Higher Frequency Phenomena in the Normal Ballistocardiogram

¹ Department, of Psychiatry, State University Medical Center at New York City, and the Department of Medicine, Long Island College Hospital Brooklyn, N. Y.

Physiologic higher frequency phenomena may be demonstrated in ballistocardiograms from normal subjects. These phenomena consist of notches or multiple oscillations on the H-I and K-L segments of the tracings. They may be demonstrated by recording the unfiltered output of an electromagnetic direct-body ballistocardiograph. They become more prominent as the transducer is applied closer to the source of cardiovascular forces, or by passing the output of the transducer through a band pass filter. The time relationship of these oscillations to simultaneously recorded heart sounds suggests their association with the ballistics of the closing heart valves.