Snímání a zpracování vícekanálové fonokardiografie na bázi virtuální instrumentace

Abstract

This thesis introduces a design of a system for the measurement and processing of multichannel phonocardiography (PCG). The PCG signal was measured from seven positions on the thoraxes of 27 subjects. The quality of heart sound detection was evaluated according to the ECG reference. The quality of signals was evaluated per statistic parameters, measured from various positions on the thorax. In positions that were suitable for PCG measurements, the median of correctly detected heart sound was up to 98.5 % for S1 detection and 97.5 % for S2 detection. A delay between the moment of detection of the given sound and reference R peak was disclosed in the accurately detected heart sounds. Statistical tests have shown that the measured delays vary depending on the position of the sensor. The possibility of using this method to measure heart rate (HR) was verified. Comparable results were obtained with reference values in 88.9 % cases when calculating HR using S1 and in 74.1 % cases when calculating HR using S2. This thesis presents areas of the thorax suitable for recording PCG signal, which can be used to measure HR.