Aim. To examine the impact of late gadolinium enhancement (LGE) in the left ventricular myocardium on magnetic resonance imaging (MRI) on overall mortality and the phases of arrhythmic events in patients with ischemic cardiomyopathy and implantable cardioverter defibrillator (ICD).Methods. This was a single-center retrospective study. A total of 382 medical records of patients from the period between 2019 and 2022, who underwent ICD implantation as part of primary prevention of sudden cardiac death at National Centre of Cardiovascular Surgery, were analyzed. Seventy-four patients were selected for the study. Observation was conducted through in-person examinations and remote monitoring. Endpoints evaluated included overall mortality and arrhythmic events. The cause of death was determined based on the “Promed” medical database. Patients who reached a specific endpoint constituted the case group, while those who did not reach any endpoint formed the control group.Results. During the observation period, arrhythmic events were registered in 26 patients (35.1%), with a total of 27.1±13.2 events. Twenty-one patients (28.4%) deceased. In univariate regression analysis, the presence of LGE, the extent of LGE (%), and the number of segments with LGE served as predictors of ICD activation and overall mortality. Two multivariate logistic regression models were constructed. ROC curves were used to determine the quality of the regression model, with an area under the curve of 0.807 for ICD activation and 0.789 for mortality. The highest sensitivity and specificity of the method were observed with a LGE value equal to or greater than 14% for ICD activation (sensitivity 81%, specificity 75%) and 26% for overall mortality (sensitivity 89%, specificity 64%).Conclusion. Substantiated ICD activations (shock/antitachycardia pacing) were observed in 35.1% of cases, and the overall mortality rate was 28.4%. The association between ICD activation and the extent of LGE occurred when LGE was >14%. The association between overall mortality and the extent of LGE occurred when LGE was >26%.