Objective: The aim of this study is to evaluate the relationship between carotid intima-media thickness (IMT) and arterial wall inertial behaviour.
Methods: The simultaneous and noninvasive assessment of the intima-media complex and arterial diameter waveform was performed using high-resolution ultrasonography. The common carotid artery of eleven normotensive subjects (NTA) and eleven mild-to-moderate essential hypertensive patients (HTA) were measured noninvasively using tonometry and an automatic densitometric analysis of B-mode images to obtain IMT and instantaneous pressure (P) and diameter (D) loops. A linear discrete time model was used to estimate the inertial index (K(M)) using a system modelling-identification approach.
Results: In NTA K(M) was 0.333+/-0.256 (mmHg x s2/mm) and IMT 0.643+/-0.061 (mm), whereas in HTA K(M) was 0.798+/-0.590 (P < 0.05) and IMT 0.760+/-0.034 (P < 0.025). When all data of K(M) versus IMT of NTA and HTA were pooled in a linear regression analysis, a correlation coefficient of r = 0.61 (P < 0.05) was obtained.
Conclusion: Wall inertia increase was associated with a higher IMT, suggesting that the intima-media thickening might be partially related to vascular hypertrophy manifested as increase of inertial behaviour.