Measurement of stroke volume by the vibrocardiogram.

An examination has been made of the relationship between stroke volume measured by dye dilution and left ventricular isovolumetric contraction and ejection times as measured by the vibrocardiogram. These studies were performed in 10 normal subjects under postural alterations, and in 11 patients recovering from acute myocardial infarction. gression analyses of the data showed that ejection t h e was highly correlated with stroke volume (r = 0.84), while use of both ejection time and isovolumetric contraction time improved correlation to r = 0.90. Similar correlations were obtained comparing changes in stroke volume with changes in the intervals. simple, non-traumatic method for the estimation of stroke volume. ReIt was concluded that the VbCg provides a MEASUREMENT STROIG VOLUME BY VIBROCARDIOGRAM The need for a simple, non-traumatic technique to measure stroke volume and cardiac output has been greatly intensified by the aerospace program. physical limitations of devices to be used in the in-flight environment preclude the use of direct cardiac output procedures, such as the indicator dilution and Fick techniques. The Our method for determining stroke volume based on the left ventricular isometric contraction and ejection times in dogs was reported in 1965 1. A subsequent comparison with dye dilution studies in human subjects at cardiac catheterization and in dogs using aortic flowmeters confinned that the ratio of these cardiac phases, as measured from pressure curves, provided a means of quantitating stroke volume 2. The present study compares stroke volume measured by the dye dilution technique with left ventricular isovolumetric contraction and ejection times determined from the vibrocardiogram 38 4. normal subjects were examined under conditions of Ten