Assessment of left ventricular wall motion

A new method for the assessment of left ventricular wall motion, using a polar analysis, is proposed. The percent shortening of several radii, labeled at 30° intervals, were plotted against Theta (degrees) and an excellent numerical and visual display of wall motion was obtained. Two methods for correcting the systolic upward shifting of apex were tested. The simplest one uses the intersection of the major and minor axes to realign both the end diastolic and the end systolic silhouettes. In the other method ventricular outlines were realigned using anatomical internal markers (diaphragm, ribs, or vertebrae). The intersection of both long axes, whether inside or outside the ventricular silhouettes was used as a pivot point around which the long axes were rolated and the outlines realigned. The mid point of the long axis was used as a common center. There was no statistical difference in the two methods. The data from 14 normal subjects composed a normal percent shortening vs. Theta graph, which can be used as a frame of reference as compared with abnormal hearts.