Background Left Ventricular Ejection Fraction (LVEF) is commonly used to identify patients at high risk of sudden cardiac death and ventricular arrhythmia. However LVEF by Simpson biplane method may be challenging in heart failure patients with severe LV deformation and abnormal wall motion. The aim of the study was to assess the additional value of global longitudinal strain by 2D speckle tracking in predicting the occurrence of ventricular arrhythmia. Methods The study included 45 heart failure patients (86% men, 64 ± 22 years, 60% ischemic) with left ventricular dysfunction (median = 28%, range 13 to 47%) referred for Implantable Cardiac Defibrillator (ICD). LVEF and longitudinal global strain by speckle tracking before ICD implantation was compared to major cardiac outcome (MACE defined by cardiovascular death and ventricular arrhythmia). Results Global strain averaged −7 ± 3% (median = 7%, range −3 to −13%) and correlated with LVEF (r = −0.71, p – 7% (100% vs. 41%, p = 0.06). Conclusion Global longitudinal strain by 2D speckle tracking may improve the identification of patients at risk of ventricular arrhythmia and death in heart failure population with severe left ventricular dysfunction.