle was defined according to the treatment strategy as follows: the angle which measured from the post-PCI ECG in patients treated with pPCI; the angle which measured from the ECG taken 90min after onset of therapy in patients treated with TT. The baseline (101.9°±48.0 vs. 72.1°±49.1, p=0.014) and post-procedural f(QRS-T) angles (95.7°±48.1 vs. 58.1°±47.1, p=0.002) were significantly higher in patients who developed in-hospital mortality than the patients who did not develop in-hospital mortality. Also, f(QRS-T) angle measured at 90min was significantly lower in patients with successful thrombolysis group compared to failed thrombolysis group (53.2°±42.8 vs. 77.3°±52.9, p=0.033), whereas baseline f(QRS-T) angle was similar between two groups (78.6°±53.4 vs. 78.9°±54.0, p=0.976). Multivariate analysis showed that post-procedural f(QRS-T) angle ≥89.6° (odds ratio: 3.541, 95% confidence interval: 1.235-10.154, p=0.019), but not baseline f(QRS-T) angle, was independent predictor of in-hospital mortality. f(QRS-T) angle may be used as a beneficial tool for determining high risk patients in acute STEMI. Unlike previous studies, we showed for the first time that that post-procedural f(QRS-T) can predict in-hospital mortality and TT failure.