Clinical Progress

T HE various modalities used in the study of the heart and circulation contribute different types of information. Some, such as electrocardiography and fluoroscopic or roentgenographic study, have such broad spheres of usefulness that they are almost routinely employed. Other diagnostic procedures have not gained wide usage either because of expense of equipment, difficulty in clinical application, specialized nature and limited value of information provided, or because such information as is provided unnecessarily duplicates what may be learned in simpler fashion. It is the object of this survey to appraise the clinical usefulness of ballistocardiography, a technic which records the movements imparted to the body by the forces associated with contraction of the heart, and acceleration and deceleration of blood as it is ejected and moved in the large vessels. Parenthetically it may be remarked that the ballistocardiogram provides, in simple and routinely applicable fashion, a considerable body of useful information not otherwise obtainable; and hence fulfills the criteria of a valuable adjunct in examination of the heart.