Katayama K, Guth B D, Widmann T F, Lee J D, Seitelberger R, Peterson K L
Department of Medicine, School of Medicine, University of California, San Diego, La Jolla.
Jpn Circ J. 1988 Jul;52(7):607-16. doi: 10.1253/jcj.52.607.
To determine whether or not the first harmonic of a temporal Fourier transform, applied pixel-by-pixel on time-intensity curves, can detect the subtle wall motion abnormalities due to ischemia, 6 dogs were instrumented with a micromanometer in the left ventricles, a hydraulic cuff occluder around the circumflex coronary artery, and sonomicrometers on the inferior (ischemic) and anterior (non-ischemic) walls. Left ventricular images, obtained after contrast injection via the pulmonary artery, were compared with dimension signals in control and 3 progressive levels of coronary stenosis (Stenosis I, II and III). Normalized, digital functional images (512 x 512 matrix, 256 shades of gray/pixel) were divided into anterior, apical, and inferior areas to acquire regional mean phase (degrees) and amplitude (intensity units) values. After inducing stenosis, phase in ischemic region significantly increased at all 3 levels of stenosis, whereas amplitude significantly decreased at Stenosis II and III. However, amplitude images showed clearly the topographic site of ischemia. There was a progressive increase in phase and decrease in amplitude in ischemic areas as the percent wall thickening (%WTh) fell (phase vs. %WTh: r = -0.55, p less than 0.005; amplitude vs. %WTh: r = 0.71, p less than 0.001). Heart rate and peak systolic pressure showed no significant changes during stenosis. We conclude that quantitative functional images, generated from a temporal Fourier transform, are sensitive to the detection of left ventricular regional wall motion abnormalities during mild, moderate, and severe degrees of ischemia.
为了确定逐像素应用于时间-强度曲线的时间傅里叶变换的一次谐波是否能够检测出由缺血引起的细微壁运动异常，对6只犬进行了如下操作：在左心室植入微测压计，在左旋支冠状动脉周围放置液压袖带闭塞器，并在下心壁（缺血区）和前壁（非缺血区）放置超声测距仪。通过肺动脉注射造影剂后获得的左心室图像与对照及3个渐进性冠状动脉狭窄水平（狭窄I、II和III）下的尺寸信号进行比较。将归一化的数字功能图像（512×512矩阵，每个像素256级灰度）分为前壁、心尖和下壁区域，以获取区域平均相位（度）和振幅（强度单位）值。诱导狭窄后，在所有3个狭窄水平下，缺血区域的相位均显著增加，而在狭窄II和III时，振幅显著降低。然而，振幅图像清晰地显示了缺血的地形部位。随着壁增厚百分比（%WTh）下降，缺血区域的相位逐渐增加而振幅逐渐降低（相位与%WTh：r = -0.55，p < 0.005；振幅与%WTh：r = 0.71，p < 0.001）。狭窄过程中心率和收缩压峰值无显著变化。我们得出结论，由时间傅里叶变换生成的定量功能图像对轻度、中度和重度缺血期间左心室区域壁运动异常的检测很敏感。
