Permanent cardiac pacing is a method of choice in the treatment of specific arrhythmias and conduction disturbances. Clinical studies show that cardiac performance diminished at the site of impulse spreading. It determines local hypotrophy below the position of the pacing lead (early electric activation) with hypertrophic changes in the opposite lying myocardium (late electric activation). It seems that morphological changes, especially research by intravital methods, so relevant in permanent pacing to today's invasive cardiologist, are not understood in full. In connection with this we decided, on the basis on the echocardiographic examination, to evaluate in detail the morphology of the right ventricle and atrium in patients with permanent pacing. Research was carried out on a group of 124 patients (68 males, 56 females) from 40-93 years of age (avg. 68 +/- 14 yrs): 86 patients had implanted pacemakers or AICD (group I), the control group consisted of 38 patients with other cardiac diseases without any pacemaker devices (group II). We measured echocardiographically the following diameters: end-diastolic and systolic diameters of the right ventricle/atrium in short and long axis, diameter of the tricuspid orifice valve and calculated area of the tricuspid orifice based on a special formula. Regarding the morphometric parameters of the right ventricle and right atrium, we confirmed that all diameters of group I were overshooting in correlation to group II. Those differences, such as RVd-short and -long, RVs-long, RVinflow, RA-long and -short, TRId, were statistically significant. Regarding the area of the tricuspid orifice (TRIa), we did not observe any changes in the two examined groups. We concluded that patients with implanted devices have changes in the morphometric parameters of the right ventricle, atrium and orifice, but they do not depend on the duration of pacemaker implantation.