Carotid and aortic stiffness in essential hypertension and their relation with target organ damage: the CATOD study.

OBJECTIVE: The objective of the study is to investigate in the hypertensive population the possible differential association between increased aortic and/or carotid stiffness and organ damage in multiple districts, such as the kidney, the vessels, and the heart. METHODS: In 314 essential hypertensive patients, carotid-femoral pulse wave velocity (cfPWV, by applanation tonometry) and carotid stiffness (from ultrasound images analysis), together with left ventricular hypertrophy, carotid intima-media thickness, urinary albumin-creatinin ratio, and glomerular filtration rate were measured. Increased cfPWV and carotid stiffness were defined according to either international reference values or the 90th percentile of a local control group (110 age and sex-matched healthy individuals). RESULTS: When considering the 90th percentile of a local control group, increased cfPWV was associated with reduced glomerular filtration rate, either when carotid stiffness was increased [odds ratio (OR) 13.27 (confidence limits (CL) 95% 3.86-45.58)] or not [OR 7.39 (CL95% 2.25-24.28)], whereas increased carotid stiffness was associated with left ventricular hypertrophy, either when cfPWV was increased [OR 2.86 (CL95% 1.15-7.09)] or not [OR 2.81 (CL95% 1.13-6.97)]. No association between increased cfPWV or carotid stiffness and target organ damage was found when cutoffs obtained by international reference values were used. The concomitance of both increased cfPWV and carotid stiffness did not have an additive effect on organ damage. CONCLUSION: Aortic and carotid stiffness are differentially associated with target organ damage in hypertensive patients. Regional arterial stiffness as assessed by cfPWV is associated with renal organ damage and local carotid stiffness with cardiac organ damage.

Prognostic value of flow-mediated dilation in patients with systemic lupus erythematosus: a pilot prospective cohort study.

This pilot study evaluated the predictive value of flow-mediated dilation (FMD) for damage accrual in a cohort of SLE patients. Thirty-eight female SLE patients without cardiovascular involvement were enrolled. Clinical history, traditional cardiovascular risk factors, laboratory parameters, disease activity and damage and brachial artery FMD were collected at study entry and after a mean follow-up of 4.5 years. At enrollment, 18 patients (47%) presented active disease; mean FMD was 7.9 ± 3.1%, with no statistically significant differences between women with active and inactive disease. During the follow-up, 3 patients died and 14 accrued organ damage. Baseline FMD did not predict death and damage accrual. FMD showed significant decline over time, which was greater in patients with poor outcome (-3.9% vs -1.9%, p = 0.03). In conclusion, in a cohort of SLE patients, baseline FMD was not predictive of damage accrual. However, the latter was associated with progressive loss of FMD.

Relationship between wave reflection and renal damage in hypertensive patients: a retrospective analysis.

OBJECTIVE: Arterial stiffening has harmful effects; peripheral pulse wave reflections deleteriously increase central pressure, but on the contrary they could also possibly be protective, as the pulse is transmitted to the microcirculation to a lesser extent. The aim of this study was, therefore, to explore the relationship between wave reflection and small vessel damage in the kidney. METHODS: In 216 hypertensive patients, data on renal resistive index, obtained by Doppler ultrasound sampling of the interlobar arteries, as well as augmentation index (AIx) and carotid-to-femoral pulse wave velocity (PWV), were retrospectively analyzed. Reflection magnitude was computed through a triangular flow estimate. RESULTS: AIx and reflection magnitude were positively correlated with resistive index; age, BMI, central pulse pressure, and cholesterol, but not AIx or reflection magnitude, were predictors of resistive index in multivariate analyses. Crossing tertiles of PWV and AIx, resistive index did not differ between patients with high AIx and low PWV (n=25; 0.632 (0.064)) and those with low AIx and high PWV (n=17; 0.645 (0.053)), despite a difference in reflection magnitude (74.9 (6.7) vs. 51.2 (7.3)%; P<0.001). CONCLUSION: Pressure wave reflection is positively correlated with resistive index in a hypertensive population. No negative relationship was found even adjusting for confounders or when it was examined separately from the influence of arterial stiffness. These findings do not support the hypothesis of peripheral wave reflections having a significant protective role for the microcirculation of a low resistance vascular bed such as the kidney.

Functional and structural alterations of large arteries: methodological issues.

Ultrasound assessment of vascular biomarkers has been implemented for screening, prevention and improvement of cardiovascular risk stratification beyond classical risk factors including smoking, diabetes, hypercholesterolemia and hypertension. Thus, the presence of vascular damage at the sub-clinical, asymptomatic stages can identify a "vulnerable" patient, and aid in implementing cardiovascular prevention strategies. Increased intima-media thickness of the common carotid artery is a well-known marker of early atherosclerosis, which significantly correlates with the development of coronary or cerebro-vascular disease. More recently, guidelines for cardiovascular prevention in hypertension also introduced other vascular parameters evaluating both mechanical and functional arterial properties of peripheral arteries. Increased arterial stiffness, which can be detected by ultrasound at the common carotid, has been shown to predict future cardiovascular events and it is already considered a subclinical target organ of hypertensive patients. Even earlier vascular abnormalities such as endothelial dysfunction in the peripheral arteries, detected as reduced flow-mediated dilation of the brachial artery by ultrasound, have also been mentioned for their possible clinical use in the future. This manuscript reviews clinical evidence supporting the use of these different vascular markers for cardiovascular risk stratification, focusing on the need for an accurate, robust and reliable methodology for the assessment of vascular markers, which could improve their predictive value and increase their use in routine clinical practice.