A New Combined Stethoscope Chest Piece

Because of the variable qualities of different cardiac murmurs, it has been evident for a considerable time that no single stethoscope chest piece is satisfactory in transmitting all the sounds produced in the heart. Ideally, a stethoscope that could be made to vary its optimal resonating qualities between wide limits in order to respond correctly to both high and low pitched sounds would be the most sensitive instrument to use. Practically, such instruments are cumbersome and complicated. For clinical uses two forms of stethoscope chest piece have been found adequate in transmitting heart sounds and murmurs, except in the rare instances in which the naked ear is more satisfactory in responding to high pitched, blowing murmurs, such as those of aortic regurgitation. These two chest pieces are the bell type, which is most useful for low pitched murmurs, and the Bowles type, which registers high pitched murmurs more accurately. The