Phonocardiography and Electrocardiography with a Smartphone

Phonocardiogram, a graphic recording of auscultatory findings of the cardiac sound vibrations, was acquired through an add-on to a stethoscope: a microphone was inserted into the stethoscope tube and connected to a smart device. Phonocardiographic data were synchronised to electrocardiogram, a recording of cardiac electrical activity, that was obtained with a wireless body sensor. Simultaneous phonocardiographic and electrocardiographic data enable a much more detailed understanding of the cardiac function than auscultation of the heart sounds and murmurs with a stethoscope only. Furthermore, the possibility to study phonocardiogram synchronised to electrocardiogram seems a valuable diagnostic tool for the clinician and provides a great teaching material for students. We demonstrate a simple way to construct a device that records simultaneous phonocardiographic and electrocardiographic data, and hence enables a thorough insight into the cardiac electromechanical interactions. Cardiac activity was analysed in 9 volunteers, where timing relations of various electromechanical events were measured.