Due to developments in pacemaker technology, implanted pacemakers do not mean an absolute contraindication for MRI examination. However, there are several aspects of MRI examinations that should be considered for safety reasons in pacemaker patients. Based on literature data and own experiments, the safety protocol of MRI examination in pacemaker-implanted patients is described. The interaction of pacemakers--frequently implanted in Hungary--with MR scanners of 0,35 and 1,5 T was studied in vitro. In addition, the cardiac MRI examination of two pacemaker patients is presented. -ICD pacemakers showed strong interaction with static and changing magnetic field that affected pacemaker performance significantly. MRI examination can be safely performed in pacemaker-independent patients. Based on our in vitro and in vivo measurements, MRI examination is still contraindicated in pacemaker-dependent patients. In pacemaker-independent patients blood pressure, ECG monitoring and pulsoximetry are absolutely necessary, in addition, equipment for resuscitation should be available. Pacemaker should be specifically programmed before MRI examination and parameters and functionality should be checked in details afterwards.