Objective and subjective analysis of left ventricular angiograms.

Abstract

In order to determine the reproducibility of analyses of left ventriculograms, 35 cineangiograms were evaluated by four observers, two using standard quantitative techniques to determine ventricular volumes and a newly devised quantitative system to evaluate wall motion and two others using only visual inspection of the angiograms. Objective analysis repeated by the same observer correlated well for end-diastolic and end-systolic volumes and ejection fraction (r = .98, .99, respectively) and only one of 105 (1%) wall segments were identified differently. Variability in assessments increased when comparisons were made with a second objective observer. Correlation coefficients for the three volumetric parameters were .93, .98, and .95 and there was disagreement in the assessment of 8% of wall segments. Wide variability was present between an objective and two subjective observers in analyses of end-diastolic volumes (r = .63, .64). Regional wall motion was assessed differently in 19% and 27% of segments, respectively. Though the correlation of objectively and subjectively determined ejection fractions was much better than the correlation for volume (r = .92, .84), it was not as good as the correlation between two objective observers. Occasional errors of clinical significance occurred. We conclude that subjective analysis has a significant error rate and that reproducibility and accuracy of analysis of left ventriculograms require objective analysis.