Primary endpoint (variable):~The resolution of myocardial stunning at 48 hours (StunningRes48h).~The proportion of stunning that has resolved at 48 hours will be calculated according to the formula:~StunningRes48h = (%AkinesiaBaseline - %Akinesia48h) / (%AkinesiaBaseline - %Akinesia30days) where %AkinesiaT is defined as the endocardial length of the akinetic myocardium measured in end-diastole divided by the total endocardial length measured in end-diastole in the 2- and 4-chamber view, at time T (T= 48h or 30 days)~Secondary endpoint(s) (variables):~Infarct size at 6 months, as assessed by cardiac magnetic resonance imaging (magnetic resonance imaging).~Ejection fraction days 1, 2, 3, 7, 14, 30 and 6 months.~Any sustained ventricular tachycardia or fibrillation within 72 hours (safety endpoint; binary)~Any high-grade atrioventricular block or sinus arrest within 72 hours (safety endpoint; binary)~Implantation of cardiac assist device within 72 hours (binary)~Stroke within 6 months (binary)~All-cause mortality within 6 months~Heart failure rehospitalization within 6 months*~Worsening in-hospital heart failure ≥12 hours after PCI#~Composite of any worsening in-hospital heart failure ≥12 hours after PCI or heart failure rehospitalization within 6 months.~Defined as re-admission to hospital after discharge, with a total length of admission ≥24 hours, documented worsening of heart failure signs or symptoms (e.g. worsening dyspnea, fatigue, edema/fluid overload, pulmonary venous distension or signs of pulmonary edema on X-ray), with administration of intravenous diuretic or inotropic drugs, ultrafiltration, non-invasive ventilation or mechanical assist device.~Defined as intensification of heart failure therapy due to worsening heart failure signs or symptoms (as above; including intravenous diuretic, inotropic or vasopressor drugs, non-invasive ventilation or mechanical assist device).
The aim of this study is to evaluate the effect of adenosine on the recovery of myocardial akinesia in ST-elevation myocardial infarction (STEMI). The study is a single-center randomized clinical trial intending to include 90 patients.~The objective of the study is to investigate whether treatment with adenosine hastens recovery of myocardial akinesia and improves cardiac function at 48 hours in patients with STEMI.