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Sample records for ambulatory arterial stiffness

  1. Reproducibility of the ambulatory arterial stiffness index in hypertensive patients

    DEFF Research Database (Denmark)

    Dechering, D.G.; Steen, M.S. van der; Adiyaman, A.;

    2008-01-01

    BACKGROUND: We studied the repeatability of the ambulatory arterial stiffness index (AASI), which can be computed from 24-h blood pressure (BP) recordings as unity minus the regression slope of diastolic on systolic BP. METHODS: One hundred and fifty-two hypertensive outpatients recruited...

  2. Determinants of the ambulatory arterial stiffness index in 7604 subjects from 6 populations

    DEFF Research Database (Denmark)

    Adiyaman, Ahmet; Dechering, Dirk G; Boggia, José

    2008-01-01

    The ambulatory arterial stiffness index (AASI) is derived from 24-hour ambulatory blood pressure recordings. We investigated whether the goodness-of-fit of the AASI regression line in individual subjects (r(2)) impacts on the association of AASI with established determinants of the relation between...

  3. Association between endothelial dysfunction and arterial stiffness in continuous ambulatory peritoneal dialysis patients

    Institute of Scientific and Technical Information of China (English)

    顾玥

    2014-01-01

    Objective To investigate the association between endothelial dysfunction and arterial stiffness in continuous ambulatory peritoneal dialysis(CAPD)patients.Methods Ninety-four stable CAPD patients from a single center were enrolled in this cross-sectional study.Ultrasound evaluation was conducted on brachial artery to estimate endothelial-dependent

  4. Ambulatory arterial stiffness indices and target organ damage in hypertension

    Directory of Open Access Journals (Sweden)

    Gómez-Marcos Manuel

    2012-01-01

    Full Text Available Abstract Background The present study was designed to evaluate which arterial stiffness parameter - AASI or the home arterial stiffness index (HASI - correlates best with vascular, cardiac and renal damage in hypertensive individuals. Methods A cross-sectional study was carried out involving 258 hypertensive patients. AASI and HASI were defined as the 1-regression slope of diastolic over systolic blood pressure readings obtained from 24-hour recordings and home blood pressure over 6 days. Renal damage was evaluated by glomerular filtration rate (GFR and microalbuminuria; vascular damage by carotid intima-media thickness (IMT, pulse wave velocity (PWV and ankle/brachial index (ABI; and left ventricular hypertrophy by the Cornell voltage-duration product (VDP and the Novacode index. Results AASI and HASI were not correlated with microalbuminuria, however AASI and HASI- blood pressure variability ratio (BPVR showed negative correlation with GRF. The Cornell PDV was positively correlated with AASI- BPVR-Sleep (r = 0.15, p Conclusions After adjusting for age, gender and 24-hour heart, the variables that best associated with the variability of IMT, PWV and ABI were AASI and Awake-AASI, and with GFR was HASI-BPVR.

  5. Need for insulin to control gestational diabetes is reflected in the ambulatory arterial stiffness index

    Directory of Open Access Journals (Sweden)

    Kärkkäinen Henna

    2013-01-01

    Full Text Available Abstract Background The aim was to evaluate the metabolic profile in conjunction with vascular function using the ambulatory arterial stiffness index (AASI in women with uncomplicated pregnancies and in women with gestational diabetes mellitus (GDM. Methods Plasma glucose, lipids, HOMA –IR (homeostasis model assessment of insulin resistance and AASI, as obtained from 24-hour ambulatory blood pressure monitoring in third trimester pregnancy and at three months postpartum, were measured in three groups of women: controls (N = 32, women with GDM on diet (N = 42 and women with GDM requiring insulin treatment (N = 10. Results Women with GDM had poorer glycemic control and higher HOMA-IR during and after pregnancy and their total and LDL (low density lipoprotein cholesterol levels were significantly higher after pregnancy than in the controls. After delivery, there was an improvement in AASI from 0.26 ± 0.10 to 0.17 ± 0.09 (P = 0.002 in women with GDM on diet, but not in women with GDM receiving insulin whose AASI tended to worsen after delivery from 0.30 ± 0.23 to 0.33 ± 0.09 (NS, then being significantly higher than in the other groups (P = 0.001-0.047. Conclusions Women with GDM had more unfavorable lipid profile and higher blood glucose values at three months after delivery, the metabolic profile being worst in women requiring insulin. Interestingly, the metabolic disturbances at three months postpartum were accompanied by a tendency towards arterial stiffness to increase in women requiring insulin.

  6. Vascular Health Assessment of The Hypertensive Patients (VASOTENS) Registry: Study Protocol of an International, Web-Based Telemonitoring Registry for Ambulatory Blood Pressure and Arterial Stiffness

    Science.gov (United States)

    Parati, Gianfranco; Avolio, Alberto; Rogoza, Anatoly N; Kotovskaya, Yulia V; Mulè, Giuseppe; Muiesan, Maria Lorenza; Orlova, Iana A; Grigoricheva, Elena A; Cardona Muñoz, Ernesto; Zelveian, Parounak H; Pereira, Telmo; Peixoto Maldonado, João Manuel

    2016-01-01

    Background Hypertension guidelines recommend ambulatory blood pressure (ABP), central aortic pressure (CAP), and pulse wave velocity (PWV) as parameters for estimating blood pressure (BP) control and vascular impairment. Recent advances in technology have enabled devices to combine non-invasive estimation of these parameters over the 24-hour ABP monitoring. However, currently there is limited evidence on the usefulness of such an approach for routine hypertension management. Objective We recently launched an investigator-initiated, international, multicenter, observational, prospective study, the Vascular health Assessment Of The Hypertensive patients (VASOTENS) Registry, aimed at (1) evaluating non-invasive 24-hour ABP and arterial stiffness estimates (through 24-hour pulse wave analysis, PWA) in hypertensive subjects undergoing ambulatory blood pressure monitoring (ABPM) for clinical reasons; (2) assessing the changes in estimates following treatment; (3) weighing the impact of 24-hour PWA on target organ damage and cardiovascular prognosis; (4) assessing the relationship between arterial stiffness, BP absolute mean level and variability, and prognosis; and (5) validating the use of a 24-hour PWA electronic health (e-health) solution for hypertension screening. Methods Approximately 2000 subjects, referred to 20 hypertension clinics for routine diagnostic evaluation and follow-up of hypertension of any severity or stage, will be recruited. Data collection will include ABPM, performed with a device allowing simultaneous non-invasive assessment of 24-hour CAP and arterial stiffness (BPLab), and clinical data (including cardiovascular outcomes). As recommended by current guidelines, each patient will be followed-up with visits occurring at regular intervals (ideally every 6 months, and not less than once a year depending on disease severity). A Web-based telemedicine platform (THOLOMEUS) will be used for data collection. The use of the telemedicine system will allow

  7. Pharmacological modulation of arterial stiffness.

    LENUS (Irish Health Repository)

    Boutouyrie, Pierre

    2011-09-10

    Arterial stiffness has emerged as an important marker of cardiovascular risk in various populations and reflects the cumulative effect of cardiovascular risk factors on large arteries, which in turn is modulated by genetic background. Arterial stiffness is determined by the composition of the arterial wall and the arrangement of these components, and can be studied in humans non-invasively. Age and distending pressure are two major factors influencing large artery stiffness. Change in arterial stiffness with drugs is an important endpoint in clinical trials, although evidence for arterial stiffness as a therapeutic target still needs to be confirmed. Drugs that independently affect arterial stiffness include antihypertensive drugs, mostly blockers of the renin-angiotensin-aldosterone system, hormone replacement therapy and some antidiabetic drugs such as glitazones. While the quest continues for \\'de-stiffening drugs\\

  8. Arterial Stiffness: Recommendations and Standardization

    Science.gov (United States)

    Townsend, Raymond R.

    2017-01-01

    The use of arterial stiffness measurements in longitudinal cohorts of normal populations, hypertensive patients, diabetic patients, healthy elderly, and patients on hemodialysis have confirmed the value of this important measure of arterial health, and established its complementary role to measures of blood pressure. Its contribution to understanding cardiovascular and mortality risk beyond blood pressure measurements has moved measures of arterial stiffness into the ranks of factors such as elevated cholesterol, diabetes, and left ventricular hypertrophy in considering cardiovascular risk. The recent international collaboration's publication of reference ranges for normal people and those with hypertension, along with the American Heart Association's recent scientific statement on standardizing arterial stiffness measurements are important aspects to consider in future studies employing these valuable methods, particularly as interventions that not only lower blood pressure but improve arterial function are tested in the clinical arena. PMID:28275588

  9. Arterial Stiffness and Dialysis Calcium Concentration

    Directory of Open Access Journals (Sweden)

    Fabrice Mac-Way

    2011-01-01

    Full Text Available Arterial stiffness is the major determinant of isolated systolic hypertension and increased pulse pressure. Aortic stiffness is also associated with increased cardiovascular morbidity and mortality in patients with chronic kidney disease, hypertension, and general population. Hemodynamically, arterial stiffness results in earlier aortic pulse wave reflection leading to increased cardiac workload and decreased myocardial perfusion. Although the clinical consequence of aortic stiffness has been clearly established, its pathophysiology in various clinical conditions still remains poorly understood. The aim of the present paper is to review the studies that have looked at the impact of dialysis calcium concentration on arterial stiffness. Overall, the results of small short-term studies suggest that higher dialysis calcium is associated with a transient but significant increase in arterial stiffness. This calcium dependant increase in arterial stiffness is potentially explained by increased vascular smooth muscle tone of the conduit arteries and is not solely explained by changes in mean blood pressure. However, the optimal DCa remains to be determined, and long term studies are required to evaluate its impact on the progression of arterial stiffness.

  10. Genetic determinants of arterial stiffness: Results from the Rotterdam Study

    NARCIS (Netherlands)

    M.P.S. Sie (Mark)

    2007-01-01

    textabstractArterial stiffness increases with age. It is also associated with various diseases, such as diabetes mellitus and hypertension. Recently, arterial stiffness has also been found to independently predict cardiovascular disease. The pathogenesis of arterial stiffness, however, has n

  11. Association of microalbuminuria with ambulatory arterial stiffness index in patients with hypertension%动态动脉硬化指数与高血压患者微量白蛋白尿的关系

    Institute of Scientific and Technical Information of China (English)

    王雅琼; 胡亚蓉; 李燕; 李华; 初少莉; 朱鼎良; 高平进

    2011-01-01

    Objective To investigate the association of microalbuminuria (MAU) with 24-hour, daytime and nighttime ambulatory arterial stiffness index (AASI) in hypertensive inpatients. Methods A total of 444 hypertensive inpatients were included in the study. AASI was defined as one minus the regression slope of diastolic on systolic blood pressure obtained from individual 24-hour blood pressure readings. MAU was d efined as urinary albumincreatinine ratio (ACR) of at least 22 mg/g creatinine in males or of 31 mg/g in females. The subjects were divided into four groups according to 24-hour AASI in quartile: AASI<0.34, 0. 34≤AASI<0. 44, 0. 44≤AASI<0. 54 and AASI≥0. 54 group. The differences between the four groups were compared. The association of MAU with 24-hour, daytime and nighttime AASI were analyzed. Results With the AASI increased, the patients had higher urinary ACR and the prevalence of MAU [8. 1 ( 5.5- 16.6 ), 10. 4 ( 6.7 - 25.4) , 12.8 ( 7.3 - 31.5 ), 16. 3 ( 8.5 45. 2); 14. 3 %, 24. 5%, 30. 6 %, 37. 8 %; both P<0.01]. 24-hour AASI, daytime AASI and nighttime AASI in MAU group were significantly higher than those in normoalbuminuria (N-MAU) group (0. 48 vs 0. 42, P<0.01;0. 51 vs 0. 46, P<0. 01; 0. 44 vs 0. 40, P<0. 05). In unadjusted analyses, 24-hour AASI, daytime and nighttime AASI correlated with ACR (β=0. 216, 0. 172, 0. 150, all P<0. 01 ). Only 24-hour AASI(P=0. 014), rather than daytime ( P= 0. 107 ) nor nighttime ( P = 0. 215 ) AASI, was independently associated with ACR by multiple linear regression after adjusting for confounders. The risk of MAU incidence added by 33. 7% for every increase of 24hour AASI by one standard deviation ( i. e. 0. 14 unit) (P=0. 048 ). Conclusion As a new index of arterial stiffness,24-hour AASI, not daytime and nighttime AASI, was associated with ACR and could independently predict MAU.%目的 探讨住院高血压患者24 h,白天和夜间的动态动脉硬化指数(AASI)与微

  12. Reference values for local arterial stiffness. Part B : femoral artery

    NARCIS (Netherlands)

    Bossuyt, Jelle; Engelen, Lian; Ferreira, Isabel; Stehouwer, Coen D; Boutouyrie, Pierre; Laurent, Stéphane; Segers, Patrick; Reesink, Koen; Van Bortel, Luc M

    2015-01-01

    OBJECTIVE: Carotid-femoral pulse wave velocity (PWV) is considered the gold standard measure of arterial stiffness, representing mainly aortic stiffness. As compared with the elastic carotid and aorta, the more muscular femoral artery may be differently associated with cardiovascular risk factors (C

  13. Physical inactivity and arterial stiffness in COPD

    Directory of Open Access Journals (Sweden)

    Sievi NA

    2015-09-01

    Full Text Available Noriane A Sievi,1 Daniel Franzen,1 Malcolm Kohler,1,2 Christian F Clarenbach1 1Division of Pulmonology, University Hospital of Zurich, 2Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland Background: Arterial stiffness is an important predictor of cardiovascular risk besides classic cardiovascular risk factors. Previous studies showed that arterial stiffness is increased in patients with COPD compared to healthy controls and exercise training may reduce arterial stiffness. Since physical inactivity is frequently observed in patients with COPD and exercise training may improve arterial stiffness, we hypothesized that low daily physical activity may be associated with increased arterial stiffness. Methods: In 123 patients with COPD (72% men; mean [standard deviation] age: 62 [7.5] years; median [quartile] forced expiratory volume in 1 second 35 [27/65] %predicted, arterial stiffness was assessed by augmentation index (AI. Daily physical activity level (PAL was measured by an activity monitor (SenseWear Pro™ >1 week. The association between AI and PAL was investigated by univariate and multivariate regression analysis, taking into account disease-specific characteristics and comorbidities. Results: Patients suffered from moderate (35%, severe (32%, and very severe (33% COPD, and 22% were active smokers. Median (quartile PAL was 1.4 (1.3/1.5 and mean (standard deviation AI 26% (9.2%. PAL showed a negative association with AI (B=-9.32, P=0.017 independent of age, sex, blood pressure, and airflow limitation. Conclusion: In COPD patients, a higher PAL seems to favorably influence arterial stiffness and therefore may reduce cardiovascular risk. Clinical Trial Registration: www.ClinicalTrials.gov, NCT01527773 Keywords: activity monitor, airflow limitation, COPD, physical activity level

  14. Cocoa intake and arterial stiffness in subjects with cardiovascular risk factors

    Directory of Open Access Journals (Sweden)

    Recio-Rodríguez José

    2012-02-01

    Full Text Available Abstract Background To analyze the relationship of cocoa intake to central and peripheral blood pressure, arterial stiffness, and carotid intima-media thickness in subjects with some cardiovascular risk factor. Findings Design: A cross-sectional study of 351 subjects (mean age 54.76 years, 62.4% males. Measurements: Intake of cocoa and other foods using a food frequency questionnaire, central and peripheral (ambulatory and office blood pressure, central and peripheral augmentation index, pulse wave velocity, ambulatory arterial stiffness index, carotid intima-media thickness, and ankle-brachial index. Results: Higher pulse wave velocity and greater cardiovascular risk were found in non-cocoa consumers as compared to high consumers (p Conclusions In subjects with some cardiovascular risk factors, cocoa consumption does not imply improvement in the arterial stiffness values. Trial Registration Clinical Trials.gov Identifier: NCT01325064.

  15. Red wine, arterial stiffness and central hemodynamics.

    Science.gov (United States)

    Karatzi, Kalliopi; Papaioannou, Theodore G; Papamichael, Christos; Lekakis, John; Stefanadis, Christodoulos; Zampelas, Antonis

    2009-01-01

    Red wine is considered to reduce cardiovascular risk and decrease peripheral systolic and diastolic blood pressure. Central aortic pressures are often more sensitive clinical and prognostic factors than peripheral pressures, while arterial stiffness is an independent prognostic factor for cardiovascular events. Great efforts are being made to find natural sources of improving health. In order to clarify the mechanisms under which a widely used drink, like red wine, is affecting heart and vessels, we aimed to review the available data regarding the effects of red wine on arterial stiffness, wave reflections and central blood pressures. The effect of red wine on central hemodynamics has been poorly explored with divergent results. Possible consequences of acute and long-term intake on arterial stiffness, wave reflections and central pressures are not clear. This might make someone skeptical when suggesting the consumption of a glass of red wine, although its cardioprotective actions (when moderately consumed) are already shown from epidemiological studies.

  16. Arterial stiffness as a risk factor for coronary artery disease.

    Science.gov (United States)

    Liao, Josh; Farmer, John

    2014-02-01

    Hypertension is a major modifiable risk factor, and clinical trials have demonstrated that successful reduction of elevated blood pressure to target levels translates into decreased risk for the development of coronary artery disease, stroke, heart failure, and renal failure. The arterial system had previously been regarded as a passive conduit for the transportation of arterial blood to peripheral tissues. The physiologic role the arterial system was greatly expanded by the recognition of the central role of the endothelial function in a variety of physiologic processes. The role of arterial function and structure in cardiovascular physiology was expanded with the development of a variety of parameters that evaluate arterial stiffness. Markers of arterial stiffness have been correlated with cardiovascular outcomes, and have been classified as an emerging risk factor that provides prognostic information beyond standard stratification strategies involving hypertension, diabetes, obesity, dyslipidemia and smoking. Multiple epidemiologic studies have correlated markers of arterial stiffness such as pulse-wave velocity, augmentation index and pulse pressure with risk for the development of fatal and nonfatal cardiovascular events. Additionally, measurements of arterial stiffness had clarified the results of clinical trials that demonstrated differing impacts on clinical outcomes, despite similar reductions in blood pressure, as measured by brachial and sphygmomanometry.

  17. Blood pressure and arterial stiffness in obese children and adolescents.

    Science.gov (United States)

    Hvidt, Kristian Nebelin

    2015-03-01

    Obesity, elevated blood pressure (BP) and arterial stiffness are risk factors for cardiovascular disease. A strong relationship exists between obesity and elevated BP in both children and adults. Obesity and elevated BP in childhood track into adult life increasing the risk of cardiovascular disease in adulthood. Ambulatory BP is the most precise measure to evaluate the BP burden, whereas carotid-femoral pulse wave velocity (cfPWV) is regarded as the gold standard for evaluating arterial (i.e. aortic) stiffness. These measures might contribute to a better understanding of obesity's adverse impact on the cardiovascular system, and ultimately a better prevention and treatment of childhood obesity. The overall aim of the present PhD thesis is to investigate arterial stiffness and 24-hour BP in obese children and adolescents, and evaluate whether these measures are influenced by weight reduction. The present PhD thesis is based on four scientific papers.  In a cross-sectional design, 104 severe obese children and adolescents with an age of 10-18 years were recruited when newly referred to the Children's Obesity Clinic, Holbæk University Hospital, and compared to 50 normal weighted age and gender matched control individuals. Ambulatory BP was measured, and cfPWV was investigated in two ways in respect to the distance measure of aorta; the previously recommended length - the so called subtracted distance, and the currently recommended length - the direct distance. In a longitudinal design, the obese patients were re-investigated after one-year of lifestyle intervention at the Children's Obesity Clinic in purpose of reducing the degree of obesity. In the cross-sectional design, the obese group had higher measures of obesity, while matched for age, gender and height, when compared to the control group. In the longitudinal design, 74% of the 72 followed up obese patients experienced a significant weight reduction. CfPWV was dependent on the method used to measure the

  18. Arterial stiffness: pathophysiology and clinical impact.

    Science.gov (United States)

    London, Gérard M; Marchais, Sylvain J; Guerin, Alain P; Pannier, Bruno

    2004-01-01

    The ill effects of hypertension are usually attributed to a reduction in the caliber or the number of arterioles, resulting in an increase in total peripheral resistance (TPR). This definition does not take into account the fact that BP is a cyclic phenomenon with systolic and diastolic BP being the limits of these oscillations. The appropriate term to define the arterial factor(s) opposing LV ejection is aortic input impedance which depends on TPR, arterial distensibility (D), and wave reflections (WR). D defines the capacitive properties of arterial stiffness, whose role is to dampen pressure and flow oscillations and to transform pulsatile flow and pressure in arteries into a steady flow and pressure in peripheral tissues. Stiffness is the reciprocal value of D. These parameters are BP dependent, and arteries become stiffer at high pressure. In to D which provides information about the elasticity> of artery as a hollow structure, the elastic incremental modulus (Einc) characterizes the properties of the arterial wall biomaterials, independently of vessel geometry. As an alternative, arterial D can be evaluated by measuring the pulse wave velocity (PWV) which increases with the stiffening of arteries. Arterial stiffening increases left ventricular (LV) afterload and alters the coronary perfusion. With increased PWV, the WR impacts on the aorta during systole, increasing systolic pressures and myocardial oxygen consumption, and decreasing diastolic BP and coronary flow. The arterial stiffness is altered primarily in association with increased collagen content and alterations of extracellular matrix (arteriosclerosis) as classically observed during aging or in arterial hypertension. The arterial stiffening estimated by changes in aortic PWV and intensity of WR are independent predictors of survival in end stage renal disease (ESRD) and general population. Improvement of arterial stiffening could be obtained by antihypertensive treatmen as observed with the calcium

  19. Is arterial stiffness predicted by continuous metabolic syndrome score in obese children?

    Science.gov (United States)

    Prochotska, Katarina; Kovacs, Laszlo; Vitariusova, Eva; Feber, Janusz

    2016-01-01

    The aim of the article was to evaluate arterial stiffness, an early marker of increased cardiovascular risk, in relation to obesity. The continuous metabolic syndrome (cMetS) score was calculated as sum of Z score of mean arterial pressure, body mass index, serum glucose, triglyceride, and high-density lipoprotein cholesterol in 144 obese patients and 66 nonobese controls. Ambulatory arterial stiffness index (AASI) was calculated as 1 minus regression slope of diastolic on systolic blood pressure from ambulatory blood pressure measurements. The mean AASI increased progressively with severity of obesity. The receiver operator curve analysis of body mass index and AASI showed area under the curve of 0.64 ± 0.06; cMetS area under the curve was 0.72 ± 0.05 suggesting a better predictive power of the cMetS for an increased AASI (>0.3). Patients with obesity have significantly higher arterial stiffness. A composite score such as cMetS seems to be better predictor of an increased stiffness than individual risk factors.

  20. ARTERIAL STIFFNESS AND CHRONIC KIDNEY DISEASE: CAUSES AND CONSEQUENCES

    Directory of Open Access Journals (Sweden)

    J. D. Kobalava

    2015-09-01

    Full Text Available Chronic kidney disease (CKD is associated with increased cardiovascular risk. CKD is characterized by accelerated aging of vessels in which the age-related arterial stiffness increase is exacerbated by a number of uremia-related processes. Increased arterial stiffness is associated with structural and functional disorders, as well as with the increase in cardiovascular mortality in patients with CKD. Increased arterial stiffness is diagnosed at an early stage of CKD. Modern understanding of the mechanisms of increased risk of cardiovascular complications in CKD, the factors contributing to the loss of elasticity of the arteries, arterial stiffness increase consequences are analyzed. Data illustrating the twoway interaction between CKD and arterial stiffness and mechanisms of accelerated progression of arterial stiffness in CKD are presented.

  1. Therapeutic modification of arterial stiffness: An update and comprehensive review

    OpenAIRE

    Wu, Ching-Fen; Liu, Pang-Yen; Wu, Tsung-Jui; Hung, Yuan; Yang, Shih-Ping; Lin, Gen-Min

    2015-01-01

    Arterial stiffness has been recognized as a marker of cardiovascular disease and associated with long-term worse clinical outcomes in several populations. Age, hypertension, smoking, and dyslipidemia, known as traditional vascular risk factors, as well as diabetes, obesity, and systemic inflammation lead to both atherosclerosis and arterial stiffness. Targeting multiple modifiable risk factors has become the main therapeutic strategy to improve arterial stiffness in patients at high cardiovas...

  2. Association of Parental Hypertension With Arterial Stiffness in Nonhypertensive Offspring

    DEFF Research Database (Denmark)

    Andersson, Charlotte; Quiroz, Rene; Enserro, Danielle

    2016-01-01

    High arterial stiffness seems to be causally involved in the pathogenesis of hypertension. We tested the hypothesis that offspring of parents with hypertension may display higher arterial stiffness before clinically manifest hypertension, given that hypertension is a heritable condition. We compa...

  3. Noninvasive pulse wave analysis for the determination of central artery stiffness

    DEFF Research Database (Denmark)

    Wittrock, Marc; Scholze, Alexandra; Compton, Friederike;

    2009-01-01

    Central artery stiffness predicts cardiovascular structural damage and clinical outcome. It is controversial whether central artery stiffness can be determined by noninvasive measurements. We compared noninvasive determination of central artery stiffness obtained from applanation tonometry of the...

  4. Hormones and arterial stiffness in patients with chronic kidney disease.

    Science.gov (United States)

    Gungor, Ozkan; Kircelli, Fatih; Voroneanu, Luminita; Covic, Adrian; Ok, Ercan

    2013-01-01

    Cardiovascular disease constitutes the major cause of mortality in patients with chronic kidney disease. Arterial stiffness is an important contributor to the occurrence and progression of cardiovascular disease. Various risk factors, including altered hormone levels, have been suggested to be associated with arterial stiffness. Based on the background that chronic kidney disease predisposes individuals to a wide range of hormonal changes, we herein review the available data on the association between arterial stiffness and hormones in patients with chronic kidney disease and summarize the data for the general population.

  5. Estimation of Stiffness Parameter on the Common Carotid Artery

    Science.gov (United States)

    Koya, Yoshiharu; Mizoshiri, Isao; Matsui, Kiyoaki; Nakamura, Takashi

    The arteriosclerosis is on the increase with an aging or change of our living environment. For that reason, diagnosis of the common carotid artery using echocardiogram is doing to take precautions carebropathy. Up to the present, several methods to measure stiffness parameter of the carotid artery have been proposed. However, they have analyzed at the only one point of common carotid artery. In this paper, we propose the method of analysis extended over a wide area of common carotid artery. In order to measure stiffness parameter of common carotid artery from echocardiogram, it is required to detect two border curves which are boundaries between vessel wall and blood. The method is composed of two steps. The first step is the detection of border curves, and the second step is the calculation of stiffness parameter using diameter of common carotid artery. Experimental results show the validity of the proposed method.

  6. Therapeutic modification of arterial stiffness: An update and comprehensive review.

    Science.gov (United States)

    Wu, Ching-Fen; Liu, Pang-Yen; Wu, Tsung-Jui; Hung, Yuan; Yang, Shih-Ping; Lin, Gen-Min

    2015-11-26

    Arterial stiffness has been recognized as a marker of cardiovascular disease and associated with long-term worse clinical outcomes in several populations. Age, hypertension, smoking, and dyslipidemia, known as traditional vascular risk factors, as well as diabetes, obesity, and systemic inflammation lead to both atherosclerosis and arterial stiffness. Targeting multiple modifiable risk factors has become the main therapeutic strategy to improve arterial stiffness in patients at high cardiovascular risk. Additionally to life style modifications, long-term ω-3 fatty acids (fish oil) supplementation in diet may improve arterial stiffness in the population with hypertension or metabolic syndrome. Pharmacological treatment such as renin-angiotensin-aldosterone system antagonists, metformin, and 3-hydroxy-3-methyl-glutaryl-CoA reductase inhibitors were useful in individuals with hypertension and diabetes. In obese population with obstructive sleep apnea, weight reduction, aerobic exercise, and continuous positive airway pressure treatment may also improve arterial stiffness. In the populations with chronic inflammatory disease such as rheumatoid arthritis, a use of antibodies against tumor necrosis factor-alpha could work effectively. Other therapeutic options such as renal sympathetic nerve denervation for patients with resistant hypertension are investigated in many ongoing clinical trials. Therefore our comprehensive review provides knowledge in detail regarding many aspects of pathogenesis, measurement, and management of arterial stiffness in several populations, which would be helpful for physicians to make clinical decision.

  7. Crosstalk between oxidative and nitrosative stress and arterial stiffness.

    Science.gov (United States)

    Mozos, Ioana; Luca, Constantin Tudor

    2017-02-01

    Arterial stiffness, the expression of reduced arterial elasticity, is an effective predictor of cardiovascular disorders. Oxidative stress is an imbalance between exposure to toxic reactive oxygen species (ROS) and antioxidant systems. The increase in reactive nitrogen species (RNS) is termed nitrosative stress. We review the main mechanisms and products linking arterial stiffness with oxidative and nitrosative stress in several disorders, focusing on recent experimental and clinical data, and the mechanisms explaining benefits of antioxidant therapy. Oxidative and nitrosative stress play important roles in arterial stiffness elevation in several disorders, including diabetes mellitus, hypertension, metabolic syndrome, obesity, peripheral arterial disease, chronic obstructive pulmonary disease, systemic lupus erythematosus, thalassemia, Kawasaki disease and malignant disorders. Oxidative and nitrosative stress are responsible for endothelial dysfunction due to uncoupling of the nitric oxide synthase, oxidative damage to lipids, proteins and DNA in vascular endothelial cells, associated with inflammation, arteriosclerosis and atherosclerosis. Regular physical exercise, caloric restriction, red wine, statins, sartans, metformin, oestradiol, curcumin and combinations of antioxidant vitamins are therapeutic strategies that may decrease arterial stiffness and oxidative stress thus reducing the risk of cardiovascular events. ROS and RNS represent potential therapeutic targets for preventing progression of arterial stiffness.

  8. Experimental exposure to diesel exhaust increases arterial stiffness in man

    Directory of Open Access Journals (Sweden)

    Newby David E

    2009-03-01

    Full Text Available Abstract Introduction Exposure to air pollution is associated with increased cardiovascular morbidity, although the underlying mechanisms are unclear. Vascular dysfunction reduces arterial compliance and increases central arterial pressure and left ventricular after-load. We determined the effect of diesel exhaust exposure on arterial compliance using a validated non-invasive measure of arterial stiffness. Methods In a double-blind randomized fashion, 12 healthy volunteers were exposed to diesel exhaust (approximately 350 μg/m3 or filtered air for one hour during moderate exercise. Arterial stiffness was measured using applanation tonometry at the radial artery for pulse wave analysis (PWA, as well as at the femoral and carotid arteries for pulse wave velocity (PWV. PWA was performed 10, 20 and 30 min, and carotid-femoral PWV 40 min, post-exposure. Augmentation pressure (AP, augmentation index (AIx and time to wave reflection (Tr were calculated. Results Blood pressure, AP and AIx were generally low reflecting compliant arteries. In comparison to filtered air, diesel exhaust exposure induced an increase in AP of 2.5 mmHg (p = 0.02 and in AIx of 7.8% (p = 0.01, along with a 16 ms reduction in Tr (p = 0.03, 10 minutes post-exposure. Conclusion Acute exposure to diesel exhaust is associated with an immediate and transient increase in arterial stiffness. This may, in part, explain the increased risk for cardiovascular disease associated with air pollution exposure. If our findings are confirmed in larger cohorts of susceptible populations, this simple non-invasive method of assessing arterial stiffness may become a useful technique in measuring the impact of real world exposures to combustion derived-air pollution.

  9. Associations between bicycling and carotid arterial stiffness in adolescents

    DEFF Research Database (Denmark)

    Ried-Larsen, M; Grøntved, A; Østergaard, Lars;

    2015-01-01

    The aim of the study was to investigate the associations between bicycling and carotid arterial stiffness, independent of objectively measured moderate-and-vigorous physical activity. This cross-sectional study included 375 adolescents (age 15.7 ± 0.4 years) from the Danish site of the European...... Youth Heart Study. Total frequency of bicycle usage was assessed by self-report, and carotid arterial stiffness was assessed using B-mode ultrasound. After adjusting for pubertal status, body height, and objectively measured physical activity and other personal lifestyle and demographic factors, boys...... modulus [standard beta -0.48 (95% CI -0.91 to -0.06)]. Similar trends were observed when investigating the association between commuter bicycling and carotid arterial stiffness. These associations were not observed in girls. Our observations suggest that increasing bicycling in adolescence may...

  10. Modifiable risk factors for increased arterial stiffness in outpatient nephrology.

    Science.gov (United States)

    Elewa, Usama; Fernandez-Fernandez, Beatriz; Alegre, Raquel; Sanchez-Niño, Maria D; Mahillo-Fernández, Ignacio; Perez-Gomez, Maria Vanessa; El-Fishawy, Hussein; Belal, Dawlat; Ortiz, Alberto

    2015-01-01

    Arterial stiffness, as measured by pulse wave velocity (PWV), is an independent predictor of cardiovascular events and mortality. Arterial stiffness increases with age. However, modifiable risk factors such as smoking, BP and salt intake also impact on PWV. The finding of modifiable risk factors may lead to the identification of treatable factors, and, thus, is of interest to practicing nephrologist. We have now studied the prevalence and correlates of arterial stiffness, assessed by PWV, in 191 patients from nephrology outpatient clinics in order to identify modifiable risk factors for arterial stiffness that may in the future guide therapeutic decision-making. PWV was above normal levels for age in 85/191 (44.5%) patients. Multivariate analysis showed that advanced age, systolic BP, diabetes mellitus, serum uric acid and calcium polystyrene sulfonate therapy or calcium-containing medication were independent predictors of PWV. A new parameter, Delta above upper limit of normal PWV (Delta PWV) was defined to decrease the weight of age on PWV values. Delta PWV was calculated as (measured PWV) - (upper limit of the age-adjusted PWV values for the general population). Mean±SD Delta PWV was 0.76±1.60 m/sec. In multivariate analysis, systolic blood pressure, active smoking and calcium polystyrene sulfonate therapy remained independent predictors of higher delta PWV, while age, urinary potassium and beta blocker therapy were independent predictors of lower delta PWV. In conclusion, arterial stiffness was frequent in nephrology outpatients. Systolic blood pressure, smoking, serum uric acid, calcium-containing medications, potassium metabolism and non-use of beta blockers are modifiable factors associated with increased arterial stiffness in Nephrology outpatients.

  11. Modifiable risk factors for increased arterial stiffness in outpatient nephrology.

    Directory of Open Access Journals (Sweden)

    Usama Elewa

    Full Text Available Arterial stiffness, as measured by pulse wave velocity (PWV, is an independent predictor of cardiovascular events and mortality. Arterial stiffness increases with age. However, modifiable risk factors such as smoking, BP and salt intake also impact on PWV. The finding of modifiable risk factors may lead to the identification of treatable factors, and, thus, is of interest to practicing nephrologist. We have now studied the prevalence and correlates of arterial stiffness, assessed by PWV, in 191 patients from nephrology outpatient clinics in order to identify modifiable risk factors for arterial stiffness that may in the future guide therapeutic decision-making. PWV was above normal levels for age in 85/191 (44.5% patients. Multivariate analysis showed that advanced age, systolic BP, diabetes mellitus, serum uric acid and calcium polystyrene sulfonate therapy or calcium-containing medication were independent predictors of PWV. A new parameter, Delta above upper limit of normal PWV (Delta PWV was defined to decrease the weight of age on PWV values. Delta PWV was calculated as (measured PWV - (upper limit of the age-adjusted PWV values for the general population. Mean±SD Delta PWV was 0.76±1.60 m/sec. In multivariate analysis, systolic blood pressure, active smoking and calcium polystyrene sulfonate therapy remained independent predictors of higher delta PWV, while age, urinary potassium and beta blocker therapy were independent predictors of lower delta PWV. In conclusion, arterial stiffness was frequent in nephrology outpatients. Systolic blood pressure, smoking, serum uric acid, calcium-containing medications, potassium metabolism and non-use of beta blockers are modifiable factors associated with increased arterial stiffness in Nephrology outpatients.

  12. Arterial wall stiffness in patients with essential hypertension at young age

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    Kolesnik E.L.

    2014-11-01

    Full Text Available Research objective was investigating arterial wall stiffness in patients with hypertension at young age and assessing the relationship between subclinical target organs damage and ambulatory blood pressure monitoring (ABPM parameters. 30 male patients aged 18-35 years with essential hypertension stage I and II, hypertension 1 and 2nd grade were surveyed. The examination included general clinical methods, echocardiography, ABPM and suprasystolic sfigmography. It was found that the pulse wave velocity (PWVao (r = 0,557 p <0,01, central aortic blood pressure (SBPao (r = 0,492 p <0,01 and augmentation index (AIxao (r = 0,489 p <0.01 significantly increased with the pa¬tients’ age. Abdominal obesity (r = 0,566 p <0,01 and BMI (r = 0,599 p <0,01 impacted on the PWVao acceleration. Increasing of the left ventricular mass index (LVMI is highly associated with SBPao (r = 0,506 p <0,05 and PWVao (r = 0,434 p <0,05. According to ABPM the most significant correlation with arterial wall stiffness parameters demon¬strated diastolic blood pressure (DBP daytime level (AIxao (r = 0,418 p <0,01, with PWVao (r = 0,699 p <0.01 and SBPao (r = 0,695 p <0,01. Thus, age, excessive body weight and obesity should be considered as unfavorable factors that worsen arterial wall stiffness in patients with hypertension at the age before 35 years. Increase of DBP levels especially during the day causes maximum negative impact on the arterial wall stiffness parameters according to ABPM. Increased SBPao and PWVao in patients with hypertension at a young age are associated with increased left ventricular mass index.

  13. The Contribution of Osteoprogenitor Cells to Arterial Stiffness and Hypertension.

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    Pikilidou, Maria; Yavropoulou, Maria; Antoniou, Maria; Yovos, John

    2015-01-01

    Hypertension, the major cause of cardiovascular disease, is bidirectionally linked to arterial stiffness. Evidence shows that vascular calcification, either medial or intimal, induces arterial stiffening further worsening hypertension parallel to substantially increasing cardiovascular risk. The disturbance in the bone-vascular axis that leads to the increase of calcium deposition in the arterial wall may be the result of a shift in the functionality of bone marrow-derived circulating stem cells with a calcifying potential, namely osteoprogenitor cells. These cells deposit bone matrix proteins in the vascular wall that can subsequently become mineralized. The current notion is that these cells derive from diverse cell lines. The present review summarizes the current knowledge on the role of progenitor cells with a calcifying potential on arterial calcification, stiffness and hypertension.

  14. AGE, ARTERIAL STIFFNESS AND CARDIOVASCULAR RISK

    Institute of Scientific and Technical Information of China (English)

    蒋雄京; 刘国仗; 刘力生

    2001-01-01

    The recent researches on the structure and function of large artery find that increasing pulse pressure is associated with greater cardiovascular risk, especially risk of coronary events. Such risk is not explicable on the basis of increasing systolic pressure with age, and is apparent even when the major reason for increased pulse pressure is a relative decrease of diastolic pressure. The finding challenges the conventional approach to arterial pressure where diastolic pressure is traditionally viewed as the most robust indicator of caridovascular risk. An explanation is available. This is based on the perception of Harriet Dustan that hypertension in the older popula-

  15. Pre-diabetes and arterial stiffness in uraemic patients

    DEFF Research Database (Denmark)

    Hornum, Mads; Clausen, Peter; Kjaergaard, Jesper;

    2010-01-01

    In order to address factors of relevance for new onset diabetes mellitus and cardiovascular disease after kidney transplantation, we investigated the presence of pre-diabetes, arterial stiffness and endothelial dysfunction in patients with end-stage renal disease (ESRD) accepted for kidney...

  16. Arterial Stiffness in Nonhypertensive Type 2 Diabetes Patients in Ghana

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    Antwi, Daniel A.; Gyan, Ben

    2016-01-01

    Background. Increased arterial stiffness is an independent cardiovascular risk factor in diabetes patients and general population. However, the contribution of diabetes to arterial stiffness is often masked by coexistent obesity and hypertension. In this study, we assessed arterial stiffness in nonhypertensive, nonobese type 2 diabetes (T2DM) patients in Ghana. Methods. In case-control design, 166 nonhypertensive, nonobese participants, comprising 96 T2DM patients and 70 nondiabetes controls, were recruited. Peripheral and central blood pressure (BP) indices were measured, and arterial stiffness was assessed as aortic pulse wave velocity (PWVao), augmentation index (AIx), cardioankle vascular index (CAVI), and heart-ankle pulse wave velocity (haPWV). Results. With similar peripheral and central BP indices, T2DM patients had higher PWVao (8.3 ± 1 versus 7.8 ± 1.3, p = 0.044) and CAVI (7.9 ± 1.2 versus 6.9 ± 0.7, p = 0.021) than nondiabetic control. AIx and haPWV were similar between T2DM and nondiabetic controls. Multiple regression models showed that, in the entire study participants, the major determinants of PWVao were diabetes status, age, gender, systolic BP, and previous smoking status (β = 0.22, 0.36, 0.48, 0.21, and 0.25, resp.; all p < 0.05); the determinants of CAVI were diabetes status, age, BMI, heart rate, HbA1c, total cholesterol, HDL cholesterol, and previous smoking status (β = 0.21, 0.38, 0.2, 0.18, 0.24. 0.2, −0.19, and 0.2, resp.; all p < 0.05). Conclusion. Our findings suggest that nonhypertensive, nonobese T2DM patients have increased arterial stiffness without appreciable increase in peripheral and central pressure indices.

  17. Arterial stiffness, central hemodynamics, and cardiovascular risk in hypertension

    Directory of Open Access Journals (Sweden)

    Palatini P

    2011-12-01

    Full Text Available Paolo Palatini1, Edoardo Casiglia1, Jerzy Gąsowski2, Jerzy Głuszek3, Piotr Jankowski4, Krzysztof Narkiewicz5, Francesca Saladini1, Katarzyna Stolarz-Skrzypek4, Valérie Tikhonoff1, Luc Van Bortel6, Wiktoria Wojciechowska4, Kalina Kawecka-Jaszcz41Department of Clinical and Experimental Medicine, University of Padova, Padua, Italy; 2Department of Internal Medicine and Gerontology, Jagiellonian University Medical College, Kraków, Poland; 3Department of Arterial Hypertension, University Hospital, Poznan, Poland; 4First Department of Cardiology and Hypertension, Jagiellonian University Medical College, Kraków, Poland; 5Department of Hypertension and Diabetology, Medical University of Gdansk, Gdansk, Poland; 6Heymans Institute of Pharmacology, Ghent University, Ghent, BelgiumAbstract: This review summarizes several scientific contributions at the recent Satellite Symposium of the European Society of Hypertension, held in Milan, Italy. Arterial stiffening and its hemodynamic consequences can be easily and reliably measured using a range of noninvasive techniques. However, like blood pressure (BP measurements, arterial stiffness should be measured carefully under standardized patient conditions. Carotid-femoral pulse wave velocity has been proposed as the gold standard for arterial stiffness measurement and is a well recognized predictor of adverse cardiovascular outcome. Systolic BP and pulse pressure in the ascending aorta may be lower than pressures measured in the upper limb, especially in young individuals. A number of studies suggest closer correlation of end-organ damage with central BP than with peripheral BP, and central BP may provide additional prognostic information regarding cardiovascular risk. Moreover, BP-lowering drugs can have differential effects on central aortic pressures and hemodynamics compared with brachial BP. This may explain the greater beneficial effect provided by newer antihypertensive drugs beyond peripheral BP

  18. Cardiac Organ Damage and Arterial Stiffness in Autonomic Failure: Comparison With Essential Hypertension.

    Science.gov (United States)

    Milazzo, Valeria; Maule, Simona; Di Stefano, Cristina; Tosello, Francesco; Totaro, Silvia; Veglio, Franco; Milan, Alberto

    2015-12-01

    Autonomic failure (AF) is characterized by orthostatic hypotension, supine hypertension, and increased blood pressure (BP) variability. AF patients develop cardiac organ damage, similarly to essential hypertension (EH), and have higher arterial stiffness than healthy controls. Determinants of cardiovascular organ damage in AF are not well known: both BP variability and mean BP values may be involved. The aim of the study was to evaluate cardiac organ damage, arterial stiffness, and central hemodynamics in AF, compared with EH subjects with similar 24-hour BP and a group of healthy controls, and to evaluate determinants of target organ damage in patients with AF. Twenty-seven patients with primary AF were studied (mean age, 65.7±11.2 years) using transthoracic echocardiography, carotid-femoral pulse wave velocity, central hemodynamics, and 24-hour ambulatory BP monitoring. They were compared with 27 EH subjects matched for age, sex, and 24-hour mean BP and with 27 healthy controls. AF and EH had similar left ventricular mass (101.6±33.3 versus 97.7±28.1 g/m(2), P=0.59) and carotid-femoral pulse wave velocity (9.3±1.8 versus 9.2±3.0 m/s, P=0.93); both parameters were significantly lower in healthy controls (Phypertensive heart disease and increased arterial stiffness, similar to EH with comparable mean BP values. Twenty-four-hour and nighttime systolic BP were determinants of cardiovascular damage, independent of BP variability.

  19. Association between arterial stiffness and peritoneal small solute transport rate.

    Science.gov (United States)

    Zhe, Xing-wei; Tian, Xin-kui; Chen, Wei; Guo, Li-juan; Gu, Yue; Chen, Hui-min; Tang, Li-jun; Wang, Tao

    2008-05-01

    While cardiovascular disease accounts for 40-50% of the mortality in dialysis patients, and while a high peritoneal transport in continuous ambulatory peritoneal dialysis (CAPD) is an independent predictor of outcome, it is unclear if there are any links. Aortic stiffness has become established as a cardiovascular risk factor. We thus studied pulse wave velocity (PWV) in CAPD patients to explore the possible link between peritoneal small solute transport and aortic stiffness. CAPD patients (n = 76, 27 M/49 F) in our center were included in the present study. Aortic stiffness was assessed by brachial pulse pressure (PP) and carotid-femoral PWV. Patients' peritoneal small solute transport rate was assessed by D/P(cr) at 4 h. Extracellular water over total body water (E/T ratio) was assessed by means of bioimpedance analysis. C-reactive protein was also measured. Carotid-femoral PWV was positively associated with patients' age (r = 0.555; P < 0.01), time on peritoneal dialysis (r = 0.332; P < 0.01), diabetic status (r = 0.319; P < 0.01), D/P(cr) (r = 0.241; P < 0.05), PP (r = 0.475; P < 0.01), and E/T (r = 0.606; P < 0.01). In a multivariate regression analysis, carotid-femoral PWV was independently determined by E/T (P < 0.01), PP (P < 0.01), age (P < 0.01), and D/P(cr) (P < 0.05). D/P(cr), in addition to E/T, age, and PP, was an independent predictor of elevated carotid-femoral PWV in CAPD patients, suggesting that there might be a link between high aortic stiffness and increased peritoneal small solute transport rate.

  20. Cystatin C Associates with Arterial Stiffness in Older Adults

    Science.gov (United States)

    Madero, Magdalena; Wassel, Christina L.; Peralta, Carmen A.; Najjar, Samer S.; Sutton-Tyrrell, Kim; Fried, Linda; Canada, Robert; Newman, Anne; Shlipak, Michael G.; Sarnak, Mark J.

    2009-01-01

    Large arteries commonly become stiff in kidney failure, but few studies have investigated arterial stiffness in earlier stages of kidney disease. We evaluated the association between kidney function and aortic pulse wave velocity (aPWV) and its potential modification by race, diabetes, or coronary heart disease in older adults. We measured aPWV in 2468 participants in the Health Aging and Body Composition (Health ABC) study; mean age was 73.7 yr, 40% were black, and 24% had diabetes. After categorizing kidney function into three groups on the basis of cystatin C level, multivariable analysis revealed that the medium and high cystatin C groups associated with a 5.3% (95% confidence interval 0.8 to 10.0%) and 8.0% (95% confidence interval 2.2 to 14.1%) higher aPWV than the low cystatin C group; however, chronic kidney disease, as defined by estimated GFR <60 ml/min per 1.73 m2, did not significantly associate with aPWV. We did not identify interactions between cystatin C and race, diabetes, or coronary heart disease. In conclusion, stiffness of large arteries, a major risk factor for cardiovascular disease, may partially mediate the association between cystatin C and cardiovascular risk in older adults. PMID:19357259

  1. Abnormal pulmonary artery stiffness in pulmonary arterial hypertension: in vivo study with intravascular ultrasound.

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    Edmund M T Lau

    Full Text Available BACKGROUND: There is increasing recognition that pulmonary artery stiffness is an important determinant of right ventricular (RV afterload in pulmonary arterial hypertension (PAH. We used intravascular ultrasound (IVUS to evaluate the mechanical properties of the elastic pulmonary arteries (PA in subjects with PAH, and assessed the effects of PAH-specific therapy on indices of arterial stiffness. METHOD: Using IVUS and simultaneous right heart catheterisation, 20 pulmonary segments in 8 PAH subjects and 12 pulmonary segments in 8 controls were studied to determine their compliance, distensibility, elastic modulus and stiffness index β. PAH subjects underwent repeat IVUS examinations after 6-months of bosentan therapy. RESULTS: AT BASELINE, PAH SUBJECTS DEMONSTRATED GREATER STIFFNESS IN ALL MEASURED INDICES COMPARED TO CONTROLS: compliance (1.50±0.11×10(-2 mm(2/mmHg vs 4.49±0.43×10(-2 mm(2/mmHg, p<0.0001, distensibility (0.32±0.03%/mmHg vs 1.18±0.13%/mmHg, p<0.0001, elastic modulus (720±64 mmHg vs 198±19 mmHg, p<0.0001, and stiffness index β (15.0±1.4 vs 11.0±0.7, p = 0.046. Strong inverse exponential associations existed between mean pulmonary artery pressure and compliance (r(2 = 0.82, p<0.0001, and also between mean PAP and distensibility (r(2 = 0.79, p = 0.002. Bosentan therapy, for 6-months, was not associated with any significant changes in all indices of PA stiffness. CONCLUSION: Increased stiffness occurs in the proximal elastic PA in patients with PAH and contributes to the pathogenesis RV failure. Bosentan therapy may not be effective at improving PA stiffness.

  2. Arterial Stiffness in Patients Taking Second-generation Antipsychotics

    Science.gov (United States)

    Fındıklı, Ebru; Gökçe, Mustafa; Nacitarhan, Vedat; Camkurt, Mehmet Akif; Fındıklı, Hüseyin Avni; Kardaş, Selçuk; Şahin, Merve Coşgun; Karaaslan, Mehmet Fatih

    2016-01-01

    Objective That treatment with second-generation antipsychotics (SGAs) causes metabolic side effects and atherosclerosis in patients with schizophrenia and bipolar disorder (BD) is well-known. Increased arterial stiffness is an important marker of arteriosclerosis and has been identified as an independent risk factor for cardiovascular diseases. We measured pulse wave velocity (PWV) as a marker of arteriosclerosis in patients with schizophrenia and BD who use SGAs. Methods Patients and controls were collected from our psychiatry outpatient clinics or family medicine. Mental illness was diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, 4th edition. Mean age, gender, systolic and diastolic blood pressure, body mass index, Framingham risk score (FRS), etc. were determined. Simultaneous electrocardiography and pulse wave were recorded with an electromyography device. The photo-plethysmographic method was used to record the pulse wave. Inclusion criteria included use of SGAs for at least the last six months. Patients with diseases that are known to cause stiffness and the use of typical antipsychotics were excluded. Results Ninety-six subject (56 patients, 40 controls) were included in our study. There were 49 females, 47 males. Patients had schizophrenia (n=17) and BD (n=39). Their treatments were quetiapine (n=15), risperidone (n=13), olanzapine (n=15), and aripiprazole (n=13). Although differences in mean age, gender, and FRS in the patient and control groups were not statistically significant (p=1), PWV was greater in patients in the antipsychotic group (p=0.048). Conclusion This study supported the liability to stiffness in patients with schizophrenia and BD. Using SGAs may contribute to arterial stiffness in these patients. PMID:27776389

  3. Effects of safflower seed extract on arterial stiffness

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    Katsuya Suzuki

    2010-11-01

    Full Text Available Katsuya Suzuki1, Shigekazu Tsubaki2, Masami Fujita3, Naoto Koyama1, Michio Takahashi1, Kenji Takazawa41Research Institute for Health Fundamentals, Ajinomoto Co., Inc., Kawasaki; 2Samoncho Clinic, Tokyo; 3Shinanozaka Clinic, Tokyo; 4Tokyo Medical University Hachioji Medical Center, Tokyo, JapanAbstract: Safflower seed extract (SSE contains characteristic polyphenols and serotonin derivatives (N-(p-coumaroyl serotonin and N-feruloylserotonin, which are reported to inhibit oxidation of low-density lipoprotein (LDL, formation of atherosclerotic plaques, and improve arterial stiffness as assessed by pulse wave analysis in animal models. The effects of long-term supplementation with SSE on arterial stiffness in human subjects were evaluated. This double-blind, placebo-controlled study was conducted in 77 males (35–65 years and 15 postmenopausal females (55–65 years with high-normal blood pressure or mild hypertension who were not undergoing treatment. Subjects received SSE (70 mg/day as serotonin derivatives or placebo for 12 weeks, and pulse wave measurements, ie, second derivative of photoplethysmogram (SDPTG, augmentation index, and brachial-ankle pulse wave velocity (baPWV were conducted at baseline, and at weeks 4, 8, and 12. Vascular age estimated by SDPTG aging index improved in the SSE-supplemented group when compared with the placebo group at four (P = 0.0368 and 12 weeks (P = 0.0927. The trend of augmentation index reduction (P = 0.072 versus baseline was observed in the SSE-supplemented group, but reduction of baPWV by SSE supplementation was not observed. The SSE-supplemented group also showed a trend towards a lower malondialdehyde-modified-LDL autoantibody titer at 12 weeks from baseline. These results suggest long-term ingestion of SSE in humans could help to improve arterial stiffness.Keywords: safflower, serotonin derivatives, antioxidants, augmentation index, pulse wave velocity

  4. Correlation of arterial stiffness index with carotid atherosclerosis in patients with primary hypertension

    Institute of Scientific and Technical Information of China (English)

    Wen-Hua Cai; Li-Min Li; Xue-Min Wang; Cui-Qing Sun; Hai-Wei Zhao; Hui Wang; Rui-Chao Liu

    2016-01-01

    Objective:To explore the correlation of arterial stiffness index with carotid atherosclerosis in patients with primary hypertension.Methods:A total of 86 patients with primary hypertension who were admitted in our hospital from January, 2013 to September, 2015 were included in the study, and divided into the carotid atherosclerosis group (IMT≥0.9 mm, with plaque being detected) and the pure hypertension group (normal IMT) according to the carotid artery color Doppler ultrasound results. According to the ambulatory blood pressure monitoring results, the carotid atherosclerosis group was divided into the low BPV (7.02-9.57) group and the high BPV (>9.57-14.29) group. The non-invasive ambulatory blood pressure monitoring apparatus was used for 24 h blood pressure monitoring, measuring time in the daytime: 6:00-21:59, measuring one time every 30 min; measuring time in the nighttime: 22:00-5:59, measuring one time every 60 min. The dSBP, dDBP, nSBP, nDBP, 24 h SBP, and 24 h DBP were recorded. BPV was expressed as 24 h SCV and 24 h DCV.Results:The dSBP, nSBP, 24 h SBP, 24 h DBP, and 24 h SCV in the carotid atherosclerosis group were significantly higher than those in the pure hypertension group, while the comparison of dDBP, nDBP, and 24 h DCV between the two groups was not statistically significant. The common carotid artery and external carotid artery IMT, and the mean IMT in the high BPV group were significantly higher than those in the low BPV group, and the number of carotid plaques being detected was significantly greater than that in the low BPV group.Conclusions:BPV is involved in the arterial functional and structural changes, resulting in the target organ damage. Detection of carotid IMT is of great significance in evaluating the early vascular damage and predicting the cardiovascular events; therefore, BPV monitoring should be strengthened during the diagnosis and treatment of hypertension.

  5. An update on the role of adipokines in arterial stiffness and hypertension.

    Science.gov (United States)

    Sabbatini, Andréa R; Fontana, Vanessa; Laurent, Stephane; Moreno, Heitor

    2015-03-01

    Adipokines are hormones produced by adipocytes and have been involved in multiple pathologic pathways, including inflammatory and cardiovascular complications in essential hypertension. Arterial stiffness is a frequent vascular complication that represents increased cardiovascular risk in hypertensive patients. Adipokines, such as adiponectin, leptin and resistin, might be implicated in hypertension, as well as in vascular alterations associated with this condition. Arterial stiffness has proven to be a predictor of cardiovascular events. Obesity and target-organ damage such as arterial stiffness are features associated with hypertension. This review aims to update the association between adipokines and arterial stiffness in essential and resistant hypertension (RHTN).

  6. Aerobic exercise training increases plasma Klotho levels and reduces arterial stiffness in postmenopausal women.

    Science.gov (United States)

    Matsubara, Tomoko; Miyaki, Asako; Akazawa, Nobuhiko; Choi, Youngju; Ra, Song-Gyu; Tanahashi, Koichiro; Kumagai, Hiroshi; Oikawa, Satoshi; Maeda, Seiji

    2014-02-01

    The Klotho gene is a suppressor of the aging phenomena, and the secretion as well as the circulation of Klotho proteins decrease with aging. Although habitual exercise has antiaging effects (e.g., a decrease in arterial stiffness), the relationship between Klotho and habitual exercise remains unclear. In the present study, we investigated the effect of habitual exercise on Klotho, with a particular focus on arterial stiffness. First, we examined the correlation between plasma Klotho concentration and arterial stiffness (carotid artery compliance and β-stiffness index) or aerobic exercise capacity [oxygen uptake at ventilatory threshold (VT)] in 69 healthy, postmenopausal women (50-76 years old) by conducting a cross-sectional study. Second, we tested the effects of aerobic exercise training on plasma Klotho concentrations and arterial stiffness. A total of 19 healthy, postmenopausal women (50-76 years old) were divided into two groups: control group and exercise group. The exercise group completed 12 wk of moderate aerobic exercise training. In the cross-sectional study, plasma Klotho concentrations positively correlated with carotid artery compliance and VT and negatively correlated with the β-stiffness index. In the interventional study, aerobic exercise training increased plasma Klotho concentrations and carotid artery compliance and decreased the β-stiffness index. Moreover, the changes in plasma Klotho concentration and arterial stiffness were found to be correlated. These results suggest a possible role for secreted Klotho in the exercise-induced modulation of arterial stiffness.

  7. Critical appraisal of the differential effects of antihypertensive agents on arterial stiffness

    Directory of Open Access Journals (Sweden)

    Francesca Kum

    2010-06-01

    Full Text Available Francesca Kum, Janaka KarallieddeUnit for Metabolic Medicine, Cardiovascular Division, Kings College-Waterloo Campus, King’s College London, United KingdomAbstract: Increased central arterial stiffness, involving accelerated vascular ageing of the aorta, is a powerful and independent risk factor for early mortality and provides prognostic information above and beyond traditional risk factors for cardiovascular disease (CVD. Central arterial stiffness is an important determinant of pulse pressure; therefore, any pathological increase may result in left ventricular hypertrophy and impaired coronary perfusion. Central artery stiffness can be assessed noninvasively by measurement of aortic pulse wave velocity, which is the gold standard for measurement of arterial stiffness. Earlier, it was believed that changes in arterial stiffness, which are primarily influenced by long-term pressure-dependent structural changes, may be slowed but not reversed by pharmacotherapy. Recent studies with drugs that inhibit the renin–angiotensin–aldosterone system, advanced glycation end products crosslink breakers, and endothelin antagonists suggest that blood pressure (BP-independent reduction and reversal of arterial stiffness are feasible. We review the recent literature on the differential effect of antihypertensive agents either as monotherapy or combination therapy on arterial stiffness. Arterial stiffness is an emerging therapeutic target for CVD risk reduction; however, further clinical trials are required to confirm whether BP-independent changes in arterial stiffness directly translate to a reduction in CVD events.Keywords: aortic pulse wave velocity, augmentation index, blood pressure, renin–angiotensin–aldosterone system

  8. Arterial stiffness & Sri Lankan chronic kidney disease of unknown origin

    Science.gov (United States)

    Gifford, Fiona; Kimmitt, Robert; Herath, Chula; Webb, David J.; Melville, Vanessa; Siribaddana, Sisira; Eddleston, Michael; Dhaun, Neeraj

    2016-09-01

    Chronic kidney disease (CKD) is common and independently associated with cardiovascular disease (CVD). Arterial stiffness contributes to CVD risk in CKD. In many developing countries a considerable proportion of CKD remains unexplained, termed CKDu. We assessed arterial stiffness in subjects with Sri Lankan CKDu, in matched controls without CKD and in those with defined CKD. Aortic blood pressure (BP), pulse wave velocity (PWV) and augmentation index (AIx) were assessed in 130 subjects (50 with CKDu, 45 with CKD and 35 without CKD) using the validated TensioMed™ Arteriograph monitor. Brachial and aortic BP was lower in controls than in CKDu and CKD subjects but no different between CKDu and CKD. Controls had a lower PWV compared to subjects with CKDu and CKD. Despite equivalent BP and renal dysfunction, CKDu subjects had a lower PWV than those with CKD (8.7 ± 1.5 vs. 9.9 ± 2.2 m/s, p groups (controls vs. CKDu vs. CKD: 6.7 ± 0.9 vs. 8.7 ± 1.5 vs. 10.4 ± 1.5 m/s, p < 0.001 for all). Sri Lankan CKDu is associated with less arterial stiffening than defined causes of CKD. Whether this translates to lower cardiovascular morbidity and mortality long term is unclear and should be the focus of future studies.

  9. Early detection and treatment of myocardial ischaemia after operation using continual ambulatory arterial pressure monitoring and ECG ST segment analysis.

    Science.gov (United States)

    Edwards, N D; Troy, G; Yeo, W; Jackson, P; Reilly, C S

    1995-10-01

    We report a case in which the use of continual ambulatory arterial pressure monitoring and ECG ST-segment analysis allowed early detection and treatment of myocardial ischaemia in the postoperative period. We believe that this case illustrates the potential value of ambulatory monitoring in the early postoperative period in high-risk patients.

  10. Active ambulatory care management supported by short message services and mobile phone technology in patients with arterial hypertension.

    Science.gov (United States)

    Kiselev, Anton R; Gridnev, Vladimir I; Shvartz, Vladimir A; Posnenkova, Olga M; Dovgalevsky, Pavel Ya

    2012-01-01

    The use of short message services and mobile phone technology for ambulatory care management is the most accessible and most inexpensive way to transition from traditional ambulatory care management to active ambulatory care management in patients with arterial hypertension (AH). The aim of this study was to compare the clinical efficacy of active ambulatory care management supported by short message services and mobile phone technology with traditional ambulatory care management in AH patients. The study included 97 hypertensive patients under active ambulatory care management and 102 patients under traditional ambulatory care management. Blood pressure levels, body mass, and smoking history of patients were analyzed in the study. The duration of study was 1 year. In the active ambulatory care management group, 36% of patients were withdrawn from the study within a year. At the end of the year, 77% of patients from the active care management group had achieved the goal blood pressure level. That was more than 5 times higher than that in the traditional ambulatory care management group (P mobile phone improves the quality of ambulatory care of hypertensive patients.

  11. Impaired renal allograft function is associated with increased arterial stiffness in renal transplant recipients

    DEFF Research Database (Denmark)

    Kneifel, M; Scholze, A; Burkert, A;

    2006-01-01

    It is important whether impairment of renal allograft function may deteriorate arterial stiffness in renal transplant recipients. In a cross-sectional study, arterial vascular characteristics were non-invasively determined in 48 patients with renal allograft using applanation tonometry and digital...... of large arteries S1 and small arteries S2 in renal transplant recipients (each p renal allograft (p ...-Wallis test between groups). It is concluded that impairment of renal allograft function is associated with an increased arterial stiffness in renal transplant recipients....

  12. The Effect of High Dose Cholecalciferol on Arterial Stiffness and Peripheral and Central Blood Pressure in Healthy Humans

    DEFF Research Database (Denmark)

    Bressendorff, Iain; Brandi, Lisbet; Schou, Morten

    2016-01-01

    and blood pressure in healthy normotensive adults. METHODS: 40 healthy adults were randomised in this double-blinded study to either oral cholecalciferol 3000 IU/day or matching placebo and were followed for 16 weeks to examine any effects on pulse wave velocity (PWV), augmentation index (AIx), peripheral...... and central blood pressure and 24-hour ambulatory blood pressure. RESULTS: 22 subjects in the cholecalciferol arm and 18 subjects in the placebo arm completed the 16 weeks of follow-up. There was no difference in changes in PWV, AIx corrected for heart rate or central or peripheral blood pressure between...... the two groups. There was no correlation between serum 25-hydroxy vitamin D and any of these parameters. CONCLUSIONS: Oral cholecalciferol 3000 IU/day does not affect arterial stiffness or blood pressure after 16 weeks of treatment in healthy normotensive adults. TRIAL REGISTRATION: ClinicalTrials.gov NCT...

  13. Noninvasive 24-hour ambulatory arterial blood pressure monitoring in cirrhosis

    DEFF Research Database (Denmark)

    Møller, Søren; Wiinberg, N; Henriksen, Jens Henrik

    1995-01-01

    Cirrhotic patients have disturbed systemic hemodynamics with reduced arterial blood pressure, but this has not been investigated during daily activity and sleep. Systolic (SBP), diastolic (DBP), and mean arterial blood pressure (MAP), and heart rate (HR) were measured by an automatic ambulant...... device for monitoring blood pressure in 35 patients with cirrhosis and 35 healthy matched controls. During the daytime, SBP, DBP, and MAP were significantly lower in the patients than in the controls (median 118 vs. 127; 70 vs. 78; 86 vs. 94 mm Hg, P blood pressures...... were almost similar in the two groups (108 vs. 110; 65 vs. 67; 78 vs. 82 mm Hg, NS). Conversely, HR was significantly higher in the patients both in the daytime (86 vs. 72/min, P blood pressure and HR from daytime...

  14. Noninvasive 24-hour ambulatory arterial blood pressure monitoring in cirrhosis

    DEFF Research Database (Denmark)

    Møller, Søren; Wiinberg, N; Henriksen, Jens Henrik

    1995-01-01

    were almost similar in the two groups (108 vs. 110; 65 vs. 67; 78 vs. 82 mm Hg, NS). Conversely, HR was significantly higher in the patients both in the daytime (86 vs. 72/min, P pressure and HR from daytime......Cirrhotic patients have disturbed systemic hemodynamics with reduced arterial blood pressure, but this has not been investigated during daily activity and sleep. Systolic (SBP), diastolic (DBP), and mean arterial blood pressure (MAP), and heart rate (HR) were measured by an automatic ambulant...... device for monitoring blood pressure in 35 patients with cirrhosis and 35 healthy matched controls. During the daytime, SBP, DBP, and MAP were significantly lower in the patients than in the controls (median 118 vs. 127; 70 vs. 78; 86 vs. 94 mm Hg, P pressures...

  15. Arterial stiffness and sedentary lifestyle: Role of oxidative stress.

    Science.gov (United States)

    Lessiani, Gianfranco; Santilli, Francesca; Boccatonda, Andrea; Iodice, Pierpaolo; Liani, Rossella; Tripaldi, Romina; Saggini, Raoul; Davì, Giovanni

    2016-04-01

    Sedentary lifestyle is a risk factor for the development of cardiovascular disease, and leads to a quantifiable impairment in vascular function and arterial wall stiffening. We tested the hypothesis of oxidative stress as a determinant of arterial stiffness (AS) in physically inactive subjects, and challenged the reversibility of these processes after the completion of an eight-week, high-intensity exercise training (ET). AS was assessed before and after ET, measuring carotid to femoral pulse wave velocity (PWV) with a Vicorder device. At baseline and after ET, participants performed urine collection and underwent fasting blood sampling. Urinary 8-iso-PGF2α, an in vivo marker of lipid peroxidation, total, HDL and LDL cholesterol, and triglyceride concentrations were measured. ET was associated with significantly reduced urinary 8-iso-PGF2α(p<0.0001) levels. PWV was significantly reduced after ET completion (p<0.0001), and was directly related to urinary 8-iso-PGF2α(Rho=0.383, p=0.021). After ET, cardiovascular fitness improved [peak oxygen consumption (p<0.0001), peak heart rate (p<0.0001)]. However, no improvement in lipid profile was observed, apart from a significant reduction of triglycerides (p=0.022). PWV and triglycerides were significantly related (Rho=0.466, p=0.005) throughout the study period. PWV levels were also related to urinary 8-iso-PGF2α in our previously sedentary subjects. We conclude that regular physical exercise may be a natural antioxidant strategy, lowering oxidant stress and thereby the AS degree.

  16. Prognostic value of changes in arterial stiffness in men with coronary artery disease

    Directory of Open Access Journals (Sweden)

    Iana A Orlova

    2010-11-01

    Full Text Available Iana A Orlova, Eradzh Yu Nuraliev, Elena B Yarovaya, Fail T AgeevOutpatient department, Russian Cardiology Research Center, Moscow, Russian Federation Background: Men with coronary artery disease (CAD have been shown to have enhanced arterial stiffness. Arterial function may change over time according to treatment, but the prognostic value of these changes has not been investigated.Objectives: The aim of the present study was to assess whether an improvement in large artery rigidity in response to treatment, could predict a more favorable prognosis in a population of men with CAD.Methods: A total of 161 men with CAD (mean age 56.8 ± 10.9 years being treated with conventional therapy underwent brachial-ankle pulse wave velocity (PWVba measurements at baseline and after six months. Follow-up period was 3.5 years. End-points were major adverse cardiac events (MACE: acute myocardial infarction, unstable angina, coronary intervention, or cardiac death.Results: During the three-year follow-up period (since initial six-month follow-up, 30 patients experienced MACE. After six-month follow-up, PWVba had not improved (∆PWVba ≥ 0%, relative to baseline in 85 (52.8% of 161 men (Group 1, whereas it had improved (∆PWVba < 0% in the remaining 76 men (47.2% (Group 2. During follow-up, we noticed 24 cardiovascular events in Group 1 and six events in Group 2 (P < 0.001. Cox proportional hazards analyses demonstrated that independent of conventional risk factor changes, absence of PWVba decrease was a predictor of MACE (RR 3.99; 95% CI:1.81–8.78; P = 0.004. The sensitivity of ∆PWVba was 80% and its specificity was 54%.Conclusions: This study demonstrates that an improvement in arterial stiffness may be obtained after six months of conventional therapy and clearly identifies patients who have a more favorable prognosis.Keywords: arterial stiffness, coronary artery disease, prognosis

  17. Antihypertensive treatment decreases arterial stiffness at night but not during the day. Results from the Hypertension in the Very Elderly Trial.

    OpenAIRE

    2016-01-01

    The main Hypertension in the Very Elderly Trial (HYVET) demonstrated a very marked reduction in cardiovascular events by treating hypertensive participants 80 years or older with a low dose, sustained release prescription of indapamide (indapamide SR, 1.5 mg) to which was added a low dose of an angiotensin converting enzyme inhibitor in two-thirds of cases (perindopril 2–4 mg). This report from the ambulatory blood pressure sub-study investigates whether changes in arterial stiffness and ambu...

  18. Relationship of daily arterial blood pressure monitoring readings and arterial stiffness profile in male patients with chronic obstructive pulmonary disease combined with arterial hypertension

    Directory of Open Access Journals (Sweden)

    Karoli N.A.

    2013-06-01

    Full Text Available The aim of the study was to determine correlation between arterial blood pressure daily rhythm and daily profile of arterial stiffness in male patients with chronic obstructive pulmonary disease (COPD and arterial hypertension. Materials et methods: Prospective investigation comprised 45 male patients with COPD and arterial hypertension. Individuals of 40 years younger and 80 years elder, patients with diabetes, stroke, angina pectoris, or heart infarction, vascular diseases, and exacerbation of chronic disease, bronchial and pulmonary diseases of other etiology were excluded from the analyses. Comparison group included 47 patients with essential arterial hypertension and without chronic respiratory diseases closely similar on general parameters with patients from main clinical series. Twenty-four-hour arterial blood pressure monitoring (ABPM and daily arterial stiffness monitoring were performed using BPLab® MnSDP-2 apparatus (Petr Telegin, Russian Federation. Results: Patients with COPD combined with arterial hypertension with raised arterial stiffness measures prevail over individuals in essential hypertension group. There is pathological alteration of the ABPM circadian rhythm and raised «Pressure load» values in raised arterial stiffness group. Conclusion: We found ABPM raised parameters in patients with COPD and arterial hypertension. It confirms necessity of ABPM in daily arterial stiffness assessment in patients with COPD.

  19. Arterial stiffness response to exercise in persons with and without Down syndrome.

    Science.gov (United States)

    Hu, Min; Yan, Huimin; Ranadive, Sushant M; Agiovlasitis, Stamatis; Fahs, Christopher A; Atiq, Muhammed; Atique, Nazia; Fernhall, Bo

    2013-10-01

    This study compared arterial stiffness and wave reflection at rest and following maximal exercise between individuals with and without Down syndrome (DS), and the influence of body mass index (BMI), peak oxygen uptake (VO2 peak) on changes in arterial stiffness. Twelve people with DS (26.6 ± 2.6 yr) and 15 healthy controls (26.2 ± 0.6 yr) completed this study. Intima-media thickness (IMT) and stiffness of common carotid artery was examined. Hemodynamic and arterial variables were measured before and 3-min after exercise. Persons with DS had higher BMI and lower VO 2 peak than controls. IMT did not differ between groups. At rest, carotid β stiffness was significantly higher in persons with DS (PObesity and particularly VO 2 peak influenced these findings. These results suggest impaired vascular function in people with DS.

  20. Arterial stiffness is inversely associated with a better running record in a full course marathon race

    OpenAIRE

    Jung, Su-Jeen; Park, Jae-Hyoung; Lee, Sewon

    2014-01-01

    [Purpose] Arterial stiffness is an independent predictor of cardiovascular risk and may contribute to reduced running capacity in humans. This study investigated the relationship between course record and arterial stiffness in marathoners who participated in the Seoul International Marathon in 2012. [Methods] A total of 30 amateur marathoners (Males n = 28, Females n = 2, mean age = 51.6 ± 8.3 years) were assessed before and after the marathon race. Brachial-ankle pulse wave velocity (ba-PWV)...

  1. Therapeutic modification of arterial stiffness:An update and comprehensive review

    Institute of Scientific and Technical Information of China (English)

    Ching-Fen; Wu; Pang-Yen; Liu; Tsung-Jui; Wu; Yuan; Hung; Shih-Ping; Yang; Gen-Min; Lin

    2015-01-01

    Arterial stiffness has been recognized as a marker of cardiovascular disease and associated with longterm worse clinical outcomes in several populations. Age, hypertension, smoking, and dyslipidemia, known as traditional vascular risk factors, as well as diabetes, obesity, and systemic inflammation lead to both atherosclerosis and arterial stiffness. Targeting multiple modifiable risk factors has become the main therapeutic strategy to improve arterial stiffness in patients at high cardiovascular risk. Additionally to life style modifications, long-term ω-3 fatty acids(fish oil) supplementation in diet may improve arterial stiffness in the population with hypertension or metabolic syndrome. Pharmacological treatment such as reninangiotensin-aldosterone system antagonists, metformin, and 3-hydroxy-3-methyl-glutaryl-Co A reductase inhibitors were useful in individuals with hypertension and diabetes. In obese population with obstructive sleep apnea, weight reduction, aerobic exercise, and continuous positive airway pressure treatment may also improve arterial stiffness. In the populations with chronic inflammatory disease such as rheumatoid arthritis, a use of antibodies against tumor necrosis factor-alpha could work effectively. Other therapeutic options such as renal sympathetic nerve denervation for patients with resistant hypertension are investigated in many ongoing clinical trials. Therefore our comprehensive review provides knowledge in detail regarding many aspects of pathogenesis, measurement, and management of arterial stiffness in several populations, which would be helpful for physicians to make clinical decision.

  2. [Left ventricular relaxation and ambulatory blood pressure in mild, untreated arterial hypertension].

    Science.gov (United States)

    Herpin, D; Raynier, P; Ciber, M; Amiel, A; Boutaud, P; Demange, J

    1989-03-01

    Twenty patients with mild, untreated arterial hypertension had ambulatory blood pressure recordings and a digitized echocardiographic study of the left ventricle with measurement of its mass (LVM) and of relaxation parameters. A significant correlation was found between LVM and ambulatory systolic pressure during daytime (r = 0.64; p less than 0.01; n = 20) and during 24 hours (r = 0.79; p less than 0.001; n = 16). One of the relaxation parameters studied, the time taken to reach maximal speed of left ventricular enlargement, was closely related to the diurnal diastolic blood pressure (r = 0.58; p less than 0.01; n = 20), whereas in this population with mild arterial blood pressure none of the parameters was related to the amount of increase of LVM. One may therefore consider the abnormalities of left ventricular relaxation as likely to appear at an early stage of arterial hypertension; their discovery may antedate that of LVM and confirm that the hypertensive disease is real. However, the methodological problems encountered with type of exploration ought to be stressed: left ventricular relaxation is a multifactorial phenomenon, and its echocardiographic approach is subject to many hazards.

  3. Obese children and adolescents have elevated nighttime blood pressure independent of insulin resistance and arterial stiffness

    DEFF Research Database (Denmark)

    Hvidt, Kristian N; Olsen, Michael H; Holm, Jens-Christian

    2014-01-01

    BACKGROUND: Insulin resistance has been related to elevated blood pressure (BP) in obese children and may adversely affect the vasculature by arterial stiffening. The objective was to investigate whether daytime and nighttime BP were elevated and related to insulin resistance and arterial stiffness...... in obese children and adolescents. METHODS: Ninety-two obese patients aged 10-18 years were compared with 49 healthy control individuals. Insulin resistance was measured as the homeostatic assessment model (HOMA), and arterial stiffness was measured as carotid-femoral pulse wave velocity (cfPWV). RESULTS...... analyses, the higher nighttime BP in the obese group was independent of logHOMA and cfPWV. CONCLUSIONS: Obese children had a higher nighttime BP when compared with the control group independently of insulin resistance and arterial stiffness. No relationship was found between insulin resistance and arterial...

  4. Whole-body vibration as a potential countermeasure for dynapenia and arterial stiffness

    Directory of Open Access Journals (Sweden)

    Arturo Figueroa

    2016-09-01

    Full Text Available Age-related decreases in muscle mass and strength are associated with decreased mobility, quality of life, and increased cardiovascular risk. Coupled with the prevalence of obesity, the risk of death becomes substantially greater. Resistance training (RT has a well-documented beneficial impact on muscle mass and strength in young and older adults, although the high-intensity needed to elicit these adaptations may have a detrimental or negligible impact on vascular function, specifically on arterial stiffness. Increased arterial stiffness is associated with systolic hypertension, left ventricular hypertrophy, and myocardial ischemia. Therefore, improvements of muscle strength and arterial function are important in older adults. Recently, whole-body vibration (WBV exercise, a novel modality of strength training, has shown to exhibit similar results on muscle strength as RT in a wide-variety of populations, with the greatest impact in elderly individuals with limited muscle function. Additionally, WBV training has been shown to have beneficial effects on vascular function by reducing arterial stiffness. This article reviews relevant publications reporting the effects of WBV on muscle strength and/or arterial stiffness. Findings from current studies suggest the use of WBV training as an alternative modality to traditional RT to countermeasure the age-related detriments in muscle strength and arterial stiffness in older adults.

  5. High-Dose versus Low-Dose Vitamin D Supplementation and Arterial Stiffness among Individuals with Prehypertension and Vitamin D Deficiency

    Directory of Open Access Journals (Sweden)

    Amanda Zaleski

    2015-01-01

    Full Text Available Introduction. Vitamin D deficiency is associated with the onset and progression of hypertension and cardiovascular disease (CVD. However, mechanisms underlying vitamin D deficiency-mediated increased risk of CVD remain unknown. We sought to examine the differential effect of high-dose versus low-dose vitamin D supplementation on markers of arterial stiffness among ~40 vitamin D deficient adults with prehypertension. Methods. Participants were randomized to high-dose (4000 IU/d versus low-dose (400 IU/d oral vitamin D3 for 6 months. 24 hr ambulatory blood pressure (BP, carotid-femoral pulse wave velocity, and pulse wave analyses were obtained at baseline and after 6 months of vitamin D supplementation. Results. There were no changes in resting BP or pulse wave velocity over 6 mo regardless of vitamin D dose (all p>0.202. High-dose vitamin D decreased augmentation index and pressure by 12.3 ± 5.3% (p=0.047 and 4.0 ± 1.5 mmHg (p=0.02, respectively. However, these decreases in arterial stiffness were not associated with increases in serum 25-hydroxyvitamin D over 6 mo (p=0.425. Conclusion. High-dose vitamin D supplementation appears to lower surrogate measures of arterial stiffness but not indices of central pulse wave velocity. Clinical Trial Registration. This trial is registered with www.clinicaltrials.gov (Unique Identifier: NCT01240512.

  6. Hypertension, Diabetes Type II, and Their Association: Role of Arterial Stiffness.

    Science.gov (United States)

    Smulyan, Harold; Lieber, Ari; Safar, Michel E

    2016-01-01

    In patients with both hypertension and type II diabetes, the systolic blood pressure (SBP) increases linearly with age, while that of diastolic blood pressure (DBP) declines curvilinearly as early as age 45, all suggesting the development of increased arterial stiffness. Increased stiffness is an important, independent, and significant risk predictor in subjects with hypertension and diabetes. In patients with both diseases, stiffness assessed at the same mean arterial pressure (MAP) was significantly higher in diabetic patients. Arterial stiffness is related to age, heart rate (HR), and MAP, but in diabetic patients, it also related to diabetes duration and insulin treatment (IT). In the metabolic syndrome (MetSyn), diabetes also acts on the small arteries through capillary rarefaction to reduce the effective length of the arterial tree, increases the reflected pulse wave and thus the pulse pressure (PP). These studies indicate that diabetes and hypertension additively contribute to increased pulsatility and suggest that any means to reduce stiffness would be beneficial in these conditions.

  7. Arterial stiffness is not increased in patients with short duration rheumatoid arthritis and ankylosing spondylitis.

    Science.gov (United States)

    Dzieża-Grudnik, Anna; Sulicka, Joanna; Strach, Magdalena; Siga, Olga; Klimek, Ewa; Korkosz, Mariusz; Grodzicki, Tomasz

    2017-04-01

    Patients with rheumatoid arthritis (RA) and ankylosing spondylitis (AS) have increased cardiovascular (CV) morbidity and mortality. Arterial stiffness is an independent predictor of CV events. The aim of the study was to assess arterial stiffness and inflammatory markers in patients with short duration chronic arthritis. We assessed carotid-femoral pulse wave velocity (PWV), augmentation index (AIx), traditional CV risk factors and inflammatory and endothelial markers in 71 chronic arthritis patients (RA and AS) and in 29 healthy controls. We did not find differences in PWV (for RA, AS and controls, respectively: 10 [8.8-10.9] versus 10.7 [9.1-11.8] versus 9.2 [8.3-11.4] m/s; p = .14) and AIx (for RA, AS and controls, respectively: 24.3 ± 11.5 versus 5.7 ± 12.4 versus 10 ± 12.8%; p = .22). Both groups of arthritis patients had active disease with significantly elevated inflammatory markers compared to controls. There were no correlations between endothelial and inflammatory markers and parameters of arterial stiffness in arthritis patients. When analyzing arthritis patients according to median of PVW, there were no significant differences in inflammatory and endothelial markers. We found that in patients with short duration active RA and AS arterial stiffness was not increased and furthermore, there was no association between markers of systemic inflammation and arterial stiffness.

  8. Comparison of arterial stiffness and microcirculatory changes following abdominal aortic aneurysm grafting.

    LENUS (Irish Health Repository)

    Moloney, M A

    2012-02-01

    BACKGOUND: Abdominal aortic aneurysm (AAA) surgery provides a unique opportunity to study the impact of arterial stiffness on central haemodynamics, reflected in augmentation index (AI). The aneurysmal aorta is significantly stiffer than undilated age-matched aorta. AIM: We investigated whether replacement of an aneurysmal aorta with a compliant graft would result in a decrease in AI, which would thus decrease myocardial workload parameters. METHODS: Patients undergoing elective open or endovascular AAA repair were assessed with applanation tonometry and laser fluximetry pre-operatively, immediately and long-term post-operatively. RESULTS: Replacement of a small segment of abnormal conduit vessel resulted in improvements in AI, demonstrating that arterial stiffness can be surgically manipulated. CONCLUSIONS: These results reflect a decreased myocardial workload post-aortic grafting. This decrease in AI is important from a risk factor management perspective, and arterial stiffness should become a further recognised and screened for risk factor in patients with known aneurysmal disease.

  9. Comparison of arterial stiffness and microcirculatory changes following abdominal aortic aneurysm grafting.

    LENUS (Irish Health Repository)

    Moloney, M A

    2010-11-11

    BACKGOUND: Abdominal aortic aneurysm (AAA) surgery provides a unique opportunity to study the impact of arterial stiffness on central haemodynamics, reflected in augmentation index (AI). The aneurysmal aorta is significantly stiffer than undilated age-matched aorta. AIM: We investigated whether replacement of an aneurysmal aorta with a compliant graft would result in a decrease in AI, which would thus decrease myocardial workload parameters. METHODS: Patients undergoing elective open or endovascular AAA repair were assessed with applanation tonometry and laser fluximetry pre-operatively, immediately and long-term post-operatively. RESULTS: Replacement of a small segment of abnormal conduit vessel resulted in improvements in AI, demonstrating that arterial stiffness can be surgically manipulated. CONCLUSIONS: These results reflect a decreased myocardial workload post-aortic grafting. This decrease in AI is important from a risk factor management perspective, and arterial stiffness should become a further recognised and screened for risk factor in patients with known aneurysmal disease.

  10. Relation of epicardial adipose tissue with arterial compliance and stiffness in patients with hypertension.

    Science.gov (United States)

    Korkmaz, Levent; Cirakoglu, Omer Faruk; Ağaç, Mustafa Tarik; Erkan, Hakan; Korkmaz, Ayca Ata; Acar, Zeydin; Kul, Selim; Hatem, Engin; Çelik, Şükrü

    2014-09-01

    The main aim of the present study was to investigate the association between epicardial adipose tissue (EAT) and arterial function in patients with asymptomatic hypertension. Patients with hypertension (n = 155) were enrolled consecutively. Patients with decreased arterial compliance (AC) and increased cardioankle vascular index (CAVI) had higher EAT values compared with those with normal AC and CAVI (6.23 ± 1.67 vs 4.91 ± 1.40, P arterial function in patients with asymptomatic hypertension. The link between EAT and arterial stiffness deserves further investigation.

  11. Hemoglobin A1c and arterial and ventricular stiffness in older adults.

    Directory of Open Access Journals (Sweden)

    Susan J Zieman

    Full Text Available OBJECTIVE: Arterial and ventricular stiffening are characteristics of diabetes and aging which confer significant morbidity and mortality; advanced glycation endproducts (AGE are implicated in this stiffening pathophysiology. We examined the association between HbA(1c, an AGE, with arterial and ventricular stiffness measures in older individuals without diabetes. RESEARCH DESIGN & METHODS: Baseline HbA(1c was measured in 830 participants free of diabetes defined by fasting glucose or medication use in the Cardiovascular Health Study, a population-based cohort study of adults aged ≥ 65 years. We performed cross-sectional analyses using baseline exam data including echocardiography, ankle and brachial blood pressure measurement, and carotid ultrasonography. We examined the adjusted associations between HbA(1c and multiple arterial and ventricular stiffness measures by linear regression models and compared these results to the association of fasting glucose (FG with like measures. RESULTS: HbA(1c was correlated with fasting and 2-hour postload glucose levels (r = 0.21; p<0.001 for both and positively associated with greater body-mass index and black race. In adjusted models, HbA(1c was not associated with any measure of arterial or ventricular stiffness, including pulse pressure (PP, carotid intima-media thickness, ankle-brachial index, end-arterial elastance, or left ventricular mass (LVM. FG levels were positively associated with systolic, diastolic and PP and LVM. CONCLUSIONS: In this sample of older adults without diabetes, HbA(1c was not associated with arterial or ventricular stiffness measures, whereas FG levels were. The role of AGE in arterial and ventricular stiffness in older adults may be better assessed using alternate AGE markers.

  12. Evaluation of carotid artery elasticity in patients with obstructive sleep apnea syndrome using quantitative arterial stiffness technique

    Institute of Scientific and Technical Information of China (English)

    俞飞虹

    2012-01-01

    Objective To explore the changes and clinical value of carotid elasticity index in patients with obstructive sleep apnea syndrome (OSAS) by quantitative arterial stiffness(OAS) technique. Methods Seventy-two OSAS patients were divided into 2 groups according to whether there was coexisting hypertension

  13. Relationship between sleep duration and arterial stiffness in a multi-ethnic population: The HELIUS study

    Science.gov (United States)

    Anujuo, Kenneth; Stronks, Karien; Snijder, Marieke B.; Jean-Louis, Girardin; van den Born, Bert-Jan; Peters, Ron J.; Agyemang, Charles

    2017-01-01

    We examined the relationship between sleep duration and arterial stiffness among a multi-ethnic cohort, and whether the associations differed among ethnic minority groups in the Netherlands. Data were derived from 10 994 participants (aged 18–71 years) of the Healthy Life in an Urban Setting (HELIUS) study. Self-reported sleep duration was categorized into: short (<7 h/night), healthy (7–8 h/night) and long (≥9 h/night). Arterial stiffness was assessed by duplicate pulse-wave velocity (PWV in m/s) measurements using the Arteriograph system. The association of sleep duration with PWV was analysed using linear regression (β) with 95% confidence interval (CI). Results showed that neither short nor long sleep was related to PWV in all ethnic groups, except for long sleep in Dutch men which was associated with higher PWV (indicating stiffer arteries) after adjustment for potential confounders (β = 0.67, 95%CI, 0.23–1.11). Our study showed no convincing evidence that sleep duration was related to arterial stiffness among various ethnic groups. The link between sleep duration and cardiovascular outcomes does not seem to operate through arterial stiffness. Further research is needed to consolidate these findings. PMID:27058653

  14. Lung function is associated with arterial stiffness in children.

    Directory of Open Access Journals (Sweden)

    Julian G Ayer

    Full Text Available BACKGROUND: In older adults, an independent association exists between impaired lung function and cardiovascular disease. This interaction might be related to the effects of aging and/or smoking. In order to explore possible childhood antecedents to this association, we hypothesized that decreased lung function and vascular stiffness might be related, in early life. OBJECTIVE: To determine the relationship between lung function and carotid augmentation index (AIx, a measure of vascular stiffness, in 8-year old children. METHODS: Data on brachial blood pressure, lung function (FEV(1, FVC, FEV(1/FVC, obtained by spirometry and carotid AIx75 (AIx standardised to an arbitrary heart rate of 75 beats per minute, obtained by applanation tonometry was available in 249 community-based 8-year old children. These healthy children had been subjects in a randomised controlled trial of two interventions (omega-3 fatty acid supplementation and house-dust mite avoidance to prevent asthma. Smoking in pregnancy and childhood environmental tobacco smoke (ETS exposure was prospectively collected by questionnaire. The association between lung function and carotid AIx75 was assessed in multivariate models that included sex, height, smoking status during pregnancy, ETS exposure and randomisation groups (house dust mite avoidance and dietary intervention as covariates. RESULTS: In the fully adjusted models, Carotid AIx75 was independently associated with FEV1 (standardised β = -0.17,b = -6.72, partial R(2 = .02, p = 0.03, FVC (standardised β = -0.29, b = -9.31, partial R(2 = 0.04, p<0.001 and FEV1/FVC (standardised β = .13, b = 18.4, partial R(2 = 0.02, p = 0.04. CONCLUSION: Lower lung volumes are associated with increased vascular stiffness at an early age. The interaction between lung function and vascular stiffness may thus represent more than just age-related alterations in both the pulmonary and vascular systems.

  15. Association between arterial stiffness and risk of coronary artery disease in a community-based population

    Institute of Scientific and Technical Information of China (English)

    Zhang Yun; Ye Ping; Luo Leiming; Bai Yongyi; Xu Ruyi; Xiao Wenkai; Liu Dejun

    2014-01-01

    Background Arterial stiffness is well known as an important risk factor for coronary artery disease.In this study,we aimed to investigate the association between carotid-ankle pulse wave velocity (caPWV) and risk of coronary artery disease (CAD),and the interaction between pulse wave velocity (PWV) and other potential risk factors of CAD.Methods A community-based cross-sectional study was conducted for subjects living in Beijing,China.We collected 213 subjects with coronary artery disease and 1 266 subjects without CAD between September 2007 and January 2009 in a community center of Beijing.A multivariate Logistic regression analysis was carried out to assess the odds ratios of factors related to CAD.Results We found CAD subjects were more likely to have a higher body massindex (BMI),fasting glucose,uric acid,low-density lipoprotein (LDL) cholesterol,high-sensitivity Creactive protein (hs-CRP),carotic-femoral pulse wave velocity (cfPWV) and caPWV (P <0.05),and CAD subjects had a significantly lower HDL cholesterol levels (P <0.05).Moreover,the proportion of hypertension in CAD subjects was significantly higher than non-CAD subjects.The multiple Logistic regression analysis showed that hypertension,higher uric acid,hs-CRP,cfPWV and caPWV levels significantly increased the risk of CAD,with ORs (Cl) of 1.47 (1.25-1.74),1.17 (1.01-1.26),1.35 (1.10-1.67),1.15 (1.09-1.19) and 1.07 (1.01-1.15),respectively.Higher HDL cholesterol was significantly associated with reduced risk of CAD,with ORs (CI) of 0.58 (0.40-0.83).In addition,cfPWV had significant association with age,hypertension,LDL cholesterol,with Pearson's coefficients of 0.166,0.074,and 0.030,respectively.Conclusions cfPWV and caPWV are independently associated with significant CAD,and cfPWV has significant correlation with age and hypertension.cfPWV and caPWV may be used as a practical tool for predicting the risk of CAD.

  16. Effects of weight loss and insulin reduction on arterial stiffness in the SAVE trial

    Directory of Open Access Journals (Sweden)

    Hughes Timothy M

    2012-09-01

    Full Text Available Abstract Background Chronic arterial stiffness contributes to the negative health effects of obesity and insulin resistance, which include hypertension, stroke, and increased cardiovascular and all-cause mortality. Weight loss and improved insulin sensitivity are individually associated with improved central arterial stiffness; however, their combined effects on arterial stiffness are poorly understood. The purpose of this study was to determine how insulin levels modify the improvements in arterial stiffness seen with weight loss in overweight and obese young adults. Methods To assess the effects of weight loss and decreased fasting insulin on vascular stiffness, we studied 339 participants in the Slow the Adverse Effects of Vascular Aging (SAVE trial. At study entry, the participants were aged 20–45, normotensive, non-diabetic, and had a body-mass index of 25–39.9 kg/m2. Measures of pulse wave velocity (PWV in the central (carotid-femoral (cfPWV, peripheral (femoral-ankle (faPWV, and mixed (brachial-ankle (baPWV vascular beds were collected at baseline and 6 months. The effects of 6-month change in weight and insulin on measures of PWV were estimated using multivariate regression. Results After adjustment for baseline risk factors and change in systolic blood pressure, 6-month weight loss and 6-month change in fasting insulin independently predicted improvement in baPWV but not faPWV or cfPWV. There was a significant interaction between 6-month weight change and change in fasting insulin when predicting changes in baPWV (p baPWV. Conclusions Young adults with excess weight who both lower their insulin levels and lose weight see the greatest improvement in vascular stiffness. This improvement in vascular stiffness with weight loss and insulin declines may occur throughout the vasculature and may not be limited to individual vascular beds. Trial registration NCT00366990

  17. Relationships between use of statins and arterial stiffness in normotensive and hypertensive patients with coronary artery disease

    Institute of Scientific and Technical Information of China (English)

    WANG Zhi-guang; CHEN Bing-wei; L(U) Na-qiang; CHENG Yan-mei; DANG Ai-min

    2013-01-01

    Background Statins improve arterial stiffness in patients with coronary artery disease (CAD).Hypertension is a predominant contributor of arterial stiffening.However,the influence of hypertension on the effect of statins for improving arterial stiffness in CAD patients has seldom been investigated.Therefore,in this study,we investigated the relationships between statin use and arterial stiffness in normotensive and hypertensive CAD patients.Methods Brachial-ankle pulse wave velocity (ba-PWV) was measured in 437 patients,including 220 hypertensive CAD patients (121 used statins,99 did not) and 217 normotensive CAD patients (105 used statins,112 did not).The normotensive and hypertensive CAD patients were matched according to age,sex,and body mass index (BMI).Results In the normotensive and hypertensive CAD patients,lipid profiles were significantly improved in the statin group compared with the non-statin group.No significant differences in the administered statins (i.e.,atorvastatin,simvastatin,rosuvastatin,and pravastatin) and statin therapy duration were found between normotensive and hypertensive CAD patients (all P>0.05).No significant correlation of ba-PWV and statin therapy duration was found in all CAD patients,normotensive CAD patients,or hypertensive CAD patients (all P>0.05).ba-PWV in the statin group was significantly lower than that in the non-statin group in normotensive CAD patients ((1331.68±167.52) cm/s vs.(1468.61±244.54) cm/s,P=0.002) but not in hypertensive CAD patients (P>0.05).In multiple linear regression analyses,statin therapy was significantly associated with ba-PWV after adjusting for confounding variables in normotensive CAD patients (P=0.018) but not in hypertensive CAD patients (P>0.05).Conclusions Statins may significantly improve arterial stiffness in CAD patients,and hypertension may probably influence the effectiveness of statin therapy in improving arterial stiffness in this population.Further studies are required to

  18. Does short-term whole-body vibration training affect arterial stiffness in chronic stroke? A preliminary study.

    Science.gov (United States)

    Yule, Christie E; Stoner, Lee; Hodges, Lynette D; Cochrane, Darryl J

    2016-03-01

    [Purpose] Previous studies have shown that stroke is associated with increased arterial stiffness that can be diminished by a program of physical activity. A novel exercise intervention, whole-body vibration (WBV), is reported to significantly improve arterial stiffness in healthy men and older sedentary adults. However, little is known about its efficacy in reducing arterial stiffness in chronic stroke. [Subjects and Methods] Six participants with chronic stroke were randomly assigned to 4 weeks of WBV training or control followed by cross-over after a 2-week washout period. WBV intervention consisted of 3 sessions of 5 min intermittent WBV per week for 4 weeks. Arterial stiffness (carotid arterial stiffness, pulse wave velocity [PWV], pulse and wave analysis [PWA]) were measured before/after each intervention. [Results] No significant improvements were reported with respect to carotid arterial stiffness, PWV, and PWA between WBV and control. However, carotid arterial stiffness showed a decrease over time following WBV compared to control, but this was not significant. [Conclusion] Three days/week for 4 weeks of WBV seems too short to elicit appropriate changes in arterial stiffness in chronic stroke. However, no adverse effects were reported, indicating that WBV is a safe and acceptable exercise modality for people with chronic stroke.

  19. Associations of metabolic variables with arterial stiffness in type 2 diabetes mellitus : focus on insulin sensitivity and postprandial triglyceridaemia

    NARCIS (Netherlands)

    van Dijk, RAJM; Bakker, SJL; Scheffer, PG; Heine, RJ; Stehouwer, CDA

    2003-01-01

    Background Type 2 diabetes mellitus is associated with an increased risk of atherothrombotic disease, which may in part be mediated through increased arterial stiffness. We investigated to what extent increased arterial stiffness is associated with cardiovascular risk factors that commonly cluster i

  20. Meta analysis of the changes of arterial stiffness of hypertension patients with CCB or ARB

    Institute of Scientific and Technical Information of China (English)

    张艺军

    2013-01-01

    Objective To evaluate the differences of the changes of arterial stiffness of hypertension patients with the treatment of calcium channel blocker(CCB) or angiotensin Ⅱ receptor blocker(ARB). Methods Based on the principles of evidence-based medicine,corresponding inclusion

  1. Etiology of End-Stage Renal Disease and Arterial Stiffness among Hemodialysis Patients

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    Balsam El Ghoul

    2017-01-01

    Full Text Available Background. Prior studies have demonstrated that conventional and emerging CV risk factors are associated with worsening arterial stiffness among end-stage renal disease (ESRD patients on hemodialysis. The present cross-sectional study evaluates the association between the etiology of ESRD and arterial stiffness among a cohort of hemodialysis patients. Methods. Etiology of ESRD was identified from patients’ medical records and classified as either vascular renal disease, diabetic nephropathy, nondiabetic glomerulopathy, tubular interstitial nephropathy, hereditary nephropathy, or ESRD of unconfirmed etiology. Results. A total of 82 subjects were enrolled. cfPWV was independently associated with the composite of either diabetic nephropathy or vascular renal disease (p=0.022, pulse pressure (p=0.001, and a history of CV events (p=0.025, but not history of hypertension or diabetes mellitus alone. The median cfPWVs in diabetic nephropathy and vascular renal disease were comparable and significantly higher than median cfPWVs in other etiologies of ESRD. Conclusion. The study suggests that the etiology of ESRD is independently associated with arterial stiffness among hemodialysis patients. Furthermore, arterial stiffness was higher among patients who developed renal sequelae of either diabetes mellitus or hypertension as compared with those who have a history of either diabetes mellitus or hypertension alone.

  2. Long-term pioglitazone therapy improves arterial stiffness in patients with type 2 diabetes mellitus.

    Science.gov (United States)

    Harashima, Keiichiro; Hayashi, Junichi; Miwa, Takashi; Tsunoda, Tooru

    2009-06-01

    Pioglitazone, a peroxisome proliferator-activated receptor gamma agonist, not only improves insulin resistance and glycemic control, but may also have additional beneficial vascular effects in patients with type 2 diabetes mellitus. We investigated whether pioglitazone had an influence on arterial stiffness, which is an independent predictor of cardiovascular events, in 204 patients with type 2 diabetes mellitus. A prospective, nonrandomized, open-label trial was performed that involved 41 patients treated with pioglitazone, 46 patients receiving sulfonylureas, 67 patients on insulin, and 50 patients on diet/exercise only. The follow-up period was 56 +/- 3 months. Arterial stiffness was evaluated by using the arterial stiffness index (ASI), which was based on analysis of the pulse wave amplitude pattern obtained during automated blood pressure measurement in the upper limb. The 4 groups had a similar baseline ASI, which was greater than the reference range in each group. Although antidiabetic therapies improved hemoglobin A(1c) and low-density lipoprotein cholesterol, ASI only decreased significantly in the pioglitazone group. Thus, pioglitazone improved abnormal arterial stiffness in patients with type 2 diabetes mellitus via a mechanism beyond the metabolic improvement. These findings may have important clinical implications in the use of pioglitazone in patients with type 2 diabetes mellitus.

  3. Differences in arterial stiffness at rest and after acute exercise between young men and women.

    Science.gov (United States)

    Doonan, Robert J; Mutter, Andrew; Egiziano, Giordano; Gomez, Yessica-Haydee; Daskalopoulou, Stella S

    2013-03-01

    There is controversy as to whether there are sex differences in arterial stiffness. Acute physical stress can elicit vascular abnormalities not present at rest. Our objective was to assess sex differences in arterial stiffness at rest and in response to acute physical stress. Healthy young men (n=67) and women (n=55) underwent pulse wave analysis and carotid-femoral pulse wave velocity measurements at rest and 2, 5, 10 and 15 min following an exercise test to exhaustion. At rest, aortic systolic, diastolic, pulse and mean pressures were all significantly higher in men as was aortic pulse pressure at 10 and 15 min post exercise and aortic systolic pressure at 15 min. Carotid-femoral pulse wave velocity was significantly higher in men (6.0±0.7 m s(-1) vs. 5.6±0.6 m s(-1), P=0.03) at rest and at all time points post exercise. Heart rate-adjusted augmentation index was significantly lower (-10.7±10.2% vs. -4.0±10.9, Psex differences in the arterial stiffness response to acute physical stress in young men and women. Although we were not able to elicit differences in vascular function after adjustment, which were not present at rest, we found that young men and women exhibit differences in arterial stiffness at rest and after acute physical stress.

  4. Acute effects of aerobic exercise intensity on arterial stiffness after glucose ingestion in young men.

    Science.gov (United States)

    Kobayashi, Ryota; Hashimoto, Yuto; Hatakeyama, Hiroyuki; Okamoto, Takanobu

    2016-10-18

    Arterial stiffness increases after glucose ingestion. Acute low- and moderate-intensity aerobic exercise decreases arterial stiffness. However, the acute effects of 30 min of cycling at low- and moderate-intensity [25% (LE trial) and 65% (ME trial) peak oxygen uptake, respectively] on arterial stiffness at 30, 60 and 120 min of a postexercise glucose ingestion. Ten healthy young men (age, 22·4 ± 0·5 years) performed LE and ME trials on separate days in a randomized controlled crossover fashion. Carotid-femoral (aortic) pulse wave velocity (PWV), femoral-ankle (leg) PWV, carotid augmentation index (AIx) and carotid blood pressure (BP) (applanation tonometry), brachial and ankle BP (oscillometric device), heart rate (HR) (electrocardiography), blood glucose (UV-hexokinase method) and blood insulin (CLEIA method) levels were measured at before (baseline) and at 30, 60 and 120 min after the 75-g OGTT. Leg PWV, ankle pulse pressure and BG levels significantly increased from baseline after the 75-g OGTT in the LE trial (P<0·05), but not in the ME trial. Insulin levels and HR significantly increased from baseline after the 75-g OGTT in both trials (P<0·05). Aortic PWV, carotid AIx, brachial BP and carotid BP did not change from baseline after the 75-g OGTT in both trials. The present findings indicate that aerobic exercise at moderate intensity before glucose ingestion suppresses increases leg arterial stiffness after glucose ingestion.

  5. Body composition, fitness score and arterial stiffness assesment in a chronic hemodialysis population

    Directory of Open Access Journals (Sweden)

    Adelina Mihăescu

    2011-12-01

    Full Text Available Patients undergoing long-term hemodialysis have a high risk of cardiovascular disease. Arterial stiffness is highly prevalent in this type of patients. The aim of our study was to analyse the relationship between body composition, blood chemistries and arterial stiffness in a poorly fit population of chronic hemodialysed patients. Patients and methods involved measuring body composition and fitness score by multifrequence bioimpedance with the body composition analyzer InBody720 and arterial stiffness by the measurement of aortic Pulse Wave Velocity (PWVao and Aortic Augmentation Index (Aix using an oscillometric method on 65 HD patients; measurements were made before a midweek dialysis session. Results: PWVao correlated significantly with weight (p=0.01, r2=1.14, body fat mass (p=0.007, r2=0.14, abdominal circumference (p=0.01, r2=0.12 and with fitness score (p=0.01, r2=0.11. Aix correlated with weight (p<0.05, r2=0.25, intracellular, extracellular- and total body water (p<0.05, r2=0.24 with body protein, soft lean mass, minerals, fat free mass and skeletal muscle mass (p<0.05, r2= 0.3 and with serum calcium (p=0.005, r2=0.2. Conclusions: Arterial stiffness is a common feature of the hemodialysed patients, significantly related to the blood calcium, fitness score and the body composition, especially fat body mass.

  6. Association between airway obstruction and peripheral arterial stiffness in elderly patients with chronic obstructive pulmonary disease

    Institute of Scientific and Technical Information of China (English)

    付志方

    2014-01-01

    Objective To evaluate the relationship between se-verity of airway obstruction and peripheral arterial stiffness in patients with chronic obstructive pulmonary disease(COPD).Methods 81 COPD patients[aged(78.32±6.98)yrs,73 males,8 females]from Jan2008 to Oct 2012 were enrolled in Geriatric Department

  7. Treatment with continuous subcutaneous insulin infusion is associated with lower arterial stiffness

    DEFF Research Database (Denmark)

    Vestergaard Rosenlund, Signe; Theilade, Simone; Hansen, Tine Willum;

    2014-01-01

    AIMS: To investigate the relationship between arterial stiffness and insulin treatment mode [continuous subcutaneous insulin infusion (CSII) versus multiple daily injections (MDI)] in type 1 diabetes patients. METHODS: Cross-sectional study, from 2009 to 2011, including 601 Caucasian type 1...

  8. Effect of passive heat stress on arterial stiffness in smokers versus non-smokers

    Science.gov (United States)

    Moyen, N. E.; Ganio, M. S.; Burchfield, J. M.; Tucker, M. A.; Gonzalez, M. A.; Dougherty, E. K.; Robinson, F. B.; Ridings, C. B.; Veilleux, J. C.

    2016-04-01

    In non-smokers, passive heat stress increases shear stress and vasodilation, decreasing arterial stiffness. Smokers, who reportedly have arterial dysfunction, may have similar improvements in arterial stiffness with passive heat stress. Therefore, we examined the effects of an acute bout of whole-body passive heat stress on arterial stiffness in smokers vs. non-smokers. Thirteen smokers (8.8 ± 5.5 [median = 6] cigarettes per day for >4 years) and 13 non-smokers matched for age, mass, height, and exercise habits (27 ± 8 years; 78.8 ± 15.4 kg; 177.6 ± 6.7 cm) were passively heated to 1.5 °C core temperature ( T C) increase. At baseline and each 0.5 °C T C increase, peripheral (pPWV) and central pulse wave velocity (cPWV) were measured via Doppler ultrasound. No differences existed between smokers and non-smokers for any variables (all p > 0.05), except cPWV slightly increased from baseline (526.7 ± 81.7 cm · s-1) to 1.5 °C Δ T C (579.7 ± 69.8 cm · s-1; p 0.05). Changes in cPWV and pPWV during heating correlated ( p < 0.05) with baseline PWV in smokers (cPWV: r = -0.59; pPWV: r = -0.62) and non-smokers (cPWV: r = -0.45; pPWV: r = -0.77). Independent of smoking status, baseline stiffness appears to mediate the magnitude of heating-induced changes in arterial stiffness.

  9. Roles of Arterial Stiffness and Blood Pressure in Hypertension-Associated Cognitive Decline in Healthy Adults.

    Science.gov (United States)

    Hajjar, Ihab; Goldstein, Felicia C; Martin, Greg S; Quyyumi, Arshed A

    2016-01-01

    Although there is strong evidence that hypertension leads to cognitive decline, especially in the executive domain, the relationship between blood pressure and cognition has been conflicted. Hypertension is characterized by blood pressure elevation and increased arterial stiffness. We aimed at investigating whether arterial stiffness would be superior to blood pressure in predicting cognitive decline and explaining the hypertension-executive decline association. A randomly selected asymptomatic population (n=591, age=49.2 years, 70% women, 27% black, and education=18 years) underwent annual vascular and cognitive assessments. Cognition was assessed using computerized versions commonly used cognitive tests, and principal component analysis was used for deriving cognitive scores for executive function, memory, and working memory. Arterial stiffness was measured by carotid-femoral pulse wave velocity (PWV). Higher PWV, but not blood pressure, was associated with a steeper decline in executive (P=0.0002), memory (P=0.05), and working memory (P=0.02) scores after adjusting for demographics, education, and baseline cognitive performance. This remained true after adjusting for hypertension. Hypertension was associated with greater decline in executive score (P=0.0029) and those with combined hypertension and elevated PWV (>7 m/s) had the greatest decline in executive score (P value hypertension×PWV=0.02). PWV explained the association between hypertension and executive function (P value for hypertension=0.0029 versus 0.24 when adjusting for PWV). In healthy adults, increased arterial stiffness is superior to blood pressure in predicting cognitive decline in all domains and in explaining the hypertension-executive function association. Arterial stiffness, especially in hypertension, may be a target in the prevention of cognitive decline.

  10. Combination treatment of rosuvastatin or atorvastatin, with regular exercise improves arterial wall stiffness in patients with coronary artery disease.

    Directory of Open Access Journals (Sweden)

    Kensuke Toyama

    Full Text Available OBJECTIVE: Statin- and exercise-therapy are both clinically beneficial by preventing cardiovascular events in patients with coronary artery disease (CAD. However, there is no information on the vascular effects of the combination of statins and exercise on arterial wall stiffness in CAD patients. METHODS: The present study is a sub-analysis of PRESET study that determined the effects of 20-week treatment with statins (rosuvastatin, n=14, atorvastatin, n=14 combined with regular exercise on arterial wall stiffness assessed by measurement of brachial and ankle pulse wave velocity (baPWV in CAD patients. RESULTS: The combination of statins and regular exercise significantly improved exercise capacity, lipid profile, including low- and high-density lipoprotein cholesterol, and high-sensitivity C-reactive protein (hs-CRP, baPWV (baseline: 1747 ± 355, at 20 weeks of treatment: 1627 ± 271 cm/s, p=0.008, and basophil count (baseline: 42 ± 32, 20 weeks: 26 ± 15 cells/µL, p=0.007, but had no effect on blood pressure (baseline: 125 ± 22, 20 weeks: 121 ± 16 mmHg. Changes in baPWV correlated significantly with changes in basophil count (r=0.488, p=0.008, but not with age, lipids profile, exercise capacity, or hs-CRP. CONCLUSION: In CAD patients, the combination treatment with statins and exercise resulted in significant amelioration of arterial wall stiffness, at least in part, through reduction of circulating basophils.

  11. Mean Platelet Volume and Arterial Stiffness – Clinical Relationship and Common Genetic Variability

    Science.gov (United States)

    Panova-Noeva, Marina; Arnold, Natalie; Hermanns, M. Iris; Prochaska, Jürgen H.; Schulz, Andreas; Spronk, Henri M.; Binder, Harald; Pfeiffer, Norbert; Beutel, Manfred; Blankenberg, Stefan; Zeller, Tanja; Lotz, Johannes; Münzel, Thomas; Lackner, Karl J.; ten Cate, Hugo; Wild, Philipp S.

    2017-01-01

    Vessel wall stiffening is an important clinical parameter, but it is unknown whether platelets, key elements in the pathogenesis of arterial thrombosis, are associated with arterial stiffness. The present studies sought to determine whether mean platelet volume (MPV), a potential marker of platelet activation, is linked to vascular elasticity as assessed by the augmentation index (AIx), in 15,010 individuals from the population-based Gutenberg Health Study. Multivariable analysis showed that MPV in both males (β 0.776; 95thCI [0.250;1.16]; p = 0.0024) and females (β 0.881[0.328;1.43]; p = 0.0018) is strongly associated with AIx. Individuals with MPV and AIx above the sex-specific medians had worse survival. Association analysis between MPV-related genetic variants and arterial stiffness identified four genetic variants in males and one in females related with AIx. Cox regression analysis for mortality identified one of these joint genetic variants close to ring finger protein 145 gene (RNF145, rs10076782) linked with increased mortality (hazard ratio 2.02; 95thCI [1.35;3.02]; p = 0.00061). Thus, these population-based data demonstrate a close relation between platelet volume as a potential marker of platelet activation and arterial stiffness in both sexes. Further research is warranted to further elucidate the mechanisms underlying larger platelets‘ role in arterial stiffening including the role of shared common genetics. PMID:28059166

  12. Affecting Factors of Arterial Stiffness in Living Related Kidney Transplant Recipients

    Directory of Open Access Journals (Sweden)

    Serpil Ergülü EŞMEN

    2011-05-01

    Full Text Available Arterial stiffness might be affected by several factors including recipient as well as donors. In this study, we aimed to evaluate arterial stiffness in living related kidney transplant recipients before and after transplantation. We enrolled 47 living related kidney recipients and pulse wave velocity (PWV was determined before and after transplantation. Donor renal arterial biopsy, recipient iliac artery samples were taken during the operation and PWV was also determined for the donors. Forty-seven patients completed the study. Post-transplantation follow-up duration was 18.5±5.7 months. Before transplantation, the mean PWV 8.1±1.4 m/sec and it was 7.5±2.0 m/sec after the transplantation (p=0.014. The patients were divided into two groups as with (30 patients and without (17 patients a PWV decrease. Recipient age, gender, CRP, PTH, lipids, and blood pressures were not significantly different between the groups. The recipient body mass index was higher in patients with a PWV decrease. Donor-related factors were not different between the groups. We found that blood pressure and LDL cholesterol levels in recipients were associated with a decrease in PWV after the transplantation. In conclusion, donor-related factors do not seem to have an impact on arterial stiffness in recipients. Pretransplant BMI and posttransplant blood pressure and LDL cholesterol levels were associated with a decrease in PWV.

  13. Increased arterial stiffness and extracellular matrix reorganization in intrauterine growth–restricted fetal sheep

    Science.gov (United States)

    Dodson, Reuben Blair; Rozance, Paul J.; Fleenor, Bradley S.; Petrash, Carson C.; Shoemaker, Lauren G.; Hunter, Kendall S.; Ferguson, Virginia L.

    2013-01-01

    BACKGROUND Fetal intrauterine growth restriction (IUGR) results in increased placental resistance to blood flow, fetal hypertension, and increased pulsatility stresses shown to lead to vascular remodeling. We tested our hypothesis that IUGR causes decreased compliance in the carotid and umbilical arteries due to altered extracellular matrix (ECM) composition and structure. METHODS A sheep model of placental insufficiency–induced IUGR (PI-IUGR) was created by exposure of the pregnant ewe to elevated ambient temperatures. Umbilical and carotid arteries from near-term fetuses were tested with pressure–diameter measurements to compare passive compliance in control and PI-IUGR tissues. ECM composition was measured via biochemical assay, and the organization was determined by using histology and second-harmonic generation imaging. RESULTS We found that PI-IUGR increased arterial stiffness with increased collagen engagement, or transition stretch. PI-IUGR carotid arteries exhibited increased collagen and elastin quantity, and PI-IUGR umbilical arteries exhibited increased sulfated glycosaminoglycans. Histomorphology showed altered collagen-to-elastin ratios with altered cellular proliferation. Increased stiffness indicates altered collagen-to-elastin ratios with less elastin contribution leading to increased collagen engagement. CONCLUSION Because vessel stiffness is a significant predictor in the development of hypertension, disrupted ECM deposition in IUGR provides a potential link between IUGR and adult hypertension. PMID:23154756

  14. Results of ambulatory arterial blood pressure monitoring in children with obesity

    Directory of Open Access Journals (Sweden)

    Faruk Öktem

    2010-12-01

    Full Text Available Objectives: The relationship between obesity and essential hypertension is well known. In this study, we aimed to evaluate ambulatory arterial blood pressure monitoring of obese and non-obese children who had similar demographic characteristics.Materials and methods: Seventy one children and adolescents (n=39 obesity, n=32 controls were studied. Blood pressure of the children were measured by 24 hour ambulatory blood pressure monitoring device.Results: Obese children had significantly higher mean blood pressure values (systolic 121.9±11.7 mmHg, diastolic 70.2±5.3 mmHg than control subjects (systolic 109.3±6.7 mmHg, diastolic 65.1±4.6 mmHg, p0.05. Blood pressure load was found to be increased in obese children compared to the controls (%13.6±12.9 and %2.6±3.4, respectively; p<0.05. Serum total cholesterol and LDL-cholesterol levels of obese children (181.1±33.4 and 131.1±23.1mg/dl were significantly higher than those of the controls (134.3±11.1 and 103.3±14.2 mg/dl, p<0.05.Conclusions: Obesity in children and adolescents should not be regarded as variations of normality, but as abnormality with an extremely high risk for the development of hypertension and hyperlipidemia in adulthood.

  15. Echocardiographic Assessment of Pulmonary Artery Systolic Pressure and Outcomes in Ambulatory Heart Failure Patients

    Science.gov (United States)

    Kalogeropoulos, Andreas P.; Siwamogsatham, Sarawut; Hayek, Salim; Li, Song; Deka, Anjan; Marti, Catherine N.; Georgiopoulou, Vasiliki V.; Butler, Javed

    2014-01-01

    Background Pulmonary hypertension (PH) in patients with heart failure (HF) is associated with worse outcomes and is rapidly being recognized as a therapeutic target. To facilitate pragmatic research efforts, data regarding the prognostic importance of noninvasively assessed pulmonary artery systolic pressure (PASP) in stable ambulatory patients with HF are needed. Methods and Results We examined the association between echocardiographic PASP and outcomes in 417 outpatients with HF (age, 54±13 years; 60.7% men; 50.4% whites; 24.9% with preserved ejection fraction). Median PASP was 36 mm Hg (interquartile range [IQR]: 29, 46). After a median follow‐up of 2.6 years (IQR: 1.7, 3.9) there were 72 major events (57 deaths; 9 urgent heart transplants; and 6 ventricular assist device implantations) and 431 hospitalizations for HF. In models adjusting for clinical risk factors and therapy, a 10‐mm Hg higher PASP was associated with 37% higher risk (95% CI: 18, 59; P<0.001) for major events, and 11% higher risk (95% CI: 1, 23; P=0.039) for major events or HF hospitalization. The threshold that maximized the likelihood ratio for both endpoints was 48 mm Hg; those with PASP ≥48 mm Hg (N=84; 20.1%) had an adjusted hazard ratio of 3.33 (95% CI: 1.96, 5.65; P<0.001) for major events and 1.47 (95% CI: 1.02, 2.11; P=0.037) for major events or HF hospitalization. Reduced right ventricular systolic function had independent prognostic utility over PASP for adverse outcomes. Right atrial pressure and transtricuspid gradient both contributed to risk. Conclusions Elevated PASP, determined by echocardiography, identifies ambulatory patients with HF at increased risk for adverse events. PMID:24492947

  16. Metabolic syndrome is associated with change in subclinical arterial stiffness - A community-based Taichung Community Health Study

    Directory of Open Access Journals (Sweden)

    Lin Wen-Yuan

    2011-10-01

    Full Text Available Abstract Background The aim of this study was to evaluate the effect of MetS on arterial stiffness in a longitudinal study. Methods Brachial-ankle pulse wave velocity (baPWV, a measurement interpreted as arterial stiffness, was measured in 1518 community-dwelling persons at baseline and re-examined within a mean follow-up period of 3 years. Multivariate linear regression with generalized estimating equations (GEE were used to examine the longitudinal relationship between MetS and its individual components and baPWV, while multivariate logistic regression with GEE was used to examine the longitudinal relationship between MetS and its individual components and the high risk group with arterial stiffness. Results Subjects with MetS showed significantly greater baPWV at the end point than those without MetS, after adjusting for age, gender, education, hypertension medication and mean arterial pressure (MAP. MetS was associated with the top quartile of baPWV (the high-risk group of arterial stiffness, adjusted odds ratio [95% confidence interval] 1.52 [1.21-1.90], and a significant linear trend of risk for the number of components of MetS was found (p for trend Conclusions MetS affects the subject's progression to arterial stiffness. Arterial stiffness increased as the number of MetS components increased. Management of MetS is important for preventing the progression to advanced arterial stiffness.

  17. Arterial Stiffness and Pulse Wave Reflection in Young Adult Heterozygous Sickle Cell Carriers

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    Tünzale Bayramoğlu

    2013-12-01

    Full Text Available OBJECTIVE: Pulse wave velocity (PWV and aortic augmentation index (AI are indicators of arterial stiffness. Pulse wave reflection and arterial stiffness are related to cardiovascular events and sickle cell disease. However, the effect of these parameters on the heterozygous sickle cell trait (HbAS is unknown. The aim of this study is to evaluate the arterial stiffness and wave reflection in young adult heterozygous sickle cell carriers. METHODS: We enrolled 40 volunteers (20 HbAS cases, 20 hemoglobin AA [HbAA] cases aged between 18 and 40 years. AI and PWV values were measured by arteriography. RESULTS: Aortic blood pressure, aortic AI, and brachial AI values were significantly higher in HbAS cases compared to the control group (HbAA (p=0.033, 0.011, and 0.011, respectively. A statistically significant positive correlation was found between aortic pulse wave velocity and mean arterial pressure, age, aortic AI, brachial AI, weight, and low-density lipoprotein levels (p=0.000, 0.017, 0.000, 0.000, 0.034, and 0.05, respectively in the whole study population. Aortic AI and age were also significantly correlated (p=0.026. In addition, a positive correlation between aortic PWV and systolic blood pressure and a positive correlation between aortic AI and mean arterial pressure (p=0.027 and 0.009, respectively were found in HbAS individuals. Our study reveals that mean arterial pressure and heart rate are independent determinants for the aortic AI. Mean arterial pressure and age are independent determinants for aortic PWV. CONCLUSION: Arterial stiffness measurement is an easy, cheap, and reliable method in the early diagnosis of cardiovascular disease in heterozygous sickle cell carriers. These results may depend on the amount of hemoglobin S in red blood cells. Further studies are required to investigate the blood pressure changes and its effects on arterial stiffness in order to explain the vascular aging mechanism in the HbAS trait population.

  18. Rationale and methodology of monitoring ambulatory blood pressure and arterial compliance in the Hypertension in the Very Elderly Trial

    OpenAIRE

    2006-01-01

    OBJECTIVE: This article describes the rationale and methodology for the monitoring of ambulatory blood pressure and arterial compliance in hypertensive patients aged 80 years and above. This is a side project of the Hypertension in the Very Elderly Trial. METHODS: The hypertension in the Very Elderly Trial is a multicentre, double-blind, randomized, placebo-controlled trial aiming to investigate the effect of active treatment on cardiovascular and other outcomes in hypertensive patients aged ...

  19. Effect of Simvastatin on Arterial Stiffness in Patients with Statin Myalgia

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    Kevin D. Ballard

    2015-01-01

    Full Text Available Statins reduce arterial stiffness but are also associated with mild muscle complaints. It is unclear whether individuals with muscle symptoms experience the same vascular benefit or whether statins affect striated and smooth muscle cells differently. We examined the effect of simvastatin treatment on arterial stiffness in patients who did versus those who did not exhibit muscle symptoms. Patients with a history of statin-related muscle complaints (n=115 completed an 8 wk randomized, double-blind, cross-over trial of daily simvastatin 20 mg and placebo. Serum lipids and pulse wave velocity (PWV were assessed before and after each treatment. Muscle symptoms with daily simvastatin treatment were reported by 38 patients (33%. Compared to baseline, central PWV decreased (P=0.01 following simvastatin treatment but not placebo (drug ∗ time interaction: P=0.047. Changes in central PWV with simvastatin treatment were not influenced by myalgia status or time on simvastatin (P≥0.15. Change in central PWV after simvastatin treatment was inversely correlated with age (r=-0.207, P=0.030, suggesting that advancing age is associated with enhanced statin-mediated arterial destiffening. In patients with a history of statin-related muscle complaints, the development of myalgia with short-term simvastatin treatment did not attenuate the improvement in arterial stiffness.

  20. Serum Uric Acid Level and Diverse Impacts on Regional Arterial Stiffness and Wave Reflection

    Directory of Open Access Journals (Sweden)

    Suyan Bian

    2012-08-01

    Full Text Available Background: Both increased arterial stiffness and hyperuricaemia are associated with elevated cardiovascular risks. Little is known about the relations of serum uric acid (UA level to regional arterial stiffness and wave reflection. The aim of the study was to investigate the gender-specific association of serum UA and indices of arterial function in a community-based investigation in China.Methods: Cross-sectional data from 2374 adults (mean age 58.24 years who underwent routine laboratory tests, regional pulse wave velocity (PWV and pulse wave analysis measurements were analyzed in a gender-specific manner. None of the participants had atherosclerotic cardiovascular disease, chronic renal failure, systemic inflammatory disease, gout, or were under treatment which would affect serum UA level.Results: Men had higher serum UA level than women. Subjects with hyperuricaemia had significantly higher carotid-ankle PWV in both genders (P< 0.05, and the carotid-femoral PWV (PWVc-f was higher in women (P< 0.001 while the augmentation index was marginally lower in men (P = 0.049. Multiple regression analysis showed that serum UA was an independent determinant only for PWVc-f in women (β = 0.104, P = 0.027 when adjusted for atherogenic confounders. No other independent relationship was found between UA level and other surrogates of arterial stiffness.Conclusions: Serum UA levels are associated with alterations in systemic arterial stiffness that differ in men and women. Women might be more susceptible to large vascular damage associated with hyperuricaemia.

  1. Children and Adolescent Obesity Associates with Pressure-Dependent and Age-Related Increase in Carotid and Femoral Arteries' Stiffness and Not in Brachial Artery, Indicative of Nonintrinsic Arterial Wall Alteration

    Science.gov (United States)

    García-Espinosa, Victoria; Curcio, Santiago; Castro, Juan Manuel; Arana, Maite; Giachetto, Gustavo; Chiesa, Pedro; Zócalo, Yanina

    2016-01-01

    Aim. To analyze if childhood obesity associates with changes in elastic, transitional, and/or muscular arteries' stiffness. Methods. 221 subjects (4–15 years, 92 females) were assigned to normal weight (NW, n = 137) or obesity (OB, n = 84) groups, considering their body mass index z-score. Age groups were defined: 4–8; 8–12; 12–15 years old. Carotid, femoral, and brachial artery local stiffness was determined through systodiastolic pressure-diameter and stress-strain relationships. To this end, arterial diameter and peripheral and aortic blood pressure (BP) levels and waveforms were recorded. Carotid-femoral, femoropedal, and carotid-radial pulse wave velocities were determined to evaluate aortic, lower-limb, and upper-limb regional arterial stiffness, respectively. Correlation analysis between stiffness parameters and BP was done. Results. Compared to NW, OB subjects showed higher peripheral and central BP and carotid and femoral stiffness, reaching statistical significance in subjects aged 12 and older. Arterial stiffness differences disappeared when levels were normalized for BP. There were no differences in intrinsic arterial wall stiffness (elastic modulus), BP stiffness relationships, and regional stiffness parameters. Conclusion. OB associates with BP-dependent and age-related increase in carotid and femoral (but not brachial) stiffness. Stiffness changes would not be explained by intrinsic arterial wall alterations but could be associated with the higher BP levels observed in obese children. PMID:27066273

  2. Arterial Structure and Function in Ambulatory Adolescents with Cerebral Palsy Are Not Different from Healthy Controls

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    Audra A. Martin

    2012-01-01

    Full Text Available Physical inactivity in youth with cerebral palsy (CP places them at increased risk of developing cardiovascular disease. The current study assessed indices of arterial health in adolescents with CP, classified as levels I-II of the Gross Motor Function Classification System (GMFCS (n=11, age 13.2±2.1 yr, in comparison to age- and sex-matched controls (n=11, age 12.4±2.3 yr. Groups were similar in anthropometric measurements, resting blood pressures, and heart rates. There were no group differences in brachial flow-mediated dilation (11.1±7.8 versus 6.1±3.6, carotid intima-media thickness (0.42±0.04 versus 0.41±0.03 mm, and distensibility (0.008±0.002 versus 0.008±0.002 mmHg or central (4.3±0.6 versus 4.1±0.9 m/s and peripheral pulse wave velocity (7.1±1.7 versus 7.6±1.1 m/s; CP versus healthy controls, respectively. Vigorous intensity physical activity (PA was lower in the CP group (CP: 38±80 min versus controls: 196±174 min; groups were similar in light and moderate intensity PA levels. Arterial health of ambulatory youth with CP is not different from a control group despite lower vigorous PA levels. Similar studies need to examine individuals with more pronounced mobility limitations (GMFCS level III–V.

  3. Application of a four-channel vibrometer system for detection of arterial stiffness

    Science.gov (United States)

    Campo, Adriaan; Waz, Adam; Dudzik, Grzegorz; Dirckx, Joris; Abramski, Krzysztof

    2016-06-01

    Cardiovascular diseases (CD) are the most important cause of death in the world and their prevalence is only rising. A significant aspect in the etiology of CD is the stiffening of the large arteries (arteriosclerosis) and plaque formation (atherosclerosis) in the common carotid artery (CCA) in the neck. As shown by increasing evidence, both conditions can be detected by assessing pulse wave velocity (PWV) in the CCA, and several approaches allow local detection of PWV, including ultrasound (US) and magnetic resonance imaging (MRI). In previous studies, laser Doppler vibrometry (LDV) was introduced as an approach to assess arterial stiffness. In the present work, a new, compact four-channel LDV system is used for PWV detection in four phantom arteries mimicking real life CCA conditions. The high sensitivity of the LDV system allowed PWV to be assessed, and even local changes in phantom architecture could be detected. This method has potential for cardiovascular screening, as it allows arteriosclerosis assessment and plaque detection.

  4. Short-term effects of nitrate-rich green leafy vegetables on blood pressure and arterial stiffness in individuals with high-normal blood pressure.

    Science.gov (United States)

    Bondonno, Catherine P; Liu, Alex H; Croft, Kevin D; Ward, Natalie C; Yang, Xingbin; Considine, Michael J; Puddey, Ian B; Woodman, Richard J; Hodgson, Jonathan M

    2014-12-01

    Evidence for a beneficial effect of dietary nitrate, through the nitrate-nitrite-NO pathway, on measures of cardiovascular function in healthy individuals is accumulating. It is less clear whether increased dietary nitrate intake from green leafy vegetables would have similar beneficial vascular effects in those at increased risk of developing hypertension. Our aim was to assess the effects of short-term regular consumption of increased nitrate from green leafy vegetables on blood pressure and arterial stiffness in individuals with high-normal blood pressure. Thirty-eight men and women ages 30-70 years with systolic blood pressure 120 to 139 mm Hg were recruited to a randomized controlled crossover trial. The effects of a 7-day high-nitrate diet intervention (increased nitrate intake by at least 300 mg/day from green leafy vegetables) were compared to a 7-day low-nitrate diet intervention. Outcome measures included pre- and postintervention salivary and plasma nitrate and nitrite concentrations; ambulatory, home, and office blood pressure; augmentation index; and carotid-femoral pulse wave velocity. The high-nitrate diet intervention resulted in at least a fourfold increase in salivary and plasma nitrate and nitrite (Pblood pressure and arterial stiffness were not different between the high-nitrate diet and the low-nitrate diet. Increasing dietary nitrate intake in those with high-normal blood pressure and at increased risk of hypertension may not be an effective short-term strategy to lower blood pressure.

  5. Arterial stiffness and enlargement in mild-to-moderate chronic kidney disease.

    Science.gov (United States)

    Briet, M; Bozec, E; Laurent, S; Fassot, C; London, G M; Jacquot, C; Froissart, M; Houillier, P; Boutouyrie, P

    2006-01-01

    Chronic kidney disease (CKD) is associated with an increased risk of cardiovascular morbidity and mortality. Arterial stiffness and remodeling have been well documented in patients with end-stage renal disease, but little is known about arterial phenotype in CKD patients with moderate reduction in glomerular filtration rate (GFR). In total, 95 patients (58+/-15 years, mean+/-s.d.) with CKD and GFR measured by renal clearance of (51)Cr-ethylenediaminetetraacetate were compared to 121 hypertensive patients without CKD (59+/-11 years), and 57 normotensive subjects (56+/-6 years). Common carotid artery diameter, intima-media thickness (IMT), distensibility, and Young's elastic modulus were noninvasively determined with a high-definition echotracking system. Patients with CKD had a significantly larger carotid internal diameter than in hypertensives and normotensives (6.32+/-1.05, 5.84+/-0.74, and 5.50+/-0.64 m x 10(-3), respectively; Pelastic modulus did not significantly differ between CKD and hypertensives; normotensives had significantly higher distensibility and lower elastic modulus than CKD and hypertensive patients. Carotid-femoral pulse wave velocity was significantly higher in CKD patients than in hypertensives and normotensives. In multivariate analyses either involving the entire population or restricted to CKD patients, GFR was independently and strongly related to carotid diameter and elastic modulus. Arterial enlargement and increased arterial stiffness occur in parallel with the decline in renal function in patients with mild-to-moderate CKD.

  6. Longitudinal perspective on the conundrum of central arterial stiffness, blood pressure, and aging.

    Science.gov (United States)

    Scuteri, Angelo; Morrell, Christopher H; Orrù, Marco; Strait, James B; Tarasov, Kirill V; Ferreli, Liana Anna Pina; Loi, Francesco; Pilia, Maria Grazia; Delitala, Alessandro; Spurgeon, Harold; Najjar, Samer S; AlGhatrif, Majd; Lakatta, Edward G

    2014-12-01

    The age-associated increase in arterial stiffness has long been considered to parallel or to cause the age-associated increase in blood pressure (BP). Yet, the rates at which pulse wave velocity (PWV), a measure of arterial stiffness, and BP trajectories change over time within individuals who differ by age and sex have not been assessed and compared. This study determined the evolution of BP and aortic PWV trajectories during a 9.4-year follow-up in >4000 community-dwelling men and women of 20 to 100 years of age at entry into the SardiNIA Study. Linear mixed effects model analyses revealed that PWV accelerates with time during the observation period, at about the same rate over the entire age range in both men and women. In men, the longitudinal rate at which BP changed over time, however, did not generally parallel that of PWV acceleration: at ages>40 years the rates of change in systolic BP (SBP) and pulse pressure (PP) increase plateaued and then declined so that SBP, itself, also declined at older ages, whereas PP plateaued. In women, SBP, diastolic BP, and mean BP increased at constant rates across all ages, producing an increasing rate of increase in PP. Therefore, increased aortic stiffness is implicated in the age-associated increase in SBP and PP. These findings indicate that PWV is not a surrogate for BP and that arterial properties other than arterial wall stiffness that vary by age and sex also modulate the BP trajectories during aging and lead to the dissociation of PWV, PP, and SBP trajectories in men.

  7. Carotid intima media thickness and arterial stiffness in children with acute rheumatic fever.

    Science.gov (United States)

    Çiftel, Murat; Yılmaz, Osman; Kardelen, Fırat; Kocabaş, Abdullah

    2014-01-01

    Acute rheumatic fever (ARF) and rheumatic heart disease (RHD) constitute important public health problems in developing countries. Inflammation is present both in the early and late stages of the diseases. Chronic inflammation is known to be associated with atherosclerosis. We hypothesize that subclinical atherosclerosis and arterial stiffness may increase due to the ongoing inflammation as well as the increased pulse pressure and left-ventricular systolic dysfunction in RHD. The purpose of the present study was to investigate carotid intima media thickness (CIMT) and carotid artery stiffness in patients with ARF. Forty patients in follow-up due to ARF in the age group of 7-16 years (disease duration 1-10 years) and 36 volunteered subjects with similar body mass index were included in the study. The subjects included in the present study were compared regarding M-mode echocardiographic parameters and CIMT as well as carotid arterial strain (CAS), carotid artery distensibility (CAD), beta stiffness index (βSI), and pressure-strain elasticity modulus (Ep) as carotid artery stiffness parameters. CIMT (0.52 ± 0.08 and 0.48 ± 0.07 mm, p = 0.01), βSI (5.29 ± 2.98 and 3.02 ± 1.30, p < 0.001), and Ep (426.53 ± 210.50 and 254.44 ± 104.69 p < 0.001) were increased, whereas CAS (0.11 ± 0.01 and 0.19 ± 0.09, p < 0.001) and CAD (10.27 ± 4.69 and 17.76 ± 14.41, p < 0.001) were decreased in patients with ARF compared with the control group. There was a positive correlation between pulse pressure and βSI (r = 0.25, p = 0.02) and Ep (r = 0.28, p = 0.01) in addition to a correlation between left atrial dilatation and CIMT (r = 0.55 p < 0.001) in patients with ARF. CIMT and carotid artery stiffness were increased in patients with ARF. Patients with ARF may have an increased risk of subclinical atherosclerosis and cardiovascular events.

  8. Association between arterial stiffness and left ventricular diastolic function in relation to gender and age

    Science.gov (United States)

    Kim, Hack-Lyoung; Lim, Woo-Hyun; Seo, Jae-Bin; Chung, Woo-Young; Kim, Sang-Hyun; Kim, Myung-A.; Zo, Joo-Hee

    2017-01-01

    Abstract Left ventricular (LV) diastolic dysfunction and subsequent overt heart failure are more prevalent in elderly women. Close interaction between arterial stiffness and LV morphology/function has been reported. The aim of this study was to investigate whether there is an age- and gender-dependent relationship between arterial stiffness and LV diastolic function. A total of 819 subjects (58.6 ± 13.3 years, 50.2% men) without structural heart disease (LV ejection fraction ≥50%) were retrospectively analyzed. All participants underwent transthoracic echocardiography and brachial-ankle pulse wave velocity (baPWV) measurement on the same day. The association of baPWV with septal e′ velocity and average E/e′ was assessed. In the total study subjects, baPWV was negatively correlated with septal e′ velocity (r = 0.383, P  0.05 for each). In conclusion, baPWV was independently associated with septal e′ velocity and E/e′ in elderly women but not in younger women or men. The results of this study provide additional evidence that increased arterial stiffness plays an important role in the development of heart failure with preserved ejection fraction as well as LV diastolic dysfunction in elderly women. PMID:28072727

  9. Adiponectin Genotype, Blood Pressures, and Arterial Stiffness: The Cardiometabolic Risk in Chinese (CRC) Study.

    Science.gov (United States)

    Liang, Jun; Qiu, Qinqin; Gong, Ying; Liu, Xuekui; Dou, Lianjun; Zou, Caiyan; Wang, Yu; Qi, Lu

    2015-05-01

    The authors examined whether the adiponectin gene (ADIPOQ) variant was associated with blood pressure and arterial stiffness in Chinese adults. A genome-wide association study of the adiponectin variant rs864265 in the ADIPOQ gene was genotyped in a total of 2364 participants. After adjustment for sex, age, body mass index (BMI), fasting glucose, and lipids, participants carrying the T allele of rs864265 showed a greater increase in carotid-femoral pulse wave velocity (cfPWV) and systolic blood pressure (SBP). Further adjustment for blood pressure did not appreciably change the association with cfPWV. The authors found significant interactions between rs864265 and BMI, waist circumference, body fat percentage, and SBP in relation to cfPWV (P for interaction = .035, .001, .003, .013, respectively). The T allele of rs864265 was associated with high blood pressure and arterial stiffness. BMI, body fat percentage, waist circumference, and SBP might modify the effects of genetic polymorphism on arterial stiffness.

  10. Association between peroxisome proliferator-activated receptor gene single nucleotide polymorphisms and arterial stiffness in adult Chinese population

    Institute of Scientific and Technical Information of China (English)

    许如意

    2013-01-01

    Objective To analyze the association between single nucleotide polymorphisms(SNPs) of peroxisome proliferator-activated receptor(PPAR)and arterial stiffness in adult Chinese population(>50 years).Methods

  11. Maternal arterial stiffness in women who subsequently develop pre-eclampsia.

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    Makrina D Savvidou

    Full Text Available BACKGROUND/OBJECTIVES: Pre-eclampsia (PE is associated with profound changes in the maternal cardiovascular system. The aim of the present study was to assess whether alterations in the maternal arterial stiffness precede the onset of PE in at risk women. METHODOLOGY/PRINCIPAL FINDINGS: This was a cross sectional study involving 70 pregnant women with normal and 70 women with abnormal uterine artery Doppler examination at 22-24 weeks of gestation. All women had their arterial stiffness (augmentation index and pulse wave velocity of the carotid-femoral and carotid-radial parts of the arterial tree assessed by applanation tonometry in the second trimester of pregnancy, at the time of the uterine artery Doppler imaging. Among the 140 women participating in the study 29 developed PE (PE group and 111 did not (non-PE group. Compared to the non-PE group, women that developed PE had higher central systolic (94.9 ± 8.6 mmHg vs 104.3 ± 11.1 mmHg; p  =  < 0.01 and diastolic (64.0 ± 6.0 vs 72.4 ± 9.1; p < 0.01 blood pressures. All the arterial stiffness indices were adjusted for possible confounders and expressed as multiples of the median (MoM of the non-PE group. The adjusted median augmentation index was similar between the two groups (p  =  0.84. The adjusted median pulse wave velocities were higher in the PE group compared to the non-PE group (carotid-femoral: 1.10 ± 0.14 MoMs vs 0.99 ± 0.11 MoMs; p < 0.01 and carotid-radial: 1.08 ± 0.12 MoMs vs 1.0 ± 0.11 MoMs; p < 0.01. CONCLUSIONS/SIGNIFICANCE: Increased maternal arterial stiffness, as assessed by pulse wave velocity, predates the development of PE in at risk women.

  12. Arterial stiffness and endothelial dysfunction independently and synergistically predict cardiovascular and renal outcome in patients with type 1 diabetes

    DEFF Research Database (Denmark)

    Theilade, S; Lajer, Maria Stenkil; Jorsal, Anders;

    2012-01-01

    To evaluate whether pulse pressure alone or with placental growth factor as estimates of arterial stiffness and endothelial dysfunction, predicts mortality, cardiovascular disease and progression to end-stage renal disease in patients with Type 1 diabetes.......To evaluate whether pulse pressure alone or with placental growth factor as estimates of arterial stiffness and endothelial dysfunction, predicts mortality, cardiovascular disease and progression to end-stage renal disease in patients with Type 1 diabetes....

  13. Circulating vascular progenitor cells and central arterial stiffness in polycystic ovary syndrome.

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    Cecile Dessapt-Baradez

    Full Text Available OBJECTIVE: Subjects with Polycystic ovarian syndrome (PCOS are at increased risk of Type 2 diabetes mellitus (T2DM. The mechanism of this enhanced risk is unclear. Circulating vascular progenitor cells (VPC are immature bone marrow derived cells capable of differentiating into mature endothelial cells. VPC number/function and central arterial stiffness predict cardio-metabolic disease in at-risk populations. DESIGN: We studied VPC and arterial stiffness measures in non-obese PCOS subjects as compared to age and body mass index (BMI matched healthy controls in a cross-sectional study. METHODS: Fourteen subjects with PCOS and 12 controls of similar age, BMI (all <30 kg/m(2 and metabolic profile were studied. VPC number and in vitro function were studied by flow cytometry and tube formation assays respectively. Augmentation index (AIx, a measure of central arterial stiffness, and central (aortic blood pressures (BP were measured by applanation tonometry. RESULTS: Subjects with PCOS had a reduced number, mean±SEM, of circulating CD34(+133(+ VPCs (317.5±51.0 vs. 558.3±101.2, p = 0.03 and impaired in vitro tube formation (completed tube area 1.0±0.06 vs. 1.2±0.05×10(6 µm(2 p = 0.02. PCOS subjects had significantly higher AIx (18.4±1.9% vs. 4.9±2.0% and this difference remained significant even after adjustments for age, BMI and smoking (p = 0.003 in multivariate analyses. Central systolic and pulse pressure were higher in PCOS subjects but these differences were not statistically significant after adjustment for age. Brachial systolic and pulse pressures were similar. VPC number/function and arterial stiffness or BP measures were not correlated. CONCLUSIONS: Non-obese PCOS is characterized by a reduced VPC number, impaired VPC function and increased central arterial stiffness. These changes in novel vascular risk markers may explain the enhanced risk of T2DM and CVD in PCOS.

  14. Correlation between arterial wall stiffness, N-terminal prohormone of brain natriuretic peptide, functional and structural myocardial abnormalities in patients with type 2 diabetes mellitus and cardiac autonomic neuropathy

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    Viktoriya Aleksandrovna Serhiyenko

    2013-12-01

    Full Text Available Aim. To assess arterial wall stiffness, plasma levels of of N-terminal prohormone of brain natriuretic peptide (NT-proBNP, as well as functional state and structure of the myocardium in patients with type 2 diabetes mellitus (T2DM and cardiac autonomic neuropathy (CAN.Materials and Methods. The study involved a total of 65 patients with T2DM. 12 had no evidence of cardiovascular disease (CVD or CAN, 14 were diagnosed with subclinical stage of CAN, 18 – with functional stage, and 21 – with organic stage. We measured aortic pulse wave velocity (PWV, aortic augmentation index (AIx, brachial artery AIx, ambulatory arterial stiffness index (AASI and plasma levels of NT-proBNP. Clinical examination included ECG, Holter monitoring, ambulatory BP measurement and echocardiography.Results. Patients with isolated T2DM showed a trend for increased vascular wall stiffness. PWV was increased in patients with subclinical stage of CAN. Aortic and brachial AIx, PWV and AASI were elevated in patients with functional stage of CAN, PWV being significantly higher vs. subclinical CAN subgroup. Organic stage was characterized by pathologically increased values of all primary parameters; PWV and AASI were significantly higher compared with other groups. Development and progression of CAN was accompanied by an increase in NT-proBNP plasma levels. Concentration of NT-proBNP was in direct correlation with left ventricular mass (LVM and PWV. PWV and LVM values also directly correlated between themselves.Conclusion. Development and progression of CAN in patients with T2DM is accompanied by an increase in vascular wall stiffness. The elevation of plasma NT-proBNP in patients with T2DM correlates with the development of CAN and is significantly and independently associated with an increase in LVM and PWV. Our data suggests the pathophysiological interconnection between metabolic, functional and structural myocardial abnormalities in patients with T2DM and CAN.

  15. Effects of dark chocolate and cocoa consumption on endothelial function and arterial stiffness in overweight adults.

    Science.gov (United States)

    West, Sheila G; McIntyre, Molly D; Piotrowski, Matthew J; Poupin, Nathalie; Miller, Debra L; Preston, Amy G; Wagner, Paul; Groves, Lisa F; Skulas-Ray, Ann C

    2014-02-01

    The consumption of cocoa and dark chocolate is associated with a lower risk of CVD, and improvements in endothelial function may mediate this relationship. Less is known about the effects of cocoa/chocolate on the augmentation index (AI), a measure of vascular stiffness and vascular tone in the peripheral arterioles. We enrolled thirty middle-aged, overweight adults in a randomised, placebo-controlled, 4-week, cross-over study. During the active treatment (cocoa) period, the participants consumed 37 g/d of dark chocolate and a sugar-free cocoa beverage (total cocoa = 22 g/d, total flavanols (TF) = 814 mg/d). Colour-matched controls included a low-flavanol chocolate bar and a cocoa-free beverage with no added sugar (TF = 3 mg/d). Treatments were matched for total fat, saturated fat, carbohydrates and protein. The cocoa treatment significantly increased the basal diameter and peak diameter of the brachial artery by 6% (+2 mm) and basal blood flow volume by 22%. Substantial decreases in the AI, a measure of arterial stiffness, were observed in only women. Flow-mediated dilation and the reactive hyperaemia index remained unchanged. The consumption of cocoa had no effect on fasting blood measures, while the control treatment increased fasting insulin concentration and insulin resistance (P= 0·01). Fasting blood pressure (BP) remained unchanged, although the acute consumption of cocoa increased resting BP by 4 mmHg. In summary, the high-flavanol cocoa and dark chocolate treatment was associated with enhanced vasodilation in both conduit and resistance arteries and was accompanied by significant reductions in arterial stiffness in women.

  16. Arterial stiffness in obese children: Role of adiposity and physical activity

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    Deepa S Pandit

    2014-01-01

    Full Text Available Objective: To explore association of adiposity and physical activity with arterial stiffness and to propose optimal waist circumference cutoffs, corresponding to 90 th percentile of NHANES (National Health and Nutrition Examination Survey for Indian children and adolescents. Materials and Methods: Data on weight, height, waist circumference, physical activity and right Carotid artery Intima-Media-Thickness (CIMT, pulse wave velocity (PWV, elasticity modulus (Ep, stiffness index(β, arterial compliance (AC were assessed in 250 children (72 normal-weight and 178 overweight/obese aged 6-17 years from Pune city, India. Body composition was measured using Dual energy X-ray absorptiometry. Results: Total, 37.1% normal-weight and 98.2% overweight/obese children had high adiposity (>95 th body fat percentile. Positive association of PWV and Ep (r = 0.5 also β(r = 0.25 with BMI (Body Mass Index, waist circumference and body fat (P < 0.05 was observed. Physical activity was inversely associated with PWV (r =-0.2, β(r =-0.13, Ep (r =-0.12 and positively with AC (r = 0.12 (P < 0.05. PWV significantly increased with increasing body fat for each tertile of physical activity (P < 0.05. Regression analysis revealed waist circumference, BMI, body fat and physical activity as independent associates for PWV after adjusting for age (P < 0.05. The cutoff of waist circumference yielding sensitivity and specificity for predicting the risk of high PWV was (−0.43, −0.44 for boys and girls with sensitivity in boys (girls of 78% (87% and specificity in boys (girls 51% (70%. The observed cutoffs are less than the NHANES-III cutoff values of waist circumference for 90 th percentiles according to age and sex. Conclusion: High adiposity and low physical activity are adversely related to arterial stiffness in Indian children.

  17. Arterial stiffness and wave reflections in patients with sickle cell disease.

    Science.gov (United States)

    Lemogoum, Daniel; Van Bortel, Luc; Najem, Boutaina; Dzudie, Anasthase; Teutcha, Charles; Madu, Ernest; Leeman, Marc; Degaute, Jean-Paul; van de Borne, Philippe

    2004-12-01

    We tested the hypothesis that lower blood pressure and increased vasodilatation reported in sickle cell disease (SCD) patients with hemoglobin SS genotype (SS) are translated by lower arterial stiffness determined by pulse wave velocity (PWV) and wave reflections assessed by augmentation index (AI). We enrolled 20 SS (8 females; 12 male) patients closely matched for age, gender, height, and body mass index to 20 subjects with hemoglobin AA genotype (AA). Carotid-femoral PWV (PWV(CF)) and carotid-radial PWV (PWV(CR)) were recorded with the Complior device. Aortic AI was derived from pressure wave analysis (SphygmocoR). PWV(CF) and PWV(CR) were lower in SS than in AA (4.5+/-0.7 m/s versus 6.9+/-0.9 m/s, P<0.0001 and 6.6+/-1.2 m/s versus 9.5+/-1.4 m/s, P<0.0001, respectively). AI was lower in SS than in AA (2+/-14% versus 11+/-8%, P=0.02). Multivariate analysis revealed that both PWV(CF) and PWV(CR) were negatively associated with hemoglobin SS type and positively related to mean arterial pressure (MAP), whereas AI was positively associated with MAP and total cholesterol (all P<0.0001). Multivariate analysis restricted to SS indicated a positive association between PWV(CF) and PWV(CR) with age but a negative association with MAP (R2=0.57 and 0.51, respectively, both P<0.001), whereas MAP and heart rate were independently associated with AI (R2=0.65, P<0.001). This study provides the first evidence that SCD is associated with both lower arterial stiffness and wave reflections. SS patients have a paradoxical negative association between PWV and MAP, suggesting that low MAP does not protect them against arterial stiffness impairment.

  18. Crises hipertensivas em portadores de hipertensão arterial em tratamento ambulatorial Crisis hipertensivas en portadores de hipertensión arterial en tratamiento ambulatorio Hypertensive crises in bearers of arterial hypertension in ambulatorial treatment

    Directory of Open Access Journals (Sweden)

    Nirla Gomes Guedes

    2005-06-01

    Full Text Available O presente estudo avaliou as características sociodemográficas e de adesão terapêutica de 27 portadores de hipertensão arterial em tratamento ambulatorial que apresentaram crises de urgências ou emergências hipertensivas e haviam sido atendidos em uma unidade de leito-dia e em uma unidade de emergência da cidade de Fortaleza-Ceará, no período de outubro de 2002 a maio de 2003. A maioria era mulher, com idade de 50 a 60 anos, pouca escolaridade, tempo de tratamento inferior a cinco anos e tempo de diagnóstico entre cinco e dez anos. O uso dos remédios foi o tratamento mais referido, seguido pela redução do consumo de sal e comparecimento às consultas. No entanto, o fato de comparecerem às consultas e receberem orientação parece não modificar o comportamento, uma vez que a maioria dos entrevistados não praticava exercícios físicos e demonstrava deficiência no conhecimento sobre a doença, atribuindo a elevação da pressão arterial a fatores emocionais.El presente estudio evaluó las características sociodemográficas y de adhesión terapéutica de 27 portadores de hipertensión arterial en tratamiento ambulatorio que presentaron crisis de urgencias o emergencias hipertensivas y habían sido atendidos en una unidad de internamiento diurno y en una unidad de emergencia de la ciudad de Fortaleza - Ceará, en el período de octubre del 2002 a mayo del 2003. La mayoría fue del sexo femenino, con edad de 50 a 60 años, poca escolaridad, tiempo de tratamiento inferior a cinco años y tiempo de diagnóstico entre cinco y diez años. El uso de los remedios fue el tratamiento más referido, seguido por la reducción del consumo de sal y asistencia a las consultas. Entre tanto, el hecho de asistir a las consultas y recibir orientación parece no modificar su comportamiento, pues la mayoría de los entrevistados no praticaba ejercicios físicos y demostraba falta de conocimiento sobre la enfermedad, atribuyendo la elevación de la

  19. Metabolomic profiles of lipid metabolism, arterial stiffness and hemodynamics in male coronary artery disease patients

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    Kaido Paapstel

    2016-06-01

    Conclusions: We demonstrated an independent association between the serum medium- and long-chain acylcarnitine profile and aortic stiffness for the CAD patients. In addition to the lipid-related classical CVD risk markers, the intermediates of lipid metabolism may serve as novel indicators for altered vascular function.

  20. The role of tissue renin angiotensin aldosterone system in the development of endothelial dysfunction and arterial stiffness

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    Annayya R Aroor

    2013-10-01

    Full Text Available Epidemiological studies support the notion that arterial stiffness is an independent predictor of adverse cardiovascular events contributing significantly to systolic hypertension, impaired ventricular-arterial coupling and diastolic dysfunction, impairment in myocardial oxygen supply and demand, and progression of kidney disease. Although arterial stiffness is associated with aging, it is accelerated in the presence of obesity and diabetes. The prevalence of arterial stiffness parallels the increase of obesity that is occurring in epidemic proportions and is partly driven by a sedentary life style and consumption of a high fructose, high salt and high fat western diet. Although the underlying mechanisms and mediators of arterial stiffness are not well understood, accumulating evidence supports the role of insulin resistance and endothelial dysfunction. The local tissue renin angiotensin aldosterone system (RAAS in the vascular tissue and immune cells and perivascular adipose tissue is recognized as an important element involved in endothelial dysfunction which contributes significantly to arterial stiffness. Activation of vascular RAAS is seen in humans and animal models of obesity and diabetes, and associated with enhanced oxidative stress and inflammation in the vascular tissue. The cross talk between angiotensin and aldosterone underscores the importance of mineralocorticoid receptors in modulation of insulin resistance, decreased bioavailability of nitric oxide, endothelial dysfunction and arterial stiffness. In addition, both innate and adaptive immunity are involved in this local tissue activation of RAAS. In this review we will attempt to present a unifying mechanism of how environmental and immunological factors are involved in this local tissue RAAS activation, and the role of this process in the development of endothelial dysfunction and arterial stiffness and targeting tissue RAAS activation.

  1. Association between aerobic exercise training effects of serum adropin level, arterial stiffness, and adiposity in obese elderly adults.

    Science.gov (United States)

    Fujie, Shumpei; Hasegawa, Natsuki; Kurihara, Toshiyuki; Sanada, Kiyoshi; Hamaoka, Takafumi; Iemitsu, Motoyuki

    2017-01-01

    Serum levels of adropin, which enhances endothelial cell release of nitric oxide (NO), are lower in obese patients. Although habitual aerobic exercise reduces arterial stiffness and adiposity, the relationship between these effects and circulating levels of adropin remains unclear. The purpose of this study was to determine if serum adropin level is associated with the effects of aerobic exercise training on arterial stiffness and adiposity in obese adults. In Experiment 1, we examined whether serum adropin levels are associated with cardiorespiratory fitness, carotid β-stiffness, plasma nitrite/nitrate (NOx) level, and abdominal visceral fat in 27 normal, 20 overweight, and 25 obese adults (age, 41-79 years). In Experiment 2, we examined the effects of an 8-week aerobic exercise training program on the relationship between serum adropin level and arterial stiffness or adiposity in 13 obese adults (age, 54-76 years). Serum adropin levels in normal, overweight, and obese adults negatively correlated with carotid β-stiffness and abdominal visceral fat, and positively correlated with plasma NOx level and cardiorespiratory fitness. After the 8-week exercise program, serum adropin levels in obese adults were elevated, and correlated with training-induced changes in carotid β-stiffness (r = -0.573, P exercise training-induced increase in serum adropin may be related to the training effects of arterial stiffness and adiposity in obese adults.

  2. Ambulatory instrument for monitoring indirect beat-to-beat blood pressure in superficial temporal artery using volume-compensation method.

    Science.gov (United States)

    Tanaka, S; Yamakoshi, K

    1996-11-01

    A portable instrument, based on a volume-compensation technique, is designed for ambulatory monitoring of indirect beat-to-beat blood pressure (BP) in the superficial temporal artery. The instrument consists of a small disc-type cuff and a portable unit carried by the subject. Several components are integrated in the cuff for applying counter-pressure to the artery, i.e. a reflectance-type photo-plethysmographic sensor for arterial volume detection, a pressure sensor for cuff pressure Pc measurement and a nozzle flapper-type- electro-pneumatic convertor for controlling Pc. The portable unit includes volume servo control circuitry and a microprocessor-based signal-processing and recording unit. This automatically performs all the necessary measurement procedures and stores into a memory IC element the processed systolic, mean and diastolic blood pressure data, together with pulse intervals on a beat-to-beat basis from the servo-controlled Pc (indirectly measured BP waveform). With this instrument, momentary changes in BP during ambulatory situations such as bicycle ergometer exercise and daily activities including motorway driving are successfully recorded. From the results of simultaneous measurement of the subject's posture changes, the effect of posture change on blood pressure, e.g. baroreceptor-cardiac reflex, is also clearly demonstrated.

  3. Testosterone suppression in men with prostate cancer leads to an increase in arterial stiffness and hyperinsulinaemia.

    Science.gov (United States)

    Dockery, Frances; Bulpitt, Christopher J; Agarwal, Sanjiv; Donaldson, Mandy; Rajkumar, Chakravarthi

    2003-02-01

    The role of androgens in cardiovascular disease is uncertain. We aimed to determine the vascular effects of androgen suppression in men with prostate cancer. Arterial stiffness (or 'compliance') was measured in 16 men (71+/-9 years, mean+/-S.D.) prior to, and 3 months after, complete androgen suppression with gonadotrophin-releasing hormone analogues as treatment for prostate cancer. Fifteen control men (70+/-7 years) also had arterial stiffness studies at baseline and 3 months later. Two measures of arterial stiffness were employed: systemic arterial compliance (SAC) was measured by simultaneous recording of aortic flow and carotid artery pressure ('area method'), and pulse wave velocities (PWVs) were recorded with the 'Complior' system. The 16 cases underwent glucose-tolerance and fasting-lipids tests on both visits. After 3 months of testosterone suppression, there was a significant fall in SAC, which was not seen in the controls [mean change+/-S.E.M., -0.26+/-0.09 a.c.u. (arbitrary compliance unit) in the cases versus +0.06+/-0.11 in the controls; P =0.03). Central, but not peripheral, PWVs tended to increase in the cases (mean change+/-S.E.M. for aorto-femoral PWV, +0.5+/-0.4 m/s for cases versus -0.3+/-0.3 m/s for controls; P =0.08). After testosterone suppression, fasting insulin levels increased from 6.89+/-4.84 m-units/l to 11.34+/-8.16 m-units/l (mean+/-S.D.), total cholesterol increased from 5.32+/-0.77 mmol/l to 5.71+/-0.82 mmol/l and high-density lipoprotein cholesterol increased from 1.05+/-0.24 mmol/l to 1.26+/-0.36 mmol/l; P change occurred in body-mass index, serum glucose, low-density lipoprotein cholesterol or triacylglycerol (triglyceride) levels. Our results indicate that loss of androgens in men leads to an increase in aortic stiffness and serum insulin levels, and may therefore adversely affect cardiovascular risk.

  4. Association of Insulin Resistance, Arterial Stiffness and Telomere Length in Adults Free of Cardiovascular Diseases.

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    Irina Strazhesko

    Full Text Available Chronic inflammation and oxidative stress might be considered the key mechanisms of aging. Insulin resistance (IR is a phenomenon related to inflammatory and oxidative stress. We tested the hypothesis that IR may be associated with cellular senescence, as measured by leukocyte telomere length (LTL, and arterial stiffness (core feature of arterial aging, as measured by carotid-femoral pulse wave velocity (c-f PWV.The study group included 303 subjects, mean age 51.8 ±13.3 years, free of known cardiovascular diseases and regular drug consumption. For each patient, blood pressure was measured, blood samples were available for biochemical parameters, and LTL was analyzed by real time q PCR. C-f PWV was measured with the help of SphygmoCor. SAS 9.1 was used for statistical analysis.Through multiple linear regression analysis, c-f PWV is independently and positively associated with age (p = 0.0001 and the homeostasis model assessment of insulin resistance (HOMA-IR; p = 0.0001 and independently negatively associated with LTL (p = 0.0378. HOMA-IR seems to have a stronger influence than SBP on arterial stiffness. In all subjects, age, HOMA-IR, LTL, and SBP predicted 32% of the variance in c-f PWV. LTL was inversely associated with HOMA-IR (p = 0.0001 and age (p = 0.0001. In all subjects, HOMA-IR, age, sex, and SBP predicted 16% of the variance in LTL.These data suggest that IR is associated with cell senescence and arterial aging and could, therefore, become the main target in preventing accelerated arterial aging, besides blood pressure control. Research in telomere biology may reveal new ways of estimating cardiovascular aging and risk.

  5. Early Biomarkers of Renal Damage in Relation to Arterial Stiffness and Inflammation in Male Coronary Artery Disease Patients

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    Kaido Paapstel

    2016-07-01

    Full Text Available Background/Aims: Plasma neutrophil gelatinase-associated lipocalin (NGAL, urinary liver-type fatty acid-binding protein (L-FABP and urinary kidney injury molecule-1 (KIM-1 have emerged as promising biomarkers for both acute and chronic kidney injury that also provide prognostic value for cardiovascular morbidity and mortality. Our aim was to evaluate their relationships with arterial stiffness and inflammation in coronary artery disease (CAD patients and in clinically healthy controls. Methods: We studied 52 patients with CAD (age 63.2 ± 9.2 years and 41 healthy controls (age 60.1 ± 7.2 years. Urinary L-FABP and KIM-1 as well as serum NGAL, adiponectin and resistin levels were measured using the enzyme-linked immunosorbent assay method. The technique of applanation tonometry was used for non-invasive pulse wave analysis and pulse wave velocity assessments. Results: Urinary L-FABP and KIM-1 were independent determinants of cf-PWV for the CAD patients (R2=0.584, Pr=0.31, P=0.028 only for the patients, while NGAL correlated with WBC count (rho=0.29, P=0.038; r=0.35, P=0.029 and resistin (rho=0.60, PConclusion: Our findings suggest that urinary L-FABP and KIM-1 may be independently associated with aortic stiffness in individuals with CAD.

  6. Sex differences in flexibility-arterial stiffness relationship and its application for diagnosis of arterial stiffening: a cross-sectional observational study.

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    Masato Nishiwaki

    Full Text Available Arterial stiffness might be related to trunk flexibility in middle-aged and older participants, but it is also affected by age, sex, and blood pressure. This cross-sectional observational study investigated whether trunk flexibility is related to arterial stiffness after considering the major confounding factors of age, sex, and blood pressure. We further investigated whether a simple diagnostic test of flexibility could be helpful to screen for increased arterial stiffening.According to age and sex, we assigned 1150 adults (male, n = 536; female, n = 614; age, 18-89 y to groups with either high- or poor-flexibility based on the sit-and-reach test. Arterial stiffness was assessed by cardio-ankle vascular index.In all categories of men and in older women, arterial stiffness was higher in poor-flexibility than in high-flexibility (P<0.05. This difference remained significant after normalizing arterial stiffness for confounding factors such as blood pressure, but it was not found among young and middle-aged women. Stepwise multiple-regression analysis also supported the notion of the sex differences in flexibility-arterial stiffness relationship. Receiver operating characteristic curve analysis revealed that cut-off values for sit-and-reach among men and women were 33.2 (area under the curve [AUC], 0.711; 95% confidence interval [CI], 0.666-0.756; sensitivity, 61.7%; specificity, 69.7% and 39.2 (AUC, 0.639; 95% CI, 0.592-0.686; sensitivity, 61.1%; specificity, 62.0% cm, respectively.Our results indicate that flexibility-arterial stiffness relationship is not affected by BP, which is a major confounding factor. In addition, sex differences are observed in this relationship; poor trunk flexibility increases arterial stiffness in young, middle-aged, and older men, whereas the relationship in women is found only in the elderly. Also, the sit-and-reach test can offer a simple method of predicting arterial stiffness at home or elsewhere.

  7. Effect of cigarette smoking on arterial stiffness re-interpreted using a structurally-based model

    DEFF Research Database (Denmark)

    Enevoldsen, Marie Sand; Humphrey, Jay D.; Lönn, Lars

    . The goal of this work was to use a structurally motivated nonlinear constitutive relation to quantify increased arterial stiffness based on available data. Specifically, we used a “four-fiber family model” that includes dominant effects of axial, circumferential, and symmetric-diagonal families of collagen...... parameters. The primary finding was that cigarette smoking induces significant increases in the material parameters describing the micromechanical properties of all four families of collagen fibers with increased duration of smoking. Additionally, there was a moderate increase in the material parameter...... describing the behaviour of the elastic fibers. These findings suggest that arterial stiffening in response to smoking is isotropic due to the changes in the material parameters seen in all fiber directions. Although changes are manifested in both elastic and collagen fibers, the predominant stiffening...

  8. Evaluation of 24-Hour Arterial Stiffness Indices and Central Hemodynamics in Healthy Normotensive Subjects versus Treated or Untreated Hypertensive Patients: A Feasibility Study

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    Stefano Omboni

    2015-01-01

    Full Text Available Objective. Central blood pressure (BP and vascular indices estimated noninvasively over the 24 hours were compared between normotensive volunteers and hypertensive patients by a pulse wave analysis of ambulatory blood pressure recordings. Methods. Digitalized waveforms obtained during each brachial oscillometric BP measurement were stored in the device memory and analyzed by the validated Vasotens technology. Averages for the 24 hours and for the awake and asleep subperiods were computed. Results. 142 normotensives and 661 hypertensives were evaluated. 24-hour central BP, pulse wave velocity (PWV, and augmentation index (AI were significantly higher in the hypertensive group than in the normotensive group (119.3 versus 105.6 mmHg for systolic BP, 75.6 versus 72.3 mmHg for diastolic BP, 10.3 versus 10.0 m/sec for aortic PWV, −9.7 versus −40.7% for peripheral AI, and 24.7 versus 11.0% for aortic AI, whereas reflected wave transit time (RWTT was significantly lower in hypertensive patients (126.6 versus 139.0 ms. After adjusting for confounding factors a statistically significant between-group difference was still observed for central BP, RWTT, and peripheral AI. All estimates displayed a typical circadian rhythm. Conclusions. Noninvasive assessment of 24-hour arterial stiffness and central hemodynamics in daily life dynamic conditions may help in assessing the arterial function impairment in hypertensive patients.

  9. Future Treatment of Hypertension: Shifting the Focus from Blood Pressure Lowering to Arterial Stiffness Modulation?

    Science.gov (United States)

    Fok, Henry; Cruickshank, J Kennedy

    2015-08-01

    Isolated systolic hypertension is the commonest form of hypertension from middle age onwards. Achieving target systolic blood pressure (BP) control remains difficult in everyday clinical practice and even under clinical trial conditions. Most antihypertensive medicines were designed to lower peripheral vascular resistance, which was considered the haemodynamic determinant of hypertension; most are effective in reducing steady but not pulsatile components of BP. Arterial stiffness, defined via aortic length-specific pulse wave velocity (PWV), is thought to be an important determinant of pulse pressure widening through its effects on the timing and amplitude of pressure wave reflection, and/or the aorta's Windkessel function, or its excess 'reservoir' pressure. Whereas pulse pressure is neither an independent nor consistent cardiovascular risk factor, particularly below the age of about 60 years, PWV has become the most powerful predictor of cardiovascular outcomes including mortality, independent of systolic, pulse, mean or other BP components. PWV is therefore a more direct target for treatment. This review addresses the potential therapeutic options for targeting arterial stiffness and the role of pulse pressure.

  10. Differential effects of nebivolol and metoprolol on arterial stiffness, circulating progenitor cells, and oxidative stress.

    Science.gov (United States)

    Hayek, Salim S; Poole, Joseph C; Neuman, Robert; Morris, Alanna A; Khayata, Mohamed; Kavtaradze, Nino; Topel, Matthew L; Binongo, Jose G; Li, Qunna; Jones, Dean P; Waller, Edmund K; Quyyumi, Arshed A

    2015-03-01

    Unlike traditional beta receptor antagonists, nebivolol activates nitric oxide. We hypothesized that therapy with nebivolol compared with metoprolol would improve arterial stiffness, increase levels of circulating progenitor cells (PC), and decrease oxidative stress (OS). In a randomized, double-blind, cross-over study, 30 hypertensive subjects received either once daily nebivolol or metoprolol succinate for 3 months each. Pulse wave velocity and augmentation index were measured using tonometry. Flow cytometry was used to measure circulating PC. OS was measured as plasma aminothiols. Measurements were performed at baseline, and repeated at 3 and 6 months. No significant differences were present between the levels of OS, arterial stiffness, and PC numbers during treatment with metoprolol compared with nebivolol. In subgroup analyses of beta-blocker naïve subjects (n = 19), nebivolol reduced pulse wave velocity significantly compared with metoprolol (-1.4 ± 1.9 vs. -0.1 ± 2.2; P = .005). Both nebivolol and metoprolol increased circulating levels of CD34+/CD133 + PC similarly (P = .05), suggesting improved regenerative capacity.

  11. Obstructive sleep apnea is associated with increased arterial stiffness in severe obesity.

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    Seetho, Ian W; Parker, Robert J; Craig, Sonya; Duffy, Nick; Hardy, Kevin J; Wilding, John P H

    2014-12-01

    Obstructive sleep apnea is associated with obesity and metabolic syndrome, leading to greater cardiovascular risk. Severely obese patients with obstructive sleep apnea may still be at risk of adverse health outcomes, even without previous cardiovascular disease. Pulse wave analysis non-invasively measures peripheral pulse waveforms and derives measures of haemodynamic status, including arterial stiffness, augmentation pressure and subendocardial viability ratio. We hypothesized that the presence of obstructive sleep apnea in severe obesity, even in the absence of an antecedent history of cardiovascular disease, would affect measurements derived from pulse wave analysis. Seventy-two severely obese adult subjects [obstructive sleep apnea 47 (body mass index 42 ± 7 kg m(-2) ), without obstructive sleep apnea (non-OSA) 25 (body mass index 40 ± 5 kg m(-2) )] were characterised using anthropometric, respiratory and cardio-metabolic parameters. Groups were similar in age, body mass index and gender. More subjects with obstructive sleep apnea had metabolic syndrome [obstructive sleep apnea 60%, without obstructive sleep apnea (non-OSA) 12%]. Those with obstructive sleep apnea had greater arterial stiffness, augmentation pressure and decreased subendocardial viability ratio (all P cardiovascular risk independently of metabolic abnormalities. The presence of obstructive sleep apnea in severe obesity identifies a group at high cardiovascular risk; clinicians should ensure that risk factors are managed appropriately in this group whether or not treatment of obstructive sleep apnea is offered or accepted by patients.

  12. Effect of Cardio-Metabolic Risk Factors Clustering with or without Arterial Hypertension on Arterial Stiffness: A Narrative Review

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    Vasilios G. Athyros

    2013-11-01

    Full Text Available The clustering of cardio-metabolic risk factors, either when called metabolic syndrome (MetS or not, substantially increases the risk of cardiovascular disease (CVD and causes mortality. One of the possible mechanisms for this clustering's adverse effect is an increase in arterial stiffness (AS, and in high central aortic blood pressure (CABP, which are significant and independent CVD risk factors. Arterial hypertension was connected to AS long ago; however, other MetS components (obesity, dyslipidaemia, dysglycaemia or MetS associated abnormalities not included in MetS diagnostic criteria (renal dysfunction, hyperuricaemia, hypercoaglutability, menopause, non alcoholic fatty liver disease, and obstructive sleep apnea have been implicated too. We discuss the evidence connecting these cardio-metabolic risk factors, which negatively affect AS and finally increase CVD risk. Furthermore, we discuss the impact of possible lifestyle and pharmacological interventions on all these cardio-metabolic risk factors, in an effort to reduce CVD risk and identify features that should be taken into consideration when treating MetS patients with or without arterial hypertension.

  13. Plasma homocysteine is associated with aortic arterial stiffness but not wave reflection in Chinese hypertensive subjects.

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    Wenkai Xiao

    Full Text Available OBJECTIVE: Elevated plasma total homocysteine (tHcy acts synergistically with hypertension to exert a multiplicative effect on cardiovascular diseases risk. The aim of this study was to determine the relationship between tHcy concentration and blood pressure, and to evaluate the role of plasma tHcy in arterial stiffness and wave reflection in hypertension. METHODS: In this cross-sectional study, a community-based sample of 1680 subjects (mean age 61.6 years was classified into four groups according to tHcy level (<21.6 vs. ≥ 21.6 µmol/l and blood pressure (hypertensive vs. normotensive. Levels of plasma tHcy and other biochemical parameters (e.g., lipids, glucose were determined. Central arterial blood pressure, reflected pressure wave, and carotid-femoral pulse wave velocity (cf-PWV were assessed by tonometry within 2 days of obtaining the blood specimen. RESULTS: Neither peripheral nor central blood pressure differed according to tHcy levels in normotensive and hypertensive subjects. Differences in cf-PWV according to tHcy were observed only in hypertensive subjects; differences in cf-PWV in normotensive subjects were not significant after adjusting for confounding factors. Central augmentation index did not differ according to tHcy level in either normotensive or hypertensive subjects. Results of univariate analysis revealed significant correlations between blood pressure parameters and tHcy concentration only among normotensive subjects; however, these correlations were not significant in a partial correlation analysis. Results of multiple regression analysis showed that plasma tHcy levels were independently correlated with cf-PWV in hypertensive subjects (β = 0.713, P = 0.004. The independent relationship between tHcy and central augmentation index was not significant by further multiple analyses in normotensive or hypertensive individuals. CONCLUSIONS: Plasma tHcy level is strongly and independently correlated with arterial

  14. Association of arterial stiffness with coronary flow reserve in revascularized coronary artery disease patients

    Institute of Scientific and Technical Information of China (English)

    Vlassis Tritakis; Stavros Tzortzis; Ignatios Ikonomidis; Kleanthi Dima; Georgios Pavlidis; Paraskevi Trivilou; Ioannis Paraskevaidis; Giorgos Katsimaglis; John Parissis; John Lekakis

    2016-01-01

    AIM: To investigate the association of arterial wave reflection with coronary flow reserve(CFR) in coronary artery disease(CAD) patients after successful revascularization.METHODS: We assessed 70 patients with angiographically documented CAD who had undergone recent successful revascularization. We measured(1) reactive hyperemia index(RHI) using fingertip peripheral arterial tonometry(RH-PAT Endo-PAT);(2) carotid to femoral pulse wave velocity(PWVc-Complior);(3) augmentation index(AIx), the diastolic area(DAI%) and diastolic reflection area(DRA) of the central aortic pulse wave(Arteriograph);(4) CFR using Doppler echocardiography; and(5) blood levels of lipoprotein-phospholipase A2(LpPLA2).RESULTS: After adjustment for age, sex, blood pressure parameter, lipidemic, diabetic and smoking status, we found that coronary flow reserve was independently related to AIx(b =-0.38, r = 0.009), DAI(b = 0.36, P = 0.014), DRA(b = 0.39, P = 0.005) and RT(b =-0.29,P = 0.026). Additionally, patients with CFR < 2.5 had higher PWVc(11.6 ± 2.3 vs 10.2 ± 1.4 m/s, P = 0.019), SBPc(139.1 ± 17.8 vs 125.2 ± 19.1 mm Hg, P = 0.026), AIx(38.2% ± 14.8% vs 29.4% ± 15.1%, P = 0.011) and lower RHI(1.26 ± 0.28 vs 1.50 ± 0.46, P = 0.012), DAI(44.3% ± 7.9% vs 53.9% ± 6.7%, P = 0.008), DRA(42.2 ± 9.6 vs 51.6 ± 11.4, P = 0.012) and Lp PLA2(268.1 ± 91.9 vs 199.5 ± 78.4 ng/m L, P = 0.002) compared with those with CFR ≥ 2.5. Elevated Lp PLA2 was related with reduced CFR(r =-0.33, P = 0.001), RHI(r =-0.37, P < 0.001) and DRA(r =-0.35, P = 0.001) as well as increased PWVc(r = 0.34, P = 0.012) and AIx(r = 0.34, P = 0.001). CONCLUSION: Abnormal arterial wave reflections are related with impaired coronary flow reserve despite successful revascularization in CAD patients. There is a common inflammatory link between impaired aortic wall properties, endothelial dysfunction and coronary flow impairment in CAD.

  15. Association between arterial stiffness, cerebral small vessel disease and cognitive impairment: a systematic review and meta-analysis

    Science.gov (United States)

    van Sloten, Thomas T; Protogerou, Athanase D; Henry, Ronald MA; Schram, Miranda T; Launer, Lenore J; Stehouwer, Coen DA

    2017-01-01

    Arterial stiffness may be a cause of cerebral small vessel disease and cognitive impairment. We therefore performed a systematic review and meta-analysis of studies on the association between stiffness, cerebral small vessel disease and cognitive impairment. For the associations between stiffness (i.e. carotid-femoral pulse wave velocity (cfPWV), brachial-ankle PWV (baPWV), carotid stiffness and pulse pressure) on the one hand and cerebral small vessel disease and cognitive impairment on the other, we identified 23 (n=15,666/22 cross-sectional/3 longitudinal) and 41 studies (n=57,671/30 cross-sectional/15 longitudinal), respectively. Pooled analyses of cross-sectional studies showed that greater stiffness was associated with markers of cerebral small vessel disease with odds ratios, per +1 SD, of 1.29 to 1.32 (P<.001). Studies on cognitive impairment could not be pooled due to large heterogeneity. Some (but not all) studies showed an association between greater stiffness and cognitive impairment, and the strength of this association was relatively weak. The present study supports the hypothesis that greater arterial stiffness is a contributor to microvascular brain disease. PMID:25827412

  16. Effect of cholesterol lowering on stiffness of aortic and femoral arterial walls in rabbits on a high fat diet

    Institute of Scientific and Technical Information of China (English)

    XUE Li; XU Wan-hai; XU Jin-zhi; ZHANG Tong; BI Hong-yuan; SHEN Bao-zhong

    2009-01-01

    Background Researches in arterial elasticity have increased over the past few years. We investigated the effects of simvastatin on vascular stiffness in fat fed rabbits by ultrasonography.Methods Thirty rabbits were assigned randomly to 3 groups: normal control group (A), the cholesterol group (B), simvastatin group (C: high fat diet for 4 weeks and high fat diet + simvastatin for further 4 weeks). Stiffness coefficient, pressure strain elastic modulus and velocity of pulse waves in abdominal aorta and femoral artery were measured by ultrasonographic echo tracking at the end of the 4th and the 8th weeks.Results At the end of the 4th week, stiffness coefficient, pressure strain elastic modulus and pulse wave velocity of femoral artery were significantly increased in group B compared with those in group A. Similarly, at the end of the 8th week, the same parameters of abdominal aorta were significantly increased in group B compared with those in group A. In contrast, stiffness coefficient, pressure strain elastic modulus and pulse wave velocity of femoral artery were significantly decreased in group C compared with those in group B, however, there was no significant difference in parameters of abdominal aorta between groups B and C.Conclusion Short term administration of simvastatin can improve the elasticity of femoral artery but not abdominal aorta.

  17. The effect of siesta in parameters of cardiac structure and in interpretation of ambulatory arterial blood pressure monitoring

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    Marco A.M. Gomes

    2000-04-01

    Full Text Available OBJECTIVE: To evaluate the influence of the siesta in ambulatory blood pressure (BP monitoring and in cardiac structure parameters. METHODS: 1940 ambulatory arterial blood pressure monitoring tests were analyzed (Spacelabs 90207, 15/15 minutes from 7:00 to 22:00 hours and 20/20 minutes from 22:01 to 6.59hours and 21% of the records indicated that the person had taken a siesta (263 woman, 52±14 years. The average duration of the siesta was 118±58 minutes. RESULTS: (average ± standard deviation The average of systolic/diastolic pressures during wakefulness, including the napping period, was less than the average for the period not including the siesta (138±16/85±11 vs 139±16/86±11 mmHg, p5%. CONCLUSION: The siesta influenced the heart structure parameters and from a statistical point of view the average of systolic and diastolic pressures and the respective pressure loads of the wakeful period.

  18. [Influence of treatment with olmesartan on ambulatory blood pressure monitoring parameters in patients with arterial hypertension].

    Science.gov (United States)

    Bregvadze, T R; Tseluĭko, V I; Mishchuk, N E

    2013-12-01

    Hypertension is the most common disease of the cardiovascular system. Active treatment of hypertension with adequate control of blood pressure (BP) can prevent complications, improve life quality and increase life expectancy. One of the interesting new antihypertensive agents, from the group of angiotensin receptor blockers is olmesartan. The obvious advantages of ambulatory blood pressure monitoring to traditional one-time measurements of BP make this method perspective for quality control of anti-hypertensive therapy. The aim of this study was to evaluate the influence of treatment with olmesartan on ambulatory blood pressure monitoring parameters in patients with hypertension. 38 out-patients with hypertension at the age of 25-84 years (mean 55,3±10,6) were studied. Patients received olmesartan 20 mg daily as monotherapy (20 patients (52,6%)) or in combination with other antihypertensive agents (18 patients (47,4%)). Treatment continued for 6 months. The complex examination included: measurement of office brachial BP, electrocardiography, echocardiography and ambulatory blood pressure monitoring (ABPM). As a result of treatment, office BP and diurnal BP, according to ABPM, significantly decreased; the favorable circadian BP profile dynamics were found: significantly less frequently observed lack of reduction in BP during night (daily index - non-dipper) - 18% vs. 64% (p treatment of hypertensive patients with olmesartan provides significant decline not only in office BP, but also in diurnal BP, normalizes BP of active and passive periods, also - daily index and reduces BP variability.

  19. Association of glomerular filtration rate with arterial stiffness in Chinese women with normal to mildly impaired renal function

    Institute of Scientific and Technical Information of China (English)

    Su-Yan Bian; Hong-Yang Guo; Ping Ye; Lei-Ming Luo; Hong-Mei Wu; Wen-Kai Xiao; Li-Ping Qi; He-Peng Yu; Liu-Fa Duan

    2012-01-01

    Objective Both decreased glomerular filtration rate (GFR) and arterial stiffness were considered as risk factors for atherosclerosis. Previous studies have suggested the association between central arterial stiffness and the degree of GFR loss. Whether decreased GFR contributes to peripheral artery stiffness remains controversial. Moreover, data analyzed from a cohort of Chinese women are rare. Our aim was to explore the relationship between GFR and regional arterial stiffness in Chinese women. Methods In this cross-sectional study, we randomly recruited 1131 adult women residents with GFR ≥ 60 mL/min per 1.73 m2 estimated by the Chinese Modification of Diet in Renal Disease equation from three large communities. Central and peripheral arterial stiffness were estimated simultaneously by measuring carotid-femoral pulse wave velocity (PWVcf) and carotid-radial PWV (PWVcr) using a validated automatic device. Augmentation Index at heart rate 75 beats/minutes (AIx-75) was measured by pulse wave analysis as a composite parameter reflecting both large and distal arterial properties. Results The mean estimated GFR (eGFR) of the study group was 100.05 ± 23.26 mL/minute per 1.73 m2. Subjects were grouped by tertiles of eGFR level. PWVcf and AIx-75 increased ongoing from the top to the bottom eGFR tertile, while the values of PWVcr were comparable. Both univariate Pearson correlations and multiple stepwise regression analyses showed that eGFR significantly correlated to PWVcf, but not to PWVcr and AIx-75. Conclusions In Chinese women with normal to mildly impaired renal function, decreased eGFR affected carotid-to-femoral rather than carotid-to-radial stiffening. This provides rational to conduct future prospective studies to investigate predictors of atherosclerosis in this population.

  20. Increased tea consumption is associated with decreased arterial stiffness in a Chinese population.

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    Chung-Hao Li

    Full Text Available BACKGROUND: Tea has attracted considerable attention for its potential cardioprotective effects. The primary chemical components of tea are thought to have a beneficial effect by reducing arterial stiffness. The objective of this study was to assess the association between tea consumption and brachial-ankle pulse wave velocity (baPWV in a relatively healthy Chinese population. METHODS: We enrolled 3,135 apparently healthy subjects from October 2006 to August 2009. Subjects taking medication for diabetes, hypertension, or hyperlipidemia, or with a history of cardiovascular disease, were excluded from the study. The subjects were categorized into three groups according to their tea-drinking habits: (1 none to low (n = 1615, defined as non-habitual tea drinkers, or drinking for 450 mL per day. Multiple logistic regression was used to determine whether different levels of consumption were independently associated with the highest quartile of baPWV values, defined as ≥1428.5 cm/s. RESULTS: Of the 3,135 subjects, 48.5% had drunk >150 mL of tea per day for at least 1 year. In multivariate regression analysis with adjustment for co-variables, including, age, sex, current smoking, alcohol use, habitual exercise, total cholesterol/high-density lipoprotein cholesterol (TC/HDL-C ratio >5, obesity, newly diagnosed hypertension and diabetes, subjects with high tea consumption had a decreased risk of highest quartile of baPWV by 22% (odds ratio = 0.78, 95% confidence interval = 0.62-0.98, p = 0.032, while subjects with moderate tea consumption did not (p = 0.742, as compared subjects with none to low tea consumption. CONCLUSIONS: High, but not moderate, habitual tea consumption may decrease arterial stiffness.

  1. Children and Adolescent Obesity Associates with Pressure-Dependent and Age-Related Increase in Carotid and Femoral Arteries’ Stiffness and Not in Brachial Artery, Indicative of Nonintrinsic Arterial Wall Alteration

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    Victoria García-Espinosa

    2016-01-01

    Full Text Available Aim. To analyze if childhood obesity associates with changes in elastic, transitional, and/or muscular arteries’ stiffness. Methods. 221 subjects (4–15 years, 92 females were assigned to normal weight (NW, n=137 or obesity (OB, n=84 groups, considering their body mass index z-score. Age groups were defined: 4–8; 8–12; 12–15 years old. Carotid, femoral, and brachial artery local stiffness was determined through systodiastolic pressure-diameter and stress-strain relationships. To this end, arterial diameter and peripheral and aortic blood pressure (BP levels and waveforms were recorded. Carotid-femoral, femoropedal, and carotid-radial pulse wave velocities were determined to evaluate aortic, lower-limb, and upper-limb regional arterial stiffness, respectively. Correlation analysis between stiffness parameters and BP was done. Results. Compared to NW, OB subjects showed higher peripheral and central BP and carotid and femoral stiffness, reaching statistical significance in subjects aged 12 and older. Arterial stiffness differences disappeared when levels were normalized for BP. There were no differences in intrinsic arterial wall stiffness (elastic modulus, BP stiffness relationships, and regional stiffness parameters. Conclusion. OB associates with BP-dependent and age-related increase in carotid and femoral (but not brachial stiffness. Stiffness changes would not be explained by intrinsic arterial wall alterations but could be associated with the higher BP levels observed in obese children.

  2. Stiffness of the large arteries in individuals with and without Down syndrome

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    Nunes Rodrigues A

    2011-06-01

    Full Text Available Anabel N Rodrigues1,2, Luan Cesar Coelho1, Washington LS Goncalves1,2, Sonia Alves Gouvea2, Maria José Rossi Vasconcellos1, Roberto S Cunha2, Glaucia R Abreu21School of Medicine, University Center of Espírito Santo, Colatina; 2Postgraduate Program in Physiological Sciences, Center for Health Sciences, Federal University of Espirito Santo, Vitória, BrazilBackground: Down syndrome is known to cause premature aging in several organ systems. However, it remains unclear whether this aging effect also affects the structure and function of the large arterial trunks. In this controlled study, the possibility of changes in the large arteries due to aging was evaluated in patients with Down syndrome.Methods: Eighty-two subjects of both genders were selected. The Down syndrome group had 41 active subjects consisting of 19 males and 22 females (mean age 21 ± 1, range 13–42 years without cardiovascular complications and who did not use vasoactive drugs. The control group consisted of 41 healthy individuals without trisomy 21 of the same gender and age as the Down syndrome group and who did not use vasoactive medication. Carotid–femoral pulse wave velocity was obtained as an index of aortic stiffness using an automatic noninvasive method.Results: Individuals with Down syndrome had significantly lower blood pressure than those in the control group. Systolic blood pressure for the Down syndrome group and control group was 106 ± 2 mmHg vs 117 ± 2 mmHg (P < 0.001, respectively; diastolic blood pressure was 66 ± 2 mmHg vs 77 ± 2 mmHg (P <0.001; and mean arterial pressure was 80 ± 1 mmHg vs 90 ± 1 mmHg (P < 0.001. Only age and systolic blood pressure were shown to correlate significantly with pulse wave velocity, but the slopes of the linear regression curves of these two variables showed no significant difference between the two study groups. Pulse wave velocity, which was initially significantly lower in the Down syndrome group (7.51 ± 0.14 m/s vs

  3. Effect of a tart cherry juice supplement on arterial stiffness and inflammation in healthy adults: a randomised controlled trial.

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    Lynn, Anthony; Mathew, Shilpa; Moore, Chris T; Russell, Jean; Robinson, Emma; Soumpasi, Vithleem; Barker, Margo E

    2014-06-01

    Tart cherries are a particularly rich source of anthocyanins. Evidence indicates that dietary intake of anthocyanins is inversely associated with arterial stiffness. We conducted an open-label randomised placebo controlled study to determine whether a tart cherry juice concentrate (Cherry Active) reduced arterial stiffness, inflammation and risk markers for cardiovascular disease in 47 healthy adults (30-50 years). Participants consumed 30 ml of cherry concentrate diluted to a volume of 250 ml with water or the same volume of an energy matched control drink daily for six weeks. Measurements were taken at baseline and at the end of the intervention. There was no effect of the intervention on arterial stiffness (P = 0.218), c-reactive protein (P = 0.220), systolic blood pressure (P = 0.163), diastolic blood pressure (P = 0.121), total cholesterol (P = 0.342) and high density lipoprotein cholesterol (P = 0.127). At the end of the intervention, plasma antioxidant capacity (measured as the ferric reducing ability of plasma (FRAP)) was significantly higher in the intervention group than the control group (P = 0.012). We conclude that a tart cherry juice concentrate rich in anthocyanins has no effect on arterial stiffness, c-reactive protein and risk markers for cardiovascular disease, but evokes a minor increase in antioxidant status in healthy adults.

  4. Association between Urine Creatinine Excretion and Arterial Stiffness in Chronic Kidney Disease: Data from the KNOW-CKD Study

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    Young Youl Hyun

    2016-08-01

    Full Text Available Background/Aims: Previous studies have shown that low muscle mass is associated with arterial stiffness, as measured by pulse wave velocity (PWV, in a population without chronic kidney disease (CKD. This link between low muscle mass and arterial stiffness may explain why patients with CKD have poor cardiovascular outcomes. However, the association between muscle mass and arterial stiffness in CKD patients is not well known. Methods: Between 2011 and 2013, 1,529 CKD patients were enrolled in the prospective Korean Cohort Study for Outcome in Patients With Chronic Kidney Disease (KNOW-CKD. We analyzed 888 participants from this cohort who underwent measurements of 24-hr urinary creatinine excretion (UCr and brachial-ankle PWV (baPWV at baseline examination. The mean of the right and left baPWV (mPWV was used as a marker of arterial stiffness. Results: The baPWV values varied according to the UCr quartile (1,630±412, 1,544±387, 1,527±282 and 1,406±246 for the 1st to 4th quartiles of UCr, respectively, PConclusion: Low muscle mass estimated by low UCr was associated high baPWV in pre-dialysis CKD patients in Korea. Further studies are needed to confirm the causal relationship between UCR and baPWV, and the role of muscle mass in the development of cardiovascular disease in CKD.

  5. Effects of sodium and potassium supplementation on blood pressure and arterial stiffness : a fully controlled dietary intervention study

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    Gijsbers, L.; Dower, J. I.; Mensink, M.; Siebelink, E.; Bakker, S. J. L.; Geleijnse, J. M.

    2015-01-01

    We performed a randomised, placebo-controlled, crossover study to examine the effects of sodium and potassium supplementation on blood pressure (BP) and arterial stiffness in untreated (pre) hypertensive individuals. During the study, subjects were on a fully controlled diet that was relatively low

  6. Effect of beta-1-blocker, nebivolol, on central aortic pressure and arterial stiffness in patients with essential hypertension

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    Radhika Soanker

    2012-01-01

    Conclusion: Nebivolol 5 mg demonstrated antihypertensive efficacy in patients with essential hypertension by reducing not only peripheral brachial pressures, but also significantly reducing central aortic pressures, augmentation index, and carotid femoral pulse wave velocity, which is the marker of arterial stiffness.

  7. Prevalence of arterial stiffness in North China, and associations with risk factors of cardiovascular disease: a community-based study

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    Wang Jin-Wen

    2012-12-01

    Full Text Available Abstract Background Brachial-ankle pulse wave velocity (baPWV, which reflects the stiffness of both central and peripheral muscular arteries, has been frequently used as a simple index for assessing arterial stiffness. The aim of the present study was to investigate the prevalence of arterial stiffness in North China based on baPWV measurements, and explore the associations between increased arterial stiffness and risk factors of cardiovascular diseases (CVD. Methods Twenty-three community populations were established in North China. For each participant, parameters for calculating baPWV, including blood pressures and pressure waveforms, were measured using a non-invasive automatic device. All participants were required to respond to an interviewer-led questionnaire including medical histories and demographic data, and to receive blood tests on biochemical indictors. Results A total of 2,852 participants were finally investigated. Among them, 1,201 people with low burden of CVD risk factors were chosen to be the healthy reference sample. The cut-off point of high baPWV was defined as age-specific 90th percentile of the reference sample. Thus, the prevalence of high baPWV was found to be 22.3% and 26.4% in men and women respectively. After adjusted for age, heart rate (HR, systolic blood pressure (SBP, fasting glucose level, and smoking were significantly associated with high baPWV in men; while level of serum total cholesterol (TC, HR, SBP, and diabetes were significantly associated with high baPWV in women. Conclusions Based on the age-specific cut-off points, the middle-aged population has a higher prevalence of high baPWV in North China. There exists a difference between men and women in terms of the potential risk factors associated with arterial stiffness.

  8. Association between arterial stiffness, disease activity and functional impairment in ankylosing spondylitis patients: a cross-sectional study.

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    Avram, Claudiu; Drăgoi, Răzvan Gabriel; Popoviciu, Horațiu; Drăgoi, Mihai; Avram, Adina; Amaricăi, Elena

    2016-08-01

    Cardiovascular risk is an important factor for increased morbidity and mortality in patients with ankylosing spondylitis. The aim of this study is to assess arterial stiffness in relation to the disease activity and functional limitation in patients with ankylosing spondylitis. Twenty-four patients (mean age 45.8 ± 11.7 years) suffering of ankylosing spondylitis (disease duration 11.1 ± 5.1 years) and 24 gender and age-matched healthy controls were included in the study. Clinical, biological, and functional status of ankylosing spondylitis patients was recorded. Arterial stiffness was assessed by measuring pulse wave velocity (PWV) and pulse wave analysis (PWA) was performed using applanation tonometry. We found significant differences between ankylosing spondylitis patients and healthy controls in regard to PWV (p = 0.047), aortic augmentation pressure-AP (p = 0.028), augmentation index-AIx (p = 0.038) and aortic augmentation index adjusted for heart rate-AIx75 (p = 0.011). PWV and AIx75 were significantly associated with the disease functioning score-BASFI (p = 0.012, r = 0.504; p = 0.041, r = 0.421). Aortic AP and augmentation indexes (AIx and AIx75) were all associated to ASDAS score (p = 0.028, r = 0.448; p = 0.005, r = 0.549; p = 0.025, r = 0.455). Our study showed that ankylosing spondylitis patients have a higher arterial stiffness than the age-matched controls, leading to an increased cardiovascular risk. We found that arterial stiffness is positively associated with disease activity and functional impairment. Chronic spondiloarthropaties should be screened for arterial stiffness, even in the absence of traditional cardiovascular risk factors, in order to benefit from primary prevention measures.

  9. Altered arterial stiffness and subendocardial viability ratio in young healthy light smokers after acute exercise.

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    Robert J Doonan

    Full Text Available BACKGROUND: Studies showed that long-standing smokers have stiffer arteries at rest. However, the effect of smoking on the ability of the vascular system to respond to increased demands (physical stress has not been studied. The purpose of this study was to estimate the effect of smoking on arterial stiffness and subendocardial viability ratio, at rest and after acute exercise in young healthy individuals. METHODS/RESULTS: Healthy light smokers (n = 24, pack-years = 2.9 and non-smokers (n = 53 underwent pulse wave analysis and carotid-femoral pulse wave velocity measurements at rest, and 2, 5, 10, and 15 minutes following an exercise test to exhaustion. Smokers were tested, 1 after 12h abstinence from smoking (chronic condition and 2 immediately after smoking one cigarette (acute condition. At rest, chronic smokers had higher augmentation index and lower aortic pulse pressure than non-smokers, while subendocardial viability ratio was not significantly different. Acute smoking increased resting augmentation index and decreased subendocardial viability ratio compared with non-smokers, and decreased subendocardial viability ratio compared with the chronic condition. After exercise, subendocardial viability ratio was lower, and augmentation index and aortic pulse pressure were higher in non-smokers than smokers in the chronic and acute conditions. cfPWV rate of recovery of was greater in non-smokers than chronic smokers after exercise. Non-smokers were also able to achieve higher workloads than smokers in both conditions. CONCLUSION: Chronic and acute smoking appears to diminish the vascular response to physical stress. This can be seen as an impaired 'vascular reserve' or a blunted ability of the blood vessels to accommodate the changes required to achieve higher workloads. These changes were noted before changes in arterial stiffness or subendocardial viability ratio occurred at rest. Even light smoking in young healthy individuals

  10. Assessment of Pulmonary Artery Stiffness of Repaired Congenital Heart Disease Patients

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    Lee, Namheon; Banerjee, Rajit; Taylor, Michael; Hor, Kan

    2012-10-01

    Surgical correction or palliation of congenital heart disease (CHD) often requires augmenting the main pulmonary artery (MPA) with non-native material or placing a cylindrical graft. The degree to which this intervention affects PA compliance is largely unknown. In this study, the MPA stiffness characteristics were assessed by its compliance, distensibility, and pressure-strain modulus. Coregistered velocity encoded phase-contrast MRI and cardiac catheterization data were available for a cohort of repaired CHD patients (n=8) and controls (n=3). All patients were repaired with either an RV-PA conduit or a RV outflow tract patch. We measured the MPA area change by MRI and MPA pressure during the cath. The measurements were taken through or just distal to the conduit. The MPA compliance and distensibility for the patients were significantly lower than the controls: compliance (9.8±10.8 vs 28.3±7.7mm^2/mmHg, p<0.05), distensibility (2.2±1.5 vs 6.6±2.1%Area change/mmHg, p=0.05). The patients had a significantly higher pressure-strain modulus (152.3±116.4mmHg, p<0.05) than the controls (35.8±10.6mmHg). The abnormally elevated PA stiffness due to the rigidity of the conduit or patch material may cause a compliance mismatch resulting in high stress levels contributing to the observed progressive PA dilatation. This may be a factor in the progressive RV dilatation seen in this cohort of repaired CHD patients.

  11. Association of arterial stiffness and electrocardiography-determined left ventricular hypertrophy with left ventricular diastolic dysfunction.

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    Po-Chao Hsu

    Full Text Available OBJECTIVES: Increased arterial stiffness is associated with left ventricular diastolic dysfunction (LVDD, but this association may be influenced by left ventricular (LV performance. Left ventricular hypertrophy (LVH is not only a significant determinant of LV performance, but is also correlated with LVDD. This study is designed to compare LV diastolic function among patients divided by brachial-ankle pulse wave velocity (baPWV and electrocardiography (ECG-determined LVH and to assess whether increased baPWV and ECG-determined LVH are independently associated with LVDD. METHODS: This cross-sectional study enrolled 270 patients and classified them into four groups according to the median value of baPWV and with/without ECG-determined LVH. The baPWV was measured using an ABI-form device. ECG-determined LVH was defined by Sokolow-Lyon criterion. LVDD was defined as impaired relaxation, pseudonormal, and restrictive mitral inflow patterns. Groups 1, 2, 3, and 4 were patients with lower baPWV and without ECG-determined LVH, lower baPWV but with ECG-determined LVH, higher baPWV but without ECG-determined LVH, and higher baPWV and with ECG-determined LVH respectively. RESULTS: Early diastolic mitral velocity (Ea was gradually decreased from group 1 to group 4 (p≦0.027. Patients in group 4 had the highest prevalence of LVDD (all p<0.001. After multivariate analysis, both baPWV and ECG-determined LVH were independent determinants of Ea (β = -0.02, P<0.001; β = -1.77, P<0.001 respectively and LVDD (odds ratio = 1.02, P = 0.011 and odds ratio = 3.53, P = 0.013 respectively. CONCLUSION: Our study showed the group with higher baPWV and ECG-determined LVH had the lowest Ea and highest prevalence of LVDD. In addition, both baPWV and ECG-determined LVH were independently associated with Ea and LVDD. Hence, assessment of arterial stiffness by baPWV and LVH by ECG may be useful in identifying the high risk group of LVDD.

  12. Effect of continuous positive airway pressure on arterial stiffness in patients with obstructive sleep apnea and hypertension: a meta-analysis.

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    Lin, Xin; Chen, Gongping; Qi, Jiachao; Chen, Xiaofang; Zhao, Jiangming; Lin, Qichang

    2016-12-01

    Arterial stiffness has been recognized as a predictor of cardiovascular and all-cause mortality in hypertensive patients. However, the impact of continuous positive airway pressure (CPAP) on arterial stiffness in patients with OSA and hypertension remains inconclusive. We performed a meta-analysis to determine whether effective CPAP therapy could decrease arterial stiffness. Two reviewers independently searched PubMed, Embase, Web of Science and Cochrane Library prior to March 5, 2015. Information on characteristics of subjects, study design and pre- and post-CPAP treatment of arterial stiffness was extracted for analysis. Standardized mean difference (SMD) was used to analyze the summary estimates for CPAP therapy. Three articles with 186 patients were included in this meta-analysis, including two observational studies and one randomized controlled study. The meta-analysis showed that CPAP was associated with a statistically significant decrease in arterial stiffness in patients with OSA and hypertension (SMD = -0.65, 95 % confidence interval (CI) = -1.14 to -0.16, z = 2.60, p = 0.009). Our meta-analysis suggested that CPAP among OSA and hypertensive patients was significantly associated with a decrease in arterial stiffness. Further prospective large-scale multicenter RCTs are needed to explore the precise impact of CPAP therapy on arterial stiffness in patients with OSA and hypertension.

  13. Arterial stiffness in periodontitis patients and controls. A case–control and pilot intervention study.

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    Houcken, W; Teeuw, W J; Bizzarro, S; Alvarez Rodriguez, E; Mulders, T A; van den Born, B-Jh; Loos, B G

    2016-01-01

    Increased arterial stiffness (AS) is an important indicator for atherosclerotic cardiovascular disease (ACVD). Epidemiologically, periodontitis and ACVD are associated. Therefore, we aimed to investigate AS in periodontitis patients and controls. In addition, we explored the effect of periodontal therapy on AS in a sub-group of cases. Pulse-wave velocity (PWV), a non-invasive chair-side function test for AS, was measured in periodontitis patients (n=57; mean age 46.6 years) and compared with a reference group (n=48; mean age 45.5 years). In addition, 45 cases (mean age 46.9 years) were 6 months followed after periodontal treatment, to explore a possible effect on arterial function. Periodontitis patients showed a significantly increased PWV compared with the reference group (8.01±0.20 vs. 7.36±0.22 m s(-1) respectively; P=0.029) and this remained significant after adjustments for ACVD risk factors (P=0.019). After periodontal therapy, no significant reduction in PWV was seen (8.00±1.8 to 7.82±1.6 m s(-1); P=0.13), but systolic blood pressure (SBP) was significantly reduced (119.8±14.6 to 116.9±15.1 mm Hg; P=0.040). It can be concluded that periodontitis is associated with increased AS. This confirms with a new parameter the association of periodontitis with ACVD. Although periodontal treatment did not lower AS significantly, a modest reduction of SBP after 6 months was observed.

  14. Long-term use of first-line highly active antiretroviral therapy is not associated with carotid artery stiffness in human immunodeficiency virus-positive patients

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    Haohui Zhu

    2014-09-01

    Full Text Available Objective: To evaluate whether or not highly active antiretroviral therapy is associated with carotid artery stiffness in human immunodeficiency virus-positive patients in Henan Province, China. Method: Fifty human immunodeficiency virus-positive patients with at least a 5-year history of highly active antiretroviral therapy use and 50 human immunodeficiency virus-positive patients without a history of highly active antiretroviral therapy use were enrolled in this study. Carotid artery intima-media thickness and stiffness were determined by quantitative inter-media thickness and quantitative artery stiffness, respectively. Results: No statistically significant difference in carotid artery intima-media thickness and stiffness was observed between groups. A significant association between human immunodeficiency virus infection time and carotid artery stiffness was observed, but no significant association between human immunodeficiency virus infection time and intima-media thickness was found. No significant association between intima-media thickness, stiffness, and CD4+ and CD8+ T-cell counts were observed. Conclusion: The first-line highly active antiretroviral therapy currently used in China is not associated with carotid artery stiffness in human immunodeficiency virus-positive patients with good highly active antiretroviral therapy compliance. Human immunodeficiency virus may play a role in the development of atherosclerosis.

  15. Comparison of the effects of antihypertensive agents on central blood pressure and arterial stiffness in isolated systolic hypertension.

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    Mackenzie, Isla S; McEniery, Carmel M; Dhakam, Zahid; Brown, Morris J; Cockcroft, John R; Wilkinson, Ian B

    2009-08-01

    Isolated systolic hypertension is an important risk factor for cardiovascular disease and results primarily from elastic artery stiffening. Although various drug therapies are used to lower peripheral blood pressure (BP) in patients with isolated systolic hypertension, the effects of the 4 major classes of antihypertensive agents on central BP, pulse pressure (PP) amplification, and arterial stiffness in this condition are not clear. Fifty-nine patients over the age of 60 years with untreated isolated systolic hypertension (systolic BP > or =140 mm Hg and diastolic BP hypertension, the choice of therapy may be influenced by these findings in the future.

  16. Carotid Arterial Stiffness and Its Relationship to Exercise Intolerance in Older Patients with Heart Failure and Preserved Ejection Fraction

    OpenAIRE

    Kitzman, Dalane W.; Herrington, David M.; Brubaker, Peter H.; Moore, J. Brian; Eggebeen, Joel; Haykowsky, Mark J

    2012-01-01

    Heart failure with a preserved ejection fraction (HFpEF) is the dominant form of heart failure in the older population. The primary chronic symptom in HFpEF is severe exercise intolerance, however, its pathophysiology and therapy are not well understood. We tested the hypothesis that older patients with HFpEF have increased arterial stiffness beyond that which occurs with normal aging and that this contributes to their severe exercise intolerance.

  17. To compare the effect of Telmisartan with Metoprolol on arterial stiffness in hypertension: Prospective randomized parallel group trial

    Science.gov (United States)

    Sumbria, Minakshi; Negi, Prakash C.; Sahai, Ashok K.; Kaundal, Purshotam K.

    2014-01-01

    Background Hypertension is often complicated by increased arterial stiffness and is an independent predictor of adverse cardiovascular (CV) outcome. Beta blockers and angiotensin receptor blockers (ARBs) are commonly used antihypertensive agents. The effect of beta blockers and ARBs on arterial stiffness has not been compared adequately. The aim of the present study is to compare the effect of telmisartan with metoprolol on arterial stiffness in hypertensive patients in prospective open label randomized parallel group intervention study. Methods 100 patients of hypertension, not on any antihypertensive agents, were enrolled after obtaining informed consent. Baseline recording of data related to demographics, CV risk factors, anthropometry and BP were made. Arterial stiffness was measured noninvasively by recording pulse wave velocity (PWV) using periscope (Genesis medical system). Left ventricular (LV) mass was measured using 2D guided M-mode echocardiography. Blood sugar, renal function, lipids and uric acid estimations were done in fasting state. Patients were randomized to receive metoprolol and telmisartan using stratified randomization technique. Dose of the study drugs were titrated to achieve target BP of <140/90 mmHg. Data related to PWV, BP, anthropometry and blood biochemistry was repeated after 6 months of treatment with study drugs. Results Telmisartan resulted in significantly greater reduction in arterial stiffness index (ASI) in left and right lower limb arterial bed (39.9 ± 11.7 vs. 46.8 ± 17.0 m/s, p < 0.02) and (36.4 ± 9.6 vs. 44.86 ± 15.1 m/s, p < 0.002) respectively and systolic blood pressure (SBP) (−4.9 mmHg with 95% C.I. of −8.0–1.7 mmHg, p < 0.003) compared to metoprolol. Reduction in diastolic blood pressure (DBP) in telmisartan and metoprolol groups was not different statistically (−1.0 mmHg with 95% C.I. of −3.3–1.2 mmHg, p < 0.3). The change in LV mass was not significantly different between the

  18. Astaxanthin vs placebo on arterial stiffness, oxidative stress and inflammation in renal transplant patients (Xanthin: a randomised controlled trial

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    Robertson Iain K

    2008-12-01

    Full Text Available Abstract Background There is evidence that renal transplant recipients have accelerated atherosclerosis manifest by increased cardiovascular morbidity and mortality. The high incidence of atherosclerosis is, in part, related to increased arterial stiffness, vascular dysfunction, elevated oxidative stress and inflammation associated with immunosuppressive therapy. The dietary supplement astaxanthin has shown promise as an antioxidant and anti-inflammatory therapeutic agent in cardiovascular disease. The aim of this trial is to investigate the effects of astaxanthin supplementation on arterial stiffness, oxidative stress and inflammation in renal transplant patients. Method and Design This is a randomised, placebo controlled clinical trial. A total of 66 renal transplant recipients will be enrolled and allocated to receive either 12 mg/day of astaxanthin or an identical placebo for one-year. Patients will be stratified into four groups according to the type of immunosuppressant therapy they receive: 1 cyclosporine, 2 sirolimus, 3 tacrolimus or 4 prednisolone+/-azathioprine, mycophenolate mofetil or mycophenolate sodium. Primary outcome measures will be changes in 1 arterial stiffness measured by aortic pulse wave velocity (PWV, 2 oxidative stress assessed by plasma isoprostanes and 3 inflammation by plasma pentraxin 3. Secondary outcomes will include changes in vascular function assessed using the brachial artery reactivity (BAR technique, carotid artery intimal medial thickness (CIMT, augmentation index (AIx, left ventricular afterload and additional measures of oxidative stress and inflammation. Patients will undergo these measures at baseline, six and 12 months. Discussion The results of this study will help determine the efficacy of astaxanthin on vascular structure, oxidative stress and inflammation in renal transplant patients. This may lead to a larger intervention trial assessing cardiovascular morbidity and mortality. Trial Registration

  19. Association between serum 25-hydroxyvitamin D3 concentration,parathyroid hormone,and arterial stiffness in patients with type 2 diabetes

    Institute of Scientific and Technical Information of China (English)

    马笑堃

    2013-01-01

    Objective To evaluate the association between serum 25-hydroxyvitamin D3[25 (OH) D3],parathyroid hormone,and arterial stiffness in patients with type 2 diabetes.Methods Serum 25 (OH) D3and parathyroid hormone (PTH) were determined in a cross-sectional sample of 258 patients aged 30 years or over.Arterial stiffness was assessed by pulse wave velocity (PWV) obtained with a VP-1000 pulse wave unit.Fasting plasma HbA1C,

  20. A cohort evaluation on arterial stiffness and hypertensive disorders in pregnancy

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    Lim Wai Yee

    2012-12-01

    Full Text Available Abstract Background Hypertensive disorders in pregnancy are associated with systemic endothelial dysfunction leading to impaired physiological vasodilation. Recent evidence has shown central aortic pressures obtained through pulse wave analysis, at less than 14 weeks of gestation, to be predictive of pre-eclampsia. In light of this, we aimed to evaluate the role of central aortic stiffness in the prediction and discrimination of hypertensive disorders in pregnancy. Methods A cohort study of women with viable, singleton pregnancies at less than 14 weeks of amenorrhoea, and without multiple pregnancies, autoimmune or renal disease, diagnosed with aneuploidy or fetal anomaly will be recruited from a single maternity hospital and followed up till delivery and puerperium. A targeted sample size of 1000 eligible pregnant women will be enrolled into the study from antenatal clinics. Main exposure under study is central aortic pulse pressure using radial pulse wave recording, and the outcomes under follow-up are gestational hypertension and pre-eclampsia. Other measures include lifestyle factors such as smoking, physical exercise, psychometric evaluations, vasoactive factors, uterine artery pulsatility index, height and weight measurements. These measures will be repeated over 4 antenatal visits at 11-14, 18-22, 28-32 and above 34 weeks of gestation. Double data entry will be performed on Microsoft Access, and analysis of data will include the use of random effect models and receiver operating characteristic curves on Stata 11.2. Discussion The proposed study design will enable a longitudinal evaluation of the central aortic pressure changes as a marker for vascular compliance during pregnancy. As measures are repeated over time, the timing and severity of changes are detectable, and findings may yield important information on how aberrant vascular responses occur and its role in the early detection and prediction of hypertensive disorders.

  1. Association of circulating omentin-1 level with arterial stiffness and carotid plaque in type 2 diabetes

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    Yoo Hye

    2011-11-01

    Full Text Available Abstract Background Adipokines contribute directly to the atherosclerotic process, connecting metabolic disorders such as obesity and diabetes to cardiovascular disease. Omentin-1 is a recently discovered novel adipokine, so data about the relationship of this adipokine to vascular health in type 2 diabetes is limited. Methods We enrolled 60 people with type 2 diabetes, with or without carotid plaque, and 30 participants with normal glucose tolerance. We measured serum omentin-1, high-sensitivity C-reactive protein (hsCRP levels, and the homeostasis model assessment of insulin resistance (HOMA-IR, as well as other cardiovascular risk factors. Vascular health was assessed by brachial ankle pulse wave velocity (baPWV and carotid intima-media thickness (IMT. Results Serum omentin-1 levels were significantly decreased in type 2 diabetes patients compared to normal glucose controls and was further reduced in type 2 diabetes patients with carotid plaque compared to those without carotid plaque. Multiple stepwise regression analysis showed that age, systolic blood pressure, history of use of statins, angiotensin receptor blockers or angiotensin-converting enzyme inhibitors, and serum omentin-1 level were independent factors determining baPWV in people with type 2 diabetes (r2 = 0.637. Furthermore, in multivariate logistic regression analysis, circulating omentin-1 level was an independent decisive factor for the presence of carotid plaque in type 2 diabetes patients, even after adjusting for age, gender, body mass index, systolic blood pressure, fasting blood glucose, low density lipoprotein cholesterol, and history of smoking and medication (odds ratio, 0.621; 95% confidence interval, 0.420-0.919; P = 0.017. Conclusions Circulating omentin-1 level was independently correlated with arterial stiffness and carotid plaque in type 2 diabetes, even after adjusting for other cardiovascular risk factors and detailed medication history.

  2. No association of dietary fiber intake with inflammation or arterial stiffness in youth with type 1 diabetes

    Science.gov (United States)

    Jaacks, Lindsay M.; Crandell, Jamie; Liese, Angela D.; Lamichhane, Archana P.; Bell, Ronny A.; Dabelea, Dana; D'Agostino, Ralph B.; Dolan, Lawrence M.; Marcovina, Santica; Reynolds, Kristi; Shah, Amy S.; Urbina, Elaine M.; Wadwa, R. Paul; Mayer-Davis, Elizabeth J.

    2014-01-01

    Aim To examine the association of dietary fiber intake with inflammation and arterial stiffness among youth with type 1 diabetes (T1D) in the US. Methods Data are from youth ≥ 10 years old with clinically diagnosed T1D for ≥ 3 months and ≥ 1 positive diabetes autoantibody in the SEARCH for Diabetes in Youth Study. Fiber intake was assessed by food frequency questionnaire with measurement error (ME) accounted for by structural sub-models derived using additional 24-hour dietary recall data in a calibration sample and the respective exposure-disease model covariates. Markers of inflammation, measured at baseline, included IL-6 (n=1405), CRP (n=1387), and fibrinogen (n=1340); markers of arterial stiffness, measured approximately 19 months post-baseline, were available in a subset of participants and included augmentation index (n=180), pulse wave velocity (n=184), and brachial distensibility (n=177). Results Mean (SD) T1D duration was 47.9 (43.2) months; 12.5% of participants were obese. Mean (SD) ME-adjusted fiber intake was 15 (2.8) g/day. In multivariable analyses, fiber intake was not associated with inflammation or arterial stiffness. Conclusion Among youth with T1D, fiber intake does not meet recommendations and is not associated with measures of systemic inflammation or vascular stiffness. Further research is needed to evaluate whether fiber is associated with these outcomes in older individuals with T1D or among individuals with higher intakes than those observed in the present study. PMID:24613131

  3. Activation of SIRT1 Attenuates Klotho Deficiency-Induced Arterial Stiffness and Hypertension by Enhancing AMP-Activated Protein Kinase Activity.

    Science.gov (United States)

    Gao, Diansa; Zuo, Zhong; Tian, Jing; Ali, Quaisar; Lin, Yi; Lei, Han; Sun, Zhongjie

    2016-11-01

    Arterial stiffness is an independent risk factor for stroke and myocardial infarction. This study was designed to investigate the role of SIRT1, an important deacetylase, and its relationship with Klotho, a kidney-derived aging-suppressor protein, in the pathogenesis of arterial stiffness and hypertension. We found that the serum level of Klotho was decreased by ≈45% in patients with arterial stiffness and hypertension. Interestingly, Klotho haplodeficiency caused arterial stiffening and hypertension, as evidenced by significant increases in pulse wave velocity and blood pressure in Klotho-haplodeficient (KL(+/-)) mice. Notably, the expression and activity of SIRT1 were decreased significantly in aortic endothelial and smooth muscle cells in KL(+/-) mice, suggesting that Klotho deficiency downregulates SIRT1. Treatment with SRT1720 (15 mg/kg/d, IP), a specific SIRT1 activator, abolished Klotho deficiency-induced arterial stiffness and hypertension in KL(+/-) mice. Klotho deficiency was associated with significant decreases in activities of AMP-activated protein kinase α (AMPKα) and endothelial NO synthase (eNOS) in aortas, which were abolished by SRT1720. Furthermore, Klotho deficiency upregulated NADPH oxidase activity and superoxide production, increased collagen expression, and enhanced elastin fragmentation in the media of aortas. These Klotho deficiency-associated changes were blocked by SRT1720. In conclusion, this study provides the first evidence that Klotho deficiency downregulates SIRT1 activity in arterial endothelial and smooth muscle cells. Pharmacological activation of SIRT1 may be an effective therapeutic strategy for arterial stiffness and hypertension.

  4. Benidipine has effects similar to losartan on the central blood pressure and arterial stiffness in mild to moderate essential hypertension

    Institute of Scientific and Technical Information of China (English)

    Sang-Hyun Ihm; Hui-Kyung Jeon; Shung Chull Chae; Do-Sun Lim; Kee-Sik Kim; Dong-Ju Choi; Jong-Won Ha

    2013-01-01

    Background Central blood pressure (BP) is pathophysiologically more important than peripheral BP for the pathogenesis of cardiovascular disease.Arterial stiffness is also a good predictor of cardiovascular morbidity and mortality.The effects of benidipine,a unique dual L-/T-type calcium channel blocker,on central BP have not been reported.This study aimed to compare the effect of benidipine and losartan on the central BP and arterial stiffness in mild to moderate essential hypertensives.Methods This 24 weeks,multi-center,open label,randomized,active drug comparative,parallel group study was designed as a non-inferiority study.The eligible patients (n=200) were randomly assigned to receive benidipine (n=101)or losartan (n=99).Radial artery applanation tonometry and pulse wave analysis were used to measure the central BP,pulse wave velocity (PWV) and augmentation index (Alx).We also measured the metabolic and inflammatory markers.Results After 24 weeks,the central BP decreased significantly from baseline by (16.8+14.0/10.5+9.2) mmHg (1mmHg =0.133 kPa) (systolic/diastolic BP; P <0.001) in benidipine group and (18.9+14.7/12.1+10.2) mmHg (P <0.001)in losartan group respectively.Both benidipine and losartan groups significantly lowered peripheral BP (P <0.001) and Alx (P <0.05),but there were no significant differences between the two groups.The mean aortic,brachial and femoral PWV did not change in both groups after 24-week treatment.There were no significant changes of the blood metabolic and inflammatory biomarkers in each group.Conclusion Benidipine is as effective as losartan in lowering the central and peripheral BP,and improving arterial stiffness.

  5. Low-sodium dietary approaches to stop hypertension diet reduces blood pressure, arterial stiffness, and oxidative stress in hypertensive heart failure with preserved ejection fraction.

    Science.gov (United States)

    Hummel, Scott L; Seymour, E Mitchell; Brook, Robert D; Kolias, Theodore J; Sheth, Samar S; Rosenblum, Hannah R; Wells, Joanna M; Weder, Alan B

    2012-11-01

    Recent studies suggest that oxidative stress and vascular dysfunction contribute to heart failure with preserved ejection fraction (HFPEF). In salt-sensitive HFPEF animal models, diets low in sodium and high in potassium, calcium, magnesium, and antioxidants attenuate oxidative stress and cardiovascular damage. We hypothesized that the sodium-restricted Dietary Approaches to Stop Hypertension diet (DASH/SRD) would have similar effects in human hypertensive HFPEF. Thirteen patients with treated hypertension and compensated HFPEF consumed the DASH/SRD for 21 days (all food/most beverages provided). The DASH/SRD reduced clinic systolic (155-138 mm Hg; P=0.02) and diastolic blood pressure (79-72 mm Hg; P=0.04), 24-hour ambulatory systolic (130-123 mm Hg; P=0.02) and diastolic blood pressure (67-62 mm Hg; P=0.02), and carotid-femoral pulse wave velocity (12.4-11.0 m/s; P=0.03). Urinary F2-isoprostanes decreased by 31% (209-144 pmol/mmol Cr; P=0.02) despite increased urinary aldosterone excretion. The reduction in urinary F2-isoprostanes closely correlated with the reduction in urinary sodium excretion on the DASH/SRD. In this cohort of HFPEF patients with treated hypertension, the DASH/SRD reduced systemic blood pressure, arterial stiffness, and oxidative stress. These findings are characteristic of salt-sensitive hypertension, a phenotype present in many HFPEF animal models and suggest shared pathophysiological mechanisms linking these 2 conditions. Further dietary modification studies could provide insights into the development and progression of hypertensive HFPEF.

  6. Aerobic exercise training-induced changes in serum adropin level are associated with reduced arterial stiffness in middle-aged and older adults.

    Science.gov (United States)

    Fujie, Shumpei; Hasegawa, Natsuki; Sato, Koji; Fujita, Satoshi; Sanada, Kiyoshi; Hamaoka, Takafumi; Iemitsu, Motoyuki

    2015-11-15

    Aging-induced arterial stiffening is reduced by aerobic exercise training, and elevated production of nitric oxide (NO) participates in this effect. Adropin is a regulator of endothelial NO synthase and NO release, and circulating adropin level decreases with age. However, the effect of habitual aerobic exercise on circulating adropin levels in healthy middle-aged and older adults remains unclear. We sought to determine whether serum adropin level is associated with exercise training-induced changes in arterial stiffness. First, in a cross-sectional study, we investigated the association between serum adropin level and both arterial stiffness and cardiorespiratory fitness in 80 healthy middle-aged and older subjects (65.6 ± 0.9 yr). Second, in an intervention study, we examined the effects of 8-wk aerobic exercise training on serum adropin level and arterial stiffness in 40 healthy middle-aged and older subjects (67.3 ± 1.0 yr) divided into two groups: aerobic exercise training and sedentary controls. In the cross-sectional study, serum adropin level was negatively correlated with carotid β-stiffness (r = -0.437, P aerobic exercise training intervention, and training-induced changes in serum adropin level were correlated with training-induced changes in carotid β-stiffness (r = -0.399, P exercise-induced reduction of arterial stiffness.

  7. Evaluation of cardiac autonomic nerves by iodine-123 metaiodobenzylguanidine scintigraphy and ambulatory electrocardiography in patients after arterial switch operations

    Energy Technology Data Exchange (ETDEWEB)

    Sakurai, Hajime; Maeda, Masanobu; Miyahara, Ken [Shakaihoken Chukyo Hospital, Nagoya (Japan)] [and others

    2000-05-01

    The autonomic cardiac nerves reach the heart after passing through the vicinity of the aortic root and the pulmonary trunk. The arterial switch operation (ASO) completely transects the ascending aorta and the pulmonary trunk. Therefore, this surgical procedure virtually denerves the heart. Cardiac sympathetic denervation and reinnervation were evaluated in patients after ASO using iodine-123 metaiodobenzylguanidine (MIBG) myocardial scintigraphy and parasympathetic denervation and reinnervation using ambulatory electrocardiography [Holter electrocardiogram (ECG)]. MIBG scintigraphy was performed in 14 patients who underwent ASO (ASO group) and 3 patients who underwent other open heart surgery (control group). All patients in the ASO group underwent the operation in the neonatal or infantile period. Planar and single photon emission computed tomography (SPECT) images of the myocardium were obtained. Defect score was determined by the SPECT images as a semi-quantitative index. The mean interval between ASO and MIBG scintigraphy was 25.6{+-}14.6 months. Holter ECG was also performed in 14 patients in the ASO group and 19 age-matched normal children. The Holter ECGs were plotted on a Lorenz plot. The H index, which is related to vagal tone for the cardiovascular system, was calculated from the R-R intervals. The mean interval between the ASO and Holter ECG was 8.3{+-}9.7 months. MIBG scintigraphy in the control group demonstrated an almost normal homogeneous tracer uptake, but showed extremely reduced tracer uptake and significantly higher defect score in the ASO group. The extent and degree of the reduction of MIBG uptake improved with time after the ASO. The heart-to-mediastinum MIBG count ratio tended to increase with time. The H index of the ASO group was lower than that of normal children (<12 months: Control group 0.0280{+-}0.0068 vs ASO group 0.0219{+-}0.0083), and gradually increased with time (1-3 years: 0.0470{+-}0.0157 vs 0.0314{+-}0.0124). (author)

  8. The Association of Endothelin-1 with Markers of Arterial Stiffness in Black South African Women: The SABPA Study

    Directory of Open Access Journals (Sweden)

    Christine Susara du Plooy

    2015-01-01

    Full Text Available Background. Limited data exist regarding endothelin-1 (ET-1, a vasoactive contributor in vascular tone, in a population subjected to early vascular deterioration. We compared ET-1 levels and explored its association with markers of arterial stiffness in black and white South Africans. Methodology. This cross-sectional substudy included 195 black (men: n=99; women: n=95 and 197 white (men: n=99; women: n=98 South Africans. Serum ET-1 levels were measured as well as markers of arterial stiffness (blood pressure, pulse wave velocity, and arterial compliance. ET-1 levels were higher in black men and white women compared to their counterparts after adjusting for C-reactive protein. In both single and partial (adjusting for body mass index and gamma glutamyl transferase regression analyses ET-1 correlated with age, interleukin-6, high density lipoprotein cholesterol, systolic blood pressure, pulse pressure, and pulse wave velocity in black women. In multivariate regression analyses the independent association of ET-1 with systolic blood pressure (Adj. R2=0.13; β=0.28, p<0.01 and pulse pressure (Adj. R2=0.11; β=0.27, p<0.01 was confirmed in black women only. ET-1 additionally associated with interleukin-6 in black women (p<0.01. Conclusion. Our result suggests that ET-1 and its link with subclinical arteriosclerosis are potentially driven by low-grade inflammation as depicted by the association with interleukin-6 in the black female cohort.

  9. Relationship between uric acid and arterial stiffness in the elderly with metabolic syndrome components

    Institute of Scientific and Technical Information of China (English)

    SUN Ning; ZHANG Yun; TIAN Jian-li; WANG Hui

    2013-01-01

    Background High uric acid (UA) levels and metabolic syndrome (MS) are risk factors for atherosclerotic diseases.Brachial-ankle pulse wave velocity (baPWV) is a valid and reproducible measurement by which to assess arterial stiffness and a surrogate marker of atherosclerosis.However,little is known about the relationship between them,especially in elderly Chinese with MS components who are at high risk for atherosclerotic diseases.Methods One thousand and twenty Chinese subjects (159 women) older than 60 years of age (mean age (70.6±5.7)years) with at least one MS component underwent routine laboratory tests,and baPWV measurements were analyzed.Results Participants were divided into four groups by MS components.The mean age did not significantly differ among the MS component groups.We found that not only the diagnostic factors (blood pressure,body mass index (BMI),lipids,glucose) of MS but also baPWV,UA,insulin,homeostasis model of assessment for insulin resistence index (HOMAIR) levels increased,and high density lipoprotein (HDL)-C decreased with an increased number of MS components (test for trend P<0.05).The association between UA and baPWV was observed after adjustment for gender,age,blood pressure,BMI,serum creatinine and high density lipoprotein,and insulin resistance (r=0.186,P<0.0001).There were increases in the odds ratios for the association between the number of components of MS,UA and baPWV,even after adjustment for traditional risk factors.However,after adjustment for insulin or HOMA-IR,there were no significant differences in the multivariate odds ratios among the number of MS components for UA.Conclusions The UA level is positively associated with baPWV and MS,but the association between UA and MS is dependent on insulin resistance.Furthermore,baPWV is independently associated with MS in our study population.

  10. Estimated aortic blood pressure based on radial artery tonometry underestimates directly measured aortic blood pressure in patients with advancing chronic kidney disease staging and increasing arterial stiffness

    DEFF Research Database (Denmark)

    Carlsen, Rasmus K; Peters, Christian D; Khatir, Dinah S;

    2016-01-01

    we compared invasive aortic systolic BP (SBP) with estimated central SBP obtained by radial artery tonometry and examined the influence of renal function and arterial stiffness on this relationship. We evaluated 83 patients with stage 3 to 5 CKD (mean estimated glomerular filtration rate [eGFR] 30 ml......% confidence interval -14.9 to -11.4) mm Hg. Arterial stiffness was evaluated by carotid-femoral pulse wave velocity (cf-PWV) and was significantly increased in CKD patients compared with (versus) control patients (mean 10.7 vs. 9.3 m/s). The difference in BP significantly increased 1.0 mm Hg for every 10 ml....../min decrease in eGFR and by 1.6 mm Hg per 1 m/s increase in cfPWV. Using multivariate regression analysis including both eGFR and cfPWV, the difference between estimated central and invasive aortic SBP was significantly increased by 0.7 mm Hg. For the entire cohort brachial SBP significantly better reflected...

  11. Low Physical Activity Is Associated With Increased Arterial Stiffness in Patients Recently Diagnosed With Type 2 Diabetes

    DEFF Research Database (Denmark)

    Funck, Kristian L; Laugesen, Esben; Høyem, Pernille;

    2015-01-01

    AIMS: Several studies have indicated that low physical activity is associated with increased risk of cardiovascular disease (CVD) and all-cause mortality among patients with diabetes. The association between physical activity and subclinical cardiovascular changes preceding clinical events remains...... to be elucidated. We investigated the relationship between physical activity and arterial stiffness, an independent predictor of CVD, in patients with type 2 diabetes and controls. METHODS: We included 100 patients with type 2 diabetes and 100 sex- and age-matched controls in a cross-sectional study. Arterial...... of physical activity was defined according to the median level of activity (cpm = 31). RESULTS: Sixty-five patients and 65 controls were included in the final analysis (median age 59 years, 55% men, median diabetes duration 1.9 years). Participants with low physical activity had higher cfPWV compared...

  12. Association of Serum 25-hydroxy-vitamin D Concentration and Arterial Stiffness among Korean Adults in Single Center

    Science.gov (United States)

    Lee, Jung Hae

    2017-01-01

    Background There are growing concerns about the role of vitamin D deficiency in cardiovascular diseases. Therefore, we investigated the correlation between serum 25-hydroxy-vitamin D (25[OH]D) and arterial stiffness among Korean adults. Methods We retrospectively reviewed the medical charts of 302 people (115 women and 187 men) who visited a tertiary hospital from January 2015 to December 2016. Serum 25(OH)D was measured using the radioimmunoassay technique, and brachial-ankle pulse wave velocity (baPWV) was measured using an automatic wave analyzer. We obtained the doctor's report on the medical history of the participants, their alcohol consumption and smoking habits, and their exercise status. Metabolic syndrome was diagnosed based on guidelines from the National Cholesterol Education Program (NCEP)-Adult Treatment Panel (ATP III) and the International Diabetes Federation (IDF). Results of basic blood tests and physical assessment were also collected. Results In the Pearson correlation analysis, serum 25(OH)D and baPWV showed a statistically significant inverse relationship (r=-0.279, P<0.001). Using multiple regression analysis, and after adjusting for possible confounders, serum 25(OH)D concentration was found to be significantly associated with baPWV (β=-0.121, P=0.011). Conclusions We observed an association between serum 25(OH)D concentration and arterial stiffness. Further studies involving larger sample sizes will be needed to confirm this associations.

  13. The Relationship Between Osteoprotegerin/RANKL Axis and Arterial Stiffness in Osteopenic/Osteoporotic Renal Transplantation Recipients

    Directory of Open Access Journals (Sweden)

    İsmail KOÇYIĞI

    2015-09-01

    Full Text Available OBJECTIVE: Cardiovascular diseases are the main reason of death in patients with renal transplantation (Rtx. Osteoprotegerin (OPG is produced by osteoblasts and is linked to increased cardiovascular risk in Rtx. OPG acts as a decoy receptor binding receptor activator of nuclear factor kappa-B ligand (RANKL and this interaction plays a role in bone resorption and vascular function. This study aimed to investigate the relation between OPG, RANKL, osteoporosis and arterial stiffness in Rtx patients. MATERIAL and METHODS: This cross-sectional study included 80 adult Rtx recipients. Femoral neck mineral density was obtained by dual-energy X-ray absorptiometry. Serum OPG and RANKL were measured by the ELISA method. Pulse-wave analysis was measured in the carotid and femoral arteries using a pulse wave velocity (PWV machine. RESULTS: Patients were divided into two groups as normal (n:24 and osteopenia/osteoporosis group (n:56. Body mass index was significantly lower in the osteopenic/osteoporotic group compared to the normal group. Pulse wave velocity was positively correlated with age (r:0.204,p:0.072, osteoprotegerin (r:0.219,p:0.052, calcium x phosphate product (r:0.605,p:<0.001, and systolic blood pressure (r:0.198,p:0.058 and negatively correlated with RANKL (r:-0.261,p:0.020 and creatinine clearance (r:-0.220,p:0.051. PWV was independently predicted by calcium x phosphate product but not creatinine clearance, RANKL, osteoprotegerin and systolic blood pressure. CONCLUSION: In our study, serum calcium x phosphate product but not OPG and RANKL levels were found to be the main predictor of arterial stiffness in Rtx patients.

  14. Effect of cinnamon on gastric emptying, arterial stiffness, postprandial lipemia, glycemia, and appetite responses to high-fat breakfast

    Directory of Open Access Journals (Sweden)

    Trinick Tom R

    2011-09-01

    Full Text Available Abstract Background Cinnamon has been shown to delay gastric emptying of a high-carbohydrate meal and reduce postprandial glycemia in healthy adults. However, it is dietary fat which is implicated in the etiology and is associated with obesity, type 2 diabetes and cardiovascular disease. We aimed to determine the effect of 3 g cinnamon (Cinnamomum zeylanicum on GE, postprandial lipemic and glycemic responses, oxidative stress, arterial stiffness, as well as appetite sensations and subsequent food intake following a high-fat meal. Methods A single-blind randomized crossover study assessed nine healthy, young subjects. GE rate of a high-fat meal supplemented with 3 g cinnamon or placebo was determined using the 13C octanoic acid breath test. Breath, blood samples and subjective appetite ratings were collected in the fasted and during the 360 min postprandial period, followed by an ad libitum buffet meal. Gastric emptying and 1-day fatty acid intake relationships were also examined. Results Cinnamon did not change gastric emptying parameters, postprandial triacylglycerol or glucose concentrations, oxidative stress, arterial function or appetite (p half and 1-day palmitoleic acid (r = -0.78, eiconsenoic acid (r = -0.84 and total omega-3 intake (r = -0.72. The ingestion of 3 g cinnamon had no effect on GE, arterial stiffness and oxidative stress following a HF meal. Conclusions 3 g cinnamon did not alter the postprandial response to a high-fat test meal. We find no evidence to support the use of 3 g cinnamon supplementation for the prevention or treatment of metabolic disease. Dietary fatty acid intake requires consideration in future gastrointestinal studies. Trial registration Trial registration number: at http://www.clinicaltrial.gov: NCT01350284

  15. Effect of androgen suppression compared with androgen receptor blockade on arterial stiffness in men with prostate cancer.

    Science.gov (United States)

    Dockery, Frances; Bulpitt, Christopher J; Agarwal, Sanjiv; Vernon, Clare; Rajkumar, Chakravarthi

    2009-01-01

    Endogenous testosterone and estradiol are thought to be cardio-protective in men. We wanted to determine the effects of 2 different anti-androgen therapies on arterial stiffness as one suppresses (goserelin--a gonadotrophin-releasing hormone analog) while the other increases (bicalutamide--an androgen receptor blocker) both testosterone and estradiol. We conducted a randomized trial on 43 men (mean age, 71.2 +/- 6.2 years) with localized prostate cancer. They received either goserelin or bicalutamide for 24 weeks. Carotid-femoral (C-F) and carotid-radial (C-R) pulse wave velocities (PWVs) were measured. Twenty age- and disease-matched men with prostate cancer on no active treatment were studied in a similar manner. After 12 weeks of goserelin, radial artery PWV increased significantly from baseline and a nonsignificant increase was observed in femoral PWV (change from baseline radial: +1.4 m/s, P = .002, femoral: +0.9 m/s, P = .127) Both PWV measures increased significantly with bicalutamide (change from baseline radial: +0.8, femoral: +0.9 m/s, P change from baseline radial: +1.7, femoral: +1.3 m/s, P change from baseline radial: +0.4, femoral: +0.4 m/s, P not significant [NS]); however, comparison of changes between the 2 drugs were not significantly different at either 12 or 24 weeks (P >or= .967 at 12 weeks and P >or= .07 at 24 weeks). The untreated men studied in parallel showed no changes at 12 or 24 weeks in either PWV measure. Anti-androgen treatment in men might increase large artery stiffness, an adverse cardiovascular risk factor; however, the effect was not maintained with testosterone receptor blockade, in the longer term, but tended to be sustained with suppression therapy. This could relate to the different sex hormone effects of the 2 therapies.

  16. Effect of cinnamon on gastric emptying, arterial stiffness, postprandial lipemia, glycemia, and appetite responses to high-fat breakfast

    LENUS (Irish Health Repository)

    Markey, Oonagh

    2011-09-07

    Abstract Background Cinnamon has been shown to delay gastric emptying of a high-carbohydrate meal and reduce postprandial glycemia in healthy adults. However, it is dietary fat which is implicated in the etiology and is associated with obesity, type 2 diabetes and cardiovascular disease. We aimed to determine the effect of 3 g cinnamon (Cinnamomum zeylanicum) on GE, postprandial lipemic and glycemic responses, oxidative stress, arterial stiffness, as well as appetite sensations and subsequent food intake following a high-fat meal. Methods A single-blind randomized crossover study assessed nine healthy, young subjects. GE rate of a high-fat meal supplemented with 3 g cinnamon or placebo was determined using the 13C octanoic acid breath test. Breath, blood samples and subjective appetite ratings were collected in the fasted and during the 360 min postprandial period, followed by an ad libitum buffet meal. Gastric emptying and 1-day fatty acid intake relationships were also examined. Results Cinnamon did not change gastric emptying parameters, postprandial triacylglycerol or glucose concentrations, oxidative stress, arterial function or appetite (p < 0.05). Strong relationships were evident (p < 0.05) between GE Thalf and 1-day palmitoleic acid (r = -0.78), eiconsenoic acid (r = -0.84) and total omega-3 intake (r = -0.72). The ingestion of 3 g cinnamon had no effect on GE, arterial stiffness and oxidative stress following a HF meal. Conclusions 3 g cinnamon did not alter the postprandial response to a high-fat test meal. We find no evidence to support the use of 3 g cinnamon supplementation for the prevention or treatment of metabolic disease. Dietary fatty acid intake requires consideration in future gastrointestinal studies. Trial registration Trial registration number: at http:\\/\\/www.clinicaltrial.gov: NCT01350284

  17. A decreased level of serum soluble Klotho is an independent biomarker associated with arterial stiffness in patients with chronic kidney disease.

    Directory of Open Access Journals (Sweden)

    Masashi Kitagawa

    Full Text Available BACKGROUND: Klotho was originally identified in a mutant mouse strain unable to express the gene that consequently showed shortened life spans. In humans, low serum Klotho levels are related to the prevalence of cardiovascular diseases in community-dwelling adults. However, it is unclear whether the serum Klotho levels are associated with signs of vascular dysfunction such as arterial stiffness, a major determinant of prognosis, in human subjects with chronic kidney disease (CKD. METHODS: We determined the levels of serum soluble Klotho in 114 patients with CKD using ELISA and investigated the relationship between the level of Klotho and markers of CKD-mineral and bone disorder (CKD-MBD and various types of vascular dysfunction, including flow-mediated dilatation, a marker of endothelial dysfunction, ankle-brachial pulse wave velocity (baPWV, a marker of arterial stiffness, intima-media thickness (IMT, a marker of atherosclerosis, and the aortic calcification index (ACI, a marker of vascular calcification. RESULTS: The serum Klotho level significantly correlated with the 1,25-dihydroxyvitamin D level and inversely correlated with the parathyroid hormone level and the fractional excretion of phosphate. There were significant decreases in serum Klotho in patients with arterial stiffness defined as baPWV≥1400 cm/sec, atherosclerosis defined as maximum IMT≥1.1 mm and vascular calcification scores of ACI>0%. The serum Klotho level was a significant determinant of arterial stiffness, but not endothelial dysfunction, atherosclerosis or vascular calcification, in the multivariate analysis in either metabolic model, the CKD model or the CKD-MBD model. The adjusted odds ratio of serum Klotho for the baPWV was 0.60 (p = 0.0075. CONCLUSIONS: Decreases in the serum soluble Klotho levels are independently associated with signs of vascular dysfunction such as arterial stiffness in patients with CKD. Further research exploring whether therapeutic approaches

  18. Uncertainty quantification of inflow boundary condition and proximal arterial stiffness coupled effect on pulse wave propagation in a vascular network

    CERN Document Server

    Brault, A; Lucor, D

    2016-01-01

    SUMMARY This work aims at quantifying the effect of inherent uncertainties from cardiac output on the sensitivity of a human compliant arterial network response based on stochastic simulations of a reduced-order pulse wave propagation model. A simple pulsatile output form is utilized to reproduce the most relevant cardiac features with a minimum number of parameters associated with left ventricle dynamics. Another source of critical uncertainty is the spatial heterogeneity of the aortic compliance which plays a key role in the propagation and damping of pulse waves generated at each cardiac cycle. A continuous representation of the aortic stiffness in the form of a generic random field of prescribed spatial correlation is then considered. Resorting to a stochastic sparse pseudospectral method, we investigate the spatial sensitivity of the pulse pressure and waves reflection magnitude with respect to the different model uncertainties. Results indicate that uncertainties related to the shape and magnitude of th...

  19. Azelnidipine plus olmesartan versus amlodipine plus olmesartan on arterial stiffness and cardiac function in hypertensive patients: a randomized trial

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    Takami T

    2013-04-01

    Full Text Available CorrigendumTakami T, Saito Y. Drug Design, Development and Therapy. 2013;7:175–183. On page 177, line 26, heading "Measurement of LVMI and LF diastolic function" should have been "Measurement of LVMI and LV diastolic function". Line 32, "Devereux et al18" should read "Devereux et al19". Line 40, "(E/e’ ratio were measured as previously described.19" should read "(E/e’ ratio were measured as previously described.20". On page 181, line 15, "baPWV with LVMI.20" should read "baPWV with LVMI.21". Line 23, "baPWV and LVMI, E/A ratio.20" should read "baPWV and LVMI, E/A ratio.21,22". Line 28 "diastolic dysfunction.21" should read "diastolic dysfunction.23". Line 38 "is high.22" should read "is high.24". Line 39, "in clinical treatment.23" should read "in clinical treatment.25". Line 57, "A recent cohort study24" should read "A recent cohort study21".On page 182, line 1, "diastolic heart failure.25" should read "diastolic heart failure.26". Line 3, "untreated hypertensive patients.26" should read "untreated hypertensive patients.27". Line 6, "linear regression analysis.27" should read "linear regression analysis.21".On page 183, the references 18 to 27 should be updated as shown below:18. Takami T. Evaluation of arterial stiffness in morning hypertension under high-dose valsartan compared to valsartan plus low-dose diuretic. Hypertens Res. 2009;32:1086–1090.19. Devereux RB, Palmieri V, Sharpe N, et al. Effects of once-daily angiotensin-converting enzyme inhibition and calcium channel blockade-based antihypertensive treatment regimens on left ventricular hypertrophy and diastolic filling in hypertension: the prospective randomized enalapril study evaluating regression of ventricular enlargement (PRESERVE trial. Circulation. 2001;104:1248–1254.20. Ito H, Ishii K, Kihara H, et al. Adding thiazide to a renin-angiotensin blocker improves left ventricular relaxation and improves heart failure in patients with hypertension. Hypertens Res. 2012;35:93

  20. Relationships Among Conventional Cardiovascular Risk Factors and Lifestyle Habits With Arterial Stiffness in Type 2 Diabetic Patients

    Science.gov (United States)

    Hamamura, Misako; Mita, Tomoya; Osonoi, Yusuke; Osonoi, Takeshi; Saito, Miyoko; Tamasawa, Atsuko; Nakayama, Shiho; Someya, Yuki; Ishida, Hidenori; Gosho, Masahiko; Kanazawa, Akio; Watada, Hirotaka

    2017-01-01

    Background While conventional cardiovascular risk factors and certain lifestyle habits are associated with arterial stiffness in patients with type 2 diabetes mellitus (T2DM), it is still unknown whether they are actually associated with arterial stiffness even after adjustment for conventional cardiovascular risk factors and lifestyle habits. The aim of this study was to identify variables that are associated with brachial-ankle pulse wave velocity (baPWV). Methods The study participants comprised 724 Japanese T2DM outpatients free of history of cardiovascular diseases. Lifestyle habits were analyzed using self-reported questionnaires. The associations among conventional cardiovascular risk factors and lifestyle habits with baPWV were investigated by multivariable linear regression analysis. Results The mean age of the study subjects was 57.8 ± 8.6 years, and 62.8% of those were males. The mean HbA1c was 7.0±1.0%, and the estimated duration of T2DM was 9.9 ± 7.2 years. Multiple linear regression analysis that included age and gender demonstrated that age and male sex were positively associated with baPWV. In a model adjusted for numerous conventional cardiovascular risk factors and lifestyle habits, age, duration of T2DM, systolic blood pressure, serum uric acid, urinary albumin excretion and poor sleep quality were positively associated with baPWV, while body mass index was negatively associated with baPWV. Conclusions In Japanese T2DM, in addition to several conventional cardiovascular risk factors, poor sleep quality was associated with baPWV even after adjustment for numerous conventional cardiovascular risk factors and lifestyle habits. PMID:28270889

  1. Relationship of serum osteoprotegerin with arterial stiffness, preclinical atherosclerosis, and disease activity in patients with ankylosing spondylitis.

    Science.gov (United States)

    Serdaroğlu Beyazal, Münevver; Erdoğan, Turan; Türkyılmaz, Aysegül Kücükali; Devrimsel, Gül; Cüre, Medine Cumhur; Beyazal, Mehmet; Sahin, Ismail

    2016-09-01

    Patients with ankylosing spondylitis (AS) reportedly have a higher mortality and morbidity risk. Osteoprotegerin (OPG) was recently defined as an important cardiovascular (CV) marker in the general population. We aimed to assess the relationship of serum OPG levels with arterial stiffness, carotid intima media thickness (CIMT), and clinical and laboratory data in AS patients. We examined 60 AS patients without CV disease or risk factors and 50 healthy controls. Disease activity was evaluated using the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and the Ankylosing Spondylitis Disease Activity Score (ASDAS), whereas functional capacity was evaluated using the Bath Ankylosing Spondylitis Functional Index (BASFI). Serum OPG levels were measured with the enzyme-linked immunosorbent assay. Carotid-femoral pulse wave velocity (PWV) was used as an indicator of arterial stiffness, whereas CIMT (examined via carotid ultrasonography) was used to evaluate preclinical atherosclerosis. The mean serum OPG level, PWV, and CIMT were significantly higher in AS patients than in controls (106.7 ± 50.9 vs. 58.1 ± 12.7 pg/mL; 7.4 ± 1.8 vs. 6.2 ± 1.2 m/s; 0.72 ± 0.13 vs. 0.57 ± 0.07 mm, respectively; P < 0.001 for all). In AS patients, the serum OPG levels were not significantly correlated with PWV and CIMT but were significantly correlated with erthrocyte sedimentation rate, BASFI, and ASDAS. AS patients without CV disease or risk exhibited high OPG levels and increased PWV and CIMT values. Although OPG levels were not significantly correlated with PWV or CIMT, future long-term follow-up studies will help define the predictive value of OPG in these patients.

  2. Cerebral Microbleeds and White Matter Hyperintensities in Cognitively Healthy Elderly: A Cross-Sectional Cohort Study Evaluating the Effect of Arterial Stiffness

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    Anna-Märta Gustavsson

    2015-05-01

    Full Text Available Background: Arterial stiffness reflects the ageing processes in the vascular system, and studies have shown an association between reduced cognitive function and cerebral small vessel disease. Small vessel disease can be visualized as white matter hyperintensities (WMH and lacunar infarcts but also as cerebral microbleeds on brain magnetic resonance imaging (MRI. We aimed to investigate if arterial stiffness influences the presence of microbleeds, WMH and cognitive function in a population of cognitively healthy elderly. Methods: The study population is part of the Swedish BioFinder study and consisted of 208 individuals without any symptoms of cognitive impairment, who scored >27 points on the Mini-Mental State Examination. The participants (mean age, 72 years; 59% women underwent MRI of the brain with visual rating of microbleeds and WMH. Arterial stiffness was measured with carotid-femoral pulse wave velocity (cfPWV. Eight cognitive tests covering different cognitive domains were performed. Results: Microbleeds were detected in 12% and WMH in 31% of the participants. Mean (±standard deviation, SD cfPWV was 10.0 (±2.0 m/s. There was no association between the presence of microbleeds and arterial stiffness. There was a positive association between arterial stiffness and WMH independent of age or sex (odds ratio, 1.58; 95% confidence interval, 1.04-2.40, p 0.05. Cognitive performance was not associated with microbleeds, but individuals with WMH performed slightly worse than those without WMH on the Symbol Digit Modalities Test (mean ± SD, 35 ± 7.8 vs. 39 ± 8.1, p Conclusions: Arterial stiffness was not associated with the presence of cerebral microbleeds or cognitive function in cognitively healthy elderly. However, arterial stiffness was related to the presence of WMH, but the association was attenuated when multiple adjustments were made. There was a weak negative association between WMH and performance in one specific test of attention

  3. [Approaches potentiating cardioprotective effect of ambulatory physical training in patients with ischemic heart disease and multivessel coronary artery involvement after coronary stenting].

    Science.gov (United States)

    Liamina, N P; Kotel'nikova, E V; Biziaeva, E A; Karpova, É S

    2014-01-01

    Cardiorehabilitation of patients with multivessel coronary lesions is an obligatory component of ambulatory stage of care. With the aim of potentiating cardioprotective and antiischemic impact of rehabilitative preventive measures in 36 patients with ischemic heart disease (IHD) and multivessel coronary artery involvement who had undergone percutaneous coronary intervention we studied cardioprotective and antiischemic effect of long-term (24 weeks) administration of 70 mg/day trimetazidine in combination with moderate intensity physical training with the use of distance surveillance by a physician. The chosen therapeutic approach in patients with residual ischemia after incomplete anatomical revascularization provided early persistent formation of cardioprotective and antiischemic effect proven by increase of tolerance to physical exercise, improvement of diastolic function, and positive dynamics of both ECG parameters and biochemical markers of myocardial ischemia.

  4. Phylloquinone (vitamin K₁) intake and pulse pressure as a measure of arterial stiffness in older adults.

    Science.gov (United States)

    Vaccaro, Joan A; Huffman, Fatma G

    2013-01-01

    This study examined the relationships among ethnicity/race, lifestyle factors, phylloquinone (vitamin K₁) intake, and arterial pulse pressure in a nationally representative sample of older adults from four ethnic/racial groups: non-Hispanic Whites, non-Hispanic Blacks, Mexican Americans, and other Hispanics. This was a cross-sectional study of U.S. representative sample with data from the National Health and Nutrition Examination Surveys, 2007-2008 and 2009-2010 of adults aged 50 years and older (N = 5296). Vitamin K intake was determined by 24-hour recall. Pulse pressure was calculated as the difference between the averages of systolic blood pressure and diastolic blood pressure. Compared to White non-Hispanics, the other ethnic/racial groups were more likely to have inadequate vitamin K₁ intake. Inadequate vitamin K₁ intake was an independent predictor of high arterial pulse pressure. This was the first study that compared vitamin K₁ inadequacy with arterial pulse pressure across ethnicities/races in U.S. older adults. These findings suggest that vitamin K screening may be a beneficial marker for the health of older adults.

  5. Estimation of Arterial Stiffness by Time-Frequency Analysis of Pulse Wave

    Science.gov (United States)

    Saito, Masashi; Yamamoto, Yuya; Shibayama, Yuka; Matsukawa, Mami; Watanabe, Yoshiaki; Furuya, Mio; Asada, Takaaki

    2011-07-01

    Evaluation of a pulse wave is effective for the early diagnosis of arteriosclerosis because the pulse wave contains the reflected wave that is the age- and stiffness-dependent component. In this study, we attempted to extract the parameter reflecting the component by pulse wave analysis using continuous wavelet transform. The Morlet wavelet was used as the mother wavelet. We then investigated the relationship between the parameter and the reflected wave that was extracted from the pulse wave by our previously reported separation technique. Consequently, the result of wavelet transform of the differentiated pulse waveform changed markedly owing to age and had medium correlation with the peak of the reflected wave (R=0.68).

  6. Comparison of markers of oxidative stress, inflammation and arterial stiffness between incident hemodialysis and peritoneal dialysis patients – an observational study

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    Ratanjee Sharad

    2009-03-01

    Full Text Available Abstract Background Patients on peritoneal and hemodialysis have accelerated atherosclerosis associated with an increase in cardiovascular morbidity and mortality. The atherosclerosis is associated with increased arterial stiffness, endothelial dysfunction and elevated oxidative stress and inflammation. The aims of this study are to investigate the effects of peritoneal and hemodialysis on arterial stiffness, vascular function, myocardial structure and function, oxidative stress and inflammation in incident patients with end stage kidney disease. Methods This is an observational study. Eighty stage five CKD patients will be enrolled and followed for one-year. Primary outcome measures will be changes in 1 arterial stiffness measured by aortic pulse wave velocity, 2 oxidative stress assessed by plasma F2 isoprostanes and 3 inflammation measured by plasma pentraxin-3. Secondary outcomes will include additional measures of oxidative stress and inflammation, changes in vascular function assessed using the brachial artery reactivity technique, carotid artery intimal medial thickness, augmentation index and trans thoracic echocardiography to assess left ventricular geometry, and systolic and diastolic function. Patients will undergo these measures at baseline (6–8 weeks prior to starting dialysis therapy, then at six and 12 months after starting dialysis. Discussion The results of this study may guide the choice of dialysis modality in the first year of treatment. It may also lead to a larger study prospectively assessing the effect of dialysis modality on cardiovascular morbidity and mortality. Trial Registration ACTRN12609000049279

  7. Arterial Stiffness Alterations and Inflammatory Response Following Endovascular Aortic Repair: Based on a Presentation at the 2013 VEITH Symposium, November 19-23, 2013 (New York, NY, USA).

    Science.gov (United States)

    Moulakakis, Konstantinos G; Mylonas, Spyridon N; Kakisis, John; Kadoglou, Nikolaos P E; Papadakis, Ioannis; Sfyroeras, George S; Antonopoulos, Constantine C N; Mantas, George; Ikonomidis, Ignatios; Liapis, Christos D

    2015-04-01

    Endovascular abdominal aortic aneurysm repair (EVAR) and thoracic aortic aneurysm repair (TEVAR) have been widely incorporated into clinical practice. However, changes in arterial stiffness and post-implantation syndrome after aortic endografting remain important issues under investigation. The aneurysm sac wall motion after successful EVAR and TEVAR reflects complex interactions between all the components of the excluded aneurysm, including true compliance of the aneurysm wall itself, intra-aneurysm sac pressure, remodeling of the thrombus, and mechanical characteristics of the endograft. Experimental and clinical studies have shown that aortic endografting results in increased arterial stiffness in animal models. It can be assumed that the alterations of aortic mechanical properties can have a direct impact on heart output. The long-term impact of these mechanical changes on cardiovascular outcomes and the potential effects of different endografts on hemodynamics are important issues under investigation. Post-implantation syndrome (PIS) is a systemic inflammatory response frequently observed after endovascular treatment of aortic pathologies. The main features of PIS include fever, leukocytosis, elevated C-reactive protein levels, and coagulation disturbances. Endograft design appears to influence this inflammatory response following aortic endografting; woven polyester endografts have been shown to be associated with greater inflammatory response compared to PTFE stent grafts. The purpose of this paper is to review the literature to elucidate arterial stiffness alterations and inflammatory response after EVAR and TEVAR and the impact of endograft design on aortic stiffness and the post-inflammatory response.

  8. Digital image correlation for full-field time-resolved assessment of arterial stiffness

    Science.gov (United States)

    Campo, Adriaan; Soons, Joris; Heuten, Hilde; Ennekens, Guy; Goovaerts, Inge; Vrints, Christiaan; Lava, Pascal; Dirckx, Joris

    2014-01-01

    Pulse wave velocity (PWV) of the arterial system is a very important parameter to evaluate cardiovascular health. Currently, however, there is no golden standard for PWV measurement. Digital image correlation (DIC) was used for full-field time-resolved assessment of displacement, velocity, acceleration, and strains of the skin in the neck directly above the common carotid artery. By assessing these parameters, propagation of the pulse wave could be tracked, leading to a new method for PWV detection based on DIC. The method was tested on five healthy subjects. As a means of validation, PWV was measured with ultrasound (US) as well. Measured PWV values were between 3.68 and 5.19 m/s as measured with DIC and between 5.14 and 6.58 m/s as measured with US, with a maximum absolute difference of 2.78 m/s between the two methods. DIC measurements of the neck region can serve as a test base for determining a robust strategy for PWV detection, they can serve as reference for three-dimensional fluid-structure interaction models, or they may even evolve into a screening method of their own. Moreover, full-field, time-resolved DIC can be adapted for other applications in biomechanics.

  9. Adesão ao tratamento e controle da pressão arterial por meio da monitoração ambulatorial de 24 horas Blood pressure treatment adherence and control through 24-hour ambulatory monitoring

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    Guilherme Brasil Grezzana

    2013-04-01

    Full Text Available FUNDAMENTO: A hipertensão arterial sistêmica (HAS é um importante fator de risco cardiovascular, no entanto os níveis de controle pressórico persistem inadequados. A avaliação da adesão ao tratamento anti-hipertensivo com a utilização da monitoração ambulatorial da pressão arterial (MAPA de 24 horas pode representar um importante auxílio na busca de metas de controle da HAS. OBJETIVO: Avaliar a adesão ao tratamento anti-hipertensivo e a sua relação com os valores de PA obtidos pela MAPA de 24 horas entre pacientes hipertensos de centros de atenção primária à saúde (APS. MÉTODOS: Estudo transversal com 143 pacientes hipertensos de amostra representativa de serviço de APS do município de Antônio Prado, RS. Foi realizada aplicação do teste de Morisky e Green para avaliar a aderência ao tratamento e a verificação do número de medicamentos utilizados, seguida pela aplicação da MAPA de 24 horas. RESULTADOS: Observou-se que 65,7% da amostra foram considerados aderentes ao tratamento proposto, 20,3% eram moderadamente aderentes, enquanto somente 14% foram classificados como não aderentes. Do total de 143 pacientes avaliados, 79 (55,2% foram identificados como HAS controlada (130/80 mmHg, 103 (72% apresentaram ausência de descenso noturno da PA e 60 (41,9% não estavam controlados durante o período de vigília. CONCLUSÃO: Verificamos, no presente estudo, que não há um controle adequado da HAS, com consequente perda de oportunidade dos profissionais envolvidos na APS de ajuste adequado das metas de PA preconizados. Esse fato ocorre a despeito de apropriada adesão ao tratamento anti-hipertensivo dos pacientes vinculados ao ambulatório de APS.BACKGROUND: Although systemic arterial hypertension (SAH is an important cardiovascular risk factor, blood pressure level control often remains inadequate. Assessment of adherence to antihypertensive treatment through 24-hour ambulatory blood pressure monitoring (ABPM may

  10. Effect of aliskiren on arterial stiffness, compared with ramipril in patients with mild to moderate essential hypertension

    Institute of Scientific and Technical Information of China (English)

    GUO Jian-qiang; WANG Hong-yi; SUN Ning-ling

    2013-01-01

    Background Aliskiren is a novel blood pressure-lowering agent acting as an oral direct renin inhibitor.The aim of this study was to assess the effect of aliskiren on arterial stiffness,compared with that of ramipril in mild to moderate essential hypertensive patients.Methods Following a two week placebo run-in period,patients with a mean sitting diastolic blood pressure (ms-DBP) >95 and <110 mmHg (1 mmHg=0.133 kPa),and a mean sitting systolic blood pressure (ms-SBP) <180 mmHg were randomly allocated to treatment with aliskiren (150 mg/d,n=20) or ramipril (5 mg/d,n=20) for eight weeks.Blood pressure,plasma renin activity,and the brachial-ankle pulse wave velocity (ba-PWV) were measured before and after eight weeks of treatment.Results Eight weeks of treatment significantly decreased systolic blood pressure and diastolic blood pressure in both the aliskiren group and ramipril group.The hypotensive effect did not differ between the two groups.Plasma renin activity decreased after aliskiren treatment and increased after ramipril treatment.There was no significant difference in baseline ba-PWV between the aliskiren and ramipril groups (P=-0.892).The ba-PWV was significantly reduced in both the aliskiren group (1535 (1405-1666) vs.1464 (1360-1506) cm/s) (P <0.01) and the ramipril group (1544 (1433-1673) vs.1447 (1327-1549) cm/s) (P <0.01).No statistically significant difference was found in the decline of ba-PWV between the two groups (P=0.766).Conclusions The current study revealed that aliskiren (150 mg/d) could ameliorate arterial stiffness and its effect was similar to ramipril (5 mg/d) in mild to moderate hypertensive patients,indicating that in addition to lowering blood pressure,aliskiren had beneficial effect on vascular protection.

  11. Is arterial stiffness in HIV-infected individuals associated with HIV-related factors?

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    Monteiro, P. [Serviço de Doenças Infecciosas, Faculdade de Medicina, Universidade de Pernambuco, Recife, PE (Brazil); Miranda-Filho, D.B. [Departamento de Medicina Clínica, Faculdade de Medicina, Universidade de Pernambuco, Recife, PE (Brazil); Bandeira, F. [Serviço de Endocrinologia, Faculdade de Medicina, Universidade de Pernambuco, Recife, PE (Brazil); Lacerda, H.R. [Departamento de Medicina Clínica, Faculdade de Medicina, Universidade de Pernambuco, Recife, PE (Brazil); Departamento de Medicina Tropical, Faculdade de Medicina, Universidade Federal de Pernambuco, Recife, PE (Brazil); Chaves, H. [Departamento de Cardiologia, Faculdade de Medicina, Universidade Federal de Pernambuco, Recife, PE (Brazil); Albuquerque, M.F.P.M. [Centro de Pesquisa Aggeu Magalhães,FIOCRUZ, Recife, PE (Brazil); Montarroyos, U.R. [Departamento de Medicina Tropical, Faculdade de Medicina, Universidade Federal de Pernambuco, Recife, PE (Brazil); Ximenes, R.A.A. [Departamento de Medicina Clínica, Faculdade de Medicina, Universidade de Pernambuco, Recife, PE (Brazil); Departamento de Medicina Tropical, Faculdade de Medicina, Universidade Federal de Pernambuco, Recife, PE (Brazil)

    2012-07-13

    We investigated the association between pulse wave velocity (PWV) and HIV infection, antiretroviral treatment-related characteristics, viral load, immune status, and metabolic changes in a cross-sectional study nested in a cohort of HIV/AIDS patients who have been followed for metabolic and cardiovascular changes since 2007. The study included patients recruited from the cohort (N = 261) and a comparison group (N = 82) of uninfected individuals, all enrolled from April to November 2009. Aortic stiffness was estimated using the carotid-femoral PWV (Complior-Artech, Paris, France). The groups were similar with respect to age, metabolic syndrome, diabetes mellitus, Framingham score, and use of antihypertensive and hypolipidemic medications. Hypertension was more frequent among the controls. Individuals with HIV had higher triglyceride, glucose and HDL cholesterol levels. Among individuals with HIV/AIDS, those with a nadir CD4{sup +} T-cell count <200 cells/mm{sup 3} had a higher PWV (P = 0.01). There was no statistically significant difference when subjects were stratified by gender. Heart rate, age, male gender, and blood pressure were independently correlated with PWV. Nadir CD4{sup +} T-cell count did not remain in the final model. There was no significance difference in PWV between HIV-infected individuals and uninfected controls. PWV was correlated with age, gender, and blood pressure across the entire population and among those infected with HIV. We recommend cohort studies to further explore the association between inflammation related to HIV infection and/or immune reconstitution and antiretroviral use and PWV.

  12. Effect of Aerobic Training on Cognitive Function and Arterial Stiffness in Sedentary Young Adults: A Pilot Randomized Controlled Trial

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    Samuel Asamoah

    2013-01-01

    Full Text Available This study measured cognitive and vascular responses to aerobic training in sedentary young adults. Ten adults (6 women, 4 men; 18–29 years were randomly assigned to an experimental or no-treatment control group. The experimental group engaged in a 6-week intervention, performed on exercise cycle and treadmill, 3x/week, 50 min/session; intensity was increased over time. Outcome measures included arterial stiffness (augmentation index, AIx, and pulse pressure, cardiorespiratory fitness (, and cognitive function (attention, processing speed, working memory, episodic memory, and executive function. Participants randomized to aerobic training improved processing speed versus control (, ES = 0.55. However, no group × time effects were noted in other domains of cognitive function. AIx was reduced by approximately 16% from before to after intervention in the experimental group; however, the improvement was not statistically significant versus control (, ES = 0.22. Pulse pressure did not change between groups over time (, ES = 0.0. increased by approximately 10% in the experimental group; however, the change was not significant between groups over time (, ES = 0.27. Vascular and cognitive adaptations to aerobic training may move in parallel. Robust trials simultaneously investigating a broad spectrum of aerobic training interventions and vascular and cognitive outcomes are warranted.

  13. Pentraxin 3 Is a Predictor for Fibrosis and Arterial Stiffness in Patients with Nonalcoholic Fatty Liver Disease

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    Kadir Ozturk

    2016-01-01

    Full Text Available Objective. The aim of the present study was to investigate whether pentraxin 3 (PTX3 can be a new noninvasive marker for prediction of liver fibrosis in patients with NAFLD. We also aimed to evaluate the relationship between PTX3 and atherosclerosis in patients with NAFLD. Method. Fifty-four male patients with biopsy-proven NAFLD and 20 apparently healthy male volunteers were included. PTX3 levels were determined, using an ELISA method (R&D Sysytems, Quantikine ELISA, USA. To detect the presence of subclinical atherosclerosis in NAFLD, measurements of CIMT, FMD, and cf-PWV levels were performed. Results. PTX3 levels in NAFLD patients with fibrosis were higher than both NAFLD patients without fibrosis and controls (P=0.032 and P=0.028, respectively, but there was no difference between controls and NAFLD patients without fibrosis in terms of PTX3 levels (P=0.903. PTX3 levels were strongly correlated with cf-PWV (r=0.359, P=0.003, whereas no significant correlation was found with other atherosclerosis markers, CIMT and FMD. Conclusion. Elevated plasma PTX3 levels are associated with the presence of fibrosis in patients with NAFLD, independently of metabolic syndrome components. This study demonstrated that for the first time there is a close association between elevated PTX3 levels and increased arterial stiffness in patients with NAFLD.

  14. Verapamil COER-24 180/240mg na hipertensão arterial leve a moderada em dose única diária avaliado pela monitorização ambulatorial da pressão arterial Single daily dose of verapamil (COER-24 180/240mg in mild and moderate hypertension evaluated by ambulatory blood pressure monitoring

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    Katia Coelho Ortega

    2000-03-01

    Full Text Available OBJETIVO: Avaliar a eficácia terapêutica do verapamil COER-24 180/240 mg, em dose única, ao deitar, como monoterapia para a hipertensão arterial leve a moderada. MÉTODOS: Estudo multicêntrico, aberto, não comparativo com 81 pacientes de ambos os sexos, com idade >20 anos e hipertensão arterial essencial leve e moderada. Medimos a pressão arterial no consultório e com a monitorização ambulatorial (MAPA durante 24h antes e ao final de 8 semanas do uso da medicação. RESULTADOS: Verificou-se diminuição (pOBJECTIVE: To evaluate the anti-hypertensive effecft of verapamil COER-24 180/240 mg in a single dose at bedtime as single therapy in mild to moderate hypertensives. METHODS: A multicentric, open, placebo controlled study of 81 hypertensive patients older than 20 years-old followed to 8 weeks. Blood pressure was measured in doctor's office and by 24h ambulatory monitoring (ABPM. RESULTS: We observed a decreased in systolic and diastolic blood pressure in doctor's office at 4th and 8th weeks. ABPM showed that both systolic, diastolic and mean blood pressure, heart rate and the mean 24-hour blood pressure load decreased after the 8-week treatment. In addition, there was a reduction of the double-product, especially in the morning and 68% of the patients didn't have any adverse events. CONCLUSION: The theraphy verapamil COER-24 180/240mg in a single dose is useful for mild and moderate hypertensive patients, with significant pressure decrease in both office blood pressure measurements and in the ABPM/24 hours, as well as showing good tolerability.

  15. Vitamin D Status in Rheumatoid Arthritis: Inflammation, Arterial Stiffness and Circulating Progenitor Cell Number.

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    Alberto Lo Gullo

    Full Text Available Suboptimal vitamin D status was recently acknowledged as an independent predictor of cardiovascular diseases and all-cause mortality in several clinical settings, and its serum levels are commonly reduced in Rheumatoid Arthritis (RA. Patients affected by RA present accelerated atherosclerosis and increased cardiovascular morbidity and mortality with respect to the general population. In RA, it has been reported an impairment of the number and the activity of circulating proangiogenic haematopoietic cells (PHCs, including CD34+, that may play a role in endothelial homeostasis. The purpose of the study is to investigate the association between vitamin D levels and PHCs, inflammatory markers, and arterial stiffening in patients with RA.CD34+ cells were isolated from 27 RA patients and 41 controls. Vitamin D levels, C-reactive protein (CRP, fibrinogen, pulse wave velocity (PWV, and carotid intima-media thickness (cIMT were also evaluated. CD34+ count and vitamin D levels were lower in RA patients as compared to controls, while fibrinogen, CRP, PWV and cIMT were higher in RA patients. CD34+ cell number appeared to be associated with vitamin D levels, and negatively correlated to fibrinogen and early atherosclerosis markers (PWV and cIMT; vitamin D levels appear also to be inversely associated to fibrinogen.RA patients with moderate disease activity presented with low vitamin D levels, low CD34+ cell count, increased PWV and cIMT; we found that vitamin D deficiency is associated to CD34+ cell reduction in peripheral blood, and with fibrinogen levels. This suggests that vitamin D might contribute to endothelial homeostasis in patients with RA.

  16. Sex differences in associations between insulin resistance, heart rate variability, and arterial stiffness in healthy women and men: a physiology study.

    Science.gov (United States)

    Rannelli, Luke Anthony; MacRae, Jennifer M; Mann, Michelle C; Ramesh, Sharanya; Hemmelgarn, Brenda R; Rabi, Doreen; Sola, Darlene Y; Ahmed, Sofia B

    2016-11-02

    Diabetes confers greater cardiovascular risk to women than to men. Whether insulin-resistance-mediated risk extends to the healthy population is unknown. Measures of insulin resistance (fasting insulin, homeostatic model assessment, hemoglobin A1c, quantitative insulin sensitivity check index, glucose) were determined in 48 (56% female) healthy subjects. Heart rate variability (HRV) was calculated by spectral power analysis and arterial stiffness was determined using noninvasive applanation tonometry. Both were measured at baseline and in response to angiotensin II infusion. In women, there was a non-statistically significant trend towards increasing insulin resistance being associated with an overall unfavourable HRV response and increased arterial stiffness to the stressor, while men demonstrated the opposite response. Significant differences in the associations between insulin resistance and cardiovascular physiological profile exist between healthy women and men. Further studies investigating the sex differences in the pathophysiology of insulin resistance in cardiovascular disease are warranted.

  17. Reduction of plasma aldosterone and arterial stiffness in obese pre- and stage1 hypertensive subjects after aerobic exercise

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    Collier, SR; Sandberg, K; Moody, AM; Frechette, V; Curry, CD; Ji, H; Gowdar, R; Chaudhuri, D; Meucci, M

    2017-01-01

    Obesity-related hypertension is associated with increased activity of the renin-angiotensin-aldosterone system (RAAS), increasing arterial stiffness. Aerobic exercise decreases pulse wave velocity (PWV), therefore a treatment option for hypertension and obesity. Assess RAAS activity and PWV before and after 4 weeks of aerobic training in unmedicated, pre-to-stage-1 hypertensives. Ten obese subjects (52±3.2 years, body mass index=33.5±1.4) performed 30 min of aerobic exercise on a treadmill 3 days per week at 65% of peak oxygen consumption (VO2peak). Descriptive characteristics, systolic and diastolic blood pressure (SBP and DBP), PWV, and a blood draw was performed at baseline, following the 4-week control and training interventions. No differences in descriptive characteristics during the control period were observed, however, a significant decrease in plasma aldosterone (ALDO) (255.4±75 to 215.8±66 pg ml−1, P=0.001), SBP (140±12 to 136±10.4 mm Hg; P=0.02), DBP (89±4.2 to 85±6.3 mm Hg; P =0.03) and central PWV (11.2±0.6 to 9.8±0.8 m s−1; P=0.04) was shown pre-to-post exercise training. Four weeks of moderate-intensity aerobic training in obese, hypertensives decreases plasma ALDO independently of body weight and is significantly correlated to decreases in PWV reductions. PMID:24785976

  18. Relationship between resistant hypertension and arterial stiffness assessed by brachial-ankle pulse wave velocity in the older patient

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    Chung CM

    2014-09-01

    Full Text Available Chang-Min Chung,1,2 Hui-Wen Cheng,2 Jung-Jung Chang,2 Yu-Sheng Lin,2 Ju-Feng Hsiao,2 Shih-Tai Chang,1 Jen-Te Hsu2,31School of Traditional Chinese Medicine, College of Medicine, Chang Gung University, 2Division of Cardiology, Chang Gung Memorial Hospital, Chiayi, 3Department of Medicine, College of Medicine, Chang Gung University, Taoyuan County, TaiwanBackground: Resistant hypertension (RH is a common clinical condition associated with increased cardiovascular mortality and morbidity in older patients. Several factors and conditions interfering with blood pressure (BP control, such as excess sodium intake, obesity, diabetes, older age, kidney disease, and certain identifiable causes of hypertension are common in patients resistant to antihypertensive treatment. Arterial stiffness, measured by brachial-ankle pulse wave velocity (baPWV, is increasingly recognized as an important prognostic index and potential therapeutic target in hypertensive patients. The aim of this study was to determine whether there is an association between RH and arterial stiffness. Methods: This study included 1,620 patients aged ≥65 years who were referred or self-referred to the outpatient hypertension unit located at a single cardiovascular center. They were separated into normotensive, controlled BP, and resistant hypertension groups. Home BP, blood laboratory parameters, echocardiographic studies and baPWV all were measured. Results: The likelihood of diabetes mellitus was significantly greater in the RH group than in the group with controlled BP (odds ratio 2.114, 95% confidence interval [CI] 1.194–3.744, P=0.010. Systolic BP was correlated in the RH group significantly more than in the group with controlled BP (odds ratio 1.032, 95% CI 1.012–1.053, P=0.001. baPWV (odds ratio 1.084, 95% CI 1.016–1.156, P=0.015 was significantly correlated with the presence of RH. The other factors were negatively correlated with the existence of RH.Conclusion: In

  19. Comparação e correlação entre automedida, medida casual e monitorização ambulatorial da pressão arterial

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    Weimar Kunz Sebba Barroso de Souza

    2011-08-01

    Full Text Available FUNDAMENTO: A medida casual da pressão arterial (PA pelos profissionais de saúde está sujeita a uma grande variabilidade, sendo necessário buscar novos métodos que possam superar essa limitação. OBJETIVO: Comparar e avaliar a correlação entre os níveis de PA obtidos por meio da automedida da pressão arterial (AMPA com a medida casual e com a monitorização ambulatorial da pressão arterial (MAPA. MÉTODOS: Avaliamos hipertensos que realizaram as três metodologias de medida da PA com intervalo menor que 30 dias; as médias das pressões foram utilizadas para comparação e correlação. Foram empregados os aparelhos: OMRON 705 CP (medida casual, OMRON HEM 714 (AMPA e SPACELABS 9002 (MAPA. RESULTADOS: Foram avaliados 32 pacientes, 50,09% mulheres, idade média 59,7 (± 11,2 anos, média do IMC 26,04 (± 3,3 kg/m². Valores médios de pressão sistólica (PAS e pressão diastólica (PAD para a AMPA foram de 134 (± 15,71mmHg e 79,32 (± 12,38 mmHg. Na medida casual as médias da PAS e PAD foram, respectivamente, 140,84 (± 16,15mmHg e 85 (± 9,68 mmHg. Os valores médios da MAPA na vigília foram 130,47 (± 13,26 mmHg e 79,84 (± 9,82 mmHg para PAS e PAD, respectivamente. Na análise comparativa, a AMPA apresentou valores semelhantes aos da MAPA (p > 0,05 e diferentes da medida casual (p < 0,05. Na análise de correlação a AMPA foi superior à medida casual, considerando a MAPA como o padrão de referência nas medidas tensionais. CONCLUSÃO: A AMPA apresentou melhor comparação com a MAPA do que a medida casual e também se correlacionou melhor com a aquela, especialmente para a pressão diastólica, devendo ser considerada uma alternativa com baixo custo para o acompanhamento do paciente hipertenso.

  20. FGF-23/Vitamin D Axis in Type 1 Diabetes: The Potential Role of Mineral Metabolism in Arterial Stiffness.

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    Gemma Llauradó

    Full Text Available To investigate the usefulness of Fibroblast Growth Factor 23 (FGF-23 and vitamin D as possible biomarkers of pre-clinical atherosclerosis, assessed as arterial stiffness (AS, in a group of subjects with type 1 diabetes (T1DM and no previous cardiovascular events.68 T1DM patients and 68 age- and sex-matched controls were evaluated for 1 age, sex, diabetes duration, physical activity, smoking, alcohol intake, BMI, blood pressure, fasting plasma glucose, HbA1c, estimated glomerular filtration rate (eGFR and lipid profile; 2 microvascular complications; 3 blood concentrations of FGF-23 and mineral metabolism parameters (calcium, phosphate, parathyroid hormone (PTH and 25-hydroxy-vitamin D (25(OHD; 4 AS, assessed as aortic pulse wave velocity (aPWV; and 5 low-grade inflammation (hsCRP, IL-6, sTNFαR1, sTNFαR2 and endothelial dysfunction (ED markers (ICAM-1, VCAM-1, E-Selectin.Patients with T1DM had higher aPWV compared with controls (p<0.001, but they did not present differences in 25(OHD (70.3(50.4-86.2nmol/L vs. 70.7(59.7-83.0nmol/L; p = 0.462 and in FGF-23 plasma concentrations (70.1(38.4-151.9RU/mL vs. 77.6(51.8-113.9RU/mL; p = 0.329. In T1DM patients, higher concentrations of FGF-23 were positively associated with aPWV after adjusting for eGFR and classical cardiovascular risk factors (model 1: ß = 0.202, p = 0.026, other mineral metabolism parameters (model 2: ß = 0.214, p = 0.015, microvascular complications, low-grade inflammation and ED markers (model 3: ß = 0.170, p = 0.045. Lower 25(OHD concentrations were also associated with higher aPWV after adjusting for all the above-mentioned factors (model 3: ß = -0.241, p = 0.015.We conclude that both FGF-23 plasma concentrations (positively and 25(OHD serum concentrations (negatively are associated with AS in patients with T1DM and no previous cardiovascular events.

  1. Reprodutibilidade da medida ambulatorial da pressão arterial em pacientes hipertensos com diabete melito tipo 2 Reproducibility of ambulatory blood pressure monitoring in hypertensive patients with type 2 diabetes mellitus

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    João Soares Felício

    2007-02-01

    Full Text Available OBJETIVO: Avaliar a reprodutibilidade e o efeito placebo sobre a monitorização ambulatorial da pressão arterial (MAPA (SpaceLabs-90207. MÉTODOS: Mensurou-se a PA no consultório e por meio de duas MAPA, realizadas em um intervalo de 1 a 10 meses (média de 4,9 meses, de 26 pacientes com diabetes tipo 2 e hipertensão. Onze pacientes (G1 realizaram as duas MAPA sem medicação anti-hipertensiva por 15 dias, enquanto o G2 (N = 15 fez a segunda MAPA em uso de placebo pelo mesmo período. RESULTADOS: Ao avaliarmos os coeficientes de variação (CV da PA sistólica na vigília (PASV, PA diastólica na vigília (PADV, PA sistólica nas 24h (PAS24h e PA diastólica nas 24h (PAD24h, encontramos valores de 4,6%, 3,9%, 5,0% e 4,0% no G1 e 4,3%, 5,1%, 3,7% e 5,1% no G2, respectivamente. Quanto ao CV da PA sistólica e diastólica durante o sono (PASS e PADS, encontramos 7,7% e 8,2% para G1, e 5,6% e 6,3% para G2, respectivamente. O CV da freqüência cardíaca na vigília e durante o sono foram: G1 = 5,9% e 9,0%, G2 = 6,9% e 5,8%, respectivamente. Analisando o total dos pacientes, todas as variáveis mostraram fortes correlações entre a primeira e a segunda MAPA (PASV, r=0,76; POBJECTIVE: To evaluate the reproducibility of ambulatory blood pressure monitoring (ABPM (SpaceLabs-90207 and placebo effect on ABPM. METHODS: Blood pressure was measured in the office and over two ABPM periods with an interval from one to ten months (mean 4.9 months, in 26 patients with type 2 diabetes mellitus and hypertension. Eleven patients (G1 had two ABPMs without taking antihypertensive drugs for 15 days, whereas G2 (N=15 had the second ABPM after administration of a placebo for 15 days. RESULTS: In the evaluation of the coefficient of variation (CV of diurnal (awake systolic BP (DSBP, of diurnal (awake diastolic BP (DDBP, of 24-hour systolic BP (24hSBP and of 24-hour diastolic BP (24hDBP, the values found were 4.6%, 3.9%, 5.0%, 4.0% for G1 and 4.3%, 5.1%, 3.7%, 5

  2. Adesão ao tratamento e controle da pressão arterial por meio da monitoração ambulatorial de 24 horas

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    Guilherme Brasil Grezzana

    2013-04-01

    Full Text Available FUNDAMENTO: A hipertensão arterial sistêmica (HAS é um importante fator de risco cardiovascular, no entanto os níveis de controle pressórico persistem inadequados. A avaliação da adesão ao tratamento anti-hipertensivo com a utilização da monitoração ambulatorial da pressão arterial (MAPA de 24 horas pode representar um importante auxílio na busca de metas de controle da HAS. OBJETIVO: Avaliar a adesão ao tratamento anti-hipertensivo e a sua relação com os valores de PA obtidos pela MAPA de 24 horas entre pacientes hipertensos de centros de atenção primária à saúde (APS. MÉTODOS: Estudo transversal com 143 pacientes hipertensos de amostra representativa de serviço de APS do município de Antônio Prado, RS. Foi realizada aplicação do teste de Morisky e Green para avaliar a aderência ao tratamento e a verificação do número de medicamentos utilizados, seguida pela aplicação da MAPA de 24 horas. RESULTADOS: Observou-se que 65,7% da amostra foram considerados aderentes ao tratamento proposto, 20,3% eram moderadamente aderentes, enquanto somente 14% foram classificados como não aderentes. Do total de 143 pacientes avaliados, 79 (55,2% foram identificados como HAS controlada (130/80 mmHg, 103 (72% apresentaram ausência de descenso noturno da PA e 60 (41,9% não estavam controlados durante o período de vigília. CONCLUSÃO: Verificamos, no presente estudo, que não há um controle adequado da HAS, com consequente perda de oportunidade dos profissionais envolvidos na APS de ajuste adequado das metas de PA preconizados. Esse fato ocorre a despeito de apropriada adesão ao tratamento anti-hipertensivo dos pacientes vinculados ao ambulatório de APS.

  3. Estimated aortic blood pressure based on radial artery tonometry underestimates directly measured aortic blood pressure in patients with advancing chronic kidney disease staging and increasing arterial stiffness.

    Science.gov (United States)

    Carlsen, Rasmus K; Peters, Christian D; Khatir, Dinah S; Laugesen, Esben; Bøtker, Hans Erik; Winther, Simon; Buus, Niels H

    2016-10-01

    Central blood pressure (BP) can be assessed noninvasively based on radial tonometry and may potentially be a better predictor of clinical outcome than brachial BP. However, the validity of noninvasively obtained estimates has never been examined in patients with chronic kidney disease (CKD). Here we compared invasive aortic systolic BP (SBP) with estimated central SBP obtained by radial artery tonometry and examined the influence of renal function and arterial stiffness on this relationship. We evaluated 83 patients with stage 3 to 5 CKD (mean estimated glomerular filtration rate [eGFR] 30 ml/min/1.73 m(2)) and 41 controls without renal disease undergoing scheduled coronary angiography. BP in the ascending aorta was measured through the angiography catheter and simultaneously estimated using radial tonometry. The mean difference between estimated central and aortic SBP was -13.2 (95% confidence interval -14.9 to -11.4) mm Hg. Arterial stiffness was evaluated by carotid-femoral pulse wave velocity (cf-PWV) and was significantly increased in CKD patients compared with (versus) control patients (mean 10.7 vs. 9.3 m/s). The difference in BP significantly increased 1.0 mm Hg for every 10 ml/min decrease in eGFR and by 1.6 mm Hg per 1 m/s increase in cfPWV. Using multivariate regression analysis including both eGFR and cfPWV, the difference between estimated central and invasive aortic SBP was significantly increased by 0.7 mm Hg. For the entire cohort brachial SBP significantly better reflected invasive SBP than estimated SBP. Thus, tonometry-based estimates of central BP progressively underestimate invasive central SBP with decreasing renal function and increasing arterial stiffness in CKD patients.

  4. Society for Ambulatory Anesthesia

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    ... We Represent Ambulatory and Office-Based Anesthesia The Society for Ambulatory Anesthesia provides educational opportunities, encourages research ... 6620 | E-mail: info@sambahq.org Copyright | 2016 Society for Ambulatory Anesthesia Home | Search | Terms | Privacy Policy | ...

  5. Reproducibility of arterial stiffness and wave reflections in chronic obstructive pulmonary disease: the contribution of lung hyperinflation and a comparison of techniques.

    Science.gov (United States)

    Stone, Ian S; John, Leonette; Petersen, Steffen E; Barnes, Neil C

    2013-11-01

    Significant cardiovascular morbidity and mortality exists in chronic obstructive pulmonary disease (COPD). Arterial stiffness is raised in COPD and may be a mechanistic link. Non-invasive assessment of arterial stiffness has the potential to be a surrogate outcome measure, although no reproducibility data exists in COPD patients. Two studies (23 and 33 COPD patients) were undertaken to 1) assess the Vicorder reproducibility of carotid-femoral pulse wave velocity and Augmentation index in COPD; 2) compare it to SphygmoCor; and 3) assess the contribution of lung hyperinflation to measurement variability. There were excellent correlations and good agreement between repeat Vicorder measurements for carotid-femoral pulse wave velocity (r = 0.96 (p lung hyperinflation (as measured by residual volume percent predicted, total lung capacity percent predicted or the ratio of inspiratory capacity to residual volume) and variability of measurements in either study. In COPD, measurement of carotid-femoral pulse wave velocity is highly reproducible, not affected by lung hyperinflation and suitable as a surrogate endpoint in research studies. Day-to-day variation in augmentation index highlights the importance of such studies prior to the planning and undertaking of clinical COPD research.

  6. Peripheral Endothelial (DysFunction, Arterial Stiffness and Carotid Intima-Media Thickness in Patients after Kawasaki Disease: A Systematic Review and Meta-Analyses.

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    Sanne M Dietz

    Full Text Available Kawasaki disease (KD is a systemic pediatric vasculitis. Its main complication is the development of coronary arterial aneurysms (CAA, causing an increased risk for ischemia and myocardial infarction. It is unclear whether KD patients, apart from the presence of CAA, have an increased cardiovascular disease (CVD risk due to the previous systemic vasculitis. The aim of this study was to systematically review and meta-analyse the literature regarding surrogate markers for CVD risk in KD patients.Medline and Embase were searched for articles comparing endothelial dysfunction (flow-mediated dilation, nitroglycerin-mediated dilation and peripheral arterial tonometry, vascular stiffness (stiffness index, pulse wave velocity and carotid intima-media thickness (cIMT between patients and controls. Two investigators assessed the articles for eligibility and evaluated quality.Thirty studies were included. For all outcomes, moderate to high heterogeneity between studies was found. Most studies reported a decreased flow-mediated dilation in the whole KD- and CAA-positive group compared to controls, while data on CAA-negative patients were conflicting. The stiffness index was increased in the majority of studies evaluating the whole KD- and CAA-positive group, but not in most studies on CAA-negative patients. Mean cIMT was neither significantly increased in the whole KD-group nor in the CAA-positive group nor in most studies studying CAA-negative patients. Studies measuring maximum cIMT were conflicting.Literature suggests that surrogate markers for CVD risk in KD patients are increased in CAA-positive but not in CAA-negative patients. This may indicate that CAA-positive patients should be monitored for CVD in later life. The results of this review have to be interpreted with care due to substantial heterogeneity between studies and methodological limitations, as well as the lack of long-term follow-up studies.

  7. Uncertainty quantification of inflow boundary condition and proximal arterial stiffness-coupled effect on pulse wave propagation in a vascular network.

    Science.gov (United States)

    Brault, Antoine; Dumas, Laurent; Lucor, Didier

    2016-12-10

    This work aims at quantifying the effect of inherent uncertainties from cardiac output on the sensitivity of a human compliant arterial network response based on stochastic simulations of a reduced-order pulse wave propagation model. A simple pulsatile output form is used to reproduce the most relevant cardiac features with a minimum number of parameters associated with left ventricle dynamics. Another source of significant uncertainty is the spatial heterogeneity of the aortic compliance, which plays a key role in the propagation and damping of pulse waves generated at each cardiac cycle. A continuous representation of the aortic stiffness in the form of a generic random field of prescribed spatial correlation is then considered. Making use of a stochastic sparse pseudospectral method, we investigate the sensitivity of the pulse pressure and waves reflection magnitude over the arterial tree with respect to the different model uncertainties. Results indicate that uncertainties related to the shape and magnitude of the prescribed inlet flow in the proximal aorta can lead to potent variation of both the mean value and standard deviation of blood flow velocity and pressure dynamics due to the interaction of different wave propagation and reflection features. Lack of accurate knowledge in the stiffness properties of the aorta, resulting in uncertainty in the pulse wave velocity in that region, strongly modifies the statistical response, with a global increase in the variability of the quantities of interest and a spatial redistribution of the regions of higher sensitivity. These results will provide some guidance in clinical data acquisition and future coupling of arterial pulse wave propagation reduced-order model with more complex beating heart models.

  8. Indirect measure of visceral adiposity ‘A Body Shape Index’ (ABSI) is associated with arterial stiffness in patients with type 2 diabetes

    Science.gov (United States)

    Bouchi, Ryotaro; Asakawa, Masahiro; Ohara, Norihiko; Nakano, Yujiro; Takeuchi, Takato; Murakami, Masanori; Sasahara, Yuriko; Numasawa, Mitsuyuki; Minami, Isao; Izumiyama, Hajime; Hashimoto, Koshi; Yoshimoto, Takanobu; Ogawa, Yoshihiro

    2016-01-01

    Objective Among indirect measures of visceral adiposity, A Body Shape Index (ABSI), which is defined as waist circumference (WC)/(body mass index (BMI)2/3×height1/2), is unique in that ABSI is positively correlated with visceral adiposity and is supposed to be independent of BMI. ABSI has been also shown to be linearly and positively associated with visceral fat mass and all-cause and cardiovascular disease (CVD) in the general population. It is, however, uncertain whether ABSI could be associated with arterial stiffness in patients with diabetes. Methods This is a cross-sectional study of 607 patients with type 2 diabetes (mean age 64±12 years; 40.0% female). Visceral fat area (VFA, cm2) and subcutaneous fat area (SFA, cm2) were assessed with a dual-impedance analyzer. In order to estimate the risk for CVD, brachial-ankle pulse wave velocity (baPWV, cm) was used for the assessment of arterial stiffness. Results ABSI was significantly and positively correlated with VFA (r=0.138, p=0.001) and negatively associated with BMI (r=−0.085, p=0.037). The correlation of z-score for ABSI with VFA remained significant (r=0.170, p<0.001) but not with BMI (r=0.009, p=0.820). ABSI (standardized β 0.095, p=0.043) but not WC (standardized β −0.060, p=0.200) was significantly and positively correlated with baPWV in the multivariate model including BMI as a covariate. Conclusions ABSI appears to reflect visceral adiposity independently of BMI and to be a substantial marker of arterial stiffening in patients with type 2 diabetes. PMID:27026809

  9. Sprint interval and traditional endurance training induce similar improvements in peripheral arterial stiffness and flow-mediated dilation in healthy humans.

    Science.gov (United States)

    Rakobowchuk, Mark; Tanguay, Sophie; Burgomaster, Kirsten A; Howarth, Krista R; Gibala, Martin J; MacDonald, Maureen J

    2008-07-01

    Low-volume sprint interval training (SIT), or repeated sessions of brief, intense intermittent exercise, elicits metabolic adaptations that resemble traditional high-volume endurance training (ET). The effects of these different forms of exercise training on vascular structure and function remain largely unexplored. To test the hypothesis that SIT and ET would similarly improve peripheral artery distensibility and endothelial function and central artery distensibility, we recruited 20 healthy untrained subjects (age: 23.3 +/- 2.8 yr) and had them perform 6 wk of SIT or ET (n = 5 men and 5 women per group). The SIT group completed four to six 30-s "all-out" Wingate tests separated by 4.5 min of recovery 3 days/wk. The ET group completed 40-60 min of cycling at 65% of their peak oxygen uptake (Vo2peak) 5 days/wk. Popliteal endothelial function, both relative and normalized to shear stimulus, was improved after training in both groups (main effect for time, P < 0.05). Carotid artery distensibility was not statistically altered by training (P = 0.29) in either group; however, popliteal artery distensibility was improved in both groups to the same degree (main effect, P < 0.05). We conclude that SIT is a time-efficient strategy to elicit improvements in peripheral vascular structure and function that are comparable to ET. However, alterations in central artery distensibility may require a longer training stimuli and/or greater initial vascular stiffness than observed in this group of healthy subjects.

  10. Arterial Stiffness by Aerobic Exercise Is Related with Aerobic Capacity, Physical Activity Energy Expenditure and Total Fat but not with Insulin Sensitivity in Obese Female Patients with Type 2 Diabetes

    OpenAIRE

    Ji Yeon Jung; Kyung Wan Min; Hee Jung Ahn; Hwi Ryun Kwon; Jae Hyuk Lee; Kang Seo Park; Kyung Ah Han

    2014-01-01

    Background Arterial stiffness is an important factor in atherosclerosis. Thus we examined whether aerobic exercise could reduce arterial stiffness in obese women with type 2 diabetes without diabetic complication. Methods A total of 35 women with type 2 diabetes (body mass index, 26.6±2.8 kg/m2; age, 56.4±1.9 years; duration of diabetes, 4.7±4.8 years) were assigned to aerobic exercise group (AEG) or control group (CG). AEG completed a 12-week exercise program (3.6 to 5.2 metabolic equivalent...

  11. Increased burden and severity of metabolic syndrome and arterial stiffness in treatment naïve HIV+ patients from Cameroon

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    Ngatchou W

    2013-09-01

    Full Text Available William Ngatchou,1 Daniel Lemogoum,1 Pierre Ndobo,2,† Euloge Yagnigni,2 Emiline Tiogou,2 Elisabeth Nga,2 Charles Kouanfack,2 Philippe van de Borne,1 Michel P Hermans3 1Hypertension Clinic, Erasme University Hospital, Brussels, Belgium; 2Department of Cardiology, Central Hospital, Yaoundé, Cameroon; 3Department of Endocrinology and Nutrition, Cliniques Universitaires St-Luc, Brussels, Belgium †Professor Pierre Ndobo passed away on January 21, 2013 Background: Human immunodeficiency virus (HIV and its therapy are associated with increased aortic stiffness and metabolic syndrome (MetS phenotype in Caucasian patients. We hypothesized that, independently of antiretroviral therapy, HIV infection in native black African patients is associated with increased burden of cardiometabolic risk factors that may accelerate arterial structural damage and translate into increased aortic stiffness. Patients and methods: Ninety-six apparently healthy Cameroonian subjects (controls were compared to 108 untreated Cameroonian HIV+ patients (HIV-UT of similar age. In each participant, pulse wave velocity (Complior, aortic augmentation index (SphygmoCor, brachial blood pressure (Omron 705 IT, fasting plasma glucose (FPG, and lipids were recorded, as well as the prevalence and severity of MetS, based on the American Heart Association/National Heart, Lung, and Blood Institute score ≥3/5. Results: Prevalence of impaired fasting glucose (FPG 100–125 mg · dL-1 and of diabetes (FPG > 125 mg · dL-1 was higher in HIV-UT than in controls (47% versus 27%, and 26% versus 1%, respectively; both P < 0.01. Fasting triglycerides and the atherogenic dyslipidemia ratio were significantly higher in HIV-UT than in controls. Hypertension prevalence was high and comparable in both groups (41% versus 44%, respectively; not significant. HIV-UT patients exhibited a twice-higher prevalence of MetS than controls (47% versus 21%; P = 0.02. Age- and sex-adjusted pulse wave velocity was

  12. 老年女性腹型肥胖与血压昼夜节律及动脉僵硬度的关系%Relationship of abdominal obesity with circadian blood pressure rhythm and arterial stiffness in elderly women

    Institute of Scientific and Technical Information of China (English)

    许建超; 刘振东; 路方红; 刁玉涛; 张华; 赵颖馨; 孙尚文; 王舒建

    2014-01-01

    Objective To study the relationship of abdominal obesity with circadian blood pressure rhythm and arterial stiffness in elderly women .Methods Three hundred and fifty-three elderly women were divided into non-abdominal obesity group (n= 160) and abdominal obesity group (n=193)according to their waist circumference .Their carotid radial pulse wave velocity(crPWV) and 24 h ambulatory blood pressure were monitored .Results The non-dipper blood pressure , crPWV and symmetric AASI were significantly higher in abdominal obesity group than in non-abdominal obesity group (32 .6% vs 10 .0% ,11 .83 ± 1 .19 m/s vs 10 .90 ± 1 .04 m/s ,0 .31 ± 0 .15 vs 0 .24 ± 0 .17 ,P<0 .05) wile the nocturnal systolic and diastolic blood pressure were significantly lower in abdominal obesity group than in non-abdominal obesity group (P<0 .01) .Multiple linear regression analysis showed that waist circumference was the main risk factor for crPWV and sym-metric AASI after adjustment for age ,blood lipid and BMI (P<0 .05) .Logistic regression analysis revealed that abdominal obesity was the main risk factor for circadian blood pressure rhythm (OR=1 .104 ,95% CI:1 .074 -1 .134 ,P<0 .05) .Conclusion Abdominal fat deposit can signifi-cantly affect circadian blood pressure rhythm and arterial stiffness in elderly women .It is of great importance to control waist circumference in preventing arteriosclerosis .%目的:探讨老年女性腹型肥胖与血压昼夜节律及动脉僵硬度的关系。方法选择老年女性353例,根据腰围将受试者分为2组,即非腹型肥胖组160例,腹型肥胖组193例。所有受试者监测颈桡动脉脉搏波传导速度(crPWV)、24 h动态血压。结果腹型肥胖组非杓型血压(32.6% vs 10.0%)、crPWV [(11.83±1.19)m/s vs (10.90±1.04)m/s]、对称动态动脉硬化指数[(0.31±0.15) vs (0.24±0.17)]显著高于非腹型肥胖组,夜间收缩压下降率、夜间舒张压下降率显著

  13. Sustained Improvement of Arterial Stiffness and Blood Pressure after Long-Term Rosuvastatin Treatment in Patients with Inflammatory Joint Diseases: Results from the RORA-AS Study.

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    Eirik Ikdahl

    Full Text Available Patients with inflammatory joint diseases (IJD have a high prevalence of hypertension and increased arterial stiffness. The aim of the present study was to evaluate the effect of long-term rosuvastatin treatment on arterial stiffness, measured by augmentation index (AIx and aortic pulse wave velocity (aPWV, and blood pressure (BP in IJD patients with established atherosclerosis.Eighty-nine statin naïve IJD patients with carotid atherosclerotic plaque(s (rheumatoid arthritis n = 55, ankylosing spondylitis n = 23, psoriatic arthritis n = 11 received rosuvastatin for 18 months to achieve low-density lipoprotein cholesterol goal ≤1.8 mmol/L. Change in AIx (ΔAIx, aPWV (ΔaPWV, systolic BP (ΔsBP and diastolic BP (ΔdBP from baseline to study end was assessed by paired samples t-tests. Linear regression was applied to evaluate associations between cardiovascular disease (CVD risk factors, rheumatic disease specific variables and medication, and ΔAIx, ΔaPWV, ΔsBP and ΔdBP.AIx, aPWV, sBP and dBP were significantly reduced from baseline to study end. The mean (95%CI changes were: ΔAIx: -0.34 (-0.03, -0.65% (p = 0.03, ΔaPWV: -1.69 (-0.21, -3.17m/s2 (p = 0.03, ΔsBP: -5.27 (-1.61, -8.93mmHg (p = 0.004 and ΔdBP -2.93 (-0.86, -5.00mmHg (p = 0.01. In linear regression models, ∆aPWV was significantly correlated with ΔsBP and ΔdBP (for all: p<0.001.There is an unmet need of studies evaluating CVD prevention in IJD patients. We have shown for the first time that long-term intensive lipid lowering with rosuvastatin improved arterial stiffness and induced a clinically significant BP reduction in patients with IJD. These improvements were linearly correlated and may represent novel insight into the pleiotropic effects by statins.ClinicalTrials.gov NCT01389388.

  14. Effects of neuromuscular electrical stimulation and aerobic exercise training on arterial stiffness and autonomic functions in patients with chronic heart failure.

    Science.gov (United States)

    Dobšák, Petr; Tomandl, Josef; Spinarova, Lenka; Vitovec, Jiri; Dusek, Ladislav; Novakova, Marie; Jarkovsky, Jiri; Krejci, Jan; Hude, Petr; Honek, Tomáš; Siegelova, Jarmila; Homolka, Pavel

    2012-10-01

    Neuromuscular electrical stimulation (NMES) of leg muscles has been introduced in clinical practice as a rehabilitation (RHB) method in patients with chronic heart failure (CHF); however, the role of NMES on the reduction of arterial stiffness and autonomic disbalance in these patients has not yet been studied. Sixty-one patients with stable CHF (mean age 58.9 [2.1] years; mean ejection fraction 31 [4.2]%, New York Heart Association II-III) were randomly assigned into two groups. Patients in (i) exercise training group (ET; n = 30) underwent 12 weeks of bicycle ET (3 × 40 min/week); (ii) group NMES (n = 31) performed 12 weeks of NMES of quadriceps and calf muscles (frequency 10 Hz, mode "20 s on-20 s off," intensity 60 mA), 2 × 60 min/day. Noninvasive assessment of arterial stiffness was done using the cardio-ankle vascular index (CAVI). CAVI and heart rate variability (HRV) and ·VO(2peak) were evaluated before and after RHB program. Both types of RHB reduced significantly CAVI (ET from 9.6 [0.2] to 8.9 [0.2], P < 0.012; NMES from 9.3 [0.2] to 8.7 [0.2], P < 0.013), increased high frequency (HF) component of HRV (+65.6%; P = 0.001) and decreased ratio of low frequency (LF) component with HF component (LF/HF ratio) in group ET (-39.8%; P < 0.001). Changes of HRV parameters in group NMES were not significant; however, a marked tendency to autonomic stabilization was present. Both types of RHB led also to significant increase of ·VO(2peak) (ET from 18.7 [0.7] to 20.8 [0.7] mL/kg/min, P < 0.004; NMES from 17.3 [0.7] to 19.0 [0.7] mL/kg/min, P < 0.001). ET or NMES has been shown to improve significantly arterial stiffness and to stabilize autonomic balance.

  15. School burnout: increased sympathetic vasomotor tone and attenuated ambulatory diurnal blood pressure variability in young adult women.

    Science.gov (United States)

    May, Ross W; Sanchez-Gonzalez, Marcos A; Fincham, Frank D

    2015-01-01

    Two studies examined autonomic and cardiovascular functioning that may link school burnout to cardiovascular risk factors in young healthy adult females. Study 1 (N = 136) investigated whether school burnout was related to resting values of blood pressure (BP) and blood pressure variability (BPV) through laboratory beat-to-beat BP assessment. Study 2 (N = 94) examined the link between school burnout and diurnal BPV through ambulatory BP monitoring. Controlling for anxiety and depressive symptomatology, school burnout demonstrated strong positive relationships with indices of cardiac sympathovagal tone, sympathetic vasomotor tone, inefficient myocardial oxygen consumption, increased 24-h ambulatory heart rate and BP, blunted BP diurnal variability, and increased arterial stiffness. These studies establish cardiovascular biomarkers of school burnout and suggest that even in a seemingly healthy sample school burnout may predispose females to increased cardiovascular risk. Several future lines of research are outlined.

  16. Vitamin D deficiency is associated with digital ulcer but not with atherosclerosis or arterial stiffness in patients with systemic sclerosis: a pilot study.

    Science.gov (United States)

    Park, Eun-Kyoung; Park, Ji-Heh; Kweon, Seong-Min; Kim, Geun-Tae; Lee, Seung-Geun

    2017-04-01

    The objective of this study was to investigate the association of vitamin D deficiency with digital ulcers (DUs) that result from microvasculopathy, carotid intima-media thickness (CIMT) as surrogate markers of atherosclerosis, and brachial-ankle pulse wave velocity (baPWV) representing arterial stiffness in patients with systemic sclerosis (SSc). In this cross-sectional study, 40 female SSc patients and 80 healthy controls matched for sex, age, and blood sampling season were recruited. Vitamin D deficiency was defined as serum 25-OHD levels D deficiency was more prevalent in SSc patients than in controls (30 vs. 11.3%). Regarding SSc patients, 9 (22.5%) had DUs ever, and the mean CIMT and baPWV were 0.68 mm and 1561.1 cm/s, respectively; carotid plaque was detected in 13 (34.2%) patients. The frequency of DUs ever was significantly higher for SSc patients with vitamin D deficiency than those without this feature (50 vs. 10.7%, p = 0.012), but the median CIMT and baPWV and the frequency of carotid plaque did not differ according to the presence of vitamin D deficiency. Multivariable logistic regression analysis showed that vitamin D deficiency was an independent risk factor for DUs ever (OR = 7.72, p = 0.024). Vitamin D deficiency was associated with DUs, but not with atherosclerosis or arterial stiffness, potentially indicating that vitamin D may have different effects on the microvascular and macrovascular involvement in SSc pathophysiology.

  17. Drug therapies and presence of coronary artery disease may affect aortic stiffness in Alzheimer’s disease

    Directory of Open Access Journals (Sweden)

    Bektaş O

    2015-02-01

    Full Text Available Osman Bektaş,1 Zeki Yüksel Günaydin,1 Ahmet Karagöz,2 Ahmet Kaya1 1Ordu University, Department of Cardiology, Ordu, 2Giresun University, Department of Cardiology, Giresun, TurkeyWe have read the original research entitled "Altered diastolic function and aortic stiffness in Alzheimer’s disease" by Çalık et al1 which was published in the July 2014 issue of Clinical Interventions in Aging, with great interest. We would like to touch on some points about this article.View original paper by Çalık and colleagues

  18. Arterial stiffness, as monitored by cardio–ankle vascular index, is affected by obstructive sleep apnea, blood glucose control, and body weight – a case with 8 years follow up

    Science.gov (United States)

    Shimizu, Kazuhiro; Yamamoto, Tomoyuki; Shirai, Kohji

    2016-01-01

    The cardio–ankle vascular index (CAVI) is an indicator of arterial stiffness from the heart to the ankles. The CAVI increases as arteriosclerosis progresses, but it can be decreased by appropriate treatment. There are several risk factors for coronary artery disease, however, the degree of stress caused by each separate risk factor to arteries cannot be assessed. CAVI increases with age and according to the severity of atherosclerosis. We found that CAVI also changes in response to the control of risk factors, which may be associated with the functional stiffness of arteries. CAVI can be a useful indicator of risk control for coronary artery disease. We followed a patient aged 71 years who had diabetes mellitus and obstructive sleep apnea (OSA) by measuring CAVI for 8 years from age 63. He underwent coronary artery bypass grafting due to angina pectoris when he was 63 years old. Before coronary artery bypass grafting, CAVI was 11.8 on the right and 11.5 on the left. Three years later he was found to have OSA and received treatment with continuous positive airway pressure. There was a marked improvement in CAVI after continuous positive airway pressure (age 68; right 10.4, left 10.2). However, following a gradual increase in body weight and worsening of diabetes mellitus, CAVI showed an increasing trend. CAVI decreased with biguanides treatment, but increased again with an increase in body weight. In conclusion, CAVI responded to the patient’s conditions including obesity, diabetes mellitus, and OSA. CAVI is not only a marker of arterial stiffness, but can also be a useful indicator of physiological status; it may be effective in total risk control for coronary artery disease. PMID:27563259

  19. High trans but not saturated fat beverage causes an acute reduction in postprandial vascular endothelial function but not arterial stiffness in humans.

    Science.gov (United States)

    Lane-Cordova, Abbi D; Witmer, Jordan R; Dubishar, Kaitlyn; DuBose, Lyndsey E; Chenard, Catherine A; Siefers, Kyle J; Myers, Janie E; Points, Lauren J; Pierce, Gary L

    2016-10-01

    A diet high in trans-fatty acids (TFAs) is associated with a higher risk of cardiovascular disease (CVD) than a diet high in saturated fatty acids (SFAs), but the mechanisms remain unclear. We hypothesized that a beverage high in TFAs would cause a larger reduction in postprandial endothelial function and an increase in arterial stiffness, in part from greater reductions in insulin sensitivity, compared with a beverage high in SFAs. Eleven healthy adults (aged 47±5 years) ingested a warm test beverage (520 kcal, 56 g total fat, 5 g carbohydrate, 1 g protein) high in either TFAs or SFAs in a randomized cross-over study. Ingestion of the beverage high in TFAs (phigh in SFAs (p=0.49) decreased endothelial function (brachial artery flow-mediated dilation, mmΔ) at 3-4 hours (phigh in TFAs but not SFAs results in a postprandial reduction in endothelial function and a trend for decreased insulin sensitivity, potentially explaining the higher risk of CVD with a diet high in TFAs.

  20. Baixo peso ao nascer como marcador de alterações na monitorização ambulatorial da pressão arterial Bajo peso al nacer como marcador de alteraciones en el monitoreo ambulatorio de la presión arterial Low birth weight as a marker of changes in ambulatory blood pressure monitoring

    Directory of Open Access Journals (Sweden)

    Cláudia Maria Salgado

    2009-02-01

    Full Text Available FUNDAMENTO: O baixo peso ao nascimento (BPN está associado com aumento da pressão arterial (PA e de doenças cardiovasculares no adulto. OBJETIVO: Avaliar as possíveis alterações na monitorização ambulatorial da pressão arterial (MAPA em crianças com BPN. MÉTODOS: Avaliou-se o peso ao nascimento (PN de 1.049 crianças, entre 8 e 11 anos, em escolas de Goiânia. Aquelas com BPN (PN 3,0 kg. O PN foi obtido no cartão da criança. Avaliaram-se PA casual e MAPA. Após a obtenção do peso e da estatura para cálculo do índice de massa corpórea (IMC, realizou-se avaliação da maturação sexual segundo os critérios de Tanner (excluídos Tanner >2. RESULTADOS: Obtiveram-se 34 crianças com BPN e 34 com PNN. Os grupos foram semelhantes quanto a idade, sexo, raça, peso, estatura, IMC e história familiar de hipertensão. As crianças com BPN apresentaram maior pressão sistólica (PS casual (p = 0,007. Na MAPA, apresentaram maior pressão diastólica (PD nas 24 horas (p = 0,009, maior PD de vigília (p = 0,002, maiores PS e PD no sono (p = 0,005 e p = 0,001 e menor descenso noturno da PS e PD (p = 0,001 do que as com PNN. Observou-se uma correlação positiva do PN com o descenso noturno da PS (p = 0,022 e negativa com a PS no sono (p = 0,032. CONCLUSÃO: As crianças com BPN apresentaram PA mais elevada e alteração do ritmo circadiano da pressão arterial, com atenuação do descenso noturno. Esses achados podem representar um risco aumentado para a hipertensão arterial e doença cardiovascular no adulto.FUNDAMENTO: El bajo peso al nacer (BPN está asociado al aumento de la presión arterial (PA y de enfermedades cardiovasculares en el adulto. OBJETIVO: Evaluar las posibles alteraciones en el monitoreo ambulatorio de la presión arterial (MAPA en niños con BPN. MÉTODOS: Se evaluó el peso al nacer (PN de 1.049 niños, entre 8 y 11 años, en escuelas de la ciudad de Goiânia. Aquellos con BPN (PN 3,0 kg. El PN se obtuvo en la tarjeta

  1. Monitorização ambulatorial da pressão arterial e risco cardiovascular em mulheres com hipertensão resistente Monitoreo ambulatorio de la presión Arterial y riesgo cardiovascular en mujeres con hipertensión resistente Ambulatory blood pressure monitoring and cardiovascular risk in resistant hypertensive women

    Directory of Open Access Journals (Sweden)

    Monica Maria Ferreira Magnanini

    2009-06-01

    Full Text Available FUNDAMENTO: Poucos estudos exploraram o valor prognóstico da monitorização ambulatorial da pressão arterial (MAPA em pacientes hipertensos resistentes, um grupo que apresenta alto risco. OBJETIVO: Investigar o valor prognóstico da pressão arterial (PA de vigília, em mulheres hipertensas resistentes. MÉTODOS: Foram acompanhadas por até 8,9 anos (média 3,9, 382 mulheres hipertensas resistentes com idade entre 24-92 anos, atendidas em uma unidade de hipertensão de um hospital universitário. As pacientes foram classificadas como controladas (PA de consultório > 140/90 mmHg e PA de vigília 140/90 mmHg e PA de vigília > 135/85 mmHg. Analisou-se uma combinação de mortalidade cardiovascular, cardiopatia isquêmica, acidente vascular encefálico e nefropatia. Utilizou-se o modelo proporcional de Cox para estimar o risco de eventos cardiovasculares ajustado para potenciais confundidores. RESULTADOS: A taxa total de eventos foi de 5,0 por 100 mulheres-ano. No grupo de controladas esse valor foi de 3,7 e entre as não-controladas, de 5,8, com p=0.06. Os riscos relativos associados ao aumento de 10 mmHg na PA sistólica, ajustando para idade e tabagismo atual, foram maiores que os associados a aumentos de 5 mmHg na PA diastólica. Pacientes com descenso noturno 10%, embora essa associação não tenha sido estatisticamente significante. A pressão de vigília não controlada (sim/não foi um forte fator de risco independente, 1,67 (1,00-2,78. CONCLUSÃO: O aumento de 67% no risco de evento cardiovascular quando a PA de vigília não estava controlada é indicador de que o uso da MAPA é essencial na avaliação do controle e como guia das decisões terapêuticas na hipertensão resistente.FUNDAMENTO: Pocos estudios exploraron el valor pronóstico del monitoreo ambulatorio de presión arterial (MAPA en pacientes hipertensos resistentes, un grupo que presenta alto riesgo. OBJETIVO: Investigar el valor pronóstico de la presión arterial (PA

  2. Impacto na reclassificação da hipertensão pela Monitorização Ambulatorial da Pressão Arterial (MAPA segundo a V Diretriz Brasileira de MAPA

    Directory of Open Access Journals (Sweden)

    Daniel Forestiero

    2013-02-01

    Full Text Available FUNDAMENTOS: Novas recomendações sobre valores de referência para normalidade em exames de monitorização ambulatorial da pressão arterial (MAPA foram propostas pela V Diretriz Brasileira de Monitorização Ambulatorial da Hipertensão Arterial, com base principalmente no estudo IDACO. OBJETIVOS: O presente estudo epidemiológico tem o objetivo de avaliar o impacto da adoção desses novos critérios em um ambulatório de referência em hipertensão arterial. MÉTODOS: Foram analisados resultados de 1.567 exames de MAPA realizados entre 2005 e 2010, excluídos 481 pacientes da amostra por não preencherem critérios mínimos de qualidade do exame. Para a classificação desses exames quanto à anormalidade, foram utilizados os valores de referência da IV Diretriz Brasileira de MAPA (2005 e comparados com as mudanças propostas na V Diretriz Brasileira de MAPA (2011. Foi realizada análise estatística pelo método do Q² de Pearson, considerando-se p significativo < 0,05. RESULTADOS: Para os 1.086 exames avaliados, houve importante diferença na proporção de pacientes com MAPA alterado, em especial para a variável pressão arterial sistólica do sono: 49% adotando os valores de corte de 2005 e 71% adotando os de 2011, com significância estatística, p < 0,0001. CONCLUSÕES: A recomendação da nova diretriz causou grande impacto na classificação da hipertensão pelos exames de MAPA dentro da população estudada. A questão sobre os limiares desses exames para metas terapêuticas de pacientes sabidamente hipertensos ainda está em aberto e carece de mais estudos, preferencialmente nacionais, para melhor definição do assunto.

  3. The effect of lower sodium concentration in dialysate on arterial stiffness in hemodialysis patients%低钠透析对血液透析患者大动脉僵硬度的影响

    Institute of Scientific and Technical Information of China (English)

    孙芳; 周亦伦; 刘婧; 马丽洁; 沈洋; 黄静; 崔太根; 刘淼冰

    2012-01-01

    for 4 months, without change of instructions about dietary sodium control. During the study period, dry weight was adjusted monthly with the help of bioimpedance spectroscope to maintain post-dialysis volume status in a steady state. PWV and 44-hour ambulatory blood pressure were measured. Results After the treatment for 4 months, PWV significantly decreased from 12.61 ± 2.30 to 11.74 ± 2.65 m/s (P=0.005). The 44-hour systolic and diastolic blood pressures were significantly lower than those at baseline (-10 mmHg and -6 mmHg, respectively), without change of post-dialysis volume parameters. Interdialytic weight gain decreased slightly from 2.89 ± 0.66 kg to 2.67 ± 0.63 kg (P=0.051). Conclusion Lower sodium concentration in dialysate improves arterial stiffness and blood pressure in HD patients.

  4. Modification over time of pulse wave velocity parallel to changes in aortic BP, as well as in 24-h ambulatory brachial BP.

    OpenAIRE

    Oliveras, Anna; Segura, Julián; Suárez, Carmen; García-Ortiz, Luis; Abad-Cardiel, María; Vigil, Luis; Gómez-Marcos, Manuel A.; Sans Atxer, Laia; Martell-Claros, Nieves; Ruilope, Luis Miguel; Sierra, Alejandro De la; RESCEN Study

    2016-01-01

    Arterial stiffness as assessed by carotid-femoral pulse wave velocity (cfPWV) is a marker of preclinical organ damage and a predictor of cardiovascular outcomes, independently of blood pressure (BP). However, limited evidence exists on the association between long-term variation (Δ) on aortic BP (aoBP) and ΔcfPWV. We aimed to evaluate the relationship of ΔBP with ΔcfPWV over time, as assessed by office and 24-h ambulatory peripheral BP, and aoBP. AoBP and cfPWV were evaluated in 209 hypertens...

  5. Black Raspberry Extract Increased Circulating Endothelial Progenitor Cells and Improved Arterial Stiffness in Patients with Metabolic Syndrome: A Randomized Controlled Trial.

    Science.gov (United States)

    Jeong, Han Saem; Kim, Sohyeon; Hong, Soon Jun; Choi, Seung Cheol; Choi, Ji-Hyun; Kim, Jong-Ho; Park, Chi-Yeon; Cho, Jae Young; Lee, Tae-Bum; Kwon, Ji-Wung; Joo, Hyung Joon; Park, Jae Hyoung; Yu, Cheol Woong; Lim, Do-Sun

    2016-04-01

    Administration of black raspberry (Rubus occidentalis) is known to improve vascular endothelial function in patients at a high risk for cardiovascular (CV) disease. We investigated short-term effects of black raspberry on circulating endothelial progenitor cells (EPCs) and arterial stiffness in patients with metabolic syndrome. Patients with metabolic syndrome (n = 51) were prospectively randomized into the black raspberry group (n = 26, 750 mg/day) and placebo group (n = 25) during the 12-week follow-up. Central blood pressure, augmentation index, and EPCs, such as CD34/KDR(+), CD34/CD117(+), and CD34/CD133(+), were measured at baseline and at 12-week follow-up. Radial augmentation indexes were significantly decreased in the black raspberry group compared to the placebo group (-5% ± 10% vs. 3% ± 14%, P raspberry group compared to the placebo group (19 ± 109/μL vs. -28 ± 57/μL, P raspberry group compared to the placebo group (-0.5 ± 1.4 pg/mL vs. -0.1 ± 1.1 pg/mL, P raspberry group. The use of black raspberry significantly lowered the augmentation index and increased circulating EPCs, thereby improving CV risks in patients with metabolic syndrome during the 12-week follow-up.

  6. Arterial stiffness, as monitored by cardio–ankle vascular index, is affected by obstructive sleep apnea, blood glucose control, and body weight – a case with 8 years follow up

    Directory of Open Access Journals (Sweden)

    Shimizu K

    2016-08-01

    Full Text Available Kazuhiro Shimizu,1 Tomoyuki Yamamoto,2,3 Kohji Shirai2,4 1Department of Internal Medicine, Toho University Sakura Medical Center, Chiba, Japan; 2Department of Vascular Function, Toho University Sakura Medical Center, Chiba, Japan; 3Biological Information Analysis Section, Fukuda Denshi Co., Ltd., Tokyo, Japan; 4Department of Internal Medicine, Mihama Hospital, Chiba, Japan Abstract: The cardio–ankle vascular index (CAVI is an indicator of arterial stiffness from the heart to the ankles. The CAVI increases as arteriosclerosis progresses, but it can be decreased by appropriate treatment. There are several risk factors for coronary artery disease, however, the degree of stress caused by each separate risk factor to arteries cannot be assessed. CAVI increases with age and according to the severity of atherosclerosis. We found that CAVI also changes in response to the control of risk factors, which may be associated with the functional stiffness of arteries. CAVI can be a useful indicator of risk control for coronary artery disease. We followed a patient aged 71 years who had diabetes mellitus and obstructive sleep apnea (OSA by measuring CAVI for 8 years from age 63. He underwent coronary artery bypass grafting due to angina pectoris when he was 63 years old. Before coronary artery bypass grafting, CAVI was 11.8 on the right and 11.5 on the left. Three years later he was found to have OSA and received treatment with continuous positive airway pressure. There was a marked improvement in CAVI after continuous positive airway pressure (age 68; right 10.4, left 10.2. However, following a gradual increase in body weight and worsening of diabetes mellitus, CAVI showed an increasing trend. CAVI decreased with biguanides treatment, but increased again with an increase in body weight. In conclusion, CAVI responded to the patient’s conditions including obesity, diabetes mellitus, and OSA. CAVI is not only a marker of arterial stiffness, but can also be a

  7. Associations of dietary intake patterns identified using reduced rank regression with markers of arterial stiffness among youth with type 1 diabetes

    Science.gov (United States)

    Lamichhane, Archana P.; Liese, Angela D.; Urbina, Elaine M.; Crandell, Jamie L.; Jaacks, Lindsay M.; Dabelea, Dana; Black, Mary Helen; Merchant, Anwar T.; Mayer-Davis, Elizabeth J.

    2014-01-01

    BACKGROUND/OBJECTIVES Youth with type 1 diabetes (T1DM) are at substantially increased risk for adverse vascular outcomes, but little is known about the influence of dietary behavior on cardiovascular disease (CVD) risk profile. We aimed to identify dietary intake patterns associated with CVD risk factors and evaluate their impact on arterial stiffness (AS) measures collected thereafter in a cohort of youth with T1DM. SUBJECTS/METHODS Baseline diet data from a food frequency questionnaire and CVD risk factors (triglycerides, LDL-cholesterol, systolic BP, HbA1c, C-reactive protein and waist circumference) were available for 1,153 youth aged ≥10 years with T1DM from the SEARCH for Diabetes in Youth Study. A dietary intake pattern was identified using 33 food-groups as predictors and six CVD risk factors as responses in reduced rank regression (RRR) analysis. Associations of this RRR-derived dietary pattern with AS measures [augmentation index(AIx75), n=229; pulse wave velocity(PWV), n=237; and brachial distensibility(BrachD), n=228] were then assessed using linear regression. RESULTS The RRR-derived pattern was characterized by high intakes of sugar-sweetened beverages (SSB) and diet soda, eggs, potatoes and high-fat meats, and low intakes of sweets/desserts and low-fat dairy; major contributors were SSB and diet soda. This pattern captured the largest variability in adverse CVD risk profile and was subsequently associated with AIx75 (β=0.47; p<0.01). The mean difference in AIx75 concentration between the highest and the lowest dietary pattern quartiles was 4.3% in fully adjusted model. CONCLUSIONS Intervention strategies to reduce consumption of unhealthful foods and beverages among youth with T1DM may significantly improve CVD risk profile and ultimately reduce the risk for AS. PMID:24865480

  8. Beneficial effects on arterial stiffness and pulse-wave reflection of combined enalapril and candesartan in chronic kidney disease--a randomized trial.

    Directory of Open Access Journals (Sweden)

    Marie Frimodt-Møller

    Full Text Available BACKGROUND: Cardiovascular disease (CVD is highly prevalent in patients with chronic kidney disease (CKD. Inhibition of the renin-angiotensinsystem (RAS in hypertension causes differential effects on central and brachial blood pressure (BP, which has been translated into improved outcome. The objective was to examine if a more complete inhibition of RAS by combining an angiotensin converting enzyme inhibitor (ACEI and an angiotensin receptor antagonist (ARB compared to monotherapy has an additive effect on central BP and pulse-wave velocity (PWV, which are known markers of CVD. METHODS: Sixty-seven CKD patients (mean GFR 30, range 13-59 ml/min/1.73 m(2 participated in an open randomized study of 16 weeks of monotherapy with either enalapril or candesartan followed by 8 weeks of dual blockade aiming at a total dose of 16 mg candesartan and 20 mg enalapril o.d. Pulse-wave measurements were performed at week 0, 8, 16 and 24 by the SphygmoCor device. RESULTS: Significant additive BP independent reductions were found after dual blockade in aortic PWV (-0.3 m/s, P<0.05 and in augmentation index (-2%, P<0.01 compared to monotherapy. Furthermore pulse pressure amplification was improved (P<0.05 and central systolic BP reduced (-6 mmHg, P<0.01. CONCLUSIONS: Dual blockade of the RAS resulted in an additive BP independent reduction in pulse-wave reflection and arterial stiffness compared to monotherapy in CKD patients. TRIAL REGISTRATION: Clinical trial.gov NCT00235287.

  9. 高血压患者动态脉压指数与冠状动脉病变的相关性分析%Correlation between ambulatory pulse pressure indexes and coronary artery lesions in patients with hypertension

    Institute of Scientific and Technical Information of China (English)

    冯玉平; 石慧荣; 赵立平

    2013-01-01

    Objective To investigate the correlation between ambulatory pulse pressure indexes (APPI) and coronary artery disease (CHD) in patients with hypertension. Methods The hypertensive patients (n=355) with coronary angiography (CAG) were chose from Apr. 2010 to Apr. 2013 and then divided into CHD group (n=237) and non-CHD group (n=118) according to CAG resutls. All patients were given 24-hour ambulatory blood pressure monitoring. The changes of SBP, DBP and pulse pressure (PP) were recorded and mean pressure [MBP=(SBP+DBP)/2] and PP index (PPI=PP/SBP) were calculated. The correlation between the above mentioned indexes and coronary artery lesions was analyzed. Results The levels of PP and APPI were higher in CHD group than those in non-CHD group [PP:(77.8±8.7) mmHg vs. (64.7±7.6) mmHg;APPI:(0.52±0.08) vs. (0.45±0.10) , P<0.05]. In CHD patients, the higher APPI value, the more severe coronary artery lesions (P<0.01). The results of Logistic analysis showed that APPI (OR=1.39), PP (OR=1.23) and SBP (OR=1.27) were risk factors of CHD (all P<0.01). Conclusion APPI value can be used for predict the severity of coronary artery lesions in patients with hypertension.%目的探讨高血压患者动态脉压指数(pluse pressure index,PPI)与冠状动脉病变的相关性。方法纳入2010年4月~2013年4月实施冠状动脉造影(CAG)的高血压患者355例。根据CAG结果将患者分为冠心病组(n=237)及非冠心病组(n=118)。对所有研究对象均进行24 h动态血压监测,记录收缩压(SBP)、舒张压(DBP)和脉压(PP),计算脉压指数(PPI,PPI=PP/SBP)。分析上述因素与冠状动脉病变的相关性。结果与非冠心病组相比,冠心病组患者PP及PPI水平更高,分别为(77.8±8.7)mmHg vs.(64.7±7.6)mmHg,(0.52±0.08) vs.(0.45±0.10),差异有统计学意义(P<0.05)。在冠心病患者中,PPI值越高,患者冠脉病变数值越高(P<0.01

  10. 超重和肥胖与动脉僵硬度的相关性研究%Association between overweight, obesity and arterial stiffness in community residents

    Institute of Scientific and Technical Information of China (English)

    黄晖明; 李森; 许浩

    2011-01-01

    Objective To evaluate the relationship between overweight,obesity and arterial stiffness in community residents.Methods A total of 4585 community-dwelling adults in Jiangsu province,China were surveyed with the method of stratified and cluster sampling from 2007 to 2009.Overweight and obesity were defined by body mass index (BMI) and arterial stiffness was assessed by brachial-ankle pulse wave velocity (baPWV).Statistical analysis of arteriosclerosis included multivariate logistic regression testing among which BMI was viewed as continuous variable( 1 kg/m2 increasing to BMI)and categorical variables (underweight,normal,overweight and obesity) respectively.Odds ratio,population attributable risk percent and the optimal cut-off points for BMI to evaluate arteriosclerosis were analyzed using receiver operator characteristic (ROC) curve.Results ( 1 ) After age control,BMI of male or female were positively correlated with baPWV (r =0.213,P <0.01; r =0.186,P <0.01).baPWV and prevalence of arteriosclerosis were significantly higher in obese residents compared with normal body weight group ( all P < 0.01 ).(2)As a continuous variable,the odds ratio value of BMI on predicting arteriosclerosis was 1.146 (95%CI:1.117 - 1.175,P < 0.01 ) after adjusting of age,gender and hypertension.As categorical variables,the odds ratio value of BMI was 0.369(95% CI:0.141 -0.962,P <0.05) for underweight group,1.576 (95% CI:1.333 - 1.863 ) for overweight group and 2.087 ( 95% CI:1.615 - 2.698 ) for obesity group (all P <0.01 ).(3) The population attributable arteriosclerosis risk was 19.1% and 11.6%in overweight and obesity groups,respectively.The area under the ROC curve was 0.661 (95% CI:0.645 -0.678,P < 0.01 ) and the optimal cut-off point for BMI to evaluate arteriosclerosis was 24.25 kg/m2.Conclusions Overweight and obese residents faced higher risk for arteriosclerosis than normal population.Overweight and obesity are independent risk factors for

  11. Ambulatory Surgical Measures - National

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Ambulatory Surgical Center Quality Reporting (ASCQR) Program seeks to make care safer and more efficient through quality reporting. ASCs eligible for this...

  12. Ambulatory Surgical Measures - Facility

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Ambulatory Surgical Center Quality Reporting (ASCQR) Program seeks to make care safer and more efficient through quality reporting. ASCs eligible for this...

  13. Estimation of blood pressure variability from 24-hour ambulatory finger blood pressure

    NARCIS (Netherlands)

    Omboni, S.; Parati, G.; Castiglioni, P.; Rienzo, M. di; Imholz, B.P.M.; Langewouters, G.J.; Wesseling, K.H.; Mancia, G.

    1998-01-01

    Portapres is a noninvasive, beat-to-beat finger blood pressure (BP) monitor that has been shown to accurately estimate 24-hour intra-arterial BP at normal and high BPs. However, no information is available on the ability of this device to accurately track ambulatory BP variability. In 20 ambulatory

  14. Arterial Stiffness by Aerobic Exercise Is Related with Aerobic Capacity, Physical Activity Energy Expenditure and Total Fat but not with Insulin Sensitivity in Obese Female Patients with Type 2 Diabetes

    Directory of Open Access Journals (Sweden)

    Ji Yeon Jung

    2014-12-01

    Full Text Available BackgroundArterial stiffness is an important factor in atherosclerosis. Thus we examined whether aerobic exercise could reduce arterial stiffness in obese women with type 2 diabetes without diabetic complication.MethodsA total of 35 women with type 2 diabetes (body mass index, 26.6±2.8 kg/m2; age, 56.4±1.9 years; duration of diabetes, 4.7±4.8 years were assigned to aerobic exercise group (AEG or control group (CG. AEG completed a 12-week exercise program (3.6 to 5.2 metabolic equivalents, 3 day/week, 60 min/day, with their exercise activities monitored by accelerometers. We measured abdominal total fat area (TFA, visceral fat area (VFA, and subcutaneous fat area (SFA by computed tomography, insulin sensitivity by insulin tolerance test (KITT, and augmentation index (AIx by SphygmoCor at baseline and at the end of the 12-week program.ResultsThe AIx was improved in the AEG compared with the CG (P<0.001. The percent change of AIx had significant correlation with the improvement of physical activity energy expenditure (PAEE, aerobic capacity, TFA, and SFA (r=-0.416, P=0.013; r=0.560, P<0.001; r=0.489, P=0.003; r=0.531, P=0.001, respectively, but not with insulin sensitivity, energy intake, or VFA.ConclusionImprovement in aortic stiffness by aerobic exercise is related with the improvement of aerobic capacity, PAEE, and total fat but not with insulin sensitivity or energy intake in obese women with type 2 diabetes.

  15. Stiff railguns

    Science.gov (United States)

    Weldon, W. F.; Bacon, J. L.; Weeks, D. A.; Zowarka, R. C., Jr.

    1991-01-01

    Stiff guns have been operated with both plasma and solid armatures. A performance gain was seen in the plasma railgun as stiffness was increased. A stiff gun will help to maintain the bore shape and preserve the integrity of the seam between rail and insulator under the extreme asymmetric loads sustained during high-pressure operation. The hydraulically preloaded moly and ceramic gun has been fired six times at pressures as high as 87 ksi, and the bore still holds roughing vacuum up to two hours after the test. The elimination of seam leakage helps control bore erosion associated with plasma reconstitution from the rail and plasma perturbation that might result in loss-initiating instabilities. Reduced rail deflection allows solid and transitioning armatures to track the bore surface. An analysis of the strain energy associated with the deflection of the railgun structure is presented, and this mechanism is found to be a small fraction of the energy associated with armature loss and the rail resistive loss.

  16. Numerical assessment of the stiffness index.

    Science.gov (United States)

    Epstein, Sally; Vergnaud, Anne-Claire; Elliott, Paul; Chowienczyk, Phil; Alastruey, Jordi

    2014-01-01

    Elevated systemic vascular stiffness is associated with increased risk of cardiovascular disease. It has been suggested that the time difference between the two characteristic peaks of the digital volume pulse (DVP) measured at the finger using photoplethysmography is related to the stiffness of the arterial tree, and inversely proportional to the stiffness index (SI). However, the precise physical meaning of the SI and its relation to aortic pulse wave velocity (aPWV) is yet to be ascertained. In this study we investigated numerically the effect of changes in arterial wall stiffness, peripheral resistances, peripheral compliances or peripheral wave reflections on the SI and aPWV. The SI was calculated from the digital area waveform simulated using a nonlinear one-dimensional model of pulse wave propagation in a 75-artery network, which includes the larger arteries of the hand. Our results show that aPWV is affected by changes in aortic stiffness, but the SI is primarily affected by changes in the stiffness of all conduit vessels. Thus, the SI is not a direct substitute for aPWV. Moreover, our results suggest that peripheral reflections in the upper body delay the time of arrival of the first peak in the DVP. The second peak is predominantly caused by the impedance mismatch within the 75 arterial segments, rather than by peripheral reflections.

  17. The effect of new-onset diabetes after renal transplantation on arterial stiffness%肾移植术后新发糖尿病的危险因素及其对动脉僵硬度的影响

    Institute of Scientific and Technical Information of China (English)

    刘航; 史屹; 沈中阳

    2009-01-01

    目的 探讨肾移植术后新发糖尿病(NODAT)的影响因素以及动脉僵硬度与移植术后新发糖尿病之间的相关性.方法 195例肾移植患者,根据糖耐量检查的结果分为NODAT与非NODAT两组.应用动脉硬化检测仪检测患者的肱一踝脉搏波传导速度(baPWV)、踝肘血压指数(ABPI)以及颈动脉内膜中层厚度(IMT),同时对入选对象进行血清学检测,根据动脉僵硬度指标分析两组之间的差异.结果 29例移植术后诊断为NODAT,与非NODAT患者相比,移植术前的空腹血糖(FPG)、血压以及丙型肝炎病毒(HCV)感染率都处于一个相当高的水平.多变量回归分析提示,术前HCV感染率、FPG水平以及收缩压是关系到NODAT发生的危险因素.NODAT患者的baPWV明显快于非NODAT患者,同时高血压、年龄以及术后糖化血红蛋白是动脉僵硬度进展的独立决定性因素.结论 肾移植术前高水平的FPG、HCV感染以及持续的高血压状态是引起NODAT的危险因素;高血压、年龄偏大以及糖化血红蛋白升高对动脉僵硬度的进展具有重要影响.%Objective To investigate the risk factor for new-onset diabetes after transplantation (NODAT) and the relationship between NODAT and arterial stiffness. Methods Oral glucose tolerance test (OGTT) was performed on 195 patients with renal transplantation. The degree of arterial stiffness, which was determined by brachial ankle pulse wave velocity (baPWV), anklebrachial blood pressure index (ABPI) and intima-media thickness (IMT) of the carotid artery, was evaluated. Results Twenty-nine patients diagnosed as NODAT had significantly higher fasting plasma glucose before transplantation, blood pressure and incidence of hepatitis C virus (HCV) infection than in patients without NODAT. Multivariate regression analysis revealed that the risk factor of NODAT was fasting plasma glucose pre-transplantation, HCV infection and systolic blood pressure.The independent determinant of the

  18. Relationship between serum albumin and pulse wave velocity in patients on continuous ambulatory peritoneal dialysis

    Directory of Open Access Journals (Sweden)

    Li-Tao Cheng

    2008-08-01

    Full Text Available Li-Tao Cheng1, Li-Jun Tang1,2, Hui-Min Chen1,3, Wen Tang1, Tao Wang11Division of Nephrology, Peking University Third Hospital, Beijing, China; 2Division of Nephrology, Qilu Hospital of Shandong University, Ji’nan, China; 3Division of Cardiology, Guangdong Provincial Hospital of Traditional Chinese Medicine, Guangzhou, ChinaBackground: Hypoalbuminemia is a risk factor for cardiovascular events and mortality in dialysis patients, but the underlying mechanism remains unclear. Meanwhile, increased pulse wave velocity (PWV, the marker of arterial stiffness, has been proved to be an independent predictor of cardiovascular disease. The relationship between serum albumin and PWV in continuous ambulatory peritoneal dialysis patients (CAPD was studied.Methods: Sixty-two CAPD patients were studied. The average age was 63 ± 12 years and dialysis duration was 23 ± 22 months. Serum albumin, C-reactive protein (CRP, and carotid-femoral PWV were measured.Results: Among these patients, 43.5% were men. The mean serum albumin concentration was 37 ± 4 g/L and PWV was 11.9 ± 2.3 m/s. PWV positively correlated with age (r = 0.35, P < 0.01, diabetes (yes = 1, no = 0; r = 0.292, P < 0.05, systolic blood pressure (SBP; r = 0.493, P < 0.001 and CRP (r = 0.295, P < 0.05, but negatively correlated with serum albumin (r = −0.357, P < 0.01. In multiple regression analysis, SBP (β = 0.615, P < 0.001, age (β = 0.414, P < 0.01, albumin (β = −0.315, P < 0.05 and total cholesterol (β = 0.275, P < 0.05 were independent determinants of PWV. In a non-inflamed subgroup (CRP < 3 mg/L, n = 30, albumin still negatively correlated with PWV (r = −0.66, P < 0.001.Conclusion: Serum albumin inversely correlated with increased PWV in CAPD patients, suggesting that increased arterial stiffness might be the link between hypoalbuminemia and increased cardiovascular mortality in dialysis patients.Keywords: hypoalbuminemia, cardiovascular events, pulse wave velocity, arterial

  19. Age, hypertension and arterial function.

    Science.gov (United States)

    McEniery, Carmel M; Wilkinson, Ian B; Avolio, Albert P

    2007-07-01

    1. Ageing exerts a marked effect on the cardiovascular system and, in particular, the large arteries. Using a variety of techniques to assess arterial stiffness, many cross-sectional studies have demonstrated a significant relationship between age and aortic stiffness, although the age-related changes observed in peripheral arteries appear to be less marked. 2. The relationship between arterial stiffness and hypertension is more complex. The distending, or mean arterial, pressure is an important confounder of measurements of arterial stiffness and, therefore, must be taken into consideration when assessing arterial stiffness in hypertensive subjects or investigating the effect of antihypertensive agents. Current methods for correcting for differences in distending pressure involve pharmacological manipulation, statistical correction or mathematical manipulation of stiffness indices. 3. Many studies have provided evidence that both peripheral (muscular) and central (elastic) arteries are stiffer in subjects with mixed (systolic/diastolic) hypertension compared with normotensive subjects. However, it is unclear to what extent differences in mean arterial pressure explain the observed differences in hypertensive subjects. In contrast, isolated systolic hypertension is associated with increased aortic, but not peripheral artery, stiffness, although the underlying mechanisms are somewhat unclear. 4. Traditional antihypertensive agents appear to reduce arterial stiffness, but mostly via an indirect effect of lowering mean pressure. Therefore, therapies that target the large arteries to reduce stiffness directly are urgently required. Agents such as nitric oxide donors and phosphodiesterase inhibitors may be useful in reducing stiffness via functional mechanisms. In addition, inhibitors or breakers of advanced glycation end-product cross-links between proteins, such as collagen and elastin, hold substantial promise.

  20. Prevalence of peripheral vascular disease and its association with carotid intima-media thickness and arterial stiffness in type 2 diabetes: the Chennai urban rural epidemiology study (CURES 111).

    Science.gov (United States)

    Pradeepa, Rajendra; Chella, Sundarapandi; Surendar, Jayagopi; Indulekha, Karunakaran; Anjana, Ranjit Mohan; Mohan, Viswanathan

    2014-05-01

    We investigated the prevalence of peripheral vascular disease (PVD) and its association with preclinical atherosclerotic markers [intima-media thickness (IMT)] and arterial stiffness among 1755 urban south Indian type 2 diabetic subjects recruited from the Chennai Urban Rural Epidemiology Study (CURES). Doppler studies were performed, and PVD was defined as ankle-brachial index (ABI) of ≤0.9. IMT of the common carotid artery was determined using high-resolution B-mode ultrasonography, and augmentation index (AGI) was measured using the Sphygmocor apparatus. The overall prevalence of PVD was 8.3% (age-standardized 6.5%). The prevalence of PVD was higher among known diabetic subjects (n = 1401) compared to newly detected diabetic subjects (n = 354) (8.6% vs 6.8%, p = 0.250). The mean IMT and AGI in subjects with PVD were significantly higher compared to subjects without PVD (IMT: 0.99 ± 0.26 mm vs 0.83 ± 0.19 mm; AGI: 28.1 ± 9.6% vs 25.7 ± 9.8%, respectively). IMT was independently associated with PVD even after adjusting for age [odds ratio (OR) = 2.9 (1.2-6.7), p = 0.016 for second tertile and OR = 3.9 (1.7-9.3), p = 0.002 for third tertile compared to first tertile]. AGI was also associated with PVD in the unadjusted model [OR = 1.8 (1.1-3.1), p = 0.027 for second tertile compared to first tertile]. However, when adjusted for age, the significance was lost. In conclusion, among urban south Indian type 2 diabetic subjects, the prevalence of PVD is 8.3% and IMT is more strongly associated with PVD than AGI.

  1. 中心动脉脉压是影响大动脉僵硬度的主要因素%Central pulse pressure but not brachial blood pressure is the predominant factor affecting aortic arterial stiffness

    Institute of Scientific and Technical Information of China (English)

    肖文凯; 叶平; 白永怿; 骆雷鸣; 吴红梅; 高鹏

    2015-01-01

    目的:观察高血压患者及血压正常人群中心动脉血流动力学差异;探讨哪种血压指标与动脉僵硬度及血管损害标志物更密切相关。方法从北京地区社区人群中筛选出820名高血压患者,同时入选820名与之年龄、性别相匹配的血压正常者。采用脉搏波传播速度(PWV)自动测量系统测定颈-股动脉PWV和颈-桡动脉PWV;应用张力测量法测量中心动脉压和中心动脉脉搏波增强指数(AIx)。同时血浆同型半胱氨酸(HCY),高敏C反应蛋白(HsCRP)及N末端脑利钠肽前体(NT-proBNP)被测定。结果无论是高血压患者还是血压正常人群,中心动脉收缩压和脉压显著低于相应的肱动脉收缩压和脉压,这种脉压扩增在血压正常组9.85±6.55 mmHg明显低于高血压组12.64±6.69 mmHg,但在脉压扩增比上两组未见差异。大动脉僵硬度受血压及年龄的影响,高血压组具有较高的颈股动脉PWV和中心动脉AIx,脉压扩增比随年龄的增长而递减。单因素分析见中心脉压相对其它血压指标与动脉僵硬度和血管损害标志物的相关性更强;多元逐步回归分析显示颈股动脉PWV和中心动脉AIx受中心脉压的独立影响而外周平均动脉压及脉压未进入回归方程。结论中心动脉脉压相对其它血压指标可能是中心动脉僵硬度更直接的指示器和更好的血管老化的标志,未来的临床试验中可能更多地将中心动脉压作为治疗的靶目标值。%Objective To investigate the differences in central hemodynamic indices between hypertensive and normotensive subjects and identify the blood pressure index that the most strongly correlate with arterial stiffness and vascular damage markers. Methods A cohort of 820 hypertensive patients and 820 normotensive individuals matched for age and gender were enrolled in this study. We measured carotid-femoral and carotid-radial pulse wave velocity (PWV), aortic

  2. Zusammenhang zwischen maximaler Sauerstoffaufnahme und arterieller Gefäßsteifigkeit in Ruhe und während eines Cold Pressure Tests // Relationship between Maximal Oxygen Consumption and Arterial Stiffness at Rest and during Cold Pressor Stress Testing

    Directory of Open Access Journals (Sweden)

    Milatz F

    2016-01-01

    Full Text Available iIntroduction:/i The favorable influence of endurance exercise on arterial stiffness (AS is widely known. It is also well accepted that stress contributes the development of arterial stiffness and predict the risk of cardiovascular events. The aim of this study was to investigate the relationship between maximal oxygen consumption (VO2max and arterial stiffness (AS, quantified by aortic pulse wave velocity (aPWV and augmentation index (AIx, at rest, but in par- ticular during stress testing.br iMethods:/i 32 recreationally active men completed a cardiopulmonary exercise testing. aPWV and AIx were measured non-invasively at rest and during a 2 minute cold pressor test (CPT using Mobil-O-Graph®. After applying partial correlation analysis, the cohort was divided into tertiles of VO2max. Thereafter, ANCOVAs adjusted for age, body mass index and height were performed. br iResults:/i In the total cohort VO2max showed negative correlations with AIx (r = –0.49, p = 0.006 at rest and with AIx (r = –0.51, p = 0.005 as well as aPWV (r = –0.55, r = 0.001 stress test-related. Subjects in the highest tertile of VO2max showed significantly lower stiffness parameters than subjects in the lowest tertile. This was true for AIx (1.1% vs 10.2%, p = 0.012 at rest and for AIx (3.3% vs 13.9%, p = 0.015 as well as aPWV (6.0 m/s vs 6.9 m/s, p = 0.006 during CPT, respectively.br iDiscussion:/i The study provides evidence for an inverse relationship between VO2max and stress test-related AS. Furthermore higher VO2max values seem to be associated with more favorable effects on arterial compliance during stress testing irrespective of known factors influencing AS. p bKurzfassung: /biEinleitung:/i Ausdauertraining besitzt bekanntermaßen günstige Effekte auf die arterielle Gefäßsteifigkeit (AS. Evidenzen aus der kardiovaskulären Forschung sprechen jedoch dafür, dass das kardiovaskuläre Risiko insbesondere durch die Gefäßcompliance während körperlicher und

  3. Correlation between arterial stiffness and left ventricular function in patients with primary hypertension%原发性高血压患者动脉僵硬度与心脏重构的相关性研究

    Institute of Scientific and Technical Information of China (English)

    曾锋; 汤达鹏; 余钷; 罗柳玲; 刘建芬; 梁国华

    2013-01-01

    目的 探讨原发性高血压患者动脉僵硬度与左心功能的相关性.方法 纳入原发性高血压患者79例,根据颈桡脉搏波传导速度(PWV)将患者分为对照组(PWV<0.9m/s,n=42)和观察组(PWV≥0.9m/s,n=37),两组患者均行心脏彩超检查比较心功能参数差异.结果 两组患者间左室舒张末期内径(LVEDd)、左室射血分数(LVEF)、左室质量指数(LVMI)、二尖瓣舒张早期血流峰速(E)、舒张晚期血流峰速(A)及二者比值(E/A)差异具有统计学意义(P<0.05);Pearson相关分析显示PWV与LVMI存在显著的相关性(r=0.347,P<0.05).结论 原发性高血压患者动脉僵硬度与左心重构存在显著的相关性,在临床上检测动脉弹性对于评价高血压患者心脏重构具有显著的临床意义.%Objective To discuss the correlation between arterial stiffness and left ventricular function in patients with primary hypertension. Methods The patients ( n=79 ) were divided, according to carotid-radial pulse wave velocity ( PWV ) , into control group ( PWV<0.9 m/s, n=42 ) and observation group ( PWV ≥ 0.9 m/s, n=37 ) . All patients were given the examination of color Doppler echocardiography, and the difference in cardiac function parameters were compared between two groups. Results The difference in cardiac function parameters, including left ventricular end-diastolic inner diameter ( LVEDd ) , left ventricular ejection fraction ( LVEF ) , left ventricular mass index ( LVMI ) , mitral early diastole inflow velocity ( E ) , late diastole inflow velocity ( A ) and ratio of E to A ( E/A ) , had statistical significance between two groups ( P<0.05 ) . Pearson correlation analysis showed that there was a significant correlation between PWV and LVMI ( r=0.347, P<0.05 ) . Conclusion The arterial stiffness is significantly correlated to left ventricular function, and examination of arterial elasticity is significant for reviewing ventricular remodeling in in patients with primary

  4. Management of comorbidities in ambulatory anesthesia: a review

    Directory of Open Access Journals (Sweden)

    Dabu-Bondoc S

    2015-06-01

    Full Text Available Susan Dabu-Bondoc, Kirk Shelley Department of Anesthesiology, School of Medicine, Yale University, New Haven, CT, USAAbstract: Advances in medical science now allow people with significant medical issues to live at home. As the outpatient population ages and surgical techniques advance, the ambulatory anesthesiologist has to be prepared to handle these “walking wounded”. The days of restricting ambulatory surgery procedures to American Society of Anesthesiologists class 1 and 2 patients are rapidly fading into the past. To remain competitive and economically viable, the modern ambulatory surgery center needs to expand its practice to include patients with medical comorbidities. In an environment where production and economic pressures exist, maintaining safety and good outcomes in high-risk patients for ambulatory surgery can be arduous. Adding to the complexity of this challenge is the rapid evolution of the therapeutic approaches to a variety of medical issues. For example, there has been a significant increase in the number and types of insulin a diabetic patient might be prescribed in recent years. In the case of the patient with coronary artery disease, the variety of both drug and nondrug eluding stents or new antithrombotic agents has also increased the complexity of perioperative management. Complex patients need careful, timely, and team-based preoperative evaluation by an anesthesia provider who is knowledgeable of outpatient care. Optimizing comorbidities preoperatively is a crucial initial step in minimizing risk. This paper will examine a number of common medical issues and explore their impact on managing outpatient surgical procedures.Keywords: ambulatory surgery, medical comorbidities, diabetes, coronary artery disease, respiratory disease, obesity

  5. 新疆维吾尔族健康及冠心病人群中体质指数、腰围与动脉僵硬程度相关性研究%Correlation between the body mass index, the waist circumference and the arterial stiffness in ;healthy and coronary artery disease Uygur population of the Xinjiang

    Institute of Scientific and Technical Information of China (English)

    刘军; 潘硕; 马依彤; 陈铀; 陶静

    2014-01-01

    Objective To study the correlation between the body mass index, the waist circumference and the arterial stiffness in healthy and coronary artery disease Uygur population in Xinjiang. Methods The study included 113 coronary artery disease patients and 92 healthy people in the Xinjiang. Their body mass index, waist circumference, and brachial-ankle pulse wave index and biochemical value were measured. In the healthy people and the coronary artery disease patients, the linear correlation analysis is performed with the body mass index, the waist circumference and brachial-ankle pulse wave index. The confounding factors of the brachial-ankle pulse wave index were adjusted. Results In healthy people, the pulse wave index (PWV) was not correlated with body mass index (BMI)(r=0.076, P>0.05). The PWV was positively correlated with waist circumference(r=0.218, P<0.05). In coronary artery disease patients, the PWV was positively correlated with BMI(r=0.232, P<0.01).The PWV was positively correlated with waist circumference(r=0.256, P<0.01). After adjusting for age, gender, and other cardiovascular risk factors, each additional 1 kg/m2 in BMI may be accompanied with an increase of 0.053 m/s in the PWV, each 1 cm increase in waist circumference may be accompanied with an increase of 0.027 m/s in the PWV. Conclusion Whether in the healthy or coronary artery disease Uygur population, the measure of abdominal obesity (waist circumference) and general obesity (BMI) were positively associated with arterial stiffness presented by the PWV.%目的:研究新疆地区维吾尔族健康及冠心病人群中体质指数(BMI)、腰围与动脉僵硬程度相关性。方法本研究纳入新疆地区冠心病患者113例,健康人92人。测量其体质指数、腰围、臂踝脉搏波传导速度(PWV)及各项生化指标。分别在健康人群与冠心病人群中,用体质指数、腰围与PWV做线性相关性分析,并对PWV的影响因素进行校正。结果在健

  6. 老年维持性血液透析患者透析间期血压节律的影响因素分析%Investigation of factors of circadian rhythm of interdialytic ambulatory blood pressure in elderly maintenance hemodialysis patients

    Institute of Scientific and Technical Information of China (English)

    王莹; 牛建英; 范伟锋; 罗丽红; 钱英俊; 张绮; 顾勇

    2011-01-01

    mean parathyroid hormone level, ambulatory arterial stiffness index, symmetrical ambulatory arterial stiffness index, left ventricular mass index in the abnormal blood pressure rhythm group were obviously higher than those in the normal group and these differences were statistically significant (P < 0.05). (2) Multivariate Logistic regression proportional analyses showed that parathyroid hormone, symmetrical ambulatory arterial stiffness index, left ventricular hypertrophy were the independent risk factors of circadian rhythm of interdialytic ambulatory blood pressure in the elderly MHD patients. Conclusion Secondary hyperparathyroidism, arterial sclerosis and left ventricular hypertrophy were the independent risk factors influencing nocturnal systolic blood pressure fall and blood pressure rhythm in elderly maintenance hemodialy sis patients.

  7. Estimating Gear Teeth Stiffness

    DEFF Research Database (Denmark)

    Pedersen, Niels Leergaard

    2013-01-01

    The estimation of gear stiffness is important for determining the load distribution between the gear teeth when two sets of teeth are in contact. Two factors have a major influence on the stiffness; firstly the boundary condition through the gear rim size included in the stiffness calculation...

  8. Stiff person syndrome.

    Science.gov (United States)

    Ciccoto, Giuseppe; Blaya, Maike; Kelley, Roger E

    2013-02-01

    Recognizing stiff person syndrome is clinically important. It is uncommon, characterized by body stiffness associated with painful muscle spasms, and varies in location and severity. It is subdivided into stiff trunk versus stiff limb presentation, and as a progressive encephalomyelitis. Stiff person-type syndrome also reflects a paraneoplastic picture. Most patients demonstrate exaggerated lumbar lordosis. Roughly 60% of patients have antiglutamic acid decarboxylase antibodies in the blood and the cerebrospinal fluid. The differential diagnosis includes many severe conditions. There are reports of response to muscle relaxants, immunosuppressants, intravenous gamma globulin, plasma exchange, a number of anticonvulsants, and botulinum toxin.

  9. Correlation of vitamin D deficiency and arterial stiffness in patients with chronic kidney disease%慢性肾脏病患者维生素D缺乏与动脉僵硬度的相关性

    Institute of Scientific and Technical Information of China (English)

    王来亮; 高燕红; 罗群

    2015-01-01

    目的 探讨慢性肾脏病患者维生素D缺乏与动脉僵硬度的相关性.方法 选取慢性肾脏病(CKD l~5期)患者300例,根据血25(OH)D3浓度分为维生素D缺乏组[25 (OH)D3<20 μg/L]和维生素D非缺乏组[25(OH)D3≥20 μg/L].采集临床资料数据,测定动脉僵硬度指标肱踝脉搏波传导速度(baPWV).对血25(OH)D3水平与baPWV间的关系进行单因素相关分析及多元线性回归分析. 结果 维生素D缺乏组188例(62.7%),维生素D非缺乏组112例(37.3%).全部CKD患者25(OH)D3平均浓度为(17.62±8.54) μg/L,维生素D缺乏组和非缺乏组分别为(12.38±4.55) μg/L与(26.44±6.05) μg/L(P<0.01).维生素D缺乏组baPWV值高于非缺乏组[(1 827.34±429.11) cm/s比(1 555.31±353.14) cm/s,P<0.01].单因素相关分析显示全体CKD患者(r=-0.38,P<0.01)以及CKD 2~5期患者[r=-0.30,P<0.05;r=-0.26,P<0.05;r=-0.46,P<0.01;r=-0.57,P<0.01]血25(OH)D3浓度与baPWV均呈负相关.多元线性回归分析显示血25 (OH)D3浓度下降与baPWV的增加独立相关(模型1:β=-0.18,P<0.01;模型2:β=-0.17,P=0.01),回归模型1与模型2均可解释baPWV变化的50%.结论 CKD患者普遍存在维生素D缺乏,维生素D缺乏与动脉僵硬度增加相关.维生素D替代治疗可能影响CKD患者的心血管预后,但有待未来研究的进一步明确.%Objective To evaluate the association between serum 25-hydroxyvitamin D3 [25 (OH)D3] and arterial stiffness in patients with chronic kidney disease (CKD).Methods Three hundred patients with CKD were included,and were divided into two groups based on serum 25(OH)D3 levels:vitamin D deficient [25(OH)D3 < 20 μg/L] and vitamin D non-deficient [25(OH)D3≥20 μg/L].Brachial ankle pulse wave velocity (baPWV),which reflected arterial stiffness,was calculated using the single-point method.Clinical data were collected in details.Correlation between serum 25(OH)D3 level and baPWV was assessed by the single factor correlation test and multiple

  10. Simvastatin Ameliorates Matrix Stiffness-Mediated Endothelial Monolayer Disruption.

    Directory of Open Access Journals (Sweden)

    Marsha C Lampi

    Full Text Available Arterial stiffening accompanies both aging and atherosclerosis, and age-related stiffening of the arterial intima increases RhoA activity and cell contractility contributing to increased endothelium permeability. Notably, statins are 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA reductase inhibitors whose pleiotropic effects include disrupting small GTPase activity; therefore, we hypothesized the statin simvastatin could be used to attenuate RhoA activity and inhibit the deleterious effects of increased age-related matrix stiffness on endothelial barrier function. Using polyacrylamide gels with stiffnesses of 2.5, 5, and 10 kPa to mimic the physiological stiffness of young and aged arteries, endothelial cells were grown to confluence and treated with simvastatin. Our data indicate that RhoA and phosphorylated myosin light chain activity increase with matrix stiffness but are attenuated when treated with the statin. Increases in cell contractility, cell-cell junction size, and indirect measurements of intercellular tension that increase with matrix stiffness, and are correlated with matrix stiffness-dependent increases in monolayer permeability, also decrease with statin treatment. Furthermore, we report that simvastatin increases activated Rac1 levels that contribute to endothelial barrier enhancing cytoskeletal reorganization. Simvastatin, which is prescribed clinically due to its ability to lower cholesterol, alters the endothelial cell response to increased matrix stiffness to restore endothelial monolayer barrier function, and therefore, presents a possible therapeutic intervention to prevent atherogenesis initiated by age-related arterial stiffening.

  11. Simvastatin Ameliorates Matrix Stiffness-Mediated Endothelial Monolayer Disruption.

    Science.gov (United States)

    Lampi, Marsha C; Faber, Courtney J; Huynh, John; Bordeleau, Francois; Zanotelli, Matthew R; Reinhart-King, Cynthia A

    2016-01-01

    Arterial stiffening accompanies both aging and atherosclerosis, and age-related stiffening of the arterial intima increases RhoA activity and cell contractility contributing to increased endothelium permeability. Notably, statins are 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors whose pleiotropic effects include disrupting small GTPase activity; therefore, we hypothesized the statin simvastatin could be used to attenuate RhoA activity and inhibit the deleterious effects of increased age-related matrix stiffness on endothelial barrier function. Using polyacrylamide gels with stiffnesses of 2.5, 5, and 10 kPa to mimic the physiological stiffness of young and aged arteries, endothelial cells were grown to confluence and treated with simvastatin. Our data indicate that RhoA and phosphorylated myosin light chain activity increase with matrix stiffness but are attenuated when treated with the statin. Increases in cell contractility, cell-cell junction size, and indirect measurements of intercellular tension that increase with matrix stiffness, and are correlated with matrix stiffness-dependent increases in monolayer permeability, also decrease with statin treatment. Furthermore, we report that simvastatin increases activated Rac1 levels that contribute to endothelial barrier enhancing cytoskeletal reorganization. Simvastatin, which is prescribed clinically due to its ability to lower cholesterol, alters the endothelial cell response to increased matrix stiffness to restore endothelial monolayer barrier function, and therefore, presents a possible therapeutic intervention to prevent atherogenesis initiated by age-related arterial stiffening.

  12. A relation between blood pressure and stiffness of joints and skin

    NARCIS (Netherlands)

    Uiterwaal, CSPM; Grobbee, DE; Sakkers, RJB; Helders, PJM; Bank, RA; Engelbert, RHH

    2003-01-01

    Background. Blood pressure, particularly pulse pressure, is associated with arterial wall stiffness, but little is known about its relation to stiffness of other parts of the body. We examined the extent to which blood pressure levels in young healthy children are related to stiffness of various tis

  13. Personal black carbon exposure influences ambulatory blood pressure: air pollution and cardiometabolic disease (AIRCMD-China) study.

    Science.gov (United States)

    Zhao, Xiaoyi; Sun, Zhichao; Ruan, Yanping; Yan, Jianhua; Mukherjee, Bhramar; Yang, Fumo; Duan, Fengkui; Sun, Lixian; Liang, Ruijuan; Lian, Hui; Zhang, Shuyang; Fang, Quan; Gu, Dongfeng; Brook, Jeffrey R; Sun, Qinghua; Brook, Robert D; Rajagopalan, Sanjay; Fan, Zhongjie

    2014-04-01

    Few prospective studies have assessed the blood pressure effect of extremely high air pollution encountered in Asia's megacities. The objective of this study was to evaluate the association between combustion-related air pollution with ambulatory blood pressure and autonomic function. During February to July 2012, personal black carbon was determined for 5 consecutive days using microaethalometers in patients with metabolic syndrome in Beijing, China. Simultaneous ambient fine particulate matter concentration was obtained from the Beijing Municipal Environmental Monitoring Center and the US Embassy. Twenty-four-hour ambulatory blood pressure and heart rate variability were measured from day 4. Arterial stiffness and endothelial function were obtained at the end of day 5. For statistical analysis, we used generalized additive mixed models for repeated outcomes and generalized linear models for single/summary outcomes. Mean (SD) of personal black carbon and fine particulate matter during 24 hours was 4.66 (2.89) and 64.2 (36.9) μg/m(3). Exposure to high levels of black carbon in the preceding hours was associated significantly with adverse cardiovascular responses. A unit increase in personal black carbon during the previous 10 hours was associated with an increase in systolic blood pressure of 0.53 mm Hg and diastolic blood pressure of 0.37 mm Hg (95% confidence interval, 0.17-0.89 and 0.10-0.65 mm Hg, respectively), a percentage change in low frequency to high frequency ratio of 5.11 and mean interbeat interval of -0.06 (95% confidence interval, 0.62-9.60 and -0.11 to -0.01, respectively). These findings highlight the public health effect of air pollution and the importance of reducing air pollution.

  14. Herniorrafia ambulatorial comparada à convencional Ambulatory versus conventional herniorraphy

    Directory of Open Access Journals (Sweden)

    Daniel Nunes e Silva

    2004-10-01

    Full Text Available OBJETIVO: O tratamento cirúrgico ambulatorial de hérnias inguinais é uma tendência em muitos serviços de saúde. No entanto, em nosso meio, tal procedimento ainda não perfaz uma rotina. Objetivamos analisar os benefícios e complicações da herniorrafia inguinal ambulatorial comparada à convencional. MÉTODO: Realizamos uma análise retrospectiva envolvendo, inicialmente, 105 pacientes submetidos a herniorrafia inguinal ambulatorial (HIA e internação convencional (IC de fevereiro a outubro de 2002 no Complexo Hospitalar Santa Casa de Porto Alegre (CHSCPA. Foram avaliados os benefícios e complicações no 15º, 90º e 180º dias de pós-operatório. Além disso, foi realizada avaliação dos custos hospitalares. Os métodos de análise incluíram o teste t de Fischer e X² . Foram considerados estatisticamente significativos resultados com pBACKGROUND: Ambulatory inguinal herniorraphy is performed worldwide. However, this procedure is not performed routinely in our reality. Our objetive is to analyze the benefits and complications of ambulatory inguinal herniorraphy in comparison to conventional intervention in our Service. METHODS: A retrospective analysis was performed with 105 patients who uwderwent ambulatorial or conventional inguinal herniorraphy between February and October of 2002. Variables, including costs, were analyzed at the 15th, 90th and 180th postoperative days. The Fischer's t test and chi-square test were used. Statistical significance was considered for a p value of p<0.05. RESULTS: From 105 patients, seven were excluded. The total rate complication was 36.08%. There was no significative statistical difference between groups at any time. The most common complication was local pain (24.7%. The costs decreased 20% when surgery was performed in an ambulatory basis as well as the waiting time which was also reduced. CONCLUSION: The ambulatory herniorraphy is a safe procedure, decreases hospital stay, costs and it has a

  15. National Hospital Ambulatory Medical Care Survey

    Data.gov (United States)

    U.S. Department of Health & Human Services — The National Hospital Ambulatory Medical Care Survey (NHAMCS) is designed to collect data on the utilization and provision of ambulatory care services in hospital...

  16. Biomedical Wireless Ambulatory Crew Monitor

    Science.gov (United States)

    Chmiel, Alan; Humphreys, Brad

    2009-01-01

    A compact, ambulatory biometric data acquisition system has been developed for space and commercial terrestrial use. BioWATCH (Bio medical Wireless and Ambulatory Telemetry for Crew Health) acquires signals from biomedical sensors using acquisition modules attached to a common data and power bus. Several slots allow the user to configure the unit by inserting sensor-specific modules. The data are then sent real-time from the unit over any commercially implemented wireless network including 802.11b/g, WCDMA, 3G. This system has a distributed computing hierarchy and has a common data controller on each sensor module. This allows for the modularity of the device along with the tailored ability to control the cards using a relatively small master processor. The distributed nature of this system affords the modularity, size, and power consumption that betters the current state of the art in medical ambulatory data acquisition. A new company was created to market this technology.

  17. 健康教育对健康体检人群动脉僵硬度的影响%Effect of health education in arterial stiffness of healthy subjects

    Institute of Scientific and Technical Information of China (English)

    史鸿燕; 刘金波; 王琦; 张承杰; 宋月洁; 赵红薇; 王宏宇

    2014-01-01

    目的:探讨单纯健康宣教对改善健康体检人群动脉僵硬度的作用。方法抽取2011年1月在我科进行健康体检55名,均做颈-股脉搏波传导速度( CF-PWV )及颈-桡脉搏波传导速度( CR-PWV)检测。由动脉僵硬度自动检测装置Complior测定。根据检测结果即时对受检者进行健康宣教。并对入选人群进行2年随访,分别于2012年1月、2013年1月对入选人群再次进行CR-PWV检测,将3次体检结果进行自身前后对比。计量资料的组间比较采用方差分析。结果与2011年基线检查结果相比2012及2013年的检测结果显示,受检人群体重指数[分别为(25.7±2.6)、(25.8±3.6)、(25.5±2.8) kg/m2, F =0.151, P =0.860)、收缩压分别为(137.6±12.2)、(138.6±17.1)、(140.9±14.9) mmHg, F =0.682, P =0.507]、舒张压[分别为(89.1±9.3)、(90.1±10.8)、(92.1±11.0) mmHg, F =1.232, P =0.295]、 CF-PWV [分别为(10.50±1.23) m/s (10.36±1.52) m/s、(11.54±1.32) m/s, F=1.988, P=0.596]均无明显变化,而CR-PWV呈显著降低,2013年低于2011、2012年[分别为(9.77±1.29) m/s,(10.75±1.50) m/s、(10.25±1.79) m/s、F=5.653, P=0.003]。结论单纯的健康宣教能够改善健康体检人群血管功能,在此基础上再进行切实可行、能够为广大体检人群接受的健康管理,从而真正有效的降低人群动脉硬化的进展,减少血管性疾病的发生。%Objective To investigate the effect of health education in arterial stiffness of healthysubjects.Methods Fifty-five healthy subjects from Vascular Medicine Examination in January 2011 wererandomly enrolled into our study.Carotid-femoral pulse wave velocity (carotid-femoral pulse wave velocity,CF-PWV) and carotid-radial pulse wave velocity ( carotid-radial pulse wave velocity, CR

  18. Stiffness of compression devices

    Directory of Open Access Journals (Sweden)

    Giovanni Mosti

    2013-03-01

    Full Text Available This issue of Veins and Lymphatics collects papers coming from the International Compression Club (ICC Meeting on Stiffness of Compression Devices, which took place in Vienna on May 2012. Several studies have demonstrated that the stiffness of compression products plays a major role for their hemodynamic efficacy. According to the European Committee for Standardization (CEN, stiffness is defined as the pressure increase produced by medical compression hosiery (MCH per 1 cm of increase in leg circumference.1 In other words stiffness could be defined as the ability of the bandage/stockings to oppose the muscle expansion during contraction.

  19. Relationship between Abdominal Obesity Indexes and Arterial Stiffness in Adult Chinese of Beijing%腹型肥胖测量指标与动脉硬化的相关性分析

    Institute of Scientific and Technical Information of China (English)

    王凡; 郑延松; 赛晓勇; 赵威; 李磊

    2011-01-01

    check-up during Jan 2005 to May 2010 in the health screening center of the hospital were analyzed. Obesity was evaluated by BMI, WHR and percentage of body fat (FAT%). Arterial stiffness was determined by measuring carotid-femoral (cfPWV) and carotid-radial pulse wave velocity (crPWV). Results Pearson's correlation coefficients showed that WHR was associated with cfPWV in young men and young women (r=0.191, P=0.005 vs. R=0.306, P<0.001), in middle-aged men and women (r=0.239, P<0.001 vs. R=0.189, P<0.001) and in older women (r=0.093, P=0.017), while with cfPWV and crPWV in old men (r=0.134, P=0.011 ;r=0.145, P=0.001). BMI was associated with cfPWV (r=0.175, P=0.006) in young women. FAT% was associated with crPWV in middle-aged men (r=0.186, P=0.001) and in old men (r=0.168, P=0.003), but with cfPW V and crPWV in middle-aged women (r=0.050, P=0.032; r=0.174, P=0.001) and in old women (r=0.111, P=0.009; r=0.116, P=0.015). After adjusted for blood pressure, lipids, serum sugar and uric acid, the results of multiple linear regression showed WHR was independently associated with cfPWV in middle-aged men and with cfPWV and crPWV in older men (all P<0.05). WHR was independently associated with cfPWV in different age women and FAT% was only independently associated with crPWV in older women (all P<0.05). Conclusion The results show WHR is an independent related factor for arterial stiffness in adult Chinese, whereas the BMI isn' t. And FAT% is an independent related factor for crPW V in aged women.

  20. Assessment of conduit artery vasomotion using photoplethysmography

    Science.gov (United States)

    Kanders, Karlis; Grabovskis, Andris; Marcinkevics, Zbignevs; Aivars, Juris Imants

    2013-11-01

    Vasomotion is a spontaneous oscillation of vascular tone. The phenomenon has been observed in small arterioles and capillaries as well as in the large conduit arteries. The layer of smooth muscle cells that surrounds a blood vessel can spontaneously and periodically change its tension and thereby the arterial wall stiffness also changes. As the understanding of the phenomenon is still rather obscure, researchers would benefit from a low-cost and reliable investigation technique such as photoplethysmography (PPG). PPG is an optical blood pulsation measurement technique that can offer substantial information about the arterial stiffness. The aims of this pilot study were to evaluate the usefulness of the PPG technique in the research of vasomotion and to investigate vasomotion in the relatively large conduit arteries. Continuous 15 minute long measurements of posterior tibial artery wall stiffness were taken. Artery diameter, electrocardiogram, blood pressure and respiration were also simultaneously registered. Fast Fourier Transform power spectra were calculated to identify unique stiffness oscillations that did not correspond to fluctuations in the systemic parameters and thus would indicate vasomotion. We concluded that photoplethysmography is a convenient method for the research of the vasomotion in large arteries. Local stiffness parameter b/a is more accurate to use and easier to measure than the pulse wave velocity which describes stiffness of a segment of an artery. Conduit arteries might exhibit a low amplitude high frequency vasomotion ( 9 to 27 cycles per minute). Low frequency vasomotion is problematic to distinguish from the passive oscillations imposed by the arterial pressure.

  1. Obesity and arterial compliance alterations.

    Science.gov (United States)

    Seifalian, Alexander M; Filippatos, Theodosios D; Joshi, Jatin; Mikhailidis, Dimitri P

    2010-03-01

    Obesity is associated with increased cardiovascular disease (CVD) risk, especially when excess body fat is distributed preferentially within the abdominal region. Obese subjects usually have increased arterial stiffness compared with non-obese subjects of similar age. The factors associated with increased arterial stiffness in obesity include endothelial dysfunction (decreased nitric oxide bioavailability), impaired smooth muscle cell function, insulin resistance, as well as elevated cholesterol and C-peptide levels. Furthermore, visceral fat, the adipose tissue-related renin-angiotensin-aldosterone system and hyperleptinaemia contribute to the obesity-associated impaired arterial compliance. Weight loss improves CVD risk factors and arterial compliance. Because increased arterial stiffness is a marker of CVD risk these findings support the concept that the presence of obesity has vascular implications.

  2. Posttraumatic stiff elbow

    Directory of Open Access Journals (Sweden)

    Ravi Mittal

    2017-01-01

    Full Text Available Posttraumatic stiff elbow is a frequent and disabling complication and poses serious challenges for its management. In this review forty studies were included to know about the magnitude of the problem, causes, pathology, prevention, and treatment of posttraumatic stiff elbow. These studies show that simple measures such as internal fixation, immobilization in extension, and early motion of elbow joint are the most important steps that can prevent elbow stiffness. It also supports conservative treatment in selected cases. There are no clear guidelines about the choice between the numerous procedures described in literature. However, this review article disproves two major beliefs-heterotopic ossification is a bad prognostic feature, and passive mobilization of elbow causes elbow stiffness.

  3. Posttraumatic stiff elbow

    Science.gov (United States)

    Mittal, Ravi

    2017-01-01

    Posttraumatic stiff elbow is a frequent and disabling complication and poses serious challenges for its management. In this review forty studies were included to know about the magnitude of the problem, causes, pathology, prevention, and treatment of posttraumatic stiff elbow. These studies show that simple measures such as internal fixation, immobilization in extension, and early motion of elbow joint are the most important steps that can prevent elbow stiffness. It also supports conservative treatment in selected cases. There are no clear guidelines about the choice between the numerous procedures described in literature. However, this review article disproves two major beliefs-heterotopic ossification is a bad prognostic feature, and passive mobilization of elbow causes elbow stiffness.

  4. Transient myocardial ischaemia during ambulatory monitoring out of hospital in patients with chronic stable angina pectoris

    DEFF Research Database (Denmark)

    Egstrup, K

    1988-01-01

    Transient myocardial ischaemia during daily life, detected by ambulatory electrocardiographic monitoring, was investigated in 42 patients with chronic stable angina and documented coronary artery disease. Ambulatory monitoring was initiated for 36 hours after all prophylactic antianginal medication...... had been withdrawn for 5 days. There were 196 episodes of ST-segment depression, 145 (74%) of which were not accompanied by angina. As well, a tendency to more prolonged and greater ST-segment change with symptomatic ischaemic episodes was noted. A diurnal variation in transient ischaemia both...

  5. Communication in acute ambulatory care.

    Science.gov (United States)

    Dean, Marleah; Oetzel, John; Sklar, David P

    2014-12-01

    Effective communication has been linked to better health outcomes, higher patient satisfaction, and treatment adherence. Communication in ambulatory care contexts is even more crucial, as providers typically do not know patients' medical histories or have established relationships, conversations are time constrained, interruptions are frequent, and the seriousness of patients' medical conditions may create additional tension during interactions. Yet, health communication often unduly emphasizes information exchange-the transmission and receipt of messages leading to a mutual understanding of a patient's condition, needs, and treatments. This approach does not take into account the importance of rapport building and contextual issues, and may ultimately limit the amount of information exchanged.The authors share the perspective of communication scientists to enrich the current approach to medical communication in ambulatory health care contexts, broadening the under standing of medical communication beyond information exchange to a more holistic, multilayered viewpoint, which includes rapport and contextual issues. The authors propose a socio-ecological model for understanding communication in acute ambulatory care. This model recognizes the relationship of individuals to their environment and emphasizes the importance of individual and contextual factors that influence patient-provider interactions. Its key elements include message exchange and individual, organizational, societal, and cultural factors. Using this model, and following the authors' recommendations, providers and medical educators can treat communication as a holistic process shaped by multiple layers. This is a step toward being able to negotiate conflicting demands, resolve tensions, and create encounters that lead to positive health outcomes.

  6. Modification over time of pulse wave velocity parallel to changes in aortic BP, as well as in 24-h ambulatory brachial BP.

    Science.gov (United States)

    Oliveras, A; Segura, J; Suarez, C; García-Ortiz, L; Abad-Cardiel, M; Vigil, L; Gómez-Marcos, M A; Sans Atxer, L; Martell-Claros, N; Ruilope, L M; de la Sierra, A

    2016-03-01

    Arterial stiffness as assessed by carotid-femoral pulse wave velocity (cfPWV) is a marker of preclinical organ damage and a predictor of cardiovascular outcomes, independently of blood pressure (BP). However, limited evidence exists on the association between long-term variation (Δ) on aortic BP (aoBP) and ΔcfPWV. We aimed to evaluate the relationship of ΔBP with ΔcfPWV over time, as assessed by office and 24-h ambulatory peripheral BP, and aoBP. AoBP and cfPWV were evaluated in 209 hypertensive patients with either diabetes or metabolic syndrome by applanation tonometry (Sphygmocor) at baseline(b) and at 12 months of follow-up(fu). Peripheral BP was also determined by using validated oscillometric devices (office(o)-BP) and on an outpatient basis by using a validated (Spacelabs-90207) device (24-h ambulatory BP). ΔcfPWV over time was calculated as follows: ΔcfPWV=[(cfPWVfu-cfPWVb)/cfPWVb] × 100. ΔBP over time resulted from the same formula applied to BP values obtained with the three different measurement techniques. Correlations (Spearman 'Rho') between ΔBP and ΔcfPWV were calculated. Mean age was 62 years, 39% were female and 80% had type 2 diabetes. Baseline office brachial BP (mm Hg) was 143±20/82±12. Follow-up (12 months later) office brachial BP (mm Hg) was 136±20/79±12. ΔcfPWV correlated with ΔoSBP (Rho=0.212; P=0.002), Δ24-h SBP (Rho=0.254; PSBP (Rho=0.232; P=0.001), Δnighttime SBP (Rho=0.320; PSBP, Δdaytime SBP, Δnighttime SBP and ΔaoSBP. ΔcfPWV was independently associated with Δ24-h SBP (β-coefficient=0.195; P=0.012) and ΔaoSBP (β-coefficient= 0.185; P=0.018). We conclude that changes in both 24-h SBP and aoSBP more accurately reflect changes in arterial stiffness than do office BP measurements.

  7. Towards ambulatory mental stress measurement from physiological parameters

    NARCIS (Netherlands)

    Wijsman, Jacqueline; Vullers, Ruud; Polito, Salvatore; Agell, Carlos; Penders, Julien; Hermens, Hermie

    2013-01-01

    Ambulatory mental stress monitoring requires longterm physiological measurements. This paper presents a data collection protocol for ambulatory recording of physiological parameters for stress measurement purposes. We present a wearable sensor system for ambulatory recording of ECG, EMG, respiration

  8. Relationship of 24-hour urinary sodium-to-potassium excretion with blood pressure and arterial stiffness in hypertensive patients%高血压人群中24h尿钠钾水平与血压和动脉僵硬度的关系

    Institute of Scientific and Technical Information of China (English)

    韩伟中; 孙宁玲

    2012-01-01

    目的 探索高血压人群中尿钠、尿钾和尿钠钾比值水平与血压和动脉僵硬度的关系.方法 入选未服用降压药的高血压患者224例,按照标准留取24 h尿标本,检测尿钾、尿钠含量和尿钠钾比值.根据24 h尿钠水平分为3组,尿钠≤100 mmol/24 h(A组)、>100~200(B组)和>200 mmol/24 h组(C组).对上述患者进行24 h动态血压监测和臂踝动脉脉搏波传导速度(baPWV)检查.结果 人群平均24 h尿钠值为(160.0±69.4)mmol/24 h,所对应食盐摄入量为9.6 g/d,平均尿钠钾比值为4.8.A、B、C3组人群的平均尿钠值分别为(84.9±12.7)、(147.0±26.7)和(256.1±42.6)mmol/24 h,所对应平均摄盐量为5.1、8.8和15.3 g/d.C组24 h、白昼、夜间收缩压、舒张压明显高于A组(P<0.01).全人群多元线性回归分析显示,尿钠和钠钾比值与24 h收缩压、舒张压以及脉压呈正相关(β值分别为0.221、0.188,0146、0.211,0.136、0.142,均P<0.05).A、B、C3组人群的baPWV分别为(1621.6±288.3)、(1645.7±301.0)和(1741.9±307.0)cm/s,C组明显高于A组和B组(P=0.032,P=0.046),多元线性回归分析显示,尿钠和钠钾比值是baPWV的独立影响因素(β值分别为0.126,0.158,均P<0.05).结论 尿钠和钠钾比值不仅与血压水平密切相关,而且与baPWV密切相关,这种关系是独立于血压作用之外的.%Objective To explore the relationship of 24-hour urinary sodium, urinary potassium and urinary sodium/ potassium excretion with blood pressure and arterial stiffness in hypertension patients. Methods A total of 224 patients with untreated hypertension were recruited. 24-hour urine specimens were collected for detecting urinary sodium, urinary potassium and urinary sodium/potassium ratio. According to the level of 24-hour urinary sodium,the patients were divided into three groups:group A(urinary sodium≤100 mmol/24 h) , group B(urinary sodium 100-200 mmol/24 h) and group C(urinary sodium>200 mmol/24 h). All the subjects

  9. MIGRAINE, CAROTID STIFFNESS AND GENETIC POLYMORPHISM.

    Science.gov (United States)

    Kes, Vanja Basić; Jurasić, Miljenka-Jelena; Zavoreo, Iris; Corić, Lejla; Rotim, Kresimir

    2015-12-01

    Recently migraine has been associated with increased arterial stiffness, procoagulant state, increased incidence of cerebral white matter lesions (WML) and stroke. Our aim was to compare the characteristics of migraineurs to headache free controls regarding their functional carotid ultrasound parameters. Sixty patients (45 women) with migraine (mean age 40.42 ± 10.61 years) were compared with 45 controls (30 women) with no prior history of repeating headache (mean age 38.94 ± 5.46 years) using E-tracking software on Alpha 10 ultrasound platform. Student's t-test was used on statistical analysis with alpha < 0.05. All tested carotid vascular parameters were worse in patients with migraine including increased intima-media thickness, greater carotid diameter and carotid diameter change, as well as several arterial stiffness indices. Additionally, patients with migraine had greater incidence of homozygous mutations for procoagulant genes (MTHFR (C677T), PAI-1 and ACE I/D) than expected. Computed tomography and magnetic resonance imaging of the brain showed WML in 11 patients, four of them migraine with aura patients. Since we established increased carotid stiffness and higher frequency of procoagulant gene mutations in migraineurs, we propose prospective ultrasound monitoring in such patients, especially those with detected WML, in order to timely commence more active and specific preventive stroke management strategies.

  10. Ambulatory spine surgery: a survey study.

    Science.gov (United States)

    Baird, Evan O; Brietzke, Sasha C; Weinberg, Alan D; McAnany, Steven J; Qureshi, Sheeraz A; Cho, Samuel K; Hecht, Andrew C

    2014-08-01

    Study Design Cross-sectional study. Objective To assess the current practices of spine surgeons performing ambulatory surgery in the United States. Methods An electronic survey was distributed to members of the International Society for the Advancement of Spine Surgery. Data were initially examined in a univariate manner; variables with a p value ambulatory spine surgery, and 49.1% were investors in an ambulatory surgery center. Surgeon investors in ambulatory surgery centers were more likely to perform procedures of increased complexity than noninvestors, though limited data precluded a statistical correlation. Surgeons in private practice were more likely to perform ambulatory surgery (94.3%; p = 0.0176), and nonacademic surgeons were both more likely to invest in ambulatory surgery centers (p = 0.0024) and perform surgery at least part of the time in a surgery center (p = 0.0039). Conclusions Though the numbers were too few to calculate statistical significance, there was a trend toward the performance of high-risk procedures on an ambulatory basis being undertaken by those with investment status in an ambulatory center. It is possible that this plays a role in the decision to perform these procedures in this setting versus that of a hospital, where a patient may have better access to care should a complication arise requiring emergent assessment and treatment by a physician. This decision should divest itself of financial incentives and focus entirely on patient safety.

  11. Optimizing anesthesia techniques in the ambulatory setting

    NARCIS (Netherlands)

    E. Galvin

    2007-01-01

    textabstractAmbulatory surgery refers to the process of admitting patients, administering anesthesia and surgical care, and discharging patients home following an appropriate level of recovery on the same day. The word ambulatory is derived from the latin word ambulare, which means ''to walk''. This

  12. Stiff Quantum Polymers

    OpenAIRE

    Kleinert, H

    2007-01-01

    At ultralow temperatures, polymers exhibit quantum behavior, which is calculated here for the second and fourth moments of the end-to-end distribution in the large-stiffness regime. The result should be measurable for polymers in wide optical traps.

  13. Dynamic stiffness of suction caissons

    DEFF Research Database (Denmark)

    Ibsen, Lars Bo; Liingaard, Morten; Andersen, Lars

    The purpose of this report is to evaluate the dynamic soil-structure interaction of suction caissons for offshore wind turbines. The investigation is limited to a determination of the vertical dynamic stiffness of suction caissons. The soil surrounding the foundation is homogenous with linear...... of the skirt length, Poisson's ratio and the ratio between soil stiffness and skirt stiffness. Finally the dynamic behaviour at high frequencies is investigated....... viscoelastic properties. The dynamic stiffness of the suction caisson is expressed by dimensionless frequency-dependent dynamic stiffness coefficients corresponding to the vertical degree of freedom. The dynamic stiffness coefficients for the foundations are evaluated by means of a dynamic three...

  14. Blood cultures in ambulatory outpatients

    Directory of Open Access Journals (Sweden)

    Laupland Kevin B

    2005-05-01

    Full Text Available Abstract Background Blood cultures are a gold standard specific test for diagnosing many infections. However, the low yield may limit their usefulness, particularly in low-risk populations. This study was conducted to assess the utility of blood cultures drawn from ambulatory outpatients. Methods Blood cultures drawn at community-based collection sites in the Calgary Health Region (population 1 million in 2001 and 2002 were included in this study. These patients were analyzed by linkages to acute care health care databases for utilization of acute care facilities within 2 weeks of blood culture draw. Results 3102 sets of cultures were drawn from 1732 ambulatory outpatients (annual rate = 89.4 per 100,000 population. Significant isolates were identified from 73 (2.4% sets of cultures from 51 patients, including Escherichia coli in 18 (35% and seven (14% each of Staphylococcus aureus and Streptococcus pneumoniae. Compared to patients with negative cultures, those with positive cultures were older (mean 49.6 vs. 40.1 years, p Conclusion Blood cultures drawn in outpatient settings are uncommonly positive, but may define patients for increased intensity of therapy. Strategies to reduce utilization without excluding patients with positive cultures need to be developed for this patient population.

  15. Genetics of Stiff Child Syndrome

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2005-11-01

    Full Text Available A Chinese boy with a DYT1 gene mutation presented with muscle stiffness, painful muscle spasms, myoclonus, and dystonia, compatible with stiff child syndrome, and is reported from Queen Mary Hospital, the University of Hong Kong.

  16. On gear tooth stiffness evaluation

    DEFF Research Database (Denmark)

    Pedersen, Niels Leergaard; Jørgensen, Martin Felix

    2014-01-01

    The estimation of gear stiffness is important for determining the load distribution between the gear teeth when two sets of teeth are in contact. Two factors have a major influence on the stiffness; firstly the boundary condition through the gear rim size included in the stiffness calculation...... and secondly the size of the contact. In the FE calculation the true gear tooth root profile is applied. The meshing stiffnesses of gears are highly non-linear, it is however found that the stiffness of an individual tooth can be expressed in a linear form assuming that the contact width is constant. © 2014...

  17. [Measurement of arterial pressure].

    Science.gov (United States)

    Rorive, G

    1998-03-01

    The casual determination of blood pressure remains the basis of the diagnosis of arterial hypertension and the criteria for usefulness of drug therapy. The reference values usually in use concern determinations by the doctor in very well defined conditions, rest, size of the bladder, etc.... The poor reproductibility of the determinations made by the doctor in casual conditions has produced a large interest for new approaches: autodetermination by the patient at home, and ambulatory blood pressure determinations using automatic devices. These new approaches have their own reference values, specific indications and limitations.

  18. National Ambulatory Medical Care Survey (NAMCS)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The National Ambulatory Medical Care Survey (NAMCS) is a national survey designed to meet the need for objective, reliable information about the provision and use of...

  19. NAFLD and Increased Aortic Stiffness: Parallel or Common Physiopathological Mechanisms?

    Science.gov (United States)

    Villela-Nogueira, Cristiane A.; Leite, Nathalie C.; Cardoso, Claudia R. L.; Salles, Gil F.

    2016-01-01

    Non-alcoholic fatty liver disease (NAFLD) has become the leading cause of chronic liver diseases worldwide. Liver inflammation and fibrosis related to NAFLD contribute to disease progression and increasing liver-related mortality and morbidity. Increasing data suggest that NAFLD may be linked to atherosclerotic vascular disease independent of other established cardiovascular risk factors. Central arterial stiffness has been recognized as a measure of cumulative cardiovascular risk marker load, and the measure of carotid-femoral pulse wave velocity (cf-PWV) is regarded as the gold standard assessment of aortic stiffness. It has been shown that increased aortic stiffness predicts cardiovascular morbidity and mortality in several clinical settings, including type 2 diabetes mellitus, a well-known condition associated with advanced stages of NAFLD. Furthermore, recently-published studies reported a strong association between NAFLD and increased arterial stiffness, suggesting a possible link in the pathogenesis of atherosclerosis and NAFLD. We sought to review the published data on the associations between NAFLD and aortic stiffness, in order to better understand the interplay between these two conditions and identify possible common physiopathological mechanisms. PMID:27104526

  20. Meta Analysis of the Changes of Arterial Stiffness of Hypertension Patients with CCB or ARB%钙离子拮抗剂和血管紧张素Ⅱ受体阻断剂对高血压患者动脉僵硬度影响的Meta分析

    Institute of Scientific and Technical Information of China (English)

    张艺军; 裴静娴; 吴平生

    2012-01-01

    目的 系统评价钙离子拮抗剂(CCB)和血管紧张素Ⅱ受体阻断剂(ARB)对高血压患者血管功能的作用差异.方法 按循证医学的要求,制定相应的纳入、排除标准及其检索策略.通过PubMed、Embase、Ovid EMBReviews、中国期刊全文数据库、中文科技期刊全文数据库、万方数据库检索相关的临床对照研究,检索各数据库从建库至2012年1月;纳入CCB和ARB治疗原发性高血压的随机对照试验.采用RevMan5.0软件进行统计分析.比较CCB和ARB对高血压患者脉搏波传导速度、收缩压、舒张压、脉压等指标的影响.结果 共纳入6个随机对照试验,共计411例患者.Meta分析结果显示,ARB在改善动脉僵硬度方面优于CCB(均数差为183.33,95% CI为79.32 ~ 287.33),差异有统计学意义.但是在降低收缩压(均数差为-2.66,95% CI为-3.35 ~-1.96)和舒张压(均数差为-5.43,95% CI为-8.8 ~-2.07)方面较CCB弱.结论 ARB在改善高血压患者动脉僵硬度方面优于CCB,该作用与其降压作用无关.但仍需要大样本多中心的随机对照临床试验来进一步证实.%Aim To evaluate the differences of the changes of arterial stiffness of hypertension patients with the treatment of calcium channel blocker ( CCB) or angiotensin Ⅱ receptor blocker ( ARB) . Methods Based on the principles of evidence-based medicine, corresponding inclusion and exclusion criteria, along with search strategies were developed. We searched the Ovid EMB Reviews, Pubmed, EMBASE, Chinese Biomedical Literature Database, Chinese Scientific Journal Full-text Database, and Chinese Journal Full-text Database up to January 2012 to identify randomized controlled trials ( RCT) comparing the effects of CCB with that of ARB on arterial stiffness of hypertension patients. Two reviewers independently evaluated the quality of the included studies, extracted data with a unified form, and analyzed the data by Cochrane Collaboration' s RevMan 5. 0

  1. 血管回声跟踪技术评价抗氧化剂干预吸烟对肱动脉弹性的影响%Echo-tracking technique in evaluation on effects of antioxidant to smoking-induced brachial arterial wall stiffness in healthy volunteers

    Institute of Scientific and Technical Information of China (English)

    薛莉; 罗春英; 王谦谦; 李学奇; 申宝忠

    2011-01-01

    Objective To investigate whether the oral administration of vitamin C (Vit C ) can prevent the smoking-induced acceleration arterial stiff'ness in short -term smoking healthy volunteers with echo -tracking (ET ) technique . Methods Sixty healthy smokers were enrolled and divided into treatment group (oral administrating Vit C ) and control group (oral administrating placebo ) . ET technique was used to measure the parameters of elasticity of brachial artery including stiffness (β) , pressure strain elastic modulus (Ep) , arterial compliance (AC ) . The hlood pressure and heart rate before and after smoking in healthy volunteers were also measured . Results In treatment group , β , Ep of brachial artery increased and AC decreased immediately after smoking than those before smoking ( P< 0. 05 ) . The level of β, Ep and AC measured at 5 min after smoking had no difference with those measured before smoking . In control group , β , Ep increased significantly and AC decreased significantly at O , 5 , 10 min after smoking than those before smoking ( P< 0. 05 ) . The level of β, Ep and AC measured at 15 min after smoking had no difference with those measured before smoking . The level ofβ , Ep in treatment group were lower than those in control group at 0 , 5 . 10 min after smoking ( P<0. 05 ) , w hile AC measured at 0 , 5 min after smoking were higher than those in control group ( P< 0. 05 ) . The changes of blood pressure and heart rate had no difference between the two groups (all P>0. 05 ) . Conclusion Smoking may lead to acute transient increase in blood pressure , heart rate and elasticity of branchial artery . Single-dose oral administrating Vit C may ameliorate the smoking-induced aaleleration arterial stiffness in healthy volunteers , but has no intervention effect on blood pressure and heart rate .%目的 应用血管回声跟踪(ET)技术探讨单剂口服维生素C(Vit C)拮抗吸烟对短期吸烟者肱动脉弹性的影响.方法 60名健康

  2. Evaluating changes of carotid artery in patients with impaired glucose tolerance and type 2 diabetes mellitus with quantitative intima-media thickness and quantitative arterial stiffness%内中膜厚度定量及动脉僵硬度分析技术评价糖耐量减低及2型糖尿病者颈总动脉改变

    Institute of Scientific and Technical Information of China (English)

    谭丽芳; 艾红; 王娟; 石秀英; 淡敏

    2012-01-01

    目的 应用血管内中膜厚度定量(QIMT)及动脉僵硬度分析(QAS)技术评价糖耐量减低(IGT)和2型糖尿病(T2DM)患者颈总动脉结构及功能的改变.方法 对病例组68例患者[30例IGT(IGT亚组)和38例T2DM(T2DM亚组)]及58名正常对照(NC)组的右侧颈总动脉行QIMT、QAS及相关血清学检查,获取以下参数:内中膜厚度(IMT)、顺应性系数(CC)、扩张性系数(DC)、僵硬度参数(β)、2 h血糖值(2hPG)、甘油三酯(TG),胆固醇(Ch),低密度脂蛋白(LDL),糖化血红蛋白(GHb),并分析NC组与病例组各亚组之间的差异及相关性.结果 T2DM亚组DC低于NC组(P<0.05),其余参数组间两两比较差异均有统计学意义(P均<0.05);IGT和T2DM亚组β和IMT、2hPG、LDL与GHb均呈正相关(P均<0.01).结论 QIMT及QAS技术可反映动脉血管的早期结构及功能变化,对诊断IGT及T2DM患者早期动脉粥样硬化具有一定价值.%Objective To investigate the structural and functional changes of carotid artery in patients with type 2 diabetes mellitus (T2DM) and impaired glucose tolerance (IGT) with quantitative intima-media thickness (QIMT) and quantitative arterial stiffness (QAS) technique. Methods The right side-of common carotid artery of 68 patients (30 IGT and 38 T2DM ) and 58 healthy controls (NC group) were examined with QIMT, QAS technique and relative serological testing. Parameters including triglyceride (TG), low-density lipoprotein ( LDL) , cholesterol (Ch), glycosylated hemoglobin (GHb), intima-media thickness (IMT), compliance coefficient (CO, distensibility coefficient (DC), stiffness index (β) and 2 h plasma glucose (2hPG) of carotid obtained were acquired and the statistically analyzed. Results DC in T2DM subgroup was lower than in NC group, while the other parameters all had statistical differences among groups (all P<0. 05). There was positive correlation between β and IMT, 2hPG. LDL, GHb in IGT and T2DM subgroup (all P<0. 01). Conclusion QIMT and QAS

  3. HCUP State Ambulatory Surgery Databases (SASD) - Restricted Access Files

    Data.gov (United States)

    U.S. Department of Health & Human Services — The State Ambulatory Surgery Databases (SASD) contain the universe of hospital-based ambulatory surgery encounters in participating States. Some States include...

  4. Ambulatory ST segment monitoring after myocardial infarction

    DEFF Research Database (Denmark)

    Mickley, H

    1994-01-01

    ischaemia provides prognostic information in different subsets of patients with previous myocardial infarction, but there is considerable disagreement about how this is expressed in terms of cardiac events. Small patient numbers, patient selection, and different timing of ambulatory monitoring are proposed...... as important reasons for the inconsistent findings. The precise role of ambulatory ST segment monitoring in clinical practice has yet to be established. Direct comparisons with exercise stress testing may not be appropriate for two reasons. Firstly, the main advantage of ambulatory monitoring may...... be that it can be performed early after infarction at the time of maximum risk. Secondly, it can be performed in most patients after infarction, including those recognised as being at high risk who are unable to perform an exercise stress test....

  5. Relations between a novel, reliable, and rapid index of arterial compliance (PP-HDI) and well-established inidices of arterial blood pressure (ABP) in a sample of hypertensive elderly subjects.

    Science.gov (United States)

    Bergamini, L; Finelli, M E; Bendini, C; Ferrari, E; Veschi, M; Neviani, F; Manni, B; Pelosi, A; Rioli, G; Neri, M

    2009-01-01

    Hypertension is a risk factor for a long-lasting arterial wall-remodelling leading to stiffness. The rapid method measuring the pulse pressure (PP) by means of the tool of Hypertension Diagnostic Instruments (HDI) called PP-HDI, overcomes some of the problems arising with more-time consuming methods, like ambulatory blood pressure monitoring (ABPM), and give information about the elasticity of the arterial walls. We studied the relationship between the PP-HDI, the large artery compliance (LA-C) and small artery compliance (SA-C) and few well-established indices of arterial blood pressure (ABP) in a sample of 75 hypertensive subjects, aged 65 years and over. Significant correlations between LA-C and heart rate (HR), PP-ABPM and PP-HDI were found. SA-C relates with HR and systolic blood pressure (SBP) measured in lying and standing positions. Applying a stepwise regression analysis, we found that LA-C variance stems from PP-HDI and HR, while SA-C variance stems from SBP in lying position. Receiver operator characteristic (ROC) curves for thresholds of PP showed that PP-HDI reached levels of sensitivity/specificity similar to PP-ABPM. In conclusion, surveillance of ABP through hemo-dynamic indices, in particular of SBP, is essential, nevertheless the advantage of this control is not known in an elderly population where the organ damage is already evident. PP needs necessarily an instrumental measurement. The PP-HDI result is similar in reliability with respect to PPABPM, but is more rapid and well applicable in an elderly population.

  6. Arterial function of carotid and brachial arteries in postmenopausal vegetarians

    Directory of Open Access Journals (Sweden)

    Su T

    2011-08-01

    Full Text Available Ta-Chen Su1, Pao-Ling Torng2, Jiann-Shing Jeng3, Ming-Fong Chen1, Chiau-Suong Liau1,41Division of Cardiology, Department of Internal Medicine, 2Department of Obstetrics and Gynecology, 3Department of Neurology, National Taiwan University Hospital, National Taiwan University College of Medicine, 4Cardiovascular Center, Taipei Buddist Tzu-Chi Hospital, Hsin-Dian, Taipei, TaiwanBackground: Vegetarianism is associated with a lower risk of cardiovascular disease. However, studies of arterial function in vegetarians are limited.Methods: This study investigated arterial function in vegetarianism by comparing 49 healthy postmenopausal vegetarians with 41 age-matched omnivores. The arterial function of the common carotid artery was assessed by carotid duplex, while the pulse dynamics method was used to measure brachial artery distensibility (BAD, compliance (BAC, and resistance (BAR. Fasting blood levels of glucose, lipids, lipoprotein (a, high-sensitivity C-reactive protein, homocysteine, and vitamin B12 were also measured.Results: Vegetarians had significantly lower serum cholesterol, high-density and low-density lipoprotein, and glucose compared with omnivores. They also had lower vitamin B12 but higher homocysteine levels. Serum levels of lipoprotein (a and high-sensitivity C-reactive protein were no different between the two groups. There were no significant differences in carotid beta stiffness index, BAC, and BAD between the two groups even after adjustment for associated covariates. However, BAR was significantly lower in vegetarians than in omnivores. Multiple linear regression analysis revealed that age and pulse pressure were two important determinants of carotid beta stiffness index and BAD. Vegetarianism is not associated with better arterial elasticity.Conclusion: Apparently healthy postmenopausal vegetarians are not significantly better in terms of carotid beta stiffness index, BAC, and BAD, but have significantly decreased BAR than

  7. Meta Analysis of the Effects of Calcium Channel Blockers or Renin-Angiotensin System Blockers on Arterial Stiffness in Hypertension%钙离子拮抗剂和肾素-血管紧张素系统阻断剂对高血压动脉僵硬度作用差异的荟萃分析

    Institute of Scientific and Technical Information of China (English)

    张艺军; 裴静娴; 王月刚; 吴平生

    2012-01-01

    -angiotensin system Mockers on arterial stiffness of hypertension patients after more than 12 weeks treatment. Analyzed the data by Cochrane Collaboration's RevMan 5.0 software. We performed the comparisons of the effects of calcium channel blockers and Renin-angiotensin system blockers on arterial stiffness, systolic blood pressure, diastolic blood pressure and pulse pressure in hypertension patients. Results Seven randomized controlled trials involving 524 patients were included. The results of meta analysis showed that Renin-angiotensin system blockers was better than calcium channel blockers in reducing arterial stiffness (MD = 160.15, 95%CI 57.10-263.21), but it was weaker than calcium channel blockers in reducing systolic blood pressure (MD=-2.94, 95%CI-4.59~-1.29)and diastolic blood pressure (MD=-6.63, 95%CI -9.56-3.70). There is no significant difference in pulse pressure between the two drugs (MD=-6.12,95%CI-2.3~14.55). Conclusions The effect of Renin-angiotensin system blockers is stronger than that of calcium channel blockers on reducing arterial stiffness in hypertension patients, and was independent of reduction in blood pressure by these drugs.

  8. A Reply to Stiff and Boster.

    Science.gov (United States)

    Petty, Richard E.; And Others

    1987-01-01

    Addresses the major errors and misconceptions perpetuated by Stiff and Boster's response to criticism of Stiff's 1986 article. Focuses on the major conceptual and methodological issues of Stiff's model. (NKA)

  9. Stiffness of desiccating insect wings

    Energy Technology Data Exchange (ETDEWEB)

    Mengesha, T E; Vallance, R R [Department of Mechanical Engineering, The George Washington University, 738 Phillips Hall, 801 22nd St NW, Washington, DC 20052 (United States); Mittal, R, E-mail: vallance@gwu.edu [Department of Mechanical Engineering, Johns Hopkins University, 126 Latrobe Hall, 3400 N Charles Street, Baltimore, MD 21218 (United States)

    2011-03-15

    The stiffness of insect wings is typically determined through experimental measurements. Such experiments are performed on wings removed from insects. However, the wings are subject to desiccation which typically leads to an increase in their stiffness. Although this effect of desiccation is well known, a comprehensive study of the rate of change in stiffness of desiccating insect wings would be a significant aid in planning experiments as well as interpreting data from such experiments. This communication presents a comprehensive experimental analysis of the change in mass and stiffness of gradually desiccating forewings of Painted Lady butterflies (Vanessa cardui). Mass and stiffness of the forewings of five butterflies were simultaneously measured every 10 min over a 24 h period. The averaged results show that wing mass declined exponentially by 21.1% over this time period with a time constant of 9.8 h, while wing stiffness increased linearly by 46.2% at a rate of 23.4 {mu}N mm{sup -1} h{sup -1}. For the forewings of a single butterfly, the experiment was performed over a period of 1 week, and the results show that wing mass declined exponentially by 52.2% with a time constant of 30.2 h until it reached a steady-state level of 2.00 mg, while wing stiffness increased exponentially by 90.7% until it reached a steady-state level of 1.70 mN mm{sup -1}. (communication)

  10. Fibulin-1 is a marker for arterial extracellular matrix alterations in type 2 diabetes

    DEFF Research Database (Denmark)

    Cangemi, Claudia; Skov, Vibe; Poulsen, Michael Kjaer

    2011-01-01

    Extracellular matrix alterations are important elements in the arterial changes seen in diabetes, being associated with increased vascular stiffness and the development of cardiovascular diseases. However, no biomarkers for diabetes-related arterial changes have been defined.......Extracellular matrix alterations are important elements in the arterial changes seen in diabetes, being associated with increased vascular stiffness and the development of cardiovascular diseases. However, no biomarkers for diabetes-related arterial changes have been defined....

  11. Analytical theory for shape stiffness

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The shape stiffness of mill m is defined as the crosswise rigidity of the unit width of steel plate, that is, m=k/b. By differentiating the steel plate crown equation in the vector model of steel plate shape, a new concise equation for the shape stiffness, kc=m+q, is obtained. Furthermore, by combining the calculation equation for steel plate crown derived from Castigliano's theorem, an analytical calculation equation for the shape rigidity of rolled steel plate is derived. The correctness and practicability of the theory for the shape stiffness are demonstrated by comparing the results from the numerical calculation with the practical data of a rolling mill.

  12. Analytical theory for shape stiffness

    Institute of Scientific and Technical Information of China (English)

    张进之

    2000-01-01

    The shape stiffness of mill m is defined as the crosswise rigidity of the unit width of steel plate, that is, m = k/b. By differentiating the steel plate crown equation in the vector model of steel plate shape, a new concise equation for the shape stiffness, kc = m + q, is obtained. Furthermore, by combining the calculation equation for steel plate crown derived from Castigliano’s theorem, an analytical calculation equation for the shape rigidity of rolled steel plate is derived. The correctness and practicability of the theory for the shape stiffness are demonstrated by comparing the results from the numerical calculation with the practical data of a rolling mill.

  13. Clinical Assessment Applications of Ambulatory Biosensors

    Science.gov (United States)

    Haynes, Stephen N.; Yoshioka, Dawn T.

    2007-01-01

    Ambulatory biosensor assessment includes a diverse set of rapidly developing and increasingly technologically sophisticated strategies to acquire minimally disruptive measures of physiological and motor variables of persons in their natural environments. Numerous studies have measured cardiovascular variables, physical activity, and biochemicals…

  14. Ambulatory Care Skills: Do Residents Feel Prepared?

    Directory of Open Access Journals (Sweden)

    Denise Bonds

    2002-10-01

    Full Text Available Objective: To determine resident comfort and skill in performing ambulatory care skills. Methods: Descriptive survey of common ambulatory care skills administered to internal medicine faculty and residents at one academic medical center. Respondents were asked to rate their ability to perform 12 physical exam skills and 6 procedures, and their comfort in performing 7 types of counseling, and obtaining 6 types of patient history (4 point Likert scale for each. Self-rated ability or comfort was compared by gender, status (year of residency, faculty, and future predicted frequency of use of the skill. Results: Residents reported high ability levels for physical exam skills common to both the ambulatory and hospital setting. Fewer felt able to perform musculoskeletal, neurologic or eye exams easily alone. Procedures generally received low ability ratings. Similarly, residents’ comfort in performing common outpatient counseling was also low. More residents reported feeling very comfortable in obtaining history from patients. We found little variation by gender, year of training, or predicted frequency of use. Conclusion: Self-reported ability and comfort for many common ambulatory care skills is low. Further evaluation of this finding in other training programs is warranted.

  15. Planning an ambulatory care joint venture.

    Science.gov (United States)

    Harpster, L M

    1988-01-01

    This article discusses ambulatory care joint ventures by hospitals and selected members of their medical staffs and emphasizes the resolution of problems in the early planning stages. Failure to follow an orderly and thoughtful planning process not only risks valuable resources of the venture partners, but also jeopardizes the working relationship between the hospital and its medical staff.

  16. Regional anesthesia techniques for ambulatory orthopedic surgery.

    LENUS (Irish Health Repository)

    O'Donnell, Brian D

    2012-02-03

    PURPOSE OF REVIEW: The purpose of this review is to present advances in the use of regional anesthetic techniques in ambulatory orthopedic surgery. New findings regarding the use of both neuraxial anesthesia and peripheral nerve block are discussed. RECENT FINDINGS: Neuraxial anesthesia: The use of short-acting local anesthetic agents such as mepivacaine, 2-chloroprocaine, and articaine permits rapid onset intrathecal anesthesia with early recovery profiles. Advantages and limitations of these agents are discussed.Peripheral nerve block: Peripheral nerve blocks in limb surgery have the potential to transform this patient cohort into a truly ambulatory, self-caring group. Recent trends and evidence regarding the benefits of regional anesthesia techniques are presented.Continuous perineural catheters permit extension of improved perioperative analgesia into the ambulatory home setting. The role and reported safety of continuous catheters are discussed. SUMMARY: In summary, shorter acting, neuraxial, local anesthetic agents, specific to the expected duration of surgery, may provide superior recovery profiles in the ambulatory setting. A trend towards more peripheral and selective nerve blocks exists. The infrapatellar block is a promising technique to provide analgesia following knee arthroscopy. Improved analgesia seen in the perioperative period can be safely and effectively extended to the postoperative period with the use of perineural catheters.

  17. Predicting recovery at home after Ambulatory Surgery

    Directory of Open Access Journals (Sweden)

    Ayala Guillermo

    2011-10-01

    Full Text Available Abstract The correct implementation of Ambulatory Surgery must be accompanied by an accurate monitoring of the patient post-discharge state. We fit different statistical models to predict the first hours postoperative status of a discharged patient. We will also be able to predict, for any discharged patient, the probability of needing a closer follow-up, or of having a normal progress at home. Background The status of a discharged patient is predicted during the first 48 hours after discharge by using variables routinely used in Ambulatory Surgery. The models fitted will provide the physician with an insight into the post-discharge progress. These models will provide valuable information to assist in educating the patient and their carers about what to expect after discharge as well as to improve their overall level of satisfaction. Methods A total of 922 patients from the Ambulatory Surgery Unit of the Dr. Peset University Hospital (Valencia, Spain were selected for this study. Their post-discharge status was evaluated through a phone questionnaire. We pretend to predict four variables which were self-reported via phone interviews with the discharged patient: sleep, pain, oral tolerance of fluid/food and bleeding status. A fifth variable called phone score will be built as the sum of these four ordinal variables. The number of phone interviews varies between patients, depending on the evolution. The proportional odds model was used. The predictors were age, sex, ASA status, surgical time, discharge time, type of anaesthesia, surgical specialty and ambulatory surgical incapacity (ASI. This last variable reflects, before the operation, the state of incapacity and severity of symptoms in the discharged patient. Results Age, ambulatory surgical incapacity and the surgical specialty are significant to explain the level of pain at the first call. For the first two phone calls, ambulatory surgical incapacity is significant as a predictor for all

  18. Level Classifications of Foundation Stiffness

    DEFF Research Database (Denmark)

    Ibsen, Lars Bo; Liingaard, Morten

    2007-01-01

    This article describes a foundation module developed and implemented in both HAWC and FLEX capable of to simulate the frequency dependent stiffness and damping of foundations e.g. pile, gravitation and bucket foundations.......This article describes a foundation module developed and implemented in both HAWC and FLEX capable of to simulate the frequency dependent stiffness and damping of foundations e.g. pile, gravitation and bucket foundations....

  19. Outcome-driven thresholds for ambulatory pulse pressure in 9938 participants recruited from 11 populations

    DEFF Research Database (Denmark)

    Gu, Yu-Mei; Thijs, Lutgarde; Li, Yan

    2014-01-01

    Evidence-based thresholds for risk stratification based on pulse pressure (PP) are currently unavailable. To derive outcome-driven thresholds for the 24-hour ambulatory PP, we analyzed 9938 participants randomly recruited from 11 populations (47.3% women). After age stratification (... years) and using average risk as reference, we computed multivariable-adjusted hazard ratios (HRs) to assess risk by tenths of the PP distribution or risk associated with stepwise increasing (+1 mm Hg) PP levels. All adjustments included mean arterial pressure. Among 6028 younger participants (68 853...

  20. Effect of Combination of Antihypertensive and Lipid Lowering Therapy on Arterial Stiffness in Elderly Patients with Mild to Moderate Essential Hypertension%降压降脂联合治疗对老年高血压患者动脉僵硬度的影响

    Institute of Scientific and Technical Information of China (English)

    胡小亮; 路方红; 刘振东; 赵颖馨; 孙尚文; 王舒健

    2011-01-01

    目的 探讨降压降脂联合治疗对老年高血压患者动脉僵硬度的影响.方法 纳入轻、中度老年高血压患者216例,给予双氢克尿噻( 25 mg/d)作为基础治疗,2周后随机分为4组,每组54例,分别为强化降压降脂组(双氢克尿噻25 mg/d,坎地沙坦8 mg/d,瑞舒伐他汀10 mg/d)、强化降压组(双氢克尿噻25 mg/d,坎地沙坦8 mg/d)、降压降脂组(双氢克尿噻25 mg/d,瑞舒伐他汀10 mg/d)和对照组(双氢克尿噻25 mg/d).治疗12个月后比较4组测量血压(BP)、血生化、颈桡动脉脉搏波传导速度(crPWV)的变化.结果 治疗12个月后,4组SBP、DBP、PP、crPWV均较治疗前明显降低(P<0.05),其中降压降脂联合治疗对降低老年高血压患者SBP、DBP、PP、CrPWV存在交互作用,F值分别为40.765、4.869、24.829和53.149,P值均<0.05.结论 降压联合降脂治疗能显著降低老年高血压患者的颈桡脉搏波传导速度,改善动脉僵硬度,优于单一降压或降脂治疗.%Objective To observe the effect of combination of antihypertensive and lipid lowering therapy on arterial stiffness in elderly patients with mild to moderate essential hypertension. Methods A total of 216 elderly patients with mild to moderate essential hypertension were enrolled and treated by hydrochlorothiazide as the basic therapy for two weeks. Then the patients were randomly divided into four groups. Namely, the intensified antihypertensive and lipid lowering therapy group (hydrochlorothiazide 25 mg/d, Candesartan 8 mg/d, Rosuvastatin 10 mg/d, n=54), the intensified antihypertensive treatment group (hydrochlorothiazide 25 mg/d, Candesartan 8 mg/d, n=54), the antihypertensive and lipid lowering therapy group (hydrochlorothiazide 25 mg/d, Rosuvastatin 10 mg/d, n=54), and the control group (hydrochlorothiazide 25 mg/d, n=54). After 12-month treatment, the blood pressure, blood lipid and carotid-radial pulse wave velocity (crPWV) of each group were recorded. Results Twelve months

  1. The effect of lowering salt intake on ambulatory blood pressure to reduce cardiovascular risk in chronic kidney disease (LowSALT CKD study: protocol of a randomized trial

    Directory of Open Access Journals (Sweden)

    McMahon Emma J

    2012-10-01

    Full Text Available Abstract Background Despite evidence implicating dietary sodium in the pathogenesis of cardiovascular disease (CVD in chronic kidney disease (CKD, quality intervention trials in CKD patients are lacking. This study aims to investigate the effect of reducing sodium intake on blood pressure, risk factors for progression of CKD and other cardiovascular risk factors in CKD. Methods/design The LowSALT CKD study is a six week randomized-crossover trial assessing the effect of a moderate (180 mmol/day compared with a low (60 mmol/day sodium intake on cardiovascular risk factors and risk factors for kidney function decline in mild-moderate CKD (stage III-IV. The primary outcome of interest is 24-hour ambulatory blood pressure, with secondary outcomes including arterial stiffness (pulse wave velocity, proteinuria and fluid status. The randomized crossover trial (Phase 1 is supported by an ancillary trial (Phase 2 of longitudinal-observational design to assess the longer term effectiveness of sodium restriction. Phase 2 will continue measurement of outcomes as per Phase 1, with the addition of patient-centered outcomes, such as dietary adherence to sodium restriction (degree of adherence and barriers/enablers, quality of life and taste assessment. Discussion The LowSALT CKD study is an investigator-initiated study specifically designed to assess the proof-of-concept and efficacy of sodium restriction in patients with established CKD. Phase 2 will assess the longer term effectiveness of sodium restriction in the same participants, enhancing the translation of Phase 1 results into practice. This trial will provide much-needed insight into sodium restriction as a treatment option to reduce risk of CVD and CKD progression in CKD patients. Trial registration Universal Trial Number: U1111-1125-2149. Australian New Zealand Clinical Trials Registry Number: ACTRN12611001097932

  2. Distribution of peripheral arterial stiffness and endothelial function as well as their correlations with cardiovascular risk factors in children and adolescents%儿童青少年外周动脉顺应性、血管内皮功能的年龄变化规律及与心血管疾病危险因素的关系

    Institute of Scientific and Technical Information of China (English)

    穆锴; 张羿; 牛大彦; 叶莹; 严卫丽

    2016-01-01

    Objective To investigate the distribution of peripheral arterial stiffness,endothelial function and their correlations with cardiovascular risk factors in the 7-17 year-olds.Methods Normal weight and obese subjects aged 7-17 years with completed data on questionnaires,anthropometric and blood biochemical tests,were recruited from a cross-sectional population-based study on childhood hypertension in Minhang district of Shanghai.Automatic waveform analyzer (BP-203RPE-I) and Endopat 2000 were used to measure the arterial stiffness.Endothelial function with brachial-ankle pulse wave velocity (baPWV) and reactive hyperemia index (RHI) were recorded.BaPWV and RHI were standardized by age.Skewed biochemical variables were log transformed.Linear correlation analysis was performed to observe association between baPWV,RHI and other measured variables.Results A total of 452 normal-weight and 94 obese subjects were recruited,including 299 males.Data showed that baPWV and RHI increased with age in normal weight subjects (r=0.33,P<0.01;r=0.36,P<0.01).Results from Linear correlation analysis revealed that baPWV was positively correlated with BMI (r=0.13,P=0.002),systolic blood pressure (SBP) (r=0.20,P<0.01),diastolic blood pressure (DBP) (r=0.27,P<0.01),triglycerides (TG) (r=0.11,P=0.010),insulin (r=0.21,P=0.004) and the HOMA insulin resistance index (r=0.21,P=0.005),but negatively correlated with high-density lipoprotein cholesterol (r=-0.09,P=0.039).RH1 was positively correlated with BMI (r=0.10,P=0.018) but negatively correlated with DBP (r=-0.10,P=0.016).Males had higher baPWVs than females (P=0.04).However,RHI did not differ between genders.Conclusions The fact that baPWV and RHI increased along with age,indicated that the arterial stiffness and endothelial function continued to develop in normal weight childhood and adolescence.Arterial stiffness was correlated with cardiovascular risk-related parameters whereas endothelial function was not.BaPWV might be more

  3. Analysis on relationship between stiffness of large artery and variability of blood pressure in patients with chronic kidney disease without dialysis%非透析慢性肾脏病合并血压变异患者大动脉僵硬度分析

    Institute of Scientific and Technical Information of China (English)

    陈灿

    2015-01-01

    目的:探讨非透析慢性肾脏病(CKD)患者血压变异性与大动脉僵硬度的关系。方法选取2010年4月至2014年4月诊断为 CKD 3~5期非透析患者,检测24 h 动态血压,根据患者是否患有高血压以及血压变异性进行分组,分析各组各项指标的差异以及血压变异性与大动脉僵硬度的关系。结果共收集 CKD 合并高血压患者368例, CKD 血压正常患者64例。直线相关分析发现 CKD 合并高血压患者血压变异性与脉搏波传导速度(PWV)呈显著的负相关( r =-0.583,P ﹤0.05)。CKD 血压正常患者血压变异性与 PWV 呈显著的负相关( r =-0.844,P ﹤0.05)。多元线性回归分析患者各项观察指标与患者 PWV 的关系发现,CKD 合并高血压患者收缩压、舒张压、脉压、血压变异性、CKD 分期与患者 PWV 显著相关;CKD 血压正常患者血压变异性和 CKD 分期与患者 PWV 显著相关。结论 CKD 患者是否合并高血压,其血压的昼夜异常变化与患者大动脉僵硬度关系密切。%Objective To explore the relationship between variability of blood pressure and stiffness of large artery in patients with chronic kidney disease(CKD)without dialysis. Methods Patients with CKD at phase 3 ~ 5 without dialysis admitted in the department of internal medi-cine in this hospital during April 2010 to April 2014 were allocated in this study. Twenty four hours dynamic blood pressure had been examined, and patients were grouped according to whether they suffered from high blood pressure and variability of blood pressure. The difference in each in-dex of each group and the relationship between variability of blood pressure and stiffness of large artery had been analyzed. Results There were 368 patients with CKD and hypertension and 64 patients with CKD were allocated for this study. There was significant negative correlation between variability of blood pressure and PWV in patients with CKD and

  4. Advances in ambulatory monitoring: regulatory considerations.

    Science.gov (United States)

    Buckles, David; Aguel, Felipe; Brockman, Randall; Cheng, James; Demian, Cindy; Ho, Charles; Jensen, Donald; Mallis, Elias

    2004-01-01

    Conventional ambulatory electrocardiogram (ECG) (Holter) monitoring involves 2 or 3 surface leads recorded with electrode positions and signal characteristics that are different from diagnostic quality 12-lead ECGs due to the limitations imposed by technology on the ambulatory recorders. The rapid pace of technological development for medical devices, particularly electrocardiography, has now enabled the recording of diagnostic quality 12-lead ECG waveforms for extended time periods. This capability allows Holter recording to become another source for diagnostic 12-lead ECG records on a par with other modalities such as resting ECG and exercise stress testing. Additionally, other diagnostic techniques such as S-T segment analysis and Q-T interval analysis that rely on diagnostic quality waveforms can now be applied. All of these enhancements to the traditional Holter modality have altered the regulatory perspective of these devices, since the enhancements may represent a new intended use for the device.

  5. Cochlear implant in an ambulatory surgery center.

    Science.gov (United States)

    Joseph, Aimee M; Lassen, L Frederick

    2013-02-01

    Presbycusis, or sensorineural hearing loss in the elderly population, affects approximately 40% to 50% of people over the age of 75. A variety of devices are available to those with hearing loss. Cochlear implants, for example, are especially useful for those with severe-to-profound hearing loss. The population is aging, so the demand for cochlear implantation in ambulatory surgery centers will likely increase. Ambulatory surgery centers (ASC) can provide a more convenient and less expensive location for cochlear implant surgery than hospital-based operating facilities. Patient selection using standard ASC criteria, coupled with an understanding of the unique surgical and anesthetic needs of cochlear implant patients, are key to bringing this once exotic inpatient procedure into the ASC.

  6. Anticoagulation management in the ambulatory surgical setting.

    Science.gov (United States)

    Eisenstein, Diana Hill

    2012-04-01

    Many people receiving maintenance anticoagulation therapy require surgery each year in ambulatory surgery centers. National safety organizations focus attention toward improving anticoagulation management, and the American College of Chest Physicians has established guidelines for appropriate anticoagulation management to balance the risk of thromboembolism when warfarin is discontinued with the risk of bleeding when anticoagulation therapy is maintained. The guidelines recommend that patients at high or moderate risk for thromboembolism should be bridged with subcutaneous low-molecular-weight heparin or IV unfractionated heparin with the interruption of warfarin, and low-risk patients may require subcutaneous low-molecular-weight heparin or no bridging with the interruption of warfarin. The guidelines recommend the continuation of warfarin for patients who are undergoing minor dermatologic or dental procedures or cataract removal. The literature reveals, however, that there is not adequate adherence to these recommendations and guidelines. Management of anticoagulation therapy by a nurse practitioner may improve compliance and safety in ambulatory surgery centers.

  7. Stiffness after total knee arthroplasty.

    Science.gov (United States)

    Manrique, Jorge; Gomez, Miguel M; Parvizi, Javad

    2015-04-01

    Stiffness after total knee arthroplasty (TKA) adversely affects outcome and impacts patient function. Various risk factors for stiffness after TKA have been identified, including reduced preoperative knee range of motion, history of prior knee surgery, etiology of arthritis, incorrect positioning or oversizing of components, and incorrect gap balancing. Mechanical and associated causes, such as infection, arthrofibrosis, complex regional pain syndrome, and heterotopic ossification, secondary gain issues have also been identified. Management of stiffness following TKA can be challenging. The condition needs to be assessed and treated in a staged manner. A nonsurgical approach is the first step. Manipulation under anesthesia may be considered within the first 3 months after the index TKA, if physical therapy fails to improve the range of motion. Beyond this point, consideration should be given to surgical intervention such as lysis of adhesions, either arthroscopically or by open arthrotomy. If the cause of stiffness is deemed to be surgical error, such as component malpositioning, revision arthroplasty is indicated. The purpose of this article is to evaluate the various aspects of management of stiffness after TKA.

  8. Ambulatory Assessment of Depression in Primary Care

    Science.gov (United States)

    2016-06-29

    Statement The auth~r hereby certifies that the use of any copyrighted material in the thesis manuscript entitled: "AMBULATORY ASSESSMENT OF DEPRESSION IN...Department Medical and Clinical Psychology Uniformed Services University of the Health Sciences 11 iii Abstract Depression is common among individuals in...primary care. Despite the prevalence of depression in primary care, patients are usually not adequately treated for depression . Often the treatment

  9. Ambulatory Blood Pressure Monitoring in the Elderly

    OpenAIRE

    Juan Diego Mediavilla García; Fernando Jaén Águila; Celia Fernández Torres; Blas Gil Extremera; Juan Jiménez Alonso

    2012-01-01

    The incidence of hypertension is high in the elderly and is present in 2/3 of the patients older than 65 years. Prevalence can reach 90% in patients older than 80 years. The presence of isolated systolic hypertension (ISH) is characteristic of this population. However, the prevalence of hypertension by ambulatory blood pressure monitoring (ABPM) is not well known. In this study, we analyzed the special characteristics of hypertension in this population, giving special emphasis on ABPM readings.

  10. The evolution of ambulatory ECG monitoring.

    Science.gov (United States)

    Kennedy, Harold L

    2013-01-01

    Ambulatory Holter electrocardiographic (ECG) monitoring has undergone continuous technological evolution since its invention and development in the 1950s era. With commercial introduction in 1963, there has been an evolution of Holter recorders from 1 channel to 12 channel recorders with increasingly smaller storage media, and there has evolved Holter analysis systems employing increasingly technologically advanced electronics providing a myriad of data displays. This evolution of smaller physical instruments with increasing technological capacity has characterized the development of electronics over the past 50 years. Currently the technology has been focused upon the conventional continuous 24 to 48 hour ambulatory ECG examination, and conventional extended ambulatory monitoring strategies for infrequent to rare arrhythmic events. However, the emergence of the Internet, Wi-Fi, cellular networks, and broad-band transmission has positioned these modalities at the doorway of the digital world. This has led to an adoption of more cost-effective strategies to these conventional methods of performing the examination. As a result, the emergence of the mobile smartphone coupled with this digital capacity is leading to the recent development of Holter smartphone applications. The potential of point-of-care applications utilizing the Holter smartphone and a vast array of new non-invasive sensors is evident in the not too distant future. The Holter smartphone is anticipated to contribute significantly in the future to the field of global health.

  11. Effective analgesic modalities for ambulatory patients.

    Science.gov (United States)

    Redmond, Martin; Florence, Barry; Glass, Peter S A

    2003-06-01

    The introduction of government-mandated standards for pain management has focused our attention on postoperative pain. With the recent JACHO standards' for ambulatory surgery, it is imperative that all health care workers who care for these patients are familiar with appropriate pain management. Developments in our understanding of the pathophysiology of acute pain have further enhanced our ability to improve pain management for postoperative ambulatory patients. This has led to the concept of preventive analgesia (inhibition of physiological and pathological secondary inflammatory pain). Extensive work has shown that this is best achieved using a multimodel approach usually consisting of an NSAID, opioid, and local anesthetic. NMDA antagonists (ketamine, dextromethorphan) and alpha-2 agnoists (clonodine) show potential supplements to further enhance pain management, especially if given preemptively. Nonpharmacological intervention such as cold therapy or acupuncture may also be considered. The armanentarium for effective pain management has improved substantially over the past few years. The challenge is for health care workers to implement these therapies to obtain optimum pain management in ambulatory surgical patients.

  12. 45. Ezetimibe and statins yields on silent holter ambulatory myocardial ischemia

    Directory of Open Access Journals (Sweden)

    W. Kadro

    2016-07-01

    Full Text Available Further cholestrol lowering may affect silent ischemia detected on holter monitoring. Cholesterol lowering is associated with a reduction in cardiovascular morbidity and mortality. Statins are the main drugs for cholesterol lowering. Ezetimibe when added to statins gives further reduction in cholesterol but its long-term effect on cardiovascular morbidity and mortality and ischemic events is not known. This study sought to determine whether further cholesterol lowering with ezitimibe will also results in a reduction of myocardial ischemia during daily life. We enrolled 50 patients with proven stable coronary artery disease (CAD and at least one episode of ST-segment depression on ambulatory ECG monitoring. All of them were receiving optimal therapy for CAD including statin therapy for cholesterol reduction. 25 patients were randomized to continue their statin therapy (Statin only group and 25 to recieve statin plus ezitimibe 10 mg/day (ezitimibe group. Serum cholesterol and LDL cholesterol levels and ambulatory monitoring were repeated after 4–6 months of therapy. The two groups were comparable with respect to baseline characteristics, number of episodes of ST-segment depression, and baseline serum cholesterol levels. The ezitimibe group had lower mean total and LDL cholesterol levels at study end and experienced a significant reduction in the number of episodes of ST-segment depression compared with the statin only group. ST-segment depression was completely resolved in 13 of 25 patients (52% in the ezitimibe group versus 3 of 25 (12% in the statin only group. The ezitimibe group exhibited a highly significant reduction in ambulatory ischemia (P < .001. By logistic regression, treatment with ezitimibe was an independent predictor of ischemia resolution. Further cholesterol lowering with ezitimibe can result in reduction or resolution of myocardial ischemia recorded as episodes of ST-segment depression in ambulatory monitoring of the ECG.

  13. [25 years of organized ambulatory heart sport in Luxembourg. The development of a sustained rehabilitation model].

    Science.gov (United States)

    Delagardelle, Charles; Feiereisen, Patrick

    2011-01-01

    After Second World War cardiovascular disease (CVD), especially coronary artery disease (CAD), turned out to be an epidemic in the western countries including the Grand-Duchy of Luxembourg, and accounted for nearly half of all deaths. A lot of strategies, among them treatment by physical activity, were developed to fight this challenge and, fortunately, a mortality regression of about 50 % could be achieved. Nowadays, eastern European countries and, more recently, China and India face an increasing CVD mortality. During the seventies ambulatory heart sport clubs, then labeled as, "coronary clubs" became very popular in Europe especially in West-Germany. Around 2000 there were more than 6000 heart sports groups in Germany. In 1984 a first group was founded in Luxembourg City (Centre) a, 1991 a second group started in Esch/Alzette (South) and in 2002 a third regional group in Ettelbruck (North) so that, by now, the 3 main public health districts of the Grand-Duchy of Luxembourg can offer regular ambulatory sports activities to almost all concerned cardiac patients in the country. The ambulatory heart sport groups of Luxembourg cooperate in a federated association allowing an integrated logistic organization. Since the beginning nineties cardiac rehabilitation became a field of interest to the university faculties and later of scientific societies, like the American Heart Association (AHA) and the European Society of Cardiology (ESC). New subgroups were founded and guidelines were published and renewed. The movement of ambulatory heart sport groups was more or less neglected in the prevention and rehabilitation activities of the scientific societies. Recently the ESC proposed a new definition of comprehensive CVD prevention and rehabilitation programmes as "coordinated, multifaceted interventions designed to optimize a cardiac patient's physical, psychological, and social functioning, in addition to stabilizing, slowing, or even reversing the progression of the

  14. Ambulatory Blood Pressure Monitoring in Clinical Practice: A Review

    OpenAIRE

    Turner, J. Rick; Viera, Anthony J.; Shimbo, Daichi

    2014-01-01

    Ambulatory blood pressure monitoring offers the ability to collect blood pressure readings several times an hour across a 24-hour period. Ambulatory blood pressure monitoring facilitates the identification of white-coat hypertension, the phenomenon whereby certain individuals who are not on antihypertensive medication show elevated blood pressure in a clinical setting but show non-elevated blood pressure averages when assessed by ambulatory blood pressure monitoring. Additionally, readings ca...

  15. Ambulatory anesthesia: optimal perioperative management of the diabetic patient

    OpenAIRE

    Polderman JAW; van Wilpe R; Eshuis JH; Preckel B; Hermanides J

    2016-01-01

    Jorinde AW Polderman, Robert van Wilpe, Jan H Eshuis, Benedikt Preckel, Jeroen Hermanides Department of Anaesthesiology, Academic Medical Centre, University of Amsterdam, Amsterdam, the Netherlands Abstract: Given the growing number of patients with diabetes mellitus (DM) and the growing number of surgical procedures performed in an ambulatory setting, DM is one of the most encountered comorbidities in patients undergoing ambulatory surgery. Perioperative management of ambulatory patients wi...

  16. Lase Ultrasonic Web Stiffness tester

    Energy Technology Data Exchange (ETDEWEB)

    Tim Patterson, Ph.D., IPST at Ga Tech

    2009-01-12

    The objective is to provide a sensor that uses non-contact, laser ultrasonics to measure the stiffness of paper during the manufacturing process. This will allow the manufacturer to adjust the production process in real time, increase filler content, modify fiber refining and as result produce a quality product using less energy. The sensor operates by moving back and forth across the paper web, at pre-selected locations firing a laser at the sheet, measuring the out-of-plane velocity of the sheet then using that measurement to calculate sheet stiffness.

  17. Acupuncture in ambulatory anesthesia: a review

    Directory of Open Access Journals (Sweden)

    Norheim AJ

    2015-09-01

    Full Text Available Arne Johan Norheim,1 Ingrid Liodden,1 Terje Alræk1,2 1National Research Center in Complementary and Alternative Medicine (NAFKAM, Department of Community Medicine, Faculty of Health Sciences, University of Tromsø – The Arctic University of Norway, Tromsø, 2The Norwegian School of Health Sciences, Institute of Acupuncture, Kristiania University College, Oslo, NorwayBackground: Post-anesthetic morbidities remain challenging in our daily practice of anesthesia. Meta-analyses and reviews of acupuncture and related techniques for postoperative nausea and vomiting (POVN and postoperative vomiting (POV show promising results while many clinicians remain skeptical of the value of acupuncture. Given the interest in finding safe non-pharmacological approaches toward postoperative care, this body of knowledge needs to be considered. This review critically appraises and summarizes the research on acupuncture and acupressure in ambulatory anesthesia during the last 15 years.Methods: Articles were identified through searches of Medline, PubMed, and Embase using the search terms “acupuncture” or “acupuncture therapy” in combination with “ambulatory anesthesia” or “ambulatory surgery” or “day surgery” or “postoperative”. A corresponding search was done using “acupressure” and “wristbands”. The searches generated a total of 104, 118, and 122 references, respectively.Results: Sixteen studies were included; eight studies reported on acupuncture and eight on acupressure. Nine studies found acupuncture or acupressure effective on primary endpoints including postoperative nausea and vomiting, postoperative pain, sore throat, and emergence agitation. Four studies found acupuncture had a similar effect to antiemetic medication.Conclusion: Overall, the studies were of fairly good quality. A large proportion of the reviewed papers highlights an effect of acupuncture or acupressure on postoperative morbidities in an ambulatory setting

  18. Ambulatory anesthesia: optimal perioperative management of the diabetic patient

    Directory of Open Access Journals (Sweden)

    Polderman JAW

    2016-05-01

    Full Text Available Jorinde AW Polderman, Robert van Wilpe, Jan H Eshuis, Benedikt Preckel, Jeroen Hermanides Department of Anaesthesiology, Academic Medical Centre, University of Amsterdam, Amsterdam, the Netherlands Abstract: Given the growing number of patients with diabetes mellitus (DM and the growing number of surgical procedures performed in an ambulatory setting, DM is one of the most encountered comorbidities in patients undergoing ambulatory surgery. Perioperative management of ambulatory patients with DM requires a different approach than patients undergoing major surgery, as procedures are shorter and the stress response caused by surgery is minimal. However, DM is a risk factor for postoperative complications in ambulatory surgery, so should be managed carefully. Given the limited time ambulatory patients spend in the hospital, improvement in management has to be gained from the preanesthetic assessment. The purpose of this review is to summarize current literature regarding the anesthesiologic management of patients with DM in the ambulatory setting. We will discuss the risks of perioperative hyperglycemia together with the pre-, intra-, and postoperative considerations for these patients when encountered in an ambulatory setting. Furthermore, we provide recommendations for the optimal perioperative management of the diabetic patient undergoing ambulatory surgery. Keywords: diabetes mellitus, perioperative period, ambulatory surgery, insulin, complications, GLP-1 agonist, DPP-4 inhibitor

  19. Prognostic value of aortic stiffness and calcification for cardiovascular events and mortality in dialysis patients: outcome of the calcification outcome in renal disease (CORD) study

    DEFF Research Database (Denmark)

    Verbeke, Francis; Van Biesen, Wim; Honkanen, Eero;

    2011-01-01

    BACKGROUND AND OBJECTIVES: Radiographic calcification and arterial stiffness each individually are predictive of outcome in dialysis patients. However, it is unknown whether combined assessment of these intermediate endpoints also provides additional predictive value. DESIGN, SETTING, PARTICIPANT...

  20. 代谢综合征患者可溶性晚期糖基化终产物受体与动脉僵硬度的关系%Correlation between soluble receptor for advanced glycation endproducts and arterial stiffness in patients with metabolic syndrome

    Institute of Scientific and Technical Information of China (English)

    田朝伟; 王丽; 晋荣; 钟赟; 刘世明

    2015-01-01

    Objective investigate the correlation between plasma soluble receptor for advanced glycation endproducts (sRAGE) and arterial stiffness in patients with different types of metabolic syndrome (MS).Methods A total of 180 subjects were drawn from a epidemiologic follow-up study,including 60 cases non-metabolic syndrome (NMS),60 cases metabolic syndrome without diabetes mellitus (NDMMS),60 cases metabolic syndrome with diabetes mellitus (DMMS).Carotid femoral arterial pulse wave velocity (CFPWV) was assessed by the French KangPuLe atherosclerosis measurement instrument,and plasma sRAGE levels were measured by ELISA.Comparison of mean in multiple groups was conducted by analysis of variance.Multivariate analysis was done with multiple linear stepwise regression analysis.P < 0.05 was considered as statistically significant difference.Results Compared with NMS group,plasma sRAGE levels were significantly lower in DMMS and NDMMS groups [(635.07 ± 229.20) pg/mL vs.(671.17 ± 358.16) pg/mL vs.(992.99 ± 427.83) pg/mL,P =0.001].CFPWV of DMMS group was significantly higher than that of NMDMS and NMS groups (14.22 ±3.14) m/s vs.(12.15 ±2.79) m/s vs.(11.66 ± 2.52) m/s,P =0.002).Plasma sRAGE level was negatively correlated with CFPWV (r =-0.278,P =0.005).(3) Multiple linear regression analysis demonstrated that age (β =-0.091,95% CI-0.096 ~-0.095,P =0.031),HDL-C (β =1.295,95% CI 1.231 ~ 1.360,P =0.022) and sRAGE (β =0.119,95% CI 0.118 ~ 0.130,P =0.032) had a significant effect on CFPWV.Conclusions The increased arterial stiffness is closely related to the discreased plasma sRAGE levels in MS.Plasma sRAGE maybe a novel target for vascular disease prevention and treatment in patients with metabolic syndrome.%目的 探讨在不同类型代谢综合征(metabolic syndrome,MS)患者血浆中可溶性晚期糖基化终产物受体(soluble receptor for advanced glycation endproducts,sRAGE)与动脉僵硬度的关系.方法 采用病例对照的方

  1. Renal disease in pregnancy ambulatory issues.

    Science.gov (United States)

    Phelan, Sharon T

    2012-09-01

    Acute and chronic renal disease will complicate prenatal care. Normal physiological changes during pregnancy make the urinary tract system more vulnerable to infectious complications or worsening of preexisting disease. Much of the focus of prenatal care includes screening for these concerns both at the onset of prenatal care and through the pregnancy and postpartum course. With careful and attentive care, the pregnancy outcome for women with significant renal disease has improved and the occurrence of renal injury or obstetric complications due to infectious insults has decreased. This manuscript reviews the current ambulatory prenatal care as it relates to the urinary tract in pregnancy.

  2. [Hospitalisations for ambulatory care sensitive conditions in Germany

    NARCIS (Netherlands)

    Freund, T.; Heller, G.; Szecsenyi, J.

    2014-01-01

    BACKGROUND: On the basis of the assumption that a significant proportion of hospitalisations for so-called ambulatory care sensitive conditions (ACSCs) are potentially avoidable by ambulatory care measures, hospitalisation rates for ACSCs are used internationally as population based indicators for a

  3. An Ambulatory Program for Surgical Residents and Medical Students.

    Science.gov (United States)

    Levy, Margaret

    1988-01-01

    A pilot program based in a freestanding ambulatory surgery center at the Chicago Medical School Department of Surgery is described, its curriculum outlined, and the daily activities of the residents and medical students are detailed. A brief history of ambulatory surgery is given. (Author/MLW)

  4. Exercise Helps Ease Arthritis Pain and Stiffness

    Science.gov (United States)

    ... pain, and helps combat fatigue. Of course, when stiff and painful joints are already bogging you down, ... can make your joints even more painful and stiff. That's because keeping your muscles and surrounding tissue ...

  5. Explicit Time-Stepping for Stiff ODEs

    CERN Document Server

    Eriksson, Kenneth; Logg, Anders; 10.1137/S1064827502409626

    2012-01-01

    We present a new strategy for solving stiff ODEs with explicit methods. By adaptively taking a small number of stabilizing small explicit time steps when necessary, a stiff ODE system can be stabilized enough to allow for time steps much larger than what is indicated by classical stability analysis. For many stiff problems the cost of the stabilizing small time steps is small, so the improvement is large. We illustrate the technique on a number of well-known stiff test problems.

  6. Energy-Efficient Variable Stiffness Actuators

    NARCIS (Netherlands)

    Visser, Ludo C.; Carloni, Raffaella; Stramigioli, Stefano

    2011-01-01

    Variable stiffness actuators are a particular class of actuators that is characterized by the property that the apparent output stiffness can be changed independent of the output position. To achieve this, variable stiffness actuators consist of a number of elastic elements and a number of actuated

  7. Shoulder Stiffness : Current Concepts and Concerns

    NARCIS (Netherlands)

    Itoi, Eiji; Arce, Guillermo; Bain, Gregory I.; Diercks, Ronald L.; Guttmann, Dan; Imhoff, Andreas B.; Mazzocca, Augustus D.; Sugaya, Hiroyuki; Yoo, Yon-Sik

    2016-01-01

    Shoulder stiffness can be caused by various etiologies such as immobilization, trauma, or surgical interventions. The Upper Extremity Committee of ISAKOS defined the term "frozen shoulder" as idiopathic stiff shoulder, that is, without a known cause. Secondary stiff shoulder is a term that should be

  8. 76 FR 6572 - Non-Ambulatory Disabled Veal Calves and Other Non-Ambulatory Disabled Livestock at Slaughter...

    Science.gov (United States)

    2011-02-07

    ... inspection regulations to prohibit the slaughter of non-ambulatory disabled pigs, sheep, goats, and other... the mother's colostrum, iron deficient diets, intensive confinement, and lack of activity, result in... to require that non- ambulatory disabled pigs, sheep, goats, and other amenable livestock species...

  9. Association between non-alcoholic fatty liver disease and arterial stiffness in the non-obese, non-hypertensive, and non-diabetic young and middle-aged Chinese population%非肥胖、高血压和糖尿病的中国中青年人群中非酒精性脂肪性肝病和动脉硬度的关系研究

    Institute of Scientific and Technical Information of China (English)

    Xin-yan YU; Yi ZHAO; Xiao-xiao SONG; Zhen-ya SONG

    2014-01-01

    研究目的:探讨在非肥胖、高血压和糖尿病的中国中青年群人中非酒精性脂肪性肝病(NAFLD)和动脉硬度的关系。  创新要点:在非肥胖、高血压和糖尿病的中青年人群中,阐明NAFLD和动脉硬度的关系,对预防和诊断早期动脉硬度有重要临床意义。  研究方法:在非肥胖、高血压和糖尿病的中青年体检人群中进行一项大型横断面研究。用B超诊断脂肪肝,用臂踝脉搏波指数(baPWV)测量动脉硬度,根据是否有NAFLD和baPWV水平分组。  重要结论:NAFLD 组患者的 baPWV 水平明显高于对照组((1321±158) cm/s vs.(1244±154) cm/s;P<0.001),NAFLD患病率在 baPWV升高组明显高于 baPWV正常组(29.3% vs.16.9%;P<0.001),且NAFLD患病率随baPWV水平和动脉硬度程度的升高而升高(两者趋势P值<0.001)。多因素线性回归分析表明,NAFLD发生与baPWV独立相关。因此,在非肥胖、高血压和糖尿病的中国中青年群人中,NAFLD发生与动脉硬度密切相关。%Background and objective:Non-alcoholic fatty liver disease (NAFLD) is associated with arterial stiffness in the general population. Age, obesity, hypertension, and diabetics are risk factors for arterial stiffness. In this study, we aimed to investigate the association between NAFLD and arterial stiffness as measured by brachial-ankle pulse wave velocity (baPWV) in the non-obese, non-hypertensive, and non-diabetic young and middle-aged Chinese population. Methods:A cross-sectional study with 1296 non-obese, non-hypertensive, and non-diabetic young and middle-aged (20-65 years) subjects undergoing routine medical check-ups in the International Health Care Center of the Second Affiliated Hospital of School of Medicine of Zhejiang University was carried out. Fatty liver was diagnosed by ultra-sonography, and baPWV was measured using an automatic waveform analyzer. The subjects were classified into two groups

  10. Ambulatory blood pressure values in healthy children

    Directory of Open Access Journals (Sweden)

    Paripović Dušan

    2006-01-01

    Full Text Available Ambulatory blood pressure monitoring (ABPM is an important tool in the diagnosis and management of childhood hypertension. Normal ambulatory blood pressure (ABP values in children with body heights between 100 and 120 cm have not been reported. The aim of the study was to establish the normal range of values for ABPM in these children. 24-hour ABPM was performed in 40 normotensive (auscultatory casual blood pressure was obtained before ABPM subjects, aged from 4 to 6 years (26 males, 14 females with body heights between 95 and 125 cm. ABPM was carried out on non-dominant arm using the oscillometric device (SpaceLab 90207 with appropriate cuff size. The monitor was programmed to measure BP every 15 min. during the day (6 a.m. to 10 p.m. and every 30 min. during the night (10 p.m. to 6 a.m.. The mean daytime SBP/DBP in boys and girls was 108+/-6/67+/-5 and 105+/-5/66+/-1, respectively. The mean nighttime SBP/DBP in boys and girls was 98+/-6/56+/-5 and 97+/-7/56+/-4, respectively. There was a significant difference between day and night readings of SBP, DBP and heart rate (nocturnal fall was observed. The distribution of ABP noted in this study could serve as preliminary reference. A multicenter study should be performed to provide normal ranges of ABP.

  11. Negative stiffness in gear contact

    Directory of Open Access Journals (Sweden)

    Půst L.

    2015-12-01

    Full Text Available The tooth contact stiffness is very often included in dynamic mathematical models of gear drives. It is an important value for calculation of torsion eigenfrequencies as well as the dynamic properties of the whole transmission systems. Planetary gear drives have several advantages over simple parallel axis gears, especially due to theirs compact design and great torque-to-weight ratio caused by multiple parallel paths. However, the dimensional or mounting errors can cause that some planets have the tendency to take more load than the others. One of the ways how to improve load sharing is the application of flexible planetary pins or by using a free central wheel. However in such cases, the wheels motion is defined in one rotation coordinate and two translation coordinates — tangential and radial. The reaction force at radial change of axis distance is usually neglected. The focus of this contribution is to derive the stiffness of this radial connection and to analyse the influence of radial stiffness on planetary gear dynamics.

  12. Analysis of Arterial Mechanics During Head-Down-Tilt Bed Rest

    Science.gov (United States)

    Elliott, Morgan B.; Martin, David S.; Westby, Christian M.; Stenger, Michael B.; Platts, Steven H.

    2014-01-01

    Carotid, brachial, and tibial arteries reacted differently to HDTBR. Previous studies have not analyzed the mechanical properties of the human brachial or anterior tibial arteries. After slight variations during bed-rest, arterial mechanical properties and IMT returned to pre-bed rest values, with the exception of tibial stiffness and PSE, which continued to be reduced post-bed rest while the DC remained elevated. The tibial artery remodeling was probably due to decreased pressure and volume. Resulting implications for longer duration spaceflight are unclear. Arterial health may be affected by microgravity, as shown by increased thoracic aorta stiffness in other ground based simulations (Aubert).

  13. Predictors of exercise participation in ambulatory and non-ambulatory older people with multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Michelle Ploughman

    2015-08-01

    Full Text Available Background. Exercise at moderate intensity may confer neuroprotective benefits in multiple sclerosis (MS, however it has been reported that people with MS (PwMS exercise less than national guideline recommendations. We aimed to determine predictors of moderate to vigorous exercise among a sample of older Canadians with MS who were divided into ambulatory (less disabled and non-ambulatory (more disabled groups.Methods. We analysed data collected as part of a national survey of health, lifestyle and aging with MS. Participants (n = 743 were Canadians over 55 years of age with MS for 20 or more years. We identified ‘a priori’ variables (demographic, personal, socioeconomic, physical health, exercise history and health care support that may predict exercise at moderate to vigorous intensity (>6.75 metabolic equivalent hours/week. Predictive variables were entered into stepwise logistic regression until best fit was achieved.Results. There was no difference in explanatory models between ambulatory and non-ambulatory groups. The model predicting exercise included the ability to walk independently (OR 1.90, 95% CI [1.24–2.91]; low disability (OR 1.50, 95% CI [1.34–1.68] for each 10 point difference in Barthel Index score, perseverance (OR 1.17, 95% CI [1.08–1.26] for each additional point on the scale of 0–14, less fatigue (OR 2.01, 95% CI [1.32–3.07] for those in the lowest quartile, fewer years since MS diagnosis (OR 1.58, 95% CI [1.11–2.23] below the median of 23 years and fewer cardiovascular comorbidities (OR 1.55 95% CI [1.02–2.35] one or no comorbidities. It was also notable that the factors, age, gender, social support, health care support and financial status were not predictive of exercise.Conclusions. This is the first examination of exercise and exercise predictors among older, more disabled PwMS. Disability is a major predictor of exercise participation (at moderate to vigorous levels in both ambulatory and non-ambulatory

  14. Reference values of one-point carotid stiffness parameters determined by carotid echo-tracking and brachial pulse pressure in a large population of healthy subjects.

    Science.gov (United States)

    Vriz, Olga; Aboyans, Victor; Minisini, Rosalba; Magne, Julien; Bertin, Nicole; Pirisi, Mario; Bossone, Eduardo

    2017-03-02

    Arterial stiffness can predict cardiovascular events, and the aim of this study was to produce age- and sex-specific reference values for echo-tracking carotid stiffness in healthy subjects. A total of 900 subjects (500 males, mean age 45.8±19 years) were enrolled. Common carotid artery stiffness and compliance, using a high-definition echo-tracking ultrasound system, were evaluated. To compare stiffness parameters across the different age groups, individual scores were transformed into T-scores, indicating how many standard deviation (s.d.) units an individual's score was above or below the mean that was observed in the group including same-sex individuals aged 36 to 44 years. Carotid stiffness was similar among genders, except compliance, which was lower in women (Pgroups. Stiffness parameters increased significantly with age, but the opposite occurred for compliance. The T-score was found to increase significantly across all age groups, with a steeper increase in stiffness around the age of 60 years in women. For each T-score s.d., the corresponding carotid absolute values for arterial stiffness and compliance were obtained. In a multivariate model, carotid stiffness parameters were constantly and independently associated with age, mean arterial pressure, pulse pressure, heart rate and body mass index. Our study provides a normogram of carotid arterial stiffness and compliance indices obtained with the echo-tracking method in a large population of healthy subjects stratified by gender and age that can be used in clinical practice.Hypertension Research advance online publication, 2 March 2017; doi:10.1038/hr.2017.24.

  15. Indices of vascular stiffness and wave reflection in relation to body mass index or body fat in healthy subjects.

    Science.gov (United States)

    Wykretowicz, Andrzej; Adamska, Karolina; Guzik, Przemyslaw; Krauze, Tomasz; Wysocki, Henryk

    2007-10-01

    1. Obesity appears to influence vascular stiffness, an important cardiovascular risk factor. An accurate picture of arterial stiffness may be obtained when a combination of various techniques is used. 2. The purpose of the present study was to assess whether the body mass index (BMI) and body fat content obtained by bioimpedance were of equal value in estimating the influence of body fatness on various indices of vascular stiffness and wave reflection. 3. A total of 175 healthy subjects was studied. Anthropometric measurements and total body bio-impedance analysis were performed to assess fat mass as a proportion of total body composition. Arterial stiffness and wave reflection were assessed using digital volume pulse analysis and tonometric measurement of the wave reflection indices and central haemodynamics. 4. Significant differences in the stiffness index (SI(DVP); P < 0.0001), peripheral augmentation index (pAI(x); P < 0.0001), central augmentation index (cAI(x); P < 0.0001), peripheral pulse pressure (pPP; P = 0.026) and central pulse pressure (cPP; P < 0.0001) were found when the population examined was divided accordingly to tertile of body fat content. However, subdividing various indices of arterial stiffness according to the tertile of BMI did not reveal any significant differences between groups, except for pPP and cPP. 5. Body fat content was significantly correlated with SI(DVP), pAI(x), cAI(x), pPP and cPP. The BMI correlated weakly with SI(DVP), pPP and cPP. 6. In conclusion, the BMI is not very useful in predicting changes in arterial stiffness and wave reflection due to obesity. However, stiffness and wave reflection indices derived from digital volume pulse analysis, the characteristics of radial and aortic pressure waveforms and peripheral and aortic pulse pressure are all related to body fat content, as estimated by bioimpedance.

  16. Measurement and Treatment of Passive Muscle Stiffness

    DEFF Research Database (Denmark)

    Kirk, Henrik

    This PhD thesis is based on research conducted at the University of Copenhagen and Helene Elsass Center from 2012 to 2015. Measurements and treatment of passive muscle stiffness in people with cerebral palsy (CP) comprise the focus of the thesis. The thesis summarizes the results from four studies...... stiffness. I introduce how to evaluate and distinguish between passive muscle stiffness and reflex-mediated stiffness in research and in clinical practice. Furthermore, I present ”the Portable Spasticity Assessment Device”, which was developed as a part of the PhD study. I discuss the validity......-mediated stiffness was considered a major problem. However, this study shows that significantly reduced RFD and increased passive muscle stiffness, rather than reflex-mediated stiffness, are the major contributors to impaired gait function in adults with CP, compared with neurologically healthy subjects. The third...

  17. Effects of environmental noise exposure on 24-h ambulatory vascular properties in adults.

    Science.gov (United States)

    Chang, Ta-Yuan; Liu, Chiu-Shong; Hsieh, Hsiu-Hui; Bao, Bo-Ying; Lai, Jim-Shoung

    2012-10-01

    Exposure to environmental noise has been associated with hypertension, but the related mechanism of vascular structural changes is unclear. This repeated-measure study investigated the effects of noise exposure on the 24-h ambulatory vascular structural properties in 66 adults aged 18-32 years. Individual noise exposure and personal vascular parameters were measured simultaneously in all subjects. Linear mixed-effects regressions were used to estimate the effects. A 1-A-weighted decibel (dBA) increase was significantly associated with the transient effects of 1.39 (95% confidence interval: 1.07, 1.79) %mL/mmHg in arterial compliance at nighttime but -1.70 (-2.05, -1.10) kdynes·s/cm(5) in arterial resistance during the daytime and -2.38 (-3.44, -1.64) kdynes·s/cm(5) in arterial resistance at nighttime among all subjects. Such effects were observed in arterial distensibility only during the daytime after the 30-min (-1.84 [-2.61, -1.29] %/mmHg) and 60-min (-2.06 [-2.95, -1.44] %/mmHg) time-lagged noise exposures. For 24-h environmental noise, a 1-dBA increment was significantly associated with a sustained increase of 1.25 (1.10, 1.42) %mL/mmHg in arterial compliance but a decrease of 2.12 (-2.51, -1.80) kdynes·s/cm(5) in arterial resistance. Environmental noise exposure may have transient and sustained effects on adult vascular properties.

  18. Computer database of ambulatory EEG signals.

    Science.gov (United States)

    Jayakar, P B; Brusse, E; Patrick, J P; Shwedyk, E; Seshia, S S

    1987-01-01

    The paper describes an ambulatory EEG database. The database contains segments of AEEGs done on 45 subjects. Each epoch (1/8th second or more) of AEEG data has been annotated into 1 of 40 classes. The classes represent background activity, paroxysmal patterns and artifacts. The majority of classes have over 200 discrete epochs. The structure is flexible enough to allow additional epochs to be readily added. The database is stored on transportable media such as digital magnetic tape or hard disk and is thus available to other researchers in the field. The database can be used to design, evaluate and compare EEG signal processing algorithms and pattern recognition systems. It can also serve as an educational medium in EEG laboratories.

  19. [Ambulatory ureteral lithotripsy with "Modulith SL-20"].

    Science.gov (United States)

    González Enguita, C; Calahorra Fernández, F J; García de la Peña, E; Rodríguez-Miñón Cifuentes, J L; Vela Navarrete, R

    1993-03-01

    Analysis of our experience in 'in situ' ambulatory shockwave extracorporeal lithofragmentation of ureteral stones in 104 patients seen in the Lithotrity Unit, Urology Service, Fundación "Jiménez Díaz". Using Modulith SL 20, a third generation lithotripter, 'in situ' disintegration was achieved in 82.69% of cases, 51.92% of which were fragmented in a single lithotrity session. As a first choice, no ureteral handling was used in any of the patients prior to lithotrity. In 9.62% of patients it was necessary to place a 'double J' by-pass catheter, due to the disease presenting with a septic picture. The patient's position was either dorsal or ventral decubitus depending on the lithiatic site, while location and focusing of the stones was done radiologically. All patients were treated ambulatory without hospitalization. Only 18% was given oral or i.v. anaesthesia. Fursemide 40 mg was administered to all patients shortly before starting the session. Each patient received an average of 3,200 shockwaves per session (14-18 Kv, average 16 Kv). Haematuria was the single and modest side effect that happened during the 24 hours following lithofragmentation in 30% of patients, while 20% reported slight discomfort at the time of eliminating the gritted stones. We conclude stating that 'in situ' shockwave extracorporeal lithotrity of ureteral stones with Modulith SL 20 allows for elective disintegration of ureteral stones in whatever location they are found, due to the patient's easy positioning. The simple location and focusing of ureteral stones has allowed us to treat and solve some cases of ureteral lithiasis at the precise moment of the nephritic colic painful emergency, thus speeding up and facilitating the resolution of the condition. Our results and our strategy imply a new change of direction in the management of these lithiasis, as opposed to the well established and historical doctrines in existence regarding stones with ureteral location.

  20. Estudo da demanda ambulatorial da clínica de odontologia da Universidade do Estado do Amazonas

    OpenAIRE

    Sponchiado Júnior,Emílio Carlos; Souza,Torricelly Barreto de

    2011-01-01

    O objetivo deste trabalho foi avaliar a demanda ambulatorial da Clínica de Odontologia da Universidade do Estado do Amazonas (UEA). Foram entrevistados cem pacientes em tratamento na disciplina de semiologia; por meio de um questionário, foram coletados os dados demográficos e o perfil socioeconômico e por meio de exame clínico foram obtidos o perfil nosológico e o perfil da pressão arterial e das perdas dentais. Os resultados evidenciaram que 52% dos pacientes eram do sexo feminino, com idad...

  1. Ambulatory monitoring in the diagnosis and management of obstructive sleep apnoea syndrome

    Directory of Open Access Journals (Sweden)

    Jaime Corral-Peñafiel

    2013-09-01

    Full Text Available Obstructive sleep apnoea (OSA is a highly prevalent disorder associated with complications such as arterial hypertension, cardiovascular diseases and traffic accidents. The resources allocated for OSA are insufficient and OSA is a significant public health problem. Portable recording devices have been developed for the detection of OSA syndrome and have proved capable of providing an equivalent diagnosis to in-laboratory polysomnography (PSG, at least in patients with a high pre-test probability of OSA syndrome. PSG becomes important in patients who have symptoms and certain comorbidities such as chronic obstructive pulmonary disease or stroke, as well as in patients with a clinical history suggesting a different sleep disorder. Continuous positive airway pressure is the most effective treatment in OSA. Ambulatory monitoring of the therapeutic modalities has been evaluated to enhance the care process and reduce costs compared to the conventional approach, without sacrificing efficiency. This review evaluates the role of portable monitoring devices in the diagnostic process of OSA and the search for alternative strategies based on ambulatory management protocols.

  2. Аrterial stiffness and cardiovascular autonomic neuropathy relationship in children and adolescents with type 1 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Dmitriy Nikitich Laptev

    2015-03-01

    Full Text Available AimTo evolve the association between cardiac autonomic function and arterial stiffness in children and adolescents with type 1 diabetes mellitus (T1DM.Materials and methods72 T1DM patients aged 7–18 years without history of macrovascular complications or renal disease, including microalbuminuria, were involved in the study. Cardiac function was assessed by the cardiovascular tests and 24-hour ECG monitoring with automatic calculation of QT interval and heart rate variability (HRV parameters. Artery stiffness was assessed by measurement of pulse wave velocity (PWV and augmentation index (AI obtained from arterial blood pressure monitoring for 24 hours.ResultsEstimated prevalence of cardiovascular autonomic neuropathy (CAN was 31,9%. CAN+ patients had significantly higher PWV and AI than those without CAN. A negative correlation between PWV and AI with some cardiovascular tests and HRV parameters was observed. In multivariable analysis, AI was independent predictor of autonomic dysfunction defined as number of positive cardiovascular tests, HRV parameters below normal values and prolongation of QT interval (β=0,18; p=0,035.ConclusionCardiac autonomic function is an independent predictor of arterial stiffness, in children and adolescents with T1D without macrovascular and renal complications. The presence of cardiovascular risk factors and arterial stiffness in children and adolescents with T1DM may contribute to the increased cardiovascular morbidity and mortality in adulthood in patients with CAN.

  3. Computerized adaptive testing--ready for ambulatory monitoring?

    DEFF Research Database (Denmark)

    Rose, Matthias; Bjørner, Jakob; Fischer, Felix

    2012-01-01

    Computerized adaptive tests (CATs) have abundant theoretical advantages over established static instruments, which could improve ambulatory monitoring of patient-reported outcomes (PROs). However, an empirical demonstration of their practical benefits is warranted....

  4. Ambulatory Pessary Trial Unmasks Occult Stress Urinary Incontinence

    Directory of Open Access Journals (Sweden)

    Bilal Chughtai

    2012-01-01

    Conclusion. An ambulatory pessary trial is an effective, easy, and inexpensive method to approximate anatomic results achieved by surgery under real-life conditions. In our series, 20% of patients with occult SUI were identified by pessary trial alone.

  5. Stiffness estimation of a parallel kinematic machine

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper presents a simple yet comprehensive approach to quickly estimating the stiff-ness of a tripod-based parallel kinematic machine. This approach can be implemented in two steps. Inthe first step, the machine structure is decomposed into two substructures associated with the machineframe and parallel mechanism. The stiffness models of these two substructures are formulated bymeans of virtual work principle. This is followed by the second step that enables the stiffness model ofthe machine structure as a whole to be achieved by linear superposition. The 3D representations of themachine stiffness within the usable workspace are depicted and the contributions of different componentrigidities to the machine stiffness are discussed. The result is compared with that obtained through finiteelement analysis.

  6. Arterial stiffening precedes systolic hypertension in diet-induced obesity.

    Science.gov (United States)

    Weisbrod, Robert M; Shiang, Tina; Al Sayah, Leona; Fry, Jessica L; Bajpai, Saumendra; Reinhart-King, Cynthia A; Lob, Heinrich E; Santhanam, Lakshmi; Mitchell, Gary; Cohen, Richard A; Seta, Francesca

    2013-12-01

    Stiffening of conduit arteries is a risk factor for cardiovascular morbidity. Aortic wall stiffening increases pulsatile hemodynamic forces that are detrimental to the microcirculation in highly perfused organs, such as the heart, brain, and kidney. Arterial stiffness is associated with hypertension but presumed to be due to an adaptive response to increased hemodynamic load. In contrast, a recent clinical study found that stiffness precedes and may contribute to the development of hypertension although the mechanisms underlying hypertension are unknown. Here, we report that in a diet-induced model of obesity, arterial stiffness, measured in vivo, develops within 1 month of the initiation of the diet and precedes the development of hypertension by 5 months. Diet-induced obese mice recapitulate the metabolic syndrome and are characterized by inflammation in visceral fat and aorta. Normalization of the metabolic state by weight loss resulted in return of arterial stiffness and blood pressure to normal. Our findings support the hypothesis that arterial stiffness is a cause rather than a consequence of hypertension.

  7. Numerical Analysis of Plastic Gear Stiffness

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    This paper established practical 3-D gear models to study the stiffness influencing factors of a loaded gear by finite element method, such as friction parameters, material properties, and gear structures. The research shows that, in elastic deformation, gear stiffness increases when sliding friction ability of contact pair decreases;meanwhile, the gear structure, especially asymmetric design in gear's shaft direction will also decrease gear stiffness.

  8. Pros and cons of the ambulatory surgery center joint venture.

    Science.gov (United States)

    Giannini, Deborah

    2008-01-01

    If a physician group has determined that it has a realistic patient base to establish an ambulatory surgery center, it may be beneficial to consider a partner to share the costs and risks of this new joint venture. Joint ventures can be a benefit or liability in the establishment of an ambulatory surgery center. This article discusses the advantages and disadvantages of a hospital physician-group joint venture.

  9. WAY TO DETERMINE STIFFNESS FUNCTION OF STRUCTURE

    Institute of Scientific and Technical Information of China (English)

    WANG De-ming; GAI Bing-zheng

    2005-01-01

    For calculating the stiffness function of a structure, the differential equation of the vibration of the structure was divided into the differential equation on the original stiffness function that was known, and Fredholm integral equation of the first kind on the undetermined stiffness function that was unknown. And the stable solutions of the integral equation, when the smooth factor was equal to zero, was solved by the extrapolation with p smooth factors. So the stiffness function of the structure is obtained. Applied examples show that the method is feasible and effective.

  10. A new approach to determine press stiffness

    DEFF Research Database (Denmark)

    Arentoft, Mogens; Wanheim, Tarras

    2004-01-01

    A new procedure is proposed for measuring press stiffness, including separated horizontal and vertical loading of the press frame. The load can be eccentrically positioned for measuring rotational stiffnesses. Two loading devices and corresponding measuring equipment for registration of press...... deflections are designed. The press stiffness is presented as a 6 by 6 flexibility matrix. The approach has been tested by measuring the stiffness of a 5000 kN O-frame, ring element, hydraulic press, a 10000 kN O-frame, pillar element, hydraulic press and a 10000 kN O-frame, ring element mechanical press...

  11. Hereditary and environmental influences on arterial function.

    Science.gov (United States)

    Hayward, C S; Benetos, A

    2007-07-01

    1. With the ageing population and increasing heart failure, arterial function has been shown to contribute to cardiovascular risk because of its adverse effects on ventriculovascular coupling. Population studies have confirmed independent prognostic information of arterial stiffening on cardiovascular survival. 2. The term 'arterial function' encompasses a range of phenotypes, including measures of arterial structure/remodelling, measures of arterial wall mechanics, surrogate measures of stiffness and of wave reflection. There exists significant interaction between these measures and none is truly independent of the others. Added to this complexity is the recognition that, although arterial function has a strong genetic component, quantification requires a range of techniques from twin to family and population studies. 3. The contribution of heritability is often derived from statistical models with input from genomic scanning and candidate gene studies. Studies to date confirm a significant heritable component for the majority of phenotypes examined. However, it has also been recognized that the factors involved in blood pressure maintenance are likely to be separate to those in arterial structural degeneration with ageing. Candidate genes for arterial function go beyond those of the sympathetic and renin-angiotensin systems and include genes involved in signalling pathways and extracellular matrix modulation. 4. The present review examines the evidence for heritability of the major arterial function phenotypes with environmental and ageing modulation. A brief overview of the impact of atherosclerotic risk factors on arterial function is included.

  12. Fluid shifts, vasodilatation and ambulatory blood pressure reduction during long duration spaceflight

    DEFF Research Database (Denmark)

    Norsk, Peter; Asmar, Ali; Damgaard, Morten;

    2015-01-01

    KEY POINTS: Weightlessness in space induces initially an increase in stroke volume and cardiac output, accompanied by unchanged or slightly reduced blood pressure.It is unclear whether these changes persist throughout months of flight.Here, we show that cardiac output and stroke volume increase...... by 35–41% between 3 and 6 months on the International Space Station, which is more than during shorter flights.Twenty-four hour ambulatory brachial blood pressure is reduced by 8–10 mmHg by a decrease in systemic vascular resistance of 39%, which is not a result of the suppression of sympathetic nervous...... brachial arterial pressures were automatically recorded at 1–2 h intervals with portable equipment in eight male astronauts: once before launch, once between 85 and 192 days in space on the International Space Station and, finally, once at least 2 months after flight. During the same 24 h, cardiac output...

  13. Acute arterial occlusion - kidney

    Science.gov (United States)

    Acute renal arterial thrombosis; Renal artery embolism; Acute renal artery occlusion; Embolism - renal artery ... kidney can often result in permanent kidney failure. Acute arterial occlusion of the renal artery can occur after injury or trauma to ...

  14. Analysis of Arterial Mechanics During Head-down Tilt Bed Rest

    Science.gov (United States)

    Elliot, Morgan; Martin, David S.; Westby, Christian M.; Stenger, Michael B.; Platts, Steve

    2014-01-01

    Arterial health may be affected by microgravity or ground based analogs of spaceflight, as shown by an increase in thoracic aorta stiffness1. Head-down tilt bed rest (HDTBR) is often used as a ground-based simulation of spaceflight because it induces physiological changes similar to those that occur in space2, 3. This abstract details an analysis of arterial stiffness (a subclinical measure of atherosclerosis), the distensibility coefficient (DC), and the pressure-strain elastic modulus (PSE) of the arterial walls during HDTBR. This project may help determine how spaceflight differentially affects arterial function in the upper vs. lower body.

  15. Vertical Dynamic Stiffness of Offshore Foundations

    DEFF Research Database (Denmark)

    Latini, Chiara; Cisternino, Michele; Zania, Varvara

    2016-01-01

    ) is investigated by numerical analyses of representative finite element models. The 3D numerical model is compared and validated with existing analytical solutions. A parametric study is carried out analyzing the effect of the slenderness ratio Hp/d and the height and the stiffness of the soil layer on the dynamic...... stiffness and damping....

  16. Stiff person syndrome: a case report.

    Science.gov (United States)

    Kelly, Patricia A; Kuberski, Carolyn

    2014-08-01

    The case report features a patient who had a diagnosis of a common type of breast cancer with an uncommon neurologic syndrome. She had extreme pain and progressive stiffness with cognitive and functional decline. This article includes the pathogenesis and treatment options for a rare, but treatable, autoimmune disorder of malignancy called stiff person syndrome.

  17. Continuous ambulatory peritoneal dialysis: Indian scenario.

    Science.gov (United States)

    Abraham, Georgi; Mathew, Milli; Hinduja, Anish; Padma, G

    2002-03-01

    Chronic peritoneal dialysis (CPD) has been initiated as a treatment modality for chronic renal failure patients in the Indian subcontinent since 1990. Over a period of 9 years both continuous ambulatory peritoneal dialysis (CAPD) and continuous cyclic peritoneal dialysis (CCPD) have emerged as accepted forms of renal replacement therapy in our country. Although there were government restrictions on import of dialysis fluid until 1993, the availability of locally manufactured fluid in collapsible bags had facilitated the expansion of the programme to the far corners of the country and in neighbouring countries. Initially majority (78%) of the patients who were started on this programme were diabetics with other comorbid conditions who were drop-outs from haemodialysis and unfit for transplantation. Both CAPD and CCPD have been used for all age groups and for men and women. Majority of the patients do 3 x 2 l exchanges a day on CAPD; 8-10 l using a cycler at night those who are onCCPD. Peritonitis rate was 1 episode every 18 patient months. With the introduction of new connection and disposable sets the incidence of peritonitis is dropping down. The major cause of drop-out is cardiovascular death followed by peritonitis. Malnutrition is a major problem in both CAPD and haemodialysis patients. The programme has been expanded and there are over one thousand patients on this treatment in the country. The introduction of CPD had a major impact on the treatment of renal failure in India.

  18. Heart transplantation and arterial elasticity

    Directory of Open Access Journals (Sweden)

    Colvin-Adams M

    2013-12-01

    Full Text Available Monica Colvin-Adams,1 Nonyelum Harcourt,1 Robert LeDuc,2 Ganesh Raveendran,1 Yassir Sonbol,3 Robert Wilson,1 Daniel Duprez11Cardiovascular Division, University of Minnesota, Minneapolis, MN, USA; 2Division of Biostatistics University of Minnesota, Minneapolis, MN, USA; 3Cardiovascular Division, St Luke's Hospital System, Sugar Land, TX, USAObjective: Arterial elasticity is a functional biomarker that has predictive value for cardiovascular morbidity and mortality in nontransplant populations. There is little information regarding arterial elasticity in heart transplant recipients. This study aimed to characterize small (SAE and large (LAE artery elasticity in heart transplant recipients in comparison with an asymptomatic population free of overt cardiovascular disease. A second goal was to identify demographic and clinical factors associated with arterial elasticity in this unique population.Methods: Arterial pulse waveform was registered noninvasively at the radial artery in 71 heart transplant recipients between 2008 and 2010. SAEs and LAEs were derived from diastolic pulse contour analysis. Comparisons were made to a healthy cohort of 1,808 participants selected from our prevention clinic database. Multiple regression analyses were performed to evaluate associations between risk factors and SAE and LAE within the heart transplant recipients.Results: LAE and SAE were significantly lower in heart transplant recipients than in the normal cohort (P <0.01 and P < 0.0001, respectively. Female sex and history of ischemic cardiomyopathy were significantly associated with reduced LAE and SAE. Older age and the presence of moderate cardiac allograft vasculopathy were also significantly associated with reduced SAE. Transplant duration was associated with increased SAE.Conclusion: Heart transplants are associated with peripheral endothelial dysfunction and arterial stiffness, as demonstrated by a significant reduction in SAE and LAE when compared with a

  19. Cuff inflation during ambulatory blood pressure monitoring and heart rate

    Directory of Open Access Journals (Sweden)

    Mia Skov-Madsen

    2008-11-01

    Full Text Available Mia Skov-Madsen, My Svensson, Jeppe Hagstrup ChristensenDepartment of Nephrology, Aarhus University Hospital, Aalborg, DenmarkIntroduction: Twenty four-hour ambulatory blood pressure monitoring is a clinically validated procedure in evaluation of blood pressure (BP. We hypothesised that the discomfort during cuff inflation would increase the heart rate (HR measured with 24-h ambulatory BP monitoring compared to a following HR measurement with a 24-h Holter monitor.Methods: The study population (n = 56 were recruited from the outpatient’s clinic at the Department of Nephrology, Aalborg Hospital, Aarhus University Hospital at Aalborg, Denmark. All the patients had chronic kidney disease (CKD. We compared HR measured with a 24-h Holter monitor with a following HR measured by a 24-h ambulatory BP monitoring.Results: We found a highly significant correlation between the HR measured with the Holter monitor and HR measured with 24-h ambulatory blood pressure monitoring (r = 0.77, p < 0.001. Using the Bland-Altman plot, the mean difference in HR was only 0.5 beat/min during 24 hours with acceptable limits of agreement for both high and low HR levels. Dividing the patients into groups according to betablocker treatment, body mass index, age, sex, angiotensin-converting enzyme inhibitor treatment, statins treatment, diuretic treatment, or calcium channel blocker treatment revealed similar results as described above.Conclusion: The results indicate that the discomfort induced by cuff inflation during 24-h ambulatory BP monitoring does not increase HR. Thus, 24-h ambulatory BP monitoring may be a reliable measurement of the BP among people with CKD.Keywords: ambulatory blood pressure monitoring, Holter monitoring, heart rate, chronic kidney disease, hypertension

  20. Surgical Site Infections Following Pediatric Ambulatory Surgery: An Epidemiologic Analysis.

    Science.gov (United States)

    Rinke, Michael L; Jan, Dominique; Nassim, Janelle; Choi, Jaeun; Choi, Steven J

    2016-08-01

    OBJECTIVE To identify surgical site infection (SSI) rates following pediatric ambulatory surgery, SSI outcomes and risk factors, and sensitivity and specificity of SSI administrative billing codes. DESIGN Retrospective chart review of pediatric ambulatory surgeries with International Classification of Disease, Ninth Revision (ICD-9) codes for SSI, and a systematic random sampling of 5% of surgeries without SSI ICD-9 codes, all adjudicated for SSI on the basis of an ambulatory-adapted National Healthcare Safety Network definition. SETTING Urban pediatric tertiary care center April 1, 2009-March 31, 2014. METHODS SSI rates and sensitivity and specificity of ICD-9 codes were estimated using sampling design, and risk factors were analyzed in case-rest of cohort, and case-control, designs. RESULTS In 15,448 pediatric ambulatory surgeries, 34 patients had ICD-9 codes for SSI and 25 met the adapted National Healthcare Safety Network criteria. One additional SSI was identified with systematic random sampling. The SSI rate following pediatric ambulatory surgery was 2.9 per 1,000 surgeries (95% CI, 1.2-6.9). Otolaryngology surgeries demonstrated significantly lower SSI rates compared with endocrine (P=.001), integumentary (P=.001), male genital (Psurgeries. Almost half of patients with an SSI were admitted, 88% received antibiotics, and 15% returned to the operating room. No risk factors were associated with SSI. The sensitivity of ICD-9 codes for SSI following ambulatory surgery was 55.31% (95% CI, 12.69%-91.33%) and specificity was 99.94% (99.89%-99.97%). CONCLUSIONS SSI following pediatric ambulatory surgery occurs at an appreciable rate and conveys morbidity on children. Infect Control Hosp Epidemiol 2016;37:931-938.

  1. Stiffness Control of Surgical Continuum Manipulators

    Science.gov (United States)

    Mahvash, Mohsen; Dupont, Pierre E.

    2013-01-01

    This paper introduces the first stiffness controller for continuum robots. The control law is based on an accurate approximation of a continuum robot’s coupled kinematic and static force model. To implement a desired tip stiffness, the controller drives the actuators to positions corresponding to a deflected robot configuration that produces the required tip force for the measured tip position. This approach provides several important advantages. First, it enables the use of robot deflection sensing as a means to both sense and control tip forces. Second, it enables stiffness control to be implemented by modification of existing continuum robot position controllers. The proposed controller is demonstrated experimentally in the context of a concentric tube robot. Results show that the stiffness controller achieves the desired stiffness in steady state, provides good dynamic performance, and exhibits stability during contact transitions. PMID:24273466

  2. Rolling Element Bearing Stiffness Matrix Determination (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Y.; Parker, R.

    2014-01-01

    Current theoretical bearing models differ in their stiffness estimates because of different model assumptions. In this study, a finite element/contact mechanics model is developed for rolling element bearings with the focus of obtaining accurate bearing stiffness for a wide range of bearing types and parameters. A combined surface integral and finite element method is used to solve for the contact mechanics between the rolling elements and races. This model captures the time-dependent characteristics of the bearing contact due to the orbital motion of the rolling elements. A numerical method is developed to determine the full bearing stiffness matrix corresponding to two radial, one axial, and two angular coordinates; the rotation about the shaft axis is free by design. This proposed stiffness determination method is validated against experiments in the literature and compared to existing analytical models and widely used advanced computational methods. The fully-populated stiffness matrix demonstrates the coupling between bearing radial, axial, and tilting bearing deflections.

  3. Measurement and Treatment of Passive Muscle Stiffness

    DEFF Research Database (Denmark)

    Kirk, Henrik

    2016-01-01

    This PhD thesis is based on research conducted at the University of Copenhagen and Helene Elsass Center from 2012 to 2015. Measurements and treatment of passive muscle stiffness in people with cerebral palsy (CP) comprise the focus of the thesis. The thesis summarizes the results from four studies......, which aimed to investigate: 1) The development of a clinical method to evaluate and distinguish neural (reflex mediated stiffness) and non-neural (passive muscle stiffness) components of muscle stiffness in adults with CP by objective and reliable measurements 2) The association between increased......, and good correlation to measurements from a stationary dynamometer. The second part of the thesis discusses the finding of a significant correlation between gait function, reduced rate of force development (RFD), and increased passive muscle stiffness in adults with CP. Previously, the reflex...

  4. Determination of 6 stiffnesses for a press

    DEFF Research Database (Denmark)

    Arentoft, Mogens; Eriksen, Morten; Wanheim, Tarras

    2000-01-01

    the workpiece will result in deflections of the press, which will decrease the tolerances of the component. At present, it is possible to measure the reaction forces from the workpiece, for instance by use of the model material technique as described in [1-2]. If the stiffness and clearances of the press...... is known too, the final dimensions can be predicted by divide the force by the stiffness and add the clearance. If the stiffness of the press is known, it is possible to optimize the orientation of the workpiece too, so the direction, in which the best tolerances is demanded, is equal to the direction...... in which the press has the highest stiffness. Furthermore, knowledge about the stiffnesses of all presses in a production system makes it possible to choose the press which best fit to a specific process....

  5. Advances in the use of intravenous techniques in ambulatory anesthesia

    Directory of Open Access Journals (Sweden)

    Eng MR

    2015-07-01

    Full Text Available Matthew R Eng,1 Paul F White1,2 1Department of Anesthesiology, Cedars-Sinai Medical Center, Los Angeles, CA, USA; 2White Mountain Institute, The Sea Ranch, CA, USA Summary statement: Advances in the use of intravenous techniques in ambulatory anesthesia has become important for the anesthesiologist as the key perioperative physician in outpatient surgery. Key techniques and choices of anesthetics are important in accomplishing fast track goals of ambulatory surgery. Purpose of review: The anesthesiologist in the outpatient environment must focus on improving perioperative efficiency and reducing recovery times while accounting for patients' well-being and safety. This review article focuses on recent intravenous anesthetic techniques to accomplish these goals. Recent findings: This review is an overview of techniques in intravenous anesthesia for ambulatory anesthesia. Intravenous techniques may be tailored to accomplish outpatient surgery goals for the type of surgical procedure and individual patient needs. Careful anesthetic planning and the application of the plans are critical to an anesthesiologist's success with fast-track ambulatory surgery. Conclusion: Careful planning and application of intravenous techniques are critical to an anesthesiologist's success with fast-track ambulatory surgery. Keywords: intravenous anesthesia, outpatient anesthesia, fast-track surgery

  6. Ambulatory anesthesia in plastic surgery: opportunities and challenges

    Directory of Open Access Journals (Sweden)

    Facque AR

    2015-10-01

    Full Text Available Alexander R Facque, Peter J Taub Division of Plastic and Reconstructive Surgery, Department of Surgery, Mount Sinai Medical Center, New York, NY, USA Abstract: In 2013, there were 17 million procedures performed by plastic and reconstructive surgeons in the United States in the private office or ambulatory “surgicenter” setting, as well as additional operations performed in hospitals on an outpatient basis. As interest in performing increasingly complex surgical procedures on an outpatient basis continues to grow, the surgeon and anesthesiologist alike must be prepared to offer safe and reliable anesthesia and analgesia in the ambulatory setting. Surgeons must be aware of the possible techniques that will be employed in their surgeries in order to anticipate and prepare patients for possible postoperative side effects, and anesthesiologists must be prepared to offer such techniques in order to ensure a relatively rapid return to normal activity despite potentially having undergone major surgery. The following is a review of the specific considerations that should be given to ambulatory plastic surgery patients with comments on recent developments in the techniques used to safely administer agreeable and effective anesthesia. Keywords: ambulatory surgery, cosmetic anesthesia, outpatient, ambulatory anesthesia

  7. Patient satisfaction and positive patient outcomes in ambulatory anesthesia

    Directory of Open Access Journals (Sweden)

    Shah U

    2015-04-01

    Full Text Available Ushma Shah, David T Wong, Jean Wong Department of Anesthesia, Toronto Western Hospital, University Health Network, University of Toronto, Toronto, ON, Canada Abstract: Most surgeries in North America are performed on an ambulatory basis, reducing health care costs and increasing patient comfort. Patient satisfaction is an important outcome indicator of the quality of health care services incorporated by the American Society of Anesthesiologists (ASA. Patient satisfaction is a complex concept that is influenced by multiple factors. A patient's viewpoint and knowledge plays an influential role in patient satisfaction with ambulatory surgery. Medical optimization and psychological preparation of the patient plays a pivotal role in the success of ambulatory surgery. Postoperative pain, nausea, and vomiting are the most important symptoms for the patient and can be addressed by multimodal drug regimens. Shared decision making, patient–provider relationship, communication, and continuity of care form the main pillars of patient satisfaction. Various psychometrically developed instruments are available to measure patient satisfaction, such as the Iowa Satisfaction with Anesthesia Scale and Evaluation du Vecu de I'Anesthesie Generale, but none have been developed specifically for ambulatory surgery. The ASA has made recommendations for data collection for patient satisfaction surveys and emphasized the importance of reporting the data to the Anesthesia Quality Institute. Future research is warranted to develop a validated tool to measure patient satisfaction in ambulatory surgery. Keywords: patient, satisfaction, anesthesia, outcomes, questionnaire, perspectives

  8. Ambulatory laparoscopic cholecystectomy: A single center experience

    Directory of Open Access Journals (Sweden)

    Cagri Tiryaki

    2016-01-01

    Full Text Available Aim: To evaluate the demographic and clinical parameters affecting the outcomes of ambulatory laparoscopic cholecystectomy (ALC in terms of pain, nausea, anxiety level, and satisfaction of patients in a tertiary health center. Materials and Methods: ALC was offered to 60 patients who met the inclusion criteria. Follow-up (questioning for postoperative pain or discomfort, nausea or vomiting, overall satisfaction was done by telephone contact on the same day at 22:00 p.m. and the first day after surgery at 8: 00 a.m. and by clinical examination one week after operation. STAI I and II data were used for proceeding to the level of anxiety of patients before and/or after the operation. Results: Sixty consecutive patients, with a mean age of 40.6 ± 8.1 years underwent ALC. Fifty-five (92% patients could be sent to their homes on the same day but five patients could not be sent due to anxiety, pain, or social indications. Nausea was reported in four (6.7% cases and not associated with any demographic or clinical features of patients. On the other hand, pain has been reported in 28 (46.7% cases, and obesity and shorter duration of gallbladder disease were associated with the increased pain perception (P = 0.009 and 0.004, respectively. Preopereative anxiety level was significantly higher among patients who could not complete the ALC procedure (P = 0.018. Conclusion: Correct management of these possible adverse effects results in the increased satisfaction of patients and may encourage this more cost-effective and safe method of laparoscopic cholecystectomy.

  9. Stiff substrates enhance cultured neuronal network activity.

    Science.gov (United States)

    Zhang, Quan-You; Zhang, Yan-Yan; Xie, Jing; Li, Chen-Xu; Chen, Wei-Yi; Liu, Bai-Lin; Wu, Xiao-an; Li, Shu-Na; Huo, Bo; Jiang, Lin-Hua; Zhao, Hu-Cheng

    2014-08-28

    The mechanical property of extracellular matrix and cell-supporting substrates is known to modulate neuronal growth, differentiation, extension and branching. Here we show that substrate stiffness is an important microenvironmental cue, to which mouse hippocampal neurons respond and integrate into synapse formation and transmission in cultured neuronal network. Hippocampal neurons were cultured on polydimethylsiloxane substrates fabricated to have similar surface properties but a 10-fold difference in Young's modulus. Voltage-gated Ca(2+) channel currents determined by patch-clamp recording were greater in neurons on stiff substrates than on soft substrates. Ca(2+) oscillations in cultured neuronal network monitored using time-lapse single cell imaging increased in both amplitude and frequency among neurons on stiff substrates. Consistently, synaptic connectivity recorded by paired recording was enhanced between neurons on stiff substrates. Furthermore, spontaneous excitatory postsynaptic activity became greater and more frequent in neurons on stiff substrates. Evoked excitatory transmitter release and excitatory postsynaptic currents also were heightened at synapses between neurons on stiff substrates. Taken together, our results provide compelling evidence to show that substrate stiffness is an important biophysical factor modulating synapse connectivity and transmission in cultured hippocampal neuronal network. Such information is useful in designing instructive scaffolds or supporting substrates for neural tissue engineering.

  10. Dynamic stiffness of suction caissons - vertical vibrations

    Energy Technology Data Exchange (ETDEWEB)

    Ibsen, Lars Bo; Liingaard, M.; Andersen, Lars

    2006-12-15

    The dynamic response of offshore wind turbines are affected by the properties of the foundation and the subsoil. The purpose of this report is to evaluate the dynamic soil-structure interaction of suction caissons for offshore wind turbines. The investigation is limited to a determination of the vertical dynamic stiffness of suction caissons. The soil surrounding the foundation is homogenous with linear viscoelastic properties. The dynamic stiffness of the suction caisson is expressed by dimensionless frequency-dependent dynamic stiffness coefficients corresponding to the vertical degree of freedom. The dynamic stiffness coefficients for the foundations are evaluated by means of a dynamic three-dimensional coupled Boundary Element/Finite Element model. Comparisons are made with known analytical and numerical solutions in order to evaluate the static and dynamic behaviour of the Boundary Element/Finite Element model. The vertical frequency dependent stiffness has been determined for different combinations of the skirt length, Poisson's ratio and the ratio between soil stiffness and skirt stiffness. Finally the dynamic behaviour at high frequencies is investigated. (au)

  11. Cooperative effects of matrix stiffness and fluid shear stress on endothelial cell behavior.

    Science.gov (United States)

    Kohn, Julie C; Zhou, Dennis W; Bordeleau, François; Zhou, Allen L; Mason, Brooke N; Mitchell, Michael J; King, Michael R; Reinhart-King, Cynthia A

    2015-02-03

    Arterial hemodynamic shear stress and blood vessel stiffening both significantly influence the arterial endothelial cell (EC) phenotype and atherosclerosis progression, and both have been shown to signal through cell-matrix adhesions. However, the cooperative effects of fluid shear stress and matrix stiffness on ECs remain unknown. To investigate these cooperative effects, we cultured bovine aortic ECs on hydrogels matching the elasticity of the intima of compliant, young, or stiff, aging arteries. The cells were then exposed to laminar fluid shear stress of 12 dyn/cm(2). Cells grown on more compliant matrices displayed increased elongation and tighter EC-cell junctions. Notably, cells cultured on more compliant substrates also showed decreased RhoA activation under laminar shear stress. Additionally, endothelial nitric oxide synthase and extracellular signal-regulated kinase phosphorylation in response to fluid shear stress occurred more rapidly in ECs cultured on more compliant substrates, and nitric oxide production was enhanced. Together, our results demonstrate that a signaling cross talk between stiffness and fluid shear stress exists within the vascular microenvironment, and, importantly, matrices mimicking young and healthy blood vessels can promote and augment the atheroprotective signals induced by fluid shear stress. These data suggest that targeting intimal stiffening and/or the EC response to intima stiffening clinically may improve vascular health.

  12. Arterial mechanics at rest and during exercise in adolescents and young adults after arterial switch operation for complete transposition of the great arteries.

    Science.gov (United States)

    Chen, Robin H; Wong, Sophia J; Wong, Wilfred H; Cheung, Yiu-Fai

    2014-02-15

    We sought to determine the arterial mechanics at rest and during exercise in adolescents and young adults with complete transposition of the great arteries after arterial switch operation and their relations with neoaortic complications. Thirty patients (22 men) aged 16.2 ± 2.1 years and 22 controls (15 men) were studied. Central and peripheral arterial pulse wave velocities, carotid and radial augmentation indices, and central systolic blood pressure (cSBP) were determined by oscillometry and applanation tonometry, whereas arterial dimensions were measured by 2-dimensional echocardiography. Arterial strain, distensibility, and stiffness were determined at rest and during supine bicycle exercise testing. At rest, patients had significantly higher heart-carotid pulse wave velocity, carotid and radial augmentation indices, and cSBP than controls. At rest and during submaximal exercise, patients had significantly lower aortic strain and distensibility, greater aortic and carotid stiffness, and higher SBP than controls. Dilated aortic sinus found in 23 (76.7%) patients was associated with lower aortic distensibility, greater aortic stiffness, and higher cSBP at rest and lower aortic distensibility and strain at submaximal exercise. Significant aortic regurgitation found in 20% (6 of 30) of patients was associated with significantly higher neoaortic z scores. Multivariate analysis identified aortic stiffness at rest (β = 0.46, p = 0.003) and age at operation (β = 0.44, p = 0.004) as significant determinants of aortic sinus z scores. In conclusion, altered mechanics of the central arteries are present at rest and during exercise in adolescents and young adults after arterial switch operation. These findings may have important implications on progression of neoaortic root dilation, exercise recommendations, and medical therapy.

  13. Accelerated Solutions for Transcendental Stiffness Matrix Eigenproblems

    Directory of Open Access Journals (Sweden)

    F.W. Williams

    1996-01-01

    Full Text Available This article outlines many existing and forthcoming methods that can be used alone, or in various combinations, to accelerate the solutions of the transcendental stiffness matrix eigenproblems that arise when the stiffness matrix is assembled from exact member stiffnesses, which are obtained by solving the member differential equations exactly. Thus distributed member mass and/or the flexural effect of axial loading are incorporated exactly, and the solutions are the natural frequencies for vibration problems or the critical load factors for buckling problems.

  14. Pediatric ambulatory blood pressure monitoring: indications and interpretations.

    Science.gov (United States)

    Flynn, Joseph T; Urbina, Elaine M

    2012-06-01

    The prevalence of hypertension in children and adolescents is increasing, especially in obese and ethnic children. The adverse long-term effects of hypertension beginning in youth are known; therefore, it is important to identify young patients who need intervention. Unfortunately, measuring blood pressure (BP) is difficult due to the variety of techniques available and innate biologic variation in BP levels. Ambulatory BP monitoring may overcome some of the challenges clinicians face when attempting to categorize a young patient's BP levels. In this article, the authors review the use of ambulatory BP monitoring in pediatrics, discuss interpretation of ambulatory BP monitoring, and discuss gaps in knowledge in usage of this technique in the management of pediatric hypertension.

  15. Abordagem ambulatorial do nutricionista em anemia hemolítica Nutritional ambulatory approach in hemolytic anemia

    Directory of Open Access Journals (Sweden)

    Maria Aparecida Vieira

    1999-04-01

    Full Text Available Descreve a atuação do nutricionista em ambulatório de Hematologia Pediátrica em um hospital escola e relata as condutas dietéticas necessárias na abordagem de crianças com anemia hemolítica com e sem sobrecarga de ferro, e também as atitudes mais freqüentes dos familiares em relação à alimentação desses pacientes.The Authors describe the performance of the Dietitian in a Pediatric Hematology Ambulatory. They emphasize the necessary dietetic procedures for adequate management of children with hemolytic anemia, with and without iron overload. Furthermore, they approach the family's attitude towards the patient's nutrition.

  16. Abnormal arterial flows by a distributed model of the fetal circulation.

    Science.gov (United States)

    van den Wijngaard, Jeroen P H M; Westerhof, Berend E; Faber, Dirk J; Ramsay, Margaret M; Westerhof, Nico; van Gemert, Martin J C

    2006-11-01

    Modeling the propagation of blood pressure and flow along the fetoplacental arterial tree may improve interpretation of abnormal flow velocity waveforms in fetuses. The current models, however, either do not include a wide range of gestational ages or do not account for variation in anatomical, vascular, or rheological parameters. We developed a mathematical model of the pulsating fetoumbilical arterial circulation using Womersley's oscillatory flow theory and viscoelastic arterial wall properties. Arterial flow waves are calculated at different arterial locations from which the pulsatility index (PI) can be determined. We varied blood viscosity, placental and brain resistances, placental compliance, heart rate, stiffness of the arterial wall, and length of the umbilical arteries. The PI increases in the umbilical artery and decreases in the cerebral arteries, as a result of increasing placental resistance or decreasing brain resistance. Both changes in resistance decrease the flow through the placenta. An increased arterial stiffness increases the PIs in the entire fetoplacental circulation. Blood viscosity and peripheral bed compliance have limited influence on the flow profiles. Bradycardia and tachycardia increase and decrease the PI in all arteries, respectively. Umbilical arterial length has limited influence on the PI but affects the mean arterial pressure at the placental cord insertion. The model may improve the interpretation of arterial flow pulsations and thus may advance both the understanding of pathophysiological processes and clinical management.

  17. Twenty-four-hour ambulatory blood pressure in children with sleep-disordered breathing.

    Science.gov (United States)

    Amin, Raouf S; Carroll, John L; Jeffries, Jenny L; Grone, Charles; Bean, Judy A; Chini, Barbara; Bokulic, Ronald; Daniels, Stephen R

    2004-04-15

    Obstructive sleep apnea causes intermittent elevation of systemic blood pressure (BP) during sleep. To determine whether obstructive apnea in children has a tonic effect on diurnal BP, 24-hour ambulatory blood pressure was obtained from 60 children with mean age of 10.8 +/- 3.5 years. Thirty-nine children had obstructive apnea and 21 had primary snoring. Children with obstructive apnea had significantly greater mean BP variability during wakefulness and sleep, a higher night-to-day systolic BP, and a smaller nocturnal dipping of mean BP. Variability of mean arterial pressure during wakefulness was predicted by the desaturation, body mass, and arousal indices, whereas variability during sleep was predicted by apnea-hypopnea and body mass indices. Nocturnal BP dipping was predicted by the desaturation index. There were no significant differences in systolic, diastolic, or mean arterial BP during sleep between the groups. Diastolic BP during wakefulness was significantly different between the groups and correlated negatively with apnea-hypopnea index. We conclude that obstructive apnea in children is associated with 24-hour BP dysregulation and that, independent of obesity, the frequency of obstructive apnea, oxygen desaturation, and arousal contributes to abnormal BP control.

  18. Social support and ambulatory blood pressure: an examination of both receiving and giving.

    Science.gov (United States)

    Piferi, Rachel L; Lawler, Kathleen A

    2006-11-01

    The relationship between the social network and physical health has been studied extensively and it has consistently been shown that individuals live longer, have fewer physical symptoms of illness, and have lower blood pressure when they are a member of a social network than when they are isolated. Much of the research has focused on the benefits of receiving social support from the network and the effects of giving to others within the network have been neglected. The goal of the present research was to systematically investigate the relationship between giving and ambulatory blood pressure. Systolic blood pressure, diastolic blood pressure, mean arterial pressure, and heart rate were recorded every 30 min during the day and every 60 min at night during a 24-h period. Linear mixed models analyses revealed that lower systolic and diastolic blood pressure and mean arterial pressure were related to giving social support. Furthermore, correlational analyses revealed that participants with a higher tendency to give social support reported greater received social support, greater self-efficacy, greater self-esteem, less depression, and less stress than participants with a lower tendency to give social support to others. Structural equation modeling was also used to test a proposed model that giving and receiving social support represent separate pathways predicting blood pressure and health. From this study, it appears that giving social support may represent a unique construct from receiving social support and may exert a unique effect on health.

  19. SY 13-3 DISTRIBUTION OF 24-H AMBULATORY BLOOD PRESSURE IN CHILDREN.

    Science.gov (United States)

    Oh, Jun

    2016-09-01

    Hypertension is a major risk factor for stroke, coronary artery disease and kidney damage in adults and children. There is a paucity of data on the long-term sequelae of persistent hypertension in children, but it is already known that children with hypertension have evidence of end organ damage and are at risk of hypertension into adulthood. The prevalence of hypertension in children is rising, most likely due to a concurrent rise in obesity rates. In children with hypertension, non-pharmacological measures are often recommended as first-line therapy, but a significant proportion of children will eventually require pharmacological treatment to reduce blood pressure, especially those with evidence of end organ damage at presentation or during follow-up. Twenty-four-hour ambulatory blood pressure monitoring (ABPM) is an essential tool in the diagnosis and therapeutic monitoring of arterial hypertension in children. In this review I will describe and discuss current methods to evaluate of BP level, the distribution of ABPM, outline available methods for BP assessment and discuss the clinical consequences of BP variability.

  20. Arterial–ventricular coupling and parameters of vascular stiffness in hypertensive patients: Role of gender

    Science.gov (United States)

    Bruno, Rosa Maria; Buralli, Simona; Barzacchi, Marta; Dal Canto, Elisa; Ghiadoni, Lorenzo; Taddei, Stefano

    2017-01-01

    Objective Non-invasive estimation of arterial–ventricular coupling has been extensively used for the evaluation of cardiovascular performance, however, a relative small amount of data is available regarding arterial–ventricular coupling and its components in hypertension. The present study was designed to investigate the relationship between left ventricular elastance, arterial elastance, parameters of vascular stiffness and the influence of gender in a population of hypertensive individuals. Methods In 102 patients, trans-thoracic cardiac ultrasound, parameters of aortic stiffness (carotid-femoral pulse wave velocity) and wave reflection (augmentation index) were recorded. Ultrasound images of common carotid arteries were acquired for the assessment of intima-media thickness as well as carotid compliance and distensibility coefficient. Results Mean age was 61 years, 32% diabetes, 56% dyslipidemia, 9% previous cardiovascular events; women (n = 32) and men were superimposable for cardiovascular risk factors prevalence. In the population, ventricular elastance was significantly correlated with arterial elastance (r = 0.887), age (r = 0.334), gender (r = −0.494), BMI (r = −0.313), augmentation index (r = 0.479) (all p arterial elastance and gender were independently associated with ventricular elastance in multiple regression models adjusted for confounding factors. Gender-specific analysis revealed that arterial elastance and augmentation index remained statistically significant associated with ventricular elastance in men (r = 0.275, p = 0.04); instead augmentation index was no longer significant (r = 0.052, p = 0.77) in the female sex. Conclusions In hypertensive patients, main determinants of ventricular elastance are arterial elastance, as an integrated index of arterial vascular load, and gender; however, pressure augmentation might play an additional role in men. PMID:28210489

  1. Stiff Neck, Torticollis, and Pseudotumor Cerebri

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2002-05-01

    Full Text Available Three prepubertal children diagnosed with pseudotumor cerebri and presenting with stiff neck and torticollis are reported from Schneider Children’s Medical Center, Sackler School of Medicine, Tel Aviv, Israel.

  2. Observed variations of monopile foundation stiffness

    DEFF Research Database (Denmark)

    Kallehave, Dan; Thilsted, C.L.; Diaz, Alberto Troya

    2015-01-01

    The soil-structure stiffness of monopile foundations for offshore wind turbines has a high impact on the fatigue loading during normal operating conditions. Thus, a robust design must consider the evolution of pile-soil stiffness over the lifetime of the wind farm. This paper present and discuss...... full-scale measurements obtained from one offshore wind turbine structure located within Horns Reef II offshore wind farm. Data are presented for a 2.5 years period and covers normal operating conditions and one larger storm event. A reduction of the pile-soil stiffness was observed during the storm...... events, followed by a complete regain to a pre-storm level when the storm subsided. In additional, no long term variations of the pile-soil stiffness was observed. The wind turbine is located in dense to very dense sand deposits....

  3. Stiff person syndrome and myasthenia gravis.

    Directory of Open Access Journals (Sweden)

    Saravanan P

    2002-01-01

    Full Text Available Association of stiff person syndrome, an immune related disorder of anterior horn cells and myasthenia gravis an endplate disorder with similar pathogenesis, is rare. This communication documents this association in the Indian literature for the first time.

  4. Vascular Stiffness in Insulin Resistance and Obesity

    Directory of Open Access Journals (Sweden)

    Guanghong eJia

    2015-08-01

    Full Text Available Obesity, insulin resistance, and type 2 diabetes are associated with a substantially increased prevalence of vascular fibrosis and stiffness, with attendant increased risk of cardiovascular and chronic kidney disease. Although the underlying mechanisms and mediators of vascular stiffness are not well understood, accumulating evidence supports the role of metabolic and immune dysregulation related to increased adiposity, activation of the renin angiotensin aldosterone system, reduced bioavailable nitric oxide, increased vascular extracellular matrix (ECM and ECM remodeling in the pathogenesis of vascular stiffness. This review will give a brief overview of the relationship between obesity, insulin resistance and increased vascular stiffness to provide a contemporary understanding of the proposed underlying mechanisms and potential therapeutic strategies.

  5. Strength and stiffness of engineering systems

    CERN Document Server

    Leckie, Frederick A

    2009-01-01

    This book on the stiffness and strength of engineering systems integrates a wide array of topics into a unified text, including plasticity, fracture, composite materials, energy approaches, and mechanics of microdevices (MEMs)..

  6. Equine wellness care in ambulatory practice.

    Science.gov (United States)

    Sandoval, Claudia; True, Claudia

    2012-04-01

    Clients want dependable veterinary care and to understand how the services will benefit and meet their horse’s needs. Wellness visits provide ambulatory practitioners with great opportunities to strengthen the doctor-client-patient bond; effective communication with clients during wellness visits, where new literature or facts can be presented, can offer opportunities for demonstrating the value of having the veterinarian maintain a primary role in disease control. The criteria for selecting vaccines, interpreting FECs, and diagnosing dental pathology require the continued need for veterinary involvement. When providing wellness services, veterinarians should discuss those services, the reasons for them, as well as the possibility of adverse reactions. In so doing, the veterinarian is able to clearly distinguish himself or herself from a technician who is merely giving a "shot." Although some of these services can be performed by clients and lay professionals, the knowledge and training that veterinarians bring to these tasks add benefits to the horse beyond the services provided. For example, by targeting treatment and conveying the goals and limitations of FECs and deworming to clients, the speed at which anthelmintic resistance occurs will be diminished, and veterinarians will regain control over equine parasite management. Additional client education, such as demonstrating dental pathology to clients and how veterinary treatment benefits their horse, will not only improve the health of the horse further but also solidify the veterinarian’s role in preventative medicine. While all components of a wellness program were not detailed here, services such as nutritional consultation, blood work, and lameness evaluation should be offered based on the practice’s equine population. With the increasing population of geriatric horses, dentistry, nutrition, blood work, and lameness should be assessed annually or biannually. Each practice has its own set of criteria

  7. Stiffness of Railway Soil-Steel Structures

    Science.gov (United States)

    Machelski, Czesław

    2015-12-01

    The considerable influence of the soil backfill properties and that of the method of compacting it on the stiffness of soil-steel structures is characteristic of the latter. The above factors (exhibiting randomness) become apparent in shell deformation measurements conducted during construction and proof test loading. A definition of soil-shell structure stiffness, calculated on the basis of shell deflection under the service load, is proposed in the paper. It is demonstrated that the stiffness is the inverse of the deflection influence function used in structural mechanics. The moving load methodology is shown to be useful for testing, since it makes it possible to map the shell deflection influence line also in the case of group loads (concentrated forces), as in bridges. The analyzed cases show that the shell's span, geometry (static scheme) and the height of earth fill influence the stiffness of the structure. The soil-steel structure's characteristic parameter in the form of stiffness k is more suitable for assessing the quality of construction works than the proposed in code geometric index ω applied to beam structures. As shown in the given examples, parameter k is more effective than stiffness parameter λ used to estimate the deformation of soil-steel structures under construction. Although the examples concern railway structures, the methodology proposed in the paper is suitable also for road bridges.

  8. Irbesartan improves arterial compliance more than lisinopril

    OpenAIRE

    2009-01-01

    Khalid Ali,1 Chakravarthi Rajkumar,1 Francesco Fantin,2 Rebekah Schiff,3 Christopher J Bulpitt31Academic Department of Geriatrics, Brighton and Sussex Medical School, Brighton, UK; 2Department of Geriatrics, University of Verona, Italy; 3Section of Geriatric Medicine, Imperial College School of Medicine, London, UKBackground: Antihypertensive agents can reduce arterial stiffness. We hypothesized that an angiotensin receptor blocker (ARB) irbesartan and an angiotensin converting enzyme inhibit...

  9. Casual and ambulatory blood pressure monitoring in children with renal scarring

    Directory of Open Access Journals (Sweden)

    Miloševski Gordana

    2005-01-01

    Full Text Available INTRODUCTION Renal scarring is the most common cause of arterial hypertension in children. High blood pressure (BP and microalbuminuria contribute to the progression of chronic renal disease. OBJECTIVE The aims of the study were: to assess BP in children with renal scarring by continuous ambulatory blood pressure measurement (ABPM in comparison to the casual method (CBP, and to determine the correlation between ambulatory blood pressure (ABP and/or casual blood pressure (CBP values and proteinuria in children with renal scarring. METHOD This forward-looking study comprised thirty-five children (26 girls and 9 boys, aged between 3-13 years, 10.4±3.9, X+SD. Blood pressure was measured using the casual method (CBP with a mercury manometer; BP was measured three times and the average was taken as a referent value. ABPM was performed using the oscillometric method with the Space Labs device, model 90207. RESULTS 45.71% of patients were classified as hypertensive by ABPM, while only 22.6% of CBP measurements were above the 95th percentile (p<0.01. "White coat hypertension" was present in 40% of the patients. Non-dipping BP alteration was detected in 37.14% of the patients. CONCLUSION Nocturnal systolic hypertension (systolic non-dipping alteration is very frequent in children with renal scarring. Nocturnal diastolic blood pressure, detectable only via ABPM, is positively correlated with proteinuria and may be an initial sign of the progression of renal scarring. ABPM is more sensitive than CBP in the evaluation of BP in children with renal scarring.

  10. Arterial structure and function in vascular ageing: are you as old as your arteries?

    Science.gov (United States)

    Thijssen, Dick H J; Carter, Sophie E; Green, Daniel J

    2016-04-15

    Advancing age may be the most potent independent predictor of future cardiovascular events, a relationship that is not fully explained by time-related changes in traditional cardiovascular risk factors. Since some arteries exhibit differential susceptibility to atherosclerosis, generalisations regarding the impact of ageing in humans may be overly simplistic, whereas in vivo assessment of arterial function and health provide direct insight. Coronary and peripheral (conduit, resistance and skin) arteries demonstrate a gradual, age-related impairment in vascular function that is likely to be related to a reduction in endothelium-derived nitric oxide bioavailability and/or increased production of vasoconstrictors (e.g. endothelin-1). Increased exposure and impaired ability for defence mechanisms to resist oxidative stress and inflammation, but also cellular senescence processes, may contribute to age-related changes in vascular function and health. Arteries also undergo structural changes as they age. Gradual thickening of the arterial wall, changes in wall content (i.e. less elastin, advanced glycation end-products) and increase in conduit artery diameter are observed with older age and occur similarly in central and peripheral arteries. These changes in structure have important interactive effects on artery function, with increases in small and large arterial stiffness representing a characteristic change with older age. Importantly, direct measures of arterial function and structure predict future cardiovascular events, independent of age or other cardiovascular risk factors. Taken together, and given the differential susceptibility of arteries to atherosclerosis in humans, direct measurement of arterial function and health may help to distinguish between biological and chronological age-related change in arterial health in humans.

  11. Ambulatory Estimation of Relative Foot Positions using Ultrasound

    NARCIS (Netherlands)

    Weenk, Dirk; Coelen, van der Michiel; Geessink, Arno A.G.; Hoek, van der Frank J.; Verstoep, Bart; Kortier, Henk G.; Meulen, van Fokke B.; Beijnum, van Bert-Jan F.; Veltink, Peter H.

    2013-01-01

    The recording of human movement is used for biomedical applications like physical therapy and sports training. Over the last few years inertial sensors have been proven to be a useful ambulatory alternative to traditional optical systems. An example of a successful application is the instrumented sh

  12. Ambulatory position and orientation tracking fusing magnetic and inertial sensing

    NARCIS (Netherlands)

    Roetenberg, Daniel; Slycke, Per J.; Veltink, Peter H.

    2007-01-01

    This paper presents the design and testing of a portable magnetic system combined with miniature inertial sensors for ambulatory 6 degrees of freedom ( DOF) human motion tracking. The magnetic system consists of three orthogonal coils, the source, fixed to the body and 3-D magnetic sensors, fixed to

  13. Screening for Pediatric Obstructive Sleep Apnea before Ambulatory Surgery

    Science.gov (United States)

    Ishman, Stacey L.; Tawfik, Kareem O.; Smith, David F.; Cheung, Kristin; Pringle, Lauren M.; Stephen, Matthew J.; Everett, Tiffany L.; Stierer, Tracey L.

    2015-01-01

    Purpose: The American Society of Anesthesia practice guidelines recommend that pediatric and adult patients who undergo ambulatory surgery be screened for obstructive sleep apnea (OSA). With this in mind, our objective was to assess the frequency of screening by anesthesia providers for the signs and symptoms of OSA in children undergoing surgery in an ambulatory setting. Methods: Prospective single-blinded observational study of anesthesia providers' preoperative interview of caregivers of consecutive patients younger than age 18 who were scheduled for ambulatory surgery. Results: One hundred one children (30 females) were identified, with a mean age of 6.9 ± 5.0 years; 54 were classified as white, 33 as black, and 14 as other. Total OSA-18 scores ranged from 18 to 97, with a mean of 33.1 ± 14.8. The mean score for adenotonsillectomy patients was higher than that for children who underwent procedures other than adenotonsillectomy. Thirty-one percent of children were screened for OSA, and snoring was the most common symptom recorded (28%). Patients who were screened for OSA were more likely to have snoring (p Tawfik KO, Smith DF, Cheung K, Pringle LM, Stephen MJ, Everett TL, Stierer TL. Screening for pediatric obstructive sleep apnea before ambulatory surgery. J Clin Sleep Med 2015;11(7):751–755. PMID:25902820

  14. Diverging effects of diabetes mellitus in patients with peripheral artery disease and abdominal aortic aneurysm and the role of advanced glycation end products:: ARTERY study. Protocol for a multicenter cross-sectional study

    OpenAIRE

    Vos, L.C. de; Boersema, J.; Hillebrands, J. L.; Schalkwijk, C. G.; Meerwaldt, R.; Breek, J.C.; Smit, A. J.; C. J. Zeebregts; Lefrandt, J.D.

    2016-01-01

    Introduction: Diabetes mellitus is a well-defined risk factor for peripheral artery disease (PAD), but protects against the development and growth of abdominal aortic aneurysm (AAA). Diabetes mellitus is associated with arterial stiffening and peripheral arterial media sclerosis. Advanced glycation end products (AGEs) are increased in diabetes mellitus and cardiovascular disease. AGEs are known to form cross-links between proteins and are associated with arterial stiffness. Whether AGEs contr...

  15. The stable stiffness triangle - drained sand during deformation cycles

    DEFF Research Database (Denmark)

    Sabaliauskas, Tomas; Ibsen, Lars Bo

    2017-01-01

    Cyclic, drained sand stiffness was observed using the Danish triaxial appa- ratus. New, deformation dependant soil property (the stable stiffness triangle) was detected. Using the the stable stiffness triangle, secant stiffness of drained sand was plausible to predict (and control) even during ir...

  16. Waves in geomaterials exhibiting negative stiffness behaviour

    Science.gov (United States)

    Esin, Maxim; Dyskin, Arcady; Pasternak, Elena

    2016-04-01

    Negative stiffness denotes the type of material behaviour when the force applied to the body decreases the body's deformation increases. Some geomaterials, for instance, rocks, demonstrate behaviour of this type at certain loads: during the compression tests the loading curves exhibit descending branch (post-peak softening). One of the possible mechanisms of the negative stiffness appearance in geomaterials is rotation of non-spherical grains. It is important to emphasize that in this case the descending branch may be reversible given that the testing machine is stiff enough (in general case it means an importance of boundary conditions). Existence of geomaterials with a negative modulus associated with rotations may have significant importance. In particular, important is understanding of the wave propagation in such materials. We study the stability of geomaterials with negative stiffness inclusions and wave propagation in it using two approaches: Cosserat continuum and discrete mass-spring models. In both cases we consider the rotational degrees of freedom in addition to the conventional translational ones. We show that despite non positiveness of the energy the materials with negative stiffness elements can be stable if certain conditions are met. In the case of Cosserat continuum the Cosserat shear modulus (the modulus relating the non-symmetrical part of shear stress and internal rotations) is allowed to assume negative values as long as its value does not exceed the value of the standard (positive) shear modulus. In the case of discrete mass-spring systems (with translational and rotational springs) the concentration of negative stiffness springs and the absolute values of negative spring stiffness are limited. The critical concentration when the system loses stability and the amplitude of the oscillations tends to infinity is equal to 1/2 and 3/5 for two- and three-dimensional cases respectively.

  17. Carotid artery surgery

    Science.gov (United States)

    Carotid endarterectomy; CAS surgery; Carotid artery stenosis - surgery; Endarterectomy - carotid artery ... through the catheter around the blocked area during surgery. Your carotid artery is opened. The surgeon removes ...

  18. The ten successful elements of an ambulatory care center.

    Science.gov (United States)

    Watkins, G

    1997-01-01

    Experts in healthcare predict that in the future, over 80% of all care will be provided either in the home or ambulatory care centers. How radiology facilities position themselves for this shifting market is critical to their long-term success, even though it appears there are endless opportunities for providing care in this atmosphere. The ten most critical elements that healthcare providers must address to ensure their preparedness are discussed. Location is critical, particularly since patients no longer want to travel to regional medical centers. The most aggressive providers are building local care centers to serve specific populations. Ambulatory care centers should project a high tech, high touch atmosphere. Patient comfort and the appeal of the overall environment must be considered. Centers need to focus on their customers' needs in multiple areas of care. A quick and easy registration process, providing dressing gowns in patient areas, clear billing functions--these are all important areas that centers should develop. Physicians practicing in the ambulatory care center are key to its overall success and can set the tone for all staff members. Staff members must be friendly and professional in their work with patients. The hours offered by the center must meet the needs of its client base, perhaps by offering evening and weekend appointments. Keeping appointments on schedule is critical if a center wants satisfied customers. It's important to identify the target before developing your marketing plan. Where do your referrals come from? Look to such sources as referring physicians, managed care plans and patients themselves. Careful billing is critical for survival in the ambulatory care world. Costs are important and systems that can track cost per exam are useful. Know your bottom line. Service remains the central focus of all successful ambulatory care center functions.

  19. Pharmacological treatment of ambulatory schizophrenic patients in Belgium

    Directory of Open Access Journals (Sweden)

    Reginster J-Y

    2006-05-01

    Full Text Available Abstract Background the objective of this study was twofold: 1 Describe the use of antipsychotic treatments in ambulatory patients suffering from schizophrenia in Belgium. 2 Evaluate to which extend antipsychotic treatment prescribing patterns are in accordance with published treatment guidelines. Method A cross-sectional survey was carried out in 16 Belgian hospitals selected from a sample of 67 hospitals. The hospitals were equally distributed between the north and south part of the country and were representative of Belgian practice. During 2 months, participating psychiatrists were asked to record the medication use as well as demographic parameters of all consecutive ambulatory patients seen at their consultation or attending a day-hospital. Data concerning 1000 ambulatory patients with schizophrenia or schizoaffective disorder were collected. Results In Belgium, the use of atypical antipsychotics is frequent (69% in ambulatory patients with schizophrenia. In the overall sample, 73% receive only one antipsychotic drug. The majority of patients are treated with drugs of only one antipsychotic drug group, either first- typical (29.8% or second-generation, atypical antipsychotics (53.2%. 15.8% of patients combine different types of antipsychotics. Antipsychotic dosing is adequate for the majority of patients but about one fifth receives a higher than recommended dose as per package inserts. Polypharmacy remains within reasonable limits. The use of concomitant medication varies according the antipsychotic treatment: patients who take second-generation antipsychotics only, receive the least additional drugs. Conclusion Atypical antipsychotics appear to be the first line treatment for schizophrenic psychosis. Psychiatrists working with ambulatory patients are well aware of treatment guidelines and follow them quite adequately.

  20. Characteristics of ambulatory anticoagulant adverse drug events: a descriptive study

    Directory of Open Access Journals (Sweden)

    Eckstrand Julie

    2010-02-01

    Full Text Available Abstract Background Despite the high frequency with which adverse drug events (ADEs occur in outpatient settings, detailed information regarding these events remains limited. Anticoagulant drugs are associated with increased safety concerns and are commonly involved in outpatient ADEs. We therefore sought to evaluate ambulatory anticoagulation ADEs and the patient population in which they occurred within the Duke University Health System (Durham, NC, USA. Methods A retrospective chart review of ambulatory warfarin-related ADEs was conducted. An automated trigger surveillance system identified eligible events in ambulatory patients admitted with an International Normalized Ratio (INR >3 and administration of vitamin K. Event and patient characteristics were evaluated, and quality/process improvement strategies for ambulatory anticoagulation management are described. Results A total of 169 events in 167 patients were identified from December 1, 2006-June 30, 2008 and included in the study. A median supratherapeutic INR of 6.1 was noted, and roughly half of all events (52.1% were associated with a bleed. Nearly 74% of events resulted in a need for fresh frozen plasma; 64.8% of bleeds were classified as major. A total of 59.2% of events were at least partially responsible for hospital admission. Median patient age was 68 y (range 36-95 y with 24.9% initiating therapy within 3 months prior to the event. Of events with a prior documented patient visit (n = 157, 73.2% were seen at a Duke clinic or hospital within the previous month. Almost 80% of these patients had anticoagulation therapy addressed, but only 60.0% had a follow-up plan documented in the electronic note. Conclusions Ambulatory warfarin-related ADEs have significant patient and healthcare utilization consequences in the form of bleeding events and associated hospital admissions. Recommendations for improvement in anticoagulation management include use of information technology to assist

  1. Single motor–variable stiffness actuator using bistable switching mechanisms for independent motion and stiffness control

    NARCIS (Netherlands)

    Groothuis, S.S.; Carloni, R.; Stramigioli, S.

    2016-01-01

    This paper presents a proof of concept of a variable stiffness actuator (VSA) that uses only one (high power) input motor. In general, VSAs use two (high power) motors to be able to control both the output position and the output stiffness, which possibly results in a heavy, and bulky system. In thi

  2. Relationship Between Ambulatory Blood Pressure Parameters and Pulse Wave Velocity in Prehypertensive Patients%血压正常高值者动脉僵硬度与动态血压参数的关系

    Institute of Scientific and Technical Information of China (English)

    胡小亮; 路方红; 刘振东; 赵颖馨; 孙尚文; 王舒健; 潘慧; 李俊

    2012-01-01

    Aim To investigate the relationship between ambulatory blood pressure parameters and arterial stiffness in prehypertensive patients. Methods According to their blood pressure level, 204 individuals were divided into three groups: namely normotensive controls ( n = 63 ) , prehypertensive participants ( n = 74 ) and hypertensive patients ( n = 67) . The 24 h ambulatory blood pressure monitoring was used to record 24 h systolic blood pressure (24h SBP) , 24 h diastolic blood pressure (24h DBP) , daytime systolic blood pressure (dSBP) , daytime diastolic blood pressure (dDBP) , nighttime systolic blood pressure (nSBP) , nighttime diastolic blood pressure (nDBP) , 24 h pulse pressure (24h PP) , daytime pulse pressure ( dPP) and nighttime pulse pressure ( nPP) . Carotid-radial pulse wave velocity ( crPWV) was obtained by Complior device. Results 24h SBP, 24h DBP, dSBP, dDBP, nSBP, 24h PP, dPP and nPP were higher in prehypertensive than those in normotensives, but lower in hypertensives ( P < 0. 05 or P < 0. 01) . The crPWV in prehy-pertensives was 9. 67 ± 1. 12 m/s, which was higher than that in normotensives (8. 27 ±0. 99 m/s) , but was lower in hypertensives (10. 55 ± 1. 71 m/s) . Multiple linear regression analysis showed that 24h SBP, 24h PP and nSBP were risk factors for crPWV ( B = 0. 385 , 0351 and 0. 247; all P < 0. 05 ) . Conclusion Arterial stiffness had been increased inprehypertensives. 24h SBP, 24h PP and nSBP are the important influencing factors of arterial stiffness.%目的 探讨血压正常高值者动脉僵硬度与动态血压参数的关系.方法 选择理想血压者63例,血压正常高值者74例,高血压者67例.监测所有入选者24h动态血压,应用脉搏波传导速度测定仪测定颈动脉-桡动脉脉搏波传导速度.结果 血压正常高值组24 h收缩压、24 h舒张压、白昼收缩压、白昼舒张压、夜间收缩压、24 h脉压、白昼脉压及夜间脉压均高于理想血压组,低于高血压组(P<0.05或P<0

  3. Hepatic Hemodynamics and Elevation of Liver Stiffness as Possible Predictive Markers of Late-onset Hepatic Failure.

    Science.gov (United States)

    Kakisaka, Keisuke; Kuroda, Hidekatsu; Abe, Tamami; Suzuki, Yuji; Yoshida, Yuichi; Kataoka, Kojiro; Miyamoto, Yasuhiro; Ishida, Kazuyuki; Takikawa, Yasuhiro

    2016-01-01

    A 52-year-old Japanese woman admitted to our hospital for the treatment of liver dysfunction due to an undetermined cause developed disorientation on the 58th hospital day and was diagnosed with late-onset liver failure. Abdominal ultrasound examinations were performed several times from the admission. Before the disorientation appeared, the results of the examinations revealed that the portal flow decreased, after which the hepatic arterial flow increased and the degree of liver stiffness became elevated. Although the pathophysiology of these changes remains unclear, hemodynamic changes and elevation of liver stiffness might be predictive markers of severe liver tissue damage.

  4. [Stiff-person syndrome and related autoantibodies].

    Science.gov (United States)

    Tomioka, Ryo; Tanaka, Keiko

    2013-04-01

    Central nervous system hyperexcitability disorders, known as stiff-man/person syndrome (SPS), are thought to be related to the regulatory disturbance of inhibitory synaptic transmission of motor neurons in the brainstem and spinal cord. SPS is characterized by stiffness and spasms of the axis and limbs and is divided into two clinical subgroups: classic SPS, which affects the lumbar, trunk, and proximal limb muscles, and SPS-plus syndrome. The latter comprises (1) the stiff-limb subtype, in which symptom is limited to the lower limbs; (2) jerking stiff-man syndrome, characterized by chronically progressive stiffness and myoclonus; and (3) acute-onset and progressive encephalomyelitis with rigidity and myoclonus. Almost 80% of patients with classic SPS harbor autoantibodies against glutamic acid decarboxylase 65 (GAD65). In approximately 30-40% of patients, SPS accompanies type I diabetes, and anti-GAD65 antibodies are detected frequently in type I diabetes. However, the antibody-recognizing epitopes might be different between SPS and diabetes. Other autoantibodies against glycine receptor α1 (12% of patients with SPS) and GABA(A)-receptor associated protein (70% of patients with SPS) have been reported. In paraneoplastic SPS, anti-amphiphysin antibodies have been shown in patients with breast cancer or small cell lung cancer. One case of mediastinal tumor with anti-gephyrin antibodies has also been reported. However, the roles of these autoantibodies in the pathomechanisms of SPS have not yet been elucidated.

  5. Big Bang nucleosynthesis with a stiff fluid

    CERN Document Server

    Dutta, Sourish

    2010-01-01

    Models that lead to a cosmological stiff fluid component, with a density $\\rho_S$ that scales as $a^{-6}$, where $a$ is the scale factor, have been proposed recently in a variety of contexts. We calculate numerically the effect of such a stiff fluid on the primordial element abundances. Because the stiff fluid energy density decreases with the scale factor more rapidly than radiation, it produces a relatively larger change in the primordial helium-4 abundance than in the other element abundances, relative to the changes produced by an additional radiation component. We show that the helium-4 abundance varies linearly with the density of the stiff fluid at a fixed fiducial temperature. Taking $\\rho_{S10}$ and $\\rho_{R10}$ to be the stiff fluid energy density and the standard density in relativistic particles, respectively, at $T = 10$ MeV, we find that the change in the primordial helium abundance is well-fit by $\\Delta Y_p = 0.00024(\\rho_{S10}/\\rho_{R10})$. The changes in the helium-4 abundance produced by ad...

  6. Torso flexion modulates stiffness and reflex response.

    Science.gov (United States)

    Granata, K P; Rogers, E

    2007-08-01

    Neuromuscular factors that contribute to spinal stability include trunk stiffness from passive and active tissues as well as active feedback from reflex response in the paraspinal muscles. Trunk flexion postures are a recognized risk factor for occupational low-back pain and may influence these stabilizing control factors. Sixteen healthy adult subjects participated in an experiment to record trunk stiffness and paraspinal muscle reflex gain during voluntary isometric trunk extension exertions. The protocol was designed to achieve trunk flexion without concomitant influences of external gravitational moment, i.e., decouple the effects of trunk flexion posture from trunk moment. Systems identification analyses identified reflex gain by quantifying the relation between applied force disturbances and time-dependent EMG response in the lumbar paraspinal muscles. Trunk stiffness was characterized from a second order model describing the dynamic relation between the force disturbances versus the kinematic response of the torso. Trunk stiffness increased significantly with flexion angle and exertion level. This was attributed to passive tissue contributions to stiffness. Reflex gain declined significantly with trunk flexion angle but increased with exertion level. These trends were attributed to correlated changes in baseline EMG recruitment in the lumbar paraspinal muscles. Female subjects demonstrated greater reflex gain than males and the decline in reflex gain with flexion angle was greater in females than in males. Results reveal that torso flexion influences neuromuscular factors that control spinal stability and suggest that posture may contribute to the risk of instability injury.

  7. A Novel Variable Stiffness Mechanism Capable of an Infinite Stiffness Range and Unlimited Decoupled Output Motion

    Directory of Open Access Journals (Sweden)

    Stefan Groothuis

    2014-06-01

    Full Text Available In this paper, a novel variable stiffness mechanism is presented, which is capable of achieving an output stiffness with infinite range and an unlimited output motion, i.e., the mechanism output is completely decoupled from the rotor motion, in the zero stiffness configuration. The mechanism makes use of leaf springs, which are engaged at different positions by means of two movable supports, to realize the variable output stiffness. The Euler–Bernoulli leaf spring model is derived and validated through experimental data. By shaping the leaf springs, it is shown that the stiffness characteristic of the mechanism can be changed to fulfill different application requirements. Alternative designs can achieve the same behavior with only one leaf spring and one movable support pin.

  8. Electrochemical stiffness in lithium-ion batteries

    Science.gov (United States)

    Tavassol, Hadi; Jones, Elizabeth M. C.; Sottos, Nancy R.; Gewirth, Andrew A.

    2016-11-01

    Although lithium-ion batteries are ubiquitous in portable electronics, increased charge rate and discharge power are required for more demanding applications such as electric vehicles. The high-rate exchange of lithium ions required for more power and faster charging generates significant stresses and strains in the electrodes that ultimately lead to performance degradation. To date, electrochemically induced stresses and strains in battery electrodes have been studied only individually. Here, a new technique is developed to probe the chemomechanical response of electrodes by calculating the electrochemical stiffness via coordinated in situ stress and strain measurements. We show that dramatic changes in electrochemical stiffness occur due to the formation of different graphite-lithium intercalation compounds during cycling. Our analysis reveals that stress scales proportionally with the lithiation/delithiation rate and strain scales proportionally with capacity (and inversely with rate). Electrochemical stiffness measurements provide new insights into the origin of rate-dependent chemomechanical degradation and the evaluation of advanced battery electrodes.

  9. Dynamic stiffness model of spherical parallel robots

    Science.gov (United States)

    Cammarata, Alessandro; Caliò, Ivo; D`Urso, Domenico; Greco, Annalisa; Lacagnina, Michele; Fichera, Gabriele

    2016-12-01

    A novel approach to study the elastodynamics of Spherical Parallel Robots is described through an exact dynamic model. Timoshenko arches are used to simulate flexible curved links while the base and mobile platforms are modelled as rigid bodies. Spatial joints are inherently included into the model without Lagrangian multipliers. At first, the equivalent dynamic stiffness matrix of each leg, made up of curved links joined by spatial joints, is derived; then these matrices are assembled to obtain the Global Dynamic Stiffness Matrix of the robot at a given pose. Actuator stiffness is also included into the model to verify its influence on vibrations and modes. The latter are found by applying the Wittrick-Williams algorithm. Finally, numerical simulations and direct comparison to commercial FE results are used to validate the proposed model.

  10. Coronary artery fistula

    Science.gov (United States)

    Congenital heart defect - coronary artery fistula; Birth defect heart - coronary artery fistula ... A coronary artery fistula is often congenital, meaning that it is present at birth. It generally occurs when one of the coronary arteries ...

  11. Consumption of a Polyphenol-Rich Grape-Wine Extract Lowers Ambulatory Blood Pressure in Mildly Hypertensive Subjects

    Directory of Open Access Journals (Sweden)

    Richard Draijer

    2015-04-01

    Full Text Available Polyphenols in grape and wine have been suggested to contribute to the cardiovascular health benefits of the Mediterranean lifestyle. The reported effects of grape products on blood pressure (BP remain, however, equivocal. In a double-blind placebo controlled crossover study, the effect of two grape extracts on BP and vascular function was assessed in 60 untreated, mildly hypertensive subjects after four weeks intervention. Both extracts (grape-red wine and grape alone had high concentrations of anthocyanins and flavonols, but the grape alone was relatively poor in catechins and procyanidins. Parameters measured included ambulatory and office BP, flow-mediated vasodilation, arterial distensibility, platelet function and plasma lipoproteins. Results showed that 24-hour ambulatory systolic/diastolic BPs were significantly lower in the grape-wine extract intervention (135.9 ± 1.3/84.7 ± 0.8 mmHg; mean ± SEM compared to placebo (138.9 ± 1.3/86.6 ± 1.2 mmHg, predominantly during daytime. Plasma concentrations of the vasoconstrictor endothelin-1 decreased by 10%, but other measures of vascular function were not affected. Grape juice extract alone had no effect on BP or any measures of vascular function. Polyphenol-rich food products, and may be specifically catechins and procyanidins, may thus help sustain a healthy BP and contribute to the healthy Mediterranean lifestyle.

  12. Consumption of a polyphenol-rich grape-wine extract lowers ambulatory blood pressure in mildly hypertensive subjects.

    Science.gov (United States)

    Draijer, Richard; de Graaf, Young; Slettenaar, Marieke; de Groot, Eric; Wright, Chris I

    2015-04-30

    Polyphenols in grape and wine have been suggested to contribute to the cardiovascular health benefits of the Mediterranean lifestyle. The reported effects of grape products on blood pressure (BP) remain, however, equivocal. In a double-blind placebo controlled crossover study, the effect of two grape extracts on BP and vascular function was assessed in 60 untreated, mildly hypertensive subjects after four weeks intervention. Both extracts (grape-red wine and grape alone) had high concentrations of anthocyanins and flavonols, but the grape alone was relatively poor in catechins and procyanidins. Parameters measured included ambulatory and office BP, flow-mediated vasodilation, arterial distensibility, platelet function and plasma lipoproteins. Results showed that 24-hour ambulatory systolic/diastolic BPs were significantly lower in the grape-wine extract intervention (135.9 ± 1.3/84.7 ± 0.8 mmHg; mean ± SEM) compared to placebo (138.9 ± 1.3/86.6 ± 1.2 mmHg), predominantly during daytime. Plasma concentrations of the vasoconstrictor endothelin-1 decreased by 10%, but other measures of vascular function were not affected. Grape juice extract alone had no effect on BP or any measures of vascular function. Polyphenol-rich food products, and may be specifically catechins and procyanidins, may thus help sustain a healthy BP and contribute to the healthy Mediterranean lifestyle.

  13. Variable stiffness and damping magnetorheological isolator

    Institute of Scientific and Technical Information of China (English)

    Yang ZHOU; Xingyu WANG; Xianzhou ZHANG; Weihua LI

    2009-01-01

    This paper presents the development and characterization of a magnetorheological (MR) fluid-based variable stiffness and damping isolator. The prototype of the MR fluid isolator is fabricated, and its dynamic behavior is measured under various applied magnetic fields. The parameters of the model under various magnetic fields are identified, and the dynamic perfor-mance of the isolator is evaluated in simulation. Experi-mental results indicate that both the stiffness and damping capability of the developed MR isolator can be controlled by an external magnetic field.

  14. Experimental investigation of the influence of the aortic stiffness on hemodynamics in the ascending aorta.

    Science.gov (United States)

    Gülan, Utku; Lüthi, Beat; Holzner, Markus; Liberzon, Alex; Tsinober, Arkady; Kinzelbach, Wolfgang

    2014-11-01

    A three-dimensional (3-D) pulsatile aortic flow in a human ascending aorta is studied to investigate the effect of the aortic stiffness on the flow field and turbulent fluctuating velocities in the ascending aorta. A nonintrusive optical measurement technique, 3-D particle tracking velocimetry (3D-PTV), has been applied to anatomically accurate phantoms under clinically realistic conditions. A compliant silicon phantom was used to mimic the healthy aorta, and a rigid model was used to imitate the pathological case that appears in aortas for example as a result of aging. The realistic models are transparent which allows optical access to the investigation domain, and the index of refraction was matched to avoid optical distortions. Our results revealed that the aortic stiffness leads to an increase in systolic velocity and a decrease in the Windkessel effect, which is associated with the diastolic blood pressure. Furthermore, we found that the turbulent kinetic energy is about an order of magnitude higher for the rigid aorta, that is, an increase in aortic stiffness increases the magnitude of turbulent fluctuating velocities. The spatial distribution of the flow velocity showed that the flow is more organized and coherent spiraling patterns develop for the compliant aorta which helps to dampen the influence of disturbed flow. Finally, we observed higher Lagrangian acceleration and hence higher instantaneous forces acting on blood particles in the stiff case which implies that aging and hence arterial stiffening provokes distinctive alterations in blood flow, and these alterations may cause pathological symptoms in the cardiovascular system.

  15. Modulation of fixation stiffness from flexible to stiff in a rat model of bone healing.

    Science.gov (United States)

    Bartnikowski, Nicole; Claes, Lutz E; Koval, Lidia; Glatt, Vaida; Bindl, Ronny; Steck, Roland; Ignatius, Anita; Schuetz, Michael A; Epari, Devakara R

    2016-11-14

    Background and purpose - Constant fixator stiffness for the duration of healing may not provide suitable mechanical conditions for all stages of bone repair. We therefore investigated the influence of stiffening fixation on callus stiffness and morphology in a rat diaphyseal osteotomy model to determine whether healing time was shortened and callus stiffness increased through modulation of fixation from flexible to stiff. Material and methods - An external unilateral fixator was applied to the osteotomized femur and stiffened by decreasing the offset of the inner fixator bar at 3, 7, 14, and 21 days after operation. After 5 weeks, the rats were killed and healing was evaluated with mechanical, histological, and microcomputed tomography methods. Constant fixation stiffness control groups with either stiff or flexible fixation were included for comparison. Results - The callus stiffness of the stiff group and all 4 experimental groups was greater than in the flexible group. The callus of the flexible group was larger but contained a higher proportion of unmineralized tissue and cartilage. The stiff and modulated groups (3, 7, 14, and 21 days) all showed bony bridging at 5 weeks, as well as signs of callus remodeling. Stiffening fixation at 7 and 14 days after osteotomy produced the highest degree of callus bridging. Bone mineral density in the fracture gap was highest in animals in which the fixation was stiffened after 14 days. Interpretation - The predicted benefit of a large robust callus formed through early flexible fixation could not be shown, but the benefits of stabilizing a flexible construct to achieve timely healing were demonstrated at all time points.

  16. Cognitive assessment on elderly people under ambulatory care

    Directory of Open Access Journals (Sweden)

    Bruna Zortea

    2015-04-01

    Full Text Available Objective: to evaluate the cognitive state of elderly people under ambulatory care and investigating the connection between such cognitive state and sociodemographic variables, health conditions, number of and adhesion to medicine. Methods: transversal, exploratory, and descriptive study, with a quantitative approach, realized with 107 elderly people under ambulatory care in a university hospital in southern Brazil, in november, 2013. The following variables were used: gender, age, civil status, income, schooling, occupation, preexisting noncommunicable diseases, number and type of prescribed medications, adhesion, mini-mental state examination score, and cognitive status. Data was analyzed through inferential and descriptive statistics. Results: the prevalence of cognitive deficit was of 42.1% and had a statistically significant connection to schooling, income, civil status, hypertension, and cardiopathy. Conclusion: nurses can intervene to avoid the increase of cognitive deficit through an assessment of the elderly person, directed to facilitative strategies to soften this deficit.

  17. State stiffness parameters of the vascular wall in hypertensive patients complex therapy cytoprotector and sartans

    Directory of Open Access Journals (Sweden)

    V. P. Mikhin

    2015-01-01

    Full Text Available A randomized study of the state of stiffness parameters arteries wall (CAVI — cardio-ankle vascular index, AI (augmentation index PEP (duration of the voltage of the left ventricle using «VaSera-1000» («Fukuda Denshi», Japan in primary hypertension patients (80 not treated with systemic antihypertensive therapy. The effect of long-term (3 months was be marketed. Losartan combined with Mexicor 300mg/day or mildronate 1000 mg/day for the specified parameters. It sets the initial reduction the properties of the arterial wall in patients with hypertension, in contrast to healthy individuals. Mexicor or mildronat accompanied by improvement east-cal properties of the arterial wall, reducing CAVI and AI in 3 months on 9.4% and 8.9%, 14.9% and 15.4%, respectively. In the control group-term change CAVI and AI no. Mexicor led to a more pronounced increase in PEP, than mildronate, respectively, on 23.7% and 18.9%. Losartan monotherapy results in a less pronounced decrease in the stiffness of the vessel wall.

  18. Plant fibre composites - porosity and stiffness

    DEFF Research Database (Denmark)

    Madsen, Bo; Thygesen, Anders; Lilholt, Hans

    2009-01-01

    Plant fibre composites contain typically a relatively large amount of porosity which influences their performance. A model, based on a modified rule of mixtures, is presented to include the influence of porosity on the composite stiffness. The model integrates the volumetric composition of the co......Plant fibre composites contain typically a relatively large amount of porosity which influences their performance. A model, based on a modified rule of mixtures, is presented to include the influence of porosity on the composite stiffness. The model integrates the volumetric composition...... of the composites with their mechanical properties. The fibre weight fraction is used as an independent parameter to calculate the complete volumetric composition. A maximum obtainable stiffness of the composites is calculated at a certain transition fibre weight fraction, which is characterised by a best possible...... combination of high fibre volume fraction and low porosity. The model is validated with experimental data from the literature on several types of composites. A stiffness diagram is presented to demonstrate that the calculations can be used for tailoring and design of composites with a given profile...

  19. [Anaesthetic management of Stiff Man syndrome].

    Science.gov (United States)

    Marín, T; Hernando, D; Kinast, N; Churruca, I; Sabate, S

    2015-04-01

    Stiff Man syndrome or stiff-person syndrome is a rare autoimmune disorder. It is characterized by increased axial muscular tone and limb musculature, and painful spasms triggered by stimulus. The case is presented of a 44-year-old man with stiff-person syndrome undergoing an injection of botulinum toxin in the urethral sphincter under sedation. Before induction, all the surgical team were ready in order to minimise the anaesthetic time. The patient was monitored by continuous ECG, SpO2 and non-invasive blood pressure. He was induced with fractional dose of propofol 150 mg, fentanyl 50 μg and midazolam 1mg. Despite careful titration, the patient had an O2 saturation level of 90%,which was resolved by manual ventilation. There was no muscle rigidity or spasm during the operation. Post-operative recovery was uneventful and the patient was discharged 2 days later. A review of other cases is presented. The anaesthetic concern in patients with stiff-person syndrome is the interaction between the anaesthetic agents, the preoperative medication, and the GABA system. For a safe anaesthetic management, total intravenous anaesthesia is recommended instead of inhalation anaesthetics, as well as the close monitoring of the respiratory function and the application of the electrical nerve stimulator when neuromuscular blockers are used.

  20. Stiff directed lines in random media.

    Science.gov (United States)

    Boltz, Horst-Holger; Kierfeld, Jan

    2013-07-01

    We investigate the localization of stiff directed lines with bending energy by a short-range random potential. We apply perturbative arguments, Flory scaling arguments, a variational replica calculation, and functional renormalization to show that a stiff directed line in 1+d dimensions undergoes a localization transition with increasing disorder for d>2/3. We demonstrate that this transition is accessible by numerical transfer matrix calculations in 1+1 dimensions and analyze the properties of the disorder-dominated phase in detail. On the basis of the two-replica problem, we propose a relation between the localization of stiff directed lines in 1+d dimensions and of directed lines under tension in 1+3d dimensions, which is strongly supported by identical free-energy distributions. This shows that pair interactions in the replicated Hamiltonian determine the nature of directed line localization transitions with consequences for the critical behavior of the Kardar-Parisi-Zhang equation. We support the proposed relation to directed lines via multifractal analysis, revealing an analogous Anderson transition-like scenario and a matching correlation length exponent. Furthermore, we quantify how the persistence length of the stiff directed line is reduced by disorder.

  1. Dynamic stiffness of horizontally vibrating suction caissons

    DEFF Research Database (Denmark)

    Latini, Chiara; Zania, Varvara; Cisternino, Michele

    2016-01-01

    to existing analytical solutions suggested for piles. Relatively good agreement has been achieved comparing the numerical results with the analytical solutions. Then, the effect of the soil layer shear wave velocity on the dynamic stiffness coefficients is analysed. The results have indicated that increasing...

  2. Influence of footings stiffness on punching resistance

    Directory of Open Access Journals (Sweden)

    Ĺudovít Fillo

    2016-03-01

    Full Text Available The presented paper brings new aspects of punching resistance due to influence of footing stiffness and consequential ground stresses distribution. Diagrams of design load versus effective depth were created coming from new design criteria which depend on the maximum punching resistance defined from shear-bending failure and on the maximum punching resistance defined from crushing of concrete struts.

  3. Improved Stiff ODE Solvers for Combustion CFD

    Science.gov (United States)

    Imren, A.; Haworth, D. C.

    2016-11-01

    Increasingly large chemical mechanisms are needed to predict autoignition, heat release and pollutant emissions in computational fluid dynamics (CFD) simulations of in-cylinder processes in compression-ignition engines and other applications. Calculation of chemical source terms usually dominates the computational effort, and several strategies have been proposed to reduce the high computational cost associated with realistic chemistry in CFD. Central to most strategies is a stiff ordinary differential equation (ODE) solver to compute the change in composition due to chemical reactions over a computational time step. Most work to date on stiff ODE solvers for computational combustion has focused on backward differential formula (BDF) methods, and has not explicitly considered the implications of how the stiff ODE solver couples with the CFD algorithm. In this work, a fresh look at stiff ODE solvers is taken that includes how the solver is integrated into a turbulent combustion CFD code, and the advantages of extrapolation-based solvers in this regard are demonstrated. Benefits in CPU time and accuracy are demonstrated for homogeneous systems and compression-ignition engines, for chemical mechanisms that range in size from fewer than 50 to more than 7,000 species.

  4. Measurement and Treatment of Passive Muscle Stiffness

    DEFF Research Database (Denmark)

    Kirk, Henrik

    This PhD thesis is based on research conducted at the University of Copenhagen and Helene Elsass Center from 2012 to 2015. Measurements and treatment of passive muscle stiffness in people with cerebral palsy (CP) comprise the focus of the thesis. The thesis summarizes the results from four studies...

  5. Monitoring the Bending Stiffness of DNA

    Science.gov (United States)

    Yuan, Chongli; Lou, Xiongwen; Rhoades, Elizabeth; Chen, Huimin; Archer, Lynden

    2007-03-01

    In eukaryotic cells, the accessibility of genomic sequences provides an inherent regulation mechanism for gene expression through variations in bending stiffness encoded by the nucleic acid sequence. Cyclization of dsDNA is the prevailing method for determining DNA bending stiffness. Recent cyclization data for short dsDNA raises several fundamental questions about the soundness of the cyclization method, particularly in cases where the probability of highly bent DNA conformations is low. We herein evaluate the role of T4 DNA ligase in the cyclization reaction by inserting an environmental sensitive base analogue, 2-amino purine, to the DNA molecule. By monitoring the 2-AP fluorescence under standard cyclization conditions, it is found that in addition to trapping highly-bent cyclic DNA conformations, T4 DNA ligase enhances the apparent base pair flip out rate, thus exaggerating the measured flexibility. This result is further confirmed using fluorescence anisotropy experiments. We show that fluorescence resonance energy transfer (FRET) measurements on suitably labeled dsDNA provides an alternative approach for quantifying the bending stiffness of short fragments. DNA bending stiffness results obtained using FRET are compared with literature values.

  6. Non-singular inhomogeneous stiff fluid cosmology

    CERN Document Server

    Fernández-Jambrina, L

    2009-01-01

    In this talk we show a stiff fluid solution of the Einstein equations for a cylindrically symmetric spacetime. The main features of this metric are that it is non-separable in comoving coordinates for the congruence of the worldlineS of the fluid and that it yields regular curvature invariants.

  7. [The ambulatory polyclinic institutions in closed administrative territorial municipality].

    Science.gov (United States)

    Fomin, E P

    2014-01-01

    The article presents the results characterizing functioning of ambulatory polyclinic institutions included into medical sanitary unit of closed administrative territorial municipality of lesser towns. The study established the resource support of staff and full-time positions of physician and paramedical personnel, dynamics of indicators from 2005 to 2013, coverage of population of able-bodied age with preventive and target medical examinations for syphilis and tuberculosis. The progression of contingents under dispensary registration was determined.

  8. Redesigning ambulatory care business processes supporting clinical care delivery.

    Science.gov (United States)

    Patterson, C; Sinkewich, M; Short, J; Callas, E

    1997-04-01

    The first step in redesigning the health care delivery process for ambulatory care begins with the patient and the business processes that support the patient. Patient-related business processes include patient access, service documentation, billing, follow-up, collection, and payment. Access is the portal to the clinical delivery and care management process. Service documentation, charge capture, and payment and collection are supporting processes to care delivery. Realigned provider networks now demand realigned patient business services to provide their members/customers/patients with improved service delivery at less cost. Purchaser mandates for cost containment, health maintenance, and enhanced quality of care have created an environment where every aspect of the delivery system, especially ambulatory care, is being judged. Business processes supporting the outpatient are therefore being reexamined for better efficiency and customer satisfaction. Many health care systems have made major investments in their ambulatory care environment, but have pursued traditional supporting business practices--such as multiple access points, lack of integrated patient appointment scheduling and registration, and multiple patient bills. These are areas that are appropriate for redesign efforts--all with the customer's needs and convenience in mind. Similarly, setting unrealistic expectations, underestimating the effort required, and ignoring the human elements of a patient-focused business service redesign effort can sabotage the very sound reasons for executing such an endeavor. Pitfalls can be avoided if a structured methodology, coupled with a change management process, are employed. Deloitte & Touche Consulting Group has been involved in several major efforts, all with ambulatory care settings to assist with the redesign of their business practices to consider the patient as the driver, instead of the institution providing the care.

  9. Biomechanical investigation of ambulatory training in patients with acetabular dysplasia.

    Science.gov (United States)

    Kanai, Akira; Kiyama, Takahiro; Genda, Eiichi; Suzuki, Yasuo

    2008-07-01

    The purpose of this study was to investigate the effectiveness and safety of ambulatory training in patients with acetabular dysplasia. To achieve this, we studied the hip joint moment in subjects walking with laterally and horizontally elevated arms and changing speeds as a form of training to strengthen hip joint abductor muscles. We studied eight women with pre- or early stage hip disease (center-edge angle of Wieberg 18.5 degrees to -3.0 degrees ) and six healthy women. In exercise task 1 the subjects walked at a rate of 90 steps/min, with abduction of 90 degrees in the shoulder joint ipsilateral or contralateral to the affected hip joint, and either no load or a 1 kg weight in either hand. In exercise task 2, walking speed was changed in three stages from 60 steps/min (s-gait), 90 steps/min (n-gait), and 120 steps/min (f-gait), with both hands swinging freely. Using results from a three-dimensional motion analysis system, the hip joint moments were calculated. In both the healthy and the acetabular dysplasia groups, the abduction moment of the hip joint decreased significantly with ipsilateral elevation and increased significantly with contralateral elevation. There was no significant change in hip flexion moment in either group. The hip extension moment decreased significantly with contralateral elevation, but no significant changes were seen in ipsilateral elevation. In the walking rate variation, the extension hip moment in fast gait was higher than in slow gait. It was concluded that ambulatory training with contralateral horizontal arm elevation may be an effective way of increasing hip joint abductor muscle strength. Ipsilateral arm elevation decreases gluteus medius muscle tension and is an effective way of ambulatory training for people with compensated trendelenburg gait. Variable speed walking is an effective exercise method that can strengthen extensor muscles. Therefore, these ambulatory training methods are useful for acetabular dysplasia patients.

  10. The effect of glycation on arterial microstructure and mechanical response.

    Science.gov (United States)

    Stephen, Elizabeth A; Venkatasubramaniam, Arundhathi; Good, Theresa A; Topoleski, L D T

    2014-08-01

    Like engineered materials, an artery's biomechanical behavior and function depend on its microstructure. Glycation is associated with both normal aging and diabetes and has been shown to increase arterial stiffness. In this study we examined the direct effect of glycation on the mechanical response of intact arteries and on the mechanical response and structure of elastin isolated from the arteries. Samples of intact arteries and isolated elastin were prepared from porcine aortas and glycated. The mechanical response of all samples was completed using a uniaxial material test system. Glycation levels were measured using ELISA. A confocal microscope was used to image differences in the structure of the glycated and untreated elastin fibers. We found that, under the conditions used in this study, glycation led to decreased stiffness of elastin isolated from arteries, which was associated with a thinning of elastin fibers as imaged by confocal microscopy. We observed no effect of glycation on collagen fibers under our treatment conditions. These results suggest that glycation leads to weakening of the elastin component of arteries that could contribute to vascular defects seen in diabetes and aging. Prevention of glycation reactions may be an important consideration for vascular health later in life.

  11. Pathway to Best Practice in Spirometry in the Ambulatory Setting.

    Science.gov (United States)

    Peracchio, Carol

    2016-01-01

    Spirometry performed in the ambulatory setting is an invaluable tool for diagnosis, monitoring, and evaluation of respiratory health in patients with chronic lung disease. If spirometry is not performed according to American Thoracic Society (ATS) guidelines, unnecessary repeated testing, increased expenditure of time and money, and increased patient and family anxiety may result. Two respiratory therapists at Mission Health System in Asheville, NC, identified an increase in patients arriving at the pulmonary function testing (PFT) laboratories with abnormal spirometry results obtained in the ambulatory setting. These abnormal results were due to incorrect testing procedure, not chronic lung disease. Three training methods were developed to increase knowledge of correct spirometry testing procedure in the ambulatory setting. The therapists also created a plan to educate offices that do not perform spirometry on the importance and availability of PFT services at our hospital for the population of patients with chronic lung disease. Notable improvements in posttraining test results were demonstrated. The education process was evaluated by a leading respiratory expert, with improvements suggested and implemented. Next steps are listed.

  12. Role of ambulatory blood pressure monitoring in resistant hypertension.

    Science.gov (United States)

    Grassi, Guido; Bombelli, Michele; Seravalle, Gino; Brambilla, Gianmaria; Dell'oro, Raffaella; Mancia, Giuseppe

    2013-06-01

    Ambulatory blood pressure monitoring has gained growing popularity in the diagnosis and treatment of essential hypertension for several reasons, such as the lack of the so-called white-coat effect, the greater reproducibility as compared with clinic blood pressure, the ability to provide information on blood pressure phenomena of prognostic value and the closer relationship with the risk of cardiovascular morbidity and mortality. All the above-mentioned main features of ambulatory blood pressure monitoring are also true for resistant hypertension. In addition, however, in resistant hypertension, blood pressure monitoring allows one to precisely define the diagnosis of this clinical condition, by excluding the presence of white-coat hypertension, which is responsible for a consistent number of "false" resistant hypertensive cases. The approach also allows one to define the patterns of blood pressure variability in this clinical condition, as well as its relationships with target organ damage. Finally, it allows one to assess the effects of therapeutic interventions, such as renal nerves ablation, aimed at improving blood pressure control in this hypertensive state. The present paper will critically review the main features of ambulatory blood pressure monitoring in resistant hypertension, with particular emphasis on the diagnosis and treatment of this high-risk hypertensive state.

  13. A vision for ambulatory care in the 21st century.

    Science.gov (United States)

    Zuckerman, A M

    1998-01-01

    The 1990's have been a remarkable decade for ambulatory care providers. Ambulatory care services have flourished in an era of rapidly increasing demands and seemingly limitless potential. Will the first decade of the next millennium continue this trend or is something new on the horizon? Ambulatory care's future prospects need to be evaluated within the context of the overall health care delivery environment of the future. At this time, three alternative "futures" seem plausible for the next decade. Managed care dominates. This scenario appears most likely at present with managed care poised to make significant inroads into Medicaid and Medicare populations. National health insurance is instituted. Some believe that this is a logical reaction to the excesses of the current competitive marketplace and is possible following the presidential election of 2004. Slow evolution of current system. This scenario may be viewed as the status quo alternative and is likely in the absence of a crisis or a better, generally agreed upon way in which to improve health care delivery.

  14. Ambulatory Melanoma Care Patterns in the United States

    Directory of Open Access Journals (Sweden)

    Andrew L. Ji

    2013-01-01

    Full Text Available Objective. To examine trends in melanoma visits in the ambulatory care setting. Methods. Data from the National Ambulatory Medical Care Survey (NAMCS from 1979 to 2010 were used to analyze melanoma visit characteristics including number of visits, age and gender of patients, and physician specialty. These data were compared to US Census population estimates during the same time period. Results. The overall rate of melanoma visits increased ( at an apparently higher rate than the increase in population over this time. The age of patients with melanoma visits increased at approximately double the rate (0.47 year per interval year, of the population increase in age (0.23 year per interval year. There was a nonsignificant decline in the proportion of female patients seen over the study interval. Lastly, ambulatory care has shifted towards dermatologists and other specialties managing melanoma patients and away from family/internal medicine physicians and general/plastic surgeons. Conclusions. The number and age of melanoma visits has increased over time with respect to the overall population, mirroring the increase in melanoma incidence over the past three decades. These trends highlight the need for further studies regarding melanoma management efficiency.

  15. Annotated Bibliography: Understanding Ambulatory Care Practices in the Context of Patient Safety and Quality Improvement.

    Science.gov (United States)

    Montano, Maria F; Mehdi, Harshal; Nash, David B

    2016-11-01

    The ambulatory care setting is an increasingly important component of the patient safety conversation. Inpatient safety is the primary focus of the vast majority of safety research and interventions, but the ambulatory setting is actually where most medical care is administered. Recent attention has shifted toward examining ambulatory care in order to implement better health care quality and safety practices. This annotated bibliography was created to analyze and augment the current literature on ambulatory care practices with regard to patient safety and quality improvement. By providing a thorough examination of current practices, potential improvement strategies in ambulatory care health care settings can be suggested. A better understanding of the myriad factors that influence delivery of patient care will catalyze future health care system development and implementation in the ambulatory setting.

  16. Altered diastolic function and aortic stiffness in Alzheimer’s disease

    Directory of Open Access Journals (Sweden)

    Çalık AN

    2014-07-01

    Full Text Available Ali Nazmi Çalik,3 Kazim Serhan Özcan,4 Gülbün Yüksel,2 Baris Güngör,1 Emre Arugarslan,1 Figen Varlibas,2 Ahmet Ekmekci,1 Damirbek Osmonov,1 Mustafa Adem Tatlisu,1 Mehmet Karaca,1 Osman Bolca,1 Izzet Erdinler1 1Department of Cardiology, Siyami Ersek Cardiovascular and Thoracic Surgery Center, Istanbul, Turkey; 2Department of Neurology, Haydarpasa Numune Training and Research Hospital, Istanbul, Turkey; 3Department of Cardiology, Yozgat State Hospital, Yozgat, Turkey; 4Department of Cardiology, Derince Training and Research Hospital, Kocaeli, Turkey Background: Alzheimer’s disease (AD is closely linked to cardiovascular risk factors.Methods: Echocardiographic studies were performed, including left ventricular diastolic functions, left and right atrial conduction times, and arterial stiffness parameters, namely stiffness index, pressure-strain elastic modulus, and distensibility, on 29 patients with AD and 24 age-matched individuals with normal cognitive function.Results: The peak mitral flow velocity of the early rapid filling wave (E was lower, and the peak velocity of the late filling wave caused by atrial contraction (A, deceleration time of peak E velocity, and isovolumetric relaxation time were higher in the AD group. The early myocardial peak (Ea velocity was significantly lower in AD patients, whereas the late diastolic (Aa velocity and E/Ea ratio were similar between the two groups. In Alzheimer patients, stiffness index and pressure-strain elastic modulus were higher, and distensibility was significantly lower in the AD group compared to the control. Interatrial electromechanical delay was significantly longer in the AD group.Conclusion: Our findings suggest that patients with AD are more likely to have diastolic dysfunction, higher atrial conduction times, and increased arterial stiffness compared to the controls of same sex and similar age. Keywords: diastolic dysfunction, atrial conduction timeA Letter to the Editor has been

  17. Stiffness of lipid monolayers with phase coexistence.

    Science.gov (United States)

    Caruso, Benjamín; Mangiarotti, Agustín; Wilke, Natalia

    2013-08-27

    The surface dilational modulus--or compressibility modulus--has been previously studied for monolayers composed of pure materials, where a jump in this modulus was related with the onset of percolation as a result of the establishment of a connected structure at the molecular level. In this work, we focused on monolayers composed of two components of low lateral miscibility. Our aim was to investigate the compressibility of mixed monolayers at pressures and compositions in the two-phase region of the phase diagram, in order to analyze the effect of the mechanical properties of each phase on the stiffness of the composite. In nine different systems with distinct molecular dipoles and charges, the stiffness of each phase and the texture at the plane of the monolayer were studied. In this way, we were able to analyze the general compressibility of two-phase lipid monolayers, regardless of the properties of their constituent parts. The results are discussed in the light of the following two hypotheses: first, the stiffness of the composite could be dominated by the stiffness of each phase as a weighted sum according to the percentage of each phase area, regardless of the distribution of the phases in the plane of the monolayer. Alternatively, the stiffness of the composite could be dominated by the mechanical properties of the continuous phase. Our results were better explained by this latter proposal, as in all the analyzed mixtures it was found that the mechanical properties of the percolating phase were the determining factors. The value of the compression modulus was closer to the value of the connected phase than to that of the dispersed phase, indicating that the bidimensional composites displayed mechanical properties that were related to the properties of each phases in a rather complex manner.

  18. ON THE STIFFNESS OF DEMINERALIZED DENTIN MATRICES

    Science.gov (United States)

    Ryou, Heonjune; Turco, Gianluca; Breschi, Lorenzo; Tay, Franklin R.; Pashley, David H.; Arola, Dwayne

    2015-01-01

    Resin bonding to dentin requires the use of self-etching primers or acid etching to decalcify the surface and expose a layer of collagen fibrils of the dentin matrix. Acid-etching reduces the stiffness of demineralized dentin from approximately 19 GPa to 1 MPa, requiring that it floats in water to prevent it from collapsing during bonding procedures. Several publications show that crosslinking agents like gluteraladehyde, carbodiimide or grape seed extract can stiffen collagen and improve resin-dentin bond strength. Objective The objective was to assess a new approach for evaluating the changes in stiffness of decalcified dentin by polar solvents and a collagen cross-linker. Methods Fully demineralized dentin beams and sections of etched coronal dentin were subjected to indentation loading using a cylindrical flat indenter in water, and after treatment with ethanol or ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC). The stiffness was measured as a function of strain and as a function of loading rate from 1 to 50 µm/sec. Results At a strain of 0.25% the elastic modulus of the fully demineralized dentin was approximately 0.20 MPa. It increased to over 0.90 MPa at strains of 1%. Exposure to ethanol caused an increase in elastic modulus of up to four times. Increasing the loading rate from 1 to 50 µm/sec caused an increase in the apparent modulus of up to three times in both water and ethanol. EDC treatment caused increases in the stiffness in fully demineralized samples and in acid-etched demineralized dentin surfaces in situ. Significance Changes in the mechanical behavior of demineralized collagen matrices can be measured effectively under hydration via indentation with cylindrical flat indenters. This approach can be used for quantifying the effects of bonding treatments on the properties of decalcified dentin after acid etching, as well as to follow the loss of stiffness over time due to enzymatic degradation. PMID:26747822

  19. Irbesartan improves arterial compliance more than lisinopril

    Science.gov (United States)

    Ali, Khalid; Rajkumar, Chakravarthi; Fantin, Francesco; Schiff, Rebekah; Bulpitt, Christopher J

    2009-01-01

    Background Antihypertensive agents can reduce arterial stiffness. We hypothesized that an angiotensin receptor blocker (ARB) irbesartan and an angiotensin converting enzyme inhibitor (ACEI) lisinopril improved arterial compliance. Methods A randomized, double-blind, double-dummy, controlled crossover trial. Fifteen hypertensive patients, mean age 65.5 ± 8.9 years (mean ± SD) were given irbesartan (150 to 300 mg/day) or lisinopril (10 to 20 mg/day) for 12 weeks and then crossed over for 12 weeks. Pulse wave velocity (PWV) in the carotid-femoral (CF), carotid-radial (CR), and femoral dorsalis-pedis (FD) were measured using a Complior® PWV system. Results After 12 weeks, systolic blood pressure (SBP) decreased from 162.4 ± 12.9 to 134.5 ± 14.8 with irbesartan and to 145.2 ± 25 mmHg with lisinopril. Irbesartan and lisinopril reduced PWV (CF) in the elastic arterial system from 15.1 ± 5 to 13.3 ± 2.6 (p < 0.005) and to 14 ± 4.7 (p < 0.05) m/s respectively (p = 0.345). Irbesartan reduced PWV (CR) and PWV (FD), whereas lisinopril did not. The difference between treatments was significant after SBP adjustment (p = 0.037 for PWV (CR) and p < 0.001 for PWV (FD)). Conclusions Irbesartan improved arterial compliance in elastic and muscular arteries, whereas lisinopril improved it only in elastic arteries. PMID:19649309

  20. Effect of coronary occlusion during percutaneous transluminal angioplasty in humans on left ventricular chamber stiffness and regional diastolic pressure-radius relations

    NARCIS (Netherlands)

    W. Wijns (William); P.W.J.C. Serruys (Patrick); C.J. Slager (Cornelis); J. Grimm; H.P. Krayenbuehl; P.G. Hugenholtz (Paul); O.M. Hess (Otto)

    1986-01-01

    textabstractThe effect of repeated (3 to 10 second) and transient (15 to 75 second) abrupt coronary occlusion on the global and regional chamber stiffness was studied in nine patients undergoing angioplasty of a single proximal left anterior descending coronary artery stenosis. The left ventricular

  1. Laterality and imbalance of muscle stiffness relate to personality.

    Science.gov (United States)

    Nakaya, Naoki; Kumano, Hiroaki; Minoda, Keiji; Kanazawa, Motoyori; Fukudo, Shin

    2004-01-01

    The authors' purpose in this study was to test the hypothesis that laterality and imbalance of muscle stiffness relate to personality. The authors selected 23 healthy volunteers and divided them into two groups based on the predominance of muscle stiffness on the left or right side. Imbalance of muscle stiffness was calculated as the absolute value of the difference of muscle stiffness between the right and left sides. The authors evaluated personality with the Japanese version of the Eysenck Personality Questionnaire. Subjects with left predominant muscle stiffness of the rectal abdominis had significantly higher neuroticism score than those with right predominant muscle stiffness. Subjects with more imbalance of muscle stiffness in the latissimus dorsi and in the trapezius had significantly higher neuroticism and psychoticism scores than those with less imbalance. The findings suggest that laterality and imbalance of muscle stiffness relate to personality.

  2. A review on in situ stiffness adjustment methods in MEMS

    Science.gov (United States)

    de Laat, M. L. C.; Pérez Garza, H. H.; Herder, J. L.; Ghatkesar, M. K.

    2016-06-01

    In situ stiffness adjustment in microelectromechanical systems is used in a variety of applications such as radio-frequency mechanical filters, energy harvesters, atomic force microscopy, vibration detection sensors. In this review we provide designers with an overview of existing stiffness adjustment methods, their working principle, and possible adjustment range. The concepts are categorized according to their physical working principle. It is concluded that the electrostatic adjustment principle is the most applied method, and narrow to wide ranges in stiffness can be achieved. But in order to obtain a wide range in stiffness change, large, complex devices were designed. Mechanical stiffness adjustment is found to be a space-effective way of obtaining wide changes in stiffness, but these methods are often discrete and require large tuning voltages. Stiffness adjustment through stressing effects or change in Young’s modulus was used only for narrow ranges. The change in second moment of inertia was used for stiffness adjustment in the intermediate range.

  3. A novel energy-efficient rotational variable stiffness actuator

    NARCIS (Netherlands)

    Rao, Shodhan; Carloni, Raffaella; Stramigioli, Stefano

    2011-01-01

    This paper presents the working principle, the design and realization of a novel rotational variable stiffness actuator, whose stiffness can be varied independently of its output angular position. This actuator is energy-efficient, meaning that the stiffness of the actuator can be varied by keeping

  4. How Crouch Gait Can Dynamically Induce Stiff-Knee Gait

    NARCIS (Netherlands)

    Van der Krogt, M.M.; Bregman, D.J.J.; Wisse, M.; Doorenbosch, C.A.M.; Harlaar, J.; Collins, S.H.

    Children with cerebral palsy frequently experience foot dragging and tripping during walking due to a lack of adequate knee flexion in swing (stiff-knee gait). Stiff-knee gait is often accompanied by an overly flexed knee during stance (crouch gait). Studies on stiff-knee gait have mostly focused on

  5. Non-dipping status in arterial hypertension: an overview.

    Science.gov (United States)

    Sarigianni, Maria; Dimitrakopoulos, Konstantinos; Tsapas, Apostolos

    2014-05-01

    Non-dipping is a common pattern of arterial hypertension and it is associated with increased cardiovascular risk. Use of ambulatory blood pressure monitoring, as suggested in recent guidelines, could further increase its prevalence among subjects with hypertension. In this review we discuss assessment, relevance and associated factors. Non-dipping could be addressed through chronotherapy, the use of specific classes of anti-hypertensives, such as renin-angiotensin blockers, or modification of associated factors. However, more data are needed in order to comprehensively estimate factors associated with non-dipping and how they could be modified.

  6. Secondary Headaches Attributed to Arterial Hypertension

    Directory of Open Access Journals (Sweden)

    Farhad Assarzadegan

    2013-07-01

    Full Text Available Mild (140 to 159/90 to 99 mmHg or moderate (160 to 179/100 to 109 mmHg chronic arterial hypertension does not appear to cause headache. Whether moderate hypertension predisposes patients to headache at all remains controversial, but there is little evidence that it does. Ambulatory blood pressure monitoring in patients with mild and moderate hypertension has shown no convincing relationship between blood pressure fluctuations over a 24-hour period and presence or absence of headache. However, headaches are associated to various disorders that lead to abrupt, severe, and paroxysmal elevations in blood pressure. In this paper, the secondary headaches attributed to acute crises of hypertension and the criteria for diagnosing each of them have been reviewed. These are headaches attributed to pheochromocytoma, hypertensive crisis without encephalopathy, hypertensive encephalopathy, pre-eclampsia, eclampsia, and acute pressure response to exogenous agents.

  7. [Stiff person syndrome--case report].

    Science.gov (United States)

    Tomczykiewicz, Kazimierz; Pastuszak, Zanna; Staszewski, Jacek; Stepień, Adam

    2014-01-01

    Stiff person syndrome (SPS) is the rare disease and cause great inefficient. It is characterized by progressive stiffness muscles of trunk and the limbs on which the cramps of muscles overlap. In the electrophysiological investigation of the patients the involuntary discharge of motor unit potentials find and also simultaneous contraction agonistic and antagonistic muscles. SPS is presented with insulin-dependent diabetes mellitus often or is the symptom of the paraneoplastic syndrome. It is commonly associated with high anti-glutamic acid decarboxylaze (GAD) antibody titters in the serum of the blood of patients. Establishing the diagnosis can cause difficulties. We observed the patient in the last period about the atypical course the disease. The diagnosis was confirmed occurrences of the high titters of antibodies anti-GAD, the discharge of motor unit potential in paraspinal muscles in the rest and good response the treatment with diazepamem.

  8. Electron profile stiffness and critical gradient studies

    Science.gov (United States)

    DeBoo, J. C.; Petty, C. C.; White, A. E.; Burrell, K. H.; Doyle, E. J.; Hillesheim, J. C.; Holland, C.; McKee, G. R.; Rhodes, T. L.; Schmitz, L.; Smith, S. P.; Wang, G.; Zeng, L.

    2012-08-01

    Electron profile stiffness was studied in DIII-D L-mode discharges by systematically varying the heat flux in a narrow region with electron cyclotron heating and measuring the local change produced in ∇Te. Electron stiffness was found to slowly increase with toroidal rotation velocity. A critical inverse temperature gradient scale length 1/LC ˜ 3 m-1 was identified at ρ =0.6 and found to be independent of rotation. Both the heat pulse diffusivity and the power balance diffusivity, the latter determined by integrating the measured dependence of the heat pulse diffusivity on -∇Te, were fit reasonably well by a model containing a critical inverse temperature gradient scale length and varying linearly with 1/LT above the threshold.

  9. Stiff modes in spinvalve simulations with OOMMF

    Energy Technology Data Exchange (ETDEWEB)

    Mitropoulos, Spyridon [Department of Computer and Informatics Engineering, TEI of Eastern Macedonia and Thrace, Kavala (Greece); Tsiantos, Vassilis, E-mail: tsianto@teikav.edu.gr [Department of Electrical Engineering, TEI of Eastern Macedonia and Thrace, Kavala, 65404 Greece (Greece); Ovaliadis, Kyriakos [Department of Electrical Engineering, TEI of Eastern Macedonia and Thrace, Kavala, 65404 Greece (Greece); Kechrakos, Dimitris [Department of Education, ASPETE, Heraklion, Athens (Greece); Donahue, Michael [Applied and Computational Mathematics Division, NIST, Gaithersburg, MD (United States)

    2016-04-01

    Micromagnetic simulations are an important tool for the investigation of magnetic materials. Micromagnetic software uses various techniques to solve differential equations, partial or ordinary, involved in the dynamic simulations. Euler, Runge-Kutta, Adams, and BDF (Backward Differentiation Formulae) are some of the methods used for this purpose. In this paper, spinvalve simulations are investigated. Evidence is presented showing that these systems have stiff modes, and that implicit methods such as BDF are more effective than explicit methods in such cases.

  10. The stiffness change and the increase in the ultimate capacity for a stiff pile resulting from a cyclic loading

    DEFF Research Database (Denmark)

    Lada, Aleksandra; Ibsen, Lars Bo; Nicolai, Giulio

    In the paper the experimental results of small-scale tests on a stiff monopile are presented to outline the change in stiffness during the cyclic loading and the change in the ultimate pile capacity. The results confirm the increase of stiffness and the increase in bearing capacity resulting from...... cyclic loading. Performed analysis provides a better understanding of the problem and reveals some correlations that can be useful in the future design of stiff monopiles....

  11. Efficient Method for Calculating the Composite Stiffness of Parabolic Leaf Springs with Variable Stiffness for Vehicle Rear Suspension

    OpenAIRE

    Wen-ku Shi; Cheng Liu; Zhi-yong Chen; Wei He; Qing-hua Zu

    2016-01-01

    The composite stiffness of parabolic leaf springs with variable stiffness is difficult to calculate using traditional integral equations. Numerical integration or FEA may be used but will require computer-aided software and long calculation times. An efficient method for calculating the composite stiffness of parabolic leaf springs with variable stiffness is developed and evaluated to reduce the complexity of calculation and shorten the calculation time. A simplified model for double-leaf spr...

  12. Arterial structure and function in inflammatory bowel disease.

    Science.gov (United States)

    Zanoli, Luca; Rastelli, Stefania; Inserra, Gaetano; Castellino, Pietro

    2015-10-28

    Inflammatory bowel disease (IBD) is the result of a combination of environmental, genetic and immunologic factors that trigger an uncontrolled immune response within the intestine, which results in inflammation among genetically predisposed individuals. Several studies have reported that the prevalence of classic cardiovascular risk factors is lower among subjects with IBD than in the general population, including obesity, dyslipidaemia, diabetes and hypertension. Therefore, given the risk profile of IBD subjects, the expected cardiovascular morbidity and mortality should be lower in these patients than in the general population. However, this is not the case because the standardized mortality ratio is not reduced and the risk of coronary heart disease is increased in patients with IBD. It is reasonable to hypothesize that other factors not considered in the classical stratification of cardiovascular risk may be involved in these subjects. Therefore, IBD may be a useful model with which to evaluate the effects of chronic low-grade inflammation in the development of cardiovascular diseases. Arterial stiffness is both a marker of subclinical target organ damage and a cardiovascular risk factor. In diseases characterized by chronic systemic inflammation, there is evidence that the inflammation affects arterial properties and induces both endothelial dysfunction and arterial stiffening. It has been reported that decreasing inflammation via anti tumor necrosis factor alpha therapy decreases arterial stiffness and restores endothelial function in patients with chronic inflammatory disorders. Consistent with these results, several recent studies have been conducted to determine whether arterial properties are altered among patients with IBD. In this review, we discuss the evidence pertaining to arterial structure and function and present the available data regarding arterial stiffness and endothelial function in patients with IBD.

  13. Induction of sexual arousal in women under conditions of institutional and ambulatory laboratory circumstances: a comparative study

    NARCIS (Netherlands)

    J. Bloemers; J. Gerritsen; R. Bults; H. Koppeschaar; W. Everaerd; B. Olivier; A. Tuiten

    2010-01-01

    Introduction. Measuring under naturally occurring circumstances increases ecological validity. We developed an ambulatory psychophysiological laboratory that allows experiments to be performed at home. Aims.  To compare institutional laboratory task measures with ambulatory laboratory task measures.

  14. A General Formulation for the Stiffness Matrix of Parallel Mechanisms

    CERN Document Server

    Quennouelle, Cyril

    2012-01-01

    Starting from the definition of a stiffness matrix, the authors present a new formulation of the Cartesian stiffness matrix of parallel mechanisms. The proposed formulation is more general than any other stiffness matrix found in the literature since it can take into account the stiffness of the passive joints, it can consider additional compliances in the joints or in the links and it remains valid for large displacements. Then, the validity, the conservative property, the positive definiteness and the relation with other formulations of stiffness matrices are discussed theoretically. Finally, a numerical example is given in order to illustrate the correctness of this matrix.

  15. Peripheral arterial line (image)

    Science.gov (United States)

    A peripheral arterial line is a small, short plastic catheter placed through the skin into an artery of the arm or leg. The purpose of a peripheral arterial line is to allow continuous monitoring of ...

  16. Educating Asthmatic Children in European Ambulatory Pediatrics: Facts and Insights.

    Science.gov (United States)

    Robberecht, Marie Noëlle; Beghin, Laurent; Deschildre, Antoine; Hue, Valérie; Reali, Laura; Plevnik-Vodušek, Vesna; Moretto, Marilena; Agustsson, Sigurlaug; Tockert, Emile; Jäger-Roman, Elke; Deplanque, Dominique; Najaf-Zadeh, Abolfazl; Martinot, Alain

    2015-01-01

    The aim of this study was to assess the role of European ambulatory pediatricians in caring for asthmatic children, especially in terms of their therapeutic education. We developed a survey that was observational, declarative, retrospective and anonymous in nature. 436 ambulatory pediatricians in Belgium, France, Germany, Italy, Luxembourg and Slovenia were asked to participate in the survey providing information on three children over 6 years old suffering from persistent asthma, who had been followed for at least 6 months. We considered the pediatricians' profile, and their role in the therapeutic education of children. 277 pediatricians (64%) responded: 81% were primary care pediatricians; 46% participated in networks; 4% had specific training in Therapeutic Patient Education; 69% followed more than 5 asthmatic children per month, and over long periods (7 ± 4 years). The profiles of 684 children were assessed. Answers diverged concerning the provision of a Personalized Action Plan (60-88%), training the child to measure and interpret his Peak Expiratory Flow (31-99%), and the prescription of pulmonary function tests during the follow-up programme of consultations (62-97%). Answers converged on pediatricians' perception of their role in teaching children about their condition and its treatment (99%), about inhalation techniques (96%), and in improving the children's ability to take preventive measures when faced with risk situations (97%). This study highlights the role of European pediatricians in caring for asthmatic children, and their lack of training in Therapeutic Patient Education. Programmes and tools are required in order to train ambulatory pediatricians in Therapeutic Patient Education, and such resources should be integrated into primary health care, and harmonized at the European level.

  17. Strategies to reduce medication errors in pediatric ambulatory settings

    Directory of Open Access Journals (Sweden)

    S Mehndiratta

    2012-01-01

    Full Text Available Worldwide, a large number of children are prescribed drugs on an outpatient basis. Medication errors are fairly common in these settings. Though this matter has been well recognized as a cause of concern, limited data is available from ambulatory settings. Medication errors can be defined as errors that may occur at any step, starting from ordering a medication, to dispensing, administration of the drug and the subsequent monitoring. The outcomes of such errors are variable and may range between those that are clinically insignificant to a life-threatening event. The reasons for these medication errors are multi-factorial. Children are unable to administer medications to themselves and also require a strict weight-based dosing regimen. The risk factors associated with medication errors include complex regimens with multiple medications. Overdosing and under-dosing (10-fold calculation errors, an increased or a decreased frequency of dosing or an inappropriate duration of administration of the medication, are frequently detected errors. The lack of availability of proper formulations adds to the confusion. The low level of literacy among the caregivers can aggravate this problem. There is a lack of proper reporting and monitoring mechanisms in most ambulatory settings, hence these errors remain unrecognized and often go unreported. This article summarizes the current available literature on medication errors in ambulatory settings and the possible strategies that can be adopted to reduce the burden of these errors in order to improve child care and patient safety. Voluntary, anonymous reporting can be introduced in the healthcare institutions to determine the incidence of these errors.

  18. Ambulatory surgery with chloroprocaine spinal anesthesia: a review

    Directory of Open Access Journals (Sweden)

    Ghisi D

    2015-11-01

    Full Text Available Daniela Ghisi, Stefano Bonarelli Department of Anaesthesia and Postoperative Intensive Care, Istituto Ortopedico Rizzoli, Bologna, Italy Abstract: Spinal anesthesia is a reliable and safe technique for procedures of the lower extremities. Nevertheless, some of its characteristics may limit its use for ambulatory surgery, including delayed ambulation, risk of urinary retention, and pain after block regression. The current availability of short-acting local anesthetics has renewed interest for this technique also in the context of short- and ultra-short procedures. Chloroprocaine (CP is an amino-ester local anesthetic with a very short half-life. It was introduced and has been successfully used for spinal anesthesia since 1952. Sodium bisulfite was then added as a preservative after 1956. The drug was then abandoned in the 1980s for several reports of neurological deficits in patients receiving accidentally high doses of intrathecal CP during epidural labor analgesia. Animal studies have proven the safety of the preservative-free formulation, which has been extensively evaluated in volunteer studies as well as in clinical practice with a favorable profile in terms of both safety and efficacy. In comparison with bupivacaine, 2-chloroprocaine (2-CP showed faster offset times to end of anesthesia, unassisted ambulation, and discharge from hospital. These findings suggests that 2-CP may be a suitable alternative to low doses of long-acting local anesthetics in ambulatory surgery. Its safety profile also suggests that 2-CP could be a valid substitute for intrathecal short- and intermediate-acting local anesthetics, such as lidocaine and mepivacaine – often causes of transient neurological symptoms. In this context, literature suggests a dose ranging between 30 and 60 mg of 2-CP for procedures lasting 60 minutes or less, while 10 mg is considered the no-effect dose. The present review describes recent evidence about 2-CP as an anesthetic agent for

  19. Regional variations in ambulatory care and incidence of cardiovascular events

    Science.gov (United States)

    Tu, Jack V.; Chu, Anna; Maclagan, Laura; Austin, Peter C.; Johnston, Sharon; Ko, Dennis T.; Cheung, Ingrid; Atzema, Clare L.; Booth, Gillian L.; Bhatia, R. Sacha; Lee, Douglas S.; Jackevicius, Cynthia A.; Kapral, Moira K.; Tu, Karen; Wijeysundera, Harindra C.; Alter, David A.; Udell, Jacob A.; Manuel, Douglas G.; Mondal, Prosanta; Hogg, William

    2017-01-01

    BACKGROUND: Variations in the prevalence of traditional cardiac risk factors only partially account for geographic variations in the incidence of cardiovascular disease. We examined the extent to which preventive ambulatory health care services contribute to geographic variations in cardiovascular event rates. METHODS: We conducted a cohort study involving 5.5 million patients aged 40 to 79 years in Ontario, Canada, with no hospital stays for cardiovascular disease as of January 2008, through linkage of multiple population-based health databases. The primary outcome was the occurrence of a major cardiovascular event (myocardial infarction, stroke or cardiovascular-related death) over the following 5 years. We compared patient demographics, cardiac risk factors and ambulatory health care services across the province’s 14 health service regions, known as Local Health Integration Networks (LHINs), and evaluated the contribution of these variables to regional variations in cardiovascular event rates. RESULTS: Cardiovascular event rates across LHINs varied from 3.2 to 5.7 events per 1000 person-years. Compared with residents of high-rate LHINs, those of low-rate health regions received physician services more often (e.g., 4.2 v. 3.5 mean annual family physician visits, p value for LHIN-level trend = 0.01) and were screened for risk factors more often. Low-rate LHINs were also more likely to achieve treatment targets for hypercholes-terolemia (51.8% v. 49.6% of patients, p = 0.03) and controlled hypertension (67.4% v. 53.3%, p = 0.04). Differences in patient and health system factors accounted for 74.5% of the variation in events between LHINs, of which 15.5% was attributable to health system factors alone. INTERPRETATION: Preventive ambulatory health care services were provided more frequently in health regions with lower cardiovascular event rates. Health system interventions to improve equitable access to preventive care might improve cardiovascular outcomes. PMID

  20. Cosmology with a stiff matter era

    Science.gov (United States)

    Chavanis, Pierre-Henri

    2015-11-01

    We consider the possibility that the Universe is made of a dark fluid described by a quadratic equation of state P =K ρ2 , where ρ is the rest-mass density and K is a constant. The energy density ɛ =ρ c2+K ρ2 is the sum of two terms: a rest-mass term ρ c2 that mimics "dark matter" (P =0 ) and an internal energy term u =K ρ2=P that mimics a "stiff fluid" (P =ɛ ) in which the speed of sound is equal to the speed of light. In the early universe, the internal energy dominates and the dark fluid behaves as a stiff fluid (P ˜ɛ , ɛ ∝a-6). In the late universe, the rest-mass energy dominates and the dark fluid behaves as pressureless dark matter (P ≃0 , ɛ ∝a-3). We provide a simple analytical solution of the Friedmann equations for a universe undergoing a stiff matter era, a dark matter era, and a dark energy era due to the cosmological constant. This analytical solution generalizes the Einstein-de Sitter solution describing the dark matter era, and the Λ CDM model describing the dark matter era and the dark energy era. Historically, the possibility of a primordial stiff matter era first appeared in the cosmological model of Zel'dovich where the primordial universe is assumed to be made of a cold gas of baryons. A primordial stiff matter era also occurs in recent cosmological models where dark matter is made of relativistic self-gravitating Bose-Einstein condensates (BECs). When the internal energy of the dark fluid mimicking stiff matter is positive, the primordial universe is singular like in the standard big bang theory. It expands from an initial state with a vanishing scale factor and an infinite density. We consider the possibility that the internal energy of the dark fluid is negative (while, of course, its total energy density is positive), so that it mimics anti-stiff matter. This happens, for example, when the BECs have an attractive self-interaction with a negative scattering length. In that case, the primordial universe is nonsingular and

  1. Regional brain stiffness changes across the Alzheimer's disease spectrum.

    Science.gov (United States)

    Murphy, Matthew C; Jones, David T; Jack, Clifford R; Glaser, Kevin J; Senjem, Matthew L; Manduca, Armando; Felmlee, Joel P; Carter, Rickey E; Ehman, Richard L; Huston, John

    2016-01-01

    Magnetic resonance elastography (MRE) is an MRI-based technique to noninvasively measure tissue stiffness. Currently well established for clinical use in the liver, MRE is increasingly being investigated to measure brain stiffness as a novel biomarker of a variety of neurological diseases. The purpose of this work was to apply a recently developed MRE pipeline to measure regional brain stiffness changes in human subjects across the Alzheimer's disease (AD) spectrum, and to gain insights into the biological processes underlying those stiffness changes by correlating stiffness with existing biomarkers of AD. The results indicate that stiffness changes occur mostly in the frontal, parietal and temporal lobes, in accordance with the known topography of AD pathology. Furthermore, stiffness in those areas correlates with existing imaging biomarkers of AD including hippocampal volumes and amyloid PET. Additional analysis revealed preliminary but significant evidence that the relationship between brain stiffness and AD severity is nonlinear and non-monotonic. Given that similar relationships have been observed in functional MRI experiments, we used task-free fMRI data to test the hypothesis that brain stiffness was sensitive to structural changes associated with altered functional connectivity. The analysis revealed that brain stiffness is significantly and positively correlated with default mode network connectivity. Therefore, brain stiffness as measured by MRE has potential to provide new and essential insights into the temporal dynamics of AD, as well as the relationship between functional and structural plasticity as it relates to AD pathophysiology.

  2. Flexible Capacitive Electrodes for Minimizing Motion Artifacts in Ambulatory Electrocardiograms

    Directory of Open Access Journals (Sweden)

    Jeong Su Lee

    2014-08-01

    Full Text Available This study proposes the use of flexible capacitive electrodes for reducing motion artifacts in a wearable electrocardiogram (ECG device. The capacitive electrodes have conductive foam on their surface, a shield, an optimal input bias resistor, and guarding feedback. The electrodes are integrated in a chest belt, and the acquired signals are transmitted wirelessly for ambulatory heart rate monitoring. We experimentally validated the electrode performance with subjects standing and walking on a treadmill at speeds of up to 7 km/h. The results confirmed the highly accurate heart rate detection capacity of the developed system and its feasibility for daily-life ECG monitoring.

  3. Twenty-five years of ambulatory laparoscopic cholecystectomy.

    Science.gov (United States)

    Bueno Lledó, José; Granero Castro, Pablo; Gomez I Gavara, Inmaculada; Ibañez Cirión, Jose L; López Andújar, Rafael; García Granero, Eduardo

    2016-10-01

    It is accepted by the surgical community that laparoscopic cholecystectomy (LC) is the technique of choice in the treatment of symptomatic cholelithiasis. However, more controversial is the standardization of system implementation in Ambulatory Surgery because of its different different connotations. This article aims to update the factors that influence the performance of LC in day surgery, analyzing the 25 years since its implementation, focusing on the quality and acceptance by the patient. Individualization is essential: patient selection criteria and the implementation by experienced teams in LC, are factors that ensure high guarantee of success.

  4. Scheduling of procedures and staff in an ambulatory surgery center.

    Science.gov (United States)

    Pash, Joel; Kadry, Bassam; Bugrara, Suhabe; Macario, Alex

    2014-06-01

    For ambulatory surgical centers (ASC) to succeed financially, it is critical for ASC managers to schedule surgical procedures in a manner that optimizes operating room (OR) efficiency. OR efficiency is maximized by using historical data to accurately predict future OR workload, thereby enabling OR time to be properly allocated to surgeons. Other strategies to maintain a well-functioning ASC include recruiting and retaining the right staff and ensuring patients and surgeons are satisfied with their experience. This article reviews different types of procedure scheduling systems. Characteristics of well-functioning ASCs are also discussed.

  5. On prestress stiffness analysis of bolt-plate contact assemblies

    DEFF Research Database (Denmark)

    Pedersen, Niels Leergaard; Pedersen, Pauli

    2008-01-01

    Bolt connections are among the most important connections used in structures. The stiffnesses of the bolt and of the connected members are the primary qualities that control the lifetime of the connection. The stiffness of the bolt can be estimated rather easily, in contrast to the member stiffness......, but with finite element (FE) and contact analysis, it is possible to find the stiffness of the member. In the case of many connections and for practical applications, it is not suitable to make a full FE analysis. The purpose of the present paper is to find simplified expressions for the stiffness of the member......, including the case when the width of the member is limited. The calculation of the stiffness is based on the FE, including the solution to the contact problem, and we express the stiffness as a function of the elastic energy in the structure, whereby the definition of the displacements related...

  6. Nanocharacterization of the negative stiffness of ferroelectric materials

    Science.gov (United States)

    Alipour Skandani, A.; Ctvrtlik, R.; Al-Haik, M.

    2014-08-01

    Phase changing materials such as ferroelectric materials could exhibit negative stiffness under certain thermomechanical environments. This negative stiffness is embodied by a deflection along the opposite direction of the applied load. So far negative stiffness materials were investigated with the specific morphology of embedded inclusions in stiff matrices then the resulting composite is studied to measure the behavior of each constituent indirectly. In this study, a modified nonisothermal nanoindentation method is developed to measure the negative stiffness of triglycine sulfate single crystal directly. This in-situ method is intended to first demonstrate the feasibility of detecting the negative stiffness via nanoindentation and nanocreep of a ferroelectric material at its Curie point and then to quantify the negative stiffness without the need for embedding the crystal within a stiffer matrix.

  7. 76 FR 65885 - Medicare Program; Changes to the Ambulatory Surgical Centers Patient Rights Conditions for Coverage

    Science.gov (United States)

    2011-10-24

    ... 42 CFR Chapter IV Medicare and Medicaid Programs; Changes to the Ambulatory Surgical Centers Patient... Service 42 CFR Part 416 RlN 0938-AP93 Medicare Program; Changes to the Ambulatory Surgical Centers Patient..., or the patient's surrogate prior to the start of the surgical procedure. In addition, we made...

  8. Estimating qualitative parameters for assessment of body balance and arm function in a simulated ambulatory setting

    NARCIS (Netherlands)

    Meulen, van Fokke B.; Reenalda, Jasper; Veltink, Peter H.

    2013-01-01

    Continuous daily-life monitoring of balance control and arm function of stroke survivors in an ambulatory setting, is essential for optimal guidance of rehabilitation. In a simulated ambulatory setting, balance and arm function of seven stroke subjects is evaluated using on-body measurement systems

  9. 42 CFR 419.31 - Ambulatory payment classification (APC) system and payment weights.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Ambulatory payment classification (APC) system and... Outpatient Services § 419.31 Ambulatory payment classification (APC) system and payment weights. (a) APC... the Federal Food, Drug and Cosmetic Act. (3) The payment rate determined for an APC group...

  10. Increased systolic ambulatory blood pressure and microalbuminuria in treated and non-treated hypertensive smokers

    DEFF Research Database (Denmark)

    Sørensen, Kaspar; Kristensen, Kjeld S; Bang, Lia E;

    2004-01-01

    The primary aim of the present study was to evaluate the impact of smoking status on both clinic and ambulatory blood pressure (BP) and heart rate (HR) by using 24-h ambulatory BP monitoring in treated and non-treated hypertensive smokers and non-smokers. A secondary aim was to evaluate the inter...... the interrelations between BP, smoking status and microalbuminuria....

  11. Adopting Ambulatory Breast Cancer Surgery as the Standard of Care in an Asian Population

    Directory of Open Access Journals (Sweden)

    Yvonne Ying Ru Ng

    2014-01-01

    Full Text Available Introduction. Ambulatory surgery is not commonly practiced in Asia. A 23-hour ambulatory (AS23 service was implemented at our institute in March 2004 to allow more surgeries to be performed as ambulatory procedures. In this study, we reviewed the impact of the AS23 service on breast cancer surgeries and reviewed surgical outcomes, including postoperative complications, length of stay, and 30-day readmission. Methods. Retrospective review was performed of 1742 patients who underwent definitive breast cancer surgery from 1 March 2004 to 31 December 2010. Results. By 2010, more than 70% of surgeries were being performed as ambulatory procedures. Younger women (P<0.01, those undergoing wide local excision (P<0.01 and those with ductal carcinoma-in situ or early stage breast cancer (P<0.01, were more likely to undergo ambulatory surgery. Six percent of patients initially scheduled for ambulatory surgery were eventually managed as inpatients; a third of these were because of perioperative complications. Wound complications, 30-day readmission and reoperation rates were not more frequent with ambulatory surgery. Conclusion. Ambulatory breast cancer surgery is now the standard of care at our institute. An integrated workflow facilitating proper patient selection and structured postoperativee outpatient care have ensured minimal complications and high patient acceptance.

  12. Automatic classification of long-term ambulatory ECG records according to type of ischemic heart disease

    Directory of Open Access Journals (Sweden)

    Smrdel Aleš

    2011-12-01

    Full Text Available Abstract Background Elevated transient ischemic ST segment episodes in the ambulatory electrocardiographic (AECG records appear generally in patients with transmural ischemia (e. g. Prinzmetal's angina while depressed ischemic episodes appear in patients with subendocardial ischemia (e. g. unstable or stable angina. Huge amount of AECG data necessitates automatic methods for analysis. We present an algorithm which determines type of transient ischemic episodes in the leads of records (elevations/depressions and classifies AECG records according to type of ischemic heart disease (Prinzmetal's angina; coronary artery diseases excluding patients with Prinzmetal's angina; other heart diseases. Methods The algorithm was developed using 24-hour AECG records of the Long Term ST Database (LTST DB. The algorithm robustly generates ST segment level function in each AECG lead of the records, and tracks time varying non-ischemic ST segment changes such as slow drifts and axis shifts to construct the ST segment reference function. The ST segment reference function is then subtracted from the ST segment level function to obtain the ST segment deviation function. Using the third statistical moment of the histogram of the ST segment deviation function, the algorithm determines deflections of leads according to type of ischemic episodes present (elevations, depressions, and then classifies records according to type of ischemic heart disease. Results Using 74 records of the LTST DB (containing elevated or depressed ischemic episodes, mixed ischemic episodes, or no episodes, the algorithm correctly determined deflections of the majority of the leads of the records and correctly classified majority of the records with Prinzmetal's angina into the Prinzmetal's angina category (7 out of 8; majority of the records with other coronary artery diseases into the coronary artery diseases excluding patients with Prinzmetal's angina category (47 out of 55; and correctly

  13. Ambulatory Surgical Facilities, Licensed Ambulatory Sugery Centers, Published in 2007, 1:24000 (1in=2000ft) scale, State of California - Office of the State Chief Information Officer.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Ambulatory Surgical Facilities dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Published Reports/Deeds information as of...

  14. Ambulatory Surgical Facilities, Identify the locations of Ambulatory Surgical Centers, Published in 2012, 1:2400 (1in=200ft) scale, Miami-Dade County, Information Technology Department.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Ambulatory Surgical Facilities dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Other information as of 2012. It is described as...

  15. Assessment of placental stiffness using acoustic radiation force impulse elastography in pregnant women with fetal anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Alan, Bircan; Goya, Cemil; Tunc, Senem; Teke, Memik; Hattapoglu, Salih [Dicle University Medical Faculty, Diyarbakir (Turkmenistan)

    2016-04-15

    We aimed to evaluate placental stiffness measured by acoustic radiation force impulse (ARFI) elastography in pregnant women in the second trimester with a normal fetus versus those with structural anomalies and non-structural findings. Forty pregnant women carrying a fetus with structural anomalies diagnosed sonographically at 18-28 weeks of gestation comprised the study group. The control group consisted of 34 healthy pregnant women with a sonographically normal fetus at a similar gestational age. Placental shear wave velocity (SWV) was measured by ARFI elastography and compared between the two groups. Structural anomalies and non-structural findings were scored based on sonographic markers. Placental stiffness measurements were compared among fetus anomaly categories. Doppler parameters of umbilical and uterine arteries were compared with placental SWV measurements. All placental SWV measurements, including minimum SWV, maximum SWV, and mean SWV were significantly higher in the study group than the control group ([0.86 ± 0.2, 0.74 ± 0.1; p < 0.001], [1.89 ± 0.7, 1.59 ± 0.5; p = 0.04], and [1.26 ± 0.4, 1.09 ± 0.2; p = 0.01]), respectively. Placental stiffness evaluated by ARFI elastography during the second trimester in pregnant women with fetuses with congenital structural anomalies is higher than that of pregnant women with normal fetuses.

  16. Regional variation in arterial stiffening and dysfunction in Western diet-induced obesity.

    Science.gov (United States)

    Bender, Shawn B; Castorena-Gonzalez, Jorge A; Garro, Mona; Reyes-Aldasoro, Constantino C; Sowers, James R; DeMarco, Vincent G; Martinez-Lemus, Luis A

    2015-08-15

    Increased central vascular stiffening, assessed in vivo by determination of pulse wave velocity (PWV), is an independent predictor of cardiovascular event risk. Recent evidence demonstrates that accelerated aortic stiffening occurs in obesity; however, little is known regarding stiffening of other disease-relevant arteries or whether regional variation in arterial stiffening occurs in this setting. We addressed this gap in knowledge by assessing femoral PWV in vivo in conjunction with ex vivo analyses of femoral and coronary structure and function in a mouse model of Western diet (WD; high-fat/high-sugar)-induced obesity and insulin resistance. WD feeding resulted in increased femoral PWV in vivo. Ex vivo analysis of femoral arteries revealed a leftward shift in the strain-stress relationship, increased modulus of elasticity, and decreased compliance indicative of increased stiffness following WD feeding. Confocal and multiphoton fluorescence microscopy revealed increased femoral stiffness involving decreased elastin/collagen ratio in conjunction with increased femoral transforming growth factor-β (TGF-β) content in WD-fed mice. Further analysis of the femoral internal elastic lamina (IEL) revealed a significant reduction in the number and size of fenestrae with WD feeding. Coronary artery stiffness and structure was unchanged by WD feeding. Functionally, femoral, but not coronary, arteries exhibited endothelial dysfunction, whereas coronary arteries exhibited increased vasoconstrictor responsiveness not present in femoral arteries. Taken together, our data highlight important regional variations in the development of arterial stiffness and dysfunction associated with WD feeding. Furthermore, our results suggest TGF-β signaling and IEL fenestrae remodeling as potential contributors to femoral artery stiffening in obesity.

  17. Aortic stiffness is associated with white matter integrity in patients with type 1 diabetes

    Energy Technology Data Exchange (ETDEWEB)

    Tjeerdema, Nathanja; Schinkel, Linda D. van [Leiden University Medical Center, Department of Endocrinology and General Internal Medicine (C7-Q), Albinusdreef 2, PO Box 9600, Leiden (Netherlands); Westenberg, Jos J.; Elderen, Saskia G. van; Buchem, Mark A. van; Grond, Jeroen van der; Roos, Albert de [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Smit, Johannes W. [Leiden University Medical Center, Department of Endocrinology and General Internal Medicine (C7-Q), Albinusdreef 2, PO Box 9600, Leiden (Netherlands); University Medical Center Nijmegen, Department of General Internal Medicine, Nijmegen (Netherlands)

    2014-09-15

    To assess the association between aortic pulse wave velocity (PWV) as a marker of arterial stiffness and diffusion tensor imaging of brain white matter integrity in patients with type 1 diabetes using advanced magnetic resonance imaging (MRI) technology. Forty-one patients with type 1 diabetes (23 men, mean age 44 ± 12 years, mean diabetes duration 24 ± 13 years) were included. Aortic PWV was assessed using through-plane velocity-encoded MRI. Brain diffusion tensor imaging (DTI) measurements were performed on 3-T MRI. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were calculated for white and grey matter integrity. Pearson correlation and multivariable linear regression analyses including cardiovascular risk factors as covariates were assessed. Multivariable linear regression analyses revealed that aortic PWV is independently associated with white matter integrity FA (β = -0.777, p = 0.008) in patients with type 1 diabetes. This effect was independent of age, gender, mean arterial pressure, body mass index, smoking, duration of diabetes and glycated haemoglobin levels. Aortic PWV was not significantly related to grey matter integrity. Our data suggest that aortic stiffness is independently associated with reduced white matter integrity in patients with type 1 diabetes. (orig.)

  18. Ambulatory oxygen: why do COPD patients not use their portable systems as prescribed? A qualitative study

    Directory of Open Access Journals (Sweden)

    Fenwick Angela

    2011-02-01

    Full Text Available Abstract Background Patients with COPD on long term oxygen therapy frequently do not adhere to their prescription, and they frequently do not use their ambulatory oxygen systems as intended. Reasons for this lack of adherence are not known. The aim of this study was to obtain in-depth information about perceptions and use of prescribed ambulatory oxygen systems from patients with COPD to inform ambulatory oxygen design, prescription and management. Methods A qualitative design was used, involving semi-structured face-to-face interviews informed by a grounded theory approach. Twenty-seven UK community-dwelling COPD patients using NHS prescribed ambulatory systems were recruited. Ambulatory oxygen systems comprised cylinders weighing 3.4 kg, a shoulder bag and nasal cannulae. Results Participants reported that they: received no instruction on how to use ambulatory oxygen; were uncertain of the benefits; were afraid the system would run out while they were using it (due to lack of confidence in the cylinder gauge; were embarrassed at being seen with the system in public; and were unable to carry the system because of the cylinder weight. The essential role of carers was also highlighted, as participants with no immediate carers did not use ambulatory oxygen outside the house. Conclusions These participants highlighted previously unreported problems that prevented them from using ambulatory oxygen as prescribed. Our novel findings point to: concerns with the lack of specific info