Precordial low-frequency displacements of the thoracic wall method of recording and registration

Abstract

1. 1. A description is given of a new method of recording precordial movements of the chest wall, with illustrations depicting the apparatus and the mode of application to the subject to be examined. A number of curves obtained by this method are presented in addition. 2. 2. The authors believe that the new method offers the following advantages over conventional recording methods: (a) small integrating surface of the transducer, as a result of which precordial displacements of the chest wall are locally measured, whereas other transducers measure a contribution from several precordial sites; (b) proportional and reproducible recording of precordial displacements caused by the heart action; (c) instant registration, frequency range, and high sensitivity because of the physical characteristics of the transducer and the measuring apparatus. 3. 3. Results and interpretations obtained from hearts with a normal and a pathophysiologic function will be presented in a subsequent publication.