The landmark trials MADIT II, SCD-HeFT, and COMPANION in 2002-2005 years have reported their positive results to sudden cardiac death reduction. Since that time the indications for the use of implantable cardioverter-defibrillators (ICDs) have substantially broadened. The occurrence of appropriate ICD therapy differs in the individual trials. We were retrospectively analyzing the occurrence of ventricular tachycardia/ventricular fibrillation (VT/VF) from ICD remote monitoring database (Biotronik Home Monitoring TM, www.biotronik-homemonitoring.com). No significant difference was found between subgroups divided by the implantation indication, the programmed ventricular stimulation, the aggressivity of programmed ventricular stimulation protocol, left ventricular ejection fraction, ICD types, percentage of right ventricular pacing, diabetes mellitus, renal dysfunction and gender. VT/VF occurred statistically significantly more often in patients with non-sustained VT on the preimplant Holter monitoring report in patients with primary preventive indication for postinfarction coronary artery disease but not in primary preventive indication for non-ischemic dilated cardiomyopathy. We observed higher VT/VF occurrence in patients with preimplant syncope or presyncope even higher than in patients after cardiopulmonary resuscitation. There was a visible trend for higher VT/VF occurrence in patients with positive programmed ventricular stimulation especially with less aggressive protocol and in patients with left ventricular ejection fraction of 30% and less. Authors found the preimplant nonsustained ventricular tachycardia (NSVT) on Holter monitoring as the only independent predictor of VT/VF occurrence. (C) 2017 The Czech Society of Cardiology. Published by Elsevier Sp. zo.o. All rights reserved.