the clinical significance and application of vascular stiffness measurements

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Modifications des propriétés structurelles et fonctionnelles des gros troncs artériels dans l'insuffisance rénale (valeur pronostique et évolution après transplantation)

La maladie rénale chronique (MRC) est caractérisée par une fréquence élevée de complications cardiovasculaires (CV). La rigidité artérielle est un marqueur de la maladie CV, corrélé avec la morbi-mortalité des patients en dialyse chronique. Notre équipe a déjà observé que des modifications structurelles et fonctionnelles des gros troncs artériels apparaissent néanmoins dès les stades précoces de la MRC.Le suivi prospectif d une large cohorte de patients insuffisants rénaux non dialysés, nous a permis de démontrer que le remodelage artériel s accentue avec la progression de la MRC, avec notamment une augmentation de la rigidité carotidienne, une diminution de l épaisseur intima-média, une augmentation du diamètre interne de la carotide et du stress circomférentiel. Notre étude prospective a permis de montrer que le stress circonférentiel est prédictif de la vitesse de dégradation de la fonction rénale, même après ajustement sur les autres facteurs de risque CV et de progression de la MRC. Nous avons également étudié la morbi-mortalité globale et CV en fonction des paramètres artériels mesurés lors de l inclusion. Après analyse multivariée, il apparaît que la rigidité aortique est corrélée au risque de décès ou de survenue d un événement CV, alors que le diamètre interne de la carotide est associé à la mortalité globale, même après ajustement sur les facteurs CV classiques. La transplantation rénale permet une amélioration du pronostic CV des patients insuffisants rénaux. Nos études, réalisées sur 2 cohortes prospectives de patients transplantés rénaux ont permis d objectiver une nette amélioration de la rigidité aortique dans les mois qui suivent la greffe. Nous démontrons par ailleurs que le remodelage artériel est également réversible, avec diminution du diamètre interne, augmentation de l épaisseur intima-média et correction partielle du stress circonférentiel au niveau de la carotide interne. Cette réversibilité de la rigidité est particulièrement importante chez les receveurs bénéficiant d une transplantation avec un donneur jeune, et ceci indépendamment du degré d amélioration la fonction rénale observée dans la période post-greffe.Elle est aussi beaucoup plus marquée chez les patients recevant un greffon rénal provenant d un donneur vivant.La qualité du greffon, déterminée par l âge du donneur ou son origine (donneur vivant vs donneur décédé) est donc capitale pour prédire l amélioration des paramètres artériels chez le receveur et indirectement son pronostic CV à moyen terme.Chronic Kidney Disease (CKD) is associated with frequent cardiovascular complications. Arterialstiffness is a marker of cardiovascular (CV) disease and is associated with mortality in patients with end-stagerenal disease (ESRD). Our group has previously suggested that a maladaptative arterial remodeling occurs earlyduring CKD, even in patients with mild kidney dysfunction. Our first prospective study was based on a large CKD cohort. Our data confirm that the large arteries modifications, which include increase of carotid stiffness, decrease of intima-media thickness, carotid arterydilatation with enhancement of circumferential wall stress (CWS), worsen during CKD progression. We also showthat initial CWS is associated with the rate of kidney function deterioration, even after adjustment for other CV andCKD risk factors. In addition, we found that aortic stiffness was associated with both the overall survival and therisk of cardiovascular events. The internal carotid diameter is predictive of the overall mortality, after multivariateanalysis. Kidney transplantation reduces the CV risk of ESRD patients. Our 2 prospective studies demonstratethat aortic stiffness can improve during the first year after transplantation. The maladaptative arterial remodelingcan also reverse after transplantation, with a significant reduction of the carotide diameter, an increase of theintima-media thickness and a partial correction of the CWS. The improvement of the aortic stiffness and thereversal of this maladaptative arterial remodeling is particularily important in patients receiving a kidney allograftform a young allograft donor, independently of the post-transplant renal function. The kidney recipients with aliving donor experience a major improvement of their arterial parameters when compared with recipients withdeceased donors, and this difference remains significant after adjustment for other confounding factors. Inconclusion, the quality of the kidney allograft (age and source) may play an important role in the cardiovascularoutcome of the recipient. This advantage could be mediated a beneficial effect of transplantation on centralarteries structure and function.PARIS5-Bibliotheque electronique (751069902) / SudocPARIS-BIUM-Bib. électronique (751069903) / SudocSudocFranceF

Early Vascular Ageing (EVA): Definitions and Clinical Applicability.

Arterial stiffness has been accumulating evidence as an intermediate cardiovascular endpoint. It has been established as an independent risk marker for cardiovascular disease, and reflects the dissociation between chronologic and biologic age of large arteries-attributing earlier the risk that a normal vascular ageing process had installed to occur several years later. The concept of Early Vascular Ageing (EVA) is developed to establish primordial prevention, identifying individuals whose ageing path has been accelerated either by inherent features, interaction with the environment or arterial exposure to several types of insults that evolve to medial layer morphological changes. Understanding the pathophysiology of vascular ageing, its consequences and therapeutic opportunities is therefore an advantage that could be translated in time of prevention and survival free of cardiovascular disease. As the EVA construct is advancing, new features appear as interesting to better translate it into clinical practice.(undefined)info:eu-repo/semantics/publishedVersio

Modélisation du comportement mécanique d’artères carotides communes humaines in vivo

A partir de mesures non invasives cliniques sur des sujets humains, nous proposons un nouveau modèle de comportement mécanique 3D d'artères carotides communes qui tient compte du caractère hyperélastique, composite, actif, précontraint et dynamique du tissu biologique. Le problème aux limites est résolu par une méthode semi-analytique, ce qui permet d’obtenir une évaluation des cinématiques de déformation et des distributions de contraintes pariétales de la structure artérielle in vivo au cours d’un cycle cardiaque

Pulse wave velocity distribution in a cohort study: from arterial stiffness to early vascular aging

BACKGROUND: By contrast with other southern European people, north Portuguese population registers an especially high prevalence of hypertension and stroke incidence. We designed a cohort study to identify individuals presenting accelerated and premature arterial aging in the Portuguese population. METHOD: Pulse wave velocity (PWV) was measured in randomly sampled population dwellers aged 18-96 years from northern Portugal, and used as a marker of early vascular aging (EVA). Of the 3038 individuals enrolled, 2542 completed the evaluation. RESULTS: Mean PWV value for the entire population was 8.4?m/s (men: 8.6?m/s; women: 8.2?m/s; P??10?m/s). Logistic regression models indicated gender differences concerning the risk of developing large artery damage, with women having the same odds of PWV above 10?m/s 10 years later than men. CONCLUSION: The population PWV values were higher than expected in a low cardiovascular risk area (Portugal). High prevalence rates of EVA and noteworthy large artery damage in young ages were found.Funded by the Life and Health Research Institute, Minho University, Guimarães, Portugal

Measuring aortic distensibility with cmr using central pressures estimated in the magnet: comparison with carotid and peripheral pressures

International audienc

0272: True antihypertensive efficacy of sequential nephron blockade in patients with resistant hypertension and confirmed medication adherence

ObjectiveWe previously showed (Bobrie et al. J Hypertens 2012) that sequential-nephron blockade (SNB) was more effective than combined renin angiotensin system blockade (RB) for controlling BP in patients with resistant hypertension (RH). In this post-hoc analysis, we assessed medication adherence (MA) and its influence on the antihypertensive response to SNB/RB with a new combined scoring system.Design and MethodPts with daytime ambulatory SBP/DBP (dASBP/dADBP) >135 and/or 85mmHg, despite 4 week-treatment with irbesartan 300mg+HCTZ 12.5mg+amlodipine 5mg, were randomised either to SNB (i.e.+spironolactone 25mg, then +furosemide 20-40mg, then +amiloride 5mg, n=82) or RB (ramipril 5-10mg, then bisoprolol 5-10mg, RB group, n=82) for 12 weeks. MA was scored according to 4 criteria: (i) trough/peak plasma irbesartan (Irb) concentration (HPLC); (ii) urinary AcSDKP/creatinine ratio (UR) to evaluate ramipril intake; (iii) delay of last medication intake before visit (LMI); and (iv) pill counting (PC, %). One point of MA score was attributed to trough Irb >20ng/ml, UR >4nmol/mmol, LMI <24h and PC >80%. MA was defined as low (LMA, score <2), intermediate (IMA, score=3), and optimal (OMA, score=4).Results82 pts among 164 had OMA (46 SNB and 36 RB); 52 pts had IMA (23 SNB and 29 RB); and 30 pts had LMA (13 SNB and 17 RB) (inter-groups difference: NS). LMA pts were younger than SMA pts (50±11 vs. 56±10 yrs, p<0.011). In OMA pts, the difference in dASBP/dADBP between SNB vs RB was significant (–11 [–17;–6]/–6 [–9;–2] mmHg, p<0.0001/p=0.0025), favoring SNB, whereas in LMA pts the significant difference between the two groups was no more observed (–6 [–19;7]/–1 [–10;7] mmHg, p=0.352/p=0.7096).ConclusionThe major BP lowering effect of SNB vs. RB observed in pts with OMA is lost in pts LMA. Combined methods for assessing MA allow determining the true efficacy of antihypertensive strategies in patients with RH. Reinforcement of MA in RH pts is deemed necessary