46 resultados para Vascular Stiffness
em BORIS: Bern Open Repository and Information System - Berna - Suiça
Resumo:
Many aspects of hypertension diagnosis and treatment are similar in young and old patients. However, some differences exist. Due to the increasing vascular stiffness most elderly patients have isolated systolic hypertension and its prevalence in the population is high. Blood pressure should be measured in the sitting position and also with the patient standing to exclude orthostatic hypotension, a frequent problem in elderly patients. Pseudohypertension, a source of inadequate measurements in elderly patients, should be recognized. In comparison to other health problems there is good scientific evidence for antihypertensive treatment in elderly patients. As treatment does not only improve survival, but also reduces cardiovascular events such as non-fatal stroke or myocardial infarction, antihypertensive therapy is an important measure to prevent functional decline and disability.
Resumo:
OBJECTIVE Renal resistive index (RRI) varies directly with renal vascular stiffness and pulse pressure. RRI correlates positively with arteriolosclerosis in damaged kidneys and predicts progressive renal dysfunction. Matrix Gla-protein (MGP) is a vascular calcification inhibitor that needs vitamin K to be activated. Inactive MGP, known as desphospho-uncarboxylated MGP (dp-ucMGP), can be measured in plasma and has been associated with various cardiovascular (CV) markers, CV outcomes and mortality. In this study we hypothesize that increased RRI is associated with high levels of dp-ucMGP. DESIGN AND METHOD We recruited participants via a multi-center family-based cross-sectional study in Switzerland exploring the role of genes and kidney hemodynamics in blood pressure regulation. Dp-ucMGP was quantified in plasma samples by sandwich ELISA. Renal doppler sonography was performed using a standardized protocol to measure RRIs on 3 segmental arteries in each kidney. The mean of the 6 measures was reported. Multiple regression analysis was performed to estimate associations between RRI and dp-ucMGP adjusting for sex, age, pulse pressure, mean pressure, renal function and other CV risk factors. RESULTS We included 1035 participants in our analyses. Mean values were 0.64 ± 0.06 for RRI and 0.44 ± 0.21 (nmol/L) for dp-ucMGP. RRI was positively associated with dp-ucMGP both before and after adjustment for sex, age, body mass index, pulse pressure, mean pressure, heart rate, renal function, low and high density lipoprotein, smoking status, diabetes, blood pressure and cholesterol lowering drugs, and history of CV disease (P < 0.001). CONCLUSIONS RRI is independently and positively associated with high levels of dp-ucMGP after adjustment for pulse pressure and common CV risk factors. Further studies are needed to determine if vitamin K supplementation can have a positive effect on renal vascular stiffness and kidney function.
Resumo:
The vitamin D(3) and nicotine (VDN) model is a model of isolated systolic hypertension (ISH) due to arterial calcification raising arterial stiffness and vascular impedance similar to an aged and stiffened arterial tree. We therefore analyzed the impact of this aging model on normal and diseased hearts with myocardial infarction (MI). Wistar rats were treated with VDN (n = 9), subjected to MI by coronary ligation (n = 10), or subjected to a combination of both MI and VDN treatment (VDN/MI, n = 14). A sham-treated group served as control (Ctrl, n = 10). Transthoracic echocardiography was performed every 2 wk, whereas invasive indexes were obtained at week 8 before death. Calcium, collagen, and protein contents were measured in the heart and the aorta. Systolic blood pressure, pulse pressure, thoracic aortic calcium, and end-systolic elastance as an index of myocardial contractility were highest in the aging model group compared with MI and Ctrl groups (P(VDN) < 0.05, 2-way ANOVA). Left ventricular wall stress and brain natriuretic peptide (P(VDNxMI) = not significant) were highest, while ejection fraction, stroke volume, and cardiac output were lowest in the combined group versus all other groups (P(VDNxMI) < 0.05). The combination of ISH due to this aging model and MI demonstrates significant alterations in cardiac function. This model mimics several clinical phenomena of cardiovascular aging and may thus serve to further study novel therapies.
Resumo:
In adults the contour analysis of peripheral pressure waves in the upper limb reflects central aortic stiffness. Here, we wanted to demonstrate the appropriateness of pulse contour analysis to assess large artery stiffness in children. Digital volume pulse analysis, with the computation of the stiffness index and pulse wave velocity between carotid and femoral artery, were simultaneously determined in 79 healthy children between 8 years and 15 years (mean age 11.4 years, 32 girls). The stiffness index of 42 healthy adults (mean age 45.6 years, 26 women) served as control. Pulse wave velocity between carotid and femoral artery was directly correlated with systolic pressure and mean blood pressure, as well as with pulse pressure. The results from the stiffness index of children revealed the expected values extrapolated from the linear regression of adulthood stiffness index vs. age. Childhood stiffness index positively correlated with pulse wave velocity (r(2) = 0.07, P = 0.02) but not with blood pressure parameters. The exclusion of individuals with an increased vascular tone, as indicated by a reflexion index > 90%, improved the correlation between stiffness index and pulse wave velocity (r(2) = 0.13, P = 0.001). Our data indicate that digital volume pulse-based analysis has limitations if compared with pulse wave velocity to measure arterial stiffness, mostly in patients with a high vascular tone.
Resumo:
Children conceived by assisted reproductive technologies (ART) display a level of vascular dysfunction similar to that seen in children of mothers with preeclamspia. The long-term consequences of ART-associated vascular disorders are unknown and difficult to investigate in healthy children. Here, we found that vasculature from mice generated by ART display endothelial dysfunction and increased stiffness, which translated into arterial hypertension in vivo. Progeny of male ART mice also exhibited vascular dysfunction, suggesting underlying epigenetic modifications. ART mice had altered methylation at the promoter of the gene encoding eNOS in the aorta, which correlated with decreased vascular eNOS expression and NO synthesis. Administration of a deacetylase inhibitor to ART mice normalized vascular gene methylation and function and resulted in progeny without vascular dysfunction. The induction of ART-associated vascular and epigenetic alterations appeared to be related to the embryo environment; these alterations were possibly facilitated by the hormonally stimulated ovulation accompanying ART. Finally, ART mice challenged with a high-fat diet had roughly a 25% shorter life span compared with control animals. This study highlights the potential of ART to induce vascular dysfunction and shorten life span and suggests that epigenetic alterations contribute to these problems.
Resumo:
BACKGROUND Acute exposure to high altitude stimulates free radical formation in lowlanders, yet whether this persists during chronic exposure in healthy, well-adapted and maladapted highlanders suffering from chronic mountain sickness (CMS) remains to be established. METHODS Oxidative-nitrosative stress (as determined by the presence of the biomarkers ascorbate radical [A •- ], via electron paramagnetic resonance spectroscopy, and nitrite [NO 2 2 ], via ozone-based chemiluminescence) was assessed in venous blood of 25 male highlanders in Bolivia living at 3,600 m with CMS (n 5 13, CMS 1 ) and without CMS (n 5 12, CMS 2 ). Twelve age- and activity-matched, healthy, male lowlanders were examined at sea level and during acute hypoxia. We also measured fl ow-mediated dilatation (FMD), arterial stiffness defined by augmentation index normalized for a heart rate of 75 beats/min (AIx-75), and carotid intima-media thickness (IMT). RESULTS Compared with normoxic lowlanders, oxidative-nitrosative stress was moderately increased in the CMS 2 group ( P , .05), as indicated by elevated A •- (3,191 457 arbitrary units [AU] vs 2,640 445 AU) and lower NO 2 2 (206 55 nM vs 420 128 nM), whereas vascular function remained preserved. This was comparable to that observed during acute hypoxia in lowlanders in whom vascular dysfunction is typically observed. In contrast, this response was markedly exaggerated in CMS 1 group (A •- , 3,765 429 AU; NO 2 2 , 148 50 nM) compared with both the CMS 2 group and lowlanders ( P , .05). This was associated with systemic vascular dysfunction as indicated by lower ( P , .05 vs CMS 2 ) FMD (4.2% 0.7% vs 7.6% 1.7%) and increased AIx-75 (23% 8% vs 12% 7%) and carotid IMT (714 127 m M vs 588 94 m M). CONCLUSIONS Healthy highlanders display a moderate, sustained elevation in oxidative-nitrosative stress that, unlike the equivalent increase evoked by acute hypoxia in healthy lowlanders, failed to affect vascular function. Its more marked elevation in patients with CMS may contribute to systemic vascular dysfunction.
Inactive Matrix Gla-Protein Is Associated With Arterial Stiffness in an Adult Population-Based Study
Resumo:
Increased pulse wave velocity (PWV) is a marker of aortic stiffness and an independent predictor of mortality. Matrix Gla-protein (MGP) is a vascular calcification inhibitor that needs vitamin K to be activated. Inactive MGP, known as desphospho-uncarboxylated MGP (dp-ucMGP), can be measured in plasma and has been associated with various cardiovascular markers, cardiovascular outcomes, and mortality. In this study, we hypothesized that high levels of dp-ucMGP are associated with increased PWV. We recruited participants via a multicenter family-based cross-sectional study in Switzerland. Dp-ucMGP was quantified in plasma by sandwich ELISA. Aortic PWV was determined by applanation tonometry using carotid and femoral pulse waveforms. Multiple regression analysis was performed to estimate associations between PWV and dp-ucMGP adjusting for age, renal function, and other cardiovascular risk factors. We included 1001 participants in our analyses (475 men and 526 women). Mean values were 7.87±2.10 m/s for PWV and 0.43±0.20 nmol/L for dp-ucMGP. PWV was positively associated with dp-ucMGP both before and after adjustment for sex, age, body mass index, height, systolic and diastolic blood pressure (BP), heart rate, renal function, low- and high-density lipoprotein, glucose, smoking status, diabetes mellitus, BP and cholesterol lowering drugs, and history of cardiovascular disease (P≤0.01). In conclusion, high levels of dp-ucMGP are independently and positively associated with arterial stiffness after adjustment for common cardiovascular risk factors, renal function, and age. Experimental studies are needed to determine whether vitamin K supplementation slows arterial stiffening by increasing MGP carboxylation.
Resumo:
Our previous data suggested that angiopoietin-2 (Ang-2) is linked to pericyte loss, thereby playing an important role in diabetic retinopathy. In this study, we investigated the effect of retinal overexpression of human Ang-2 (mOpsinhAng2 mouse) on vascular morphology in non-diabetic and streptozotozin-induced diabetic animals. Pericyte (PC) coverage and acellular capillary (AC) formation were quantitated in retinal digest preparations after 3 and 6 months of diabetes duration. The degree of retinopathy in non-diabetic mOpsinhAng2 mice at 3 months (-21% PC, +49% AC) was comparable to age-matched diabetic wild type mice. Diabetic mOpsinhAng2 mice exhibited significantly worse vascular pathology than wild type counterparts at 6 months. Quantitative PCR revealed that human Ang-2 mRNA was highly overexpressed in retinas of transgenic mice. Our data demonstrate that overexpression of Ang-2 in the retina enhances vascular pathology, indicating that Ang-2 plays an essential role in diabetic vasoregression via destabilization of pericytes.
Resumo:
In addition to the increasingly significant role of multislice computed tomography in forensic pathology, the performance of whole-body computed tomography angiography provides outstanding results. In this case, we were able to detect multiple injuries of the parenchymal organs in the upper abdomen as well as lesions of the brain parenchyma and vasculature of the neck. The radiologic findings showed complete concordance with the autopsy and even supplemented the autopsy findings in areas that are difficult to access via a manual dissection (such as the vasculature of the neck). This case shows how minimally invasive computed tomography angiography can serve as an invaluable adjunct to the classic autopsy procedure.
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The latest-generation Amplatzer vascular plug (AVP), the AVP 4, is designed for embolization of smaller vessels without a sheath or guiding catheter. This study evaluated the AVP 4 in peripheral vascular embolization.
Resumo:
To report the use of the second-generation Amplatzer Vascular Plug II (AVP II) for the treatment of a posttraumatic type A carotid-cavernous fistula (CCF).
Resumo:
Delayed occlusion time in parent artery occlusion of brain-supplying vessels might carry risk for thromboembolic complications. Vascular plug devices are successfully used in cardiopulmonary and peripheral interventions to occlude high-flow lesions and have been adapted for use in neurointerventions. The purpose of the present study was to experimentally evaluate the immediate occlusion time of the AMPLATZER vascular plug (AVP) II-a second-generation cylindrical, self-expandable, resheathable nitinol wire mesh consisting of three lobes-in the carotid artery.
Resumo:
BACKGROUND: Peripheral artery disease (PAD) is common and imposes a high risk of major systemic and limb ischemic events. The REduction of Atherothrombosis for Continued Health (REACH) Registry is an international prospective registry of patients at risk of atherothrombosis caused by established arterial disease or the presence of 3 atherothrombotic risk factors. METHODS AND RESULTS: We compared the 2-year rates of vascular-related hospitalizations and associated costs in US patients with established PAD across patient subgroups. Symptomatic PAD at enrollment was identified on the basis of current intermittent claudication with an ankle-brachial index (ABI) <0.90 or a history of lower-limb revascularization or amputation. Asymptomatic PAD was diagnosed on the basis of an enrollment ABI <0.90 in the absence of symptoms. Overall, 25 763 of the total 68 236-patient REACH cohort were enrolled from US sites; 2396 (9.3%) had symptomatic and 213 (0.8%) had asymptomatic PAD at baseline. One- and cumulative 2-year follow-up data were available for 2137 (82%) and 1677 (64%) of US REACH patients with either symptomatic or asymptomatic PAD, respectively. At 2 years, mean cumulative hospitalization costs, per patient, were $7445, $7000, $10 430, and $11 693 for patients with asymptomatic PAD, a history of claudication, lower-limb amputation, and revascularization, respectively (P=0.007). A history of peripheral intervention (lower-limb revascularization or amputation) was associated with higher rates of subsequent procedures at both 1 and 2 years. CONCLUSIONS: The economic burden of PAD is high. Recurring hospitalizations and repeat revascularization procedures suggest that neither patients, physicians, nor healthcare systems should assume that a first admission for a lower-extremity PAD procedure serves as a permanent resolution of this costly and debilitating condition.
Resumo:
The acetabular labrum plays an important role in hip joint stability and protection of the articular cartilage of the hip. Despite this, few investigators have evaluated its microscopic vasculature and, to our knowledge, none has assessed its macroscopic blood supply. The purposes of this study were to identify the origin and course of the vascular supply to the acetabular labrum to determine if this blood supply is affected by a labral tear.
Resumo:
Intra-organ and intra-vascular pressures can be used to estimate intra-abdominal pressure. The aim of this prospective, interventional study was to assess the effect of PEEP on the accuracy of pressure estimation at different measurement sites in a model of increased abdominal pressure.