Correlative analysis of vectorcardiograms and serial instantaneous surface potential maps in normal young men

This study compared and analyzed the similarities and disparities between the instantaneous body surface potential maps (BSM's) and vectorcardiograms (VCG's) obtained from 30 healthy young men. Changes in the VCG from that of the classic normal usually consisted of scalloping of the smooth arch in the VCG loops and usually occurred in inferior and posterior loops after 35 msec. Changes in the BSM that differed from what we considered the normal were usually double positive peaks or double negative valleys. There was good correlation between the BSM and the VCG as long as the heart acted as a single dipole. With multiple dipolar activity of the heart, the BSM usually showed double sinks or peaks of voltage representing the more complex heart activity. During this time the VCG usually showed scalloping.We concluded that much of the multipolar activity of the heart centers around the various times of electrical breakthrough to the epicardium in the normal sequence of depolarization of the heart. We feel that this study has started a basis to help clarify the relationships between inflections and indentations of the VCG and the complex surface activity in detailed potential maps which will be important in distinguishing these normal changes from the more common notching and scalloping with known heart disease.