The investigations were undertaken in order to assess the characteristic features of the isointegral maps obtained from the patients demonstrating on the standard ECG complete and incomplete right bundle branch block (RBBB). The body surface potential mapping (BSPM) procedure was performed using Fukuda Denshi system enabling to record electrocardiographic signals simultaneously from the 87 leads arranged over anterior and posterior thoracic surfaces. The isointegral maps of QRST, QRS, early portion of QRS complex (from QRS onset to R wave peak), and of late portion of QRS (from R wave peak to QRS offset) were created. The distribution of extrema (maxima and minima) was found to be specific for RBBB cases and the characteristic differences between RBBB group and the controls were observed.