Accuracy of subjective and computer‐assisted assessments of angiographic left ventricular regional wall motion

Abstract

To evaluate the accuracy of angiographic methods for analysis of left ventricular regional wall motion, we measured the ability of a carefully performed subjective analysis (three independent observers) and that of three computer-assisted methods (centerline, radial, and area) to detect the presence of significant coronary artery disease. Normal ranges were established in 90 studies showing normal wall motion, and accuracy was tested in a second, consecutive series of 43 ventriculograms. The results show that the subjective method best separated those regions with from those without significant coronary disease. The subjective method also demonstrated sensitivity comparable to the centerline and radial methods. Among the computer-assisted methods, the area method was least sensitive but most specific for both anterior and inferior region coronary disease. The centerline and radial methods were highly sensitive, but less specific. When coronary disease was defined by electrocardiographic Q-waves, the area method had superior accuracy. Further analysis showed the following: 1) For the centerline and radial methods, long-axis reregistration of the end-systolic frame resulted in loss of sensitivity but increased specificity for anterior wall coronary disease, and little change in analysis of the inferior wall; 2) inclusion or exclusion of the apex had little effect on predictive accuracy for anterior wall coronary disease; 3) as expected, sensitivity and specificity results of all methods were dependent on the selection of a normal range cutoff value; but when performance was optimized, the subjective and area methods had a higher overall predictive accuracy than the centerline method; 4) It is likely that all three computer-assisted methods could be calibrated to give indications of degrees of hypokinesis, as their results correlated well with subjective observers' evaluations over the entire range of scores. These results should assist in selection of the optimal method for regional wall motion analysis in clinical and research applications. As currently applied, the area method is the most specific of the computer-assisted methods tested; the centerline and radial methods have highest sensitivity and therefore are most suited to detection of mild degrees of hypokinesis.