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We traced left ventricular contours, frame-by-frame throughout systole and diastole, of normal sinus beats from 30 degrees right anterior oblique ventriculograms from 32 normal patients. We separated both systole and diastole into 19 equal time intervals each and calculated regional lengths (R), normalized by both end-diastole length and relative time interval (T) in systole and diastole and diastole, for the middle inferior wall, distal inferior wall, apex, distal anterior wall, middle anterior wall, and proximal anterior wall. We also computed the relative velocities of R, delta R/ delta T, over each quarter of systole and diastole. Comparing systole with diastole, we found significant differences between paired values of R at all regions except the distal inferior wall, but these differences were not the same between regions. Between regions, mean R and delta R/ delta T values were significantly different as early as the first quarter of systole. Within a region, there were significant differences between mean R and delta R/ delta T values over intervals as short as one-fourth of systole or diastole. Thus, there is no homogeneity between regions in normal wall motion in both systole and diastole. This normal lack of homogeneity has important clinical implications for identifying abnormal wall motion in individual patients from ventriculographic measurements, and for using the information present in the diastole portion of the ventriculogram to characterize normal segmental function.

We evaluated changes in ventricular wall motion after surgery by comparing smoothed, filtered measurements of regional percent shortening (RPS) from right anterior oblique ventriculograms in 37 patients before and after surgery. After surgery there was a significant (p less than 0.05) decrease in the number of regions with hypokinetic wall motion. The distribution of RPS values was also different (p less than 0.005). However, the mean value of RPS for the surgery group as a whole was not significantly altered. These data were contrasted with RPS data from 11 control patients, who were each studied twice but did not have surgical intervention. Similar analysis of the control group did not show any significant change between studies in the number of hypokinetic regions, and the distributions of RPS for the first and second angiograms were not different. We found a 10.3% absolute mean change in repeated measurements of RPS in the control group. We conclude that significant changes occurred after surgery that were not evident in the control group, and the amount of variability in repeated measurements of RPS suggests that analysis should be applied to group rather than individual data.

To investigate whether a fixed external reference system should be used to most accurately describe regional left ventricular wall motion, we used vectors to analyze a simple model of ventricular contraction. If measured in a fixed external reference system, motion of implanted radiopaque midwall markers may contain translational as well as contractile components. Therefore, comparisons of different reference systems that use marker motion measured in a fixed reference system as a standard will be biased unless proper corrections are included. We conclude that evidence to data does not indicate that the use of a fixed reference system is superior to other methods for analyzing regional ventricular wall motion.