[Analysis of left ventricular wall motion by computer image processing in patients with or without coronary artery...

Predicting myocardial infarction (MI) due to Kawasaki disease is quite difficult because it occurs exclusively in young infants without recognizable symptoms. This study was conducted to identify some clinical loading tests capable of evaluating cardiac reserve and predicting future occurrences of MI in children with Kawasaki disease. Two-dimensional left ventricular short-axis echocardiograms were processed by fast Fourier transformation (FFT) analysis, which yielded phase images and amplitude images, to evaluate objectively regional wall motion. The phase images obtained from five cases for each of normal coronary arteries, dilated coronary artery lesions, and stenosed arterial lesions had nearly homogeneous color levels of the lower scales, while those obtained from the cases with MI showed the areas composed of several different color levels, and the sites of these lesions corresponded to those of SPECT. The amplitude images obtained from five cases for each of the normal coronary arteries, dilated lesions, and dilated with stenosed lesions showed successive transformation of the color from inside to outside throughout the entire circumference. The cases with MI showed a decrease in the color change at the sites of lesion outlined by SPECT. Three-dimensional displays of MI also showed a decrease in the contraction ratios at the sites of infarction. It was concluded that analyses of color images processed by FFT in the three-dimensional display is helpful for objectively evaluating abnormal left ventricular wall motion.