Local carotid stiffness and intima-media thickness assessment by a novel ultrasound-based system in essential hypertension

Objective: To evaluate local carotid stiffness (CS) and intima-medial thickness (C-IMT) in hypertensive patients with different cardiovascular risk profile, using a new user-friendly ultrasound-based system, previously validated vs. RF-based echotracking device. Methods: We investigated a population with different cardiovascular risk: 45 healthy normotensives (NT), 90 non-diabetic hypertensives (HT), and 48 patients with hypertension and type-2 diabetes (DM). Framingham risk factor score (FRS) was calculated. PWV was assessed by applanation tonometry. The relative stroke change in diameter (Delta D) and C-IMT were measured on carotid scans. Distensibility coefficient (DC) was calculated as Delta A/(A*Delta P), where A = diastolic lumen area, Delta A = stroke change in lumen area, and Delta P = carotid pulse pressure. CS (m/s) was calculated as (rho*DC) - 1/2 (rho = blood density). Results: CS, C-IMT, PWV were significantly increased in HT and DM vs. NT. C-IMT and PWV were significantly higher in DM than HT. Delta D and DC were significantly lower in HT and DM vs. NT. FRS >= 10% group showed increased carotid diameter, C-IMT and CS than the FRS <10%. FRS was (p < 0.001) correlated with CS (r = 0.35); Delta D (r = -0.36), DC (r = 0.35), C-IMT (r = 0.48), PWV (r = 0.38). CS correlated (p < 0.05) with PWV in the entire population (r = 0.37), in the NT (r = 0.35), in the HT and DM (r = 0.20). PWV (r = 0.50) and CS (r = 0.33) were correlated with age. Determinants of aortic and carotid stiffness were identified by multivariate stepwise analysis. Conclusions: The proposed B-mode ultrasound-based system is a reliable and user-friendly method that could serve to investigate the predictive value of CS for cardiovascular events in future large clinical studies. (C) 2012 Elsevier Ireland Ltd. All rights reserved.