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Preeclampsia/eclampsia syndrome, a major cause of maternal mortality and morbidity, has been recognized as a condition with a globally impaired endothelial function (EF). The possibility of identifying early subclinical endothelial damage during pregnancy could be of value in classifying the different hypertensive states of pregnancy, and have a positive impact in the understanding of this syndrome, as well as on the appropriate treatment of these patients. Reactive hyperemia-related changes in carotid-radial pulse wave velocity (PWVcr) were proposed as an alternative tool for the evaluation of EF in patients with cardiovascular risk factors. If impaired EF, which follows hypertensive disorders of pregnancy can be assessed using PWVcr changes remains still unknown. Aims: To assess and compare reactive hyperemia-related changes in PWVcr and FMD in pregnant women (healthy and with hypertensive disorders) and non pregnant women. Methods: Healthy pregnant (HP; n=13), preeclamptic (PE; n=7), non-proteinuric hypertensive (NPH; n=6) and non-pregnant (NP; n=32) women were included. Left PWVcr (strain gauge mechano-transducers), left brachial arterial diameter (B-Mode ultrasound) and blood flow velocity (Doppler ultrasound) were measured before (baseline) and after the transient ischemia of the left forearm were determined. Results: One minute after the cuff deflation, PWVcr decreased in HP (6.9 ± 1.5 to 6.0 ± 0.9 m/s, p

Carotid intima-media thickness (CIMT) is a well-established subclinical marker of atherosclerosis. Non-invasive vascular evaluation has emerged as a useful tool to aid in individual cardiovascular (CV) risk stratification and diagnose. The use of CIMT in CV risk stratification requires knowing the expected reference values for the population studied. Our aim were: a) to evaluate the relationship between aging and CIMT, b) to analyze gender and side (right vs left) related-differences in CIMT and c) to determine the CIMT reference values for an Uruguayan population taking into account aging-related CIMT changes. Methods: 367 asymptomatic subjects without known CV disease or risk factors were included in the study. Subjects were divided into six age groups. High-resolution B-mode ultrasound images of both (right and left) common carotid arteries were obtained based on the techniques and recommendations described in international consensus. Results: No significant age-related differences in CIMT between men and women were observed. The mean left CIMT was thicker compared with right CIMT in groups 4, 5 and 6. However, there were no significant differences in those groups. The nomogram model was constructed from data base, in which the 95% confidence interval was considered. Diagnosis thresholds were determined as well. Conclusion: We define reference values of CIMT for our population using gold standard techniques which contributes to standard techniques which contributes to an improved insight into clinical practice and can be used routinely for evaluation.

Flow-mediated dilatation (FMD) is the most accepted technique for the evaluation of endothelial function. However, it has been show a great inter-subject variability limiting its clinical use. Carotid-radial pulse wave velocity (PWVcr) was proposed as an alternative tool for the evaluation of endothelial function. At the present, there is no doubt that PWVcr reduces its values in response to reactive hyperemia test (RHT) in healthy subjects. Aims: a) to determine simultaneously the temporal profile of FMD, PWVcr and shear rate in response to RHT and b) to describe and analyze how subjects “FMD responders” or “non-responders” behave regards to PWVcr changes. Methods: 34 healthy young subjects were included. The PWVcr (strain gauge mechanotransducers), brachial diameter (B-Mode ultrasound and blood flow velocity (Doppler ultrasound) were measured before (baseline) the cuff was inflated and after its deflation (5 minutes). 10th percentiles FMD and PWVcr changes in the population were used for the definition of the subjects (“responders and non-responders”). Results: Changes in PWVcr, brachial arterial diameter and shear rate were evidenced after the cuff release (p

Carotid-femoral pulse wave velocity (PWV) has emerged as the gold standard for non-invasive evaluation of aortic stiffness. However, the absence of standardized methodologies of study and lack of normal and references values have limited wider implementation of PWV in clinical practice. In this work normal PWV levels were determined in a Uruguayan population and the obtained values were analyzed taking into account data from other populations. The differences between the 'real' PWV levels and the PWV calculated using different wave detection algorithms and path lengths were assessed, and compared the taking into account the changes in PWV with aging.The Uruguayan population showed a rate of PWV increase comparable to that reported previously in non-hypertensive European subjects, although overall, PWV values were approximately 2 m/s higher in the Uruguayan population. The different approaches used to calculate the PWV showed differences in their availability to follow aging-variations in 'adjusted' (or 'real') PWV.

Carotid-to-radial pulse wave velocity (PWVcr) has been proposed to evaluate endothelial function. However, the measurement ofPWVcris not without limitations. A new simple approach could have wide application.Stiffness index(SI) is obtained by analysis of the peripheral pulse wave and gives reproducible information about stiffness of large arteries. This study assessed the effects of hyperemia on SI and compared it withPWVcrin 14 healthy subjects. Both were measured at rest and during 8 minutes after ischemia. SI temporal course was determined. At 1 minute, SI andPWVcrdecreased (5.58±0.24to5.34±0.23 m/s,P<0.05;7.8±1.0to7.2±0.9 m/s;P<0.05, resp.). SI was positively related toPWVcrin baseline (r=0.62,P<0.05), at 1 minute (r=0.79,P<0.05), and during the whole experimental session (r=0.52,P<0.05).Conclusion. Hyperemia significantly decreases SI in healthy subjects. SI was related toPWVcrand could be used to facilitate the evaluation of hyperemia-related changes in arterial stiffness.

This work was carried out in a Uruguayan (South American) population to characterize aging-associated physiological arterial changes. Parameters markers of subclinical atherosclerosis and that associate age-related changes were evaluated in healthy people. A conservative approach was used and people with nonphysiological and pathological conditions were excluded. Then, we excluded subjects with (a) cardiovascular (CV) symptoms, (b) CV disease, (c) diabetes mellitus or renal failure, and (d) traditional CV risk factors (other than age and gender). Subjects (n=388) were submitted to non-invasive vascular studies (gold-standard techniques), to evaluate (1) common (CCA), internal, and external carotid plaque prevalence, (2) CCA intima-media thickness and diameter, (3) CCA stiffness (percentual pulsatility, compliance, distensibility, and stiffness index), (4) aortic stiffness (carotid-femoral pulse wave velocity), and (5) peripheral and central pressure wave-derived parameters. Age groups: ≤20, 21–30, 31–40, 41–50, 51–60, 61–70, and 71–80 years old. Age-related structural and functional vascular parameters profiles were obtained and analyzed considering data from other populations. The work has the strength of being the first, in Latin America, that uses an integrative approach to characterize vascular aging-related changes. Data could be used to define vascular aging and abnormal or disease-related changes.

In this work we present an initiative to develop a national (Uruguayan) program to evaluate vascular age and to detect pre-clinical atherosclerosis using: gold-standard technologies; complimentary and integrative approaches to asses arterial functional and structural indexes; data bases systems to process, analyze and determine normal and reference values and to identify the most sensitive markers of vascular changes for different ages. We evaluated, in a Uruguayan population complementary structural and functional vascular parameters that associate aging-related changes and are considered markers of sub-clinical atherosclerosis. Traditional CV risk factors were assessed. The subjects (n=281) were submitted to non-invasive vascular studies to evaluate: 1) Common carotid artery (CCA) intima-media thickness and diameter waveforms, 2) CCA stiffness, 3) aortic stiffness (pulse wave velocity) and 4) peripheral and central pressure pulse wave derived parameters. Age groups: 21-30, 31-40, 41-50, 51-60, and 61-70 years-old. Age-related profiles were obtained for the different vascular parameters, and their utility to assess vascular changes in young, middle-aged and old subjects was evaluated. The work has the strength of being the first that uses, in Latin-America an integrative approach to characterize vascular aging-related changes.

Gender-related difference in cardiovascular diseases is one of the most investigated and still unsolved issues. Finding an explanation to this topic might have important implications for the understanding of the differences between men and women in diseases and possibly lead to the development of gender-specific strategies for its management. Recent studies have proposed that the capacitive or reservoir function of the aorta and large elastic arteries plays a major role in determining the pulse wave morphology. The pressure waveform can be explained in terms of a reservoir pressure related to arterial compliance and an "excess" or wave-related pressure associated with traveling waves. Gender-differences in the ascending aorta pressure waveform reservoir and excess components are to be characterized. The aim of this study was to evaluate, by means of a mathematical approach, gender-related differences in the central aortic pressure waveform components. Central aortic pressure waveform was non-invasively obtained in 22 healthy subjects (Age: 20 years old; 11 female). Males and females showed differences in the level and time to maximal excess pressure component, but no gender-related differences were found in the reservoir one.

Study of humans aging has presented difficulties in separating the aging process from concomitant disease and/or in defining normality and abnormality during its development. In accordance with this, aging associates structural and functional changes evidenced in variations in vascular parameters witch suffer alterations during atherosclerosis and have been proposed as early markers of the disease. The absence of adequate tools to differentiate the expected (normal) vascular changes due to aging from those related with a vascular disease is not a minor issue. For an individual, an early diagnosis of a vascular disease should be as important as the diagnosis of a healthy vascular aging. Recent studies have proposed that the capacitive or reservoir function of the aorta and large elastic arteries plays a major role in determining the pulse wave morphology. The arterial pressure waveform can be explained in terms of a reservoir pressure, related to the arterial system compliance, and an "excess" or wave-related pressure, associated with the traveling waves. The aim of this study was to evaluate, by means of a mathematical approach, age-related changes in measured, reservoir and excess central aortic pressure in order to determine if age-related changes are concentrated in particular decades of life. Central aortic pressure waveform was non-invasively obtained in healthy subjects (age range: 20-69 years old). Age-related profiles in measured, reservoir and excess pressure were calculated.