Reconstruction of out-of-plane cardiac displacement patterns as observed on the chest wall during various phases of ECG by capacitance transducer.

The out-of-plane displacements due to cardiac action have been measured on the chest wall by an electronic distance measurement technique which is based on the variation of the capacitance between the probe and moving surface. The displacements were measured at 36 locations over the entire cardiac region along with ECG and were directly fed to an IBM PC/AT computer after A/D conversion. From these data, the displacement patterns for the whole region during the complete cardiac cycle could be reconstructed in a perspective view. The sequential analyses of the displacements shows the details of the cardiac events and the results obtained are in agreement with other techniques. The averaged displacements over various regions of the heart for normal subjects have also been presented.