Ballistocardiographic correlation with invasive and noninvasive characteristics of cardiac ejection and designation of the initial point.

Noninvasive Bcg, ACG, ECC, CP and PCG were correlated simultaneously or by superimposition with the intraventricular and intra-aortic pressure pulse curves. Corresponding alterations in terms of one another have been demonstrated. These made possible delineation of the three phases of initial ejection by marking the points of initial and full opening of the aortic valve cusps (phase 2) in the Bcg, ACG and PCG. Possible prolongation of the interval between them may be seen in the severely diseased, dyskinetic heart which may perhaps be attributed to a 'sinusoidal' Bcg with prolonged H ejection time. The relation of S4 and S3 to mitral leaflet motion and their reflection in the Bcg has been emphasized.