Abstract
The quantitative evaluation of heart motional function is important for diagnosis of heart disease. Doctors evaluate the motional function using indexes such as the changing rate of myocardial thickness and the changing rate of ventricular volume. Our research group has developed “Correlation Method Weighted with Confidence (CMWC)”. CMWC is a tracking method for regional heart muscle from ultrasonic radio frequency (RF) signals in order to measure the motion in the myocardium correctly. Using the tracking method, we were able to measure the motion quantitatively from RF signals with low noise. In this study, first, we statistically investigated the motion of normal heart muscle using successful results of CMWC. At the next, we proposed three indexes for evaluation of heart motional function. The first index was based on the sift velocity of normal heart muscle. The second index was based on the changing rate of myocardial thickness. The third index was the linear combination between the first index and the second index. At the last, we compared the accuracy of diagnosis between proposed indexes and changing rate of myocardial thickness by ROC analysis. As a result, the area under the ROC curve was 0.95 at the first index, 0.91 at the second index, 0.97 at the third index, and 0.93 at the changing rate of myocardial thickness. We were able to propose an index with higher accuracy than the changing rate of myocardial thickness.