TWIN-SCD STEMI is a multicentric prospective, non-randomized pilot study designed to establish a multiparametric model for predicting life-threatening ventricular arrhythmias in patients experiencing their first myocardial infarction. The primary objective of the study is to develop an algorithm with superior predictive performance (sensitivity and specificity) compared to the currently used criterion for the implantation of a cardiac defibrillator, which is a left ventricular ejection fraction (LVEF) of less than 35%.