title: [Sound spectrographic investigations of heart sounds and murmurs and of the sounds produced by artificial valves (author's transl)].
abstract: The normal heart sounds, murmurs, opening and closing sounds of aortic and mitral valve prostheses were recorded on a tape in order to obtain the highest frequencies which were recordable on the chest wall. Sections of these tapes were analyzed in terms of contour sonagrams. For this purpose six groups were formed and investigated: group I comprised persons without cardiovascular diseases, group II patients with mitral valve failure, group III patients with aortic valve failure, group IV patients with congenital heart disease, group V patients with Starr-Edwards aortic valve prostheses (model 1260) and group VI patients with various mitral valve prostheses. In each of these groups the highest recordable frequencies were measured. The peak frequencies varied widely in regard to frequency range in a comparison of the six groups. The maximum was reached at about 8000 c.p.s. in the case of the sounds of prosthetic valves. Furthermore, sound level examinations of the normal first and second heart sounds, as well as of the opening and closing sounds of the aortic valve prostheses were performed. The highest sound level of all of these sounds was found to lie within the low frequency range of 40 to 100 c.p.s. The results of both the measurements of the peak frequencies and of the maximal sound level were discussed on the basis of the presently accepted theories on the mechanism of heart sounds and murmurs.
mesh_terms: D001021:Aortic Valve; D001022:Aortic Valve Insufficiency / Q000503:physiopathology; D001024:Aortic Valve Stenosis / Q000503:physiopathology; D006326:Heart Auscultation; D006337:Heart Murmurs; D006343:Heart Septal Defects / Q000503:physiopathology; D006347:Heart Sounds; D006350:Heart Valve Prosthesis; D006801:Humans; D008943:Mitral Valve; D008944:Mitral Valve Insufficiency / Q000503:physiopathology; D008946:Mitral Valve Stenosis / Q000503:physiopathology; D010701:Phonocardiography / Q000379:methods*
vernacular_title: Schallspektrographische Untersuchungen von Herztönen, Herzgeräuschen und Tönen künstlicher Klappenprothesen