Heart sound is one of the most important sounds.
It contains many valuable diagnostic information of heart disease. Far before the CHD patients could show obvious symptoms, their heart sounds might have changed. Because a large portion of heart sound energy is in the subsonic area below the audible threshold and most of the messages of coronary heart disease are too weak to be detected by naked ears, clinical application of heart sound is restrained to a narrow extent. Simple, inexpensive and noninvasive detecting system for coronary heart sounds has been expected. In this paper, a PC-based heart sounds gathering and analyzing system of coronary heart disease has been developed.