ENHANCED AUSCULTATION WITH A NEW GRAPHIC DISPLAY SYSTEM

Background: To provide an objective method to support and teach auscul tation, a new portable system (graphic display system) was evaluated f or graphic display and printing of heart sounds. Methods: Ninety-one p atients from three institutions, with a variety of heart sound abnorma lities, were studied by two examiners. A graphic recording was made in each and compared with the auscultatory findings. Results: The findin gs of the graphic system confirmed the auscultatory impressions of bot h examiners in 77 (85%) of the 91 cases. Brief sound transients, such as split second sounds and ejection sounds, third heart sounds, and pr osthetic opening and closing sounds, were all regularly recorded with the graphic system, often allowing resolution when examiners were in d isagreement. Graphic recordings commonly were at variance with examine rs in detecting fourth sounds, possibly because of examiners' difficul ty in distinguishing these from split first sounds as well as limitati ons of the graphic system itself. High-pitched murmurs of low intensit y (< grade 2), as exemplified by those of aortic and mitral regurgitat ion, were occasionally missed by the graphic system, probably because of baseline interference by background noise. Conclusions: The graphic display system can often provide more information than can be obtaine d by standard auscultation alone, especially in the detection of low-f requency and multiple sounds, and in the accurate timing of intervals. It is often unable to detect soft high-frequency murmurs. Permanent r ecords allow for more objective comparison of the auscultatory finding s of various examiners at different times. This system provides an exc ellent means by which auscultation skills may be taught or enhanced, e specially since its speed and portability allow immediate feedback for comparison with auditory perceptions.