P.029 Mechanical Characteristics of Carotid Artery Walls in Relation with Prevalent Cardiovascular Diseases

Abstract

Background

Cardiovascular diseases (CVD) modify the mechanical characteristics of arteries. A better understanding of the corresponding changes will improve diagnostic possibilities.

Methods

With a 7.5 MHz linear array ultrasound system, the left and right common carotid artery of 97 subjects (54m; age 36-95y, average 65y) were assessed. The displacement of the arterial walls was calculated for half-overlapping windows of 20 ms by 0.3 mm, at maximum wall deformation rate, together with their standard deviations across the echo lines. The ultrasound images were separately processed to measure manually intima media thickness (IMT) and IMT-inhomogeneity.

Results

82% of the patients were hypertensive, 37% of the patients were diagnosed with CVD, all patients had high cholesterol and LDL with low HDL levels. 64% of the patients presented an inhomogeneous posterior wall structure. The maximum strain rate varied between 0.5%/ms and 4.3%/ms with an average of 2%/ms. Distension at peak acceleration varied between 0.04 and 0.5 mm (average 0.24 mm). Patients with a high standard deviation of strain rate and distension had an increased IMT (560 mm vs 475 ± 10 mm), with an inhomogeneity between 2 and 19%.

Conclusions

The present investigation shows that the standard deviations of distension and strain rate are indicative for an irregular wall-lumen transition. The results underline the necessity of detailed analysis of arterial wall characteristics in patients with increased CVD risk.