Phasic Analysis of Cardiac Cycle on the Basis of Polygraphic Tracing Apex Cardiogram, Phonocardiogram and Carotid Tracing

Abstract

1) By the use of polygraphic tracing including apex cardiogram, phonocardiogram and indirect carotid tracing, an almost full and precise phasic analysis of the cardiac cycle may be obtained.(2) New methods for the measurement of the ejection period and mechanical systole are presented. Additional Indexing Words: Isovolumic contraction time Initial phase of ventricular contraction Pressure elevation time Ejection period Mechanical systole Protodiastole Isovolumic relaxation time Rapid ventricular filling Slow ventricular filling Active ventricular filling T HE phases of the cardiac cycle and their relationships have been increasingly used in modern cardiology. Cardiac catheterization is not applicable to the measurement of the phases of the cardiac cycle in everyday medical practice.Indirect methods are mainly used for this purpose. But the usual polygraphic tracing including electrocardiogram, phonocardiogram and indirect carotid tracing is not sufficient in this respect. If the apex cardiogram is included and simultaneously recorded with the above mentioned curves, an almost full phasic analysis of the cardiac cycle may be obtained.As is known the apex cardiogram is reliable in timing left-sided events in the cardiac cycle9) which was confirmed by correlating the low-frequency apical vibrations of the apex cardiogram with hemodynamic events within the left heart.10),20) MATERIAL AND METHODSForty normal subjects (19 women and 21 men) were studied. They ranged in age from 14 to 54 years (average age 28 years). Lead II of the electrocardiogram (ECG), an indirect carotid tracing (CT) from the right carotid artery, a left ventricular apex cardiogram (ACG) and a medium frequency phonocardiogram (PCG) were recorded simultaneously with the person reclining in the left lateral decubitus in apnea at the end of a normal expiration. The identification of the origin of the ACG (left or right apex beat) was based on the configuration of the QRS complex