With the development of technology which enabled a catheter display in the patient’s body without using X-ray radiation, there was an idea that an electrophysiology procedure should be used on high risk patients, such as younger patients, children and pregnant women, without using an X-ray diascope device. (1) The procedure requires the highly experienced operator and a team because manipulation with catheters can cause harm to the patient such as perforation of cardiac structures or blood vessels. Trough the case reports of ablated patients by this zero fluoro method in the period from February 2018 to November 2018 we will present experiences from the Centre for Electrophysiology at the University Hospital Centre Split. Some of the crucial intraprocedural steps will be shown, such as the process of mapping the path to the heart, map processing, recognition of anatomical structures through intracardial electrography, as well as their marking on the map. Our experience is based on 20 patients who underwent the procedure of ablation without using X-ray device. We will especially highlight the case of a patient in the 6th month of pregnancy with atrioventricular nodal reentry tachycardia.