The aim of the project is to develop a method improving eligibility criteria for CRT. To assess the effectiveness and possibilities of the analyzed method, a computer model of the human thorax was built. To estimate the contribution from individual organs to the impedance signal measured on the thorax surface, the simulations were performed. Based on the computed distribution of spatial sensitivity and considering the possibility of determination of selected anatomical points of the chest, the optimal placement of the electrodes was definied. A device for measuring impedance changes and ECG signal has been developed. The device enables simultaneous measurement of impedance changes on 6 measurement channels, using two current sources working on two different frequencies. A measurement set consisted of an apparatus for measuring impedance changes, ECG and a Doppler flow meter. A number of measurements were carried out on both healthy people and patients with implanted pacemakers and patients with right or left bundle branch block. Currently, measured signals are thoroughly analyzed. As a result, a measurement system with a signal processing algorithm will be developed.