Usefulness of measurement of carotid arterial wall elasticity distribution in detection of early-stage atherosclerotic lesions caused by cigarette smoking

Purpose. The aim of this study was to evaluate early-stage changes in the arterial wall caused by smoking. Methods. A newly developed real-time ultrasonic measurement system was used to measure the elasticity distribution of the carotid arterial intima-media complex in 53 healthy male volunteers (mean age: 37.6 years), including 27 smokers. Simultaneous measurement of the elasticity distribution and intima-media thickness (IMT) was performed at six locations in the bilateral carotid arteries. Results. The mean elastic modulus in the radial direction (Er) of the carotid arterial area where the IMT was less than 1.1 mm in smokers was larger than that in age-matched nonsmokers. There were no significant correlations between IMT and Er at the same location. However, a significant positive correlation was observed between the maximum IMT (maxIMT) and that of Er (maxEr) in six locations. In smokers, maxEr had a better correlation with the smoking index, and areas of IMT less than 1.1 mm containing harder lesions of Er ≥ 160 kPa were significantly more frequent than in nonsmokers. Conclusion. Measurement of carotid arterial wall elasticity is useful for detecting distortion in the intramural elasticity distribution that occurs prior to IMT thickening caused by smoking as an early-stage atherosclerotic sign.