上腕圧迫による近赤外光を用いたヒト手指透過血管像変化と脈波伝播速度との関係

抄録

We measured the change in brightness of vascular images taken with near-infrared light during upper arm compression, and brachial-ankle pulse wave velocity (baPWV), which was calculated from the difference in pulse-wave transit time between the brachial artery and the ankle artery. The correlation between these measures was determined in 52 male subjects of different ages (22 to 66 years). The dorsal surface of the proximal interphalangeal joint of the right index finger was illuminated with near-infrared light (wavelength: 850 nm), and a vascular image was taken of the palmar side with a CCD camera during cuff compression (80 mmHg). The time it took for the change in brightness to reach 50% of the convergence value (half-convergence time) was calculated based on the measured change in brightness. The half-convergence time indicates venous compliance, and baPWV indicates arterial compliance. There was a negative correlation between the half-convergence time and baPWV (r = -0.688, p < 0.001). This correlation may be accounted for by age-related changes in the elastin and collagen that comprise the vascular walls of the artery and the vein. We consider these changes to have a similar influence on the half-convergence time and baPWV. We could therefore estimate arterial compliance by measuring venous compliance.