0227: Fragmented QRS in patients with STEMI undergoing PCI: relation to ST-segment resolution and determinism

Abstract

fragmented QRS complex (fQRS) is a marker of myocardial scarring and has prognostic significance. ST-segment resolution (STR) in STsegment elevation acute myocardial infarction (STEMI) is characteristic of tissue reperfusion. This study investigates the relationship between fQRS and STR in STEMI patients undergoing primary percutaneous coronary intervention (PCI) and determines the predictors of fQRS. we analyzed the electrocardiograms (ECGs) of 256 patients included in a multicenter prospective STEMI-PCI study. fQRS and STsegment resolution were evaluated upon arrival in the ambulance (ECG-amb) and 1 h post-PCI (ECG-post). Major clinical cardiac events were assessed at 30 days and 6 months. fQRS was present in 33 patients (13.6%) on ECG-amb and in 30 patients (12%) on ECG-post. The presence of fQRS at either time was not associated with STR or clinical outcomes. In a multivariable analysis, the independent predictors of fQRS on ECG-amb were female sex (p=0.04), cardiac troponin Ic level at 72 h (p=0.01), TIMI 0-1 flow rate pre-PCI (p=0.002), and inferior STEMI location (p=0.04). Patients with fQRS on ECG-amb presented a larger necrosed mass on cardiac MRI than patients without fQRS (p=0.04). No predictors of fQRS post-PCI were identified. the presence of fQRS at the time of presentation or 1 h after PCI was not associated with STR. However, fQRS was related to enzymatic infarct size, inferior STEMI location, and low TIMI flow rate.